Conformation Controlled Hydrogelation of Minimalistic α, γ Hybrid Peptide.

A majority of short peptide (≤7 amino acids) hydrogels are primarily assembled via cross ß-structure formation. In contrast to the natural trend, herein, we report the formation of supramolecular hydrogel from the ultrashort hybrid folded peptide composed of canonical α-amino acid and noncanonical γ-amino acid, Fmoc-γPhe-Phe-OH. The designed hybrid peptide hydrogel is composed of entangled fibers, has viscoelastic properties, exhibits proteolytic stability, and exhibits cytocompatibility with L929 fibroblast cells. Mutating the peptide sequence by altering the position of γPhe from the N-termini to C-termini transforms the self-assembly into crystalline aggregates. Combining FTIR, 2D NMR, and DFT calculations revealed that the hydrogel-forming peptide adopts a C9 H-bonded conformation, resembling the well-known γ-turn. However, the isomeric hybrid peptide adopts an extended structure. The present study highlights the importance of secondary structure in the higher order assembly of minimalist hybrid peptides and broadens the range of secondary structures to design short peptide-based hydrogels.

Designing Pathway-Controlled Multicomponent Ultrashort Peptide Hydrogels with Diverse Functionalities at the Nanoscale for Directing Cellular Behavior.

Tuning self-assembling pathways by implementing different external stimuli has been extensively studied, owing to their effective control over structural and mechanical properties. Consequently, multicomponent peptide hydrogels with high structural tunability and stimuli responsiveness are crucial in dictating cellular behavior. Herein, we have implemented both coassembly approach and pathway-dependent self-assembly to design nonequilibrium nanostructures to understand the thermodynamic and kinetic aspects of peptide self-assembly toward controlling cellular response. Our system involved an ultrashort peptide gelator and a hydrophilic surfactant which coassembled through different pathways, i.e., heat-cool and sonication methods with variable energy input. Interestingly, it was possible to access diverse structural and mechanical properties at the nanoscale in a single coassembled system. Further, the hydrophilic surfactant provided additional surface functionalities, thus creating an efficient hydrophilic matrix for cellular interaction. Such diverse functionalities in a single coassembled system could lead to the development of advanced scaffolds, with applications in various biomedical fields.

Designing Cardin-Motif Peptide and Heparin-Based Multicomponent Advanced Bioactive Hydrogel Scaffolds to Control Cellular Behavior.

Recently, peptide and sugar-based multicomponent systems have gained much interest in attaining the sophisticated structure and biofunctional complexity of the extracellular matrix (ECM). To this direction, we have designed for the first time a biologically relevant minimalist Cardin-motif peptide capable of binding ECM-derived glycosaminoglycans. Herein, we explored Cardin-motif peptide and heparin-based biomolecular matrix by employing simple noncovalent interactions at the molecular level. Interestingly, this peptide was inadequate to induce hydrogelation at ambient pH due to the presence of basic amino acids. However, addition of heparin successfully triggered its gelation at physiological pH following favorable electrostatic interactions with heparin. Importantly, the newly developed scaffolds displayed tunable nanofibrous morphology and superior mechanical properties as controlled simply by the differential mixing ratio of both biomolecular entities. Additionally, these composite scaffolds could closely mimic the complexity of ECM as they demonstrated superior biocompatibility and enhanced growth and proliferation of neural cells as compared to the peptide scaffold.

COVID-19 Pandemic in Malegaon: SUTRA over the Three Waves.

Over the past two years, the COVID-19 pandemic has seen multiple waves with high morbidity and mortality. Lockdowns and other prompt responses helped India's situation become less severe. Although Malegaon in the Indian state of Maharashtra has a high population density, poor hygienic standards, and oppositional local community views toward national pandemic addressing measures, it is nevertheless reasonably safe. To understand the possible reasons serosurvey was conducted to estimate the anti-SARS-CoV-2 neutralizing antibody levels in the Malegaon population. Also, we did SUTRA mathematical modeling to the Malegaon daily data on COVID-19 attributable events and compared it with the National and state level. The case fatality rate (CFR) in Malegaon city for the first, second, and third waves was 3.25%, 2.25%, and 0.39%, respectively. The crude death rate (CDR) for Maharashtra ranked first for the initial two waves and India for the third wave. Malegaon, meanwhile, finished second in the first two waves but fared best in the third. The Vaccination coverage for the first dose before the second wave was only 0.34% but had risen to 64.46% by 12 Oct 2022. By then, the second and booster dose coverage was 27.55% and 2.38%, respectively. Serosurvey did between 12 and 18 Jan 2022 showed a 93.93% anti-SARS-CoV-2 neutralizing antibody presence. SUTRA modeling elucidated the high levels of antibodies due to the pandemic-reach over 102% by the third wave. The serosurvey and the model explain why the pandemic severity in terms of duration and CFR during the subsequent waves, especially third wave, was milder compared to the first wave in spite of low vaccination rates. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-023-01096-3.

