RESUMO
Reactive oxygen species (ROS) are produced during oxidative metabolism in aerobic organisms. Under normal conditions, ROS production and elimination are in a relatively balanced state. However, under internal or external environmental stress, such as high glucose levels or UV radiation, ROS production can increase significantly, leading to oxidative stress. Excess ROS production not only damages biomolecules but is also closely associated with the pathogenesis of many diseases, such as skin photoaging, diabetes, and cancer. Antioxidant peptides (AOPs) are naturally occurring or artificially designed peptides that can reduce the levels of ROS and other pro-oxidants, thus showing great potential in the treatment of oxidative stress-related diseases. In this review, we discussed ROS production and its role in inducing oxidative stress-related diseases in humans. Additionally, we discussed the sources, mechanism of action, and evaluation methods of AOPs and provided directions for future studies on AOPs.
Assuntos
Antioxidantes , Estresse Oxidativo , Humanos , Antioxidantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico , OxirreduçãoRESUMO
Indoor temperature has a critical impact on the performance of office workers. This study aimed to evaluate the effect of indoor temperature on work performance through subjective assessments, neurobehavioral tests, and physiological measurements. The experiment was conducted in a controlled office environment. Under each temperature condition, participants voted on their perception of thermal sensation, thermal satisfaction, and sick building syndrome (SBS) symptoms. Participants were given neurobehavioral tests based on a ten-item task, and their body temperature, blood pressure, heart rate, and blood oxygen saturation were measured before and after the tests. The study showed that the effect of indoor temperature on the test tasks varied greatly and depended on the task type. The indoor temperature, thermal sensation votes, and body temperature for optimum work performance were 17 °C, -0.57, and 36.4 °C, respectively. Work performance was positively correlated with thermal satisfaction votes and negatively correlated with sleepiness intensity.Practitioner summary: Work performance is closely related to indoor temperature. This study evaluated the effect of indoor temperature on work performance through subjective assessments, neurobehavioral tests, and physiological measurements. The relationships between work performance and indoor temperature, perceived votes, and physiological parameters were established, respectively.
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Poluição do Ar em Ambientes Fechados , Síndrome do Edifício Doente , Desempenho Profissional , Humanos , Temperatura , Poluição do Ar em Ambientes Fechados/análise , Ambiente ControladoRESUMO
Antimicrobial peptides (AMPs), also known as host defense peptides (HDPs), are important effector immune defense molecules in multicellular organisms. AMPs exert their antimicrobial activities through several mechanisms; thus far, induction of drug resistance through AMPs has been regarded as unlikely. Therefore, they have great potential as new generation antimicrobial agents. To date, more than 30 AMP-related drugs are in the clinical trial phase. In recent years, studies show that some AMPs and conventional antibiotics have synergistic effects. The combined use of AMPs and antibiotics can kill drug-resistant pathogens, prevent drug resistance, and significantly improve the therapeutic effects of antibiotics. In this review, we discuss the progress in synergistic studies on AMPs and conventional antibiotics. An overview of the current understanding of the functional scope of AMPs, ongoing clinical trials, and challenges in the development processes are also presented.
