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1.
J Am Chem Soc ; 146(5): 3075-3085, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38174850

RESUMO

Billions of populations are suffering from the supply-demand imbalance of clean water, resulting in a global sustainability crisis. Membrane desalination is a promising method to produce fresh water from saline waters. However, conventional membranes often encounter challenges related to low water permeation, negatively impacting energy efficiency and water productivity. Herein, we achieve ultrafast desalination over the newly developed alkadiyne-pyrene conjugated frameworks membrane supported on a porous copper hollow fiber. With membrane distillation, the membrane exhibits nearly complete NaCl rejection (>99.9%) and ultrahigh fluxes (∼500 L m-2 h-1) from the seawater salinity-level NaCl solutions, which surpass the commercial polymeric membranes with at least 1 order of magnitude higher permeability. Experimental and theoretical investigations suggest that the large aspect ratio of membrane pores and the high evaporation area contribute to the high flux, and the graphene-like hydrophobic surface of conjugated frameworks exhibits complete salt exclusion. The simulations also confirm that the intraplanar pores of frameworks are impermeable for water and ions.

2.
Front Public Health ; 10: 938913, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910925

RESUMO

Background: Mycobacterium tuberculosis infection remains a public health concern worldwide. The diagnosis and treatment of disseminated M. tuberculosis is very difficult, so we shared our experiences and lessons learned in this case report. Case Presentation: A 36-year-old female with a history of epilepsy presented to our hospital with fever, upper abdominal pain, muscle soreness in limbs for 7 days, and shortness of breath for 4 days. On admission, she presented with acute respiratory distress syndrome (ARDS) and liver dysfunction. Due to the critical nature of her clinical presentation, the patient was admitted directly to the Intensive Care Unit (ICU), received mechanical ventilation in prone position and VV-ECMO treatment. Her condition improved gradually, and the ECMO was removed after 7 days and she was weaned off the ventilator after 8 days. However, her fever recurred and she underwent PET-CT examination, liver contrast ultrasound, acid-fast staining and second-generation sequencing of cerebrospinal fluid, which confirmed M. tuberculosis infection. Conclusion: This case report briefly described the treatment and diagnosis of a critically ill patient with intra and extra-pulmonary tuberculosis infection. Timely and appropriate treatment is crucial to save lives, but the timing of ECMO treatment needs to be carefully considered for patients with ARDS caused by tuberculosis.


Assuntos
Oxigenação por Membrana Extracorpórea , Mycobacterium tuberculosis , Síndrome do Desconforto Respiratório , Adulto , Estado Terminal/terapia , Feminino , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/terapia
3.
Front Med (Lausanne) ; 9: 938536, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35966841

RESUMO

Background: Sepsis-induced cardiomyopathy significantly increased the mortality of patients with sepsis. The diagnostic criteria for septic cardiomyopathy has not been unified, which brings serious difficulties to clinical treatment. This study aimed to provide evidence for the early identification and intervention in patients with sepsis by clarifying the relationship between the ultrasound phenotype of septic cardiomyopathy and the prognosis of patients with sepsis. Methods: This was a multicenter, prospective cohort study. The study population will consist of all eligible consecutive patients with sepsis or septic shock who meet the Sepsis 3.0 diagnostic criteria and were aged ≥18 years. Clinical data and echocardiographic measurements will be recorded within 2 h, at the 24th hour, at the 72nd hour, and on the 7th day after admission. The prevalence of each phenotype will be described as well, and their association with prognosis will be analyzed statistically. Discussion: To achieve early recognition, prevent reinjury, achieve precise treatment, and reduce mortality in patients with sepsis, it is important to identify septic cardiac alterations and classify the phenotypes at all stages of sepsis. First, there is a lack of studies on the prevalence of each phenotype in Chinese populations. Second, each phenotype and its corresponding prognosis are not clear. In addition, the prognosis of patients with normal cardiac ultrasound phenotypes vs. those with suppressed or hyperdynamic cardiac phenotypes is unclear. Finally, this study was designed to collect data at four specific timing, then the timing of occurrence, duration, changes over time, impact to outcomes of each phenotype will probably be found. This study is expected to establish a standard and objective method to assess the ultrasound phenotype of septic cardiomyopathy due to its advantages of visualization, non-invasiveness and reproducibility, and to provide more precise information for the hemodynamic management of septic patients. In addition, this research will promote the clinical application of critical care ultrasound, which will play an important role in medical education and make ultrasound the best method to assess cardiac changes in sepsis. Trial registration: https://clinicaltrials.gov/ct2/show/NCT05161104, identifier NCT05161104.

