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1

Etemadifar, Masoud, Peyman Roomizadeh, Seyed-Hossein Abtahi, Sepideh Sajjadi, Amin Abedini, Aryan Golabbakhsh, Mahboobeh Fereidan-Esfahani, and Mojtaba Akbari. "Linkage of Multiple Sclerosis and Guillain-Barre Syndrome: A Population-Based Survey in Isfahan, Iran." Autoimmune Diseases 2012 (2012): 1–6. http://dx.doi.org/10.1155/2012/232139.

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Анотація:
Background. Multiple Sclerosis (MS) and Guillain Barre Syndrome (GBS) are autoimmune demyelinating disorders of Central and Peripheral Nervous system, respectively. The coexistence of these two syndromes in an individual's life span is rare.Objectives. To inspect throughout Isfahan MS society (IMSS) records for MS cases who had history of documented GBS whether before the onset of MS or after it.Methods. This retrospective survey was carried out by analyzing the clinical records of 3,522 MS patients who were registered with IMSS, from April 2003 to July 2010. Eligible cases were requested to attend to IMSS for final clinical/paraclinical examinations.Results. Among 3,522 (2,716 women and 806 men) MS subjects, we could identify seven patients (six females and one male) with documented diagnosis of GBS. Six patients (five women and one man) had developed MS within6.5±7.0(range: 1–16) years after being diagnosed with GBS and one (a woman) had developed GBS three years after the diagnosis of MS.Conclusion. It seems that the development of MS in individuals with history of GBS is more than a simple incidental event.
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2

Hassan, Amr, Alaa El-Mazny, Mohammed Saher, Ismail Ibrahim Ismail, and Mohammed Almuqbil. "Co-Occurrence of Guillain-Barre Syndrome and Multiple Sclerosis: A Rare Case Report." Dubai Medical Journal 4, no. 1 (January 25, 2021): 31–35. http://dx.doi.org/10.1159/000512773.

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Анотація:
Guillain-Barre syndrome (GBS) and multiple sclerosis (MS) are autoimmune demyelinating disorders of the peripheral and central nervous systems, respectively. The co-occurrence of these 2 conditions is rare in the literature. Herein, we present a rare case of GBS and MS in a 19-year-old female who presented initially with GBS followed by MS, and we provide a literature review. Despite being rare, it should be kept in mind in the differential diagnosis of patients with atypical and usual presentation of both diseases.
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3

Trojano, M., C. Avolio, M. Ruggieri, F. De Robertis, F. Giuliani, D. Paolicelli, and P. Livrea. "Soluble Intercellular Adhesion Molecule-1 (sICAM-1) in serum and cerebrospinal fluid of demyelinating diseases of the central and peripheral nervous system." Multiple Sclerosis Journal 4, no. 1 (February 1998): 39–44. http://dx.doi.org/10.1177/135245859800400110.

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Анотація:
Serum and cerebrospinal fluid (CSF) soluble Intercellular adhesion molecule-1 (ICAM-1) levels were evaluated (ELISA) in 22 untreated and 13 corticosteroid-treated active relapsing remitting (RR) Multiple Sclerosis (MS), in 10 untreated and 10 corticosteroid-treated Guillain-Barré syndrome (GBS) and in 17 non-inflammatory neurological diseases (NIND). Twenty-eight clinically inactive RR MS were assayed for serum sICAM-1 before and after 3 months treatment of 8 MIU rIFNb-1b taken s.c. every other day. High sICAM-1 serum levels above the NIND values were found in untreated clinically active MS and in untreated GBS (P50.05) but not in the untreated clinically inactive MS group. The active MS group showed significantly (P=0.0001) higher sICAM-1 serum levels if compared to the inactive group. Corticosteroid-treated active MS and GBS patients showed lower (P50.05) serum sICAM-1 levels than the corresponding untreated groups. Serum sICAM-1 levels after 3 months of rIFNb-1b treatment (P50.0001, paired t-test) resulted increased compared to pretreatment values in MS. The mean values of CSF/serum sICAM-1: CSF/serum Albumin ratios (sICAM-1 Index) in active untreated MS patients were higher compared to NIND (P50.005) and to corticosteroid-treated MS group (P=0.01). sICAM Index values in GBS did not differ from those in NIND. The results seem to suggest potential roles for serum sICAM-1 in downregulating the ongoing inflammatory response at the blood-brain barrier level and for CSF sICAM-1 in the maintenance of a central nervous system local immune response.
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4

Rosa-Fraile, Manuel, and Barbara Spellerberg. "Reliable Detection of Group B Streptococcus in the Clinical Laboratory." Journal of Clinical Microbiology 55, no. 9 (June 28, 2017): 2590–98. http://dx.doi.org/10.1128/jcm.00582-17.

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ABSTRACTGroup B streptococcus (GBS) is a leading cause of invasive neonatal infections and a significant pathogen in immunocompromised adults. Screening to detect GBS colonization in pregnant women determines the need for antibiotic prophylaxis in that pregnancy. Efficient determination of the GBS colonization status of pregnant women is crucial. Methods that maximize the probability of GBS recovery are needed. The availability of technologies such as matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS), molecular techniques, and chromogenic culture media, including Granada-type media, have changed the scenario for GBS detection and identification. This review presents and evaluates novel diagnostic tools, as well as classic identification techniques, for GBS species determination.
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5

Tian, David H., Chamini J. Perera, and Gila Moalem-Taylor. "Neuropathic Pain in Animal Models of Nervous System Autoimmune Diseases." Mediators of Inflammation 2013 (2013): 1–13. http://dx.doi.org/10.1155/2013/298326.

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Анотація:
Neuropathic pain is a frequent chronic presentation in autoimmune diseases of the nervous system, such as multiple sclerosis (MS) and Guillain-Barre syndrome (GBS), causing significant individual disablement and suffering. Animal models of experimental autoimmune encephalomyelitis (EAE) and experimental autoimmune neuritis (EAN) mimic many aspects of MS and GBS, respectively, and are well suited to study the pathophysiology of these autoimmune diseases. However, while much attention has been devoted to curative options, research into neuropathic pain mechanisms and relief has been somewhat lacking. Recent studies have demonstrated a variety of sensory abnormalities in different EAE and EAN models, which enable investigations of behavioural changes, underlying mechanisms, and potential pharmacotherapies for neuropathic pain associated with these diseases. This review examines the symptoms, mechanisms, and clinical therapeutic options in these conditions and highlights the value of EAE and EAN animal models for the study of neuropathic pain in MS and GBS.
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6

Sanders, M. E., C. L. Koski, D. Robbins, M. L. Shin, M. M. Frank, and K. A. Joiner. "Activated terminal complement in cerebrospinal fluid in Guillain-Barré syndrome and multiple sclerosis." Journal of Immunology 136, no. 12 (June 15, 1986): 4456–59. http://dx.doi.org/10.4049/jimmunol.136.12.4456.

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Abstract A quantitative enzyme-linked immunosorbent assay was used to measure the concentration of fluid-phase complement C5b-9 complexes (SC5b-9) in the cerebrospinal fluid (CSF) of 14 patients with acute monophasic Guillain-Barré Syndrome (GBS), 21 patients with multiple sclerosis (MS), and 11 patients with noninflammatory central nervous system (CNS) diseases. SC5b-9 complexes were detected in the CSF of 13 of 14 patients with acute GBS (mean, 3.08 micrograms/ml; range, 0 to 7.1 micrograms/ml) and 16 of 21 patients with MS (mean, 1.83 micrograms/ml; range, 0 to 7.5 micrograms/ml). In the control group of patients with noninflammatory CNS diseases, SC5b-9 was not detected in eight of 11 and was present in low concentrations in the remaining three patients (mean, 0.28 micrograms/ml; range, 0 to 1.7 micrograms/ml). The finding of SC5b-9 complexes in the CSF of patients with GBS and MS suggests that terminal complement components may participate in the tissue-damaging processes in these diseases.
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7

Sapugahawatte, Dulmini Nanayakkara, Carmen Li, Priyanga Dharmaratne, Chendi Zhu, Yun Kit Yeoh, Jun Yang, Norman Wai Sing Lo, Kam Tak Wong, and Margaret Ip. "Prevalence and Characteristics of Streptococcus agalactiae from Freshwater Fish and Pork in Hong Kong Wet Markets." Antibiotics 11, no. 3 (March 16, 2022): 397. http://dx.doi.org/10.3390/antibiotics11030397.

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Анотація:
We report the antimicrobial resistance of 191 fish and 61 pork Group B Streptococcus (GBS) procured from Hong Kong wet markets. Two-hundred-and-fifty-two GBS strains were isolated from 992 freshwater fish and 361 pig offal during 2016–2019. The strains were isolated from homogenised samples and plated on selective media, followed by identification through MALDI-TOF-MS. Molecular characterisation, an antibiotic susceptibility test, and biofilm formation were performed on the strains. The isolation rates of the fish GBS and pig GBS were 19.3% (191 strains from 992 freshwater fish) and 16.9% (61 strains from 361 pig organs), respectively. The fish GBS was predominantly serotype Ia, ST7, while pig GBS was serotype III, ST651 (45 strains). An antibiotic susceptibility test revealed that the fish GBS were mostly antibiotic-sensitive, while the pig GBS were multidrug-resistant. A biofilm formation experiment showed that over 71% of fish GBS and all pig GBS had moderate biofilm formation ability. In general, the prevalence rate of GBS in animals and the multidrug resistance phenotype presented in the strains raise concerns about its zoonotic potential and effects on public health.
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8

Ábrók, Marianna, Petra Tigyi, Markus Kostrzewa, Katalin Burián, and Judit Deák. "Evaluation of the Results of Group B Streptococcus Screening by MALDI-TOF MS among Pregnant Women in a Hungarian Hospital." Pathogens 9, no. 1 (December 18, 2019): 1. http://dx.doi.org/10.3390/pathogens9010001.

