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OBJECTIVE: To find efficient cuproptosis-related biomarkers to explore the oncogenesis and progression of oral squamous cell carcinoma (OSCC). METHODS: All the original data were downloaded from the Cancer Genome Atlas (TCGA) database. Univariate Cox analysis and Kaplan-Meier survival analysis were used to identify the gene related to survival. Tumor Immune Estimation Resource 2.0 (TIMER 2.0) was used to reveal the different expression of cuproptosis-related gene lipoyltransferase 1 (LIPT1) in various kinds of tumours. RESULTS: LIPT1, as a cuproptosis-related gene, was found to be differentially expressed in the OSCC group and the control group. It was also found to be related to the prognosis of OSCC. Pan cancer analysis showed LIPT1 was also involved in various kinds of tumours. CONCLUSION: All the results demonstrate that the cuproptosis-related gene LIPT1 is highly involved in the oncogenesis and progression of OSCC. These findings give new insight for further research into the cuproptosis-related biomarkers in OSCC.
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Biomarcadores Tumorais , Carcinoma de Células Escamosas , Neoplasias Bucais , Humanos , Neoplasias Bucais/genética , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Prognóstico , Aciltransferases/genética , Estimativa de Kaplan-MeierRESUMO
Repetitive overhead tasks during factory work can cause shoulder injuries resulting in impaired health and productivity loss. Soft wearable upper extremity robots have the potential to be effective injury prevention tools with minimal restrictions using soft materials and active controls. We present the design and evaluation of a portable inflatable shoulder wearable robot for assisting industrial workers during shoulder-elevated tasks. The robot is worn like a shirt with integrated textile pneumatic actuators, inertial measurement units, and a portable actuation unit. It can provide up to 6.6 newton-meters of torque to support the shoulder and cycle assistance on and off at six times per minute. From human participant evaluations during simulated industrial tasks, the robot reduced agonist muscle activities (anterior, middle, and posterior deltoids and biceps brachii) by up to 40% with slight changes in joint angles of less than 7% range of motion while not increasing antagonistic muscle activity (latissimus dorsi) in current sample size. Comparison of controller parameters further highlighted that higher assistance magnitude and earlier assistance timing resulted in statistically significant muscle activity reductions. During a task circuit with dynamic transitions among the tasks, the kinematics-based controller of the robot showed robustness to misinflations (96% true negative rate and 91% true positive rate), indicating minimal disturbances to the user when assistance was not required. A preliminary evaluation of a pressure modulation profile also highlighted a trade-off between user perception and hardware demands. Finally, five automotive factory workers used the robot in a pilot manufacturing area and provided feedback.
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Desenho de Equipamento , Amplitude de Movimento Articular , Robótica , Ombro , Torque , Dispositivos Eletrônicos Vestíveis , Humanos , Robótica/instrumentação , Fenômenos Biomecânicos , Masculino , Ombro/fisiologia , Adulto , Amplitude de Movimento Articular/fisiologia , Músculo Esquelético/fisiologia , Eletromiografia/instrumentação , Indústrias/instrumentação , Lesões do Ombro/prevenção & controle , Feminino , Adulto Jovem , Análise e Desempenho de Tarefas , Articulação do Ombro/fisiologia , Exoesqueleto EnergizadoRESUMO
Magnesium matrix composites are essential lightweight metal matrix composites, following aluminum matrix composites, with outstanding application prospects in automotive, aerospace lightweight and biomedical materials because of their high specific strength, low density and specific stiffness, good casting performance and rich resources. However, the inherent low plasticity and poor fatigue resistance of magnesium hamper its further application to a certain extent. Many researchers have tried many strengthening methods to improve the properties of magnesium alloys, while the relationship between wear resistance and plasticity still needs to be further improved. The nanoparticles added exhibit a good strengthening effect, especially the ceramic nanoparticles. Nanoparticle-reinforced magnesium matrix composites not only exhibit a high impact toughness, but also maintain the high strength and wear resistance of ceramic materials, effectively balancing the restriction between the strength and toughness. Therefore, this work aims to provide a review of the state of the art of research on the matrix, reinforcement, design, properties and potential applications of nano-reinforced phase-reinforced magnesium matrix composites (especially ceramic nanoparticle-reinforced ones). The conventional and potential matrices for the fabrication of magnesium matrix composites are introduced. The classification and influence of ceramic reinforcements are assessed, and the factors influencing interface bonding strength between reinforcements and matrix, regulation and design, performance and application are analyzed. Finally, the scope of future research in this field is discussed.
