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3.
ssrn; 2024.
Preprint em Inglês | PREPRINT-SSRN | ID: ppzbmed-10.2139.ssrn.4771235

Assuntos
COVID-19
5.
ssrn; 2024.
Preprint em Inglês | PREPRINT-SSRN | ID: ppzbmed-10.2139.ssrn.4774317

Assuntos
COVID-19
13.
preprints.org; 2024.
Preprint em Inglês | PREPRINT-PREPRINTS.ORG | ID: ppzbmed-10.20944.preprints202402.1366.v2

RESUMO

Background: Vaccine hesitancy was one of India's problems after the COVID-19 vaccine roll-out. Earlier studies carried out to understand people's perception of the vaccine were mainly based on online or offline community-based surveys. These studies do not help to understand the actions taken by people towards vaccination. Hence, this study has been designed to understand the exact behavior of people toward the vaccine. Methods: Age-wise, the population was sub-grouped into three groups, above 18 years, 12-14 years, and 15-18 years. The data analysis has been done using cumulative coverage of vaccines in the said age groups. Results: The study shows a substantial population has missed second and booster doses of vaccine at the state, regional, and national levels in all three age groups. Even for the states that have shown the smallest number of people who missed their dose, their number is in the thousands. Conclusion: Further research is needed to know, in total population, how many people have not even taken a single dose of vaccine. Policy-level efforts are needed to cover the entire population of the country for at least a single dose and vulnerable populations, for additional booster doses after primary doses.


Assuntos
COVID-19
14.
preprints.org; 2024.
Preprint em Inglês | PREPRINT-PREPRINTS.ORG | ID: ppzbmed-10.20944.preprints202403.1659.v1

RESUMO

The COVID-19 pandemic has shown varying effects on adolescents’ mental health, psychosocial functioning, risk behaviours, and victimisation. This study aims to examine the changes reported by a sample of Swedish adolescents (N=1607) at the end of the first year of the pandemic in relation to these factors. Data was collected with an electronic survey between September 2020 and February 2021, targeting upper-secondary high school students (aged 15-19 years). The results indicate a relatively low overall impact of the pandemic on Swedish upper-secondary school students, with notable gender differences. Compared to females, a higher percentage of male adolescents reported experiencing elevated levels of anxiety, depression, sleep disturbances, anger, and increased illicit drug use as consequences of the pandemic. In contrast, females demonstrated an increase in several salutogenic behaviours. Victimisation rates generally decreased during this period. These findings underscore the importance of heightened awareness among professionals within schools, social services, and healthcare settings regarding the distinct challenges encountered by a larger portion of male adolescents during the COVID-19 pandemic in Sweden.


Assuntos
Transtorno Depressivo , Transtornos do Sono-Vigília , Transtornos de Ansiedade , COVID-19
15.
preprints.org; 2024.
Preprint em Inglês | PREPRINT-PREPRINTS.ORG | ID: ppzbmed-10.20944.preprints202403.1661.v1

RESUMO

In this report we describe the case of a healthy, young, athletic woman who developed acute lymphoblastic leukaemia (ALL)/lymphoblastic lymphoma (LBL) after receiving the second dose of the Pfizer/BioNTech modified mRNA (modRNA) COVID-19 genetic vaccine (marketed as Comirnaty®). The first dose of the genetic vaccine did not appear to illicit any noticeable side effects, but within 24 hours of the second dose the patient suffered widespread and intensifying bone pain, fever, vomiting, and general malaise. Due to the persistence of the symptoms, the patient underwent a series of tests and examinations including a full laboratory workup, a consult with a clinical immunologist and rheumatologist, a Positron Emission Tomography (PET) imaging, as well as an osteomedullary biopsy. These together led to a definitive diagnosis of ALL. A time interval of 16 weeks from the second vaccination to the diagnosis of cancer was noted. Several similar cases with identical pathology which developed after the modRNA COVID-19 vaccination, are described in case reports in the scientific literature. The massive and indiscriminate use of genetic vaccines to fight COVID-19 is raising serious concerns about their safety and about the technology platform as a whole for this purpose. Growing evidence is accumulating regarding the biodistribution and persistence of the modRNA which can reach, thanks to the lipid nanoparticles, a multitude of tissues and organs of the body, including the bone marrow and other blood-forming organs and tissues. Moreover, there is evidence that the modRNA vaccines display a particular tropism for the bone marrow, influencing the immune system at multiple levels and being able to trigger not only autoimmune-based pathologies, but also neoplastic mechanisms. The aim of this article is to assess, on the basis of the available scientific literature, the risk of developing haematopoietic cancers after modRNA vaccination, and to investigate the potential genetic mechanisms involved in the pathogenesis of disease.


