Journal articles on the topic 'Salt-load detection'

Mastitic milk was detected by obtaining conductance measurements using an impedance microbiology Bactomatic 120 SC instrument. Conductance readings separated normal and abnormal milks after 30 min at 25°C when readings differed by more than 2 to 3% and exceeded the variance among instrument module wells. Samples blended from four quarters of a cow indicated milk from one quarter was abnormal if the salt level in the abnormal quarter raised the blend conductivity above that of normal samples and variance among the wells. Either solid or liquid substrates that contained stimulants could be used to accelerate bacterial acid production or reduce impedance detection times and did not affect the ability to detect abnormal milk. However, measurements varied with the volume of sample in the well, suggesting that fixed 1-ml liquid volumes of milk be used. Such volumes would allow detection of abnormal milk and bacterial load on the same sample.

We demonstrate the use of resistivity/induced polarization (IP) monitoring of salt transport under natural hydraulic loads. Electrical monitoring of saline tracer transport during forced injection has been demonstrated previously. Detection of tracer transport under natural hydraulic loading is difficult because neither the hydraulic load nor the tracer resistivity can be controlled. In one study, we identify the electrical response to salt transport in a dynamic beach environment. Resistivity/IP imaging resolved the structure of the saltwater‐freshwater interface and evidence for tide‐induced groundwater transport. Resistivity increases in the near surface and at depth, upbeach of the high‐tide mark, accompanied by tidal transgression. We attribute this to desaturation and decreasing salinity in the near surface and to decreasing salinity at depth, despite tidal transgression. Monitoring of groundwater levels indicates a phase lag between the tide level and groundwater level, supporting the electrical data. IP was insensitive to groundwater salinity variation. In a second study, we identify the electrical response to recharge‐induced salt transport from a road‐salt storage facility. Conductivity and IP models for monitoring lines, located on the basis of an EM31 survey, resolved the subsurface salt distribution. IP modeling resolved the sediment‐bedrock interface. Modeling of monthly conductivity differences revealed conductivity increases and decreases at the locations of salt contamination, which correlate with the recharge pattern. We attribute near‐surface conductivity increases after heavy rainfall to increasing saturation and ion dissolution. Corresponding conductivity decreases at depth are attributed to flushing of the bedrock with freshwater. Essentially, the opposite response was observed during a quiet monitoring period following heavy recharge. Near‐surface IP changes are consistent with this interpretation. Salt transport occurring under natural hydraulic conditions was monitored with resistivity imaging. IP improved characterization of the hydrogeologic framework but was of limited value in monitoring salt transport in these environments.

Abstract There is evidence that Staphylococcus aureus colonisation is linked to severity of atopic dermatitis. As no gold standard for S. aureus sampling on atopic dermatitis skin lesions exists, this study compared three commonly used methods. In addition, effectiveness of standard skin disinfection to remove S. aureus colonisation from these inflamed skin lesions was investigated. In 30 atopic dermatitis patients, three different S. aureus sampling methods, i.e. detergent scrubbing, moist swabbing and tape stripping, were performed on naïve and disinfected skin lesions. Two different S. aureus selective media, mannitol salt agar and chromID agar, were used for bacterial growing. Quantifying the S. aureus load varied significantly between the different sampling methods on naïve skin lesions ranging from mean 51 to 1.5 × 104 CFU/cm2 (p < 0.001). The qualitative detection on naïve skin was highest with the two detergent-based techniques (86% each), while for tape stripping, this value was 67% (all on chromID agar). In comparison, mannitol salt agar was less sensitive (p < 0.001). The disinfection of the skin lesions led to a significant reduction of the S. aureus load (p < 0.05) but no complete eradication in the case of previously positive swab. The obtained data highlight the importance of the selected sampling method and consecutive S. aureus selection agar plates to implement further clinical studies for the effectiveness of topical anti-staphylococcal antibiotics. Other disinfection regimes should be considered in atopic dermatitis patients when complete de-colonisation of certain skin areas is required, e.g. for surgical procedures.