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T-2 toxin is a mycotoxin with multiple toxic effects and has emerged as an important food pollutant. Microglia play a significant role in the toxicity of various neurotoxins. However, whether they participate in the neurotoxicity of T-2 toxin has not been reported. To clarify this point, an in vivo mouse model of T-2 toxin (4 mg/kg) poisoning was established. The results of Morris water maze and open-field showed that T-2 toxin induced learning and memory impairment and locomotor inhibition. Meanwhile, T-2 toxin induced microglial activation, while inhibiting microglia activation by minocycline (50 mg/kg) suppressed the toxic effect of the T-2 toxin. To further unveil the potential mechanisms involved in T-2 toxin-induced microglial activation, an in vitro model of T-2 toxin (0, 2.5, 5, 10 ng/mL) poisoning was established using BV-2 cells. Transcriptomic sequencing revealed lots of differentially expressed genes related to MAPK/NF-κB pathway. Western blotting results further confirmed that T-2 toxin (5 ng/mL) induced the activation of MAPKs and their downstream NF-κB. Moreover, the addition of inhibitors of NF-κB and MAPKs reversed the microglial activation induced by T-2 toxin. Overall, microglial activation may contribute a considerable role in T-2 toxin-induced behavioral abnormalities, which could be MAPK/NF-κB pathway dependent.
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NF-kappa B , Toxina T-2 , Camundongos , Animais , NF-kappa B/metabolismo , Microglia , Toxina T-2/metabolismo , Transdução de Sinais , Regulação da Expressão Gênica , Lipopolissacarídeos/farmacologiaRESUMO
Evidence of the short-term effects of ambient sulfur dioxide (SO2) exposure on the economic burden of ischemic stroke is limited. This study aimed to explore the association between short-term ambient SO2 exposure and hospitalization costs for ischemic stroke in Chongqing, the most populous city in China. The hospital-based study included 7271 ischemic stroke inpatients. Multiple linear regression models were used to estimate the association between SO2 concentration and hospitalization costs. Propensity score matching was used to compare the patients' characteristics when exposed to SO2 concentrations above and below 20 µg/m3. It is found that short-term SO2 exposure was positively correlated with the hospitalization costs of ischemic stroke. The association was more evident in males, people younger than 65, and people hospitalized in the cool seasons. Besides, among the components of hospitalization costs, medicine costs were most significantly associated with SO2. More interesting, the lower concentration of SO2, the higher costs associated with 1 µg/m3 SO2 change. Above all, SO2 was positively associated with hospitalization costs of ischemic stroke, even at its low levels. The measures to reduce the level of SO2 can help reduce the burden of ischemic stroke.
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Poluentes Atmosféricos , Poluição do Ar , AVC Isquêmico , Masculino , Humanos , Poluentes Atmosféricos/análise , Dióxido de Enxofre/análise , Poluição do Ar/análise , Material Particulado/análise , Exposição Ambiental/análise , Hospitalização , China , Hospitais , Dióxido de NitrogênioRESUMO
Previous researches have reported the association between air pollution and various diseases. However, few researches have investigated whether air pollutants are associated with the economic loss resulting from patients' hospitalization, especially the economic loss of hospitalization due to acute cardiovascular events. The purpose of our research was to explore the association between the levels of carbon monoxide (CO), taken as an index of pollution, and the hospitalization costs of myocardial infarction (MI), and the potential effect modification by the ABO blood group. A total of 3237 MI inpatients were included in this study. A multiple linear regression model was used to evaluate the association between ambient CO levels and hospitalization costs of MI patients. Moreover, we performed stratified analyses by age, gender, body mass index (BMI), season, hypertension, and ABO blood types. There was a positive association between the levels of CO in the air and the costs of hospitalization caused by MI. Furthermore, such association was stronger in males, BMI ≥25, <65 years, with hypertension, and non-O blood group. Interestingly, we found the association was particularly significant in patients with blood group B. Overall, our study first found that ambient CO levels could have an impact on the hospitalization costs for MI patients, and those with blood group B can be more sensitive.
