734 research outputs found

    AN ALTERNATIVE DIAGNOSTIC DESIGN FOR CHRONIC KIDNEY DISEASE DETECTION BASED ON CYSTATIN C

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    Objective: Chronic Kidney Disease (CKD) is usually diagnosed by measuring the glomerular filtration rate (GFR) and diagnostics are still inadequate at the clinical level. Most of the diagnostic kits available estimate GFR rate by determining clearance of serum creatinine using various instrumentation generally available at hospitals. Serum creatinine is considered the major marker for renal deficiency disorders. Additionally, it is also an indicator of muscle mass and dietary intake. Hence, the need for a more reliable marker for CKD arises. A low molecular weight protein cystatin C has been found to be a reliable biomarker for detection of kidney function as it is solely filtered by the glomerulus and not secreted by renal tubules.Method: The basic set up of the kit was designed using a syringe containing multi walled carbon nanotube (MWCNT) conjugated protease. Casein beads were immersed in  PBS buffer in the syringe. The Glass/MWCNT/papain solid support was subsequently inserted into the syringe in such a way, that the beads came in contact with the immobilized enzyme conjugate. The inhibitory action of cystatin C against protease forms the basis for the functioning of the kitResults: Results indicated that papain while immobilization needs to be in dynamic conformation. At 37 C gave better activity as compared to protein immobilized at 4C. FTIR observations confirmed the physical adsorption on the MWCNTs. The experimentation confirmed the feasibility of using prototype for detection of cystatin C.Discussion: Papain conjugated with MWCNT indicated its temperature and pH stability. The initial design of the diagnostic kit for the detection of CKD has shown to be successful with a good detection range corresponding to stage I and II of CKD. Further testing needs to be done for the prototype using patient samples.Keywords: Chronic kidney disease, Diagnostic kit, Immobilized papain, Protease inhibitor.Â

    A description of the origins, design and performance of the TRAITS-SGP Atlantic salmon Salmo salar L. cDNA microarray

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    The origins, design, fabrication and performance of an Atlantic salmon microarray are described. The microarray comprises 16 950 Atlantic salmon-derived cDNA features, printed in duplicate and mostly sourced from pre-existing expressed sequence tag (EST) collections [SALGENE and salmon genome project (SGP)] but also supplemented with cDNAs from suppression subtractive hybridization libraries and candidate genes involved in immune response, protein catabolism, lipid metabolism and the parr–smolt transformation. A preliminary analysis of a dietary lipid experiment identified a number of genes known to be involved in lipid metabolism. Significant fold change differences (as low as 1.2x) were apparent from the microarray analysis and were confirmed by quantitative real-time polymerase chain reaction analysis. The study also highlighted the potential for obtaining artefactual expression patterns as a result of cross-hybridization of similar transcripts. Examination of the robustness and sensitivity of the experimental design employed demonstrated the greater importance of biological replication over technical (dye flip) replication for identification of a limited number of key genes in the studied system. The TRAITS (TRanscriptome Analysis of Important Traits of Salmon)–salmon genome project microarray has been proven, in a number of studies, to be a powerful tool for the study of key traits of Atlantic salmon biology. It is now available for use by researchers in the wider scientific community

    Cloning and expression of cultural filtrate proteins from novel and native strains of Mycobacterium avium subspecies paratuberculosis and their application in ELISA based sero-diagnosis of Johne's disease

