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Hsp90 is an essential chaperone that guards proteome integrity and amounts to 2% of cellular protein. We now find that Hsp90 also has the ability to directly interact with and deform membranes via an evolutionarily conserved amphipathic helix. Using a new cell-free system and in vivo measurements, we show this amphipathic helix allows exosome release by promoting the fusion of multivesicular bodies (MVBs) with the plasma membrane. We dissect the relationship between Hsp90 conformation and membrane-deforming function and show that mutations and drugs that stabilize the open Hsp90 dimer expose the helix and allow MVB fusion, while these effects are blocked by the closed state. Hence, we structurally separated the Hsp90 membrane-deforming function from its well-characterized chaperone activity, and we show that this previously unrecognized function is required for exosome release.
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Membrana Celular/metabolismo , Exossomos/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Animais , Sistema Livre de Células/metabolismo , Drosophila/metabolismo , Feminino , Masculino , Chaperonas Moleculares/metabolismo , Corpos Multivesiculares/metabolismo , Ligação Proteica/fisiologia , Conformação ProteicaRESUMO
The objective of this study is to assess the prevalence of antibiotic-resistant genes (ARGs) in the intestines of infants and the factors affecting their distribution. Breast milk and infant stool samples were collected from nine full-term, healthy mother-infant pairs. The bacterial distribution and various types of ARGs present in the samples were analyzed using metagenomic next-generation sequencing. Over a period spanning from 2 to 240 d after birth, a total of 273 types of ARGs were identified in both infant feces and breast milk, exhibiting a trend of increasing prevalence over time. High concentrations of representative ARG populations were identified in the intestines of infants, especially at 12-15 d after birth. These populations included APH3-Ib, tetW/N/W, mphA, and Haemophilus influenzae PBP3, and multiple ARG Escherichia coli soxS that were resistant to common clinically used aminoglycoside, tetracycline, macrolide, and beta-lactam antibiotics. Gammaproteobacteria and Bacilli, especially Enterococcus, Staphylococcus, Acinetobacter, Streptococcus, and Escherichia were among the identified ARG carriers. Maternal age and body mass index (present and before pregnancy), infant sex, maternal consumption of probiotic yogurt during pregnancy, and lactation might be substantial factors influencing the occurrence of ARG-carrying bacteria and ARG distribution in the infant feces. These results indicate that environmental factors may influence the distribution of ARG-carrying bacteria and ARGs themselves in infants during early life. Providing appropriate recommendations regarding maternal age, body mass index during pregnancy, and use of probiotic products could potentially mitigate the transmission of antibiotic-resistant microbiota and ARGs, thereby diminishing the risk of antibiotic-resistant infections and safeguarding children's health.
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Antibacterianos , Fezes , Leite Humano , Humanos , Feminino , Fezes/microbiologia , Antibacterianos/farmacologia , Leite Humano/microbiologia , Lactente , Recém-Nascido , Intestinos/microbiologia , Masculino , Farmacorresistência Bacteriana/genética , Genes Bacterianos , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/efeitos dos fármacos , Bactérias/genética , Bactérias/efeitos dos fármacos , Resistência Microbiana a Medicamentos/genéticaRESUMO
MAIN CONCLUSION: CsNAC086 was found to promote the expression of CsFLS, thus promoting the accumulation of flavonols in Camellia sinensis. Flavonols, the main flavonoids in tea plants, play an important role in the taste and quality of tea. In this study, a NAC TF gene CsNAC086 was isolated from tea plants and confirmed its regulatory role in the expression of flavonol synthase which is a key gene involved in the biosynthesis of flavonols in tea plant. Yeast transcription-activity assays showed that CsNAC086 has self-activation activity. The transcriptional activator domain of CsNAC086 is located in the non-conserved C-terminal region (positions 171-550), while the conserved NAC domain (positions 1-170) does not have self-activation activity. Silencing the CsNAC086 gene using antisense oligonucleotides significantly decreased the expression of CsFLS. As a result, the concentration of flavonols decreased significantly. In overexpressing CsNAC086 tobacco leaves, the expression of NtFLS was significantly increased. Compared with wild-type tobacco, the flavonols concentration increased. Yeast one-hybrid assays showed CsNAC086 did not directly regulate the gene expression of CsFLS. These findings indicate that CsNAC086 plays a role in regulating flavonols biosynthesis in tea plants, which has important implications for selecting and breeding of high-flavonols-concentration containing tea-plant cultivars.