4.
J Intensive Med ; 1(2): 117-122, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36943821

RESUMO

Background: The outbreak of coronavirus disease 2019 (COVID-19) has posed a huge threat to human health. However, little is known regarding the risk factors associated with COVID-19 severity. We aimed to explore early-stage disease risk factors associated with eventual disease severity. Methods: This study enrolled 486 hospitalized, non-intensive care unit (ICU)-admitted adult patients with COVID-19 (age ≥ 18 years) treated at Wuhan Jinyintan Hospital, who were divided into three groups according to disease severity. The demographic, clinical, and laboratory data at admission and clinical outcomes were compared among severity groups, and the risk factors for disease severity were identified by multiple regression analysis. Results: Of 486 patients with COVID-19, 405 (83.33%) were discharged, 33 (6.71%) died outside of the ICU, and 48 (7.20%) were still being treated in the ICU by the time the study period ended. Significant differences in age, lymphocyte counts, and the levels of procalcitonin, aspartate aminotransferase, and D-dimer (P < 0.001 for all) among the three groups. Further analysis showed that older age, decreased lymphocyte counts, and increased procalcitonin, aspartate aminotransferase, and D-dimer levels were significantly associated with disease progression. Conclusion: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may impair the immune system, the blood coagulation system, and hepatic and cardiac function. Some clinical characteristics and laboratory findings can help identify patients with a high risk of disease severity, which can be significant for appropriate resource allocation during the COVID-19 pandemic.

5.
Biomed Rep ; 4(2): 131-134, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26893826

RESUMO

Colon cancer is one of the most common, lethal diseases worldwide. Tumor metastasis and chemotherapy resistance are the main reasons for its poor prognosis and high fatality rate. Tumor development is thought of as one of the most complex cellular events as it is a multi-step cascading process involving infinite proliferation, invasion and immigration. Recently, increasing studies have demonstrated that microRNA-126 (miR-126) has an important role in colon cancer. The expression of miR-126 decreased significantly in colon cancer, particularly in highly metastatic cell lines. miR-126 controls tumor cell growth, metastasis and survival via inactivation of the oncogene signaling pathway, indicating that miR-126 may serve as a therapeutic target for anticancer therapy. Potentially, miR-126 was also reported to be an ideal molecular target as a novel biomarker for liver metastasis from colorectal cancer due to its changeable expression level. In the present review, the current knowledge regarding regulatory function of miR-126 is summarized along with its underlying mechanisms in colon cancer.

6.
PLoS One ; 9(9): e107874, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25232872

RESUMO

Plant senescence is a critical life history process accompanied by chlorophyll degradation and has large implications for nutrient resorption and carbohydrate storage. Although photoperiod governs much of seasonal leaf senescence in many plant species, temperature has also been shown to modulate this process. Therefore, we hypothesized that climate warming would significantly impact the length of the plant growing season and ultimate productivity. To test this assumption, we measured the effects of simulated autumn climate warming paradigms on four native herbaceous species that represent distinct life forms of alpine meadow plants on the Tibetan Plateau. Conditions were simulated in open-top chambers (OTCs) and the effects on the degradation of chlorophyll, nitrogen (N) concentration in leaves and culms, total non-structural carbohydrate (TNC) in roots, growth and phenology were assessed during one year following treatment. The results showed that climate warming in autumn changed the senescence process only for perennials by slowing chlorophyll degradation at the beginning of senescence and accelerating it in the following phases. Warming also increased root TNC storage as a result of higher N concentrations retained in leaves; however, this effect was species dependent and did not alter the growing and flowering phenology in the following seasons. Our results indicated that autumn warming increases carbohydrate accumulation, not only by enhancing activities of photosynthetic enzymes (a mechanism proposed in previous studies), but also by affecting chlorophyll degradation and preferential allocation of resources to different plant compartments. The different responses to warming can be explained by inherently different growth and phenology patterns observed among the studied species. The results implied that warming leads to changes in the competitive balance among life forms, an effect that can subsequently shift vegetation distribution and species composition in communities.


Assuntos
Clorofila/metabolismo , Delphinium/metabolismo , Elymus/metabolismo , Metabolismo dos Carboidratos , Delphinium/crescimento & desenvolvimento , Elymus/crescimento & desenvolvimento , Aquecimento Global , Dormência de Plantas , Folhas de Planta/metabolismo , Estações do Ano , Tibet
7.
Artigo em Inglês | MEDLINE | ID: mdl-25161698

RESUMO

BACKGROUND: Dendritic cells (DCs) are important mediators of innate and adaptive immune responses, but the gene networks governing their lineage differentiation and maturation are poorly understood. To gain insight into the mechanisms that promote human DC differentiation and contribute to the acquisition of their functional phenotypes, we performed genome-wide base-resolution mapping of 5-methylcytosine in purified monocytes and in monocyte-derived immature and mature DCs. RESULTS: DC development and maturation were associated with a great loss of DNA methylation across many regions, most of which occurs at predicted enhancers and binding sites for known transcription factors affiliated with DC lineage specification and response to immune stimuli. In addition, we discovered novel genes that may contribute to DC differentiation and maturation. Interestingly, many genes close to demethylated CG sites were upregulated in expression. We observed dynamic changes in the expression of TET2, DNMT1, DNMT3A and DNMT3B coupled with temporal locus-specific demethylation, providing possible mechanisms accounting for the dramatic loss in DNA methylation. CONCLUSIONS: Our study is the first to map DNA methylation changes during human DC differentiation and maturation in purified cell populations and will greatly enhance the understanding of DC development and maturation and aid in the development of more efficacious DC-based therapeutic strategies.

