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1.
ChemistryOpen ; : e202300217, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38441499

RESUMO

The increasing prevalence of wearable devices has sparked a growing interest in real-time health monitoring and physiological parameter tracking. This study focuses on the development of a cost-effective sweat analysis device, utilizing microfluidic technology and selective electrochemical electrodes for non-invasive monitoring of glucose and potassium ions. The device, through real-time monitoring of glucose and potassium ion levels in sweat during physical activity, issues a warning signal when reaching experimentally set thresholds (K+ concentration at 7.5 mM, glucose concentrations at 60 µM and 120 µM). This alerts users to potential dehydration and hypoglycemic conditions. Through the integration of microfluidic devices and precise electrochemical analysis techniques, the device enables accurate and real-time monitoring of glucose and potassium ions in sweat. This advancement in wearable technology holds significant potential for personalized health management and preventive care, promoting overall well-being, and optimizing performance during physical activities.

2.
Rev Sci Instrum ; 94(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37862520

RESUMO

Ultra-fast high-voltage switches (UFHVSs) are a core component of time-of-flight mass spectrometers for realizing high accuracy ion acceleration, deceleration, and temporal focusing. The desirable features of high performance UFHVSs include a large range of adjustability of pulse width, a high maximum output amplitude, and minute rising and falling times. Besides the simplicity of the driver circuit, the total cost of the whole device is also critical to its practical applications. In this work, we present a low-cost and easy-fabrication 5000 V bipolar solid-state UFHVS for a high-resolution mass spectrometer. A double-pulse transformer isolates the circuit's high- and low-voltage sides and synchronously drives series-connected cascode SiC FETs to form its push-pull topology. This scheme allows transmitting drive signals with long widths but without the magnetic saturation of the transformer. Testing results show that output pulses reach a maximum voltage of 5000 V and a width of 150 µs, with rising and falling times of 8.5 and 18.3 ns, respectively. More importantly, they have nearly no voltage decay.

3.
Heliyon ; 9(7): e17903, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37539201

RESUMO

The Yellow River Basin in China has the world's most serious soil erosion problem. The Yellow River Basin in Sichuan Province (YRS), as the upper reaches of the Yellow River, and its water conservation (WC) capacity greatly affects the ecological environment of the downstream basin. In recent years, YRS has received more and more attention, and numerous policies have been developed to improve local WC. However, there is a vacancy in the long-term research of WC in the YRS due to the lack of in-situ data. This study quantitatively evaluated the WC of YRS from 2001 to 2020 through Google Earth Engine (GEE) and analyzed the spatio-temporal variations of WC and land cover (LC). CA-Markov predicted the LC and WC in 2025 under three scenarios to assess the contribution of different scenarios to WC. The WC in YRS fluctuated from 1.93 to 6.77 billion m3. The climate is the dominant factor of WC change, but the effect of LC on WC is also evident. The WC capacity increases with vegetation coverage and height. The WC capacity of forests per km2 exceeds 600 mm, while that of grasslands is about 250 mm, and barren can cause around 300 mm of WC loss. In 2025, the WC in YRS may exceed 7.5 billion m3, but the past ecological management mode should be transformed. Improving the quality of land use and converting grasslands to forests is better than reducing cropland to improve WC.

