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Japanese green tea, an essential beverage in Japanese culture, is characterized by the initial steaming of freshly harvested leaves during production. This process efficiently inactivates endogenous enzymes such as polyphenol oxidases, resulting in the production of sencha, gyokuro, and matcha that preserves the vibrant green color of young leaves. Although genome sequences of several tea cultivars and germplasms have been published, no reference genome sequences are available for Japanese green tea cultivars. Here, we constructed a reference genome sequence of the cultivar 'Seimei', which is used to produce high-quality Japanese green tea. Using the PacBio HiFi and Hi-C technologies for chromosome-scale genome assembly, we obtained 15 chromosome sequences with a total genome size of 3.1 Gb and an N50 of 214.9 Mb. By analyzing the genomic diversity of 23 Japanese tea cultivars and lines, including the leading green tea cultivars 'Yabukita' and 'Saemidori', revealed several candidate genes that could be related to the characteristics of Japanese green tea. The reference genome of 'Seimei' and information on genomic diversity of Japanese green tea cultivars should provide crucial information for effective breeding of such cultivars in the future.
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Sjögren's syndrome (SS) is an autoimmune disorder characterized by oral dryness that is primarily attributed to tumor necrosis factor alpha (TNF-α)-mediated reduction in saliva production. In traditional Chinese medicine, goji berries are recognized for their hydrating effect and are considered suitable to address oral dryness associated with Yin deficiency. In the present study, we used goji berry juice (GBJ) to investigate the potential preventive effect of goji berries on oral dryness caused by SS. Pretreatment of human salivary gland cells with GBJ effectively prevented the decrease in aquaporin-5 (AQP-5) mRNA and protein levels induced by TNF-α. GBJ also inhibited histone H4 deacetylation and suppressed the generation of intracellular reactive oxygen species (ROS). Furthermore, GBJ pretreatment reserved mitochondrial membrane potential and suppressed the upregulation of Bax and caspase-3, indicating that GBJ exerted an antiapoptotic effect. These findings suggest that GBJ provides protection against TNF-α in human salivary gland cells and prevents the reduction of AQP-5 expression on the cell membrane. Altogether, these results highlight the potential role of GBJ in preventing oral dryness caused by SS.
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Lycium , Síndrome de Sjogren , Xerostomia , Humanos , Fator de Necrose Tumoral alfa/metabolismo , Lycium/metabolismo , Glândulas Salivares/metabolismo , Glândulas Salivares/patologia , Xerostomia/induzido quimicamente , Xerostomia/prevenção & controle , Xerostomia/complicações , Síndrome de Sjogren/complicações , Síndrome de Sjogren/metabolismo , Síndrome de Sjogren/patologia , Aquaporina 5/genéticaRESUMO
Research regarding the process of salivary gland development and elucidation of related mechanisms are considered essential for development of effective treatments for conditions associated with salivary disease. Various reports regarding the effects of bone morphogenetic protein (BMP)-2 on hard tissue cells have been presented, though few have examined those related to salivary gland formation. Using an organ culture system, the present study was conducted to investigate the function of BMP-2 in salivary gland formation. Salivary glands obtained from embryonic day 13.5 mice and treated with BMP-2 showed suppression of primordial cell differentiation and also gland formation in a concentration-dependent manner. Furthermore, gland formation inhibition was suppressed by concurrent treatment with dorsomorphin, an inhibitor of the Smad pathway. Expression levels of AQP5, a marker gene for acinar cells, and Prol1, an opiorphin expressed in the lacrimal gland, were decreased in salivary glands treated with BMP-2. The present findings indicate that suppression of salivary gland formation, especially acinar differentiation, is induced by BMP-2, a phenomenon considered to be related to the Smad pathway.