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Camellia sinensis , Flavonóis , Regulação da Expressão Gênica de Plantas , Nicotiana , Proteínas de Plantas , Camellia sinensis/genética , Camellia sinensis/metabolismo , Flavonóis/biossíntese , Flavonóis/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Oxirredutases/genética , Oxirredutases/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/genética , Plantas Geneticamente ModificadasRESUMO
Recently, a significant amount of attention has been attracted toward a third classification of magnetism, altermagnetism, due to the unique physical properties of altermagnetic materials, which are compensated collinear antiferromagnets that host time-reversal symmetry-breaking phenomena like a ferromagnet. In an altermagnetic material, through the nonrelativistic altermagnetic spin-splitting effect (ASSE), a transverse spin current is generated upon charge current injection. However, it is very challenging to experimentally establish the ASSE since it is inevitably mixed with the spin Hall effect due to the relativistic spin-orbit coupling of the material. Additionally, the dependence on the hard-to-probe and hard-to-control Néel vectors makes it even more difficult to observe and establish the ASSE. In this Letter, we utilize the thermal spin injection from the ferrimagnetic insulator yttrium iron garnet and detect an inverse altermagnetic spin-splitting effect (IASSE) in the high-quality epitaxial altermagnetic RuO_{2} thin films. We observe an opposite sign for the spin-to-charge conversion through the IASSE compared to the inverse spin Hall effect (ISHE). The efficiency of the IASSE is approximately 70% of the ISHE in RuO_{2}. Moreover, we demonstrate that the ASSE or IASSE effect is observable only when the Néel vectors are well aligned. By modifying the Néel vector domains via RuO_{2} crystallinity, we study the ASSE or IASSE unequivocally and quantitatively. Our Letter provides significant insight into the spin-splitting effect in altermagnetic materials.
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A microdeletion of approximately 2.4 Mb at the 8p23 terminal region has been identified in a Taiwanese autistic boy. Among the products transcribed/translated from genes mapped in this region, the reduction of DLGAP2, a postsynaptic scaffold protein, might be involved in the pathogenesis of autism spectrum disorder (ASD). DLGAP2 protein was detected in the hippocampus yet abolished in homozygous Dlgap2 knockout (Dlgap2 KO) mice. In this study, we characterized the hippocampal phenotypes in Dlgap2 mutant mice. Dlgap2 KO mice exhibited impaired spatial memory, indicating poor hippocampal function in the absence of DLGAP2. Aberrant expressions of postsynaptic proteins, including PSD95, SHANK3, HOMER1, GluN2A, GluR2, mGluR1, mGluR5, ßCAMKII, ERK1/2, ARC, BDNF, were noticed in Dlgap2 mutant mice. Further, the spine density was increased in Dlgap2 KO mice, while the ratio of mushroom-type spines was decreased. We also observed a thinner postsynaptic density thickness in Dlgap2 KO mice at the ultrastructural level. These structural changes found in the hippocampus of Dlgap2 KO mice might be linked to impaired hippocampus-related cognitive functions such as spatial memory. Mice with Dlgap2 deficiency, showing signs of intellectual disability, a common co-occurring condition in patients with ASD, could be a promising animal model which may advance our understanding of ASD.