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    219-229Johne's disease (JD), caused by Mycobacterium avium subspecies paratuberculosis (MAP), is endemic in livestock leading to low per animal productivity. MAP as survives pasteurization, poses a public health problem because of high exposure to animals and humans. There is an urgent need for newer diagnostic tests with high specificity and sensitivity as the current ones suffer from lower sensitivity and specificity. In present study, six Mycobacterium avium subspecies paratuberculosis (MAP)-specific culture filtrate proteins (CFPs) were produced and evaluated for sero-diagnosis of MAP infection in goat and cattle herds in India. Genes encoding for six MAP-CFPs were amplified and cloned into easy cloning vector pJET1.2/pTZ57R followed by sub-cloning into expression vector pET28a (+)/pET22b (+) containing C-terminal Histidine. Recombinant CFPs (r-CFPs) expressions were optimized in Escherichia coli (Rosetta cells) and purified using Ni-NTA affinity chromatography. In SDS-PAGE, MAP CFPs viz., 1693c, 2168c, ModD, 85C, Pep AN and Pep AC showed 22, 24, 55, 38, 20 and 25 kDa molecular masses, respectively. Identity of these r-CFPs was further confirmed by immuno-blotting. We developed six different ELISAs using the six individual r-CFPs and one additional ELISA i.e. cocktail ELISA (c-ELISA) was prepared using cocktail of all 6 r-CFPs. The performance of all seven ELISAs were further evaluated against whole cell protoplasmic based indigenous ELISA (i-ELISA). c-ELISA showed almost similar sensitivity as shown by i-ELISA. However, individual r-CFP based ELISA could not reach up to the sensitivity of cocktail of six r-CFPs. None of the r-CFP showed any false positive (as compare to i-ELISA) thereby specificity was 100%. Results of ELISA tests based on cocktail of r-CFPs, ModD and 85C were quite similar to i-ELISA from goat sera whereas in cattle serum c-ELISA was comparable with i-ELISA. Our study showed a comparable specificity of c-ELISA for the diagnosis of JD and it may have applicability in region where disease is endemic. Future validation of c-ELISA against gold standard or confirmatory tests would give a better insight on its diagnostic potential over i-ELISA

    Cloning and expression of cultural filtrate proteins from novel and native strains of Mycobacterium avium subspecies paratuberculosis and their application in ELISA based sero-diagnosis of Johne's disease

    Get PDF
    Johne's disease (JD), caused by Mycobacterium avium subspecies paratuberculosis (MAP), is endemic in livestock leading to low per animal productivity. MAP as survives pasteurization, poses a public health problem because of high exposure to animals and humans. There is an urgent need for newer diagnostic tests with high specificity and sensitivity as the current ones suffer from lower sensitivity and specificity. In present study, six Mycobacterium avium subspecies paratuberculosis (MAP)-specific culture filtrate proteins (CFPs) were produced and evaluated for sero-diagnosis of MAP infection in goat and cattle herds in India. Genes encoding for six MAP-CFPs were amplified and cloned into easy cloning vector pJET1.2/pTZ57R followed by sub-cloning into expression vector pET28a (+)/pET22b (+) containing C-terminal Histidine. Recombinant CFPs (r-CFPs) expressions were optimized in Escherichia coli (Rosetta cells) and purified using Ni-NTA affinity chromatography. In SDS-PAGE, MAP CFPs viz., 1693c, 2168c, ModD, 85C, Pep AN and Pep AC showed 22, 24, 55, 38, 20 and 25 kDa molecular masses, respectively. Identity of these r-CFPs was further confirmed by immuno-blotting. We developed six different ELISAs using the six individual r-CFPs and one additional ELISA i.e. cocktail ELISA (c-ELISA) was prepared using cocktail of all 6 r-CFPs. The performance of all seven ELISAs were further evaluated against whole cell protoplasmic based indigenous ELISA (i-ELISA). c-ELISA showed almost similar sensitivity as shown by i-ELISA. However, individual r-CFP based ELISA could not reach up to the sensitivity of cocktail of six r-CFPs. None of the r-CFP showed any false positive (as compare to i-ELISA) thereby specificity was 100%. Results of ELISA tests based on cocktail of r-CFPs, ModD and 85C were quite similar to i-ELISA from goat sera whereas in cattle serum c-ELISA was comparable with i-ELISA. Our study showed a comparable specificity of c-ELISA for the diagnosis of JD and it may have applicability in region where disease is endemic. Future validation of c-ELISA against gold standard or confirmatory tests would give a better insight on its diagnostic potential over i-ELISA