In an effort to find a rapid, efficient, and reliable method of screening large numbers of bacterial isolates for specific antimicrobial resistance genes, we compared conventional PCR results to the results generated using the TaqMan 5′ nuclease PCR kit in conjunction with an ABI Prism 7700 Sequence Detector for detecting themecA gene in various species of staphylococci. DNA was extracted using two techniques. The first used a high-salt extraction method suitable for conventional PCR but resulted in a 7.2% rate of PCR inhibition with the TaqMan technique. PCR inhibition could be overcome by diluting samples 1:5 prior to testing. The second method used the Qiagen QIAamp Tissue Kit; no instances of PCR inhibition were encountered with this method. A total of 197 (96%) of the 206 samples with no inhibition showed agreement between the two methods. Eight of the nine disagreements were likely the result of low-level DNA cross contamination caused by frequent specimen handling. Target DNA in all eight of these samples was first detected in the initial tests only after >30 PCR cycles, and all were negative upon repeat testing even after 40 PCR cycles using freshly extracted DNA. Among those positive samples in agreement, target DNA was invariably detected before 30 PCR cycles. The TaqMan assay eliminated the need to load, run, stain, and read agarose gels and provided the advantage of instant detection of PCR product by laser-activated fluorescence. Thus, final results were obtained 2 h after PCR was initiated, as opposed to a requirement of 2 days to examine 96 samples by agarose gel electrophoresis.

Abstract Background: Extraction protocols using magnetic solid phases offer a high potential for automation. However, commercially available magnetic-bead–based assays either lack the sensitivity required for viral diagnostics or are disproportionately expensive. Methods: We developed an aqueous chemistry for extraction of viral nucleic acids from plasma samples by use of common magnetic silica beads. Nucleic acids were bound to the beads at acidic conditions in the presence of a kosmotropic salt and were eluted at a slightly alkaline pH. The method was implemented on a standard pipetting workstation for fully automated extraction of up to 48 samples of 240 μL plasma in 1 batch. Results: The detection limit of the method was comparable to the spin-column–based QIAamp Viral RNA Mini Kit, which relies on chaotropic salts and binding to a silica membrane, as the comparison method. The 95% detection limit was 23.1 IU per PCR for HIV-1 and 10.7 IU per PCR for hepatitis C virus (HCV). Suitability for clinical routine testing was confirmed in a total of 178 HIV-1- or HCV-positive plasma samples. The method linearity (R2) was &gt;0.99 for the viruses evaluated. Conclusions: Use of reagents without organic solvents allows simple and cost-effective automation of this method on common pipetting robots with low risk of contamination. Performance characteristics of the novel extraction method make it suitable for use in diagnosis of infectious diseases and viral load determinations.

Microorganisms grow on meat causing visual, textural and organoleptic changes when they release metabolites. A lot of factors affect the growth of microorganisms on meat, which include temperature, pH, water availability, presence of nutrients, gaseous requirement and atmosphere of storage. Microbial quality of raw meat and tsire sold at retail outlets from Yayari, Yankoli and Matsaro of Hadejia metropolis, Jigawa State were evaluated. Three samples from each outlet were collected fortnightly into sterile plastic bags, stored at 4°C in ice chest filled with ice and transported immediately to the laboratory for Total Viable Count (TVC), Total Coliform Count (TCC), Total Staphylococcus Count (TCS) and Total Fungal Count (TFC) analyses using Nutrient Agar, Mac Conkey Agar, Mannitol Salt Agar and Potato Dextrose Agar, respectively. They were incubated at 37°C for 24 hours except for the detection of fungi, which was incubated at 25°C for 5 days. Tsire samples collected from Matsaro had the highest TVC (6.0 x 104) while that from Yankoli had the highest TCS (4.0x102). The study concluded that tsire sold at Hadejia Local Government Area was safe for consumption, due to its less microbial load.