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The coronavirus disease 2019 (COVID-19) pandemic remains a global public health concern. The clinical course and risk of developing severe illness among patients with COVID-19 who are at low-risk of severe COVID-19 remain uncertain. This retrospective cohort study from an isolation facility for low-risk COVID-19 patients in Japan evaluated the potential risks for severe disease with hypoxia (SpO2 ≤ 93%) or experiencing prolonged isolation period longer than 14 days with persistent acute symptoms. The study was performed before the spread of the alpha variant in the country and before the start of a nationwide mass vaccination campaign against COVID-19. Among the 929 participants with reliable outcome data regarding the development of hypoxia, 63 (6.8%) developed severe disease with hypoxia during their stays at the facility. Higher age [adjusted odds ratio (aOR), 1.08; 95% confidence interval (CI), 1.06-1.10] and male sex (aOR, 4.70; 95% CI, 2.39-9.22) were associated with this outcome. As for the experience of prolonged isolation period, higher age (aOR, 1.02; 95% CI, 1.01-1.04), atopic diseases (aOR, 1.69, 95% CI, 1.09-2.64), presence of cough at onset (aOR, 1.64; 95% CI, 1.09-2.48), and prescription of oral antibiotics before positive test results for COVID-19 (aOR, 2.37; 95% CI, 1.33-4.22) were associated with this outcome. In summary, 5-10% of low-risk COVID-19 patients later develop hypoxia. Older age and male sex were associated with both the development of hypoxia and prolonged acute symptoms. The unnecessary prescription of antibiotics before COVID-19 diagnosis may prolong COVID-19 symptoms.
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COVID-19 , Humanos , Masculino , COVID-19/epidemiologia , SARS-CoV-2 , Estudos Retrospectivos , Teste para COVID-19 , HipóxiaRESUMO
A formerly unpublicized briarane diterpenoid, briastecholide M (1), and its established analogue, brianodin B (2), were purified from Briareum stechei, an octocoral collected from Okinawan waters. Using spectroscopic methods, the structure of 1 was established. Functional study showed that 1 can reducing the release of inducible nitric oxide synthase (iNOS) but enhancing cyclooxygenase-2 (COX-2) protein expression.
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Antozoários , Diterpenos , Animais , Antozoários/química , Antozoários/metabolismo , Diterpenos/farmacologia , Diterpenos/química , Óxido Nítrico Sintase Tipo II/metabolismo , Ciclo-Oxigenase 2/metabolismoRESUMO
This cross-sectional study examined nurses' eHealth literacy, health education experiences, and confidence in health education regarding online health information and explored their association. A self-administered questionnaire was distributed among 442 nurses in Japan from September 2020 to March 2021. The survey items were the Japanese version of the eHealth Literacy Scale, health education experiences and confidence in health education regarding online health information, and sociodemographic variables. The final analysis comprised 263 responses. Nurses' mean eHealth literacy was 21.89. Most nurses had never received questions regarding online health information in search (66.9%), evaluation (85.2%), and utilization (81.0%) from their patients. Further, most nurses lacked experience (84.0%-89.7%) and confidence (94.7%-97.3%) in health education regarding online health information. The factor associated with having health education experience regarding online health information was eHealth literacy (adjusted odds ratio, 1.08; 95% confidence interval, 1.02-1.15). Factors associated with having confidence in health education regarding online health information were eHealth literacy (adjusted odds ratio, 1.10; 95% confidence interval, 1.10-1.43) and having learning experiences regarding eHealth literacy (adjusted odds ratio, 7.36; 95% confidence interval, 2.06-26.39). Our findings suggest the importance of enhancing eHealth literacy among nurses and a proactive approach by nurses to improve patients' eHealth literacy.
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Letramento em Saúde , Telemedicina , Humanos , Estudos Transversais , Inquéritos e Questionários , Educação em Saúde , InternetRESUMO
Cdc42, a Rho family low molecular weight G protein, has important roles in various cell functions, including cytoskeletal rearrangement, cell adhesion and cell proliferation and differentiation. To investigate the involvement of Cdc42 in the activities of vascular endothelial cells, we generated Cdc42 conditional knockout mice in which Cdc42 was time -specifically deficient in vascular endothelial cells (Cdc42 âfl/fl; VE-Cad CreERT: Cdc42 cKO). When the Cdc42 gene was deleted after birth, Cdc42 cKO mice were smaller than the control mice, and died between postnatal day 8 (P8) and P10. Necropsy findings confirmed that these mice had various pathological aberrances in the vessels of most organs, such as blood flow congestion and blood cell invasion. Electron microscopic observations also revealed that capillary endothelial cells were detached from the basement membrane as well as phagocytosis of dead endothelial cells induced by macrophages. Moreover, vascular sprouting from aortic rings induced by VEGF-A was diminished in samples from the Cdc42 cKO mice because of an endothelial cell proliferation defect. These results suggest that Cdc42 in vascular endothelial cells has important roles in blood vessel formation after birth.
