Antibody-dependent enhancement (ADE) is a phenomenon in which antibodies enhance subsequent viral infections rather than preventing them. Sub-optimal levels of neutralizing antibodies in individuals infected with dengue virus are known to be associated with severe disease upon reinfection with a different dengue virus serotype. For Severe Acute Respiratory Syndrome Coronavirus type-2 infection, three types of ADE have been proposed: (1) Fc receptor-dependent ADE of infection in cells expressing Fc receptors, such as macrophages by anti-spike antibodies, (2) Fc receptor-independent ADE of infection in epithelial cells by anti-spike antibodies, and (3) Fc receptor-dependent ADE of cytokine production in cells expressing Fc receptors, such as macrophages by anti-nucleocapsid antibodies.
View Article and Find Full Text PDFThe pluripotent stem cell (PSC)-derived human primordial germ cell-like cells (PGCLCs) are a cell culture-derived surrogate model of embryonic primordial germ cells. Upon differentiation of PSCs to PGCLCs, multiple loci of HML-2, the hominoid-specific human endogenous retrovirus (HERV), are strongly activated, which is necessary for PSC differentiation to PGCLCs. In PSCs, strongly activated loci of HERV-H family HERVs create chromatin contacts, which are required for the pluripotency.
View Article and Find Full Text PDFSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and vaccination elicit both T cell and B cell immune responses in immunocompetent individuals. However, the mechanisms underlying the antiviral effects mediated by CD4 T cells are not fully understood. In this study, we analyzed the culture supernatant (SN) from polyclonally stimulated human CD4 T cells as a model for soluble mediators derived from SARS-CoV-2-stimulated CD4 T cells.
View Article and Find Full Text PDFThe number of dengue cases has increased dramatically in recent years. In Latin America, the number of cases and deaths in 2023 was the highest ever recorded. We report on a patient who had been infected with dengue virus during his stay in Costa Rica in September 2023, and developed the disease after returning to Japan.
View Article and Find Full Text PDFDengue virus (DENV) is the causative agent of dengue. Although most infected individuals are asymptomatic or present with only mild symptoms, severe manifestations could potentially devastate human populations in tropical and subtropical regions. In hyperendemic regions such as South Asia and Southeast Asia (SEA), all four DENV serotypes (DENV-1, DENV-2, DENV-3, and DENV-4) have been prevalent for several decades.
View Article and Find Full Text PDFAn model of human meiosis would accelerate research into this important reproductive process and development of therapies for infertility. We have developed a method to induce meiosis starting from male or female human pluripotent stem cells. We demonstrate that DNMT1 inhibition, retinoid signaling activation, and overexpression of regulatory factors (anti-apoptotic BCL2, and pro-meiotic HOXB5, BOLL, or MEIOC) rapidly activates meiosis, with leptonema beginning at 6 days, zygonema at 9 days, and pachynema at 12 days.
View Article and Find Full Text PDFDespite high vaccination rates globally, countries are still grappling with new COVID infections, and patients diagnosed as mild dying at home during outpatient treatment. Hence, this study aim to identify, then validate, biomarkers that could predict if newly infected COVID-19 patients would subsequently require hospitalization or could recover safely with medication as outpatients. Serum cytokine/chemokine data from 129 COVID-19 patients within 7 days after the onset of symptoms in Bangladesh were used as training data.
View Article and Find Full Text PDFSupraglottic airway devices such as laryngeal masks and i-gels are useful for airway management. The i-gel is a relatively new device that replaces the air-inflated cuff of the laryngeal mask with a gel-filled cuff. It remains unclear which device is more effective for neonatal resuscitation.
View Article and Find Full Text PDFBackground And Objectives: In May 2022, the United Kingdom reported the first case of chained transmission of the monkeypox (mpox) virus without any known epidemiological links to west or central Africa. The monthly number of mpox patients currently has passed a peak and is declining globally, and infected patients include both non-vaccinated and vaccinated individuals. Herein, the virus-neutralizing (VN) activity against vaccinia viruses, which are considered to cross-react with the mpox virus, in the intravenous immunoglobulin (IVIG) lots derived from donors, including vaccinated Japanese populations, was evaluated to clarify the status of the Japanese blood donor population.