The objective of this study is to measure the amounts of biogenic amines, microbial counts, values of pH, titratable acidity, dry matter, and salt (%) in herby cheese, a very popular staple in the Turkish diet, and to evaluate the concentration of biogenic amines in terms of public health risks. A high-performance liquid chromatography (HPLC) method was used for the determination of eight biogenic amines in 100 herby cheeses sold in the local markets of Van. The bacterial load of the herby cheeses ranged between 4.0 and 8.90 log CFU/g for viable total aerobic mesophilic bacteria (TAMB), <1 and 7.0 log CFU/g for lactic bacteria (LAB), <1 and 6.08 log CFU/g for coliform bacteria, <1 and 5.81 log CFU/g for Enterobacteriaceae, <1 and 2.60 log CFU/g for Staphylococcus aureus, and 3.70 and 8.05 log CFU/g for yeasts and molds. The results obtained suggested significant changes in the pH, titratable acidity, dry matter, and salt contents of the examined herby cheese samples. The detection levels of biogenic amines in the samples ranged from <0.025 to 33.36 mg/kg for tryptamine, from <0.038 to 404.57 mg/kg for β-phenylethylamine, from 0.03 to 426.35 mg/kg for putrescine, from <0.039 to 1438.22 mg/kg for cadaverine, from <0.033 to 469 mg/kg for histamine, from <0.309 to 725.21 mg/kg for tyramine, from <0.114 to 1.70 mg/kg for spermidine, and from <0.109 to 1.88 mg/kg for spermine. As a result, these cheeses are fit for consumption in terms of the amounts of biogenic amines they contain.

Abstract Background Respiratory Syncytial Virus (RSV) is the most common cause of bronchiolitis and pneumonia in infants and children. Diagnosis of RSV can be made by molecular detection of the virus in a swab of respiratory secretions. Nasopharyngeal (NP) swabs are the most frequent swab type validated for the detection of RSV, and are often considered the “gold standard” for quantification studies. However, NP sampling is invasive and uncomfortable. We sought to determine whether a less invasive method, a mid-turbinate (MT) swab, was comparable to NP sampling for quantification of RSV in infants. Methods We prospectively enrolled children &lt; 24 months with a confirmed diagnosis of RSV and hospitalized at Primary Children’s Hospital (Salt Lake City, UT) during the 2015 – 2017 RSV seasons. Both an NP and MT swab were collected from each infant from different nostrils; subjects were randomized (1:1:1:1) as to the order of collection. After collection, parents were asked which collection method (NP vs. MT) they preferred. Viral loads were measured by real-time RT-qPCR. Correlation between the viral loads from the MT and NP swabs was examined. A mixed effect model was used to evaluate the mean (SD) viral loads. Results 83 infants were enrolled and had swabs collected. Median age was 4 months [range 0–23]. 20 infants had swabs collected on multiple consecutive days. Median (Q1,Q3) duration of symptoms prior to enrollment was 5 days (4,7) Median (Q1,Q3) hospital stay length was 2 days (2,4). 1 infant was RSV negative according to the RT-qPCR assay. The mean (SD) viral loads were similar: 7.34 (1.26) and 7.09 (1.25) log10 copies/mL for 77 paired NP and MT swabs, respectively; see Figure 1 for median, range and quartiles. The correlation coefficient between the paired viral loads was high (0.82); see Figure 2 for Bland-Altman plot. Most parents (49/67 [73%]) who watched the swabbing preferred the MT to the NP swab. Conclusion MT swabs perform as well as NP swabs for the quantification of RSV in infants. The difference in mean viral load is small compared with the standard deviation. The less invasive MT swabs are preferred by parents for sampling. MT swabs have the potential to replace the NP swab as the “gold standard” for quantitative respiratory viral sampling. Disclosures A. J. Blaschke, Gilead Sciences, Inc: Investigator, Research support BioFire Diagnostics, LLC: Collaborator, I have intellectual property in BioFire Diagnostics through the University of Utah and Investigator, Licensing agreement or royalty and Research support