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Vasos Sanguíneos/crescimento & desenvolvimento , Células Endoteliais/fisiologia , Neovascularização Fisiológica/fisiologia , Proteína cdc42 de Ligação ao GTP/fisiologia , Animais , Camundongos KnockoutRESUMO
Myoepithelial (ME) cells in exocrine glands exhibit both epithelial and mesenchymal features, contributing to fluid secretion through contraction. However, the regulation mechanism of behind this unique phenotype in salivary glands remains unclear. We established a flow cytometry-based purification method using cell surface molecules, epithelial cell adhesion molecule (EpCAM) and alpha 6 integrin (CD49f), to characterize ME cells. EpCAM+CD49fhigh cells showed relatively high expression of ME cell-marker genes, such as alpha-smooth muscle actin (α-SMA). For lineage tracing and strict isolation, tdTomato+EpCAM+CD49fhigh-ME cells were obtained from myosin heavy chain 11 (Myh11) -CreERT2/tdTomato mice. Transcriptome analysis revealed that expression of genes involved in the epithelial-mesenchymal transition, including Snai2, were upregulated in the ME cell-enriched subset. Snai2 suppression in stable ME cells decreased α-SMA and increased Krt14 expression, suggesting that ME cell features may be controlled by the epithelial-mesenchymal balance regulated by Snai2. In contrast, ME cells showed reduced ME properties and expressed the ductal markers Krt18/19 under sphere culture conditions. Notch signaling was activated under sphere culture conditions; excessive activation of Notch signaling accelerated Krt18/19 expression, but reduced α-SMA and Snai2 expression, suggesting that the behavior of Snai2-expressing ME cells may be controlled by Notch signaling.
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Actinas , Cadeias Pesadas de Miosina , Camundongos , Animais , Integrina alfa6/metabolismo , Molécula de Adesão da Célula Epitelial/metabolismo , Actinas/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Células Epiteliais/metabolismo , Músculo Liso/metabolismo , Glândulas Salivares/metabolismo , Biomarcadores/metabolismoRESUMO
Salivary gland hypofunction due to radiation therapy for head and neck cancer or Sjögren syndrome may cause various oral diseases, which can lead to a decline in the quality of life. Cell therapy using salivary gland stem cells is a promising method for restoring hypofunction. Herein, we show that salivary gland-like cells can be induced from epithelial tissues that were transdifferentiated from mouse embryonic fibroblasts (MEFs). We introduced four genes, Dnp63a, Tfap2a, Grhl2, and Myc (PTMG) that are known to transdifferentiate fibroblasts into oral mucosa-like epithelium in vivo into MEFs. MEFs overexpressing these genes showed epithelial cell characteristics, such as cobblestone appearance and E-cadherin positivity, and formed oral epithelial-like tissue under air-liquid interface culture conditions. The epithelial sheet detached from the culture dish was infected with adenoviruses encoding Sox9 and Foxc1, which we previously identified as essential factors to induce salivary gland formation. The cells detached from the cell sheet formed spheres 10 days after infection and showed a branching morphology. The spheres expressed genes encoding basal/myoepithelial markers, cytokeratin 5, cytokeratin 14, acinar cell marker, aquaporin 5, and the myoepithelial marker α-smooth muscle actin. The dissociated cells of these primary spheres had the ability to form secondary spheres. Taken together, our results provide a new strategy for cell therapy of salivary glands and hold implications in treating patients with dry mouth.