Exploring Supramolecular Interactions between the Extracellular-Matrix-Derived Minimalist Bioactive Peptide and Nanofibrillar Cellulose for the Development of an Advanced Biomolecular Scaffold.

It has been increasingly evident over the last few years that bioactive peptide hydrogels in conjugation with polymer hydrogels are emerging as a new class of supramolecular materials suitable for various biomedical applications owing to their specificity, tunability, and nontoxicity toward the biological system. Despite their unique biocompatible features, both polymer- and peptide-based scaffolds suffer from certain limitations, which restrict their use toward developing efficient matrices for controlling cellular behavior. The peptide hydrogels usually form soft matrices with low mechanical strength, whereas most of the polymer hydrogels lack biofunctionality. In this direction, combining polymers with peptides to develop a conjugate hydrogel can be explored as an emergent approach to overcome the limitations of the individual components. The polymer will provide high mechanical strength, whereas the biofunctionality of the material can be induced by the bioactive peptide sequence. In this study, we utilized TEMPO-oxidized nanofibrillar cellulose as the polymer counterpart, which was co-assembled with a short N-cadherin mimetic bioactive peptide sequence, Nap-HAVDI, to fabricate an NFC-peptide conjugate hydrogel. Interestingly, the mechanical strength of the peptide hydrogel was found to be significantly improved by combining the peptide with the NFC in the conjugate hydrogel. The addition of the peptide into the NFC also reduced the pore size within NFC matrices, which further helped in improving cellular adhesion, survival, and proliferation. Furthermore, the cells grown on the NFC and NFC-peptide hybrid hydrogel demonstrated normal expression of cytoskeleton proteins, i.e., ß-tubulin in C6 cells and actin in L929 cells, respectively. The selective response of neuronal cells toward the specific bioactive peptide was further observed through a protein expression study. Thus, our study demonstrated the collective role of the cellulose-peptide composite material that revealed superior physical properties and biological response of this composite scaffold, which may open up a new platform for biomedical applications.

SARS-CoV-2 Pandemic-Therapeutics in Warp Speed.

Ever since the coronavirus disease 2019 (COVID-19) pandemic struck, the challenges posed to the scientific community by its causative agent, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been countless, and still continue to emerge. Even though a host of repurposed and new therapeutic agents as well as vaccines have been, and are being assessed at a breakneck speed, this contagion continues to create havoc, returning back in waves, with appearance of newer viral variants which are associated with numerous challenges, which include greater transmissibility, increased virulence, immune escape, etc. In this study, we discuss the current status of various therapeutic agents which are being used, or in the various stages of preclinical/clinical trials for managing COVID-19.

Biomass-derived cellulose nanofibers and iron oxide-based nanohybrids for thermal insulation application.

In recent years, due to high energy consumption in the building sector and subsequent environmental issues, environment-friendly and cost-effective thermally insulating materials are in high demand to improve the energy efficiency of buildings. Current commercially available thermal insulating materials (polystyrene) always pose a challenge due to their non-biodegradability and poor insulating performance. To this end, biomass-derived aerogels are attracting significant interest as renewable and sustainable insulating materials. In this work, we have developed a facile strategy for synthesizing cellulose nanofibers from biomass-derived wood pulp as a cost-effective starting material by TEMPO-oxidation, and further incorporating iron oxide nanoparticles to make a nanohybrid. Interestingly, in these nanohybrids, the functional attributes like mechanical strength and flammability were improved to a great extent and thus overcoming the limitations of the commercially available thermal insulating materials in terms of their stability and durability. Most importantly, these nanohybrids demonstrated very low thermal conductivity, as low as 0.024 W m-1 K-1, indicating the better insulating potential of these nanohybrids as compared to other conventional insulating materials.

Evaluation of a novel sputum processing ReaSLR methodology for improving sensitivity of smear microscopy in clinical samples.

