RESUMO
Superlubricity has been recognized as the future of tribology. However, it is hard to achieve superlubricity under extreme conditions such as a high load and low sliding speed on the macroscale. In this paper, a remarkable synergetic lubricating effect between nanoparticles and silicon nitride (Si3N4) is demonstrated; this effect helps water-lubricated Si3N4 achieve superlubricity under extreme conditions successfully. Different kinds of hairy silica nanoparticles were prepared, dispersed into water, and characterized using a variety of methods. The tribological properties of water-lubricated Si3N4 with nanoparticle additives were tested using a ball-on-disk tribometer under different loads and sliding speeds. The coefficient of friction and wear scar diameter were measured and analyzed. Both the nanoparticle size and surface functional groups have a significant influence on the tribological properties of water-lubricated Si3N4. Amino-modified silica nanoparticles reduce the friction coefficient of water-lubricated Si3N4 by 82.9% under 60 N, compared with that achieved using deionized water, and induce superlubricity after the running-in process. Silica nanoparticles effectively form a homogenous film with silica gel on the worn surface under a high load and thus reduce the wear and maintain the superlubricity under extreme conditions.
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BACKGROUND: It has been suggested that tooth loss in later life might increase dementia incidence. The objective of this analysis is to systematically review the current evidence on the relationship between the number of remaining teeth and dementia occurrence in later life. METHODS: A search of multiple databases of scientific literature was conducted with relevant parameters for articles published up to March 25th, 2017. Multiple cohort studies that reported the incidence of dementia and residual teeth in later life were found with observation periods ranging from 2.4 to 32 years. Random-effects pooled odds ratios (OR) and 95% confidence intervals (CI) were estimated to examine whether high residual tooth number in later life was associated with a decreased risk of dementia. Heterogeneity was measured by I2. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system was used to assess the overall quality of evidence. RESULTS: The literature search initially yielded 419 articles and 11 studies (aged 52 to 75 at study enrollment, n = 28,894) were finally included for analysis. Compared to the low residual teeth number group, the high residual teeth number group was associated with a decreased risk of dementia by approximately 50% (pooled OR = 0.483; 95% CI 0.315 to 0.740; p < 0.001; I2 = 92.421%). The overall quality of evidence, however, was rated as very low. CONCLUSION: Despite limited scientific strength, the current meta-analysis reported that a higher number of residual teeth was associated with having a lower risk of dementia occurrence in later life.
Assuntos
Envelhecimento/patologia , Demência/diagnóstico , Demência/epidemiologia , Perda de Dente/diagnóstico , Perda de Dente/epidemiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , Demência/psicologia , Humanos , Incidência , Pessoa de Meia-Idade , Perda de Dente/psicologiaRESUMO
BACKGROUND & AIMS: In 2009, the U.S. Department of Justice issued a memo stating that it would not prosecute users and sellers who complied with the state laws allowing for medical use of marijuana. There are growing concerns about legalization of marijuana use and its related public health effects. We performed an interrupted time series analysis to evaluate these effects. METHODS: We collected a representative sample of hospital discharge data from the Healthcare Cost and Utilization Project, from January 1993 to December 2014. We divided the data in to 3 groups: the prelegalization period (1993-2008), the legalization period (2009), and the postlegalization period (2010-2014). The disease variables were International Classification of Disease-Ninth Revision-Clinical Modification 304.30 cannabinoid dependency unspecified (CDU), 536.2 persistent vomiting, and an aggregate of CDU and persistent vomiting. We performed interrupted time series and Poisson-Gamma regression analysis to calculate each year's incidence rate of unspecified and persistent vomiting and CDU per 100,000 hospital discharges. CDU, persistent vomiting, and aggregate of CDU and persistent vomiting were modeled separately to estimate average incidence rate ratio and 95% confidence interval for each study phase. RESULTS: We observed an increasing trend of CDU or an aggregate of CDU and persistent vomiting during the prelegalization period. The legalization of marijuana significantly increased the incidence rate during the legalization period (by 17.9%) and the yearly average increase in rate by 6% after policy implementation, compared to the prelegalization period. The increase in rate of persistent vomiting after policy implementation increased significantly (by about 8%), although there were no significant trends in increase prior to or during marijuana legalization in 2009. CONCLUSIONS: In an interrupted time series analysis of before, during, and after medical marijuana legalization, we estimated levels and rate changes in CDU and persistent vomiting. We found persistent increases in rates of CDU and persistent vomiting during and after legalization of marijuana.