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Células Acinares/metabolismo , Fibroblastos/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição SOX9/genética , Glândulas Salivares/metabolismo , Esferoides Celulares/metabolismo , Células Acinares/citologia , Adenoviridae/genética , Adenoviridae/metabolismo , Animais , Aquaporina 5/genética , Aquaporina 5/metabolismo , Biomarcadores/metabolismo , Caderinas/genética , Caderinas/metabolismo , Transdiferenciação Celular/genética , Terapia Baseada em Transplante de Células e Tecidos/métodos , Embrião de Mamíferos , Fibroblastos/citologia , Fatores de Transcrição Forkhead/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Queratina-14/genética , Queratina-14/metabolismo , Queratina-5/genética , Queratina-5/metabolismo , Camundongos , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição SOX9/metabolismo , Glândulas Salivares/citologia , Esferoides Celulares/citologia , Transativadores/genética , Transativadores/metabolismo , Fator de Transcrição AP-2/genética , Fator de Transcrição AP-2/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Although stem cell aging leads to a decline in tissue homeostasis and regenerative capacity, it remains unclear whether salivary gland stem cell function changes during this process. However, the salivary glands are gradually replaced by connective tissue during aging. Here, we show a decline in the stem cell ability of CD133-positive stem/progenitor cells in the salivary glands of aged mice. The CD133-positive cells were isolated from young, adult, and aged mice. The number of CD133-positive cells was significantly decreased in aged mice. They also showed a lower sphere formation capacity compared to young and adult mice. RNA sequencing revealed that CD133-positive cells in aged mice exhibited lower gene expression of several aging-related genes, including FoxO3a, than those in young and adult mice. Salivary gland cells infected with a recombinant lentivirus encoding the FoxO3a gene showed a reduction in oxidative stress induced by hydrogen peroxide compared with those infected with a control virus. Thus, FoxO3a may inhibit stem cell aging via oxidative stress.
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Envelhecimento/patologia , Senescência Celular/fisiologia , Glândulas Salivares/patologia , Células-Tronco/patologia , Animais , Linhagem Celular , Feminino , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Regeneração/fisiologia , Transplante de Células-Tronco/métodosRESUMO
Our ongoing interest in the relationships between chemical contents and genetic diversity of the nudibranch Phyllidiella pustulosa and related species found in Okinawa led to identification of a series of nitrogenous sesquiterpenoids. Among them, two new compounds 1 and 2 were elucidated after spectroscopic analysis. Their structures and cytotoxicity against three cell lines are described here.
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Gastrópodes , Sesquiterpenos , Animais , Estrutura Molecular , NitrogênioRESUMO
Two new furan derivatives, annulofurans A-B (1-2), together with six known compounds were isolated from Annulohypoxylon spougei fungus. The structures were determined based on NMR and mass spectrometry data. The absolute configurations of annulofurans A-B were determined by Electronic Circular Dichroism (ECD) experiment and comparisons with the experimental ECD spectra of synthesized stereoisomers. The evaluation of the effects on radish and ruzi grass radicle elongation by the isolated compounds showed that annulofuran A affected radicle elongation of ruzi grass. The known 2-hydroxyphenylacetic acid methyl ester (7) had significant effects against both radish and ruzi grass radicle elongation, which were comparable to the commercial herbicide, glyphosate.
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Furanos , Xylariales , Estrutura Molecular , Dicroísmo Circular , Furanos/farmacologia , Espectroscopia de Ressonância Magnética/métodosRESUMO
The Elongator complex, which is conserved in eukaryotes, has multiple roles in diverse organisms. In Arabidopsis thaliana, Elongator is shown to be involved in development, hormone action and environmental responses. However, except for Arabidopsis, our knowledge of its function is poor in plants. In this study, we initially carried out a genetic analysis to characterize a rice mutant with narrow and curled leaves, termed curled later1 (cur1). The cur1 mutant displayed a heteroblastic change, whereby the mutant leaf phenotype appeared specifically at a later adult phase of vegetative development. The shoot apical meristem (SAM) was small and the leaf initiation rate was low, suggesting that the activity of the SAM seemed to be partially reduced in cur1. We then revealed that CUR1 encodes a yeast ELP1-like protein, the largest subunit of Elongator. Furthermore, disruption of OsELP3 encoding the catalytic subunit of Elongator resulted in phenotypes similar to those of cur1, including the timing of the appearance of mutant phenotypes. Thus, Elongator activity seems to be specifically required for leaf development at the late vegetative phase. Transcriptome analysis showed that genes involved in protein quality control were highly upregulated in the cur1 shoot apex at the later vegetative phase, suggesting the restoration of impaired proteins probably produced by partial defects in translational control due to the loss of function of Elongator. The differences in the mutant phenotype and gene expression profile between CUR1 and its Arabidopsis ortholog suggest that Elongator has evolved to play a unique role in rice development.
