The latent reservoir of inducible, infectious HIV-1 does not decrease despite decades of antiretroviral therapy

HIV-1 persists in a latent reservoir in resting CD4+ T cells despite antiretroviral therapy (ART). The reservoir decays slowly over the first 7 years of ART (t1/2 = 44 months). However, whether decay continues with long-term ART is unclear. Recent integration site studies indicate gradual selection against inducible, intact proviruses, raising speculation that decades of ART might allow treatment interruption without viral rebound. Therefore, we measured the reservoir in 42 people on long-term ART (mean 22 years) using a quantitative viral outgrowth assay. After 7 years of ART, there was no long-term decrease in the frequency of inducible, replication-competent proviruses but rather an increase with an estimated doubling time of 23 years. Another reservoir assay, the intact proviral DNA assay, confirmed that reservoir decay with t1/2 of 44 months did not continue with long-term ART. The lack of decay reflected proliferation of infected cells. Most inducible, replication-competent viruses (79.8%) had env sequences identical to those of other isolates from the same sample. Thus, although integration site analysis indicates changes in reservoir composition, the proliferation of CD4+ T cells counteracts decay, maintaining the frequency of inducible, replication-competent proviruses at roughly constant levels over the long term. These results reinforce the need for lifelong ART.

A cross sectional analysis of medical device associated adverse events with radiotherapy devices - A materiovigilance study

BACKGROUND

Materiovigilance is a method for tracking, documenting, and analyzing the causal factors of adverse outcomes or complications associated with the use of medical devices. In addition, it recommends that the Indian regulatory authority takes necessary steps with the aim of enhancing patient safety. The present study was taken up as there are hardly any studies available in the public domain on adverse events due to radiotherapy.

OBJECTIVE

The objective of the study is to analyze the pattern of adverse events due to medical devices used in the department of radiation oncology.

METHODS

It was a cross-sectional study carried out from June to September, 2022. The patients who were treated with the medical devices in radiation oncology at Victoria Hospital affiliated with Bangalore Medical College and Research Institute, Bengaluru, were included. The medical device used on the patients causes adverse events. The data were collected from the patient's health records available in the department of radiotherapy.

RESULTS

Total 40 adverse events collected as per inclusion and exclusion criteria were analyzed. All the adverse events associated with medical devices were filled in the medical device adverse event reporting form and submitted to materiovigilance program, which also included the causality assessment. All the adverse events were caused due to external beam radiotherapy/teletherapy device. Dermatitis was the most common adverse event found in the reported cases (n = 20, 50%).

CONCLUSION

Materiovigilance program is in budding stage. It was observed that the adverse events in patients were due to medical devices used in radiation oncology. Medical devices with skin-sparing effect (radiation is converged onto tumor) should be promoted and more research and engineering are required in designing of advanced medical devices for the treatment of cancer across the globe.

Characterization and biocontrol potential of a naturally occurring isolate of Metarhizium pingshaense infecting Conogethes punctiferalis

An entomopathogenic fungus was isolated from an infected larva of Conogethes punctiferalis (Guenée) (Crambidae: Lepidoptera), a highly polyphagous pest recorded from more than 120 plants and widely distributed in Asia and Oceanic countries. The fungus was identified as Metarhizium pingshaense Q.T. Chen & H.L. Guo (Ascomycota: Hypocreales) based on morphological characteristics and molecular studies. Scanning electron microscopic studies were conducted to study the infection of C. punctiferalis by M. pingshaense. Bioassay studies with purified conidial suspension proved that the isolate was highly virulent to C. punctiferalis, causing more than 86 % mortality to fifth instar larvae at 1 × 10⁸ spores/mL, under laboratory conditions. The median lethal concentration (LC₅₀) of the fungus against late instar larvae was 9.1 × 10⁵ conidia/mL and the median survival time (MST) of late instar larvae tested at the doses of 1 × 10⁸ and 1 × 10⁷ conidia/mL were 4.7 and 6.4 days, respectively. The optimal temperature for fungal growth and sporulation was found to be 25 ± 1 °C. This is the first report of M. pingshaense naturally infecting C. punctiferalis. Isolation of a highly virulent strain of this fungus holds promise towards development of a potential mycoinsecticide against this pest.

