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BACKGROUND: The operation accuracy and efficiency of dynamic navigated endodontic surgery were evaluated through in vitro experiments. This study provides a reference for future clinical application of dynamic navigation systems in endodontic surgery. MATERIALS AND METHODS: 3D-printed maxillary anterior teeth were used in the preparation of models for endodontic surgery. Endodontic surgery was performed with and without dynamic navigation by an operator who was proficient in dynamic navigation technology but had no experience in endodontic surgery. Optical scanning data were applied to evaluate the length and angle deviations of root-end resection. And the operation time was recorded. T tests were used to analyze the effect of dynamic navigation technology on the accuracy and duration of endodontic surgery. RESULTS: With dynamic navigation, the root-end resection length deviation was 0.46 ± 0.06 mm, the angle deviation was 2.45 ± 0.96°, and the operation time was 187 ± 22.97 s. Without dynamic navigation, the root-end resection length deviation was 1.20 ± 0.92 mm, the angle deviation was 16.20 ± 9.59°, and the operation time was 247 ± 61.47 s. Less deviation was achieved and less operation time was spent with than without dynamic navigation (P < 0.01). CONCLUSION: The application of a dynamic navigation system in endodontic surgery can improve the accuracy and efficiency significantly for operators without surgical experience and reduce the operation time.
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Impressão Tridimensional , Humanos , Projetos Piloto , Técnicas In Vitro , Cirurgia Assistida por Computador/métodos , Apicectomia/métodos , Duração da Cirurgia , Sistemas de Navegação CirúrgicaRESUMO
Vibrio collagenases of the M9A subfamily are closely related to Vibrio pathogenesis for their role in collagen degradation during host invasion. Although some Vibrio collagenases have been characterized, the collagen degradation mechanism of Vibrio collagenase is still largely unknown. Here, an M9A collagenase, VP397, from marine Vibrio pomeroyi strain 12613 was characterized, and its fragmentation pattern on insoluble type I collagen fibers was studied. VP397 is a typical Vibrio collagenase composed of a catalytic module featuring a peptidase M9N domain and a peptidase M9 domain and two accessory bacterial prepeptidase C-terminal domains (PPC domains). It can hydrolyze various collagenous substrates, including fish collagen, mammalian collagens of types I to V, triple-helical peptide [(POG)10]3, gelatin, and 4-phenylazobenzyloxycarbonyl-Pro-Leu-Gly-Pro-o-Arg (Pz-peptide). Atomic force microscopy (AFM) observation and biochemical analyses revealed that VP397 first assaults the C-telopeptide region to dismantle the compact structure of collagen and dissociate tropocollagen fragments, which are further digested into peptides and amino acids by VP397 mainly at the Y-Gly bonds in the repeating Gly-X-Y triplets. In addition, domain deletion mutagenesis showed that the catalytic module of VP397 alone is capable of hydrolyzing type I collagen fibers and that its C-terminal PPC2 domain functions as a collagen-binding domain during collagenolysis. Based on our results, a model for the collagenolytic mechanism of VP397 is proposed. This study sheds light on the mechanism of collagen degradation by Vibrio collagenase, offering a better understanding of the pathogenesis of Vibrio and helping in developing the potential applications of Vibrio collagenase in industrial and medical areas. IMPORTANCE Many Vibrio species are pathogens and cause serious diseases in humans and aquatic animals. The collagenases produced by pathogenic Vibrio species have been regarded as important virulence factors, which occasionally exhibit direct pathogenicity to the infected host or facilitate other toxins' diffusion through the digestion of host collagen. However, our knowledge concerning the collagen degradation mechanism of Vibrio collagenase is still limited. This study reveals the degradation strategy of Vibrio collagenase VP397 on type I collagen. VP397 binds on collagen fibrils via its C-terminal PPC2 domain, and its catalytic module first assaults the C-telopeptide region and then attacks the Y-Gly bonds in the dissociated tropocollagen fragments to release peptides and amino acids. This study offers new knowledge regarding the collagenolytic mechanism of Vibrio collagenase, which is helpful for better understanding the role of collagenase in Vibrio pathogenesis and for developing its industrial and medical applications.