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Antibacterianos , Anti-Infecciosos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Peptídeos Antimicrobianos , HumanosRESUMO
BACKGROUND AND GOALS: Several studies have demonstrated that sorafenib is effective in the treatment of unresectable hepatocellular carcinoma (HCC). We performed a systematic review of the efficacy and safety of sorafenib in Child-Pugh A patients with unresectable HCC. The value of sorafenib treatment in different subgroups was examined. MATERIALS AND METHODS: A search of the literature published up to July 2012 was conducted. Pubmed, Embase, and the Cochrane library were searched and only randomized controlled trials were included. RESULTS: Five randomized controlled trials consisting of 1462 patients with unresectable HCC were included. Meta-analyses demonstrated that sorafenib improved the control rate of the disease [relative risk, 1.85; 95% confidence interval (CI), 1.55, 2.20; P<0.001], decreased the risk for tumor progression (hazard ratios, 0.61; 95% CI, 0.51, 0.73; P<0.001), and decreased mortality (hazard ratios, 0.71; 95% CI, 0.56, 0.89; P<0.001), relative to placebo. Subgroup analyses indicated that sorafenib-based treatments were effective in unresectable HCC regardless of the etiology, performance status, Barcelona Clinic Liver Cancer-stage, alanine transaminase/asparate transaminase, bilirubin, and α-feto protein level, except in the subgroup of prior local therapy. Sorafenib was associated with a higher risk of adverse effects than placebo. The risk for grade 3-4 hand-foot skin reactions, rash or desquamation, diarrhea, and hypertension was much higher in the sorafenib treatment group. These side effects could often be mitigated with appropriate treatment. CONCLUSIONS: Sorafenib was a moderately effective and safe oral drug for use in Child-Pugh A patients with unresectable HCC. Sorafenib monotherapy is not recommended for treating intermediate-stage HCC. More research is needed on the efficacy of sorafenib treatment in patients with prior local therapy.
Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia/uso terapêutico , Administração Oral , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/patologia , Progressão da Doença , Humanos , Neoplasias Hepáticas/patologia , Estadiamento de Neoplasias , Niacinamida/administração & dosagem , Niacinamida/efeitos adversos , Niacinamida/uso terapêutico , Compostos de Fenilureia/administração & dosagem , Compostos de Fenilureia/efeitos adversos , Modelos de Riscos Proporcionais , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , SorafenibeRESUMO
Cables are the main load-bearing components of a cable bridge and typically composed of high strength steel wires with a galvanized coating or Galfan coating. Galfan steel wire has recently started to be widely used because of its better corrosion resistance than galvanized steel wire. The corrosion characteristics of the coating and the difference in the corrosion fatigue process of the two types of steel wire are unclear. To further improve the service performance and maintenance of cable bridges, this study investigated the corrosion characteristics of galvanized steel wire and Galfan steel wire through accelerated corrosion tests and established a time-varying model of uniform corrosion and pitting corrosion of high-strength steel wire. Then, a long-span suspension bridge was taken as the research object, and the corrosion fatigue degradation of the two kinds of steel wire under a traffic load was analyzed on the basis of traffic monitoring data. The results showed that the uniform corrosion of the two types of steel wire conformed to an exponential development trend, the corrosion coefficient of galvanized steel wire conformed to the normal distribution, and the corrosion coefficient of Galfan steel wire conformed to the Cauchy distribution. The maximum pitting coefficient distribution of the two kinds of steel wire conformed to the generalized extreme value distribution. The location parameters and scale parameters of the two distributions showed an exponential downward trend with the increase of corrosion duration. When the traffic intensity was low, the corrosion characteristics of the steel wire was the main factor affecting its service life, and the average service life of Galfan steel wire was significantly higher than that of galvanized steel wire. Under a dense traffic flow, the service life of the steel wire was mainly controlled by the traffic load, and the service life of Galfan steel wire was slightly improved. Effective anti-corrosion measures are a key factor for improving the service life of steel wire.
