Articoli di riviste: "Iso-electric focusing"

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Wangoh, J., Z. Farah e Z. Puhan. "Iso-electric Focusing of Camel Milk Proteins". International Dairy Journal 8, n. 7 (luglio 1998): 617–21. http://dx.doi.org/10.1016/s0958-6946(98)00092-2.

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YOKOHAMA, Michinari, Yasuko WATANABE e Kazushige MOGI. "A New Equine Transferrin Phenotype Detected by Iso-electric Focusing". Nihon Chikusan Gakkaiho 56, n. 2 (1985): 116–21. http://dx.doi.org/10.2508/chikusan.56.116.

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Hawkes, Christopher H., Edward J. Thompson, Geoffrey Keir, John Elston, Mahboub Hawkes, Robert Lamb e Simon Ruben. "Iso-electric focusing of aqueous humour IgG in multiple sclerosis". Journal of Neurology 241, n. 7 (1994): 436–38. http://dx.doi.org/10.1007/bf00900962.

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Menegatti, Marcello, Dino Vaira, John Holton, Fernanda Miranda, Chiara Ricci, Riccardo Gusmaroli, Colin Ainley, Mario Miglioli e Luigi Barbara. "Serological Response to Helicobacter Pylori in Gastric and Non—Gastric Cancer". Clinical Science 91, n. 2 (1 agosto 1996): 219–23. http://dx.doi.org/10.1042/cs0910219.

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1. We aimed to evaluate the seroprevalence of Helicobacter pylori (H. pylori) in gastric cancer, non-gastric cancer and outpatients by ELISA and isoelectric focusing, and to compare histology and serology for H. pylori in gastric cancer and outpatients. 2. In 124 patients with gastric cancer, 78 patients with non-gastric cancer and 110 outpatients, H. pylori seroprevalence was assessed by ELISA and isoelectric focusing. Gastric cancer and outpatients underwent endoscopy with biopsies. 3. Seroprevalence by ELISA was significantly higher in gastric cancer compared with non-gastric cancer (84% versus 56%, P < 0.001) but not with outpatients (84% versus 74%). Iso-electric focusing detection of H. pylori was comparable to ELISA: 85, 51 and 75% in gastric cancer, non-gastric cancer and outpatients respectively. Oligoclonal iso-electric focusing was significantly more frequent in gastric cancer compared with non-gastric cancer and outpatients: 69% versus 45 and 46% respectively, P < 0.01. The reliability of H. pylori detection by antral biopsy was significantly lower in gastric cancer compared with outpatients: 36% versus 74% (P < 0.001). In gastric cancer, ELISA and iso-electric focusing were significantly more reliable than histology in H. pylori detection (84 and 85% versus 36% respectively) (P < 0.001). 4. Serological immune response to H. pylori in gastric cancer, non-gastric cancer and outpatients seems different both quantitatively and qualitatively; serology was more reliable than histology in detection of H. pylori in gastric cancer.

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Kumar, Mahendra, Bijay P. Tripathi e Vinod K. Shahi. "Electro-membrane process for the separation of amino acids by iso-electric focusing". Journal of Chemical Technology & Biotechnology 85, n. 5 (maggio 2010): 648–57. http://dx.doi.org/10.1002/jctb.2348.

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Freeman, Amanda N. D., e Peter J. Smith. "Iso‐electric focusing and the identification of fisheries’ waste in the diet of Westland petrels (Procellaria westlandica)". New Zealand Journal of Marine and Freshwater Research 32, n. 2 (giugno 1998): 177–80. http://dx.doi.org/10.1080/00288330.1998.9516817.

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Andersson, Leif, Sven Bengtsson, Ulf Hellman, Ivan Källman e Camilla Ranje. "Genetic variation of haemoglobin α- and βchains in rabbits detected by iso electric focusing and reversed-phase chromatography". Animal Blood Groups and Biochemical Genetics 16, n. 1 (24 aprile 2009): 41–50. http://dx.doi.org/10.1111/j.1365-2052.1985.tb01450.x.