Assuntos
Neoplasias , Leucemia-Linfoma Linfoblástico de Células Precursoras , Vômito , Febre , COVID-19 , Dor , Doenças da Medula Óssea
16.
biorxiv; 2024.
Preprint em Inglês | bioRxiv | ID: ppzbmed-10.1101.2024.03.27.586931

RESUMO

Since the precursor frequency of naive T cells is extremely low, investigating the early steps of antigen-specific T cell activation is challenging. To overcome this detection problem, adoptive transfer of a cohort of T cells purified from T cell receptor (TCR) transgenic donors has been extensively used but is not readily available for emerging pathogens. Constructing TCR transgenic mice from T cell hybridomas is a labor-intensive and sometimes erratic process, since the best clones are selected based on antigen-induced CD69 upregulation or IL-2 production in vitro, and TCR chains are PCR-cloned into expression vectors. Here, we exploited the rapid advances in single cell sequencing and TCR repertoire analysis to select the best clones without hybridoma selection, and generated CORSET8 mice (CORona Spike Epitope specific CD8 T cell), carrying a TCR specific for the Spike protein of SARS-CoV-2. Implementing newly created DALI software for TCR repertoire analysis in single cell analysis enabled the rapid selection of the ideal responder CD8 T cell clone, based on antigen reactivity, proliferation and immunophenotype in vivo. In contrast, a traditional method based on hybridoma technology was unsuccessful. Identified TCR sequences were inserted as synthetic DNA into an expression vector and transgenic CORSET8 donor mice were created. After immunization with Spike/CpG-motifs, mRNA vaccination or SARS-CoV2 infection, CORSET8 T cells strongly proliferated and showed signs of T cell activation. Thus, a combination of TCR repertoire analysis and scRNA immunophenotyping allowed rapid selection of antigen-specific TCR sequences that can be used to generate TCR transgenic mice.


Assuntos
Síndrome Respiratória Aguda Grave
17.
biorxiv; 2024.
Preprint em Inglês | bioRxiv | ID: ppzbmed-10.1101.2024.03.26.586802

RESUMO

With the prevalence of sequentially-emerged sublineages including BA.1, BA.2 and BA.5, SARS-CoV-2 Omicron infection has transformed into a regional epidemic disease. As a sublineage of BA.5, the BA.5.2.48 outbreak and evolved into multi-subvariants in China without clearly established virological characteristics, especially the pathogenicity. Though reduced airborne transmission and pathogenicity of former Omicron sublineages have been revealed in animal models, the virological characteristics of BA.5.2.48 was unidentified. Here, we evaluated the in vitro and in vivo virological characteristics of two isolates of the prevalent BA.5.2.48 subvariant, DY.2 and DY.1.1 (a subvariant of DY.1). DY.2 replicates more efficiently than DY.1.1 in HelahACE2+ cells and Calu-3 cells. The A570S mutation (of DY.1) in a normal BA.5 spike protein (DY.2) leads to a 20% improvement in the hACE2 binding affinity, which is slightly reduced by a further K147E mutation (of DY.1.1). Compared to the normal BA.5 spike, the double-mutated protein demonstrates efficient cleavage and reduced fusogenicity. BA.5.2.48 demonstrated enhanced airborne transmission capacity in hamsters than BA.2. The pathogenicity of BA.5.2.48 is greater than BA.2, as revealed in K18-hACE2 rodents. Under immune selection pressure, DY.1.1 shows stronger fitness than DY.2 in hamster turbinates. Thus the outbreaking prevalent BA.5.2.48 multisubvariants exhibites divergent virological features.


Assuntos
Encefalite por Arbovirus , Convulsões
18.
biorxiv; 2024.
Preprint em Inglês | bioRxiv | ID: ppzbmed-10.1101.2024.03.27.584106