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Анотація:
Pregnant women colonized by Streptococcus agalactiae, or group B streptococcus (GBS), are at an increased risk of premature delivery and stillbirth, and their neonates can be endangered by the development of an invasive GBS disease. In this study, the results of the GBS screening among pregnant women performed between 2012 and 2018 (n = 19267) are presented. For the GBS positive samples, the antibiotic susceptibility of the isolated strains was also tested (n = 3554). During the examined period, the colonization rate varied between 17.4% and 19.8%. The overall rate of erythromycin and clindamycin resistance in the GBS positive samples was 34.9% and 34.6%, respectively. The frequency of the erythromycin and clindamycin resistant strains showed an increasing tendency. An analysis of the MALDI-TOF MS spectra of 260 GBS isolates revealed that 46.5% of them belonged to either the ST-1 or the ST-17 sequence types, indicating a high prevalence of these potentially invasive GBS strains in our region. More than half of the strains identified as ST-1 (52.1%) proved to be resistant to erythromycin and clindamycin.
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9

An, Hee Dae, Min Su Cho, Hye Jin Mun, Sang Ho Lee, Jin Park, Jaewon Jang, Jin-Hyuk Bae, and In Man Kang. "The Effect of Grain Boundary on Electrical Characteristics in the Source and Drain Regions of Polycrystalline Silicon Based in One Transistor Dynamic Random Access Memory." Journal of Nanoscience and Nanotechnology 21, no. 8 (August 1, 2021): 4258–67. http://dx.doi.org/10.1166/jnn.2021.19396.

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Анотація:
In this paper, we present a capacitorless one transistor dynamic random access memory (1T-DRAM) based on a polycrystalline silicon (poly-Si) double gate MOSFET with grain boundaries (GBs). Several studies have been conducted to implement 1T-DRAM using poly-Si. This is because poly-Si has the advantage of low-cost fabrication and can be stacked. However, poly-Si has GBs, which can adversely affect semiconductor device. So far, related studies on poly-Si-based 1T-DRAM have only focused on GBs present in the channel domain. Hence, in this study, we analyzed the transfer and memory characteristics when a GB is present in the source and drain regions. As a result, we found that in the center of the depletion region in the source and channel junction, where the effect of GB was most significant, sensing margins decreased the most from 0.88 to 0.29 μA/μm, and retention time (RT) decreased from 85 ms to 47 μs. In addition, we found that at the center of the depletion region in the drain and channel junction, where the effect of GBs was most significant in the drain region, RT decreased the most from 85 ms to 52 μs.
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10

Suwantarat, Nuntra, Maureen Grundy, Mayer Rubin, Renee Harris, Jo-Anne Miller, Mark Romagnoli, Ann Hanlon, et al. "Recognition of Streptococcus pseudoporcinus Colonization in Women as a Consequence of Using Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry for Group B Streptococcus Identification." Journal of Clinical Microbiology 53, no. 12 (October 14, 2015): 3926–30. http://dx.doi.org/10.1128/jcm.02363-15.

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Анотація:
During a 14-month period of using matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) for group B streptococcus (GBS) identification, we recovered 32 (1%)Streptococcuspseudoporcinusisolates from 3,276 GBS screening cultures from female genital sources (25 isolates from pregnant women and 7 from nonpregnant women). An additional twoS. pseudoporcinusisolates were identified from a urine culture and a posthysterectomy wound culture. These isolates were found to cross-react with three different GBS antigen agglutination kits, PathoDx (Remel) (93%), Prolex (Pro-Lab Diagnostics) (38%), and Streptex (Remel) (53%). New approaches to bacterial identification in routine clinical microbiology laboratories may affect the prevalence ofS. pseudoporcinus.
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11

Kong, Fanrong, Diana Martin, Gregory James, and Gwendolyn L. Gilbert. "Towards a genotyping system for Streptococcus agalactiae (group B streptococcus): use of mobile genetic elements in Australasian invasive isolates." Journal of Medical Microbiology 52, no. 4 (April 1, 2003): 337–44. http://dx.doi.org/10.1099/jmm.0.05067-0.

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Анотація:
This study forms part of the development of an integrated genotyping system for Streptococcus agalactiae (group B streptococcus, GBS) that can be used to study the population genetics of the organism and the pathogenesis and epidemiology of GBS disease. In recent previous studies, two sets of markers, the capsular polysaccharide synthesis (cps) gene cluster and surface protein antigen genes, have been used to assign molecular serotypes (MS) and protein-gene profiles (PGP) to more than 200 isolates. In the present study, five mobile genetic elements (MGE) have been used as a third set of markers, to characterize further 194 invasive isolates, recovered from blood or cerebrospinal fluid (CSF). Of these, 97 % contained one or more of the five MGE, the distribution of which was related to MS and PGP, as illustrated by MS III, which is divisible into four serosubtypes with different combinations of the MGE (or none). Fifty-six different genotypes and eight genetic clusters were identified, each with different combinations of the three sets of molecular markers. Five predominant genotypes (Ia-1, Ib-1, III-1, III-2 and V-1) contained 62 % of the isolates and five of the eight genetic clusters contained 92 % of the isolates. The 17 CSF isolates were relatively widely distributed between 10 genotypes and across seven of the eight clusters. Further study is needed to determine whether these genotypes or clusters share common markers of increased virulence. In future, comparison of invasive with colonizing strains of GBS may elucidate the significance of these findings.
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12

Toh, Tsun Haw, Nortina Shahrizaila, Mohd Azly Yahya, Khean-Jin Goh, and Cheng Yin Tan. "Can neurophysiology and nerve ultrasound differentiate acute-onset CIDP from GBS with treatment-related fluctuations?" Neurology Asia 27, no. 4 (December 2022): 945–53. http://dx.doi.org/10.54029/2022vku.

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Анотація:
Distinguishing acute-onset chronic inflammatory demyelinating polyneuropathy (A-CIDP) from Guillain- Barré syndrome (GBS) with treatment-related fluctuations (TRF) in the early phase of disease can be challenging. Although characteristic clinical features have been previously reported, there is limited data on neurophysiological features. We aim to identify the electrophysiological and ultrasonographic features that might help differentiate between these two conditions. Patients with GBS-TRF and A-CIDP were identified from an existing cohort of GBS patients presenting to University of Malaya Medical Centre, Kuala Lumpur, Malaysia from 2011 to 2020. The clinical, electrophysiological and nerve ultrasound data were recorded and analysed. Five GBS-TRF (mean age 42 ± 23 years) and five A-CIDP (mean age 66 ± 13 years) patients were included. The mean time to first neurological deterioration was longer in A-CIDP compared to GBS-TRF (11 ± 5 vs 5 ± 1 weeks, p=0.028). Based on two sets of nerve conduction studies (NCS), both GBS-TRF and A-CIDP patients fulfilled the electrodiagnostic criteria for demyelinating neuropathy. A-CIDP patients had more prolonged ulnar minimal F-wave latencies (40.8 ± 5.8 vs 28.6 ± 2.2 ms, p=0.020) and slower sural conduction velocities (26.3 ± 8.6 vs 41.4 ± 3.4 m/s, p=0.015) on NCS. Nerve ultrasound showed significantly larger cross- sectional area of ulnar nerve at the wrist (7 ± 2 vs 5 ± 1 mm2, p=0.037) and forearm (8 ± 1 vs 5 ± 1 mm2, p=0.025) in A-CIDP patients. The Ultrasound Pattern Sum Score-A was significantly higher in A-CIDP compared to GBS-TRF (10 ± 3 vs 5 ± 1, p=0.015). We found nerve electrophysiological and ultrasonographic features can be useful in differentiating between GBS-TRF and A-CIDP.
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13

Maglangit, Fang, Leman, Soldatou, Ebel, Kyeremeh, and Deng. "Accramycin A, a New Aromatic Polyketide, from the Soil Bacterium, Streptomyces sp. MA37." Molecules 24, no. 18 (September 17, 2019): 3384. http://dx.doi.org/10.3390/molecules24183384.