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Poluentes Atmosféricos , Poluição do Ar , Hipertensão , Infarto do Miocárdio , Masculino , Humanos , Monóxido de Carbono/análise , Sistema ABO de Grupos Sanguíneos/análise , Poluição do Ar/análise , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Hospitalização , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/induzido quimicamente , Hipertensão/induzido quimicamenteRESUMO
Type 2 diabetes (T2DM) as a non-communicable disease imposes heavy disease burdens on society. Limited studies have been conducted to assess the effects of short-term air pollution exposure on T2DM, especially in Asian regions. Our research aimed to determine the association between short-term exposure to ambient nitrogen dioxide (NO2) and outpatient visits for T2DM in Chongqing, the largest city in western China, based on the data collected from November 28, 2013 to December 31, 2019. A generalized additive model (GAM) was applied, and stratified analyses were performed to investigate the potential modifying effects by age, gender, and season. Meanwhile, the disease burden was revealed from attributable risk. Positive associations between short-term NO2 and daily T2DM outpatient visits were observed. The strongest association was observed at lag 04, with per 10 µg/m3 increase of NO2 corresponded to increased T2DM outpatient visits at 1.57% [95% confidence interval (CI): 0.48%, 2.65%]. Stronger associations were presented in middle-aged group (35-64 years old), male group, and cool seasons (October to March). Moreover, there were 1.553% (8664.535 cases) of T2DM outpatient visits attributable to NO2. Middle-aged adults, males, and patients who visited in cool seasons suffered heavier burdens. Conclusively, short-term exposure to NO2 was associated with increased outpatient visits for T2DM. Attention should be paid to the impact of NO2 on the burden of T2DM, especially for those vulnerable groups.
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Poluentes Atmosféricos , Poluição do Ar , Diabetes Mellitus Tipo 2 , Adulto , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , China/epidemiologia , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/epidemiologia , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Dióxido de Nitrogênio/análise , Dióxido de Nitrogênio/toxicidade , Pacientes Ambulatoriais , Material Particulado/análise , Material Particulado/toxicidadeRESUMO
Atrial fibrillation (AF) is the most common sustained heart rhythm disorder associated with high mortality and morbidity. Limited studies have been conducted to assess the relationship between short-term exposure to ambient air pollution and AF attacks. This study aimed to explore the association between short-term ambient nitrogen dioxide (NO2) exposure and outpatient visits for AF in Xi'an, China. Data on daily AF outpatient visits and air pollutants from 2013 to 2019 (2555 days) were obtained. A time-series approach using over-dispersed Poisson generalized additive model (GAM) was employed, and stratified analyses were performed to investigate the potential modifying effects by season, age, and gender. A total of 8307 outpatient visits for AF were recorded. Increased levels of NO2 were associated with increased AF outpatient visits, and the most significant effect estimates were observed at lag 03: A 10 µg/m3 increase of NO2 at lag 03 was related to an elevation of 5.59% (95% CI: 2.67%, 8.51%) in daily outpatient visits for AF. Stratified analyses showed that there were no gender and age difference in the effect of NO2, while more obvious association was observed in cool seasons (October to March) than in warm seasons (April to September). In summary, short-term ambient NO2 exposure can be positively associated with daily outpatient visits for AF, especially in cool seasons. This work provided novel data that the association between air pollutants and AF can vary by seasons, further supporting that the prevention of cardiovascular health effects should be strengthened in winter.