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Ito, A., A. Plancarte, M. Nakao, K. Nakaya, T. Ikejima, Z. X. Piao, T. Kanazawa e S. S. Margono. "ELISA and immunoblot using purified glycoproteins for serodiagnosis of cysticercosisin pigs naturally infected with Taenia solium". Journal of Helminthology 73, n. 4 (aprile 1999): 363–65. http://dx.doi.org/10.1017/s0022149x9900061x.

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The establishment of reliable serological methods for cysticercosis in pigs is important for the surveillance, control and prevention of taeniosis/cysticercosis in humans as well as in pigs to prevent economic loss. Both ELISA and immunoblot using glycoproteins (GPs) purified by a single step of preparative iso-electric focusing, which are highly useful for human cysticercosis, have been applied for a serological study in pigs naturally infected withTaenia solium. All sera from pigs showed similar responses to those in human cysticercosis. Therefore, it is expected that both ELISA and immunoblots using GPs would be useful in differentiating infected pigs from uninfected ones.

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Loughran, Michael, Shuo-Wen Tsai, Kenji Yokoyama e Isao Karube. "Simultaneous iso-electric focusing of proteins in a micro-fabricated capillary coated with hydrophobic and hydrophilic plasma polymerized films". Current Applied Physics 3, n. 6 (dicembre 2003): 495–99. http://dx.doi.org/10.1016/j.cap.2003.09.002.

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Kourtis, Athena, G. A. Pangalis, L. Borche, Viki A. Boussiotis, G. Dighiero e Peggy Lymberi. "Monoclonal and/or Oligoclonal Immunoglobulins in Sera of Patients with Non-Hodgkin's Lymphomas, Determined by Iso-Electric Focusing and Immunoblotting". Leukemia & Lymphoma 5, n. 4 (gennaio 1991): 255–62. http://dx.doi.org/10.3109/10428199109068135.

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Ciller, U. A., I. M. Ciller e J. R. McFarlane. "277. Equine chorionic gonadotrophin isoform composition in commercial products compared with isoform composition in pregnant mare plasma". Reproduction, Fertility and Development 20, n. 9 (2008): 77. http://dx.doi.org/10.1071/srb08abs277.

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It is well documented that there is considerable batch to batch variation in the activity of commercial preparations of gonadotrophins. These products are used in a variety of assisted reproductive procedures in the livestock industry, consequently this high degree of variation between products and batches adds to the already considerable between animal variations in response to the treatment. Equine chorionic gonadotrophin (eCG) is a heterodimeric glycoprotein hormone secreted by the placental endometrial cups during the first third of gestation in the horse. Plasma is harvested from pregnant mares between 40–90 days of gestation and the eCG isolated and used to formulate commercial preparations. Previous research has shown that eCG like the other gonadotrophins is a highly heterogeneous molecule with significant differences in bioactivity between isoforms. The aim of this study was to determine whether significant differences in isoform composition exist between various commercial preparations of eCG (n = 15), and how this compares with the isoform composition found in plasma (n = 23). Concentrations of eCG were determined using a competitive eCG ELISA. Liquid phase iso-electric focusing was used to fractionate plasma and the commercial preparations into 10 pH ranges from pH 3.0 to pH 10.0. Data from the 10 fractions were grouped into acidic (pH 3.0–5.1), intermediate (pH 5.2–7.9), or basic (pH 8.0–10.0) isoform categories for analysis. Immunoactivity between commercial eCG products ranged from 44% to 362% of stated bioactivity. Iso-electric focusing showed that the majority of the immunoactivity (92%) of the commercial preparations was found in the acidic fractions (pH 3.0–5.1), and in particular in the pH range 3.0–3.8. This contrasted starkly with isoform profiles found in pregnant mare plasma samples which showed a much greater spread across all 3 pH ranges. In summary, the isolation processes of commercial eCG preparations appears to selectively favour the acidic isoforms of eCG.

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SOUNART, T. L., e J. C. BAYGENTS. "Lubrication theory for electro-osmotic flow in a non-uniform electrolyte". Journal of Fluid Mechanics 576 (28 marzo 2007): 139–72. http://dx.doi.org/10.1017/s0022112006003867.