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Transtorno do Espectro Autista , Animais , Camundongos , Espinhas Dendríticas/metabolismo , Hipocampo/metabolismo , Transtornos da Memória , Camundongos Knockout , Proteínas dos Microfilamentos/metabolismo , Modelos Genéticos , Proteínas do Tecido Nervoso/metabolismo , Memória Espacial , Coluna Vertebral/metabolismo , Sinapses/metabolismoRESUMO
OBJECTIVE: This population-based study explored emergency room visits (ERVs) from all-causes, circulatory and respiratory diseases among different occupational groups in Taiwan associated with ambient average temperature. METHOD: Daily area-age-sex specific ERVs records were obtained from the Taiwan's Ministry of Health and Welfare from 2009 to 2018. Distributed lag-nonlinear model (DLNM) was used to estimate the exposure-response relationships between daily average temperature and ERVs for all-causes, circulatory and respiratory diseases by occupational groups. Random-effects meta-analysis was used to pool the overall cumulative relative risk (RR) and 95% confidence interval (CI). RESULTS: The exposure-response curves showed ERVs of all-cause and respiratory diseases increased with rising temperature across all occupational groups. These effects were consistently stronger among younger (20-64 years old) and outdoor workers. In contrast, ERVs risk from circulatory diseases increased significantly during cold snaps, with a substantially higher risk for female workers. Interestingly, female workers, regardless of indoor or outdoor work, consistently showed a higher risk of respiratory ERVs during hot weather compared to males. Younger workers (20-64 years old) exhibited a higher risk of ERVs, likely due to job profiles with greater exposure to extreme temperatures. Notably, the highest risk of all-causes ERVs was observed in outdoor male laborers (union members), followed by farmers and private employees, with the lowest risk among indoor workers. Conversely, female indoor workers and female farmers faced the highest risk of respiratory ERVs. Again, female farmers with consistent outdoor exposure had the highest risk of circulatory ERVs during cold conditions. CONCLUSION: Our findings highlighted the complexity of temperature-related health risks associated with different occupational contexts. The population-level insights into vulnerable occupational groups could provide valuable comprehension for policymakers and healthcare practitioners.
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AIMS: While certain drug-use indicators are known to be associated with clinical outcomes, the relationship is unclear for some highly prevalent conditions in in patients aged ≥65 years. We examine correlations between 3 drug-use indicators and postdischarge healthcare services use by older patients according to the presence of dementia, advanced age and frailty. METHODS: This retrospective cohort study analysed data collected from hospital electronic health records between April and December 2017. Potentially inappropriate medications (PIMs) and anticholinergic burden were assessed using the 2015 Beers Criteria and anticholinergic cognitive burden scale (ACBS) score. Minor and major polypharmacy were defined as the use of 5-9 and ≥10 drugs, respectively. Outcomes were set as emergency room revisits and readmissions at 1, 3 and 6 months postdischarge. The correlation between drug-use indicators and outcomes was analysed by multivariable logistic regression. RESULTS: The final cohort included 3061 patients for the analysis, and 2930, 2671 and 2560 patients were followed up to 1, 3 and 6 months after discharge. After controlling for confounders, all 3 drug-use indicators were significantly associated with readmission and emergency room revisits except for the relationship between PIMs and readmission within 6 months. These associations were significantly observed among patients without dementia, aged >80 years and with frailty. CONCLUSION: PIMs, polypharmacy and anticholinergic burden are common at discharge and correlate with future use of healthcare services. In older patients, the absence of dementia, advanced age and frailty should be given extra consideration with regard to medication safety.
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Demência , Fragilidade , Humanos , Idoso , Lista de Medicamentos Potencialmente Inapropriados , Alta do Paciente , Readmissão do Paciente , Prescrição Inadequada , Estudos Retrospectivos , Assistência ao Convalescente , Fragilidade/tratamento farmacológico , Polimedicação , Antagonistas Colinérgicos/uso terapêutico , Hospitais , Demência/tratamento farmacológico , Serviço Hospitalar de EmergênciaRESUMO
BACKGROUND: This study investigated associations between climate variables (average temperature and cumulative rainfall), and El Niño Southern Oscillation (ENSO) and dengue-like-illness (DLI) incidence in two provinces (Western and Guadalcanal Provinces) in Solomon Islands (SI). METHODS: Weekly DLI and meteorological data were obtained from the Ministry of Health and Medical Services SI and the Ministry of Environment, Climate Change, Disaster Management and Meteorology from 2015 to 2018, respectively. We used negative binomial generalized estimating equations to assess the effects of climate variables up to a lag of 2 months and ENSO on DLI incidence in SI. RESULTS: We captured an upsurge in DLI trend between August 2016 and April 2017. We found the effects of average temperature on DLI in Guadalcanal Province at lag of one month (IRR: 2.186, 95% CI: 1.094-4.368). Rainfall had minor but consistent effect in all provinces. La Niña associated with increased DLI risks in Guadalcanal Province (IRR: 4.537, 95% CI: 2.042-10.083), whereas El Niño associated with risk reduction ranging from 72.8% to 76.7% in both provinces. CONCLUSIONS: Owing to the effects of climate variability and ENSO on DLI, defining suitable and sustainable measures to control dengue transmission and enhancing community resilience against climate change in low- and middle-developed countries are important.