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Анотація:
Drug-like molecules are known to contain many different building blocks with great potential as pharmacophores for drug discovery. The continued search for unique scaffolds in our laboratory led to the isolation of a novel Ghanaian soil bacterium, Streptomyces sp. MA37. This strain produces many bioactive molecules, most of which belong to carbazoles, pyrrolizidines, and fluorinated metabolites. Further probing of the metabolites of MA37 has led to the discovery of a new naphthacene-type aromatic natural product, which we have named accramycin A 1. This molecule was isolated using an HPLC-photodiode array (PDA) guided isolation process and MS/MS molecular networking. The structure of 1 was characterized by detailed analysis of LC-MS, UV, 1D, and 2D NMR data. Preliminary studies on the antibacterial properties of 1 using Group B Streptococcus (GBS) produced a minimum inhibitory concentration (MIC) of 27 µg/mL. This represents the first report of such bioactivity amongst the naphthacene-type aromatic polyketides, and also suggests the possibility for the further development of potent molecules against GBS based on the accramycin scaffold. A putative acc biosynthetic pathway for accramycin, featuring a tridecaketide-specific type II polyketide synthase, was proposed.
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14

Reiber, Hansotto. "Polyspecific antibodies without persisting antigen in multiple sclerosis, neurolupus and Guillain-Barré syndrome: immune network connectivity in chronic diseases." Arquivos de Neuro-Psiquiatria 75, no. 8 (August 2017): 580–88. http://dx.doi.org/10.1590/0004-282x20170081.

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ABSTRACT The polyspecific antibody synthesis in multiple sclerosis (MS) gained diagnostic relevance with the frequent combination of measles-, rubella- and varicella zoster antibodies (MRZ-antibody reaction) but their pathophysiological role remains unknown. This review connects the data for intrathecal polyspecific antibody synthesis in MS and neurolupus with observations in the blood of patients with Guillain-Barré syndrome (GBS). Simultaneously increased antibody and autoantibody titers in GBS blood samples indicate that the polyspecific antibodies are based on a general property of an immune network, supported by the deterministic day-to-day concentration variation of antibodies in normal blood. Strongly correlated measles- and rubella- antibody variations point to a particular connectivity between the MRZ antibodies. The immune network, which provides serological memory in the absence of an antigen, implements the continuous change of the MRZ pattern in blood, not followed by the earlier immigrated B cells without corresponding connectivity in the brain. This may explain the different antibody patterns in cerebrospinal fluid, aqueous humor and blood of the individual MS patient. A complexity approach must implement a different view on causation in chronic diseases and causal therapies.
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15

Bej, Taissa A., Brigid Wilson, Richard Banks, Janet Briggs, Sunah Song, Federico Perez, and Robin Jump. "325. Invasive and Non-Invasive Osteomyelitis Caused by Group B Streptococcus Infection Among Veterans." Open Forum Infectious Diseases 7, Supplement_1 (October 1, 2020): S234—S235. http://dx.doi.org/10.1093/ofid/ofaa439.521.

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Анотація:
Abstract Background Epidemiological studies that assess invasive Group B Streptococcus (GBS) infections may not capture cases of osteomyelitis diagnosed using non-invasive cultures in combination with imaging, laboratory tests, and clinical assessment. Here, we compare GBS osteomyelitis among individuals diagnosed using invasive and non-invasive cultures. Methods Using the Veterans Health Administration corporate data warehouse, we studied a national retrospective cohort review of Veterans diagnosed with GBS osteomyelitis between 2008 – 2017. Invasive cases were defined as an International Classification of Disease (ICD) code for osteomyelitis accompanied by a blood or bone culture positive for GBS within 2 weeks. Non-invasive cases were defined as an ICD code for osteomyelitis and a non-invasive culture positive for GBS from a concordant site within 2 weeks. We compared demographics, comorbid conditions, mortality, and time to below- or above-knee amputation among patients with invasive and non-invasive GBS osteomyelitis. Results We identified 1167 cases of invasive osteomyelitis among 1077 patients and 692 cases of non-invasive osteomyelitis among 644 patients. Most patients were male (98%) with an average age of 63.2 years (± standard deviation (SD) 10.1 years). The Charlson Comorbidity Index (CCI) was similar among patients with invasive and non-invasive disease (3.85 ± SD 2.3 and 3.83 ± SD2.4, respectively). Among those with lower extremity osteomyelitis, 11% of invasive cases had an amputation at 30 days while 2% of non-invasive cases had an amputation in the same time frame (Figure 1). Mortality was similar among those with invasive and non-invasive GBS osteomyelitis at 30-days (1% and 1%, respectively) and at 1-year (11% and 9%, respectively) (Figure 2). Figure 1: Time to Amputation Figure 2: Survival Conclusion Over 1/3 of the cases of osteomyelitis caused by GBS do not meet the case definition for invasive disease. Whether diagnosed using invasive or non-invasive microbiological cultures, survival outcomes for people with GBS osteomyelitis were similar. These findings suggest that non-invasive GBS osteomyelitis is as clinically important as invasive GBS osteomyelitis and that the rates of GBS osteomyelitis may be higher than previously reported. Disclosures Federico Perez, MD, MS, Accelerate (Research Grant or Support)Merck (Research Grant or Support)Pfizer (Research Grant or Support) Robin Jump, MD, PhD, Accelerate (Grant/Research Support)Merck (Grant/Research Support)Pfizer (Grant/Research Support, Advisor or Review Panel member)Roche (Advisor or Review Panel member)
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16

Chung, Chia-Ru, Hsin-Yao Wang, Po-Han Chou, Li-Ching Wu, Jang-Jih Lu, Jorng-Tzong Horng, and Tzong-Yi Lee. "Towards Accurate Identification of Antibiotic-Resistant Pathogens through the Ensemble of Multiple Preprocessing Methods Based on MALDI-TOF Spectra." International Journal of Molecular Sciences 24, no. 2 (January 5, 2023): 998. http://dx.doi.org/10.3390/ijms24020998.

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Анотація:
Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) has been used to identify microorganisms and predict antibiotic resistance. The preprocessing method for the MS spectrum is key to extracting critical information from complicated MS spectral data. Different preprocessing methods yield different data, and the optimal approach is unclear. In this study, we adopted an ensemble of multiple preprocessing methods––FlexAnalysis, MALDIquant, and continuous wavelet transform-based methods––to detect peaks and build machine learning classifiers, including logistic regressions, naïve Bayes classifiers, random forests, and a support vector machine. The aim was to identify antibiotic resistance in Acinetobacter baumannii, Acinetobacter nosocomialis, Enterococcus faecium, and Group B Streptococci (GBS) based on MALDI-TOF MS spectra collected from two branches of a referral tertiary medical center. The ensemble method was compared with the individual methods. Random forest models built with the data preprocessed by the ensemble method outperformed individual preprocessing methods and achieved the highest accuracy, with values of 84.37% (A. baumannii), 90.96% (A. nosocomialis), 78.54% (E. faecium), and 70.12% (GBS) on independent testing datasets. Through feature selection, important peaks related to antibiotic resistance could be detected from integrated information. The prediction model can provide an opinion for clinicians. The discriminative peaks enabling better prediction performance can provide a reference for further investigation of the resistance mechanism.
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17

Marchiorji, Paulo E., Marisa dos Reis, Maria E. Z. Quevedo, D. Callegaro, M. Teresa A. Hirata, M. Scaff, and R. Manoel de Oliveira. "Cerebrospinal fluid and serum antiphospholipid antibodies in multiple sclerosis, Guillain-Barré syndrome and systemic lupus arythematosus." Arquivos de Neuro-Psiquiatria 48, no. 4 (December 1990): 465–68. http://dx.doi.org/10.1590/s0004-282x1990000400010.

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Анотація:
Immuneglobulins isotypes (IgG and IgM) for myelin basic protein (MBP), cerebrosides (CER), gangliosides (GANG) and cardiolipin (CARD) were detected in the cerebrospinal fluid (CSF) from 33 patients with multiple sclerosis (MS), 18 with Guillain-Barré syndrome (GBS) and 30 with systemic lupus erythematosus (SLE). In MS patients occurred positive and significant levels of IgG-MBP in 51,5% (p<0.05) and IgM-MBP in only 18.2%, IgG-CARD in 46.2%, as long as CER and GANG were detected in almost 20%. From serum samples of MS patients 20.6% presented IgG-MBP, while 53% showed positive levels foi IgM-MBP. The CSF analysis of patients with GBS showed that 56.3% revealed IgG-MBP (p<0.05), 53% for IgM-MBP. 3&.5% for IgG-CER and 23% for IgM-CER, while 50% of patients had IgG-CARD, as long -as 31% also had IgG-GANG. The serum evaluation from 14 patients showed that 18.8% had positive concentrations of IgG-MBP and 56.3% presented IgM-MBP (p<0.05) Except for 50% of patients with SLE who presented positive CSF levels of IgG-CARD. only 24.1% had positive levels of IgG-MBP. We believe that the presence of antiphosphohoid antibodies in CSF of the above mentioned diseases occurred as immune epiphenomena, but their appearance would permit the maintenance of and perpetuate the immune event.
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18

Groff, Stephanie McKenney, Wareef Fallatah, Samuel Yang, Jamie Murphy, Christopher Crutchfield, Mark Marzinke, Joanne Kurtzberg, Carlton K. K. Lee, Irina Burd, and Azadeh Farzin. "Effect of Maternal Obesity on Maternal-Fetal Transfer of Preoperative Cefazolin at Cesarean Section." Journal of Pediatric Pharmacology and Therapeutics 22, no. 3 (May 1, 2017): 227–32. http://dx.doi.org/10.5863/1551-6776-22.3.227.

