The Isoelectric Region of Proteins: A Systematic Analysis

Background: Binding of proteins in ion exchange chromatography is dominated by electrostatic interactions and can be tuned by adjusting pH and ionic strength of the solvent. Therefore, the isoelectric region (IER), the pH region of almost zero charge near the pI, has been used to predict the binding properties of proteins. Principal findings: Usually the IER is small and binding and elution is carried out at pH values near to the pI. However, some proteins with an extended IER have been shown to bind and elute far away from its pI. To analyze factors that mediate the size of the IER and to identify proteins with an extended IER, two protein families consisting of more than 7000 proteins were systematically investigated. Most proteins were found to have a small IER and thus are expected to bind or elute near to their pI, while only a small fraction of less than 2 % had a large IER. Conclusions: Only four factors, the number of histidines, the pI, the number of titratable amino acids and the ratio of acidic to basic residues, are sufficient to reliably classify proteins by their IER based on their sequence only, and thus to predict their binding and elution behaviour in ion exchange chromatography

Enhanced serum concentrations of transforming growth factor-beta1 in simple fatty liver: is it really benign?

<p>Abstract</p> <p>Background</p> <p>Inside the spectrum of non-alcoholic fatty liver disease, simple fatty liver is generally thought of as being "non progressive", differently from non-alcoholic steatohepatitis, which increases in severity due to the presence of apoptosis/inflammation and fibrosis. The "benignity" of fatty liver is widely accepted but conceptually difficult to maintain because the mechanisms underlying this entity are the same ones that determine the more severe form.</p> <p>Findings provide evidence that iron overload is associated with increased liver damage and collagen deposition. Transforming growth factor-beta1 released by hepatic stellate cells during chronic liver injury plays a critical role in liver apoptosis and fibrogenesis.</p> <p>Objective</p> <p>To verify whether both the forms of non-alcoholic fatty liver disease were really dissimilar, evaluating the serum profile of two key parameters, indexes of severity.</p> <p>Methods</p> <p>A total of 123 patients (57 females) participated, forming three groups: forty five patients with fatty liver, 42 patients with non-alcoholic steatohepatitis and 36 with chronic hepatitis C. All had a biopsy-proven diagnosis.</p> <p>Measurements</p> <p>Serum concentrations of transforming growth factor-beta1 and ferritin.</p> <p>Results</p> <p>High concentrations of transforming growth factor-beta1 were noticed in patients suffering from both fatty liver and non-alcoholic steatohepatitis, 129.1 (45.4) versus 116.8 (42.2) ng/mL, P = 0.2; they were significantly superior to those of chronic hepatitis C patients 87.5 (39.5) ng/mL, P < 0.001. Ferritin levels were on average above normal values and similar in the three groups (P = 0.9), also when adjusted for gender (P = 0.5) and age (P = 0.3).</p> <p>Conclusion</p> <p>No difference between serum concentrations of transforming growth factor-beta1 and ferritin in fatty liver and non-alcoholic steatohepatitis suggests that these forms share more common aspects, regarding their progression, than previously thought.</p

Biological effects of naturally occurring and man-made fibres: in vitro cytotoxicity and mutagenesis in mammalian cells

Cytotoxicity and mutagenicity of tremolite, erionite and the man-made ceramic (RCF-1) fibre were studied using the human– hamster hybrid A L cells. Results from these fibres were compared with those of UICC Rhodesian chrysotile fibres. The A L cell mutation assay, based on the S1 gene marker located on human chromosome 11, the only human chromosome contained in the hybrid cell, has been shown to be more sensitive than conventional assays in detecting deletion mutations. Tremolite, erionite and RCF-1 fibres were significantly less cytotoxic to A L cells than chrysotile. Mutagenesis studies at the HPRT locus revealed no significant mutant yield with any of these fibres. In contrast, both erionite and tremolite induced dose-dependent S1− mutations in fibre-exposed cells, with the former inducing a significantly higher mutant yield than the latter fibre type. On the other hand, RCF-1 fibres were largely non-mutagenic. At equitoxic doses (cell survival at ∼ 0.7), erionite was found to be the most potent mutagen among the three fibres tested and at a level comparable to that of chrysotile fibres. These results indicate that RCF-1 fibres are non-genotoxic under the conditions used in the studies and suggest that the high mesothelioma incidence previously observed in hamster may either be a result of selective sensitivity of hamster pleura to fibre-induced chronic irritation or as a result of prolonged fibre treatment. Furthermore, the relatively high mutagenic potential for erionite is consistent with its documented carcinogenicity. © 1999 Cancer Research Campaig

Results from the WHO external quality assessment for the respiratory syncytial virus pilot, 2016-17

Background: External quality assessments (EQAs) for the molecular detection of respiratory syncytial virus (RSV) are necessary to ensure the provision of reliable and accurate results. One of the objectives of the pilot of the World Health Organization (WHO) Global RSV Surveillance, 2016-2017, was to evaluate and standardize RSV molecular tests used by participating countries. This paper describes the first WHO RSV EQA for the molecular detection of RSV. Methods: The WHO implemented the pilot of Global RSV Surveillance based on the WHO Global Influenza Surveillance and Response System (GISRS) from 2016 to 2018 in 14 countries. To ensure standardization of tests, 13 participating laboratories were required to complete a 12 panel RSV EQA prepared and distributed by the Centers for Disease Control and Prevention (CDC), USA. The 14th laboratory joined the pilot late and participated in a separate EQA. Laboratories evaluated a RSV rRT-PCR assay developed by CDC and compared where applicable, other Laboratory Developed Tests (LDTs) or commercial assays already in use at their laboratories. Results: Laboratories performed well using the CDC RSV rRT-PCR in comparison with LDTs and commercial assays. Using the CDC assay, 11 of 13 laboratories reported correct results. Two laboratories each reported one false-positive finding. Of the laboratories using LDTs or commercial assays, results as assessed by Ct values were 100% correct for 1/5 (20%). With corrective actions, all laboratories achieved satisfactory outputs. Conclusions: These findings indicate that reliable results can be expected from this pilot. Continued participation in EQAs for the molecular detection of RSV is recommended. </div

