Publications by authors named "Astha Joshi"

Airborne transmission via aerosols is a dominant route for the transmission of respiratory pathogens, including avian H5N1 influenza A virus and bacteria. Rapid and direct detection of respiratory pathogen aerosols has been a long-standing technical challenge. Herein, we develop a novel label-free capacitive biosensor using an interlocked Prussian blue (PB)/graphene oxide (GO) network on a screen-printed carbon electrode (SPCE) for direct detection of avian H5N1 and .

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Article Synopsis
  • - RNA-Puzzles is a collaborative project focused on improving the prediction of RNA three-dimensional structures, with predictions made by modeling groups before experimental structures are published.
  • - A significant set of predictions was made by 18 groups for 23 different RNA structures, including various elements like ribozymes and aptamers.
  • - The study highlights key challenges in RNA modeling, such as identifying helix pairs and ensuring proper stacking, and notes that some top-performing groups also excelled in a separate competition (CASP15).
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COVID-19 vaccines have successfully reduced severe disease and death after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Nonetheless, COVID-19 vaccines are variably effective in preventing transmission and symptomatic SARS-CoV-2 infection. Here, we evaluated the impact of mucosal or intramuscular vaccine immunization on airborne infection and transmission of SARS-CoV-2 in Syrian hamsters.

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Up to 25% of individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exhibit postacute cognitive sequelae. Although millions of cases of coronavirus disease 2019 (COVID-19)-mediated memory dysfunction are accumulating worldwide, the underlying mechanisms and how vaccination lowers risk are unknown. Interleukin-1 (IL-1), a key component of innate immune defense against SARS-CoV-2 infection, is elevated in the hippocampi of individuals with COVID-19.

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Unlabelled: The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with greater transmissibility or immune evasion properties has jeopardized the existing vaccine and antibody-based countermeasures. Here, we evaluated the efficacy of boosting pre-immune hamsters with protein nanoparticle vaccines (Novavax, Inc.) containing recombinant Prototype (Wuhan-1) or BA.

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Up to 25% of SARS-CoV-2 patients exhibit post-acute cognitive sequelae. Although millions of cases of COVID-19-mediated memory dysfunction are accumulating worldwide, the underlying mechanisms and how vaccination lowers risk are unknown. Interleukin-1, a key component of innate immune defense against SARS-CoV-2 infection, is elevated in the hippocampi of COVID-19 patients.

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The stem-loop II motif (s2m) is an RNA structural element that is found in the 3' untranslated region (UTR) of many RNA viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Though the motif was discovered over 25 years ago, its functional significance is unknown. In order to understand the importance of s2m, we created viruses with deletions or mutations of the s2m by reverse genetics and also evaluated a clinical isolate harboring a unique s2m deletion.

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Unlabelled: The stem-loop II motif (s2m) is a RNA structural element that is found in the 3' untranslated region (UTR) of many RNA viruses including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Though the motif was discovered over twenty-five years ago, its functional significance is unknown. In order to understand the importance of s2m, we created viruses with deletions or mutations of the s2m by reverse genetics and also evaluated a clinical isolate harboring a unique s2m deletion.

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Heartland and Bourbon viruses are pathogenic tick-borne viruses putatively transmitted by Amblyomma americanum, an abundant tick species in Missouri. To assess the prevalence of these viruses in ticks, we collected 2778 ticks from eight sampling sites at Tyson Research Center, an environmental field station within St. Louis County and close to the City of St.

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Unlabelled: COVID-19 emergency use authorizations and approvals for vaccines were achieved in record time. However, there remains a need to develop additional safe, effective, easy-to-produce, and inexpensive prevention to reduce the risk of acquiring SARS-CoV-2 infection. This need is due to difficulties in vaccine manufacturing and distribution, vaccine hesitancy, and, critically, the increased prevalence of SARS-CoV-2 variants with greater contagiousness or reduced sensitivity to immunity.

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Background: Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019, viral variants with greater transmissibility or immune-evasion properties have arisen, which could jeopardize recently deployed vaccine- and antibody-based countermeasures.

Methods: Here, we evaluated in mice and hamsters the efficacy of a pre-clinical version of the Moderna mRNA vaccine (mRNA-1273) and the Johnson & Johnson recombinant adenoviral-vectored vaccine (Ad26.COV2.

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Article Synopsis
  • The emergence of new SARS-CoV-2 variants threatens the effectiveness of immunity from previous infections or vaccinations.
  • To tackle this issue, the NIH launched the SARS-CoV-2 Assessment of Viral Evolution (SAVE) program for real-time assessment of variant risks that might impact transmission and vaccine efficacy.
  • The program focuses on gathering and analyzing data on emerging variants and their effects on immunity, using animal models, while also addressing future challenges in monitoring rapidly evolving viruses.
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  • The Omicron variant B.1.1.529 has raised concerns about its ability to evade vaccine protection and therapeutic antibodies.
  • Research using mice and hamsters revealed that B.1.1.529 caused less severe respiratory infections compared to previous SARS-CoV-2 variants, even though it binds strongly to mouse ACE2.
  • The findings indicate a milder disease response in rodents infected with B.1.1.529, which aligns with some early clinical observations in humans.
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Despite the development and deployment of antibody and vaccine countermeasures, rapidly-spreading SARS-CoV-2 variants with mutations at key antigenic sites in the spike protein jeopardize their efficacy. The recent emergence of B.1.