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Dengue , El Niño Oscilação Sul , Humanos , Temperatura , Incidência , Melanesia/epidemiologia , Dengue/epidemiologiaRESUMO
PURPOSE: While the gustatory pathway of animals has been well-researched, that of humans is still a mystery. Several theories have been established, and some earlier reports hypothesized the relation to laterality. However, some cases could not be fully explained by the laterality theory (1). To clarify the gustatory pathway, we reported a case with bilateral hypogeusia after right thalamic infarction. CASE: This 55-year-old, right-handed man suffered from sudden decreased sensitivity of taste. He was unable to differentiate sweetness and saltiness at bilateral anterior parts of tongue. Additionally, there was numbness at the upper palate and the lips. Neurological examination revealed decreased taste sense at both sides of his anterior tongue and decreased pin-prick sensation of the left part of his lips. Brain magnetic resonance imaging (MRI) revealed acute ischemic stroke at the right ventral posteromedial nucleus (VPM). Thus, single antiplatelet therapy was administered. Two weeks later, the symptoms improved significantly and completely recovered without sequelae. CONCLUSION: The exact gustatory pathway in humans remains uncertain nowadays. First, there were few reports about dysgeusia, which might be related to clinical neglect of taste deficits. Second, our knowledge of the human gustatory pathway depends solely on sporadic cases of taste-involved brain lesions. We reported a case of bilateral hypogeusia after right thalamic infarction. This finding indicates that, although there might be laterality of gustatory fibers to the left hemisphere, anatomical variations may exist in the human gustatory system. More research is needed to elucidate the understanding of the gustatory pathway in humans.
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Ageusia , AVC Isquêmico , Acidente Vascular Cerebral Lacunar , Animais , Masculino , Humanos , Pessoa de Meia-Idade , Ageusia/etiologia , Tálamo/diagnóstico por imagem , Núcleos Ventrais do Tálamo , Infarto Cerebral/complicações , Infarto Cerebral/diagnóstico por imagemRESUMO
BACKGROUND: The need is growing to create medical big data based on the electronic health records collected from different hospitals. Errors for sure occur and how to correct them should be explored. METHODS: Electronic health records of 9,197,817 patients and 53,081,148 visits, totaling about 500 million records for 2006-2016, were transmitted from eight hospitals into an integrated database. We randomly selected 10% of patients, accumulated the primary keys for their tabulated data, and compared the key numbers in the transmitted data with those of the raw data. Errors were identified based on statistical testing and clinical reasoning. RESULTS: Data were recorded in 1573 tables. Among these, 58 (3.7%) had different key numbers, with the maximum of 16.34/1000. Statistical differences (P < 0.05) were found in 34 (58.6%), of which 15 were caused by changes in diagnostic codes, wrong accounts, or modified orders. For the rest, the differences were related to accumulation of hospital visits over time. In the remaining 24 tables (41.4%) without significant differences, three were revised because of incorrect computer programming or wrong accounts. For the rest, the programming was correct and absolute differences were negligible. The applicability was confirmed using the data of 2,730,883 patients and 15,647,468 patient-visits transmitted during 2017-2018, in which 10 (3.5%) tables were corrected. CONCLUSION: Significant magnitude of inconsistent data does exist during the transmission of big data from diverse sources. Systematic validation is essential. Comparing the number of data tabulated using the primary keys allow us to rapidly identify and correct these scattered errors.
