Model multiple antigenic and homopolymeric peptides from non-repetitive sequences of malaria merozoite proteins elicit biologically irrelevant antibodies

AbstractThree model peptides containing B-epitopes from conserved, non-repetitive regions of the merozoite surface antigens, MSA2 and MSA1, and the erythrocyte binding protein EBP of Plasmodium falciparum were synthesised. The peptides incorporated GPG spacers and C residues at the N and C termini, and were polymerised by oxidation to form cystine bridges. Multiple copies of essentially the same peptide sequences were also synthesised on a branching lysyl matrix to form a tetrameric multiple antigen peptide. Rabbits were immunised with the polymerised and multiple antigen peptides, in alum followed by Freund’s adjuvant, and the antibody responses examined by IFA and ELISA. Reproducible antibody responses were obtained against the MSA1 and EBP but not MSA2 peptides. IgG antibody levels detected by ELISA after three injections of antigen in alum, increased significantly after further immunisation in Freund’s adjuvant. IgG levels were largely maintained for at least 23 weeks after the final immunisation. IgM antibodies, generally detectable only after immunisation in Freund’s adjuvant, were absent 23 weeks later. Antibody titres against the native protein on fixed parasites, assayed by IFA, were three to five orders of magnitude lower than the corresponding ELISA titres against the peptides. Antibody-dependent inhibition of P. falciparum growth in vitro could not be demonstrated with the immune rabbit sera. The MSA1 and EBP peptides elicited cross-reactive antibodies. The results suggest that the selected non-repetitive sequences are conformationally constrained in the native proteins and only a small proportion of the anti-peptide antibodies bind to the native proteins. The significance of the findings for the development of peptide vaccines and the use of peptides in immunoassays is discussed

Trends in maternal mortality in a tertiary care hospital

Background: To analyze the trends in maternal mortality in a tertiary hospital in Salem, Tamil Nadu.Methods: Design of the study was retrospective. Records of all maternal deaths occurring for the past 3 years from January 2013-December 2015 were studied and various factors analyzed and compared.Results: The maternal mortality rate ranged between 559-802/ 1,00,000 live births in our study. The majority of deaths were in the age group between 21-25 yrs. The majority of deaths in 2013 were due to hemorrhage (19.5%) followed by cortical venous thrombosis (17.6%), hypertensive disorders (14.6%). But in 2014 and 2015 hypertensive disorders were the common cause of death, [2014 (23%), 2015 (26.78%)] followed by hemorrhage (2014-12.8%, 2015 -17.5%) and sepsis (2014-20.5%, 2015-12.5%).Conclusions: Majority of maternal deaths can be prevented by adopting improved standards in early identification of preeclampsia, anemia and its management and early referral. Routine iron and folic acid supplementation to be done in an effective way. Proper antenatal care, emergency obstetrics care and routine audits are very much essential to decrease the maternal mortality as well as to know the trends of maternal deaths to develop subsequent management protocols

Artificial Neural Network Optimization Modeling On Engine Performance Of Diesel Engine Using Biodiesel Fuel

This paper presents a study of engine performance using a mixture of palm oil methyl ester blends with diesel oil as biodiesel in a diesel engine, and optimizes the engine performance using artificial neural network (ANN) modeling. To acquire data for training and testing of the proposed ANN, a four-cylinder, four-stroke diesel engine was fuelled with different palm oil methyl ester blends as biodiesel, operated at different engine loads. The properties of biodiesel produced from waste vegetable oil were measured based on ASTM standards. The experimental results revealed that blends of palm oil methyl ester with diesel fuel provided better engine performance. An ANN model was developed based on the Levenberg-Marquardt algorithm for the engine. Logistic activation was used for mapping between the input and output parameters. It was observed that the ANN model could predict the engine performance quite well with correlation coefficients (R) of 0.996684, 0.999, 0.98964 and 0.998923 for the incylinder pressure, heat release, thermal efficiency, and volume, respectively. The predicted MSE (mean square error) error was between the desired outputs, as the measured and simulated values were obtained as 0.0001 by the model. Long-term effects on engine performance when running on biodiesel fuel can be further studied and improved

The ORNATE India project: Building research capacity and capability to tackle the burden of diabetic retinopathy-related blindness in India