In this study, 45 (10 whole specimens and 35 frozen claws) frozen samples of Portunus pelagicus imported into Sicily (Italy) from the west coast of Africa were examined to assess their bacteriological characteristics and suitability for consumption. Bacteriological examination was performed on two subsamples for each whole crab. The first was the body and claw muscle; the second was a pool of viscera and gills. In the case of frozen claws, each muscle claw was a sample. An aerobic plate count at 30°C (mesophilic aerobic plate count [MAPC]) and 18°C (psychrotrophic aerobic plate count [PAPC]) for 3 days, sulfite-reducing anaerobes, total coliforms, Escherichia coli, enterococci, and Aeromonas spp. were enumerated. Detection of halophilic Vibrio spp. was also performed using salt polymixin broth as an enrichment medium and thiosulfate citrate bile salts sucrose agar as a selective medium; a further morphological and biochemical identification of suspected colonies was performed. The bacterial load of muscle and viscera and gills was low. The MAPC ranged from 0.78 to 3.26 log CFU/g, and the PAPC ranged from 0.48 to 2.41 log CFU/g. Vibrio spp., Aeromonas spp., sulfite-reducing anaerobes, and E. coli were never isolated from muscles or viscera and gills. In contrast to the findings of others, this study showed good bacteriological quality of crabs imported into Sicily from the west coast of Africa. This study also demonstrated the positive influence of the characteristics of environment of origin and postharvest handling hygiene; these parameters could be useful in the context of the application of the hazard analysis critical control point system to this production.

Microflora plays an important role in modulating environmental quality. Among microflora, bacteria are omnipresent in the environment. Pathogenic bacteria, present in air, are known to affect significantly the health and well-being of human, animal or plant populations. Air bacteria monitoring is thus essential for surveillance of pathogenic microorganisms from public health perspective besides its significant implications in detection and mitigation of biothreat related issues. Despite the geo-politically strategic importance of northeast India, there is scarcity of data on human health and disease surveillance. Considering these facts, we, for the first time studied the bacterial diversity of air at six important sites adjacent to the international border in the northeast region of India, having an altitude range of 73 m (Tezpur) to 4170 m (Sela Pass) above sea level. Standard microbiological techniques, such as Tryptone Soya Agar, Mannitol salt and McConkey agar strips and plates were used for air bacterial load assessment and culture for subsequent analysis using biochemical and molecular techniques. Following RFLP study, twenty six different bacterial colonies were isolated. Subsequently, bacteria identification was carried out by examining the substrate utilisation patterns, sequencing 16S rRNA gene and phylogenetic analysis. Results of the study reveal that the isolates mostly belong to two genera Bacillus and Staphylococcus (eleven in each genus), along with Micrococcus, Pseduomonas and Acinetobacter. Based on significant match of our sequences with that of medically important bacterial 16S rRNA sequences available at 16SpathDB 2.0 and review of available literature, we found that a number of these bacterial species have the pathogenic potential. In this manuscript we report our results and discuss the importance of air bacterial surveillance from the perspective of human health, hygiene and biothreat mitigation.