    Molecular medicine and concepts of disease: the ethical value of a conceptual analysis of emerging biomedical technologies

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    Although it is now generally acknowledged that new biomedical technologies often produce new definitions and sometimes even new concepts of disease, this observation is rarely used in research that anticipates potential ethical issues in emerging technologies. This article argues that it is useful to start with an analysis of implied concepts of disease when anticipating ethical issues of biomedical technologies. It shows, moreover, that it is possible to do so at an early stage, i.e. when a technology is only just emerging. The specific case analysed here is that of ‘molecular medicine’. This group of emerging technologies combines a ‘cascade model’ of disease processes with a ‘personal pattern’ model of bodily functioning. Whereas the ethical implications of the first are partly familiar from earlier—albeit controversial—forms of preventive and predictive medicine, those of the second are quite novel and potentially far-reaching

    Transit timings variations in the three-planet system: TOI-270

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    We present ground- and space-based photometric observations of TOI-270 (L231-32), a system of three transiting planets consisting of one super-Earth and two sub-Neptunes discovered by TESS around a bright (K-mag = 8.25) M3V dwarf. The planets orbit near low-order mean-motion resonances (5:3 and 2:1) and are thus expected to exhibit large transit timing variations (TTVs). Following an extensive observing campaign using eight different observatories between 2018 and 2020, we now report a clear detection of TTVs for planets c and d, with amplitudes of ∼10 min and a super-period of ∼3 yr, as well as significantly refined estimates of the radii and mean orbital periods of all three planets. Dynamical modelling of the TTVs alone puts strong constraints on the mass ratio of planets c and d and on their eccentricities. When incorporating recently published constraints from radial velocity observations, we obtain masses of Mb=1.48± 0.18, M⊕, Mc=6.20± 0.31, M⊕, and Md=4.20± 0.16, M⊕ for planets b, c, and d, respectively. We also detect small but significant eccentricities for all three planets: eb = 0.0167 ± 0.0084, ec = 0.0044 ± 0.0006, and ed = 0.0066 ± 0.0020. Our findings imply an Earth-like rocky composition for the inner planet, and Earth-like cores with an additional He/H2O atmosphere for the outer two. TOI-270 is now one of the best constrained systems of small transiting planets, and it remains an excellent target for atmospheric characterization

    SCORE2-Diabetes: 10-year cardiovascular risk estimation in type 2 diabetes in Europe

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    Aims: To develop and validate a recalibrated prediction model (SCORE2-Diabetes) to estimate the 10-year risk of cardiovascular disease (CVD) in individuals with type 2 diabetes in Europe. Methods and results: SCORE2-Diabetes was developed by extending SCORE2 algorithms using individual-participant data from four large-scale datasets comprising 229 460 participants (43 706 CVD events) with type 2 diabetes and without previous CVD. Sex-specific competing risk-adjusted models were used including conventional risk factors (i.e. age, smoking, systolic blood pressure, total, and HDL-cholesterol), as well as diabetes-related variables (i.e. age at diabetes diagnosis, glycated haemoglobin [HbA1c] and creatinine-based estimated glomerular filtration rate [eGFR]). Models were recalibrated to CVD incidence in four European risk regions. External validation included 217 036 further individuals (38 602 CVD events), and showed good discrimination, and improvement over SCORE2 (C-index change from 0.009 to 0.031). Regional calibration was satisfactory. SCORE2-Diabetes risk predictions varied several-fold, depending on individuals' levels of diabetes-related factors. For example, in the moderate-risk region, the estimated 10-year CVD risk was 11% for a 60-year-old man, non-smoker, with type 2 diabetes, average conventional risk factors, HbA1c of 50 mmol/mol, eGFR of 90 mL/min/1.73 m2, and age at diabetes diagnosis of 60 years. By contrast, the estimated risk was 17% in a similar man, with HbA1c of 70 mmol/mol, eGFR of 60 mL/min/1.73 m2, and age at diabetes diagnosis of 50 years. For a woman with the same characteristics, the risk was 8% and 13%, respectively. Conclusion: SCORE2-Diabetes, a new algorithm developed, calibrated, and validated to predict 10-year risk of CVD in individuals with type 2 diabetes, enhances identification of individuals at higher risk of developing CVD across Europe