Background: Early case detection is a crucial step in the control of tuberculosis (TB). Sputum smear microscopy is the primary method of TB diagnosis in developing countries. The modified Petroff's method using sodium hydroxide at concentrations ranging between 2% and 4% to digest the specimen is widely used in developing countries. A novel ReaSLR (ReaMetrix's Sputum Liquefying Reagent) methodology has been proposed as a simple, easy, low-cost, and better alternative to conventional methods for sputum processing. This study was undertaken to evaluate the performance of the ReaSLR method of sputum processing in comparison with that of the modified Petroff's method. Methods: Early-morning sputum samples were collected. After preparing a direct smear, each sample was divided into two equal halves and processed by both the methods, i.e., modified Petroff's method and ReaSLR method. Direct smears were graded according to Revised National Tuberculosis Control Program grading, and smears prepared after processing by the two different methods were graded according to Center for Disease Control and Prevention grading. Smear microscopy results were compared taking culture results of samples processed by the modified Petroff's method as the gold standard. Results: The rate of smear positivity with the modified Petroff's method (22.22%) was found to be higher than that with direct smear microscopy (13.56%; p = 0.0002) and the ReaSLR method (17.32%; p = 0.04). The modified Petroff's method was found to be 26.76% more sensitive than direct microscopy and 15.59% more sensitive than the ReaSLR method. Conclusion: The ReaSLR method was not superior to the modified Petroff's method for smear microscopy. Although this method was more sensitive than the direct method in smear microscopy, the modified Petroff's method performed much better than the ReaSLR method.

Post vaccination antibody titres of hepatitis B surface antigen (anti-HBs) in a mixed cohort of health care workers.

Background: Hepatitis B (HepB) is an important vaccine preventable infection among healthcare workers (HCWs). Vaccination against Hep B virus, remains the foremost preventive approach. This study aims to measure the antibody titres to Hep B surface antigen (anti-HBs) in a mixed cohort of HCWs. It also aims to study the association between time since vaccination and the anti-HBs titres thus evaluating the duration of seroprotection. Methods: A total of 200 HCWs, including nursing students (n = 112), nursing staff (n = 49), laboratory technicians (n = 30) and doctors (n = 9) who had received all three doses of the Hep B vaccine and met the inclusion criteria of having taken all three doses of vaccine were included in this study. Anti-HBs titres were estimated by bioMérieux mini VIDAS® automated immunoassay based on the principle of enzyme-linked fluorescence assay. Results: Two hundred subjects aged 19 to 52 years were included in the study; mean age was 27.29 ± 0.568 years. Duration since vaccination in the study cohort was ≤ 5 years in 149 (74.5.0%), 6-10 years in 20 (10.0%) and >10 years in 31 (15.5%) subjects. Postvaccination antibody titres were > 100 mIU/ml in 85.0%, 10-100 mIU/ml in 11.0% and ≤ 10 mIU/ml in 3.5%. There was a decline noted in antibody titres as duration after vaccination increased. Increasing age was associated with falling protective titres. Conclusion: The study revealed that majority of the HCWs had adequate anti-HBs titres and were protected after vaccination.

Prozone phenomenon in secondary syphilis with HIV co-infection: Two cases.

Prozone phenomenon is defined as a false-negative response resulting from higher antibody titer which interferes with formation of antigen-antibody lattice, necessary to visualize a positive flocculation test. The prozone effect can be observed in syphilis testing with cases of very high antibody titers, such as secondary syphilis, or with human immunodeficiency virus (HIV) co-infection. We report two cases of prozone phenomenon in secondary syphilis with HIV co-infection who initially tested nonreactive for rapid plasma reagin test but tested positive with further higher dilution.

Effectiveness of ChAdOx1 nCOV-19 Vaccine: Experience of a tertiary care institute.

BACKGROUND: The first dose of the ChAdOx1 nCoV- 19 Corona Virus Vaccine (Covishield) was administered to the eligible beneficiaries of tertiary care institute of Western Maharashtra on 16 Jan 21 and in the past three months almost 97% of the staff has been vaccinated. The present study analyses the incidence of COVID cases in the unvaccinated and vaccinated population of the institute. METHODS: All Covid 19 infections (RT-PCR positive) from 01 February 21 to 25 April 21 were included in the study and analyzed as per their vaccination status. To assess the COVID 19 transmission in contacts, Secondary Attack Rates (SAR) of the pre-vaccination period (Jun-Oct 20) was compared with the present SAR. RESULTS: A total of 113 cases occurred in the study period (01 Feb to 25 Apr 21). Lower number of infections were observed among the fully vaccinated as compared to partially vaccinated and non-vaccinated. The overall vaccine effectiveness was found to be 88.6% (81.55-92.37) and 44.1% (4.55-67.3) in completely and partially vaccinated individuals respectively. Hazard Ratios for getting infected dropped significantly after 28 days of the second dose. The SAR in high risk contacts (HRCs) was found to be 4.25%, which was lower than SAR (20.6%) of pre-vaccination period. CONCLUSION: This is one of the earliest studies in India to report the impact of COVID-19 vaccination. The results indicate that the vaccine provides effective protection against COVID-19 infection. However, given the complex dynamics of vaccination, the role of NPIs and implementation of COVID appropriate behavior cannot be undermined.

