Evaluation of CD8+ T cell responses towards conserved HIV-1 epitopes in naturally infected and vaccinated individuals

Human Immunodeficiency Virus (HIV) infection is a global public health priority. An effective HIV-1 vaccine strategy must overcome the enormous genetic diversity generated by the virus while inducing potent, long lasting immune responses. In this thesis, virus-specific cellular immune responses directed towards HIV conserved regions were evaluated using a validated IFN-γ enzyme-linked immunospot (ELISpot) assay and two sets of peptide panels based upon HIV-1 vaccine candidates. One panel was based on the 14 of the most highly conserved (HIVconsv – 806 amino acids) regions of the HIV-1 proteome and was designed to provide extensive coverage of subtypes A, B, C and D. The second panel represents Gag, Reverse Transcriptase (RT), Integrase (INT), Nef and Envelope sequences derived from a consensus subtype A reference (GRIN/Env). The purpose of this study was to examine the extent of T cell responses to HIV-1 epitopes elicited at different stages of HIV-1 infection and in vaccinees. Individuals infected with HIV-1 subtypes (A, B, C and D) from the UK, Rwanda, Uganda, and Zambia representing a wide range of genetic backgrounds were tested using a HIVconsv peptide matrix and GRIN pools. CD8 responses were identified across Gag, RT and INT and there was no apparent subtype specific bias in terms of recognition of both peptide panels (HIVconsv and GRIN/Env). GRIN appeared to be more antigenic because GRIN incorporated both conserved and variable epitopes compared to HIVconsv panel that only comprised conserved peptide sequences. Furthermore, there was no association between IFN-γ T cell responses and control of viraemia in early infection between viraemic controllers (VC) and viraemic progressors (VP). However, VC appeared to be slightly more polyfunctional than VP. Viral inhibition assay (VIA) employed to assess the vaccine specific responses demonstrated that conserved regions of the HIV-1 proteome could result in an increased ability to inhibit a panel of HIV-1 isolates in vitro. Although detection of a CD8+ T cell response against a particular epitope does not necessarily translate to protection, the conserved nature of HIV-1 epitopes suggests that these domains are immunogenic and might be important for viral function. Thus, these data support the inclusion of conserved sequences in any future vaccine candidate.Open Acces

Knowledge and skills in community oriented medical education (COME)self-ratings of medical undergraduates in Karachi

Objective: To assess the satisfaction of medical students regarding community oriented knowledge and skills that are proposed to be part of the current undergraduate medical curriculum. Methods: Competencies listed in the regulations for medical education designed by the Pakistan Medical and Dental Council (PMDC) were used to develop a self-administered questionnaire. Using the questionnaire 220 final year students of 3 public sector medical schools self-rated the knowledge and skills that should be part of the curriculum. For analysis the questions were grouped into courses of Basic, Clinical and Community Health Sciences. Students ranked their perceptions on a Likert scale of 0-4 for each question. Descriptive analysis was done to calculate the proportion of satisfied and dissatisfied students using the median of the highest possible score as the cut off. Results: The analysis of knowledge gained found a greater proportion of satisfied students with the Basic (55.9%) and Clinical Sciences (50.9%) courses than the Community Health Sciences course (45.5%). Analysis of skills acquired uniformly showed a low percentage of satisfied students for Basic (39.1%), Clinical (29.7%) and Community Health Sciences (19.1%). The proportion of students dissatisfied with their knowledge and skills for different courses ranged from 38.2-85%. Conclusion: Students perceive that current medical school curricula are unable to meet the required standards. Proper implementation of community oriented curricula is the first step towards effective health care provisio