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Meristema/fisiologia , Oryza/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Técnicas de Inativação de Genes , Histona Acetiltransferases/genética , Complexos Multiproteicos , Mutação , Oryza/crescimento & desenvolvimento , Fatores de Alongamento de Peptídeos/genética , Fenótipo , Folhas de Planta/citologia , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Subunidades Proteicas , Proteínas de Saccharomyces cerevisiae/genéticaRESUMO
BACKGROUND: Zinc is an essential micronutrient for maintaining biological activity. The level of zinc in the blood is known to decrease with age, especially in those over 75 years of age. In older adults patients with impaired functional status, aspiration pneumonia based on dysphagia often becomes problematic. However, the relationship between zinc deficiency and swallowing function has not been studied before. METHODS: A total of 52 older adults subjects (15 males and 37 females) living in a nursing home were enrolled for this study. At the time of enrollment, data of gender, age, body weight, serum zinc levels, serum albumin levels, and the time in a simple 2-step swallowing provocation test (S-SPT) were collected. In patients with serum zinc levels < 60 µg/dL, we initiated 2 months of oral zinc supplementation therapy with a 34 mg/day zinc load. Those who underwent zinc supplementation were re-evaluated after the treatment period and serum zinc levels and S-SPT time were measured. RESULTS: At the time of enrollment, serum zinc level was significantly correlated with serum albumin levels (Pearson's R = 0.58, p < 0.0001) and time in the S-SPT (Spearman's rho = - 0.32, p = 0.0219). Twenty-five of the 52 patients had zinc deficiency with a serum zinc level < 60 µg/dL. After 2 months of oral zinc supplementation, both serum zinc levels (p < 0.0001) and time in the S-SPT (p = 0.04) significantly improved. Meanwhile, serum albumin level (p = 0.48) or body weight (p = 0.07) did not significantly change following zinc supplementation. Zinc supplementation significantly improved swallowing function, especially in the older adults who had comorbid dysphagia and zinc deficiency. CONCLUSIONS: Zinc deficiency is associated with compromised swallowing function in older adults patients with impaired general functions. Oral zinc supplementation can alleviate dysphagia in older adults patients with zinc deficiency even though this is a retrospective study. Further study will be needed to confirm this positive effect.
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Transtornos de Deglutição , Pneumonia Aspirativa , Idoso , Deglutição , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/tratamento farmacológico , Feminino , Humanos , Masculino , Pneumonia Aspirativa/diagnóstico , Pneumonia Aspirativa/tratamento farmacológico , Estudos Retrospectivos , ZincoRESUMO
Chemical investigation of the octocoral Briareum stechei, collected in the Ie Island, Okinawa, Japan, resulted in the isolation of a new briarane-type diterpenoid, briastecholide A (1), as well as the previously reported metabolites, solenolide C (2) and briarenolide S (3). The structures of briaranes 1-3 were characterized through spectroscopic analysis, and the absolute configuration of 2 was corroborated by a single-crystal X-ray diffraction analysis. Briarane 3 exhibited bioactivity against the protein expression of inducible nitric oxide synthase (iNOS).