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A lubrication theory has been developed for the electro-osmotic flow of non-uniform buffers in narrow rectilinear channels. The analysis applies to systems in which the transverse dimensions of the channel are large compared with the Debye screening length of the electrolyte. In contrast with related theories of electrokinetic lubrication, here the streamwise variations of the velocity field stem from, and are nonlinearly coupled to, spatiotemporal variations in the electrolyte composition. Spatially non-uniform buffers are commonly employed in electrophoretic separation and transport schemes, including iso-electric focusing (IEF), isotachophoresis (ITP), field-amplified sample stacking (FASS), and high-ionic-strength electro-osmotic pumping. The fluid dynamics of these systems is controlled by a complex nonlinear coupling to the ion transport, driven by an applied electric field. Electrical conductivity gradients, attendent to the buffer non-uniformities, result in a variable electro-osmotic slip velocity and, in electric fields approaching 1 kV cm−1, Maxwell stresses drive the electrohydrodynamic circulation. Explicit semi-analytic expressions are derived for the fluid velocity, stream function, and electric field. The resulting approximations are found to be in good agreement with full numerical solutions for a prototype buffer, over a range of conditions typical of microfluidic systems. The approximations greatly simplify the computational analysis, reduce computation times by a factor 4–5, and, for the first time, provide general insight on the dominant fluid physics of two-dimensional electrically driven transport.

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Bartkowiak, Tomasz, Michał Mendak, Krzysztof Mrozek e Michał Wieczorowski. "Analysis of Surface Microgeometry Created by Electric Discharge Machining". Materials 13, n. 17 (30 agosto 2020): 3830. http://dx.doi.org/10.3390/ma13173830.

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The objective of this work is to study the geometric properties of surface topographies of hot-work tool steel created by electric discharge machining (EDM) using motif and multiscale analysis. The richness of these analyses is tested through calculating the strengths of the correlations between discharge energies and resulting surface characterization parameters, focusing on the most representative surface features—craters, and how they change with scale. Surfaces were created by EDM using estimated energies from 150 to 9468 µJ and measured by focus variation microscope. The measured topographies consist of overlapping microcraters, of which the geometry was characterized using three different analysis: conventional with ISO parameters, and motif and multiscale curvature tensor analysis. Motif analysis uses watershed segmentation which allows extraction and geometrically characterization of each crater. Curvature tensor analysis focuses on the characterization of principal curvatures and their function and their evolution with scale. Strong correlations (R2 > 0.9) were observed between craters height, diameter, area and curvature using linear and logarithmic regressions. Conventional areal parameter related to heights dispersion were found to correlate stronger using logarithmic regression. Geometric characterization of process-specific topographic formations is considered to be a natural and intuitive way of analyzing the complexity of studied surfaces. The presented approach allows extraction of information directly relating to the shape and size of topographic features of interest. In the tested conditions, the surface finish is mostly affected and potentially controlled by discharge energy at larger scales which is associated with sizes of fabricated craters.

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Shanahan, P. M. A., C. J. Thomson e S. G. B. Amyes. "β-Lactam resistance in normal faecal flora from South Africa". Epidemiology and Infection 115, n. 2 (ottobre 1995): 243–53. http://dx.doi.org/10.1017/s0950268800058374.

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SummaryThe genetic and biochemical basis of ampicillin resistance amongst the aerobic Gram-negative commensal faecal flora of healthy volunteers in South Africa has been determined. Amongst 608 ampicillin resistant strains isolated from 320 of the participants, 158 were able to transfer their ampicillin resistant determinants intoEscheriehia coliK-12 J62–2. Iso-electric focusing of the β-lactamases, extracted from the transconjugants, demonstrated that ampicillin resistance resulted from the presence of the TEM-1, TEM-2 and SHV-1 β-lactamases in 94·3%, 2·5% and 3·2% of isolates respectively. Endonuclease restriction digests of the plasmids isolated from the transconjugants showed that the β-lactamase genes were present on a wide variety of plasmid types; 101 distinct plasmid endonuclease restriction patterns were identified. Transferable ampicillin resistance was associated with resistance to other antibiotics at the following frequencies: trimethoprim (48·7 %), streptomycin (35·4 %), tetracycline (27·2%), spectinomycin (9·5%), chloramphenicol (3·2%) and gentamicin (1·3%). One antibiotic resistance pattern, ampicillin and trimethoprim. predominated (28%). In total. 77·9% of the plasmids conferred resistance to other antibiotics raising the possibility that use of any of these agents, not simply ampicillin, may contribute to the maintenance of resistance genes.