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BACKGROUND: Sepsis is a common disease in the intensive care unit, accompanied by many complications and high mortality. Organ dysfunction is a major risk factor for death in patients with sepsis. Analyzing the related factors of organ dysfunction caused by sepsis can provide more clinical prevention and treatment targets, and better predict patients' prognoses. This study aimed to investigate the relationship between blood pressure variability (BPV) and organ dysfunction in patients with sepsis. METHODS: One hundred and two patients with sepsis treated in our hospital from January 2019 to January 2021 were retrospectively collected as an observation group, and 102 healthy people were collected as a control group. The 24-hour systolic blood pressure variability (24h SBPV) and 24-hour diastolic blood pressure variability (24h DBPV) of the two groups were compared, and the correlation between 24h SBPV, 24h DBPV, and organ function damage to sepsis patients were analyzed. RESULTS: Compared with the control group, the 24h DBPV in the observation group was significantly higher (0.56±0.16 vs. 0.37±0.16, P=0.000). 24h SBPV increased significantly (0.56±0.16 vs. 0.36±0.17, P=0.000). Pearson linear correlation analysis showed 24h SBPV was positively correlated with the level of procalcitonin, APACHEII score, and SOFA score (r=0.301, 0.216 and 0.218, P<0.05). 24h DBPV was positively correlated with the level of procalcitonin, APACHEII score, and SOFA score (r=0.302, 0.212 and 0.210, P<0.05). 24h SBPV and 24h DBPV are of certain value in the diagnosis of multiple organ failure in patients with sepsis, and the area under the curve was [0.649 (95% CI: 0.539-0.759), P=0.010] and [0.650 (0.540-0.760), P=0.009], respectively. 24h SBPV and 24h DBPV are of certain value in the diagnosis of persistent organ failure in patients with sepsis, and the area under the curve was [0.647 (95% CI: 0.538-0.757), P=0.010] and [0.647 (95% CI: 0.538-0.757), P=0.010], respectively. CONCLUSIONS: The increase of BPV in patients with sepsis has a certain value in predicting the prognosis and organ function damage to patients with sepsis.
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Insuficiência de Múltiplos Órgãos , Sepse , Pressão Sanguínea , Humanos , Unidades de Terapia Intensiva , Insuficiência de Múltiplos Órgãos/etiologia , Estudos RetrospectivosRESUMO
Self-compacting lightweight concrete (SCLC) is a promising construction material for building applications, but most SCLCs today are made with river sand (RS). There is an increasing demand for environmental protection, as well as materials with a high strength/density ratio. The manufactured sand (MS) and lightweight sand (LS) as fine aggregates in cement-based composite materials have been receiving more attention among researchers. However, there is not much information about the effects of MS and LS on the properties of the fresh and hardened SCLCs. In this paper, the properties of fresh and hardened SCLC made with MS and LS were investigated by a series of experiments. SCLCs made with RS served as the control in this study. The test results show that increasing the sand ratio (from 0.40-0.50) decreased the filling ability and led to an increased T50 time, which is the time spent for the concrete to reach the 500 mm spread circle, for all of the fresh SCLCs. Although the passing ability of MS-SCLCs and LS-SCLCs is not as good as RS-SCLCs, their results are still within an acceptable range. The ratio of mechanical properties to density was found to increase with an increase of the sand ratio for all of the hardened SCLCs. MS-SCLCs presented the highest compressive strength among all of the SCLCs studied. Although the mean compressive strength of LS-SCLCs is lower than those of the other two SCLCs by 8%, their strength to density ratio is higher than others by 15%, and the ratio increases remarkably with the increase of the sand ratio. Permeability test results showed that the permeability coefficient of MS-SCLC is remarkably lower than that of LS-SCLC, but slightly higher than that of RS-SCLC.
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Engineers can learn from nature for inspirations to create new designs. The internal structure of lotus roots with several oval holes was studied in this paper for engineering inspirations. The structural performance of lotus roots under outside water pressure was simulated and compared with various cross-sectional areas. The distribution of stresses in the cross-sectional area of lotus roots was analysed and presented. It was found that the maximum compressive stresses in the cross-sectional area of lotus roots were occurring at the long axis ends of the holes. This was very different from that of circular holes. Further analysis on the triaxiality factors revealed that the cross-sectional area of the lotus root resulted in large areas of high triaxiality factors. The resulting hydrostatic stress in the cross-sectional area of lotus root ranges from zero to 2.7 times the applied outside pressure. In contrast, the hydrostatic stress in a cylindrical cross-sectional area is a fixed value. The study showed that the lotus root and the orientation of the oval holes could be mimicked in the design of new structures, for example, underwater pipes and vessels.