The ORNATE India project is an interdisciplinary, multifaceted United Kingdom (UK)–India collaborative study aimed to build research capacity and capability in India and the UK to tackle the burden of diabetes-related visual impairment. For 51 months (October 2017–December 2021), this project built collaboration between six institutions in the UK and seven in India, including the Government of Kerala. Diabetic retinopathy (DR) screening models were evaluated in the public system in Kerala. An epidemiological study of diabetes and its complications was conducted through 20 centers across India covering 10 states and one union territory. The statistical analysis is not yet complete. In the UK, risk models for diabetes and its complications and artificial intelligence-aided tools are being developed. These were complemented by joint studies on various aspects of diabetes between collaborators in the UK and India. This interdisciplinary team enabled increased capability in several workstreams, resulting in an increased number of publications, development of cost-effective risk models, algorithms for risk-based screening, and policy for state-wide implementation of sustainable DR screening and treatment programs in primary care in Kerala. The increase in research capacity included multiple disciplines from field workers, administrators, project managers, project leads, screeners, graders, optometrists, nurses, general practitioners, and research associates in various disciplines. Cross-fertilization of these disciplines enabled the development of several collaborations external to this project. This collaborative project has made a significant impact on research capacity development in both India and the UK

Polymorphisms in pattern recognition receptor genes of indigenous and White Leghorn breeds of chicken

Functional polymorphisms in pattern recognition receptors (PRRs) modulate innate immunity and play a crucial role in resistance or susceptibility to diseases. The present study was carried out to explore polymorphic patterns in the coding sequences of PRR genes TLR3, TLR1LA (TLRs), MDA5, LGP2 (RLRs) and NOD1 (NLR) in chicken breeds of India, namely Ghagus (GH), Nicobari (NB) and the exotic White Leghorn (WLH) breed. Out of 209 SNPs observed in five genes among three breeds, 117 were synonymous (Syn) and 92 were non-synonymous (NS) SNPs. In TLR genes the highest polymorphism was observed in NB (16, 28) compared to GH (14, 16) and WLH (13, 19) breeds. In the MDA5 gene the highest polymorphism was observed in GH (12) compared to NB (eight) and WLH (four) breeds. However, an almost similar level of polymorphism was observed in the LGP2 gene among the three breeds. In the NOD1 gene, the highest polymorphism was observed in NB (27), followed by WLH (11) and GH (10) breeds. The overall highest number of SNPs was observed in NB (90), followed by GH (62) and the WLH (57) breed. With regard to variation in polymorphism among different classes of PRRs, the study revealed the highest polymorphism in TLRs compared to NOD1 and the RLR class of PRRs. Further, the domain locations of various Syn and NS SNPs in each PRR among the three breeds were identified. In silico analysis of NS SNPs revealed that most of them had a neutral effect on protein function. However, two each in TLR1LA and LGP2 and one in the MDA5 gene were predicted to be deleterious to protein function. The present study unravelled extensive polymorphism in the coding sequences of the TLR and NLR class of PRR genes, and the polymorphism was higher in indigenous chicken breeds.</p

Amorphous carbon film deposition on inner surface of tubes using atmospheric pressure pulsed filamentary plasma source

Uniform amorphous carbon film is deposited on the inner surface of quartz tube having the inner diameter of 6 mm and the outer diameter of 8 mm. A pulsed filamentary plasma source is used for the deposition. Long plasma filaments (~ 140 mm) as a positive discharge are generated inside the tube in argon with methane admixture. FTIR-ATR, XRD, SEM, LSM and XPS analyses give the conclusion that deposited film is amorphous composed of non-hydrogenated sp2 carbon and hydrogenated sp3 carbon. Plasma is characterized using optical emission spectroscopy, voltage-current measurement, microphotography and numerical simulation. On the basis of observed plasma parameters, the kinetics of the film deposition process is discussed

Comparison of two ultra-widefield cameras with high image resolution and wider view for identifying diabetic retinopathy lesions

Purpose: To compare the effectiveness of the Optos P200dTx and Zeiss Clarus 50fundus cameras in detecting diabetic retinopathy (DR) lesions. Methods: A cross-sectional study was conducted among 243 patients with clinically diagnoseddiabetesmellituswhowerereferredforaneyeexaminationfromtwotertiary eye care centers in Chennai, India. Patients underwent DR screening based on mydriatic fundal images acquired by both fundal cameras. Fundal images from the two separate devices for each eye were compared based on accurately identified pathological retinal lesions with respect to type and location. Results: When studying lesions of the central retina, they were better identified by the Zeiss Clarus compared with the Optos P200dTx, with six out of eight being statistically significant (P < 0.05). However, lesions of the mid-peripheral retina and peripheral retina were better identified by the Optos P200dTx than the Zeiss Clarus, with three out of eight lesions and five out of eight lesions being statistically significant (P < 0.05), respectively. Based on the color and size of lesions, the Optos P200dTx had a higher chance (59.6%) of missing white lesions than did the Zeiss Clarus (17%) (P < 0.0001). Consequently, small-and medium-sized lesions were missed more by the Optos P200dTx (30.72% and 32.63%, respectively) than the Zeiss Clarus (22.3% and 19.30%, respectively). Conclusions: The capability of detecting or missing a particular DR lesion among diabetics differed between the two cameras based on effective field of view, resolution, and the retinal zone being imaged. Translational Relevance: The choice of which ultra-widefield camera to be used for screening DR can be based on the greater prevalence of central versus peripheral retinal lesions noted in the patient population seen in a clinical practice