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Poluentes Atmosféricos , Poluição do Ar , Fibrilação Atrial , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Fibrilação Atrial/induzido quimicamente , Fibrilação Atrial/epidemiologia , China/epidemiologia , Hospitais , Humanos , Dióxido de Nitrogênio/análise , Pacientes Ambulatoriais , Material Particulado/análise , Estações do AnoRESUMO
Sleep disorders attract increasing concerns. However, the evidence of the association between ambient air pollution and sleep disorders is limited. Therefore, our aim was to determine the association between short-term air pollution exposure and outpatient visits for sleep disorders in Xi'an, the largest city in Northwest China. Baseline outpatient data of daily sleep disorders between 2011 and 2013 were collected. Quasi-Poisson distribution was applied by adjusting the day of the week and weather conditions. A total of 49,282 sleep disorder outpatient visits were recorded. The most significant association between air pollutants and outpatient visits was observed on concurrent day: per 10 µg/m3 increase of NO2, SO2, and PM10 at lag 0 corresponded to increased outpatient sleep disorder visits at 0.22% (95% CI: 0.03%, 0.42%), 1.53% (95% CI: 0.53, 2.53%), and 2.57% (95% CI: 1.33%, 3.82%), respectively. As for gender-specific analysis, there was no statistically significant difference between males and females. The result of season-specific analysis showed no statistically significant difference between warm seasons and cool seasons, either. As for age-specific analysis, obvious associations were observed in 20-40 age group (NO2) and > 40 age group (PM10 and SO2), while no evident association was found for the young age group (< 20 years old). Conclusively, short-term exposure to air pollutants, especially gaseous air pollutants, might increase the risk of sleep disorders, and such association appears to be more obvious in elder people. We provide novel data that there may be age differences in the relationship between short-term air pollution exposure and sleep disorders.
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Poluentes Atmosféricos , Poluição do Ar , Transtornos do Sono-Vigília , Adulto , Idoso , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China/epidemiologia , Feminino , Humanos , Masculino , Dióxido de Nitrogênio/análise , Pacientes Ambulatoriais , Material Particulado/análise , Transtornos do Sono-Vigília/epidemiologia , Adulto JovemRESUMO
Many researches have reported the air pollution impacts, either long term or short term, on inflammatory skin diseases, but there are few studies on the relation between PM2.5 and acne vulgaris. To determine the correlation between short-term PM2.5 exposure and acne outpatient visits, data for 120,842 acne vulgaris outpatient visits between December 2013 and December 2019 were obtained from three large hospitals in Chongqing, China. Both single-pollutant models and two-pollutant models were established to explore the relationship between PM2.5 exposure and acne outpatient visits. The stratified analyses were conducted through two-sample z-tests to investigate the possible gender (male or female) and age (< 25 years or ≥ 25 years) differences in PM2.5 effects. The results demonstrated positive correlations between PM2.5 concentrations and acne outpatient visits. A 10 µg/m3 increase in PM2.5 concentration was associated with a 1.71% (95% CI: 1.06-2.36%) increase in acne outpatient visits at lag 0-7 day. Stratified analyses showed that PM2.5 effects were greater in individuals aged ≥ 25 years than those aged < 25 years, but no gender difference was found. In conclusion, short-term PM2.5 exposure was positively associated with the risk of acne outpatient visits, especially for people ≥ 25 years old.
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Acne Vulgar , Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Acne Vulgar/epidemiologia , Adulto , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China/epidemiologia , Exposição Ambiental/análise , Poluentes Ambientais/análise , Feminino , Humanos , Masculino , Pacientes Ambulatoriais , Material Particulado/análiseRESUMO
Ambient carbon monoxide (CO) is associated with bronchitis morbidity, but there is no evidence concerning its correlation with hospitalization costs for bronchitis patients. This study aimed to investigate the relationship between short-term ambient CO exposure and hospitalization costs for bronchitis patients in Chongqing, China. Baseline data for 3162 hospitalized bronchitis patients from November 2013 to December 2019 were collected. Multiple linear regression analysis was used to determine the association, delayed and cumulative, between short-term CO exposure and hospitalization costs. Additionally, subgroup analyses were performed by gender, age, season, and comorbidity. Positive association between CO and hospitalization costs for bronchitis patients was observed. The strongest association was observed at lag 015 days, with per 1 mg/m3 increase of CO concentrations corresponded to 5834.40 Chinese Yuan (CNY) (95% CI: 2318.71, 9350.08; P < 0.001) (845.97 US dollars) increment in hospitalization costs. Stratified analysis results showed that the association was more obvious among those males, elderly, with comorbidities, and in warm seasons. More importantly, there was strongest correlation between CO and bronchitis patients with coronary heart disease. In summary, short-term exposure to ambient CO, even lower than Chinese and WHO standards, can be associated with increased hospitalization costs for bronchitis. Controlling CO exposure can be helpful to reduce medical burden associated with bronchitis patients. The results also suggest that when setting air quality standards and formulating preventive measures, susceptible subpopulations ought to be considered.