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Colágeno Tipo I , Vibrio , Sequência de Aminoácidos , Aminoácidos , Animais , Colágeno/metabolismo , Colágeno Tipo I/genética , Colagenases/genética , Colagenases/metabolismo , Mamíferos , Peptídeos/metabolismo , Tropocolágeno , Vibrio/metabolismoRESUMO
Bacterial polar flagella, comprised of flagellin, are essential for bacterial motility. Pseudoalteromonas sp. strain SM9913 is a bacterium isolated from deep-sea sediments. Unlike other Pseudoalteromonas strains that have a long polar flagellum, strain SM9913 has an abnormally short polar flagellum. Here, we investigated the underlying reason for the short flagellum and found that a single-base mutation was responsible for the altered flagellar assembly. This mutation leads to the fragmentation of the flagellin gene into two genes, PSM_A2281, encoding the core segment and the C-terminal segment, and PSM_A2282, encoding the N-terminal segment, and only gene PSM_A2281 is involved in the production of the short polar flagellum. When a chimeric gene of PSM_A2281 and PSM_A2282 encoding an intact flagellin, A2281::82, was expressed, a long polar flagellum was produced, indicating that the N-terminal segment of flagellin contributes to the production of a polar flagellum of a normal length. Analyses of the simulated structures of A2281 and A2281::82 and that of the flagellar filament assembled with A2281::82 indicate that due to the lack of two α-helices, the core of the flagellar filament assembled with A2281 is incomplete and is likely too weak to support the stability and movement of a long flagellum. This mutation in strain SM9913 had little effect on its growth and only a small effect on its swimming motility, implying that strain SM9913 can live well with this mutation in natural sedimentary environments. This study provides a better understanding of the assembly and production of bacterial flagella. IMPORTANCE Polar flagella, which are essential organelles for bacterial motility, are comprised of multiple flagellin subunits. A flagellin molecule contains an N-terminal segment, a core segment, and a C-terminal segment. The results of this investigation of the deep-sea sedimentary bacterium Pseudoalteromonas sp. strain SM9913 demonstrate that a single-base mutation in the flagellin gene leads to the production of an incomplete flagellin without the N-terminal segment and that the loss of the N-terminal segment of the flagellin protein results in the production of a shortened polar flagellar filament. Our results shed light on the important function of the N-terminal segment of flagellin in the assembly and stability of bacterial flagellar filament.
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Flagelina , Pseudoalteromonas , Flagelos/genética , Flagelina/genética , Sedimentos Geológicos/microbiologia , Mutação , Pseudoalteromonas/genética , Água do Mar/microbiologiaRESUMO
Cell division of Staphylococcus adopts a "popping" mechanism that mediates extremely rapid separation of the septum. Elucidating the structure of the septum is crucial for understanding this exceptional bacterial cell division mechanism. Here, the septum structure of Staphylococcus warneri was extensively characterized using high-speed time-lapse confocal microscopy, atomic force microscopy, and electron microscopy. The cells of S. warneri divide in a fast popping manner on a millisecond timescale. Our results show that the septum is composed of two separable layers, providing a structural basis for the ultrafast daughter cell separation. The septum is formed progressively toward the center with nonuniform thickness of the septal disk in radial directions. The peptidoglycan on the inner surface of double-layered septa is organized into concentric rings, which are generated along with septum formation. Moreover, this study signifies the importance of new septum formation in initiating new cell cycles. This work unravels the structural basis underlying the popping mechanism that drives S. warneri cell division and reveals a generic structure of the bacterial cell.IMPORTANCE This work shows that the septum of Staphylococcus warneri is composed of two layers and that the peptidoglycan on the inner surface of the double-layered septum is organized into concentric rings. Moreover, new cell cycles of S. warneri can be initiated before the previous cell cycle is complete. This work advances our knowledge about a basic structure of bacterial cell and provides information on the double-layered structure of the septum for bacteria that divide with the "popping" mechanism.
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Divisão Celular , Parede Celular/ultraestrutura , Microscopia de Força Atômica/métodos , Staphylococcus/ultraestrutura , Ciclo Celular , Microscopia Eletrônica , Peptidoglicano , Staphylococcus aureusRESUMO
The one-dimensional (1D) ABX3-type perovskite [(CH3)3PCH2F]CdCl2Br (1) has been obtained on the basis of the design of an organic-inorganic hybrid. Strikingly, it experiences sequential phase transitions at around 295 and 336 K, respectively. Given the noticeable steplike dielectric anomalies in the vicinity of 295 K, 1 is identified as a promising dielectric-switchable material. According to the single-crystal structure analysis, the order-to-disorder transformation of the [(CH3)3PCH2F]+ cation is the main reason for the phase transitions and the change of space group from the orthorhombic Pnma (No. 62) to the hexagonal P63/m (No. 176). This design of a perovskite structure will inspire more advances in the ever-growing field of switchable functional materials.