Estimating the proportion and IgG antibody response to SARS-CoV-2 in individuals joining a central educational institute from different parts of India by Enzyme-linked immunosorbent assay (ELISA) based serology.

BACKGROUND: Antibody response to SARS-CoV may be estimated to give trends and patterns emerging in a population during an evolving epidemic. The novel coronavirus has opened a new chapter in the history of pandemics and understanding the disease epidemiology. METHODS: The study was a cross-sectional descriptive study. Institutional Ethical clearance and informed consent were taken for participation in the study. The study population included all personnel reporting to the institute for training courses, permanent posting or joining back from leave during the study period of 2 months (16 June to 16 August 2020). The sample size was calculated assuming the prevalence of COVID-19 to be 1% with the absolute precision of 0.5% and 5% level of significance, and finite correction for population size of 500, and the calculated sample size was 377. Inclusion criteria were all personnel reporting to the institute from different states and districts. Exclusion criteria-Any personnel reported for a short visit of lesser than 14 days. Demographic details and details of any likely exposure to a confirmed COVID-19 case were noted. A blood sample was collected, and serological tests were done using ErbaLisa COVID-19 IgG kit by Calbiotech, as per the manufacturer's instructions. RESULTS: Overall seropositivity of IgG COVID-19 antibodies was 7.5% (31/413) (95% CI: 5.3-10.4%). Study population (n = 413) comprised of an adult population in the age range of 21 years-53 years, and the mean age was 31.4 years (SD = 6.2 years). CONCLUSION: As the personnel joining the institute have come from various parts of the country the study provides an estimation of antibodies against COVID-19.

Probable vertical transmission of severe acute respiratory syndrome coronavirus 2 infection from mother to neonate.

The pandemic spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has affected 188 countries and territories. Altered physiological status during pregnancy makes a mother vulnerable to severe SARS-CoV-2 infection. The virus may be transmitted from mother to baby during antenatal period or postnatal period. Although the primary mode of transmission of the virus is by respiratory droplets, there is emerging evidence of in utero transmission from mother to foetus. In this rare case report, we describe one such episode of probable vertical transmission. To the best of our knowledge, this is the second systematically investigated Indian case, indicating in utero transmission of SARS-CoV-2 from mother to foetus.

Whole genome sequence of colistin-resistant Escherichia coli from western India.

BACKGROUND: With virtually dried out new antibiotic discovery pipeline, emergence and spread of antimicrobial resistance is a cause for global concern. Colistin, a cyclic polypeptide antibiotic, often regarded as last resort for multi drug resistance gram-negative bacteria, is also rendered ineffective by horizontal transfer of resistance genes. Surveillance of colistin resistance in GNB is essential to ascertain molecular epidemiology. METHODS: Whole genome sequencing (WGS) of an unusual colistin resistant urinary isolate of Escherichia coli was performed using Illumina MiSeq platform using 2x250bp V2 chemistry by following the manufactures protocol (Illumina Inc. USA). Multiple web-based bio-informatic tools were utilized to ascertain antibiotic resistant genes. RESULTS: An approximate 5.4 Mb of genome of the urinary isolate AFMC_UC19 was sequenced successfully. Mobile colistin resistance gene (mcr) on the plasmid responsible for horizontal spread was absent in the isolate. CONCLUSION: Colistin resistance has been reported previously in Klebsiella pneumoniae and it is a rare occurrence in Escherichia coli in Indian setting. Although the isolate lack mcr mediated colistin resistance, emergence and spread of colistin resistant in gram-negative bacteria pose a threat.

Genotypic characterization of carbapenem resistant Enterobacterales in clinical isolates from western Maharashtra.