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Poluentes Atmosféricos , Poluição do Ar , Bronquite , Idoso , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/análise , Bronquite/epidemiologia , Monóxido de Carbono/análise , China/epidemiologia , Exposição Ambiental/análise , Hospitalização , Hospitais , Humanos , Masculino , Material Particulado/análiseRESUMO
Anxiety, a common and devastating mental disorder, has raised widespread interests. The impacts of air pollution on physical health are well known, whereas few studies have explored the association of atmospheric pollution, especially short-term air pollution exposure, with the risk of anxiety disorders. In addition, there are increasing concerns in emerging evidence supporting a possible etiological link. Therefore, our aim was to evaluate the relationship between short-term exposure to atmospheric pollutants and anxiety outpatient visits in Xi'an, a city of northwestern China and a metropolis with relatively heavy air pollution. We collected the data of both daily outpatient visits and daily air pollution (SO2, NO2, and PM10) between January 1, 2010 and January 31, 2016 (2222 days). To clarify the association between short-term ambient atmospheric pollution exposure and anxiety outpatient visits, an over-dispersed Poisson generalized additive model was applied by adjusting the day of the week and weather conditions (including temperature, humidity, sunlight hours, and rainfalls). Positive association between gaseous air pollutants (SO2 and NO2) and anxiety daily outpatient visits was observed. Moreover, the largest estimated values of both SO2 and NO2 were evidence at lag 03 (4-day moving average lag), with 10 µg/m3 increase corresponded to the increase of outpatient anxiety visits at 4.11% (95% CI: 2.15%, 6.06%) for SO2 and 3.97% (95% CI: 1.90%, 6.06%) for NO2. However, there was no differences in susceptibility to air pollutants between different genders as well as different ages. Taken together, short-term exposure to ambient air pollutants, especially gaseous air pollutants (NO2 and SO2), can be related to higher risk of anxiety outpatient visits.
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Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Ansiedade/induzido quimicamente , Ansiedade/epidemiologia , Transtornos de Ansiedade , China/epidemiologia , Cidades , Feminino , Hospitais , Humanos , Masculino , Pacientes Ambulatoriais , Material Particulado/análiseRESUMO
Depression is known to be one of the most common mental disorders raising global concerns. However, evidence regarding the association between short-term air pollution exposure and risk of development of depression is limited. The aim of this was to assess the relationship between short-term ambient air pollution exposure and depression in outpatient visits in Xi'an, a northwestern Chinese metropolis. Data for air pollutants including particulate matter (PM10), sulfur dioxide (SO2), and nitrogen dioxide (NO2) levels from October 1, 2010 to December 31, 2013 and number of daily depression outpatient visits (92,387 in total) were collected. A time-series quasi-Poisson regression model was adopted to determine the association between short-term air pollutant concentrations and frequency of outpatient visits for depression with different lag models. Consequently, 10 µg/m3 increase of SO2 and NO2 levels corresponded to significant elevation in number of outpatient-visits for depression on concurrent days (lag 0), and this relationship appeared stronger in cool seasons (October to March). However, the association of PM10 was only significant in males aged 30-50 at lag 0. Evidence indicated that short-term exposure to ambient air pollutants especially in cool seasons might be associated with increased risk of outpatient visits for depression.
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Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Depressão/epidemiologia , Dióxido de Nitrogênio/efeitos adversos , Pacientes Ambulatoriais/estatística & dados numéricos , Material Particulado/efeitos adversos , Dióxido de Enxofre/efeitos adversos , Adulto , Idoso , China , Depressão/psicologia , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estações do Ano , Adulto JovemRESUMO
People with tetraplegia resulting from spinal cord injury experience debilitating hand impairments that may lead to lifelong dependence on others to perform activities of daily living. Wearable robotic devices that actively support hand function during daily living tasks could bring great benefits to this population. In this work, the performance of a textile-based soft robotic glove controlled by the user with a button was evaluated in thirteen participants with tetraplegia. Performance outcomes included activities of daily living using the Jebsen Taylor Hand Function Test, active range of motion of the fingers, and grasp strength for power and pinch grasps. In the Jebsen Test, participants showed significant improvements in performance of activities of daily living with glove assistance, completing a median of 50% more tasks than in their baseline attempt without the glove. Significant improvements were also found for power and pinch grasp forces and active range of motion of the fingers with the glove assistance. Participants with lower baseline motor function received greater benefits from glove assistance. This work demonstrates the effectiveness of a user-controlled textile-based soft robotic glove to improve activity of daily living abilities in individuals with hand impairments resulting from spinal cord injury.