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Supramolecular chemistry addresses intermolecular forces and consequently promises great flexibility and precision. Biological systems are often the inspirations for supramolecular research. The G-quadruplex (G4) belongs to one of the most important secondary structures in nucleic acids. Until recently, the supramolecular manipulation of the G4 has not been reported. The present study is the first to disclose a supramolecular switch for the reversible control of human telomere G4s. Moreover, this supramolecular switch has been successfully used to manipulate an enzymatic reaction. Using various methods, we show that cucurbit[7]uril preferably locks and encapsulates the positively charged piperidines of Razo through supramolecular interactions. They can switch the conformations of the DNA inhibitor between a flexible state and the rigid G4 and are therefore responsible for the reversible control of the thrombin activity. Thus, our findings open a promising route and exhibit potential applications in future studies of chemical biology.
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Hidrocarbonetos Aromáticos com Pontes/farmacologia , DNA/química , Quadruplex G/efeitos dos fármacos , Imidazóis/farmacologia , Trombina/química , Compostos Azo/química , Sequência de Bases , Hidrocarbonetos Aromáticos com Pontes/química , Humanos , Imidazóis/química , Simulação de Acoplamento Molecular , Piperidinas/química , Telômero/química , Telômero/efeitos dos fármacos , Trombina/metabolismoRESUMO
5-Formylcytosine (5fC) is identified as one of the key players in active DNA demethylation and also as an epigenetic mark in mammals, thus representing a novel attractive target to chemical intervention. The current study represents an attempt to develop a reversible 5fC-targeted intervention tool. A supramolecular aldehyde reactive probe was therefore introduced for selective conversion of the 5fC to 5fC-AD nucleotide. Using various methods, we demonstrate that cucurbit[7]uril (CB7) selectively targets the 5fC-AD nucleotide in DNA, however, the binding of CB7 to 5fC-AD does not affect the hydrogen bonding properties of natural nucleobases in duplex DNA. Importantly, CB7-driven host-guest chemistry has been applied for reversible intervention of a variety of 5fC-targeted biochemical reactions, including restriction endonuclease digestion, DNA polymerase elongation, and polymerase chain reaction. On the basis of the current study, the macrocyclic CB7 creates obstructions that, through steric hindrance, prevent the enzyme from binding to the substrate, whereas the CB7/5fC-AD host-guest interactions can be reversed by treatment with adamantanamine. Moreover, fragment- and site-specific identification of 5fC modification in DNA has been accomplished without sequence restrictions. These findings thus show promising potential of host-guest chemistry for DNA/RNA epigenetics.
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Adamantano/metabolismo , Aldeídos/metabolismo , Hidrocarbonetos Aromáticos com Pontes/metabolismo , Citosina/análogos & derivados , Imidazóis/metabolismo , Sondas Moleculares/metabolismo , Nucleosídeos/metabolismo , Adamantano/química , Aldeídos/química , Hidrocarbonetos Aromáticos com Pontes/química , Citosina/química , Citosina/metabolismo , DNA/química , DNA/metabolismo , Imidazóis/química , Sondas Moleculares/química , Estrutura Molecular , Nucleosídeos/químicaRESUMO
Environmental exposure to heavy metals has been linked to a wide range of human health hazards. We detected the levels of 15 metals in urine samples from 500 representative sub-samples in an ongoing occupational cohort study (Jinchang Cohort) to directly evaluate metal exposure levels. Fifteen metals, namely As, Ba, Be, Cd, Cs, Cr, Co, Cu, Pb, Mn, Ni, Se, Tl, U, and Zn, were detected by inductively coupled plasma quadruple mass spectrometry. The results showed that median creatinine adjustment and geometric mean urinary metal levels were higher in the heavy metal-exposed group, except Se and Zn, than other reported general or occupational populations. Further studies should address the effects of heavy metals on human health.