The impact of COVID-19 vaccines on male semen parameters: a retrospective cohort study

The emergence of SARS-CoV-2 and the subsequent COVID-19 pandemic necessitated the development of adequate vaccines. Despite vaccines being demonstrated to be safe and effective for preventing severe disease and death, vaccine hesitancy remains. Reasons include concerns over adverse effects on male fertility, which have not been widely investigated. Therefore, this study is aimed at determining the impact of COVID-19 vaccination on semen parameters in a retrospective cohort study of South African males undergoing fertility assessment. The patients for this study were adult men who have previously undergone routine semen analysis for fertility assessment at Androcryos Andrology Laboratory (Johannesburg, South Africa) between March 2021 and March 2022. They also received vaccination within 3 months following a semen analysis and underwent a second semen analysis any time post-COVID-19 vaccination. From 277 records analysed, 46 patients met the inclusion criteria, receiving the Pfizer-BioNTech (BNT162b1) (63%), Johnson and Johnson (JNJ-78436735/Ad26.COV2S) (34.8%), and the AstraZeneca (AZD1222) (2.2%) vaccines. Sperm concentration significantly increased postvaccination (), with no significant changes in semen pH, volume, total sperm count, progressive motility, normal sperm morphology, or chromatin condensation. Results were not influenced by age, type of vaccine received, and the number of days following vaccination, as depicted by multiple regression analysis. In conclusion, there is no evidence of a negative impact of COVID-19 vaccination on male semen parameters, which is consistent with the emerging literature on COVID-19 vaccination and male fertility. COVID-19 vaccinations should not be dismissed based on fear of adverse effects on male fertility parameters

Simple sequence repeat markers useful for sorghum downy mildew (Peronosclerospora sorghi) and related species

<p>Abstract</p> <p>Background</p> <p>A recent outbreak of sorghum downy mildew in Texas has led to the discovery of both metalaxyl resistance and a new pathotype in the causal organism, <it>Peronosclerospora sorghi</it>. These observations and the difficulty in resolving among phylogenetically related downy mildew pathogens dramatically point out the need for simply scored markers in order to differentiate among isolates and species, and to study the population structure within these obligate oomycetes. Here we present the initial results from the use of a biotin capture method to discover, clone and develop PCR primers that permit the use of simple sequence repeats (microsatellites) to detect differences at the DNA level.</p> <p>Results</p> <p>Among the 55 primers pairs designed from clones from pathotype 3 of <it>P. sorghi</it>, 36 flanked microsatellite loci containing simple repeats, including 28 (55%) with dinucleotide repeats and 6 (11%) with trinucleotide repeats. A total of 22 microsatellites with CA/AC or GT/TG repeats were the most abundant (40%) and GA/AG or CT/TC types contribute 15% in our collection. When used to amplify DNA from 19 isolates from <it>P. sorghi</it>, as well as from 5 related species that cause downy mildew on other hosts, the number of different bands detected for each SSR primer pair using a LI-COR- DNA Analyzer ranged from two to eight. Successful cross-amplification for 12 primer pairs studied in detail using DNA from downy mildews that attack maize (<it>P. maydis & P. philippinensis</it>), sugar cane (<it>P. sacchari</it>), pearl millet (<it>Sclerospora graminicola</it>) and rose (<it>Peronospora sparsa</it>) indicate that the flanking regions are conserved in all these species. A total of 15 SSR amplicons unique to <it>P. philippinensis </it>(one of the potential threats to US maize production) were detected, and these have potential for development of diagnostic tests. A total of 260 alleles were obtained using 54 microsatellites primer combinations, with an average of 4.8 polymorphic markers per SSR across 34 <it>Peronosclerospora, Peronospora and Sclerospora </it>spp isolates studied. Cluster analysis by UPGMA as well as principal coordinate analysis (PCA) grouped the 34 isolates into three distinct groups (all 19 isolates of <it>Peronosclerospora sorghi </it>in cluster I, five isolates of <it>P. maydis </it>and three isolates of <it>P. sacchari </it>in cluster II and five isolates of <it>Sclerospora graminicola </it>in cluster III).</p> <p>Conclusion</p> <p>To our knowledge, this is the first attempt to extensively develop SSR markers from <it>Peronosclerospora </it>genomic DNA. The newly developed SSR markers can be readily used to distinguish isolates within several species of the oomycetes that cause downy mildew diseases. Also, microsatellite fragments likely include retrotransposon regions of DNA and these sequences can serve as useful genetic markers for strain identification, due to their degree of variability and their widespread occurrence among sorghum, maize, sugarcane, pearl millet and rose downy mildew isolates.</p