Cognitive Impairments in Children with Down Syndrome

This study is designed to determine the cognitive impairments in individuals with Down syndrome. This study was conducted in September to November 2014. Sample of 30 patients was taken by using purposive sampling technique within three months. Observational and Cross-sectional study design was used. This was a hospital-based study in which patients with Down’s syndrome between the age range of 5-18 and both genders were included. A structured questionnaire was developed that was based on Piaget’s theory of cognitive development to assess the cognitive abilities by assessing tasks related to developmental ages. Out of those 30 patients 15(50٪) were male and 15(50٪) were females. Most of the patients were found in age range of 5-10 years according to frequency 16 (53.3٪) followed by 10 (33.3٪) patients in 10-15 years and 4 (13.3٪) in 15-20 years. The preoperational stage of cognitive development showed that the girls were more impaired. Pretend-play (boys (50%), girls(46.7%)),Centration(boys(40.%), girls(33.3%) and irreversibility boys (50%) girls(40.%) are the aspects in which boys were tending to show better than boys. In concrete operational stage and in formal operational stage both genders were tending to show equal impairments in their cognitive aspects. In the children with Down syndrome it is observed that there is high frequency of cognitive impairment and girls are more cognitively impaired than boys. While the tasks which require more accuracy and intelligence such as reasoning, meta-cognition, inductive and deductive reasoning are rarely present in both genders. Keywords: Down syndrome, pre-operational, concrete-operational and formal-operational. DOI: 10.7176/JHMN/71-12 Publication date: February 29th 202

Alternate efflux pump mechanism may contribute to drug resistance in extensively drug-resistant isolates of mycobacterium tuberculosis

INTRODUCTION: Extensively drug-resistant tuberculosis (XDR-TB) has emerged as one of the biggest threats to public health and TB control programs worldwide. XDR-TB is caused by Mycobacterium tuberculosis (MTB) strains resistant to rifampin and isoniazid, as well as to a fluoroquinolone and to at least one injectable aminoglycoside. Drug resistance in MTB has primarily been associated with single nucleotide polymorphisms (SNPs) in particular genes. However, it has also been shown that efflux pumps may play a role in resistance of MTB. Upregulation of drug efflux pumps can decrease the intracellular concentration of drugs and reduce their efficacy. METHODS: Whole genome sequencing was performed on 32 XDR-TB clinical isolates. Sequence data were used to investigate SNPs in efflux pump genes as compared with the H37Rv reference genome. RESULTS: Of the XDR MTB strains, eight (21.62%) were wild type for rpsL, rrs (500 region), and gidB genes, but had non-synonymous (ns) SNPs (aspartic acid to histidine) in the drrA efflux pump gene at position 3273138. Three of eight (37.5%) XDR MTB strains, wild type for rpsL, rrs (500 region), gidB, and gyrB genes were phenotypically streptomycin sensitive and five (62.5%) XDR MTB strains were streptomycin resistant, while all XDR MTB strains, wild type for rpsL, rrs, gidB, and gyrB genes were resistant to fluoroquinolone (ofloxacin) and ethambutol. In addition, three XDR MTB strains wild type for rpsL, rrs, gidB, and drrA genes showed nsSNPs (isoleucine to valine) in the major facilitator superfamily, Rv1634 efflux pump gene at position 1839306. CONCLUSION: Our data show an nsSNP in the drrA efflux pump gene that may result in upregulation of drug efflux mechanisms in MTB strains. It is therefore imperative to understand the mechanism of efflux and its role in drug resistance, which will enable the identification of new drug targets and development of new drug regimens to counteract the drug efflux mechanism of MTB

Effect of early tranexamic acid administration on mortality, hysterectomy, and other morbidities in women with post-partum haemorrhage (WOMAN): an international, randomised, double-blind, placebo-controlled trial