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Canabinoides/efeitos adversos , Canabinoides/uso terapêutico , Política de Saúde , Uso da Maconha , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Hospitais , Humanos , Incidência , Análise de Séries Temporais Interrompida , Estados UnidosRESUMO
OBJECTIVE: Hospital palliative care has been shown to improve quality of life and optimize hospital utilization for seriously ill patients who need intensive care. The present review examined whether hospital palliative care in intensive care (ICU) and non-ICU settings will influence hospital length of stay and in-hospital mortality. METHOD: A systematic search of CINAHL/EBSCO, the Cochrane Library, Google Scholar, MEDLINE/Ovid, PubMed, and the Web of Science through 12 October 2016 identified 16 studies that examined the effects of hospital palliative care and reported on hospital length of stay and in-hospital death. Random-effects pooled odds ratios and mean differences with corresponding 95% confidence intervals were estimated. Heterogeneity was measured by the I 2 test. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system was utilized to assess the overall quality of the evidence. RESULTS: Of the reviewed 932 articles found in our search, we reviewed the full text of 76 eligible articles and excluded 60 of those, which resulted in a final total of 16 studies for analysis. Five studies were duplicated with regard to outcomes. A total of 18,330 and 9,452 patients were analyzed for hospital length of stay and in-hospital mortality from 11 and 10 studies, respectively. Hospital palliative care increased mean hospital length of stay by 0.19 days (pooled mean difference = 0.19; 95% confidence interval [CI 95%] = -2.22-2.61 days; p = 0.87; I 2 = 95.88%) and reduced in-hospital mortality by 34% (pooled odds ratio = 0.66; CI 95% = 0.52-0.84; p < 0.01; I 2 = 48.82%). The overall quality of evidence for both hospital length of stay and in-hospital mortality was rated as very low and low, respectively. SIGNIFICANCE OF RESULTS: Hospital palliative care was associated with a 34% reduction of in-hospital mortality but had no correlation with hospital length of stay.
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Mortalidade Hospitalar , Tempo de Internação/tendências , Cuidados Paliativos/normas , Humanos , Unidades de Terapia Intensiva/organização & administração , Cuidados Paliativos/tendênciasRESUMO
exo-Brevicomin (exo-7-ethyl-5-methyl-6,8-dioxabicyclo[3.2.1]octane) is an important semiochemical for a number of beetle species, including the highly destructive mountain pine beetle, Dendroctonus ponderosae. It also has been found in other insects and even in the African elephant. Despite its significance, little is known about its biosynthesis. In order to fill this gap and to identify new molecular targets for potential pest management methods, we performed gas chromatography-mass spectrometry analyses of cell cultures and in vitro assays of various D. ponderosae tissues with exo-brevicomin intermediates, analogs, and inhibitors. We confirmed that exo-brevicomin was synthesized by "unfed" males after emerging from the brood tree. Furthermore, in contrast to the paradigm established for biosynthesis of monoterpenoid pheromone components in bark beetles, exo-brevicomin was produced in the fat body, and not in the anterior midgut. The first committed step involves decarboxylation or decarbonylation of ω-3-decenoic acid, which is derived from a longer-chain precursor via ß-oxidation, to (Z)-6-nonen-2-ol. This secondary alcohol is converted to the known precursor, (Z)-6-nonen-2-one, and further epoxidized by a cytochrome P450 to 6,7-epoxynonan-2-one. The keto-epoxide is stable at physiological pH, suggesting that its final cyclization to form exo-brevicomin is enzyme-catalyzed. exo-Brevicomin production is unusual in that tissue not derived from ectoderm apparently is involved.
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Compostos Bicíclicos Heterocíclicos com Pontes/metabolismo , Besouros/metabolismo , Corpo Adiposo/metabolismo , Feromônios/metabolismo , Animais , Compostos Bicíclicos Heterocíclicos com Pontes/análise , Besouros/química , Corpo Adiposo/química , Feminino , Cetonas/análise , Cetonas/metabolismo , Masculino , Feromônios/análiseAssuntos
Cirrose Hepática , Readmissão do Paciente , Humanos , Medicaid , Medicare , Alta do Paciente , Estados UnidosAssuntos
Cryptococcus neoformans/isolamento & purificação , Meningite Criptocócica/diagnóstico , Adolescente , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Diagnóstico Diferencial , Flucitosina/uso terapêutico , Cefaleia/etiologia , Humanos , Masculino , Meningite Criptocócica/tratamento farmacológico , Debilidade Muscular/etiologiaRESUMO
Selenium, a trace element associated with memory impairment and glucose metabolism, mainly exerts its function through selenoproteins. SELENOM is a selenoprotein located in the endoplasmic reticulum (ER) lumen. Our study demonstrates for the first time that SELENOM knockout decreases synaptic plasticity and causes memory impairment in 10-month-old mice. In addition, SELENOM knockout causes hyperglycaemia and disturbs glucose metabolism, which is essential for synapse formation and transmission in the brain. Further research reveals that SELENOM knockout leads to inhibition of the brain insulin signaling pathway [phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR/p70 S6 kinase pathway], which may impair synaptic plasticity in mice. High-fat diet (HFD) feeding suppresses the brain insulin signaling pathway in SELENOM knockout mice and leads to earlier onset of cognitive impairment at 5 months of age. In general, our study demonstrates that SELENOM knockout induces synaptic deficits via the brain insulin signaling pathway, thus leading to cognitive dysfunction in mice. These data strongly suggest that SELENOM plays a vital role in brain glucose metabolism and contributes substantially to synaptic plasticity.