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Siew, Ye Wee, Karina Listiarini Zedda e Svetlozar Velizarov. "Nanofiltration of Simulated Acid Mine Drainage: Effect of pH and Membrane Charge". Applied Sciences 10, n. 1 (5 gennaio 2020): 400. http://dx.doi.org/10.3390/app10010400.

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Acid mine drainage (AMD) is a severe form of environmental pollution that has the potential to contaminate surface and ground waters by introducing heavy metals and lowering the pH. The feasibility of using nanofiltration (NF) as a potentially attractive and cost-effective remediation method to treat acid mine drainage was investigated in this study. The performance of an acid-stable NF membrane focusing on the effects of the water pH and membrane charge on ion rejection was systematically studied. A single salt solution experiment showed that Mg, Cu, and Mn containing species were highly rejected at above 97%. Below the membrane iso-electric point (IEP), Mn showed an increased rejection of 99%, while Mg and Mn rejections were relatively constant within the investigated pH range of pH 2 to 7. Rejection of monovalent Cl− decreased with increasing concentration of an accompanying divalent SO42−, showing that Donnan related effects are more prominent at higher ionic concentrations. The sulfate rejection decreased drastically below pH 3 due to the formation of HSO4−, which permeated through the membrane, which can be utilized as a way of separation of the metals from the accompanying sulfur-containing compounds. For mixed salt solutions, rejection of silicate dropped from 52% to 38% when magnesium sulfate was added, owing to shielding of the membrane surface charge by Mg2+ ions. The NF process performance with a simulated AMD solution was found to be similar to that with model salt solution experiments, both in terms of ion rejection values and general pH-dependent rejection trends. The results obtained can be used as a fast preliminary tool for evaluating the feasibility of using NF for treating AMD with a given ionic composition and pH.

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Streetly, Allison, Mary Clarke, Melanie Downing, Lisa Farrar, Ying Foo, Kate Hall, Helena Kemp et al. "Implementation of the newborn screening programme for sickle cell disease in England: results for 2003-2005". Journal of Medical Screening 15, n. 1 (marzo 2008): 9–13. http://dx.doi.org/10.1258/jms.2008.007063.

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Objectives This paper reports early screening results from the newborn sickle cell disease screening programme recently implemented in England. Setting England. Screening is offered at 5-8 days of age as part of the existing bloodspot test and offered to all babies irrespective of ethnicity. Methods The laboratory methods recommended are high performance liquid chromatography (HPLC) and iso-electric focusing (IEF). 15 Two methods of analysis must be applied to all screen positive results. The conditions screened for are:- Sickle cell anaemia (Hb SS), Hb SC disease, Hb S/β-thalassaemia, Hb S/DPunjab, Hb S/OArab, Hb S/HPFH. Carriers identified for the common haemoglobin variants are reported to parents and follow-up counselling is offered. A bespoke laboratory quality assurance programme has been established which has defined standards of satifactory performance. Results Provisional figures from the first seven months of screening (up to March 2004) 108,255 infants were screened gave a screen positive rate of 1:900 for these high prevalence areas and a carrier rate of 2.7%. Figures for 2004-2005 show about 250 significant screen positive results for sickle cell disorders and about 6,500 carriers were identified. The birth prevalence for screen positive results from 2004-05 is 1:1500. We estimate that when there is countrywide data, the national birth prevalence will be about 1:2000-1:2,500. Conclusion The results from the national newborn sickle cell screening programme in England - show that the sickle cell disorders are as common as cystic fibrosis (CF) in England, although the distribution of cases is concentrated in London and other urban areas. The findings and approach to implementation adopted in England may be of interest to other Western European countries with increasing rates of sickle cell disease who are considering such programmes and also to other developed countries.