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Big Data , Pesquisa Biomédica , Bases de Dados Factuais , Registros Eletrônicos de Saúde , Humanos , Sistemas Multi-InstitucionaisRESUMO
State-of-charge (SOC) is a relative quantity that describes the ratio of the remaining capacity to the present maximum available capacity. Accurate SOC estimation is essential for a battery-management system. In addition to informing the user of the expected usage until the next recharge, it is crucial for improving the utilization efficiency and service life of the battery. This study focuses on applying deep-learning techniques, and specifically convolutional residual networks, to estimate the SOC of lithium-ion batteries. By stacking the values of multiple measurable variables taken at many time instants as the model inputs, the process information for the voltage or current generation, and their interrelations, can be effectively extracted using the proposed convolutional residual blocks, and can simultaneously be exploited to regress for accurate SOCs. The performance of the proposed network model was evaluated using the data obtained from a lithium-ion battery (Panasonic NCR18650PF) under nine different driving schedules at five ambient temperatures. The experimental results demonstrated an average mean absolute error of 1.260%, and an average root-mean-square error of 0.998%. The number of floating-point operations required to complete one SOC estimation was 2.24 × 106. These results indicate the efficacy and performance of the proposed approach.
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Fontes de Energia Elétrica , Lítio , Íons , Redes Neurais de ComputaçãoRESUMO
Macroglial cells in the central nervous system exhibit regional specialization and carry out region-specific functions. Diverse glial cells arise from specific progenitors in specific spatiotemporal patterns. This raises an interesting possibility that glial precursors with distinct developmental fates exist that govern region-specific gliogenesis. Here, we have mapped the glial progeny produced by the Drosophila type II neuroblasts, which, like vertebrate radial glia cells, yield both neurons and glia via intermediate neural progenitors (INPs). Distinct type II neuroblasts produce different characteristic sets of glia. A single INP can make both astrocyte-like and ensheathing glia, which co-occupy a relatively restrictive subdomain. Blocking apoptosis uncovers further lineage distinctions in the specification, proliferation and survival of glial precursors. Both the switch from neurogenesis to gliogenesis and the subsequent glial expansion depend on Notch signaling. Taken together, lineage origins preconfigure the development of individual glial precursors with involvement of serial Notch actions in promoting gliogenesis.
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Encéfalo/embriologia , Proteínas de Drosophila/metabolismo , Drosophila/embriologia , Células-Tronco Neurais/citologia , Neurogênese/fisiologia , Receptores Notch/metabolismo , Animais , Apoptose/fisiologia , Astrócitos/citologia , Encéfalo/citologia , Linhagem da Célula/fisiologia , Proliferação de Células/fisiologia , Neurônios/citologiaRESUMO
Sensory systems allow for the transfer of environmental stimuli into internal cues that can alter physiology and behavior. Many studies of visual systems focus on opsins to compare spectral sensitivity among individuals, populations, and species living in different lighting environments. This requires an understanding of the cone opsins, which can be numerous. The bluefin killifish is a good model for studying the interaction between environments and visual systems as they are found in both clear springs and tannin-stained swamps. We conducted a genome-wide screening and demonstrated that the bluefin killifish has 9 cone opsins: 1 SWS1 (354 nm), 2 SWS2 (SWS2B: 359 nm, SWS2A: 448 nm), 2 RH2 (RH2-2: 476 nm, RH2-1: 537 nm), and 4 LWS (LWS-1: 569 nm, LWS-2: 524 nm, LWS-3: 569 nm, LWS-R: 560 or 569 nm). These 9 cone opsins were located on 4 scaffolds. One scaffold contained the 2 SWS2 and 3 of the 4 LWS opsins in the same syntenic order as found in other cyprinodontoid fishes. We also compared opsin expression in larval and adult killifish under clear water conditions, which mimic springs. Two of the newly discovered opsins (LWS-2 and LWS-3) were expressed at low levels (<0.2%). Whether these opsins make meaningful contributions to visual perception in other contexts (i.e., swamp conditions) is unclear. In contrast, there was an ontogenetic change from using LWS-R to LWS-1 opsin. Bluefin killifish adults may be slightly more sensitive to longer wavelengths, which might be related to sexual selection and/or foraging preferences.