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The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein is the main target for neutralizing antibodies. These antibodies can be elicited through immunization or passively transferred as therapeutics in the form of convalescent-phase sera or monoclonal antibodies (MAbs). Potently neutralizing antibodies are expected to confer protection; however, it is unclear whether weakly neutralizing antibodies contribute to protection.

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With the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with increased transmissibility and potential resistance, antibodies and vaccines with broadly inhibitory activity are needed. Here, we developed a panel of neutralizing anti-SARS-CoV-2 monoclonal antibodies (mAbs) that bound the receptor binding domain of the spike protein at distinct epitopes and blocked virus attachment to its host receptor, human angiotensin converting enzyme-2 (hACE2). Although several potently neutralizing mAbs protected K18-hACE2 transgenic mice against infection caused by ancestral SARS-CoV-2 strains, others induced escape variants in vivo or lost neutralizing activity against emerging strains.

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Article Synopsis
  • * Analysis of monoclonal antibodies from mRNA vaccine-elicited B cells revealed that while most neutralized the original WA1/2020 D614G strain, their effectiveness varied against variants like B.1.617.2 and B.1.351.
  • * The monoclonal antibody 2C08 was particularly effective, reducing lung viral loads in hamsters and was found in a significant portion of individuals vaccinated or infected with SARS-CoV-2, indicating potential for wider application in combating variants.
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Rapidly emerging SARS-CoV-2 variants jeopardize antibody-based countermeasures. Although cell culture experiments have demonstrated a loss of potency of several anti-spike neutralizing antibodies against variant strains of SARS-CoV-2, the in vivo importance of these results remains uncertain. Here we report the in vitro and in vivo activity of a panel of monoclonal antibodies (mAbs), which correspond to many in advanced clinical development by Vir Biotechnology, AbbVie, AstraZeneca, Regeneron and Lilly, against SARS-CoV-2 variant viruses.

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Rapidly-emerging variants jeopardize antibody-based countermeasures against SARS-CoV-2. While recent cell culture experiments have demonstrated loss of potency of several anti-spike neutralizing antibodies against SARS-CoV-2 variant strains1-3, the in vivo significance of these results remains uncertain. Here, using a panel of monoclonal antibodies (mAbs) corresponding to many in advanced clinical development by Vir Biotechnology, AbbVie, AstraZeneca, Regeneron, and Lilly we report the impact on protection in animals against authentic SARS-CoV-2 variants including WA1/2020 strains, a B.

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Article Synopsis
  • The emergence of new SARS-CoV-2 variants that spread quickly poses a significant public health risk, especially since some are resistant to vaccines and natural infection antibodies.
  • Researchers discovered a human monoclonal antibody, known as 2C08, that is highly effective in neutralizing various SARS-CoV-2 variants and can reduce illness in tested hamsters.
  • The presence of similar B cell clones that produce 2C08-like antibodies in vaccinated individuals suggests that effective responses to these variants can be stimulated by existing COVID-19 vaccines.
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  • RNA-Puzzles is a collaboration aimed at enhancing how RNA 3D structures are predicted and involves predicting structures before crystallography results are published.
  • The study focuses on six RNA sequences, analyzing methods for comparing predicted models with crystal structures and highlights key issues like coaxial stacking, ligand binding, and areas needing improvement.
  • Findings suggest that accurately predicting coaxial stacking and tertiary contacts is crucial for RNA structure prediction, while simultaneous accurate predictions of structure and ligand binding remain challenging.
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Background: Sickle cell disease (SCD) affects 100,000 patients in the USA. However, no recent data was available for annual national trends in hospitalization rates, in-hospital mortality, hospital length of stay (LOS) and costs of SCD admissions due to its complications.

Methods: This study was conducted to study the trends of hospitalization rates, in-hospital mortality, LOS and hospital charges due to SCD-related complications in African American (AA) patients from 2004 to 2012 in the USA.

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Aim: The aim of the study was to compare chromogranin A (CgA) and stress levels before and after non-surgical periodontal therapy (NSPT).

Materials And Methods: A sample of 40 patients in the age range 25-60 years were included in the study and were divided into gingivitis (10 subjects), chronic periodontitis (CP) (15 patients) and aggressive periodontitis (AgP) (15 patients). The patients were asked to complete two sets of stress questionnaires, plaque index, gingival index, probing depth and clinical attachment levels (CAL) were recorded.

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Aim: Periodontitis and diabetes mellitus share a bidirectional relationship. Resistin is an adipocytokine shown to be associated with type 2 diabetes mellitus. Hence, the present study aims to estimate the effect of non-surgical periodontal therapy (NSPT) on GCF resistin levels in healthy individuals with gingivitis and well controlled diabetics with periodontitis, and correlate the same with HbA1c levels of the diabetic subjects.

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Shared Decision Making (SDM) is an essential component of recovery oriented treatment for clients with severe and persistent mental illnesses. SDM has been found to be effective in improving outcome of treatment of non-psychiatric ailments, and studies of SDM in community mental health settings are limited. We designed and implemented a low tech SDM program in a non-academic community mental health center and evaluated the outcome on decisional certainty and satisfaction with services.

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