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Poluentes Ambientais/sangue , Metais Pesados/sangue , Exposição Ocupacional , China , Estudos de Coortes , HumanosRESUMO
OBJECTIVE: To study the association between metal exposure and risk of diabetes and prediabetes among Chinese workers exposed to metals. METHODS: We used data obtained from the baseline survey of the Jinchang Cohort Study of workers in Jinchang Industry, the largest nickel production company in China. A total of 42,122 workers â20 years of age were included in the study. A standardized, structured questionnaire was used to collect epidemiological information. Physical examinations and laboratory tests were conducted to evaluate the health status of the participants and to measure various biomarkers including blood sugar, lipids, and urinary metal concentrations. Logistic regression was used to study the association between occupational groups categorized according to the measured metal levels (office workers, low-level; mining/production workers, mid-level; and smelting/refining workers, high-level) and risk of diabetes and prediabetes. RESULTS: The overall prevalence of diabetes and prediabetes was 7.5% and 16.8%, respectively. The adjusted odds ratios for diabetes among mining/production workers and smelting/refining workers compared to office workers were 1.5 (95% CI: 1.3, 1.7) and 3.8 (95% CI: 3.4, 4.3), respectively. No association was observed between these occupational groups and prediabetes in this study. CONCLUSION: Occupations associated with higher levels of metal exposure were associated with an increased risk of diabetes in this cohort. More studies are needed to confirm this observed association.
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Metais Pesados/toxicidade , Exposição Ocupacional/efeitos adversos , Estado Pré-Diabético/induzido quimicamente , Adulto , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Masculino , Metais Pesados/urina , Pessoa de Meia-Idade , Estado Pré-Diabético/epidemiologiaRESUMO
Background: Sarcopenia, common in the elderly, often linked to chronic diseases, correlates with inflammation.The association between SII and mortality in sarcopenia patients is underexplored, this study investigates this relationship in a U.S. adult cohort. Methods: We analyzed 1999-2018 NHANES data, focusing on 2,974 adults with sarcopenia. Mortality outcomes were determined by linking to National Death Index (NDI) records up to December 31, 2019. Using a weighted sampling design, participants were grouped into three groups by the Systemic Immune-Inflammation Index (SII). We used Cox regression models, adjusting for demographic and clinical variables, to explore SII's association with all-cause and cause-specific mortality in sarcopenia, performing sensitivity analyses for robustness. Results: Over a median follow-up of 9.2 years, 829 deaths occurred. Kaplan-Meier analysis showed significant survival differences across SII groups. The highest SII group showed higher hazard ratios (HRs) for all-cause and cause-specific mortality in both crude and adjusted models. The highest SII group had a higher HR for all-cause(1.57, 1.25-1.98), cardiovascular(1.61, 1.00-2.58), cancer(2.13, 1.32-3.44), and respiratory disease mortality(3.21, 1.66-6.19) in fully adjusted models. Subgroup analyses revealed SII's association with all-cause mortality across various demographics, including age, gender, and presence of diabetes or cardiovascular disease. Sensitivity analyses, excluding participants with cardiovascular diseases, those who died within two years of follow-up, or those under 45 years of age, largely reflected these results, with the highest SII group consistently demonstrating higher HRs for all types of mortality in both unadjusted and adjusted models. Conclusion: Our study is the first to demonstrate a significant relationship between SII and increased mortality risks in a sarcopenia population.
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Doenças Cardiovasculares , Sarcopenia , Adulto , Idoso , Humanos , Causas de Morte , Inquéritos Nutricionais , InflamaçãoRESUMO
Braun's lipoprotein (Lpp) plays a major role in stabilizing the integrity of the cell envelope in Escherichia coli, as it provides a covalent cross-link between the outer membrane and the peptidoglycan layer. An important challenge in elucidating the physiological role of Lpp lies in attaining a detailed understanding of its distribution on the peptidoglycan layer. Here, using atomic force microscopy, we visualized Lpp directly on peptidoglycan sacculi. Lpp is homogeneously distributed over the outer surface of the sacculus at a high density. However, it is absent at the constriction site during cell division, revealing its role in the cell division process with Pal, another cell envelope-associated protein. Collectively, we have established a framework to elucidate the distribution of Lpp and other peptidoglycan-bound proteins via a direct imaging modality.