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Opsinas dos Cones , Proteínas de Peixes , Fundulidae , Animais , Opsinas dos Cones/genética , Proteínas de Peixes/genética , Fundulidae/genética , Filogenia , Opsinas de Bastonetes/genética , Análise de SequênciaRESUMO
BACKGROUND: Insomnia is a common sleep disturbance in older adults and is associated with many poor health outcomes. This study aimed to explore factors associated with insomnia in older adult outpatient clinics, and to further analyze the influence of gender on factors associated with insomnia. METHODS: This cross-sectional study was conducted in the outpatient clinics of a tertiary hospital in Southern Taiwan from July to September 2018. A total of 400 consecutive subjects aged 60 years or older were recruited. Insomnia was defined as a score of ≥6 points on the Athens Insomnia Scale (AIS). Socio-demographics, health behaviors and clinical data were collected by face-to-face interview. Multivariable logistic regression was adopted for statistical analysis of the entire sample and stratified by gender. RESULTS: Participants' mean age was 74.74 ± 8.54 years, and the majority (93%) had more than one chronic disease. The prevalence of insomnia accounted for 30% (120/400) of all subjects, with males 22.9% (46/201) and females 37.2% (74/199). Gender, appetite, exercise, depressive symptoms, and sleep-related conditions such as short sleep duration, sleeping pills usage, medium-high risk of obstructive sleep apnea (OSA) and restless leg syndrome (RLS) were factors associated with insomnia in older adults. Exercise, sleeping pills usage, and RLS were independently associated with insomnia only in men, while appetite and medium-high risk of OSA were associated with insomnia in women only. In addition, after further adjusting for covariates, prevalence of the insomnia-related symptoms such as sleep induction, total sleep duration, sleep quality and sleepiness during the day was significantly higher in females than in males. CONCLUSIONS: Insomnia symptoms are highly prevalent among older adults, predominantly females. Significant differences are found between genders in factors associated with insomnia and insomnia-related symptoms. Understanding gender differences may help clinicians to modify associated factors when managing older adults with insomnia.
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Apneia Obstrutiva do Sono , Distúrbios do Início e da Manutenção do Sono , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pacientes Ambulatoriais , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Qualidade do SonoRESUMO
This study evaluated the effect of extreme temperatures on events requiring emergency room visits (ERVs) for hypertensive disease, ischemic heart disease (IHD), cerebrovascular disease, and chronic kidney disease (CKD) for population stratified by sex and age living in Taiwan's metropolitan city from 2000 to 2014. The distributed lag non-linear model was adopted to examine the association between ambient temperature and area-age-sex-disease-specific ERVs for a population aged 40 years and above. The reference temperature was defined by a percentile value to describe the temperature in each city. Area-age-sex-disease-specific relative risk (RR) and 95% confidence intervals (CI) were estimated in association with extreme high (99th percentile) and low (5th percentile) temperatures. Temperature-related ERV risks varied by area, age, sex, and disease. Patients with CKD tend to have comorbidities with hypertensive disease. All study populations with hypertensive disease have significant risk associations with extreme low temperatures with the highest RR of 2.64 (95% CI: 2.08, 3.36) appearing in New Taipei City. The risk of IHD was significantly associated with extreme high temperature for male subpopulation aged 40-64 years. A less significant association was observed between the risks of cerebrovascular disease with extreme temperature. The risk of CKD was most significantly associated with extreme high temperature especially for a subpopulation aged 40-64 years. All study subpopulations with hypertensive disease have significant risk associations with extreme low temperature. Male subpopulations were more vulnerable to extreme temperatures, especially for those aged 40-64 years.
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Serviço Hospitalar de Emergência , Temperatura Alta , Adulto , Temperatura Baixa , Comorbidade , Humanos , Masculino , TemperaturaRESUMO
The milkfish Chanos chanos, an economically important cultured marine species in Southeast Asia, exhibits stenothermal and euryhaline characteristics and huge mortality usually occurs during extreme cold weather in winter. Under conditions beyond optimal temperatures, ectothermic species experience an increase in anaerobic glycolysis. To better understand the hypothermal acclimation response of this tropical species, the lactate metabolic profiles of freshwater (FW)- and seawater (SW)-acclimated milkfish were compared under control (optimal temperature; 28 °C) and hypothermal treatment (18 °C) conditions. In this study, the lactate dehydrogenase (LDH) isoform genes, ldha and ldhb, were identified in milkfish livers and muscles, respectively. The LDH is a bidirectional enzyme that triggered the conversion of pyruvate to lactate via anaerobic glycolysis as LDH exhibits the reductase activity (LDH-R), while via the reverse direction as LDH exhibits the oxidase activity (LDH-O). The hypothermal stress significantly upregulated the LDH-R activity in the muscles and the monocarboxylate transporter activity in both muscles and livers, of SW- and FW-acclimated milkfish. The levels of blood lactate, however, decreased in SW-acclimated milkfish. Under hypothermal stress, anaerobic metabolism increased in the muscles of both FW and SW individuals, whereas the liver of SW-acclimated milkfish showed better acute phase capacity to utilize blood lactate than FW-acclimated milkfish. Taken together, in the present study, the major functions of the bidirectional enzyme LDH were identified according to its LDH-O and LDH-R activities. Furthermore, environmental salinities were found to affect the acute anaerobic metabolic strategies of euryhaline teleosts under hypothermal stress and were correlated with their hypothermal tolerance ability.