4.
J Orthop Surg Res ; 18(1): 440, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37337281

RESUMO

OBJECTIVE: The purpose of this study was to quantify the degree of lumbar spinal stenosis by assessing the anterior and posterior vertebral canal diameter and dural area, determine the sensitivity of the anterior and posterior spinal canal diameter, dural area and dural occupying rate in predicting the postoperative efficacy of oblique lumbar interbody fusion (OLIF) for patients with single-stage lumbar spinal stenosis, and identify the corresponding indicators suggesting that OLIF surgery should not be performed. METHODS: In a retrospective analysis of patients who had previously undergone OLIF surgery in our hospital, we included a total of 104 patients with lumbar spinal stenosis who had previously undergone single-stage surgery in our hospital. Three independent observers were employed to measure the anterior and posterior diameter of the spinal canal (AD, mm), dural area (CSA, mm2), the spinal canal area (SCA, mm2), and the ratio of the dural area to the spinal canal area (DM, %) at the disc level with the most severe stenosis on MRI. According to the values of AD and CSA in preoperative MRI, patients were divided into three groups: A, B, and C (Group A: AD > 12 and 100 < CSA ≤ 130, group B: Except A and C, group C: AD ≤ 10 and CSA ≤ 75). Preoperative and postoperative clinical outcome scores (Japanese Orthopaedic Association [JOA] score, VAS score, modified Macnab standard) of 104 patients were statistically. RESULTS: There were significant differences in the preoperative and postoperative clinical correlation scores among the mild, moderate and severe lumbar spinal stenosis groups. The improvement rate of the post treatment JOA score, the difference between the preoperative and postoperative VAS score, and the modified Macnab standard were compared pairwise. There was no statistical significance in the improvement rate of the post treatment JOA score, the difference between the preoperative and postoperative VAS score, and the modified Macnab standard between Group A and Group B (P = 0.125, P = 0.620, P = 0.803). There were statistically significant differences between Group A and Group C and between Group B and Group C in the improvement rate of the JOA score, the difference in the pre- and postoperative VAS score, and the modified Macnab standard. The anterior and posterior vertebral canal diameter and dural area are sensitive predictors of the postoperative efficacy of OLIF surgery for single-stage lumbar spinal stenosis. Moreover, when the anterior and posterior vertebral canal diameter was less than 6.545 mm and the dural area was less than 34.43 mm2, the postoperative effect of OLIF surgery was poor. CONCLUSIONS: All the patients with mild, moderate, and severe lumbar spinal stenosis achieved curative effects after OLIF surgery. Patients with mild and moderate lumbar spinal stenosis had better curative effects, and there was no significant difference between them, while patients with severe lumbar spinal stenosis had poor curative effects. Both the anteroposterior diameter of the spinal canal and the dural area of the spinal canal were sensitive in predicting the curative effect of OLIF surgery for single-stage lumbar spinal stenosis. When the anterior and posterior vertebral canal diameter was less than 6.545 mm and the dural area was less than 34.43 mm2, the postoperative effect of OLIF surgery was poor.


Assuntos
Fusão Vertebral , Estenose Espinal , Humanos , Estenose Espinal/diagnóstico por imagem , Estenose Espinal/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Canal Medular/diagnóstico por imagem , Canal Medular/cirurgia
5.
Chemosphere ; 334: 139013, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37224972

RESUMO

Understanding high-velocity pollutant transport dependent on the large hydraulic gradient and/or heterogeneity of the aquifer and criteria for the onset of post-Darcy flow have attracted considerable attention in water resources and environmental engineering applications. In this study, a parameterized model is established based on the equivalent hydraulic gradient (EHG) which affected by spatial nonlocality of nonlinear head distribution due to the inhomogeneity at a wide range of scales. Two parameters relevant to the spatially non-local effect were selected to predict the development of post-Darcy flow. Over 510 sets of laboratory one-dimensional (1-D) steady hydraulic experimental data were used to validate the performance of this parameterized EHG model. The results show that (1) the spatial nonlocal effect of the whole upstream is related to the mean grain size of the medium, and the anomalous variation due to the small grain size implies the existence of the particle size threshold. (2) The parameterized EHG model can effectively capture the nonlinear trend that fails to be described by the traditional local form of nonlinear models, even if the specific discharge stabilizes at the later stages. (3) The Sub-Darcy flow distinguished by the parameterized EHG model can be equated to the post-Darcy flow, and then the criteria for the post-Darcy flow will be strictly distinguished under the premise of determining the hydraulic conductivity. The results of this study facilitate the identification and prediction of high-velocity non-Darcian flow in wastewater management and provide insight into mass transport by advection at the fine-scale.


Assuntos
Água Subterrânea , Águas Residuárias , Movimentos da Água , Recursos Hídricos , Condutividade Elétrica
6.
Environ Sci Pollut Res Int ; 30(21): 60303-60313, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37022552

RESUMO

The study aims to determine how price fluctuations in metallic resource supplies impact China's environmental performance. This research evaluates the impact of the price volatility of nickel, aluminum, gold, and aluminum on environmental performance in China from 2001 to 2019 to provide an answer to this topic. By examining the robustness of outcomes, the conventional DCC-GARCH approach clarifies the study findings and offers wide policy implications for the most recent topicality CS-ARDL. According to the study, the fluctuation in metal prices significantly influences the nation's GDP. The research's findings show that over the sample period, the price volatility of metallic resources was 23%, and this shift implied a 17.24% change in environmental performance. The findings of the study so ensure that every effort will be made to prevent environmental instability by supporting financial resource volatility recovery via governmental agencies, environmental ministries, and departments. The research has several policy implications, including the necessity for different government aid programs and financial agreements that guarantee environmental growth and resilience. The research's policy recommendations are intended to lessen the impact of structural events and increase environmental effectiveness. Research on financial resource recovery is dispersed and understudied despite the issue having a growing corpus of literature.