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Escherichia coli , Lipoproteínas , Microscopia de Força Atômica , Imagem Molecular , Proteínas da Membrana Bacteriana Externa/metabolismo , Membrana Celular/metabolismo , Escherichia coli/química , Lipoproteínas/química , Peptidoglicano/química , Imagem Molecular/métodosRESUMO
Several genetic loci (JAZF1, CDC123/CAMK1D, TSPAN8/LGR5, ADAMTS9, VEGFA and HHEX-IDE) were identified to be significantly related to the risk of type 2 diabetes and quantitative metabolic traits in European populations. Here, we aimed to evaluate the impacts of these novel loci on type 2 diabetes risk in a population-based case-control study of Han Chinese (1912 cases and 2041 controls). We genotyped 13 single-nucleotide polymorphisms (SNPs) in/near these genes and examined the differences in allele/genotype frequency between cases and controls. We found that both IDE rs11187007 and HHEX rs1111875 were associated with type 2 diabetes risk (for both variants: odds ratio (OR)=1.15, 95% confidence interval (CI) 1.04-1.28, P=0.009). In a meta-analysis where we pooled our data with the three previous studies conducted in East Asians, we found that the variants of JAZF1 rs864745 (1.09 (1.03-1.16); P=3.49 × 10(-3)) and TSPAN8/LGR5 rs7961581 (1.11(1.05-1.17); P=1.89 × 10(-4)) were significantly associated with type 2 diabetes risk. In addition, the meta-analysis (7207 cases and 8260 controls) also showed that HHEX rs1111875 did have effects on type 2 diabetes in Chinese population (OR=1.15(1.10-1.21); P=1.93 × 10(-8)). This large population-based study and meta-analysis further confirmed the modest effects of the JAZF1, TSPAN8/LGR5 and HHEX-IDE loci on type 2 diabetes in Chinese and other East Asians.
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Antígenos de Neoplasias/genética , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Proteínas de Homeodomínio/genética , Glicoproteínas de Membrana/genética , Proteínas de Neoplasias/genética , Receptores Acoplados a Proteínas G/genética , Fatores de Transcrição/genética , Idoso , Povo Asiático/genética , China/epidemiologia , Cromossomos Humanos Par 10/genética , Cromossomos Humanos Par 12/genética , Cromossomos Humanos Par 3/genética , Cromossomos Humanos Par 6/genética , Cromossomos Humanos Par 7/genética , Proteínas Correpressoras , Proteínas de Ligação a DNA , Feminino , Frequência do Gene , Loci Gênicos , Variação Genética , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Risco , TetraspaninasRESUMO
Cardiovascular disease (CVD) and environmental degradation are leading global health problems of our time. Recent studies have linked exposure to heavy metals to the risks of CVD and diabetes, particularly in populations from low- and middle-income countries, where concomitant rapid development occurs. In this review, we 1) assessed the totality, quantity, and consistency of the available epidemiological studies, linking heavy metal exposures to the risk of CVD (including stroke and coronary heart disease); 2) discussed the potential biological mechanisms underlying some tantalizing observations in humans; and 3) identified gaps in our knowledge base that must be investigated in future work. An accumulating body of evidence from both experimental and observational studies implicates exposure to heavy metals, in a dose-response manner, in the increased risk of CVD. The limitations of most existing studies include insufficient statistical power, lack of comprehensive assessment of exposure, and cross-sectional design. Given the widespread exposure to heavy metals, an urgent need has emerged to investigate these putative associations of environmental exposures, either independently or jointly, with incident CVD outcomes prospectively in well-characterized cohorts of diverse populations, and to determine potential strategies to prevent and control the impacts of heavy metal exposure on the cardiometabolic health outcomes of individuals and populations.