RESUMO

Nucleic acid amplification tests including reverse transcription-quantitative PCR (RT-qPCR) are used to detect RNA from Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the causative agent of the Coronavirus disease 2019 (COVID-19) pandemic. Standardized measurements of RNA can facilitate comparable performance of laboratory tests in the absence of existing reference measurement systems early on in a pandemic. Interlaboratory study CCQM-P199b 'SARS-CoV-2 RNA copy number quantification' was designed to test the fitness-for-purpose of developed candidate reference measurement procedures (RMPs) for SARS-CoV-2 genomic targets in purified RNA materials, and was conducted under the auspices of the Consultative Committee for Amount of Substance: Metrology in Chemistry and Biology (CCQM) to evaluate the measurement comparability of national metrology institutes (NMIs) and designated institutes (DIs), thereby supporting international standardization. Twenty-one laboratories participated in CCQM-P199b and were requested to report the RNA copy number concentration, expressed in number of copies per microliter, of the SARS-CoV-2 nucleocapsid (N) gene partial region (NC_045512.2: 28274-29239) and envelope (E) gene (NC_045512.2: 26245-26472) (optional measurement) in samples consisting of in vitro transcribed RNA or purified RNA from lentiviral constructs. Materials were provided in two categories: lower concentration (approximately 10 x 1 - 10 x 4/uL in aqueous solution containing human RNA background) and high concentration (approximately 10 x 9/uL in aqueous solution without any other RNA background). For the measurement of N gene concentration in the lower concentration study materials, the majority of laboratories (n = 17) used one-step reverse transcription-digital PCR (RT-dPCR), with three laboratories applying two-step RT-dPCR and one laboratory RT-qPCR. Sixteen laboratories submitted results for E gene concentration. Reproducibility (% CV or equivalent) for RT-dPCR ranged from 19 % to 31 %. Measurements of the high concentration study material by orthogonal methods (isotope dilution-mass spectrometry and single molecule flow cytometry) and a gravimetrically linked lower concentration material were in a good agreement, suggesting a lack of overall bias in RT-dPCR measurements. However methodological factors such as primer and probe (assay) sequences, RT-dPCR reagents and dPCR partition volume were found to be potential sources of interlaboratory variation which need to be controlled when applying this technique. This study demonstrates that the accuracy of RT-dPCR is fit-for-purpose as a RMP for viral RNA target quantification in purified RNA materials and highlights where metrological approaches such as the use of in vitro transcribed controls, orthogonal methods and measurement uncertainty evaluation can support standardization of molecular methods.


Assuntos
COVID-19 , Síndrome Respiratória Aguda Grave
19.
biorxiv; 2024.
Preprint em Inglês | bioRxiv | ID: ppzbmed-10.1101.2024.03.26.583354

RESUMO

Memory T cells are records of clonal expansion from prior immune exposures, such as infections, vaccines and chronic diseases like cancer. A subset of the receptors of these expanded T cells in a typical immune repertoire are highly public, i.e., present in many individuals exposed to the same exposure. For the most part, the exposures associated with these public T cells are unknown. To identify public T-cell receptor signatures of immune exposures, we mined the immunosequencing repertoires of tens of thousands of donors to define clusters of co-occurring T cells. We first built co-occurrence clusters of T cells responding to antigens presented by the same Human Leukocyte Antigen (HLA) and then combined those clusters across HLAs. Each cross-HLA cluster putatively represents the public T-cell signature of a single prevalent exposure. Using repertoires from donors with known serological status for 7 prevalent exposures (HSV-1, HSV-2, EBV, Parvovirus, Toxoplasma gondii, Cytomegalovirus and SARS CoV-2), we identified a single T-cell cluster strongly associated with each exposure and used it to construct a highly sensitive and specific diagnostic model for the exposure. These T-cell clusters constitute the public immune responses to prevalent exposures, 7 known and many others unknown. By learning the exposure associations for more T cell clusters, this approach could be used to derive a ledger of a person's past and present immune exposures.


Assuntos
Neoplasias , Toxoplasmose
20.
biorxiv; 2024.
Preprint em Inglês | bioRxiv | ID: ppzbmed-10.1101.2024.03.27.586885

RESUMO

SARS-CoV-2 infection leads to vastly divergent clinical outcomes ranging from asymptomatic infection to fatal disease. Co-morbidities, sex, age, host genetics and vaccine status are known to affect disease severity. Yet, how the inflammatory milieu of the lung at the time of SARS-CoV-2 exposure impacts the control of viral replication remains poorly understood. We demonstrate here that immune events in the mouse lung closely preceding SARS-CoV-2 infection significantly impact viral control and we identify key innate immune pathways required to limit viral replication. A diverse set of pulmonary inflammatory stimuli, including resolved antecedent respiratory infections with S. aureus or influenza, ongoing pulmonary M. tuberculosis infection, ovalbumin/alum-induced asthma or airway administration of defined TLR ligands and recombinant cytokines, all establish an antiviral state in the lung that restricts SARS-CoV-2 replication upon infection. In addition to antiviral type I interferons, the broadly inducible inflammatory cytokines TNF and IL-1 precondition the lung for enhanced viral control. Collectively, our work shows that SARS-CoV-2 may benefit from an immunologically quiescent lung microenvironment and suggests that heterogeneity in pulmonary inflammation that precedes or accompanies SARS-CoV-2 exposure may be a significant factor contributing to the population-wide variability in COVID-19 disease outcomes.


Assuntos
Deficiência de Proteína S , Tuberculose Pulmonar , Pneumonia , Asma , Síndrome Respiratória Aguda Grave , COVID-19 , Infecções Respiratórias
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