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Antozoários/química , Anti-Inflamatórios/isolamento & purificação , Diterpenos/isolamento & purificação , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Diterpenos/química , Diterpenos/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Japão , Camundongos , Óxido Nítrico Sintase Tipo II/genética , Células RAW 264.7 , Difração de Raios XRESUMO
Olfactory disorders are one of the characteristic symptoms of the coronavirus disease of 2019 (COVID-19), which causes infection and inflammation of the upper and lower respiratory tract. To our knowledge, there are no treatments for COVID-19-related olfactory disorder. Here, we report five olfactory disorder cases in COVID-19, treated using the Japanese traditional (Kampo) medicine, kakkontokasenkyushin'i. We treated five patients with mild COVID-19 at an isolation facility using Kampo medicine, depending on their symptoms. Patients with the olfactory disorder presented with a blocked nose, nasal discharge or taste impairment. Physical examination using Kampo medicine showed similar findings, such as a red tongue with red spots and sublingual vein congestion, which presented as blood stasis and inflammation; thus, we prescribed the Kampo medicine, kakkontokasenkyushin'i. After administration, the numeric rating scale scores of the smell impairment improved within 3 days from 9 to 3 in case 1, from 10 to 0 in case 2, from 9 to 0 in case 3, from 5 to 0 in case 4, and from 9 to 0 within 5 days in case 5. Following the treatment, other common cold symptoms were also alleviated. Kakkontokasenkyushin'i can be used for treating nasal congestion, rhinitis, and inflammation in the nasal mucosa. The olfactory disorder in COVID-19 has been reportedly associated with inflammation and congestion, especially in the olfactory bulb and olfactory cleft. Kakkontokasenkyushin'i may be one of the treatment alternatives for the olfactory disorder with rhinitis in patients with COVID-19.
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Tratamento Farmacológico da COVID-19 , Medicina Kampo/métodos , Transtornos do Olfato/tratamento farmacológico , Preparações de Plantas/uso terapêutico , Adolescente , Adulto , COVID-19/complicações , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Humanos , Japão , Masculino , Transtornos do Olfato/complicações , Transtornos do Olfato/virologia , Preparações de Plantas/química , Preparações de Plantas/farmacologia , Rinite/complicações , Rinite/tratamento farmacológico , Rinite/virologia , SARS-CoV-2/fisiologia , Olfato/efeitos dos fármacos , Resultado do Tratamento , Adulto JovemRESUMO
Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is the world's largest public health concern in 2021. This study evaluated the associations of the prevalence of airway symptoms among the tested individuals and data regarding the natural environmental factors with the weekly number of newly diagnosed COVID-19 patients in Sendai City (Nt). For the derivatives of the screening test results, data from individuals with a contact history who underwent nasopharyngeal swab reverse transcription-polymerase chain reaction (RT-PCR) testing between July 2020 and April 2021 (6,156 participants, including 550 test-positive patients) were used. The value of Nt correlated with the weekly RT-PCR test-positive rate after close contact, prevalence of cough symptoms in test-positive individuals or in test-negative individuals, lower air temperature, lower air humidity, and higher wind speed. The weekly test-positive rate correlated with lower air humidity and higher wind speed. In cross-correlation analyses, natural environmental factors correlated with the regional epidemic status on a scale of months, whereas the airway symptoms among non-COVID-19 population affected on a scale of weeks. When applying an autoregression model to the serial data of Nt, large-scale movements of people were suggested to be another factor to influence the local epidemics on a scale of days. In conclusion, the prevalence of cough symptoms in the local population, lower air humidity or higher wind speed, and large-scale movements of people in the locality would jointly influence the local epidemic status of COVID-19.
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COVID-19/epidemiologia , COVID-19/transmissão , Meio Ambiente , Epidemias , Adolescente , Adulto , COVID-19/diagnóstico , COVID-19/virologia , Criança , Busca de Comunicante , Feminino , Humanos , Japão/epidemiologia , Masculino , Prevalência , Análise de Regressão , SARS-CoV-2/fisiologia , Fatores de Tempo , Adulto JovemRESUMO
The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remains a global public health concern in 2021. However, the risk of attending schools during the pandemic remains unevaluated. This study estimated the secondary transmission rate at schools using the results of a real-time reverse transcription-polymerase chain reaction (RT-PCR) screening test performed between July 2020 and April 2021, before starting the nationwide mass vaccination. A total of 1,924 students (20 RT-PCR-positive; 1.0%) from 52 schools or preschools were evaluated, together with 1,379 non-adults (95 RT-PCR-positive; 6.9%) exposed to SARS-CoV-2 in non-school environments. Assuming that the infectious index cases were asymptomatic and the transmission at schools followed a Bernoulli process, we estimated the probability of transmission after each contact at school as approximately 0.005 (0.5% per contact) with the current infection prevention measures at schools in Japan (i.e., hand hygiene, physical distancing, wearing masks, and effective ventilation). Furthermore, assuming that all children are capable of carrying the infection, then contact between an index case and 20-30 students per day at schools would yield the expected value for secondary cases of ≥ 1.0, during the 10 days of the infectious period. In conclusion, with the current infection prevention measures at schools in Japan, secondary transmission at schools would occur in approximately every 200 contacts. When considering this rate, compliance with the current infection prevention measures at schools and early detection and quarantine of the index cases would be effective in preventing the spread of COVID-19 at schools.