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Aclimatação/fisiologia , Peixes/fisiologia , Estresse Fisiológico , Animais , Glicemia/metabolismo , Água Doce , Brânquias/metabolismo , Homeostase , L-Lactato Desidrogenase/metabolismo , Ácido Láctico/sangue , Oxirredutases/metabolismo , Filogenia , Isoformas de Proteínas , Salinidade , Água do Mar , Temperatura , Distribuição TecidualRESUMO
In euryhaline teleosts, osmoregulatory mechanisms vary with osmotic stresses, and heat shock proteins (HSPs) play a central role in maintaining cellular homeostasis. The present study aimed to investigate the expression and potential roles of HSP70 and HSP90 in the gills of seawater (SW)- and freshwater (FW)-acclimated milkfish (Chanos chanos). Four HSP genes, including Cchsc70 (heat shock cognate 70), Cchsp70, Cchsp90α, and Cchsp90ß, were analyzed in milkfish gills. Among these genes, only the mRNA abundance of branchial Cchsp90α was significantly lower in the FW-acclimated than in the SW-acclimated milkfish. Immunoblotting showed no significant difference in the relative protein abundance of branchial HSP70 and HSP90 between the two groups. The time-course experiments (from SW to FW) showed that the protein abundance of HSP70 and HSP90 at the 3 h and 6 h post-transfer and then declined gradually. To further illustrate the potential osmoregulatory roles of HSP70 and HSP90, their interaction with Na+, K+-ATPase (NKA, the primary driving force for osmoregulation) was analyzed using co-immunoprecipitation. The results showed the interaction between HSP70, HSP90 and NKA after acclimation to SW or FW increased within 3 h; and then returned to normal levels within 7 days. To our knowledge, the present study was the first to demonstrate that the interaction between HSP70, HSP90 and NKA changes with hypotonic stress in euryhaline teleosts. Before the transfer, no interaction was detected. When transferred to FW from SW, the interaction of HSP70 and HSP90 with NKA were detected. The results suggested that HSP70 and HSP90 participated in the acute responses of osmoregulatory mechanisms to protect branchial NKA from hypotonic stress in milkfish.
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Peixes/fisiologia , Proteínas de Choque Térmico/metabolismo , Pressão Osmótica , ATPase Trocadora de Sódio-Potássio/metabolismo , Equilíbrio Hidroeletrolítico/fisiologia , Aclimatação/fisiologia , Animais , Peixes/metabolismo , Água Doce , Brânquias/metabolismo , Osmorregulação , Salinidade , Água do Mar , Sódio/metabolismo , Estresse FisiológicoRESUMO
Exposures to low ambient temperature require ectothermic fish to not only adjust their metabolic machinery but also to mount protective responses against oxidative stress. In this study, we tested whether diets supplemented with resveratrol (RSV), a naturally occurring polyphenol known to stimulate metabolic and protective responses in various animals, would be beneficial to tilapia (Oreochromis mossambicus) under hypothermic challenge. Feeding tilapia with RSV-supplemented diet promoted liver expression of sirtuins and their known targets, including metabolic/antioxidative enzymes. After exposure to 15 °C cold conditions for three days, the oxygen-nitrogen (O:N) ratio was decreased in the control-diet-fed tilapia but not in their RSV-fed counterparts. Moreover, at 27 °C, RSV-fed tilapia showed significantly higher prolonged swim speed compared with controls. RSV feeding produced no significant effect on upper and bottom layer preference between the control- and RSV-treated tilapia at either 27 °C or 15 °C. Together, these findings suggest that RSV stimulates beneficial metabolic/antioxidative adjustments in teleosts and may serve as a valuable feed supplement for tropical fish exposed to cold stress during winter.