Assuntos
Alumínio , Recursos Naturais , China , Conservação dos Recursos Naturais
7.
Sci Total Environ ; 873: 162264, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36842596

RESUMO

As a high-performance liquid rocket fuel, unsymmetrical dimethylhydrazine (UDMH) will produce wastewater during transportation, storage and cleaning containers. The wastewater will have a bad impact on human health and ecological environment, and it must be properly handled. There are many reports about the technical feasibility of UDMH wastewater treatment. Less attention is paid to analyzing the impact on the environment during the treatment process. This paper quantifies the environmental impacts and economic benefits of four advanced oxidation processes for the treatment of UDMH wastewater based on life cycle assessment and life cycle costing methods. Taking the UDMH wastewater produced by an aerospace group of Tianjin, China as the research object, using Fenton method, UV-Fenton method, electro catalytic oxidation (EC) with ruthenium iridium titanium (Ti/TiO2-RuO2-IrO2) as electrode and electro catalytic oxidation with boron-doped diamond (BDD) as electrode as treatment methods, on the basis of the laboratory test, the industrialized device is adopted. The resource consumption, energy consumption, pollutant discharge and cost were compared when the TOC removal rate was the same, and a better method of treating unsymmetrical dimethyl hydrazine wastewater was discussed. The results show that the impact on most types of environments is as follows: UV-Fenton < Fenton < EC (BDD) < EC (Ti/TiO2-RuO2-IrO2), and the four advanced oxidation methods are all beneficial to reduce eutrophication. The life cycle cost of UV-Fenton is the lowest (US$1.53/m3). Combined with environmental and economic analysis, it can be seen that UV-Fenton is the best choice. Through sensitivity analysis, it can be seen that reducing chemical reagents and electricity consumption, and changing the way of generating electricity to renewable energy can significantly reduce the environmental and economic impact. The life cycle cost of EC(BDD) as the electrode is the highest (US$26.20/m3), but it can achieve a TOC removal rate of 97.75 %, so it is a better choice when only the removal rate is required regardless of cost.

8.
Environ Pollut ; 301: 119041, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35217134

RESUMO

European natural peatlands have undergone long-term anthropogenic drainage activities that have severely decreased their functions, such as carbon sequestration. Recent rewetting has been conducted to restore the ecosystem services of peatlands and mitigate the emissions of potent greenhouse gases such as nitrous oxide (N2O). However, the magnitudes and spatial patterns of annual N2O fluxes and their mitigation potentials across European peatlands remain unknown. Here, we synthesized 492 annual N2O flux data points from 77 in situ studies across European peatlands and found that the soil annual N2O fluxes varied extensively from -1.08 to 33.40 kg N2O-N ha-1 yr-1; these results were significantly and interactively (P < 0.05) affected by the peatland status, climatic regime and nutrient supply type. Drainage significantly (P < 0.05) stimulated soil N2O emissions from natural minerotrophic rather than ombrotrophic peatlands, regardless of the climatic regime. Similarly, rewetting significantly (P < 0.05) reduced soil N2O emissions from drained minerotrophic rather than ombrotrophic peatlands, demonstrating that the high N2O emissions were driven by a simultaneous decline in the water table depth and increase in the soil nitrogen (N) availability. Magnitudes of the increases or decreases in N2O emissions due to drainage or rewetting were also significantly influenced by the land-use and drainage history before rewetting and in the years following drainage/rewetting, respectively. The estimated annual mean N2O emission total was found to be 90.42 (95% confidence interval: 64.49-122.57) Gg N2O-N in 2020 from European peatlands. Scenario analysis showed that drained peatlands should be rewetted expeditiously; postponing rewetting would cause larger emissions from continued N2O emissions from drained peatlands. Fully rewetting the drained peatlands used for forestry and peat extraction and partially rewetting those used for agriculture and grassland comprise a strategy for mitigating drained peatland N2O emissions without compromising food security.