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Ciller, U. A., J. D. McFarlane e J. R. McFarlane. "512. COMMERCIAL EQUINE CHORIONIC GONADOTROPHIN ISOFORM COMPOSITION, IMMUNOACTIVITY, AND BIOACTIVITY IN A MURINE MODEL USING OVARIAN AUGMENTATION AND TESTICULAR INTERSTITIAL CELL BIOASSAYS". Reproduction, Fertility and Development 21, n. 9 (2009): 111. http://dx.doi.org/10.1071/srb09abs512.

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Equine chorionic gonadotrophin (eCG) is a placental glycoprotein hormone that is harvested from the plasma of pregnant mares for the formulation of commercial products which are used in a variety of assisted reproductive procedures in livestock. It is well documented that the bioactivity of gonadotrophin products is highly variable. The aim of this study was therefore to determine how different eCG products affected target tissues and cells. Isoforms of eCG were separated with iso-electric focusing and immunoactivity measured with RIA. For in vivo bioassay, dose-response eCG treatments were administered subcutaneously to immature female mice with follow-up treatment on day 2. On day 3 the mice were asphyxiated and ovaries dissected and weighed relative to standard. For in vitro bioassay, adult male mice were asphyxiated, testes removed, decapsulated, dispersed, strained and washed with DMEM:F12 0.1% BSA. The cell stock was counted and diluted for culture at 20,000 cells/well. Cell viability was determined using trypan blue. Five doses were tested for each eCG product. The cells were incubated at 32ºC for 3 hours in 5.0% CO2 in humidified conditions. Media was collected after 3 hours and immediately assayed for testosterone with RIA. Product eCG with ~90% isoforms with pH 3.0–3.7 and ~10% with pH 3.8–4.4, showed 29% greater biologically activity in the ovarian augmentation assay and 44.8% more immunoactivity then stated product bioactivity. Product eCG with ~70% isoforms with pH 3.0–3.7 and ~30% with pH 3.8–7.4 was 3.0% less effective in vivo and had 7.9% less immunoactivity then stated bioactivity, however, in vitro testosterone production was more effectively stimulated then with the previous more acidic eCG product. Our study shows a selective difference in commercial eCG biological activity that appears to depend on subtle isoform heterogeneity. Future studies aim to determine the specific actions of eCG isoforms in target tissues.

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Wepner, Lena, Harald Andreas Färber, Andreas Jaensch, Anna Weber, Florian Heuser, Ludger Keilig, Lamia Singer e Christoph Peter Bourauel. "In Vitro Ion Release of Wires in Removable Orthodontic Appliances". Materials 14, n. 12 (19 giugno 2021): 3402. http://dx.doi.org/10.3390/ma14123402.

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Various orthodontic wire compositions and configurations are present on the market for removable appliances; however, there have still been only few studies focusing on the effect of resin color and additives such as glitter on corrosion of metallic wires under different conditions. Thus, the aim of the study was to compare concentrations of released ions (aluminium, chromium, nickel) in a corrosive medium under three different conditions: non-loaded wires, loaded wires, and non-loaded wires treated with Kukis® cleaning tablets. Six different wires made of three types of steel alloy were embedded in PMMA resin leaving one centimetre of each wire emerging from the resin to come into contact with the corrosive medium. Glitter particles were added to half of the produced test specimens. For the unloaded test series, five specimens of each group were covered in a petri dish with 50 mL of corrosive medium (pH 2.3) following EN-ISO 10271 for seven days at 37 °C. The wires for the mechanically loaded test specimens overlapped the resin by 5 cm and were clamped into a time-switched electric drive for a defined period of time before the samples were taken after a testing time of 7 days. In the third group, unloaded test specimens were transferred from their petri dishes into the prepared Kukis® solution every 24 h before being stored in the corrosive medium. Inductively coupled plasma mass spectrometry (ICP-MS) was used to quantify the specific ions in the corrosive solution. Statistical analysis showed that the mechanical loading of all wires could significantly raise the diffusion of ions into the corrosive medium. The colour of the resin did not affect the concentration of the released ions. The Kukis® cleaning tabs could not lower the corrosion of the tested metals, as some of the wires were corroded even more using the brace cleanser. Glitter-containing test specimens showed significantly higher amounts of aluminium. Mechanical loading as well as the presence of glitter particles in the resin significantly affected ion concentrations.