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OBJECTIVES American Congress of Obstetricians and Gynecologists recommends a single dose of antibiotic prophylaxis before all cesarean sections (C/S). This recommendation is based on pharmacokinetic studies that include only non-obese patients. We sought to evaluate 1) cefazolin plasma concentrations among obese and non-obese patients after administration of a 2-g cefazolin dose for prevention of surgical wound infections, and 2) whether cefazolin concentration in fetal circulation may be protective against pathogens that cause early onset neonatal sepsis. METHODS Maternal and fetal cefazolin plasma concentrations were compared between obese (body mass index [BMI] ≥ 30 kg/m2) and non-obese (BMI &lt; 25 kg/m2) healthy, term pregnant women undergoing scheduled C/S. Liquid chromatographic–tandem mass spectrometric (LC-MS/MS) methods were used for quantification of total and free cefazolin concentrations in maternal blood (MB) and umbilical cord blood (UCB). RESULTS Eight women were screened and consented. There was no difference between groups in MB total and free cefazolin concentrations. All MB samples had total and free cefazolin concentrations greater than the minimum inhibitory concentration 90 (MIC90) for Group B Streptococcus (GBS), Staphylococcus aureus, and Escherichia coli. All UCB samples had total and free cefazolin concentrations greater than MIC90 for GBS and S aureus, even when administered as briefly as 18 minutes before delivery. A lower concentration of total cefazolin was detected in UCB of neonates of obese women compared to non-obese women (p &gt; 0.05). CONCLUSIONS Administration of 2 g of cefazolin to women undergoing scheduled C/S might be an adequate prophylactic dose for surgical wound infection in both non-obese and obese patients; and cefazolin concentration in fetal circulation may be protective against GBS and S aureus.
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19

Davies, Alexander J., Janev Fehmi, Makbule Senel, Hayrettin Tumani, Johannes Dorst, and Simon Rinaldi. "Immunoadsorption and Plasma Exchange in Seropositive and Seronegative Immune-Mediated Neuropathies." Journal of Clinical Medicine 9, no. 7 (June 27, 2020): 2025. http://dx.doi.org/10.3390/jcm9072025.

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The inflammatory neuropathies are disabling conditions with diverse immunological mechanisms. In some, a pathogenic role for immunoglobulin G (IgG)-class autoantibodies is increasingly appreciated, and immunoadsorption (IA) may therefore be a useful therapeutic option. We reviewed the use of and response to IA or plasma exchange (PLEx) in a cohort of 41 patients with nodal/paranodal antibodies identified from a total of 573 individuals with suspected inflammatory neuropathies during the course of routine diagnostic testing (PNAb cohort). 20 patients had been treated with PLEx and 4 with IA. Following a global but subjective evaluation by their treating clinicians, none of these patients were judged to have had a good response to either of these treatment modalities. Sequential serology of one PNAb+ case suggests prolonged suppression of antibody levels with frequent apheresis cycles or adjuvant therapies, may be required for effective treatment. We further retrospectively evaluated the serological status of 40 patients with either Guillain-Barré syndrome (GBS) or chronic inflammatory demyelinating polyneuropathy (CIDP), and a control group of 20 patients with clinically-isolated syndrome/multiple sclerosis (CIS/MS), who had all been treated with IgG-depleting IA (IA cohort). 32 of these patients (8/20 with CIDP, 13/20 with GBS, 11/20 with MS) were judged responsive to apheresis despite none of the serum samples from this cohort testing positive for IgG antibodies against glycolipids or nodal/paranodal cell-adhesion molecules. Although negative on antigen specific assays, three patients’ pre-treatment sera and eluates were reactive against different components of myelinating co-cultures. In summary, preliminary evidence suggests that GBS/CIDP patients without detectable IgG antibodies on routine diagnostic tests may nevertheless benefit from IA, and that an unbiased screening approach using myelinating co-cultures may assist in the detection of further autoantibodies which remain to be identified in such patients.
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20

Joyce, Luke R., Haider S. Manzer, Jéssica da C. Mendonça, Ricardo Villarreal, Prescilla E. Nagao, Kelly S. Doran, Kelli L. Palmer, and Ziqiang Guan. "Identification of a novel cationic glycolipid in Streptococcus agalactiae that contributes to brain entry and meningitis." PLOS Biology 20, no. 2 (February 18, 2022): e3001555. http://dx.doi.org/10.1371/journal.pbio.3001555.

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Bacterial membrane lipids are critical for membrane bilayer formation, cell division, protein localization, stress responses, and pathogenesis. Despite their critical roles, membrane lipids have not been fully elucidated for many pathogens. Here, we report the discovery of a novel cationic glycolipid, lysyl-glucosyl-diacylglycerol (Lys-Glc-DAG), which is synthesized in high abundance by the bacterium Streptococcus agalactiae (Group B Streptococcus, GBS). To our knowledge, Lys-Glc-DAG is more positively charged than any other known lipids. Lys-Glc-DAG carries 2 positive net charges per molecule, distinct from the widely described lysylated phospholipid lysyl-phosphatidylglycerol (Lys-PG) that carries one positive net charge due to the presence of a negatively charged phosphate moiety. We use normal phase liquid chromatography (NPLC) coupled with electrospray ionization (ESI) high-resolution tandem mass spectrometry (HRMS/MS) and genetic approaches to determine that Lys-Glc-DAG is synthesized by the enzyme MprF in GBS, which covalently modifies the neutral glycolipid Glc-DAG with the cationic amino acid lysine. GBS is a leading cause of neonatal meningitis, which requires traversal of the endothelial blood–brain barrier (BBB). We demonstrate that GBS strains lacking mprF exhibit a significant decrease in the ability to invade BBB endothelial cells. Further, mice challenged with a GBSΔmprF mutant developed bacteremia comparably to wild-type (WT) infected mice yet had less recovered bacteria from brain tissue and a lower incidence of meningitis. Thus, our data suggest that Lys-Glc-DAG may contribute to bacterial uptake into host cells and disease progression. Importantly, our discovery provides a platform for further study of cationic lipids at the host–pathogen interface.
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21

Uasuf, Carina Gabriela, Elisabetta De Angelis, Rocco Guagnano, Rosa Pilolli, Claudia D’Anna, Danilo Villalta, Ignazio Brusca, and Linda Monaci. "Emerging Allergens in Goji Berry Superfruit: The Identification of New IgE Binding Proteins towards Allergic Patients’ Sera." Biomolecules 10, no. 5 (April 29, 2020): 689. http://dx.doi.org/10.3390/biom10050689.

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The goji berry (Lycium barbarum L.) (GB) is gaining increasing attention with high consumption worldwide due to its exceptional nutritional value and medicinal benefits displayed in humans. Beyond their beneficial properties, GBs contain renowned allergenic proteins, and therefore deserve inclusion among the allergenic foods capable of inducing allergic reactions in sensitive consumers. GB allergy has been frequently linked to the panallergen lipid transfer protein (LTP), especially across the population of the Mediterranean area. Methods: In this study, we investigated the protein profile of GBs focusing on the most reactive proteins against immunoglobulins E (IgE) of allergic patients’ sera, as ascertained by immunoblot experiments. The protein spots displaying a clear reaction were excised, in-gel digested, and analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) followed by data searching against a restricted database for a reliable protein identification. Results: According to our data, three main spots were identified in GB extract as IgE binding proteins after immunoblot analysis. Some major proteins were identified and the three proteins that provided the highest reactivity were putatively attributed to vicilin and legumin proteins followed by a protein matching with 11S globulin belonging to the cupin superfamily. Finally, the whole GB protein extract was also submitted to bottom-up proteomics followed by a software-based database (DB) screening and a more exhaustive list of GB proteins was compiled.
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22

Langer-Gould, A., KB Albers, SK Van Den Eeden, and LM Nelson. "Autoimmune diseases prior to the diagnosis of multiple sclerosis: a population-based case-control study." Multiple Sclerosis Journal 16, no. 7 (May 12, 2010): 855–61. http://dx.doi.org/10.1177/1352458510369146.

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The objective of this study was to determine whether patients with multiple sclerosis (MS) are more likely to have other autoimmune disorders particularly prior to the diagnosis of MS. We conducted a population-based case—control study of patients enrolled in the Northern California Kaiser Permanente Medical Care Program. Electronic clinical records through 2005 were used to ascertain incident and prevalent MS cases and identify the presence and timing of 44 other diagnoses. Controls were matched 5:1 for gender, age, and Kaiser membership characteristics. We identified 5296 MS cases (including 924 diagnosed between 2001 and 2004) and 26,478 matched controls. Prior to MS diagnosis, cases were more likely than controls to have uveitis (OR = 3.2, 95%; CI 1.7—5.7), inflammatory bowel disease (IBD, OR = 1.7; 95%CI 1.2—2.5), and Bell’s palsy (OR = 3.2; 95%CI 1.2—8.3). Cases were also more likely to develop Guillain— Barré syndrome (GBS, OR = 5.0; 95%CI 1.6—15.4) and bullous pemphigoid (OR = 6.7; 95%CI 1.5—29.9). Cases were not more likely than controls to have or to develop rheumatoid arthritis, lupus or thyroiditis. MS may share environmental triggers, genetic susceptibilities and/or alterations in immune homeostasis with IBD and uveitis, but not with other autoimmune disorders.
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23

Sinanović, Osman, Sanela Zukić, Adnan Burina, Nermina Pirić, Renata Hodžić, Mirza Atić, Mirna Alečković-Halilović, and Enisa Mešić. "Plasmapheresis in neurological disorders: six years experience from University Clinical center Tuzla." F1000Research 6 (July 26, 2017): 1234. http://dx.doi.org/10.12688/f1000research.11841.1.