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OBJECTIVE: This study investigated the prospective associations of circulating levels of sex hormone-binding globulin (SHBG) levels with cardiometabolic biomarkers and risk of gestational diabetes (GDM) during pregnancy. It also examines the longitudinal trajectory of SHBG in women with and without GDM. METHODS: We conducted a nested case-control study of 107 incident GDM cases and 214 matched controls within the Eunice Kennedy Shriver National Institute of Child Health and Human Development Fetal Growth Studies-Singleton Cohort. The cohort enrolled non-obese and obese women aged 18-40 years with a singleton pregnancy between 8 and 13 weeks of gestation from 2009 to 2013. GDM was ascertained via medical records review. Blood samples were drawn four times at gestational weeks 10-14, 15-26, 23-31, and 33-39. The prospective associations between SHBG levels and cardiometabolic biomarkers were examined using the Spearman partial correlation among the controls. The longitudinal trajectories of SHBG levels were examined among the cases and the controls. Meta-analysis of prospective studies were performed to examine the association between SHBG levels and GDM risk. RESULTS: SHBG levels at gestational weeks 10-14 were significantly inversely associated with fasting insulin (râ=â-0.17, Pâ=â0.01) and insulin resistance as measured by HOMA-IR (râ=â-0.17, Pâ=â0.01) at gestational week 15-26. SHBG at gestational weeks 10-14 and 15-26 was lower in cases than controls (mean ± standard deviation: (204.0â±â97.6) vs. (220.9â±â102.5) nmol/L, Pâ=â0.16 and (305.6â±â124.3) vs. (322.7â±â105.1) nmol/L, Pâ=â0.14, respectively), yet the differences were not significant. In the meta-analysis, SHBG was 41.5ânmol/L (95% confidence interval: 23.9, 59.1, Pâ<â0.01) significantly lower among women with GDM than without, and each 50ânmol/L increase in SHBG was significantly associated with an odds ratio of 0.85 (95% confidence interval: 0.76-0.95, Pâ=â0.01) for GDM. CONCLUSION: Lower SHBG levels in early pregnancy were prospectively associated with higher high insulin levels and insulin resistance in mid-pregnancy and subsequent risk of GDM, independent of adiposity. SHBG may serve as a marker for the identification of high-risk pregnancies during early pregnancy.
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BACKGROUND: Little is known about the role of specific leisure activities in affecting cognitive functions. We aim to examine the associations of specific leisure activities with the risk of cognitive impairment among oldest-old people in China. METHODS: This community-based prospective cohort study included 10,741 cognitively normal Chinese individuals aged 80 years or older (median age 88 years) from the Chinese Longitudinal Healthy Longevity Survey. Cognitive function was assessed using the Mini-Mental State Examination (MMSE). Cox proportional hazards models were utilized to estimate the effects of specific leisure activities on cognitive impairment outcome. RESULTS: During a median follow-up time of 3.4 years (41,760 person-years), 2,894 participants developed cognitive impairment. Compared to those who "never" engaged in watching TV or listening to radio, reading books or newspapers, and playing cards or mah-jong, those who engaged in such activities "almost every day" reduced their risk of cognitive impairment, the fully-adjusted hazard ratios were 0.56 (0.51-0.61), 0.64 (0.53-0.78), and 0.70 (0.56-0.86), respectively. The association between the risk of cognitive impairment and watching TV and listening to the radio, playing cards or mah-jong, and reading books or newspapers were stronger among those who had two or more years of education. Moreover, the association between risk of cognitive impairment and watching TV and listening to radio was stronger in men than in women. CONCLUSIONS: In conclusion, a greater frequency of TV watching or radio listening, reading books or newspapers, and playing cards or mah-jong may decrease the risk of cognitive impairment among the oldest-old.
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Cognição/fisiologia , Envelhecimento Saudável/psicologia , Atividades de Lazer/psicologia , Idoso de 80 Anos ou mais , Povo Asiático/psicologia , China/epidemiologia , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/prevenção & controle , Estudos de Coortes , Feminino , Inquéritos Epidemiológicos , Humanos , Estudos Longitudinais , Masculino , Estudos Prospectivos , Fatores de RiscoRESUMO
Masks have become one of the most indispensable pieces of personal protective equipment and are important strategic products during the coronavirus disease 2019 (COVID-19) pandemic. Due to the huge mask demand-supply gap all over the world, the development of user-friendly technologies and methods is urgently needed to effectively extend the service time of masks. In this article, we report a very simple approach for the decontamination of masks for multiple reuse during the COVID-19 pandemic. Used masks were soaked in hot water at a temperature greater than 56 °C for 30 min, based on a recommended method to kill COVID-19 virus by the National Health Commission of the People's Republic of China. The masks were then dried using an ordinary household hair dryer to recharge the masks with electrostatic charge to recover their filtration function (the so-called "hot water decontamination + charge regeneration" method). Three kinds of typical masks (disposable medical masks, surgical masks, and KN95-grade masks) were treated and tested. The filtration efficiencies of the regenerated masks were almost maintained and met the requirements of the respective standards. These findings should have important implications for the reuse of polypropylene masks during the COVID-19 pandemic. The performance evolution of masks during human wear was further studied, and a company (Zhejiang Runtu Co., Ltd.) applied this method to enable their workers to extend the use of masks. Mask use at the company was reduced from one mask per day per person to one mask every three days per person, and 122â500 masks were saved during the period from 20 February to 30 March 2020. Furthermore, a new method for detection of faulty masks based on the penetrant inspection of fluorescent nanoparticles was established, which may provide scientific guidance and technical methods for the future development of reusable masks, structural optimization, and the formulation of comprehensive performance evaluation standards.