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Forrest, Richard D., Caroline A. Jackson, Barry J. Gould, Marianne Casburn-Budd, Julie E. Taylor e John S. Yudkin. "Short-Term Effect of a 75 g Oral Glucose Load on Glycohaemoglobin Levels". Annals of Clinical Biochemistry: International Journal of Laboratory Medicine 24, n. 1 (gennaio 1987): 53–57. http://dx.doi.org/10.1177/000456328702400108.

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Two hundred and twenty-three subjects out of a total of 347 with various degrees of glucose tolerance were recalled after a screening survey for diabetes. They were a randomly selected sample of people over the age of 40 and they underwent a formal 75 g glucose tolerance test in order to assess the effect of a glucose load on glycohaemoglobin levels measured by four different assay methods. Oral glucose loading was found to affect glycohaemoglobin levels only when these were measured by an agar-gel electrophoretic method that did not remove the labile aldimine-linked Schiff base fraction. The increase in glycohaemoglobin during the glucose tolerance test as estimated by this method was proportional to the 2 h blood glucose level. Glycohaemoglobin levels measured by agar-gel electrophoresis with elimination of the Schiff base, by affinity chromatography and by iso-electric focussing, were not affected by a 75 g oral glucose load. We conclude that blood samples for glycohaemoglobin assay may be collected at any time of the day, without regard to the subject's previous food intake, provided an assay method is used that removed the aldimine-linked labile fraction.

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Chunda-Liyoka, Catherine Mupela, Ashok A. Kumar, Pauline M. Sambo, Felicity Lubinda, Tyler Humpton, Pauline Okuku, Chimuka Miyanda et al. "Successful Field Test of a Combined Health Access Strategy and Novel Device to Screen for Sickle Cell Disease (SCD) in Rural Sub-Saharan Africa". Blood 132, Supplement 1 (29 novembre 2018): 316. http://dx.doi.org/10.1182/blood-2018-99-114625.

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Abstract Despite the fact that simple interventions and emerging therapies can increase survival of SCD patients, under detection renders SCD a major cause of under age-5 mortality in rural regions of the developing world where it is prevalent. (Piel et PLoS Med DOI: org/10.1371/journal.pmed.1001484, 2013). Two major diagnostic challenges are: 1. A lack of affordable diagnostic methodology to obtain point-of-care results in low-resource environments. 2. Dispersion of SCD patients in vast rural hinterlands who rarely interface with healthcare services. To address the first impediment, we have developed and validated a simple, low-cost test to screen for SCD using aqueous multiphase systems (AMPS). AMPS are solutions of polymers and surfactants that form immiscible self-assembling step-gradients. An AMPS designed to target the density signature of sickle cell anemia forms the basis of this novel diagnostic technique. (Kumar et al, PNAS DOI:10.1073/pnas.14147391110, 2014). Building on a design previously tested in Zambia (Kumar et al, PLoS One DOI: 10.1371/journal.pone.0114540, 2014) an improved test has been developed and named "Mpana" for "Multi-Phase Analyzer." The Mpana test detects the presence or absence of cells with a high mass-density as an indirect method to test for the presence of sickled cells. The test uses 5 µL of fingerstick blood, can be performed in 15 minutes using an inexpensive ($150), battery-powered centrifuge, the results can be read with the naked eyes by a trained reader (Figure 1) and costs 50 cents per test. The improved density-based test was first verified on fingerstick samples in the U.S. before being validated in a field study in rural Zambia. To manage the access difficulty of large-scale rural SCD screening, we exploited a partnership with the National Zambian Dental Training School. We have previously demonstrated that provision of free toothbrushes, toothpaste and other minimal health services is a powerful magnet to attract subjects in rural regions of Zambia that have high rates of tooth decay. Once collected these individuals can receive other healthcare interventions such as SCD screening. We conducted a cross-sectional field test of this approach in August and September of 2017 in the rural Serenje and Chitambo Districts of Northern Zambia. A local drama group and radio and mobile broadcasts informed the target communities about the dental intervention that attracted over 700 subjects. Of these, 503 children aged 1 month to 18 years were symptom screened for SCD, tested with MPANA, and dried blood spot (DBS) samples collected. The DBS were analyzed by iso-electric focusing and high-performance liquid chromatography at the New England Newborn Screening Program. Of the screened subjects, 78 had sickle cell trait and 17 had SCD. A score was assigned to visual readings of the MPANA test to enable ROC analysis.The ROC curve shows good diagnostic performance with an area under the curve (AUC) of 0.84. (Figure 2) The MPANA test had a sensitivity of 71% (CI 47-88%) and a specificity of 99% (CI 98-100%), with an overall diagnostic accuracy of 98% (CI 97-99%). Importantly, the MPANA test had a negative predictive value of 99% (CI 98-100%). Combining Mpana results with a clinical symptom score yielded a slightly improved specificity of 100% (CI 99.5-100%) and yielded an overall diagnostic accuracy of 99% (CI 98-100%). In conclusion, a multidisciplinary consortium has achieved the first validation of a low-cost simple point of care test to diagnose SCD in a rural area of a developing nation and has demonstrated the ability of dental services to facilitate such screening. Offsetting the theoretical concern that the MPANA test might not detect SCD in neonates and young infants due to their high hemoglobin F content are the advantages that our SCD screening strategy is low cost, primarily utilizes local resources and immediately delivers positive subjects to care interventions (which could be anything in addition to or other than SCD screening). It is therefore amenable to scaling up for widespread application. Acknowledgments: The Provincial and District Offices, Rural Health Centers and communities that granted permissions and participated in this study. Author Contributions: Contributed equally to the work - CMCL,AAK,TPS Conflict-of-interest disclosure: Competing financial interests declared. Correspondence: Catherine Chunda-Liyoka, e-mail: catherinechunda@yahoo.co.uk Disclosures Kumar: Harvard University: Patents & Royalties: I am an inventor on patents for the underlying technology and the patent has been assigned to Harvard.. Humpton:Nano Terra, Inc.: Employment. Whitesides:Harvard University: Patents & Royalties: Harvard holds patents for this work. Stossel:Harvard University: Patents & Royalties: Co-inventor on MPANA patent. No royalties.