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Disfunção Cognitiva , Glucose , Animais , Camundongos , Encéfalo/metabolismo , Disfunção Cognitiva/genética , Disfunção Cognitiva/metabolismo , Dieta Hiperlipídica , Glucose/metabolismo , Insulina/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfatidilinositol 3-Quinases/metabolismo , Selenoproteínas/metabolismoAssuntos
Antivirais , Coinfecção , Hepatite C Crônica , Hepatite C , Transplante de Fígado , Análise Custo-Benefício , HIV , Hepacivirus , Custos Hospitalares , HumanosAssuntos
Antivirais , Hepatite C Crônica , Hepatite C , Genótipo , Hepacivirus , Humanos , Estados UnidosAssuntos
Antivirais , Hepatite C Crônica , Hepatite C , Análise Custo-Benefício , Hepacivirus , Humanos , MedicaidRESUMO
Heart failure (HF) remains the most common diagnosis of hospital admission among U.S. adults. Although diagnosis and treatment have improved, mortality rates have not changed, and mortality risk remains high after hospitalization. The current researchers examined how limited health literacy is associated with mortality risk in adults with recent hospitalization due to decompensated HF. Researchers conducted a systematic literature search, selecting three cohort and three intervention studies. The fixed-effect model was used. From the three cohort studies, 2,858 study participants were analyzed. Among participants, limited health literacy was associated with higher all-cause mortality (pooled odds ratio = 2.95; 95% confidence interval [2.34, 3.72]; p < 0.01; I2 = 47.38%). However, none of the intervention studies showed an association between limited health literacy and cardiac (or all-cause) mortality. Future research should focus on the efficiency and safety of telehealth-based medicine in patients with HF, particularly those with limited health literacy. [Res Gerontol Nurs. 2019; 12(2):91-108.].
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Letramento em Saúde , Insuficiência Cardíaca/mortalidade , Hospitalização , Humanos , Qualidade de Vida , TelemedicinaRESUMO
AIM: Pancreas cancer continues to carry a poor prognosis. Hospitalized patients with advanced chronic pancreatic illnesses increasingly receive palliative care due to its perceived clinical benefits. Meanwhile, a growing proportion of elderly patients are reportedly receiving life-sustaining procedures. Temporal trends in the utilization of life-sustaining procedures and palliative care consultation among dying patients with advanced chronic pancreatic illnesses in US hospitals were examined. METHODS AND MATERIALS: A serial, cross-sectional analysis was carried out using the National Inpatient Sample Database. Decedents 18 years and older with a principal diagnosis of pancreas cancer or other advanced chronic pancreatic illnesses from 2005 through 2014. The compound annual growth rates (CAGRs) and Cochrane-Armitage correction of χ2 statistic were used. The receipt of life-sustaining systemic procedures, intra-abdominal local procedures and surgeries, and palliative care consultation were examined. Multilevel multivariate logistic regressions were performed to examine the association of various procedures with the utilization of palliative care consultation. RESULTS: Among 77 394 183 hospitalizations, 29 515 patients were examined. The CAGRs of systemic procedures, intra-abdominal procedures, surgeries, and palliative care were -4.19% (P = .008), 2.17%, -1.40%, and 14.03% (P < .001), respectively. The receipt of systemic procedures (odds ratio [OR] = 2.40, 95% confidence interval [CI], 2.08-2.74), local intra-abdominal procedures (OR = 1.46, 95% CI, 1.27-1.70), and surgeries (OR = 2.51, 95% CI, 2.07-3.05) was associated with palliative care consultation (Ps < .001). CONCLUSIONS: Among adults with pancreatic cancer or other advanced chronic pancreatic illnesses in the US hospitals from 2005 to 2014, the utilization of life-sustaining systemic procedures decreased while the prevalence of palliative care consultation increased.