Arterial hypertension (AH) is a leading risk factor for the development of cardiovascular, cerebrovascular, and renal diseases, which are among the top 10 most common causes of death in the world. The etiology of hypertension has not been fully elucidated, but it has been established that endothelial dysfunction is the most significant pathogenetic link in the formation and progression of the disease. The data obtained in the last 10-15 years on endothelial glycocalyx (eGC) studies indicate that endothelial dysfunction is preceded by destabilization and shedding of eGC with the appearance of its soluble components in the blood, which is equivalent to a process that can be designated as eGC dysfunction. Signs of eGC dysfunction are expressed in the development of hypertension, diseases of the cardiovascular system, and their complications. The purpose of this review is to analyze and substantiate the pathophysiological role of eGC dysfunction in hypertension and cardiovascular diseases and to describe approaches for its assessment and pharmacological correction. Abstracts and full-size articles of 425 publications in Pubmed/MEDLINE databases over 20 years were studied. The review discusses the role of eGC in the regulation of vascular tone, endothelial barrier function, and anti-adhesive properties of eGC. Modifications of eGC under the influence of pro-inflammatory stimuli, changes in eGC with age, and with increased salt load are considered. The aspect associated with eGC dysfunction in atherosclerosis, hyperglycemia and hypertension is covered. Assessment of eGC dysfunction is difficult but can be performed by indirect methods, in particular by detecting eGC components in blood. A brief description of the main approaches to pharmacoprevention and pharmacocorrection of hypertension is given from the position of exposure effects on eGC, which currently has more a fundamental than practical orientation. This opens up great opportunities for clinical studies of eGC dysfunction for the prevention and treatment of hypertension and justifies a new direction in the clinical pharmacology of antihypertensive drugs.

AbstractThe importance of monitoring environmental samples has gained a lot of prominence since the onset of COVID-19 pandemic, and several surveillance efforts are underway using gold standard, albeit expensive qPCR-based techniques. Electrochemical DNA biosensors could offer a potential cost-effective solution suitable for monitoring of environmental water samples in lower middle income countries. In this work, we demonstrate electrochemical detection of amplicons as long as $${503}\,\hbox {bp}$$ 503 bp obtained from Phi6 bacteriophage (a popular surrogate for SARS-CoV-2) isolated from spiked lake water samples, using ENIG finish PCB electrodes with no surface modification. The electrochemical sensor response is thoroughly characterised for two DNA fragments of different lengths ($${117}\,\hbox {bp}$$ 117 bp and $${503}\,\hbox {bp}$$ 503 bp ), and the impact of salt in PCR master mix on methylene blue (MB)-DNA interactions is studied. Our findings establish that length of the DNA fragment significantly determines electrochemical sensitivity, and the ability to detect long amplicons without gel purification of PCR products demonstrated in this work bodes well for realisation of fully-automated solutions for in situ measurement of viral load in water samples.

Objective: The current study aims to boost the bioavailability criteria of two natural bioactive compounds, andrographolide and curcumin by their combination in nanostructured lipid carrier (NLC) and also to develop a straightforward reverse-phase high-performance liquid chromatography (RP-HPLC) method to validate, quantify of andrographolide and curcumin simultaneously in novel NLC formulation. Methods: The reliable chromatographic separation was executed by using a column of Phenomenex octadecylsilane (C18) at 35 °C column oven temperature using a mobile phase of 0.02 M potassium dihydrogen orthophosphate (KH2PO4) salt solution of pH 3.0 as a buffer and acetonitrile in 50: 50 v/v fixed ratio and 1.5 ml/min flow rate of with 20 μl injection load. The detection was carried out at 240 nm isosbestic wavelength employing a photodiode array (PDA) detector. Results: Andrographolide and curcumin were eluted at 2.4 and 4.9 min, respectively. Quantification and linearity were achieved for both drugs at the 10-140 μg/ml range. The method is specified as the presence of excipients utilized in the formulation failed to interfere with the estimation of andrographolide and curcumin. The developed method was successfully utilized to work out the drug loading efficiency and in vitro drug release study of those drugs in NLC formulation and also for the estimation of those drugs from rat plasma. Conclusion: The developed high-performance liquid chromatography (HPLC) method may be utilized in the future estimation of andrographolide and curcumin simultaneously in NLC and other nanoformulations both in vitro and in vivo.