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Robótica , Traumatismos da Medula Espinal , Atividades Cotidianas , Mãos , Força da Mão , Humanos , Traumatismos da Medula Espinal/complicaçõesRESUMO
In the surface ehanced Raman scattering (SERS) technology, not only to improve the making process of SERS substrates, to be fast and easily, but also to enhance the SERS enhance factor, an easy replacement reaction between zinc and silver nitrate solution has been adopted to prepare silver micro-structures SERS-active substrate. The silver micro-substrates have many advantages. These substrates have good stability, well preservation, an easy making method and a fast making process. The surface profile of the silver microparticles is investigated by scanning electron microscope (SEM). The silver microstructures are dendritic shape in a symmetrical fashion with symmetrical distribution. When the time of the replace reaction is 40, 50 and 60 s, respectively, the average lengths of "trunks" in the silver dendritic microsubstractes are about 3, 5 and 10 µm, and the lengths of the "branches" are about 700 nm, 2 µm and 3 µm, respectively. The result shows that the longer time the replacement reaction takes, the longer lengths of the "trunks" and "branches" in the silver dendritic microsubstractes become. With the time of replace reaction increasing, the "trunk" and "branch" in the silver dendritic microsubstractes grow longer and a large amount of nano-level "leaves" grow out from the "branches" of the silver dendritic microsubstractes, so the silver micro size dendrates have nano level structure on surface. In order to investigate the SERS-active substrates application in SERS, a Fourier transform Raman spectrograph with a 1 064 nm laser wavelength is used to measure the SERS spectra. And good SERS spectra have been obtained by using dendritic silver microsubstrates on the silicon chip as a SERS substract, and Rhodamine 6G (R6G) as a molecule probe. It is found that the silver micro-substrates have good Raman characteristics. And comparing these SERS spectra, it gets the conclution that the spectra with best SERS enhance effect are obtained when R6G is obsorbed on the silver dendritic micro-substractes whose preparing time is 40s, and at that time, the analytical enhancement factor for SERS signals is approximately 10(3). And when the silicon ships are dealed with surfactants Polyvinylpyrrolidone (PVP) and keeping the other conditions the same as before, the SERS enhance effect of the spectra becomes better, and the enhancement factor turn to be approximately 10(4). What's more, the silver microstructures can be preserved several monthes under deionized water and the repeatment of the expriment result is well in general.
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As a large number of multidrug-resistant bacteria have emerged, and there is an urgent need for the development of new antibacterial agents. In this study, we developed a liquid-based slow killing assay to be carried out in standard 96-well microtiter plates. This screening method was designed to facilitate high-throughput screening of small molecules and extracts. In antibiotic rescue assays, the Caenorhabditis elegans multidrug-resistant Pseudomonas aeruginosa infection model displayed a high degree of drug resistance in vivo and in vitro. We used the method to screen 1,300 extracts, and found 36 extracts (2.7%) which prolonged the survival of infected nematodes, and four (0.3%) of these extracts showed in vitro and in vivo anti-multidrug resistant P. aeruginosa activity. These results indicate that the whole-animal C. elegans multidrug-resistant bacterial model can be used to screen antibacterial compounds, and can also be useful for bioactive compounds which most likely cannot be identified in vitro.
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Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Larva/crescimento & desenvolvimento , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Animais , Antibacterianos/química , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/microbiologia , Contagem de Colônia Microbiana , Larva/microbiologia , Extratos Vegetais/química , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/patogenicidade , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologiaRESUMO
Spinosyns A and D are novel macrolide secondary metabolites containing two deoxysugars. Each of the sugars is derived from a common intermediate, which is biosynthesized sequentially by NDP-glucose synthase and glucose dehydratase. Systematical duplication of gtt and gdh was carried out by genetic engineering in Saccharopolyspora spinosa. Introduction of additional gtt and gdh genes under the control of PermE* promoter showed significant increase on their transcript levels. The production of spinosad was increased by over threefold to reach 800 µg/ml in the recombinant strain SIPI-M2093.