Results from the WHO external quality assessment for the respiratory syncytial virus pilot, 2016-17

BACKGROUND : External quality assessments (EQAs) for the molecular detection of respiratory syncytial virus (RSV) are necessary to ensure the provision of reliable and accurate results. One of the objectives of the pilot of the World Health Organization (WHO) Global RSV Surveillance, 2016-2017, was to evaluate and standardize RSV molecular tests used by participating countries. This paper describes the first WHO RSV EQA for the molecular detection of RSV. METHODS : The WHO implemented the pilot of Global RSV Surveillance based on the WHO Global Influenza Surveillance and Response System (GISRS) from 2016 to 2018 in 14 countries. To ensure standardization of tests, 13 participating laboratories were required to complete a 12 panel RSV EQA prepared and distributed by the Centers for Disease Control and Prevention (CDC), USA. The 14th laboratory joined the pilot late and participated in a separate EQA. Laboratories evaluated a RSV rRT-PCR assay developed by CDC and compared where applicable, other Laboratory Developed Tests (LDTs) or commercial assays already in use at their laboratories. RESULTS : Laboratories performed well using the CDC RSV rRT-PCR in comparison with LDTs and commercial assays. Using the CDC assay, 11 of 13 laboratories reported correct results. Two laboratories each reported one false-positive finding. Of the laboratories using LDTs or commercial assays, results as assessed by Ct values were 100% correct for 1/5 (20%). With corrective actions, all laboratories achieved satisfactory outputs. CONCLUSIONS : These findings indicate that reliable results can be expected from this pilot. Continued participation in EQAs for the molecular detection of RSV is recommended.The Bill and Melinda Gates Foundation, the Respiratory Viruses Branch, Division of Viral Diseases, CDC, Atlanta, and the CDC International Reagent Resource (IRR), USA.http://www.wileyonlinelibrary.com/journal/irvam2020Medical Virolog

A comparative study of anthropometric parameters and their relation to arterial blood pressure and fasting blood glucose in type -2 diabetes mellitus patients and non-diabetic controls

Background: Patients of Diabetic Mellitus (DM) are more prone for cardiovascular disease. Concomitant chronic diabetes mellitus and cardiovascular disease can have devastating consequences which can worsen the future outcomes of these diseases related to mortality and morbidity. Hence constant follow up of the patient with effective prognostic indicators is very important in modulating the disease outcome either by medical or surgical intervention. At the same time it is even more important in identifying appropriate indicators for assessing the status of the patient. Even though few available indicators are useful in accurately predicting the disease status of the patients, considering the socioeconomic status of countries like India it is desirable to find alternative approaches having qualities of affordability, adoptability, accessibility and applicability. Objectives: To assess Body mass index (BMI), Waist circumference (WC), Arterial Blood pressure (BP) and Fasting blood glucose (FBS) in persons of 40-60 years having Type 2 diabetes mellitus and in age and sex matched healthy persons.To compare the parameter in the above two groups and also to find correlation between anthropometric parameters like BMI and WC with FBS and BP. Materials and methods: Anthropometric measures (BMI, WC) ,Fasting blood sugar (FBS) and blood pressure (BP) were measured ,compared and their correlation was studied in male patients with type 2DM (Group 2) and normal healthy male subjects (Group1) of age group 40-60 years. Results on continuous measurements are presented on Mean ± SD and significance was assessed at 5 % level of significance. Student t test (two tailed, independent) has been used to find the significance of study parameters. Pearson correlation has been used to find the correlation of BMI and WC with FBS and BP. Result: In the present study, there was significant increase in DBP in diabetics and not much difference in SBP when compared to healthy individuals. Also, it is observed that BMI is positively correlated with FBS, and SBP. It is also observed that WC is strongly positive correlated with SBP and DBP and a weakly positive correlated with FBS. Conclusion: From the findings of the present study it is concluded that both BMI and WC had a positive correlation with FBS and BP.Thus simple anthropometric measures like BMI and WC can independently contribute to the prediction of risk factors of CVD and can be routinely used to identify those at risk

A study of gender difference in time perception in urban population of southern India

Background: It is well known fact that individual perception time is different from normal physical time. Time perception is a field of study within psychology and neuroscience that refers to the subjective experience of time. With the advancing age perception of time varies significantly. There are very few studies were done regarding gender differences in time perception. Aims and Objectives: To calculate the time perception in male and female population separately and compare the two groups to find any significant difference in time perception. Materials and Methods: 50 healthy males (Group A) and 50 healthy female individuals (Group B) within the age group of 20 to 25 years from the surrounding areas of Hyderabad were recruited for study. Individuals were asked to separate and count red colored beads from the colored mixture of beads which are present in a bowl. The means of perceived times of Group A and Group B are compared using student‘t’ test to find out any significance. Results: Mean value of Group 1 is 33.13 ±7.04 and Group 2 is 40.38± 7.63. After statistical analysis for above test p˂0.05 and it was considered to be statistically significant. Conclusion: From above data, there is statistically significant difference is seen in time perception of female and male individual