Glycosylation as a tool for rational vaccine design

The discovery of broadly neutralizing antibodies that can neutralize multiple strains or subtypes of a pathogen has renewed interest in the development of broadly protective vaccines. To that end, there has been an interest in designing immunofocusing strategies to direct the immune response to specific, conserved regions on antigenic proteins. Modulation of glycosylation is one such immunofocusing strategy; extensive glycosylation is often exploited by pathogens for immune evasion. Masking epitopes on protein immunogens with "self" glycans can also shield the underlying protein surface from humoral immune surveillance. We review recent advances in applying glycosylation as an immunofocusing tool. We also highlight recent interesting work in the HIV-1 field involving the identification and elicitation of broadly neutralizing antibodies that incorporate glycans into their binding epitopes.

Nanopatterning protein antigens to refocus the immune response

Vaccines for many important diseases remain elusive, and those for others need to be updated frequently. Vaccine efficacy has been hindered by existing sequence diversity in proteins and by newly-acquired mutations that enable escape from vaccine-induced immune responses. To address these limitations, we developed an approach for nanopatterning protein antigens that combines the site-specific incorporation of non-canonical amino acids with chemical modification to focus the immune response on conserved protein regions. We demonstrated the approach using green fluorescent protein (GFP) as a model antigen and with a promising malaria vaccine candidate, Merozoite surface protein 119 (MSP119). Immunization of mice with nanopatterned MSP119 elicited antibodies that recognized MSP119 from heterologous strains, differing in sequence at as many as 21 of 96 residues. Nanopatterning should enable the elicitation of broadly protective antibodies against a wide range of pathogens and toxins.

Reversal of intramyocellular lipid accumulation by lipophagy and a p62-mediated pathway

We have previously observed the reversal of lipid droplet deposition in skeletal muscle of morbidly obese patients following bariatric surgery. We now investigated whether activation of autophagy is the mechanism underlying this observation. For this purpose, we incubated rat L6 myocytes over a period of 6 days with long-chain fatty acids (an equimolar, 1.0 mM, mixture of oleate and palmitate in the incubation medium). At day 6, the autophagic inhibitor (bafilomycin A1, 200 nM) and the autophagic activator (rapamycin, 1 μM) were added separately or in combination for 48 h. Intracellular triglyceride (TG) accumulation was visualized and quantified colorimetrically. Protein markers of autophagic flux (LC3 and p62) and cell death (caspase-3 cleavage) were measured by immunoblotting. Inhibition of autophagy by bafilomycin increased TG accumulation and also increased lipid-mediated cell death. Conversely, activation of autophagy by rapamycin reduced both intracellular lipid accumulation and cell death. Unexpectedly, treatment with both drugs added simultaneously resulted in decreased lipid accumulation. In this treatment group, immunoblotting revealed p62 degradation (autophagic flux), immunofluorescence revealed the colocalization of p62 with lipid droplets, and co-immunoprecipitation confirmed the interaction of p62 with ADRP (adipose differentiation-related protein), a lipid droplet membrane protein. Thus the association of p62 with lipid droplet turnover suggests a novel pathway for the breakdown of lipid droplets in muscle cells. In addition, treatment with rapamycin and bafilomycin together also suggested the export of TG into the extracellular space. We conclude that lipophagy promotes the clearance of lipids from myocytes and switches to an alternative, p62-mediated, lysosomal-independent pathway in the context of chronic lipid overload (*P<0.05, **P<0.01, ***P<0.001, ****P<0.0001).

Heavy Metal Contamination in Groundwater around Industrial Estate vs Residential Areas in Coimbatore, India

INTRODUCTION

Water is the vital resource, necessary for all aspects of human and ecosystem survival and health. Depending on the quality, bore water may be used for human consumption, irrigation purposes and livestock watering. The quality of bore water can vary widely depending on the quality of ground water that is its source. Pollutants are being added to the ground water system through human and natural processes. Solid waste from industrial units is being dumped near the factories, which react with percolating rainwater and reaches the ground water. The percolating water picks up a large number of heavy metals and reaches the aquifer system and contaminates the ground water. The usage of the contaminated bore water causes the diseases. Mercury, Arsenic and Cadmium are used or released by many industries.