Assuntos
Gases de Efeito Estufa , Óxido Nitroso , Agricultura , Ecossistema , Gases de Efeito Estufa/análise , Óxido Nitroso/análise , Solo
9.
Sci Total Environ ; 800: 149650, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34426368

RESUMO

Antibiotic resistance genes (ARGs) are extensively detected in various environmental media, whose risk assessment in the drinking water systems has not been comprehensive. This study established a new risk assessment of ARGs in the drinking water systems, considering the chlorine-resistance ability, transferability, and ARGs harboring potential of pathogens. The risk of ARGs in a typical drinking water reservoir was also evaluated based on the detection of ARGs and antibiotic-resistant bacteria (ARB). Fourteen ARGs were detected with a relative concentration range of 10-4-10-3 (ARGs/16S rRNA gene). Five isolated ARB were identified as human opportunistic pathogens, one of which (Pseudomonas aeruginosa HLS-6, CCTCC AB 2017269) is resistant to hundreds of milligrams per liter levels of antibiotics and low-level chlorine. This result indicated that ARB tolerant to high-levels of antibiotics could be isolated from environments containing trace levels of antibiotics. Moreover, complete genome sequencing confirmed the inclusion of ARGs (sul1, aadA2) on the class I integron in HLS-6, indicating that the risk of ARGs in this drinking water reservoir could be classified as resistance risk ranking in drinking water system 1 (R3DW 1). The risk assessment of ARGs in this study provides a clear understanding of ARG risk in drinking water systems. The results reveal that the ARGs and ARB contamination of drinking water reservoirs pose significant challenges for drinking water treatment efficiency and affect drinking water safety.


Assuntos
Água Potável , Purificação da Água , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Antibacterianos/análise , Água Potável/análise , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Humanos , RNA Ribossômico 16S , Medição de Risco
10.
Environ Monit Assess ; 191(4): 210, 2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30850905

RESUMO

As an important causative factor of environmental accidents, natural disasters have recently received much attention for environmental risk assessment. Typhoons are one of the most frequent natural disasters in the northern Pacific Ocean and South China Sea and cause enormous damage to agriculture, daily livelihood, and industry. In this study, an environmental risk assessment for industrial enterprises is conducted when considering typhoon disasters. First, a Na-tech (natural hazard triggering technological disasters) environmental risk assessment index system with the aid of an analytic hierarchy process and fuzzy evaluation model (ERA-FAM) is developed to explore the major determinants related to risk level. The impact of typhoon disasters on environmental risk from chemical enterprises is discussed using a comparative analysis of risk levels with and without typhoon disaster scenarios. A chemical plant located in Zhejiang, China, is selected as a case study using this methodology. Three hypothetical scenarios are assumed, based on actual situations, to explore the impact of various factors on environmental risk. The results demonstrate that production factors and surrounding environmental conditions are the most sensitive factors for typhoon disasters, while emergency preparation is most important for reducing environmental risk. The influence of typhoons on environmental risk values is much higher for enterprises with imperfect management and vulnerable water risk receptors. Incorporating disaster management into environmental risk management will aid in developing strategies and policies for environmental risk mitigation and risk reduction practices.


Assuntos
Tempestades Ciclônicas/prevenção & controle , Desastres/prevenção & controle , Monitoramento Ambiental/métodos , Indústrias , Gestão da Segurança/métodos , China , Lógica Fuzzy , Humanos , Modelos Teóricos , Oceano Pacífico , Medição de Risco
11.
Exp Ther Med ; 17(3): 1802-1812, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30783452

RESUMO

The aim of the present study was to compare the in-hospital direct medical costs of patients with pelvic fracture treated with minimally invasive surgery (MIS) or open reduction and internal fixation (ORIF). A retrospective, single-center, cohort, and comparative study was performed. Administrative information and clinical results, in addition to cost data, were collected and analyzed. A cost minimization analysis method was used to evaluate the costs of two different surgical techniques. A total of 128 patients diagnosed with pelvic fracture were included in this study; 62 were treated with MIS and 66 underwent ORIF. No significant difference was observed between the 2 groups in terms of patients' clinical baseline characteristics. The operative time, length of incision, intra-operative blood loss, and post-operative length of stay in the MIS group were significantly different compared with those in the ORIF group. The cost-minimization analysis demonstrated that the cost effectiveness of MIS was better than ORIF as the MIS was associated with a significantly lower total in-hospital direct medical cost ($8,900 vs. $5,786, P=0.032), compared with ORIF. The cost-minimization analysis demonstrated that for similar clinical baseline characteristics as well as outcomes, there were differences in direct hospitalization cost of two surgical techniques, and MIS had a lower cost on average than ORIF.