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Background: Therapeutic plasma exchange (TPE) is an extracorporeal blood purification technique that is designed to remove substances with a large molecular weight. The TPE procedure includes removal of antibodies, alloantibodies, immune complexes, monoclonal protein, toxins or cytokines, and involves the replenishment of a specific plasma factor. The aim of the study was to describe the clinical response to TPE in various neurological patients, and to assess the clinical response to this therapy. Methods: The study was retrospective. We analyzed the medical records of 77 patients who were treated at the Department of Neurology, University Clinical Center (UCC) Tuzla from 2011 to 2016. Results: 83 therapeutic plasma exchanges were performed in the 77 patients. There was a slight predominance of male patients (54.5%), with an average age of 51±15.9 years. The most common underlying neurological diseases were Guillain–Barré syndrome (GBS) (37.7%), then chronic inflammatory demyelinating polyneuropathy (CIDP) (23.4%), multiple sclerosis (MS) (11.7%) and myasthenia gravis (10.4%). Less frequent neurological diseases that were encountered were paraneoplastic polyneuropathies (5.2%), neuromyelitis optica (also known as Devic’s disease) (3.9%), motor neuron disease (3.9%), polymyositis (2.6%) and multifocal motor neuropathy (1.2%). Conclusions: Six years experience of therapeutic plasma exchange in neurological patients in our department have shown that, following evidence-based guidelines for plasmapheresis, the procedure was most effective in patients with GBS, CIDP and myasthenia gravis.
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24

Koike, Haruki, and Masahisa Katsuno. "Macrophages and Autoantibodies in Demyelinating Diseases." Cells 10, no. 4 (April 8, 2021): 844. http://dx.doi.org/10.3390/cells10040844.

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Myelin phagocytosis by macrophages has been an essential feature of demyelinating diseases in the central and peripheral nervous systems, including Guillain–Barré syndrome (GBS), chronic inflammatory demyelinating polyneuropathy (CIDP), and multiple sclerosis (MS). The discovery of autoantibodies, including anti-ganglioside GM1 antibodies in the axonal form of GBS, anti-neurofascin 155 and anti-contactin 1 antibodies in typical and distal forms of CIDP, and anti-aquaporin 4 antibodies in neuromyelitis optica, contributed to the understanding of the disease process in a subpopulation of patients conventionally diagnosed with demyelinating diseases. However, patients with these antibodies are now considered to have independent disease entities, including acute motor axonal neuropathy, nodopathy or paranodopathy, and neuromyelitis optica spectrum disorder, because primary lesions in these diseases are distinct from those in conventional demyelinating diseases. Therefore, the mechanisms underlying demyelination caused by macrophages remain unclear. Electron microscopy studies revealed that macrophages destroy myelin as if they are the principal players in the demyelination process. Recent studies suggest that macrophages seem to select specific sites of myelinated fibers, including the nodes of Ranvier, paranodes, and internodes, for the initiation of demyelination in individual cases, indicating that specific components localized to these sites play an important role in the behavior of macrophages that initiate myelin phagocytosis. Along with the search for autoantibodies, the ultrastructural characterization of myelin phagocytosis by macrophages is a crucial step in understanding the pathophysiology of demyelinating diseases and for the future development of targeted therapies.
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25

Thapa, Kapil, and Puja Jaiswal. "Assessment of Oral Cancer: A Study in Nepal Cancer Hospital and Research Center, Harisiddhi, Lalitpur, Nepal." Journal of Institute of Science and Technology 27, no. 2 (November 7, 2022): 31–37. http://dx.doi.org/10.3126/jist.v27i2.39139.

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Oral cancer is becoming very common and increasing day by day in Nepal. It ranks 6th in the world and 5th in Nepal among all types of cancer as of 2018. This is a hospital-based retrospective study. Required details of 128 patients who underwent surgery from 1st April 2018 to 30th October 2019 in Nepal Cancer Hospital and Research Center, Lalitpur. Data were collected age-wise, sex-wise, site-wise, and stage-wise prevalence was figured out. The data were analyzed using MS excel 2007. It was found that males were more commonly affected than females with the mean age for males at diagnosis being 53.3 years and females being 55.62 years. The tongue was the most affected site followed by GBS then buccal mucosa and RMT. Most people knew about cancer growing on them only at advanced stages.
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26

Sriwastava, Shitiz, Kanika Sharma, Syed Hassan Khalid, Sakhi Bhansali, Ashish K. Shrestha, Mahmoud Elkhooly, Samiksha Srivastava, Erum Khan, Shruti Jaiswal, and Sijin Wen. "COVID-19 Vaccination and Neurological Manifestations: A Review of Case Reports and Case Series." Brain Sciences 12, no. 3 (March 18, 2022): 407. http://dx.doi.org/10.3390/brainsci12030407.

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Background: With 10 vaccines approved by the WHO and nearly 48% of people fully vaccinated worldwide, we have observed several individual case studies of neurological manifestations post-COVID-19 vaccination. Through this systematic review, we aim to discern these CNS and PNS manifestations following the COVID-19 vaccine to help produce methods to mitigate them. Methods: We conducted a thorough literature search of Google Scholar and PubMed from 1 December 2020 until 10 October 2021 and included all the case studies of COVID-19 vaccine-associated neurological side effects. The literature search and data analysis were performed by two independent reviewers according to prespecified inclusion and exclusion criteria using PRISMA. Results: The most common CNS manifestation was CVST (14.47%), found in females (64%) younger than 50 years (71%) after the first AstraZeneca dose (93%). Others included CNS demyelinating disorders (TM, ADEM, MS, NMOSD) (9.30%), encephalopathy/encephalitis (3.10%), and others (4.13%). The most common PNS manifestation was GBS (14.67%) found in males (71%) older than 50 years (79%), followed by Bell’s palsy (5.24%) and others (2.10%). Most occurred with the AstraZeneca (28.55%), Pfizer-BioNTech (9.18%), and Moderna (8.16%) vaccines. Nine (64%) out of the 14 patients with CVST died. However, most cases overall (42 out of 51) were non-fatal (82%). Conclusion: Several CNS and PNS adverse events have occurred post-COVID-19 vaccination, including CVST, GBS, and TM. High vigilance with early identification and treatment leads to better outcomes. Further studies with non-vaccinated controls might help in understanding the pathophysiologic mechanisms of these neurological manifestations following COVID-19 vaccination.
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Fan, Xueli, Hongliang Zhang, Yun Cheng, Xinmei Jiang, Jie Zhu, and Tao Jin. "Double Roles of Macrophages in Human Neuroimmune Diseases and Their Animal Models." Mediators of Inflammation 2016 (2016): 1–13. http://dx.doi.org/10.1155/2016/8489251.

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Macrophages are important immune cells of the innate immune system that are involved in organ-specific homeostasis and contribute to both pathology and resolution of diseases including infections, cancer, obesity, atherosclerosis, and autoimmune disorders. Multiple lines of evidence point to macrophages as a remarkably heterogeneous cell type. Different phenotypes of macrophages exert either proinflammatory or anti-inflammatory roles depending on the cytokines and other mediators that they are exposed to in the local microenvironment. Proinflammatory macrophages secrete detrimental molecules to induce disease development, while anti-inflammatory macrophages produce beneficial mediators to promote disease recovery. The conversion of the phenotypes of macrophages can regulate the initiation, development, and recovery of autoimmune diseases. Human neuroimmune diseases majorly include multiple sclerosis (MS), neuromyelitis optica (NMO), myasthenia gravis (MG), and Guillain-Barré syndrome (GBS) and macrophages contribute to the pathogenesis of these neuroimmune diseases. In this review, we summarize the double roles of macrophage in neuroimmune diseases and their animal models to further explore the mechanisms of macrophages involved in the pathogenesis of these disorders, which may provide a potential therapeutic approach for these disorders in the future.
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28

Tong, Lu, Shanhan Cheng, Honghao Lv, Chengzhi Zhao, Jie Zhu, Pingwu Liu, Zhiwei Wang, Limei Yang, and Yangyong Zhang. "Analysis of Glucosinolate Content, Composition and Expression Level of Biosynthesis Pathway Genes in Different Chinese Kale Varieties." Horticulturae 7, no. 10 (October 14, 2021): 398. http://dx.doi.org/10.3390/horticulturae7100398.