    A rockslide-generated tsunami in a Greenland fjord rang Earth for 9 days

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    Climate change is increasingly predisposing polar regions to large landslides. Tsunamigenic landslides have occurred recently in Greenland (Kalaallit Nunaat), but none have been reported from the eastern fjords. In September 2023, we detected the start of a 9-day-long, global 10.88-millihertz (92-second) monochromatic very-long-period (VLP) seismic signal, originating from East Greenland. In this study, we demonstrate how this event started with a glacial thinning–induced rock-ice avalanche of 25 × 106 cubic meters plunging into Dickson Fjord, triggering a 200-meter-high tsunami. Simulations show that the tsunami stabilized into a 7-meter-high long-duration seiche with a frequency (11.45 millihertz) and slow amplitude decay that were nearly identical to the seismic signal. An oscillating, fjord-transverse single force with a maximum amplitude of 5 × 1011 newtons reproduced the seismic amplitudes and their radiation pattern relative to the fjord, demonstrating how a seiche directly caused the 9-day-long seismic signal. Our findings highlight how climate change is causing cascading, hazardous feedbacks between the cryosphere, hydrosphere, and lithosphere.acceptedVersio

    Development of Risk Prediction Equations for Incident Chronic Kidney Disease

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    IMPORTANCE ‐ Early identification of individuals at elevated risk of developing chronic kidney disease  could improve clinical care through enhanced surveillance and better management of underlying health  conditions.  OBJECTIVE – To develop assessment tools to identify individuals at increased risk of chronic kidney  disease, defined by reduced estimated glomerular filtration rate (eGFR).  DESIGN, SETTING, AND PARTICIPANTS – Individual level data analysis of 34 multinational cohorts from  the CKD Prognosis Consortium including 5,222,711 individuals from 28 countries. Data were collected  from April, 1970 through January, 2017. A two‐stage analysis was performed, with each study first  analyzed individually and summarized overall using a weighted average. Since clinical variables were  often differentially available by diabetes status, models were developed separately within participants  with diabetes and without diabetes. Discrimination and calibration were also tested in 9 external  cohorts (N=2,253,540). EXPOSURE Demographic and clinical factors.  MAIN OUTCOMES AND MEASURES – Incident eGFR <60 ml/min/1.73 m2.  RESULTS – In 4,441,084 participants without diabetes (mean age, 54 years, 38% female), there were  660,856 incident cases of reduced eGFR during a mean follow‐up of 4.2 years. In 781,627 participants  with diabetes (mean age, 62 years, 13% female), there were 313,646 incident cases during a mean follow‐up of 3.9 years. Equations for the 5‐year risk of reduced eGFR included age, sex, ethnicity, eGFR, history of cardiovascular disease, ever smoker, hypertension, BMI, and albuminuria. For participants  with diabetes, the models also included diabetes medications, hemoglobin A1c, and the interaction  between the two. The risk equations had a median C statistic for the 5‐year predicted probability of  0.845 (25th – 75th percentile, 0.789‐0.890) in the cohorts without diabetes and 0.801 (25th – 75th percentile, 0.750‐0.819) in the cohorts with diabetes. Calibration analysis showed that 9 out of 13 (69%) study populations had a slope of observed to predicted risk between 0.80 and 1.25. Discrimination was  similar in 18 study populations in 9 external validation cohorts; calibration showed that 16 out of 18 (89%) had a slope of observed to predicted risk between 0.80 and 1.25. CONCLUSIONS AND RELEVANCE – Equations for predicting risk of incident chronic kidney disease developed in over 5 million people from 34 multinational cohorts demonstrated high discrimination and  variable calibration in diverse populations
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