12.
Artigo em Inglês | MEDLINE | ID: mdl-30764542

RESUMO

Considering the preference of green consumers for remanufactured products, a dual-sale-channel supply chain model with government non-intervention, government remanufacturing subsidy policy, and carbon tax policy is constructed, respectively. The difference of the optimal decision between the firm and the government under the two policies is discussed in this paper. Meanwhile, we analyze the influence of green consumers on the government's optimal decision, based on social welfare maximization. It is found that without government intervention, social welfare is the lowest. The carbon tax policy is better when the proportion of green consumers and the environmental coefficient are extreme or moderate at the same time. Otherwise, the subsidy policy is better. The carbon tax policy is more effective than the subsidy policy in controlling carbon emissions. Profit-sharing contracts should be established by enterprises and governments to achieve win⁻win results.


Assuntos
Pegada de Carbono/economia , Carbono/economia , Política Ambiental/economia , Financiamento Governamental , Indústria Manufatureira/economia , Reciclagem/economia , Impostos , China , Tomada de Decisões , Governo Federal , Humanos , Modelos Econômicos , Seguridade Social/economia
13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 1334-1337, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946139

RESUMO

The aim of this study was to explore a novel, low-cost smartphone-based biosensor system and establish an efficient analysis method for the detection of potential stress biomarker, salivary α-amylase(sAA). This system consists of Smartphone with sAA-detection, Screen-printed electrodes(SPEs) and potentiostat module. The presented technique that using a small perturbation to obtain a linearized response could affect the composition of the sample as to cyclic voltammetry which repeatedly reduces and oxidizes the sample. For application, 6 healthy graduate students took a 5 minutes Trier Social Stress Test(TSST). Results show that this method could detect sAA activities conveniently and accurately. Calibration curve of sAA whose quantitative range is from 50 and 1200 U mL-1 with a limit of detection(LOD) of 1.6 U mL-1, is Y=-52.324X+295.63, R^2=0.9933. After psychological stress, sAA secretion was significant verified. It is concluded that this smartphone-based sAA detection system is reliable for determination of Salivary α-amylase and useful in the assessment of Psychological stress.


Assuntos
Técnicas Biossensoriais , Smartphone , Humanos , Saliva , alfa-Amilases Salivares , Estresse Psicológico , Estudantes
14.
Huan Jing Ke Xue ; 39(7): 3102-3109, 2018 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-29962132

RESUMO

Penicillin is the most widely used and longest-lived antibiotic in the pharmaceutical industry. It belongs to the bio-fermentation chass of drugs, with a large amount of fermentation exhaust containing volatile organic compounds (VOCs) generated during the process of penicillin production, which have a serious impact on the environment. In this study, the pollution characteristics of the fermented exhaust are studied by using investigation and testing the souces of the pollution and via a health risk assessment model. The main results show that 23 kinds of VOCs were detected in the penicillin fermentation exhaust. The main pollutants included vinyl acetate trifluorotrichloroethane, dichlorotetrafluoroethane, and methylene chloride. In the heating stage, holding stage, cooling stage, and fermentation stage, the proportion of chlorinated hydrocarbons was the highest, followed by esters, and the total amount of these two kinds of substances accounted for more than 90% of total volatile organic compounds (TVOCs). Using the model of health risk assessment, the noncarcinogenic risk value of the total fermented exhaust was 4.98×10-5, which estimating the risk value by concentration gradient expansion is much lower than the maximum acceptable level (5×10-5 a-1) recommended by the International Commission on Radiation Protection (ICRP), which will not cause certain non-carcinogenic risk to the exposed population. VOCs in fermentation exhaust also have carcinogenic effects on human beings. The main health hazards to humans are 1,3-butadiene, dichloromethane, methyl chloride, carbon tetrachloride, benzene, and 1,1-dichloroethane.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Fermentação , Penicilinas , Compostos Orgânicos Voláteis/efeitos adversos , Indústria Farmacêutica , Monitoramento Ambiental , Humanos , Medição de Risco
16.
Sci Rep ; 7: 46073, 2017 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-28393879