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The content and component of glucosinolates in edible stems and leaves of eight Chinese kale varieties from Japan and eight varieties from China were determined by HPLC-MS. Simultaneously, the expression levels of glucosinolate biosynthesis pathway genes from four varieties with high and low total glucosinolate contents were analyzed by the qRT-PCR method. Four types of aliphatic glucosinolates (A-GLSs: GRA, SIN, GNA and GER) and indole glucosinolates (I-GLSs: 4-HGBS, GBS, 4-MGBS and NGBS) were detected in the stems and leaves of 16 varieties, and no aromatic glucosinolates (R-GLSs) were detected. A-GLSs account for more than 80.69% of the total content of total glucosinolates (T-GLSs), in which GNA and GRA are the main components of stems and leaves. Among Japanese varieties, QB1 has higher content of A- and T-GLSs, while that of XLB was lower; however, the corresponding varieties were ZH and DSHH in Chinese varieties. Among the above four varieties, the expression levels of SOT16, CYP83B1, SOT17, CYP83A1 and MAM1 genes were significantly higher in the varieties with higher GLSs; the expression levels of SOT16 and CYP83B1 were consistent with the content of I-GLSs; and SOT17, CYP83A1 and MAM1 expression levels were consistent with A-GLSs content. At the same time, the expression levels of SOT16 and CYP83B1 in the leaves were higher than those in the stems. CYP83A1 and MAM1 genes were less expressed in the leaves than in the stems of lower content varieties. It is speculated that these genes may be the key genes regulating GLS biosynthesis in Chinese kale.
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Tong, Lu, Shanhan Cheng, Honghao Lv, Chengzhi Zhao, Jie Zhu, Pingwu Liu, Zhiwei Wang, Limei Yang, and Yangyong Zhang. "Analysis of Glucosinolate Content, Composition and Expression Level of Biosynthesis Pathway Genes in Different Chinese Kale Varieties." Horticulturae 7, no. 10 (October 14, 2021): 398. http://dx.doi.org/10.3390/horticulturae7100398.

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Анотація:
The content and component of glucosinolates in edible stems and leaves of eight Chinese kale varieties from Japan and eight varieties from China were determined by HPLC-MS. Simultaneously, the expression levels of glucosinolate biosynthesis pathway genes from four varieties with high and low total glucosinolate contents were analyzed by the qRT-PCR method. Four types of aliphatic glucosinolates (A-GLSs: GRA, SIN, GNA and GER) and indole glucosinolates (I-GLSs: 4-HGBS, GBS, 4-MGBS and NGBS) were detected in the stems and leaves of 16 varieties, and no aromatic glucosinolates (R-GLSs) were detected. A-GLSs account for more than 80.69% of the total content of total glucosinolates (T-GLSs), in which GNA and GRA are the main components of stems and leaves. Among Japanese varieties, QB1 has higher content of A- and T-GLSs, while that of XLB was lower; however, the corresponding varieties were ZH and DSHH in Chinese varieties. Among the above four varieties, the expression levels of SOT16, CYP83B1, SOT17, CYP83A1 and MAM1 genes were significantly higher in the varieties with higher GLSs; the expression levels of SOT16 and CYP83B1 were consistent with the content of I-GLSs; and SOT17, CYP83A1 and MAM1 expression levels were consistent with A-GLSs content. At the same time, the expression levels of SOT16 and CYP83B1 in the leaves were higher than those in the stems. CYP83A1 and MAM1 genes were less expressed in the leaves than in the stems of lower content varieties. It is speculated that these genes may be the key genes regulating GLS biosynthesis in Chinese kale.
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30

Dorst, Johannes, Frank Fillies, Jens Dreyhaupt, Makbule Senel, and Hayrettin Tumani. "Safety and Tolerability of Plasma Exchange and Immunoadsorption in Neuroinflammatory Diseases." Journal of Clinical Medicine 9, no. 9 (September 5, 2020): 2874. http://dx.doi.org/10.3390/jcm9092874.

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Plasma exchange (PE) and immunoadsorption (IA) are frequently used for treatment of various autoimmune-mediated neurological diseases, including multiple sclerosis (MS), chronic inflammatory demyelinating polyneuropathy (CIDP), and Guillain–Barré syndrome (GBS). Although both methods are generally regarded as well-tolerated treatment options, evidence for safety and tolerability is low for most indications and largely relies on small case series. In this study, we retrospectively analysed adverse events (AEs) and laboratory changes in 284 patients with various neurological indications who received either PE (n = 65, 113 cycles) or IA (n = 219, 435 cycles) between 2013 and 2020 in our Neurology department. One standard treatment cycle for PE as well as IA consisted of five treatments on five consecutive days. During every treatment, the 2.0–2.5-fold individual plasma volume (PV) was treated in IA, while in PE, the 0.7-fold individual PV was replaced by human albumin solution. Overall, both methods showed an excellent safety profile; no deaths of life-threatening adverse events were recorded. Severe AEs (corresponding to grade 3 on the Common Terminology Criteria for Adverse Events grading scale v5.0) including three patients with sepsis, one pneumonia, and one pneumothorax were present in 5/435 IA cycles (1.1%); in the PE group, no severe AEs were recorded. Furthermore, although advantageous tolerability is generally considered the main advantage of IA over PE, we found that overall frequency of AEs (including grades 1 and 2) was higher in IA (67.1% of all cycles) compared to PE (35.4%; p < 0.001). The low incidence of AEs in PE might be caused by the lower PV exchanged during each treatment (0.7-fold) compared to previous studies which predominantly exchanged the 1.0–1.5-fold PV. In order to verify this hypothesis as well as confirming the efficacy of this lower-dosed scheme, prospective studies comparing different treatment regimens are needed.
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31

Fawad, Nadir, Taixun Liu, Daidu Fan, and Qazi Adnan Ahmad. "Sedimentary Facies Analysis of the Third Eocene Member of Shahejie Formation in the Bonan Sag of Bohai Bay Basin (China): Implications for Facies Heterogeneities in Sandstone Reservoirs." Energies 15, no. 17 (August 25, 2022): 6168. http://dx.doi.org/10.3390/en15176168.

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The middle sub-member (Es3z) within the third member (Es3) of the Eocene Shahejie formation is the main source of the generation and accumulation of hydrocarbons in the lacustrine deltas of Bonan depression. Exploration and research work in different blocks is carried out separately. Types of sedimentary facies, and their vertical and lateral evolution in Es3z are not studied in detail. To fill this knowledge gap, we did a detailed analysis of facies and lithological characteristics through integrative studies of cores, well logs and seismic data. Identification of sedimentary structures and lithology of the reservoir zone from cores are calibrated with high-quality well logs and seismic data. Depositional facies in Es3z reservoirs are identified through analysis of sedimentary structures, grain size, log’s trends and seismic sections. Es3z was deposited in the fan delta front setting where five facies associations are found, among them distributary channels consisting of MCS, CSg, PCSs, MS, RCL, WCS, PBSs, RCS and GBS lithofacies, natural levee containing DFs, and furthermore, sheet sand are associated to CBS and SSM lithofacies. GM, GGM and DGM lithofacies are related to inter-distributary deposits, whereas mouth bars consist of PLS, CS and CFS. Depositional history, flow direction of the sediments, and facies distribution are investigated through detailed facies mapping and cross-section profiling to show that the sediments were sourced from southeast to northwest. We found thicker succession of sedimentary profiles towards north and north-west directions. Belt distributary channel deposits, covering a wide range of areas, act as potential reservoirs along with mouth bar deposits, while mudstones in interdistributary channels act as a good source and seal rocks. The methodology adopted has great potential to explore the reservoirs of fan delta front in lacustrine deltas.
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32

Bąk, Beata, Marek Sikorski, and Aleksandra Woźniak. "Demographic conditioning of awareness of prophylaxis against Streptococcus agalactiae (GBS) infections among parturients." Medical Studies 3 (2016): 170–78. http://dx.doi.org/10.5114/ms.2016.62307.

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33

Wang, Hsin-Yao, Wen-Chi Li, Kai-Yao Huang, Chia-Ru Chung, Jorng-Tzong Horng, Jen-Fu Hsu, Jang-Jih Lu, and Tzong-Yi Lee. "Rapid classification of group B Streptococcus serotypes based on matrix-assisted laser desorption ionization-time of flight mass spectrometry and machine learning techniques." BMC Bioinformatics 20, S19 (December 2019). http://dx.doi.org/10.1186/s12859-019-3282-7.