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Ração Animal/análise , Antioxidantes/metabolismo , Fígado/metabolismo , Substâncias Protetoras/metabolismo , Resveratrol/metabolismo , Sirtuínas/metabolismo , Tilápia/metabolismo , Compostos de Amônio/metabolismo , Animais , Temperatura Baixa , Resposta ao Choque Frio , Regulação da Expressão Gênica/genética , Fígado/enzimologia , Locomoção/genética , Consumo de Oxigênio , Sirtuínas/genéticaRESUMO
Cerebral ischemia-reperfusion(I/R) injury is an important cause of acute ischemic stroke. Timely elimination of damaged proteins and organelles by regulating autophagy during cerebral ischemia-reperfusion plays an important role in relieving brain damage. In order to investigate whether ß-caryophyllene(BCP) could protect neurons from cerebral I/R injury by regulating auto-phagy, C57 BL/6 J male mice were randomly divided into sham operation group, model group, and drug-administered group. After intra-gastric administration was given for 5 days, the middle cerebral artery occlusion(MCAO) model was established by suture method. Twenty four hours after surgery, the infarct volume and neurological function were assessed; the pathological changes of cortical tissue were observed by HE staining; Western blot was used to detect the expression of autophagy-related proteins beclin1, p62, LC3 B and apoptosis-related protein Bcl-2; immunofluorescence was used to observe the expression of LC3 B in the ischemic cortex. The autophagy of cortical tissue in the ischemic area was observed by transmission electron microscopy. The experimental results showed that as compared with the model group, the BCP pretreatment significantly reduced the neurological deficit, decreased the percentage of cerebral infarction volume, reduced the death of brain tissue cells in the ischemic area, up-regulated the expression of beclin1, LC3 B and Bcl-2 protein, down-regulated p62 protein expression, and significantly increased the number of autophagosomes in the cortical tissue of the ischemic area. It was finally determined that BCP could protect neurons from cerebral ischemia-reperfusion injury by activating autophagy.
Assuntos
Autofagia , Isquemia Encefálica/tratamento farmacológico , Sesquiterpenos Policíclicos/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Infarto da Artéria Cerebral Média , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Distribuição AleatóriaRESUMO
Chronic hepatitis B virus (HBV) infection is the major cause of hepatocellular carcinoma (HCC). The pre-S2 mutant large HBV surface antigen (LHBS) is highly associated with HCC. This study analyzed the expression of the large form of surface protein in tumors and evaluated the LHBS with mutations within the pre-S2 region as a high-risk recurrence marker in HCC patients after curative hepatic resection. By analyses using immunohistochemical staining (n = 12) and western blotting (n = 22), the HBV surface protein, which is mainly comprised of the major form of HBV surface antigen, was greatly diminished in the tumors. However, LHBS was not significantly decreased in tumorous regions, suggesting that LHBS maintains its expression in cancer development. A cohort of 175 patients with HBV-related HCC who underwent curative hepatic resection was analyzed for pre-S gene mutations using Pre-S Gene Chip. Results of the multivariate regression analysis showed that the serum pre-S2 mutant level and the American Joint Committee on Cancer stage were the two main independent high-risk factors for recurrence. A Cox proportional hazards analysis also revealed a prediction model, which indicated the recurrence-free survival rate along with the time after surgery; this was developed and further validated in an independent HCC cohort. Receiver operating characteristic curve analysis revealed that the model showed close sensitivities in the main and validation cohorts (area under the curve values, 0.741 and 0.704, respectively). Conclusion: Unlike the major HBV surface antigen, LHBS is mostly expressed in the tumorous regions of HBV-induced HCC, indicating that it plays a unique role in tumor progression; the relative level of pre-S2 mutant in serum is, independently of tumor stage, an important high-risk marker for HCC recurrence after primary hepatic resection. (Hepatology 2018).