Abstract in the June Abstracts issue of Clinical Chemlstrytwo abstracts were mistakenly marked as withdrawn. The two abstracts that appear below were presented during the 1987 AACC National Meeting. 038 Clinical Evaluation of Quantitative Serum Bata-HCG Inoausays:Analysis of Discordant Beta-HCG Results, Norman J. kruse* Bonnie Johnson, and Ruth Lee** (Medlab, Portland, OR 97212) (Spon. N.J.kruse) Clinical evaluation of 4 commercial serum beta-HCG methods (Abbott, American Bioclinical, and Hybritech) were prformed using patient specimens predominantly for pregnancy determinations and related conditions. Discordant results were analysed at least twice in each method and additional serum specimens from the patient were obtainedand analysed in most cases of discordance. All methods were analysed for precision, sensitivity, cross-reactivity with homologous hormenes, and for effects of hemolysis and lipemia. Standardization and sensitivity differences between assays were determined. Reproducible, clinically significant discordant beta-HCG results were identified that were unrelated to standardization or sensitivity differences, LH cross-reactivity; or obvious serum matrix differences. These discordant results were stable, low-level (25-200 mIU/ml HCG)false positives with no evidence of pregnancy, trophoblastic disease or HCG-secreting malignancy (cf. R.0. Hussa, Obstet, S Gynecol, 65, 211, 1985). The rate of occurence of these patients was approximately 0.5% in our analysis of over 2000 patients with 2 competitive binding immunoassays using highly-specific polyclonal or monoclonal antibodies. Immunoassays using Immunoradiometric (IRMA) or ELISA "sandwich" assay technology showed lower false positive rates. One false-positive result in the ELISA assay (Abbott) was observed apparently due to rhematoid factor. No false-positive results were observed in the Hybritech IRMA using monoclonal antibodies. Stable low-levelfalse positive beta-HCG results can be a relatively rare, but significant problem in some beta-HCG methods. Our analysis of 2 methods using "sandwich" immunoassay technology (IRMA or ELISA) revealed that the occurence of these results can be greatly reduced or eliminated. *Present address: Triton Biosciences. Alameda, California **present address: Epitope, Beaverton, Oregon 97006 177 AFFINITYTM SYSTEM: TOTAL AUTOMATED DIAGNOSTIC TESTING WITH RANDOM ACCESS CAPABILITY, T.R. Witty, H.L. Larriva, M.E. Asti11 and G.H. Thorne, (becton Dickinson, Salt Lake City, Utah, 84116) (Spon: T.R. Witty) Becton Dickinson's AFFINITYTM system is a non-isotopic, automated. bench-top in vitro diagnostic instrument. The key element is the ready-to-use reagent package called an ImmUnitTM (patent 4608231) for immunoassays, identified by a unique barcode for each teat as well as a specific identifier for each unit. This ideatification is coupled with a scheduling algorithm which allows for any test with up to 3 incubations of varyine time to be run in any combination. A test is started by loading the tray with the desired test Unit(s) whereupon the instrument loads the Unit(s) onto the internal carousel for inventory and processing. The entire run is prioritized and scheduled including both STAT and routine samples. Up to 30 separate Units can be resident on the carousel. at any time with 16 more awaiting loading. Each time loading occurs, the run is updated and scheduled. By careful control of fluid handling and complete washing, each assay is independent of other assays. This eliminates load scheme restriction. The system can detect either fluorescence or color directly in the l2mm tube present in each test unit and internally correct for tube variation. This premise was tasted by running each of dieoxin, hTSH, TUptake and hCG in the presence and absence of 2 other tests then comparing the baseline with the random loaded run. The observed mean of 3 test pools when run in the presence of the other analytes was 99.7% +/- 4.1% of expected (N-12). The observed precision range on the baseline run was from 0.8-9.2% CV. mean=3.7% (N=12) while random was 1.5-9.1% CV, mean=4.5% (n=12). No significant differences were observed. The combination of the unitized package, barcode initiated scheduling algorithm and fluorescence/ooloriometrtc detection leads to a unique and flexible bench-top device compatible with a variety of diagnostic tests.