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Abstract Background Group B streptococcus (GBS) is an important pathogen that is responsible for invasive infections, including sepsis and meningitis. GBS serotyping is an essential means for the investigation of possible infection outbreaks and can identify possible sources of infection. Although it is possible to determine GBS serotypes by either immuno-serotyping or geno-serotyping, both traditional methods are time-consuming and labor-intensive. In recent years, the matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has been reported as an effective tool for the determination of GBS serotypes in a more rapid and accurate manner. Thus, this work aims to investigate GBS serotypes by incorporating machine learning techniques with MALDI-TOF MS to carry out the identification. Results In this study, a total of 787 GBS isolates, obtained from three research and teaching hospitals, were analyzed by MALDI-TOF MS, and the serotype of the GBS was determined by a geno-serotyping experiment. The peaks of mass-to-charge ratios were regarded as the attributes to characterize the various serotypes of GBS. Machine learning algorithms, such as support vector machine (SVM) and random forest (RF), were then used to construct predictive models for the five different serotypes (Types Ia, Ib, III, V, and VI). After optimization of feature selection and model generation based on training datasets, the accuracies of the selected models attained 54.9–87.1% for various serotypes based on independent testing data. Specifically, for the major serotypes, namely type III and type VI, the accuracies were 73.9 and 70.4%, respectively. Conclusion The proposed models have been adopted to implement a web-based tool (GBSTyper), which is now freely accessible at http://csb.cse.yzu.edu.tw/GBSTyper/, for providing efficient and effective detection of GBS serotypes based on a MALDI-TOF MS spectrum. Overall, this work has demonstrated that the combination of MALDI-TOF MS and machine intelligence could provide a practical means of clinical pathogen testing.
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34

Ghahremani, AmirAli, Amir Bigdeli, Davoud Salarbashi, Pouyan Shakouri, and Sepideh Elyasi. "A Case Report of Three Guillain-Barré Syndrome During SARS-CoV-2 Pandemic: Promising Outcome in a Patient with History of Multiple Sclerosis." Journal of Pharmaceutical Care, October 3, 2022. http://dx.doi.org/10.18502/jpc.v10i3.10800.

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Анотація:
Neurologic complications in patients with coronavirus disease 19 (COVID-19) are common particularly in hospitalized patients. Guillain–Barré syndrome (GBS) is a rare complication of COVID-19. Most patients with GBS and COVID-19 presented with progressive, ascending limb weakness evolving over one to four days. There are some reported cases of GBS, mostly in form of case reports or case series, and also a comprehensive review on this topic. However, none of these cases experienced multiple sclerosis (MS) as an underlying disease. So, in this manuscript we reported three cases of COVID-19 induced GBS; one of them with history of MS and promising outcome after receiving five sessions of plasmapheresis and corticosteroid therapy.
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Yu, Donghong, Bin Liang, Haipo Xu, Lu Chen, Zhoujie Ye, Zhihui Wu, and Xinrui Wang. "CRISPR/Cas12a-based assay for the rapid and high-sensitivity detection of Streptococcus agalactiae colonization in pregnant women with premature rupture of membrane." Annals of Clinical Microbiology and Antimicrobials 22, no. 1 (January 19, 2023). http://dx.doi.org/10.1186/s12941-023-00558-2.

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Abstract Background Streptococcus agalactiae or group B Streptococcus (GBS) is a leading infectious cause of neonatal morbidity and mortality. It is essential to establish a robust method for the rapid and ultra-sensitive detection of GBS in pregnant women with premature rupture of membrane (PROM). Methods This study developed a CRISPR-GBS assay that combined the advantages of the recombinase polymerase amplification (RPA) and CRISPR/Cas12a system for GBS detection. The clinical performance of the CRISPR-GBS assay was assessed using vaginal or cervical swabs that were collected from 179 pregnant women with PROM, compared in parallel to culture-based matrix-assisted laser desorption ionization time-of-flight mass spectrometry (culture-MS) method and real-time quantitative polymerase chain reaction (qPCR) assay. Results The CRISPR-GBS assay can be completed within 35 min and the limit of detection was as low as 5 copies μL−1. Compared with the culture-MS, the CRISPR-GBS assay demonstrated a sensitivity of 96.64% (144/149, 95% confidence interval [CI] 92.39–98.56%) and a specificity of 100% (30/30, 95% CI 88.65–100%). It also had a high concordance rate of 98.88% with the qPCR assay. Conclusions The established CRISPR-GBS platform can detect GBS in a rapid, accurate, easy-to-operate, and cost-efficient manner. It offered a promising tool for the intrapartum screening of GBS colonization.
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Péter, Mária, Wanda Török, Anna Petrovics-Balog, László Vígh, László Vécsei, and Gábor Balogh. "Cerebrospinal fluid lipidomic biomarker signatures of demyelination for multiple sclerosis and Guillain–Barré syndrome." Scientific Reports 10, no. 1 (October 27, 2020). http://dx.doi.org/10.1038/s41598-020-75502-x.

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Abstract Multiple sclerosis (MS) and Guillain–Barré syndrome (GBS) are demyelinating disorders affecting the central nervous system and peripheral nervous system (PNS), respectively. Cerebrospinal fluid (CSF) is one of the most valuable sources of diagnostic biomarkers in neurological diseases. In the present study high sensitivity shotgun mass spectrometry was used to characterise the CSF lipidome of patients with MS, GBS and controls with non-demyelinating diseases. The quantification of 222 CSF lipid molecular species revealed characteristic changes in the absolute and relative lipid concentrations in MS and GBS compared to the controls. For the GBS group, the fourfold elevation in the total lipid content was a discriminatory and a newly identified feature of PNS demyelination. In contrast, in MS, the accumulation of the myelin-derived cerebrosides represented a specific feature of demyelination. As a common feature of demyelination, we identified upregulated levels of lipid metabolic intermediates. We found strong positive correlation between total protein content and lipid concentrations in both diseases. By exploring the CSF lipidome we demonstrate usefulness of broad-range shotgun lipidomic analysis as a fast and reliable method of biomarker discovery in patients with demyelinating neurological disorders that might be a valuable diagnostic complement to existing examinations.
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Huang, Lianfen, Kankan Gao, Guanglian Chen, Huamin Zhong, Zixian Li, Xiaoshan Guan, Qiulian Deng, et al. "Rapid Classification of Multilocus Sequence Subtype for Group B Streptococcus Based on MALDI-TOF Mass Spectrometry and Statistical Models." Frontiers in Cellular and Infection Microbiology 10 (January 29, 2021). http://dx.doi.org/10.3389/fcimb.2020.577031.

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Group B Streptococcus (GBS) is an important etiological agent of maternal and neonatal infections as well as postpartum women and individuals with impaired immunity. We developed and evaluated a rapid classification method for sequence types (STs) of GBS based on statistic models with Matrix-Assisted Laser Desorption/Ionization Time-of Flight Mass Spectrometry (MALDI-TOF/MS). Whole-cell lysates MALDI-TOF/MS analysis was performed on 235 well-characterized GBS isolates from neonatal invasive infections in a multi-center study in China between 2015 and 2017. Mass spectra belonging to major STs (ST10, ST12, ST17, ST19, ST23) were selected for model generation and validation. Recognition and cross validation values were calculated by Genetic Algorithm-K Nearest Neighbor (GA-KNN), Supervised Neural Network (SNN), QuickClassifier (QC) to select models with the best performance for validation of diagnostic efficiency. Informative peaks were further screened through peak statistical analysis, ST subtyping MSP peak data and mass spectrum visualization. For major STs, the ML models generated by GA-KNN algorithms attained highest cross validation values in comparison to SNN and QC algorithms. GA-KNN models of ST10, ST17, and ST12/ST19 had good diagnostic efficiency, with high sensitivity (95–100%), specificity (91.46%–99.23%), accuracy (92.79–99.29%), positive prediction value (PPV, 80%–92.68%), negative prediction value (NPV, 94.32%–99.23%). Peak markers were firstly identified for ST10 (m/z 6250, 3125, 6891) and ST17 strains (m/z 2956, 5912, 7735, 5218). Statistical models for rapid GBS ST subtyping using MALDI-TOF/MS spectrometry contributes to easier epidemical molecular monitoring of GBS infection diseases.
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Jin, Mei, Jing Liu, Ziwei Zhao, Wenjin Geng, and Suzhen Sun. "Association Between A-Waves and Outcome in Pediatric Guillain-Barré Syndrome." Frontiers in Neurology 13 (June 17, 2022). http://dx.doi.org/10.3389/fneur.2022.914048.

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IntroductionTo examine the importance of abundant A-waves in electrophysiological classification and prognosis of pediatric Guillain-Barré Syndrome (GBS).MethodsA single-center and retrospective study enrolling 65 children-patients, aged 16 years and younger, with clinically diagnosed GBS between 2013 to 2020. Hughes grade was used to assess functional disability at nadir, 1 month, and 6 months after symptom onset. Patients were divided into 2 groups according to the presence of abundant A-waves. Clinical features and prognosis between the 2 groups were compared.ResultsThe distal motor latency of the median nerve in patients with GBS with A-waves (9.18 ms) was more prolonged than that of patients with GBS without A-waves (4.1 ms). An electrophysiological variant of these two groups was also statistically different (p = 0.006). The short-term prognosis of patients with AIDP with A-waves was worse than patients with AIDP without A-waves (χ2 = 5.022, p = 0.025), and univariable logistic regression analysis showed statistically significant (OR: 5.844, 95% CI 1.118–30.553; p = 0.036).ConclusionA-waves were strongly associated with demyelination and poor short-term prognosis of AIDP in children. We proposed an electrophysiological marker for early prediction of outcome in the AIDP subtype of GBS, applicable for clinical practice and future treatment administration.
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Chambers, Schuyler A., Rebecca E. Moore, Kelly M. Craft, Harrison C. Thomas, Rishub Das, Shannon D. Manning, Simona G. Codreanu, et al. "A Solution to Antifolate Resistance in Group B Streptococcus: Untargeted Metabolomics Identifies Human Milk Oligosaccharide-Induced Perturbations That Result in Potentiation of Trimethoprim." mBio 11, no. 2 (March 17, 2020). http://dx.doi.org/10.1128/mbio.00076-20.