PURPOSE: To study distribution of carbapenemase genes namely; New Delhi metallo-beta-lactamase (blaNDM), Oxacillinase-48 (blaOXA48), Verona Integron-Encoded Metallo-beta-lactamase (blaVIM) and Imipenemase (blaIMP) in carbapenem resistant Enterobacterales (CRE), isolated from clinical samples. METHOD: This cross-sectional study was conducted at a tertiary care hospital of western Maharashtra over six months period. CREs were identified by conventional disc diffusion and modified carbapenem inactivation method (mCIM). A total of 50 consecutive CRE isolates from clinical samples were subjected to home brewed polymerase chain reaction (PCR) for detection of carbapenemases. RESULTS: Out of the 50 CRE isolates, at least one of the four carbapenemase genes was detected in 49 (98%) isolates. The frequency of distribution of these genes were NDM 90% (n = 45), OXA48 60% (n = 30) and VIM 12% (n = 6). Dual combination of blaNDM and blaOXA48 (50%) was the commonest pattern observed, which was frequently associated with Klebsiella pneumoniae. CONCLUSIONS: The study indicate high prevalence of NDM warranting strict anti-microbial stewardship practices. Surveillance of CRE and resistance mechanism is essential to monitor the trend and take informed decision for appropriate anti-microbial therapy.

Analysis for different functional results of TMJ ankylosis management by comparing ramus-condyle unit reconstruction using vertical ramus osteotomy and interpositional gap arthroplasty.

OBJECTIVE: The objective of the present study was to analyze the functional results of temporomandibular joint (TMJ) range; that is, trismus index, lateral excursion, protrusion, retrusion, occlusion, masticatory efficiency), reestablishment of the anatomic relationship of the TMJ, aesthetics to improve quality of life, and complications in terms of ramus shortening on the affected side, deviation, facial asymmetry, neurologic deficits, and reankylosis. STUDY DESIGN: Sixteen patients with unilateral bony ankylosis were included and randomly divided into 2 groups with 8 patients in each group. Group I was treated with interpositional gap arthroplasty followed by reconstruction of the ramus-condyle unit using vertical ramus osteotomy. Group II was treated with interpositional gap arthroplasty. In both groups, a pedicled flap made up of fascia, temporalis muscle, and pericranium was used as an interpositional material. The functional range of the mandible was analyzed pre- and postoperatively. RESULTS: Group I improved significantly more than group II in terms of TMJ range; that is, trismus index, lateral excursion, protrusion, retrusion, reestablishment of the normal anatomic relationship of the TMJ, aesthetics, and masticatory efficiency. The reestablishment of anatomic relationship showed better result in mastication significantly. No reankylosis was reported in any of the groups. CONCLUSION: The functional results and aesthetics with TMJ reconstruction are significantly better.

Atrial fibrillation following low voltage electrical injury.

Electrical injuries can have myriad presentations, including significant cardiac involvement. Arrhythmias are the most frequently experienced cardiac affliction, of which sinus tachycardia or bradycardia, ventricular fibrillation, atrial or ventricular premature beats and bundle branch block are most commonly reported. A 50-year-old man, with no prior history of cardiac disease, presented with palpitations following low voltage electrical injury. On examination, he was tachycardic with an irregularly irregular pulse. An ECG confirmed atrial fibrillation with rapid ventricular rate. Chemical cardioversion was attempted successfully, following which the patient reverted to sinus rhythm. Atrial fibrillation following electrical injury has been rarely described in the literature, and is rarer so without associated high voltage electrical exposure or pre-existing cardiac ailment.

Immune activation markers in individuals with HIV-1 disease and their correlation with HIV-1 RNA levels in individuals on antiretroviral therapy.

BACKGROUND: Currently CD4+ T lymphocyte counts and HIV-1 RNA levels are being utilized to predict outcome of human immunodeficiency virus (HIV) disease. Recently, the role of immune activation in HIV disease progression and response to treatment is being investigated. This study focused on the expression of CD38 and HLA-DR on lymphocyte subsets in various groups of HIV-infected individuals and to determine their association with HIV-1 disease progression. METHODS: Ninety-eight cases of patients with HIV/AIDS in different disease stages and twenty-four healthy HIV-negative individuals were included in the cross-sectional study. Their immune function and abnormal immune activation markers (CD38 & HLA-DR) were detected using a flowcytometer, and HIV-1 RNA levels in individuals receiving antiretroviral drugs were estimated. RESULTS: The immune activation marker levels were significantly different between patients with different disease stages (P < 0.001). A significant negative correlation was observed between peripheral blood CD4+ T cell counts and immune activation markers. Also, a significant positive correlation was observed between HIV-1 RNA levels and CD38+CD8+ T lymphocyte. CONCLUSION: Immune activation markers (CD38 & HLA-DR) increase with disease progression. CD38+ on CD8+ T lymphocyte correlates well with HIV1 RNA levels in individuals failing on antiretroviral therapy.