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Linssen, Matthijs David, Wouter Tjerk Rudolph Hooghiemstra, Annelies Jorritsma-Smit, Derk Pieter Allersma, Gerard Dijkstra e Wouter Bastiaan Nagengast. "Development and Characterisation of Antibody-Based Optical Imaging Probes for Inflammatory Bowel Disease". Pharmaceuticals 14, n. 9 (13 settembre 2021): 922. http://dx.doi.org/10.3390/ph14090922.

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Monoclonal antibodies are an important addition to the medicinal treatment paradigm for IBD patients. While effective, these agents show a high degree of primary and secondary non-response, and methods to predict response are highly desired. Information on drug distribution at the target level is often lacking. Fluorescent endoscopic imaging using labelled antibody drugs may provide insight regarding drug distribution, target engagement and drug response, but these assessments require stable and functional fluorescently-conjugated probes. Infliximab, vedolizumab, adalimumab and ustekinumab were conjugated to IRDye 800CW, IRDye 680LT and ZW800-1. The resulting 12 tracer candidates were analysed and characterised on SE-HPLC, SDS-PAGE, iso-electric focussing (IEF) and ELISA in order to evaluate their feasibility as candidate clinical tracers for cGMP development. Major differences in the conjugation results could be seen for each conjugated drug. For Infliximab, 2 conjugates (800CW and 680LT) showed formation of aggregates, while conjugates of all drugs with ZW800-1 showed reduced fluorescent brightness, reduced purification yield and formation of fragments. All 6 of these candidates were considered unfeasible. From the remaining 6, ustekinumab-680LT showed reduced binding to IL23, and was therefore considered unfeasible. Out of 12 potential tracer candidates, 5 were considered feasible for further development: vedolizumab-800CW, vedolizumab-680LT, adalimumab-800CW, adalimumab-680LT and ustekinumab-800CW. Infliximab-680LT and ustekinumab-680LT failed to meet the standards for this panel, but may be rendered feasible if tracer production methods were further optimized.

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Articoli di riviste sul tema "Iso-electric focusing"

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