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ABSTRACT Adjuvants can be used to potentiate the function of antibiotics whose efficacy has been reduced by acquired or intrinsic resistance. In the present study, we discovered that human milk oligosaccharides (HMOs) sensitize strains of group B Streptococcus (GBS) to trimethoprim (TMP), an antibiotic to which GBS is intrinsically resistant. Reductions in the MIC of TMP reached as high as 512-fold across a diverse panel of isolates. To better understand HMOs’ mechanism of action, we characterized the metabolic response of GBS to HMO treatment using ultrahigh-performance liquid chromatography–high-resolution tandem mass spectrometry (UPLC-HRMS/MS) analysis. These data showed that when challenged by HMOs, GBS undergoes significant perturbations in metabolic pathways related to the biosynthesis and incorporation of macromolecules involved in membrane construction. This study represents reports the metabolic characterization of a cell that is perturbed by HMOs. IMPORTANCE Group B Streptococcus is an important human pathogen that causes serious infections during pregnancy which can lead to chorioamnionitis, funisitis, premature rupture of gestational membranes, preterm birth, neonatal sepsis, and death. GBS is evolving antimicrobial resistance mechanisms, and the work presented in this paper provides evidence that prebiotics such as human milk oligosaccharides can act as adjuvants to restore the utility of antibiotics.
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Kronmüller, H., D. Goll, I. Kleinschroth, and A. Zern. "Hysteresis Loops and Coercivity Mechanisms in Sintered and Nanocrystalline Permanent Magnets." MRS Proceedings 577 (1999). http://dx.doi.org/10.1557/proc-577-303.

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ABSTRACTThe hysteresis loops of nanocrystalline (nc) permanent magnets (pms) produced by the melt-spin technique have been investigated for compositions based on the intermetallic compounds R2Fe14B (R = Nd, Pr) and the carbides Sm2Fe17−xGaxCy. The following three types of pms have been studied: 1) High-coercivity pins with exchange decoupled grains. 2) High-remanence exchange-spring pms. 3) High-coercive-high-remanence composite pins with exchange coupled soft and hard magnetic grains. The temperature dependence of the coercive field μ0Hc for all three types ofpms obeys a relation for a modified nucleation field, Hc = (2K1/Js)α - Neff Ms (K1 = first anisotropy constant, Ms = spontaneous magnetization). For an analysis of the characteristic differences between the microstructural parameters a and Neff as obtained for the three types of pms, computational micromagnetism on the basis of the Finite Element Technique is applied. This powerful method allows a quantitative analysis of the role of grain size, grain boundaries (gbs), texture of easy directions and of soft magnetic phases in composite materials. In order to obtain satisfactory results, a self-adapting algorithm has been developed where the mesh size is adapted to the gradients of the direction cosines of the spontaneous magnetization. It turns out that excellent magnetic properties of composite pms can only be obtained if the gbs are as ideal as possible. Remanence and coercive field are found to decrease linearly with a corresponding reduction of both, the crystal anisotropy and the exchange constant within the gbs. In composite pins the diameters of the soft magnetic grains should be smaller than twice the domain wall width, of the hard magnetic phase in order to obtain a remarkable remanence enhancement. From these model calculations general rules for the development of optimized nc pms with large remanences and large coercivities are derived.
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41

Jongihlati, Babalwa, Nathan Segall, Stanley Block, James Peterson, Judith Absalon, Samantha Munson, Yasmin Sanchez-Pearson, et al. "2134. A Phase 2 Study to Evaluate the Safety, Tolerability, and Immunogenicity of a Booster Dose of a Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6)." Open Forum Infectious Diseases 9, Supplement_2 (December 1, 2022). http://dx.doi.org/10.1093/ofid/ofac492.1755.

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Abstract Background Group B streptococcus (GBS) is a leading cause of invasive bacterial infections in young infants and pregnant women. Pfizer is developing a hexavalent GBS vaccine (GBS6) as a maternal vaccine to prevent invasive GBS disease due to the 6 most prevalent serotypes in young infants. We previously reported Phase 1 safety and immunogenicity data for GBS6. There is precedent for repeat doses of vaccines to augment or sustain circulating antibodies available for placental transfer with each pregnancy; thus, data to inform GBS6 booster strategies were required. Methods This was a Phase 2 open-label extension study to evaluate the safety and immunogenicity of a booster dose of GBS6 (20 μg capsular polysaccharide (CPS)/serotype/dose) with or without AlPO4, given ∼2 years after primary vaccination in 151 healthy nonpregnant adults. Sera taken before and 1-month postbooster were assessed for anti-CPS IgG using a direct Luminex immunoassay. Participants recorded solicited local and systemic events for 14 days after vaccination and unsolicited safety events through 6 months after vaccination. Immunogenicity time points from the Phase 1 study are referred to as primary dose. Results Immunogenicity results For all serotypes, serotype-specific IgG geometric mean concentrations (GMCs) remained elevated compared to baseline at the prebooster time point and were higher 1-month postbooster than 1 month post primary. The 1-month postbooster IgG GMCs were 10- to 59-fold higher than at the prebooster time point. There were similar responses between the 2 formulations. Safety and tolerability results The most frequently reported local reaction was mild to moderate pain at the injection site. Greater pain was associated with AlPO4 formulation. The most frequently reported systemic events were mild to moderate headache and fatigue. The frequency of adverse events was low. Figure 1Antibody Response Line Plot of IgG GMCs by Vaccine Group - All SerotypesFigure 2.Reverse Cumulative Distribution Curves (RCDCs) for IgG 1 Month After Primary and Booster Vaccination, by Vaccine Group – All SerotypesFigure 3.IgG Geometric Mean Fold Rises (GMFRs) at 1 Month Postbooster Vaccination Conclusion A booster dose of GBS6 given ∼2 years after a primary dose to healthy nonpregnant adults was safe and elicited robust immune responses that were also consistently higher than after primary dose. This study suggests that repeat vaccination with GBS6 may confer additional benefit in pregnant women in subsequent pregnancies. Disclosures Babalwa Jongihlati, MD, MBA, Pfizer: Stocks/Bonds Judith Absalon, MD, MPH, Pfizer: Stocks/Bonds Samantha Munson, MPH, MBA, Pfizer: Stocks/Bonds Yasmin Sanchez-Pearson, PhD, Pfizer: Stocks/Bonds Raphael Simon, PhD, Pfizer: Stocks/Bonds Natalie Silmon de Monerri, PhD, Pfizer: Stocks/Bonds David Radley, MS, Pfizer: Employee|Pfizer: Stocks/Bonds Emily A. Gomme, Ph.D., Pfizer: Stocks/Bonds Michelle Gaylord, PhD, Pfizer: Stocks/Bonds William C. Gruber, MD, Pfizer, Inc.: Salary|Pfizer, Inc.: Stocks/Bonds Kathrin U. Jansen, PhD, Pfizer: Stocks/Bonds Daniel A. Scott, MD, Pfizer: Employee|Pfizer: Stocks/Bonds Annaliesa S. Anderson, PhD, Pfizer: Stocks/Bonds.
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42

Boyce, B. L., L. N. Brewer, M. K. Neilsen, and M. J. Perricone. "On the Strain Rate- and Temperature-Dependent Tensile Behavior of Eutectic Sn–Pb Solder." Journal of Electronic Packaging 133, no. 3 (September 1, 2011). http://dx.doi.org/10.1115/1.4004846.

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The present study examines the thermomechanical strain-rate sensitivity of eutectic 63Sn–37Pb solder over a broad range of strain-rates from 0.0002 s–1 to 200 s–1, thus encompassing failure events between 1 h and 1 ms, at temperatures ranging from −60 °C to + 100 °C. A newly developed servohydraulic tensile method enabled this broad range of strain-rates to be evaluated by a single technique, eliminating ambiguity caused by evaluation across multiple experimental methods. Two solder conditions were compared: a normalized condition representing a solder joint that has largely stabilized ∼30 days after solidification and an aged condition representing ∼30 years at near-ambient temperatures. The tensile behavior of both conditions exhibited dramatic temperature and strain-rate sensitivity. At 100 °C, the yield strength increased from 5 MPa at 0.0002 s–1 to 42 MPa at 200 s–1, while at −60 °C, the yield strength increased from 57 MPa at 0.0002 s–1 to 71 MPa at 200 s–1. The room temperature strain rate-dependent behavior was also measured for the lead free SAC396 alloy. The SAC alloy exhibited thermal strain-rate sensitivity similar to Sn–Pb over this temperature and strain-rate regime. Microstructural characterization using backscatter electron imaging and electron backscatter diffraction showed distinct, morphological changes of the microstructure for different thermomechanical conditions as well as some systematic changes in the crystallographic texture. However, very little intergranular rotation was observed over the range of thermomechanical conditions, suggesting the dominance of a grain boundary sliding (GBS) deformation mechanism. Finally, a recently developed unified-creep-plasticity constitutive model for solder deformation was found to describe the observed behavior with much higher fidelity than the common Johnson–Cook model.
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