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BACKGROUND: Evidence of the trend of the incidence of activities of daily living (ADL) disability among Chinese older people is limited. We aimed to investigate the time trends and potential risk factors for the incidence of ADL disability among Chinese older people (≥65 years). METHODS: We established two consecutive and nonoverlapping cohorts (6,857 participants in the 2002 cohort and 5,589 participants in the 2008 cohort) from the Chinese Longitudinal Healthy Longevity Survey. ADL disability was defined as the need for assistance with at least one essential activity (dressing, bathing, toileting, eating, indoor activities, and continence). Cox proportional hazards models were used to identify factors associated with the trend in the incidence of ADL disability from 2002 to 2014. RESULTS: The incidence (per 1,000 person-years) of ADL disability decreased significantly from 64.2 in the 2002 cohort to 46.6 in the 2008 cohort (p < .001), and decreasing trends in the incidence of ADL disability were observed for all sex, age, and residence subgroups (all p < .001), even after adjusting for multiple potential confounding factors. Moreover, we found that adjustment for sociodemographic, lifestyle information, and cardiovascular risk factors (hypertension, diabetes, heart disease, and stroke) explained less of the decline in ADL disability during the period from 2002 to 2014. CONCLUSION: The incidence of ADL disability among the older adults in China appears to have decreased during the study period, and this finding cannot be explained by existing sociodemographic and lifestyle information and cardiovascular risk factors.
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Atividades Cotidianas , Avaliação da Deficiência , Avaliação Geriátrica , Idoso , Idoso de 80 Anos ou mais , China , Feminino , Humanos , Incidência , Estudos Longitudinais , Masculino , Fatores de RiscoRESUMO
OBJECTIVE: To establish and promote the non-contact doctor-patient interactive diagnosis and treatment mode based on mobile internet for the treatment of coronavirus disease 2019 (COVID-19) with moxibustion therapy, and to observe the feasibility and effectiveness of the model in the pandemic. METHODS: A total of 43 first-line medical staff and 149 suspected and confirmed cases with COVID-19 [18 cases in medical observation period, 17 cases of mild type (cold dampness and stagnation in the lung), 24 cases of ordinary type (cold-dampness accumulated in the lung) and 90 cases in recovery period (qi deficiency of spleen and lung)] were included. A non-contact doctor-patient interactive diagnosis and treatment platform was established for the treatment of COVID-19 with indirect moxibustion plaster based on mobile internet. By the platform, the patients were instructed to use indirect moxibustion plaster in treatment. For the first-line medical staff and patients in the medical observation period, Zusanli (ST 36), Qihai (CV 6) and Zhongwan (CV 12) were selected. For the mild cases (cold dampness and stagnation in the lung) and the cases of ordinary type (cold-dampness accumulated in the lung), Hegu (LI 4), Taichong (LR 3), Zusanli (ST 36) and Guanyuan (CV 4) were selected. In the recovery period (qi deficiency of spleen and lung), Dazhui (GV 14), Feishu (BL 13), Geshu (BL 17), Zusanli (ST 36) and Kongzui (LU 6) were used. The treatment was given once daily for 40 min each time. The intervention lasted for 10 days. After intervention, the infection rate and the improvement in the symptoms and psychological status of COVID-19 were observed in clinical first-line medical staff and COVID-19 patients. RESULTS: In 10 days of intervention with indirect moxibustion plaster, there was "zero" infection among medical staff. Of 43 first-line physicians and nurses, 33 cases had some physical symptoms and psychological discomforts, mainly as low back pain, poor sleep and anxiety. After treatment, regarding the improvements in the symptoms and psychological discomforts, the effective rate was 78.8% (26/33) and the curative rate was 36.4% (12/33). Regarding the improvements in psychological discomforts, the effective rate was 58.3% (14/24) and the curative rate was 37.5 (9/24). Of 149 patients, 133 cases had the symptoms and psychological discomforts. After treatment, regarding the improvements in the symptoms and psychological discomforts, the effective rate was 81.2% (108/133) and the curative rate was 34.6% (46/133). Regarding the improvements in psychological discomforts, the effective rate was 76.5% (52/68) and the curative rate was 57.4 % (39/68). CONCLUSION: It is feasible to apply the indirect moxibustion plaster technique based on mobile internet to the treatment COVID-19. This mode not only relieves the symptoms such as cough and fatigue, improves psychological state, but also possibly prevents the first-line medical staff from COVID-19.