View Article and Find Full Text PDFWe investigated the molecular epidemiology of human norovirus (HuNoV) in all age groups using samples from April 2019 to March 2023, before and after the COVID-19 countermeasures were implemented. GII.2[P16] and GII.
View Article and Find Full Text PDFBurgeoning evidence demonstrates that effects of environmental exposures can be transmitted to subsequent generations through the germline without DNA mutations. This phenomenon remains controversial because underlying mechanisms have not been identified. Therefore, understanding how effects of environmental exposures are transmitted to unexposed generations without DNA mutations is a fundamental unanswered question in biology.
View Article and Find Full Text PDFCoronavirus disease 2019 (COVID-19) is a respiratory tract infection caused by severe acute respiratory syndrome coronavirus 2 that can have detrimental effects on multiple organs and accelerate patient mortality. This study, which encompassed 130 confirmed COVID-19 patients who were assessed at three different time points (i.e.
View Article and Find Full Text PDFLactic acid bacteria (LAB) were screened from (red sea bass), and their antimicrobial activities were evaluated against two species isolated from the , namely, (AV) and (AJ). Three LAB isolates, MU8 (EF_8), MU2 (EFL_2), and MU9 (EFL_9), were found to inhibit both AV and AJ; however, their cell-free supernatant (CFS) did not do so. Interestingly, bacteriocin-like substances (BLS) induced by cocultures of EF_8 with AV exhibited the highest antimicrobial activity against both sp.
View Article and Find Full Text PDFAccumulating evidence has demonstrated the presence of intertissue-communication regulating systemic aging, but the underlying molecular network has not been fully explored. We and others previously showed that two basic helix-loop-helix transcription factors, MML-1 and HLH-30, are required for lifespan extension in several longevity paradigms, including germlineless . However, it is unknown what tissues these factors target to promote longevity.
View Article and Find Full Text PDFWe present an all-polarization-maintaining mode-locked fiber laser based on a nonlinear amplifying loop mirror utilizing a 3 × 3 coupler. A pump laser diode placed outside the cavity pumps both the oscillator and fiber amplifier. This laser configuration effectively utilizes all ports of the coupler, making the laser compact and low-cost, and has great potential as a seed laser for ultrashort pulse lasers.
View Article and Find Full Text PDFMethods Mol Biol
July 2023
Primordial germ cells (PGCs) are the earliest form of mammalian germ lineage. In humans, PGCs are present during a very early and limited window in development, limiting the ability to study fundamental developmental steps in human reproductive biology. However, recent advancements in generating in-vitro models of gametogenesis have allowed the field to generate human primordial germ cell-like cells (hPGCLCs).
View Article and Find Full Text PDFDengue virus (DENV), which has circulated in Vietnam for several decades, has multiple serotypes and genotypes. A 2019 dengue outbreak resulted in a larger number of cases than any other outbreak. We conducted a molecular characterization using samples collected in 2019-2020 from dengue patients in Hanoi and nearby cities located in northern Vietnam.
View Article and Find Full Text PDFPeople are widely exposed to polycyclic aromatic hydrocarbons, like benzo[a]pyrene (BaP). Prior studies showed that prenatal exposure to BaP depletes germ cells in ovaries, causing earlier onset of ovarian senescence post-natally; developing testes were affected at higher doses than ovaries. Our primary objective was to determine if prenatal BaP exposure results in transgenerational effects on ovaries and testes.
View Article and Find Full Text PDFDengue virus (DENV) infections have unpredictable clinical outcomes, ranging from asymptomatic or minor febrile illness to severe and fatal disease. The severity of dengue infection is at least partly related to the replacement of circulating DENV serotypes and/or genotypes. To describe clinical profiles of patients and the viral sequence diversity corresponding to non-severe and severe cases, we collected patient samples from 2018 to 2022 at Evercare Hospital Dhaka, Bangladesh.
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