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COVID-19/transmissão , Quarentena , Estudantes , Adolescente , COVID-19/epidemiologia , COVID-19/prevenção & controle , Criança , Pré-Escolar , Feminino , Humanos , Japão/epidemiologia , Masculino , SARS-CoV-2 , Instituições AcadêmicasRESUMO
In response to the COVID-19 pandemic caused by SARS-CoV-2 in 2020, we conducted drive-through nasopharyngeal swab testing for COVID-19 in Sendai city, Japan, since April 2020. All tested individuals were judged in advance by public health centers for the necessity of undergoing the test with possible contact history and/or symptoms suggestive of COVID-19. In this study, to identify the predictors of SARS-CoV-2 test positivity for more efficient and evidenced selection of suspected individuals, we enrolled 3,540 consecutive individuals, tested in the first 7 months of the testing program, with data regarding to the history of close contact with COVID-19 patients, including those involved in cluster outbreaks. This cohort included 284 foreign students (257 males and 27 females) from a vocational school involved in the largest cluster outbreak in the area. Close contact history was present in 952 (26.9%) of the participants. The reverse transcription-polymerase chain reaction (RT-PCR) test results showed that 164 participants (4.6%) were positive and 3,376 participants (95.4%) were negative for the SARS-CoV-2 nucleocapsid gene (N2). In the univariate and multivariate analyses, history of close contact with COVID-19 patients, higher age, cough symptoms, and non-native ethnicity were predictors for SARS-CoV-2 test positivity. However, the significance of age and foreign nationality disappeared or declined upon excluding the foreign students from the aforementioned largest cluster outbreak. In conclusion, a history of close contact with COVID-19 patients and the presence of cough symptoms are significant predictors of SARS-CoV-2 test positivity.
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Teste para COVID-19/métodos , COVID-19/diagnóstico , Unidades de Diagnóstico Rápido , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Manejo de Espécimes/métodos , Adulto , Surtos de Doenças , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Desenvolvimento de Programas , Saúde Pública , SARS-CoV-2/genética , Adulto JovemRESUMO
Polybrominated diphenyl ether (PBDE) compounds, derived from marine organisms, originate from symbiosis between marine sponges and cyanobacteria or bacteria. PBDEs have broad biological spectra; therefore, we analyzed structure and activity relationships of PBDEs to determine their potential as anticancer or antibacterial lead structures, through reactions and computational studies. Six known PBDEs (1-6) were isolated from the sponge, Lamellodysdiea herbacea; 13C NMR data for compound 6 are reported for the first time and their assignments are confirmed by their theoretical 13C NMR chemical shifts (RMSE < 4.0 ppm). Methylation and acetylation of 1 (2, 3, 4, 5-tetrabromo-6-(3', 5'-dibromo-2'-hydroxyphenoxy) phenol) at the phenol functional group gave seven molecules (7-13), of which 10, 12, and 13 were new. New crystal structures for 8 and 9 are also reported. Debromination carried out on 1 produced nine compounds (1, 2, 14, 16-18, 20, 23, and 26) of which 18 was new. Debromination product 16 showed a significant IC50 8.65 ± 1.11; 8.11 ± 1.43 µM against human embryonic kidney (HEK293T) cells. Compounds 1 and 16 exhibited antibacterial activity against Gram-positive Staphylococcus aureus and Gram-negative Klebsiella pneumoniae with MID 0.078 µg/disk. The number of four bromine atoms and two phenol functional groups are important for antibacterial activity (S. aureus and K. pneumoniae) and cytotoxicity (HEK293T). The result was supported by analysis of frontier molecular orbitals (FMOs). We also propose possible products of acetylation and debromination using analysis of FMOs and electrostatic charges and we confirm the experimental result.