Background Post-partum haemorrhage is the leading cause of maternal death worldwide. Early administration of tranexamic acid reduces deaths due to bleeding in trauma patients. We aimed to assess the effects of early administration of tranexamic acid on death, hysterectomy, and other relevant outcomes in women with post-partum haemorrhage. Methods In this randomised, double-blind, placebo-controlled trial, we recruited women aged 16 years and older with a clinical diagnosis of post-partum haemorrhage after a vaginal birth or caesarean section from 193 hospitals in 21 countries. We randomly assigned women to receive either 1 g intravenous tranexamic acid or matching placebo in addition to usual care. If bleeding continued after 30 min, or stopped and restarted within 24 h of the first dose, a second dose of 1 g of tranexamic acid or placebo could be given. Patients were assigned by selection of a numbered treatment pack from a box containing eight numbered packs that were identical apart from the pack number. Participants, care givers, and those assessing outcomes were masked to allocation. We originally planned to enrol 15 000 women with a composite primary endpoint of death from all-causes or hysterectomy within 42 days of giving birth. However, during the trial it became apparent that the decision to conduct a hysterectomy was often made at the same time as randomisation. Although tranexamic acid could influence the risk of death in these cases, it could not affect the risk of hysterectomy. We therefore increased the sample size from 15 000 to 20 000 women in order to estimate the effect of tranexamic acid on the risk of death from post-partum haemorrhage. All analyses were done on an intention-to-treat basis. This trial is registered with ISRCTN76912190 (Dec 8, 2008); ClinicalTrials.gov, number NCT00872469; and PACTR201007000192283. Findings Between March, 2010, and April, 2016, 20 060 women were enrolled and randomly assigned to receive tranexamic acid (n=10 051) or placebo (n=10 009), of whom 10 036 and 9985, respectively, were included in the analysis. Death due to bleeding was significantly reduced in women given tranexamic acid (155 [1·5%] of 10 036 patients vs 191 [1·9%] of 9985 in the placebo group, risk ratio [RR] 0·81, 95% CI 0·65–1·00; p=0·045), especially in women given treatment within 3 h of giving birth (89 [1·2%] in the tranexamic acid group vs 127 [1·7%] in the placebo group, RR 0·69, 95% CI 0·52–0·91; p=0·008). All other causes of death did not differ significantly by group. Hysterectomy was not reduced with tranexamic acid (358 [3·6%] patients in the tranexamic acid group vs 351 [3·5%] in the placebo group, RR 1·02, 95% CI 0·88–1·07; p=0·84). The composite primary endpoint of death from all causes or hysterectomy was not reduced with tranexamic acid (534 [5·3%] deaths or hysterectomies in the tranexamic acid group vs 546 [5·5%] in the placebo group, RR 0·97, 95% CI 0·87-1·09; p=0·65). Adverse events (including thromboembolic events) did not differ significantly in the tranexamic acid versus placebo group. Interpretation Tranexamic acid reduces death due to bleeding in women with post-partum haemorrhage with no adverse effects. When used as a treatment for postpartum haemorrhage, tranexamic acid should be given as soon as possible after bleeding onset. Funding London School of Hygiene & Tropical Medicine, Pfizer, UK Department of Health, Wellcome Trust, and Bill & Melinda Gates Foundation

Analysis and Implementation of Human Mobility Behavior Using Similarity Analysis Based on Co-Occurrence Matrix

The fast expansion of ICT (information and communications technology) has provided rich sources of data for the analysis, modeling, and interpretation of human mobility patterns. Many researchers have already introduced behavior-aware protocols for a better understanding of architecture and realistic modeling of behavioral characteristics, similarities, and aggregation of mobile users. We are introducing the similarity analytical framework for the mobile encountering analysis to allow for more direct integration between the physical world and cyber-based systems. In this research, we propose a method for finding the similarity behavior of users’ mobility patterns based on location and time. This research was conducted to develop a technique for producing co-occurrence matrices of users based on their similar behaviors to determine their encounters. Our approach, named SAA (similarity analysis approach), makes use of the device info i.e., IP (internet protocol) and MAC (media access control) address, providing an in-depth analysis of similarity behaviors on a daily basis. We analyzed the similarity distributions of users on different days of the week for different locations based on their real movements. The results show similar characteristics of users with common mobility behaviors based on location and time to showcase the efficacy. The results show that the proposed SAA approach is 33% more accurate in terms of recognizing the user’s similarity as compared to the existing similarity approach

Synthesis of new N-(5-chloro-2-methoxyphenyl)-4-(5-substituted-1,3,4-oxadiazol-2-ylthio)butanamide derivatives as suitable lipoxygenase inhibitors

Heterocyclic compounds are the most attractive class for researchers due to their biological activities. In the undertaken research, a number of N-(5-chloro-2-methoxyphenyl)-4-(5-substituted-1,3,4-oxadiazol-2-ylthio)butanamide (6a–k) compounds were prepared by converting multifarious phenyl/aryl/aralkyl/heterocyclic organic acids (1a–k) consecutively into the corresponding esters (2a–k), hydrazides (3a–k) and 5-substituted-1,3,4-oxadiazol-2-thiols (4a–k). Finally, the target compounds 6a–k were synthesized by stirring 5-substituted-1,3,4-oxadiazol-2-thiols (4a–k) with N-(5-chloro-2-methoxyphenyl)-4-bromobutanamide (5) in the presence of N,N-dimethylformamide (DMF) and sodium hydride (NaH). The structure elucidation of the synthesized compounds was processed through 1H-NMR, IR and mass spectral data. The synthesized compounds were screened against lipoxygenase enzyme (LOX) and showed moderately good activities relative to the reference standard Baicalein