RESUMO

Fragmentation and reduced continuity of habitat patches threaten the environment and biodiversity. Recently, ecological networks are increasingly attracting the attention of researchers as they provide fundamental frameworks for environmental protection. This study suggests a set of procedures to construct an ecological network. First, we proposed a method to construct a landscape resistance surface based on the assessment of habitat quality. Second, to analyze the effect of the resistance surface on corridor simulations, we used three methods to construct resistance surfaces: (1) the method proposed in this paper, (2) the entropy coefficient method, and (3) the expert scoring method. Then, we integrated habitat patches and resistance surfaces to identify potential corridors using graph theory. These procedures were tested in Changzhou, China. Comparing the outputs of using different resistance surfaces demonstrated that: (1) different landscape resistance surfaces contribute to how corridors are identified, but only slightly affect the assessment of the importance of habitat patches and potential corridors; (2) the resistance surface, which is constructed based on habitat quality, is more applicable to corridor simulations; and (3) the assessment of the importance of habitat patches is fundamental for ecological network optimization in the conservation of critical habitat patches and corridors.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , China , Simulação por Computador , Entropia
17.
Hum Vaccin Immunother ; 13(1): 111-116, 2017 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-27648636

RESUMO

Vaccination is the practiced and accessible measure for preventing influenza infection. Because chicken embryos used for vaccine production have various insufficiencies, more efficient methods are needed. African green monkey kidney (Vero) cells are recommended by the World Health Organization (WHO) as a safe substitute for influenza vaccine production for humans. However, the influenza virus usually had low-yield in Vero cells, which limits the usage of Vero cellular vaccines. This study used 2 high-yield influenza viruses in Vero cells: A/Yunnan/1/2005Va (H3N2) and B/Yunnan/2/2005Va (B) as donor viruses. It used 3 wild strain viruses to reassort new adaptation viruses, including: A/Tianjin/15/2009(H1N1), A/Fujian/196/2009(H3N2), and B/Chongqing/1384/2010(B). These three new viruses could maintain the characteristic of high-yield in Vero cells. Furthermore, they could keep the immunogenic characteristics of the original wild influenza viruses. Importantly, these viruses were shown as safe in chicken embryo and guinea pigs assessment systems. These results provide an alternative method to produce influenza vaccine based on Vero cells.


Assuntos
Técnicas de Cultura de Células , Vírus da Influenza A Subtipo H1N1/patogenicidade , Vírus da Influenza A Subtipo H3N2/patogenicidade , Vírus da Influenza B/patogenicidade , Vacinas contra Influenza/efeitos adversos , Vírus Reordenados/patogenicidade , Tecnologia Farmacêutica , Animais , Chlorocebus aethiops , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Furões , Cobaias , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/crescimento & desenvolvimento , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/crescimento & desenvolvimento , Vírus da Influenza A Subtipo H3N2/imunologia , Vírus da Influenza B/genética , Vírus da Influenza B/crescimento & desenvolvimento , Vírus da Influenza B/imunologia , Vacinas contra Influenza/administração & dosagem , Camundongos Endogâmicos BALB C , Vírus Reordenados/genética , Vírus Reordenados/crescimento & desenvolvimento , Vírus Reordenados/imunologia , Células Vero
18.
Diagn Microbiol Infect Dis ; 68(3): 251-8, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20851549