Assuntos
Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Moxibustão , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/terapia , Consulta Remota , Pontos de Acupuntura , Betacoronavirus , COVID-19 , Pessoal de Saúde , Humanos , SARS-CoV-2RESUMO
The predatory mite, Neoseiulus bicaudus (Wainstein), is a potential biological control agent against spider mites and thrips. The objective of this experiment was to compare the effects of three diets on the life table of N. bicaudus. The three diets were 1) Tetranychus turkestani (Ugarov & Nikolskii) (Acari: Tetranychidae), the natural prey of N. bicaudus; 2) Tyrophagus putrescentiae (Schrank) (Acari: Acaridae), an alternative prey; and 3) artificial diet primarily consisting of decapsulated shrimp cysts, egg yolk, and honey. The computer simulation was used to project the population growth of N. bicaudus fed on different diets. The preadult developmental time (3.83 d) of N. bicaudus was shortest, and the intrinsic rate of increase (r = 0.2782 d-1) and the net reproductive rate (R0 = 18.98 offspring) were highest when reared on the alternative prey Ty. putrescentiae. The total development time (7.37 d) was longest, and the population parameters were the lowest (r = -0.0081 d-1, R0 = 0.85 offspring) when N. bicaudus was reared on artificial diet. The population projection showed that the population of N. bicaudus reared on Ty. putrescentiae could increase fast. Our results showed that the Ty. putrescentiae was the most suitable prey for mass rearing of N. bicaudus. The artificial diet could not support the N. bicaudus population and needs to be improved.
Assuntos
Ácaros e Carrapatos , Ácaros , Tetranychidae , Animais , Simulação por Computador , Dieta , Controle Biológico de Vetores , Comportamento PredatórioRESUMO
BACKGROUND: Parathyroid hormone related protein (PTHrP) triggers white adipose tissue (WAT) browning and cachexia in lung cancer mouse models. It remains unknown whether excessive PTH secretion affects WAT browning and to what extent it contributes to body weight change in primary hyperparathyroidism (PHPT). METHODS: Using the adeno-associated virus injection, Pth gene over-expressed mice mimicking PHPT were firstly established to observe their WAT browning and body weight alteration. The association between PTH and body weight was investigated in 496 PHPT patients. The adipose browning activities of 20 PHPT and 60 control subjects were measured with PET/CT scanning. FINDINGS: Elevated plasma PTH triggered adipose tissue browning, leading to increased energy expenditure, reduced fat content, and finally decreased body weight in PHPT mice. Higher circulating PTH levels were associated with lower body weight (ßâ¯=â¯-0.048, Pâ¯=â¯.0003) independent of renal function, serum calcium, phosphorus,and albumin levels in PHPT patients. PHPT patients exhibited both higher prevalence of detectable brown/beige adipose tissue (20% vs 3.3%, Pâ¯=â¯.03) and increased browning activities (SUV in cervical adipose was 0.77 vs 0.49,Pâ¯=â¯.02) compared with control subjects. INTERPRETATION: Elevated serum PTH drove WAT browning program, which contributed in part to body weight loss in both PHPT mice and patients. These results give insights into the novel pathological effect of PTH and are of importance in understanding the metabolic changes of PHPT. FUND: This research is supported by the National Key Research and Development Program of China and National Natural Science Foundation of China.