Multifunctional Electrically Conductive Copper Electroplated Fabrics Sensitizes by In-Situ Deposition of Copper and Silver Nanoparticles

In this study, we developed multifunctional and durable textile sensors. The fabrics were coated with metal in two steps. At first, pretreatment of fabric was performed, and then copper and silver particles were coated by the chemical reduction method. Hence, the absorbance/adherence of metal was confirmed by the deposition of particles on microfibers. The particles filled the micro spaces between the fibers and made the continuous network to facilitate the electrical conduction. Secondly, further electroplating of the metal was performed to make the compact layer on the particle- coated fabric. The fabrics were analyzed against electrical resistivity and electromagnetic shielding over the frequency range of 200 MHz to 1500 MHz. The presence of metal coating was confirmed from the surface microstructure of coated fabric samples examined by scanning electron microscopy, EDS, and XRD tests. For optimized plating parameters, the minimum surface resistivity of 67 Ω, EMI shielding of 66 dB and Ohmic heating of 118 °C at 10 V was observed. It was found that EMI SH was increased with an increase in the deposition rate of the metal. Furthermore, towards the end, the durability of conductive textiles was observed against severe washing. It was observed that even after severe washing there was an insignificant increase in electrical resistivity and good retention of the metal coating, as was also proven with SEM images

Biochemical Analysis of Organic Acids and Soluble Sugars in Wild and Cultivated Pomegranate Germplasm Based in Pakistan

Pomegranate is famous for its health benefiting chemical and biochemical constituent compounds. The present study was undertaken to characterize pomegranate germplasm for its various fruit traits, acids, and sugar profiling through high performance liquid chromatography (HPLC) analysis. Among 11 detected acids and 8 sugars, citric acid and fructose were predominant in 18 domestic and 5 wild genotypes, respectively. Fruit weight, aril weight and wood portion index (WPI) were ranged from 15.82% to 24.42%, 10.99% to 113.78%, and 2.39% to 17.25%, respectively. Genotypes were grouped as sweet, sweet–sour, sour–sweet, and sour based on citric acid contents. Lactic acid and pyruvic acid showed the highest correlation (r = 0.92), however, sour and sweet genotypes had strong association for acids and sugars, respectively. Straddling of dendrogram showed the flow of genetic material in a cultivated location with wild and cultivated pomegranates grouped in different classes, however, wild and sour landraces grouped in the same class with 71% similarity of traits. Based on the observations of the current study, it was concluded that selected wild and arid zones (Multan, Bahawalpur) genotypes are poor in nutrients (acid and sugars) quality, however, genotypes of Rahim-Yar-Khan, Muzafar Garh, and Khyber Pakhtunkhwa have a better composition of sugars and acids

Flaxseed (Linum usitatissimum); phytochemistry, pharmacological characteristics and functional food applications

Flaxseed (Linum usitatissimum) from the family Linaceae, is a valuable medicinal oil seed crop cultivated all around the world. Presence of proteins, dietary fiber, fatty acids, especially α-linolenic acid, vitamins, minerals, phenolics, flavonoids and other bioactive components in significant amounts, enhances medicinal, pharma food and commercial value of flaxseed. It has been added in a variety of bakery items, beverages and dairy products. Moreover, consumption of flaxseed upsurge due to its risk lowering ability of numerous degenerative (diabetes, obesity) and chronic disorders (cardiovascular diseases and cancer). Flaxseed also has prebiotic properties and improve the health of gut microbiota. Additionally, flaxseed also contains several antinutrients such as phytic acid, protease inhibitors, and cyanogenic glycosides, which can limit the bioavailability of certain essential nutrients and can reduce nutritional value. Flaxseed meal interactions, dosage and supplementations have also been discussed. The focus of the current review is on recent studies on humans and animals as well as flaxseed's commercial use in a variety of food products as proof of its phytochemical content and potential health benefits