AIM

This study was conducted to investigate the pollution of bore water in the industrial region (Kurichi Industrial Cluster) of Coimbatore, in the state of Tamilnadu, India.

MATERIALS AND METHODS

Four samples were taken from residential areas around Kurichi Industrial Cluster and analysed to find the concentrations of Mercury, Arsenic and Cadmium. Four more samples were taken from other residential regions far from the industrial estate and served as control. Samples were analysed using Atomic absorption spectrophotometry method.

RESULTS

We found that the ground water of the areas surrounding the industrial cluster does not contain significant amount of those metals. Instead, Heavy metal contamination of ground water were observed in some residential areas of coimbatore.

CONCLUSION

The regulatory measures to contain and prevent ground water contamination by industries undertaken by Tamilnadu pollution control board may have lead to absence of heavy metal contamination in Kurichi Industrial cluster, Coimbatore, India.

Centralization of ulna for infected nonunion of radius with extensive bone loss. A modified Hey-Groves procedure

We describe a case of infected nonunion of the radius with extensive bone loss in an 11-year-old boy treated by centralization of the ulna. The technique used differs from the original Hey Groves procedure in that it preserves the distal end of the ulna with its important triangular fibrocartilage complex, thereby retaining stability and contour of the wrist joint. Our patient obtained a functionally and cosmetically satisfactory, stable forearm and wrist. We present the technique as a useful armament in the management of extensive bony defect of the radius arising from trauma or infection.

The value of ultrasound and aspiration in differentiating vaso-occlusive crisis and osteomyelitis in sickle cell disease patients

We have studied 50 patients with sickle cell disease who presented with musculoskeletal pain over a 2-year period to assess the use of ultrasound in differentiating infection from infarction. All the patients were evaluated by ultrasound. Five had soft tissue oedema and no fluid collection adjacent to the bone. Forty-five had a subperiosteal fluid collection. Twelve patients whose collections were not aspirated were diagnosed according to clinical evaluation. The remaining 33 patients underwent aspiration under ultrasound guidance to distinguish between an infection and infarction. Twenty-three of these were diagnosed as osteomyelitis and 10 as vaso-occlusive crises. In 21 out of the 23 infected cases, the fluid collection was greater than 10 mm at its thickest point perpendicular to the bone surface and all those with infarction had fluid less than 10 mm thickness. Aspiration under ultrasound guidance is a useful method to differentiate the two clinical entities. In patients suffering from osteomyelitis, identification of the organisms guides antibiotic administration. Needle decompression can help to relieve pain in osteomyelitis and vaso-occlusive crisis.

Spatial vectorcardiogram in acute inferior wall myocardial infarction: its utility in identification of patients prone to complete heart block

Spatial vectorcardiography was performed in 28 (22 males, 6 females; age 36-78 years) consecutive cases of acute inferior wall myocardial infarction during sinus rhythm within 24 hours of admission. Orthogonal leads using the corrected Frank lead system were recorded at a paper speed of 100 mm/sec. Qualitative analysis consisted of study of QRS loop inscription in all 3 orthogonal planes. Additional quantitative analysis using the spherical coordinate system was undertaken to measure the magnitude and angular direction (azimuth and elevation angle) of spatial R maximum cardiac vector. During the hospital course, 15 patients developed transient complete heart block and 13 patients did not. The direction of the QRS loop inscription in the 3 planes did not differ between the two groups. The spatial R maximum magnitude and azimuth angle did not differ between the patients who developed complete heart block and those who did not. Values for elevation angle were markedly different between the two groups. The spatial R maximum elevation angle ranged from 0 to -35 degrees and was negative (superiorly directed) in 14 of the 15 patients with complete heart block, whereas it ranged from -10 degrees to +/- 75 degrees and was negative (superiorly directed) in only 2 of the 13 patients without this complication. Thus it appears that negative elevation angle of spatial R maximum cardiac vector in patients with inferior wall myocardial infarction may indicate proneness to complete heart block.