RESUMO

Imipenem/cilastatin and meropenem are carbapenem antibiotics that are infused intravenously (IV) over 30 to 45 min. We evaluated probability of target attainment and cumulative probability of target attainment of 30-min and 3-h infusions for imipenem/cilastatin and meropenem. Eighteen healthy adults in a randomized, 4-phase, crossover study received 1000 mg of imipenem/cilastatin or meropenem as a single-dose IV over 30 min or 3 h. A population pharmacokinetics analysis using a 2-compartment IV infusion model was performed. Monte Carlo simulations using various dosage regimens at steady-state and 30-min and 3-h infusion rates were performed to evaluate the probabilities of attaining 20% (bacteriostatic), 30%, and 40% (maximum kill) time above the MIC. Three-hour infusions of imipenem/cilastatin and meropenem improved the cumulative probability of target attainment for a variety of populations of microorganisms compared to 30-min infusions. Prolonged infusions have the potential to optimize efficacy of imipenem/cilastatin and meropenem.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Cilastatina/administração & dosagem , Cilastatina/farmacocinética , Imipenem/administração & dosagem , Imipenem/farmacocinética , Tienamicinas/administração & dosagem , Tienamicinas/farmacocinética , Adulto , Combinação Imipenem e Cilastatina , Estudos Cross-Over , Combinação de Medicamentos , Feminino , Humanos , Infusões Intravenosas/métodos , Masculino , Meropeném , Pessoa de Meia-Idade , Método de Monte Carlo , Fatores de Tempo
19.
Antimicrob Agents Chemother ; 51(11): 4085-9, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17846139

RESUMO

The objective of these analyses was to assess the penetration of tigecycline into colon wall tissue and epithelial lining fluid (ELF). The analyses included data from subjects without infection (phase 1) and patients with intra-abdominal infections (phase 2/3). Steady-state serum samples were collected from all subjects/patients (n = 577), while colon wall specimens (n = 23) and ELF specimens (n = 30) were obtained from subjects without infection. Tissue and serum data were simultaneously comodeled by using the BigNPAG program, and a four-compartment, open model with zero-order intravenous input and first-order elimination was employed. To examine the full range of tissue penetration and the associated probabilities of occurrence, a 9,999-subject Monte Carlo simulation was performed with two outputs, one for ELF penetration and one for colon wall tissue penetration. Data were well fit using models described above, with all r(2) values above 0.95. For subjects without infection, the median (5th and 95th percentiles) colon wall and ELF penetration ratios were 1.73 (0.160 and 199) and 1.15 (0.561 and 5.23), respectively. Simulation results predict that tissue penetration varies considerably and likely explain unexpected clinical outcomes for those patients infected with strains at margins of the MIC distribution.


Assuntos
Colo/metabolismo , Epitélio/metabolismo , Minociclina/análogos & derivados , Método de Monte Carlo , Adolescente , Adulto , Antibacterianos/sangue , Antibacterianos/farmacocinética , Área Sob a Curva , Colo/microbiologia , Simulação por Computador , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Minociclina/sangue , Minociclina/farmacocinética , Modelos Biológicos , Tigeciclina , Distribuição Tecidual
20.
Clin Pharmacol Ther ; 80(5): 531-8, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17112809

RESUMO

BACKGROUND: Studies examining sex differences in CYP3A activity have produced conflicting results. Our objective is to investigate whether sex differences exist in CYP3A activity as assessed by intravenous (IV) or oral midazolam pharmacokinetic analysis in healthy volunteers. METHODS: Data from 13 previous studies were used. A single dose of IV midazolam (0.025 mg/kg) was administered to 66 white adults (37 women and 29 men; mean age, 36.3+/-7.7 years). A single dose of oral midazolam, 0.075 mg/kg (5 studies), 0.15 mg/kg (1 study), or 5 mg (1 study), was administered to 72 adults (71 white and 1 Asian; 37 women and 35 men; mean age, 38.3+/-8.9 years). Pharmacokinetic parameters were determined via population methods by use of a nonparametric adaptive grid program and a 2-compartment IV and 1-compartment oral absorption model. The maximum a posteriori probability Bayesian method was used to estimate each subject's pharmacokinetic parameters. Monte Carlo simulation was performed to determine the probability distribution of the area under the concentration-time curves (AUCs). RESULTS: Women exhibited 11% higher mean weight-corrected total body midazolam clearance and 28% higher oral clearance compared with men (P

Assuntos
Citocromo P-450 CYP3A/metabolismo , Midazolam/farmacocinética , Administração Oral , Adulto , Ansiolíticos/administração & dosagem , Ansiolíticos/farmacocinética , Área Sob a Curva , Teorema de Bayes , Ensaios Clínicos como Assunto , Feminino , Humanos , Injeções Intravenosas , Masculino , Taxa de Depuração Metabólica , Midazolam/administração & dosagem , Método de Monte Carlo , Fatores Sexuais
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