8.
Environ Geochem Health ; 36(3): 333-43, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23828236

RESUMO

Soils in the vicinity of roads are recipients of contaminants from traffic emissions. In order to obtain a better understanding of the impacts of traffic on soils, a total of 225 surface soil samples were collected from an urban park (Phoenix Park, Dublin, Ireland) in a grid system. Metal (Pb, Cu and Zn) concentrations were determined using a portable X-ray fluorescence analyzer. Strong spatial variations for the concentrations of Pb, Cu and Zn were observed. The spatial distribution maps created using geographical information system techniques revealed elevated metal concentrations close to the main traffic route in the park. The relationships between the accumulation of Pb, Cu and Zn in the roadside soils and the distance from the road were well fitted with an exponential model. Elevated metal concentrations from traffic pollution extended to a distance of approximately 40 m from the roadside. The results of this study provide useful information for the management of urban parks particularly in relation to policies aimed at reducing the impact of traffic related pollution on soils.


Assuntos
Cobre/análise , Chumbo/análise , Recreação , Poluentes do Solo/análise , Saúde da População Urbana , Emissões de Veículos , Zinco/análise , Irlanda , Controle de Qualidade
9.
J Chem Phys ; 134(11): 114105, 2011 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-21428605

RESUMO

Sensitivity analysis is a valuable task for assessing the effects of biological variability on cellular behavior. Available techniques require knowledge of nominal parameter values, which cannot be determined accurately due to experimental uncertainty typical to problems of systems biology. As a consequence, the practical use of existing sensitivity analysis techniques may be seriously hampered by the effects of unpredictable experimental variability. To address this problem, we propose here a probabilistic approach to sensitivity analysis of biochemical reaction systems that explicitly models experimental variability and effectively reduces the impact of this type of uncertainty on the results. The proposed approach employs a recently introduced variance-based method to sensitivity analysis of biochemical reaction systems [Zhang et al., J. Chem. Phys. 134, 094101 (2009)] and leads to a technique that can be effectively used to accommodate appreciable levels of experimental variability. We discuss three numerical techniques for evaluating the sensitivity indices associated with the new method, which include Monte Carlo estimation, derivative approximation, and dimensionality reduction based on orthonormal Hermite approximation. By employing a computational model of the epidermal growth factor receptor signaling pathway, we demonstrate that the proposed technique can greatly reduce the effect of experimental variability on variance-based sensitivity analysis results. We expect that, in cases of appreciable experimental variability, the new method can lead to substantial improvements over existing sensitivity analysis techniques.


Assuntos
Bioquímica/métodos , Biologia Computacional/métodos , Modelos Biológicos , Algoritmos , Análise de Variância , Receptores ErbB/genética , Receptores ErbB/metabolismo , Transdução de Sinais
10.
BMC Bioinformatics ; 11: 246, 2010 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-20462443

RESUMO

BACKGROUND: Sensitivity analysis is an indispensable tool for the analysis of complex systems. In a recent paper, we have introduced a thermodynamically consistent variance-based sensitivity analysis approach for studying the robustness and fragility properties of biochemical reaction systems under uncertainty in the standard chemical potentials of the activated complexes of the reactions and the standard chemical potentials of the molecular species. In that approach, key sensitivity indices were estimated by Monte Carlo sampling, which is computationally very demanding and impractical for large biochemical reaction systems. Computationally efficient algorithms are needed to make variance-based sensitivity analysis applicable to realistic cellular networks, modeled by biochemical reaction systems that consist of a large number of reactions and molecular species. RESULTS: We present four techniques, derivative approximation (DA), polynomial approximation (PA), Gauss-Hermite integration (GHI), and orthonormal Hermite approximation (OHA), for analytically approximating the variance-based sensitivity indices associated with a biochemical reaction system. By using a well-known model of the mitogen-activated protein kinase signaling cascade as a case study, we numerically compare the approximation quality of these techniques against traditional Monte Carlo sampling. Our results indicate that, although DA is computationally the most attractive technique, special care should be exercised when using it for sensitivity analysis, since it may only be accurate at low levels of uncertainty. On the other hand, PA, GHI, and OHA are computationally more demanding than DA but can work well at high levels of uncertainty. GHI results in a slightly better accuracy than PA, but it is more difficult to implement. OHA produces the most accurate approximation results and can be implemented in a straightforward manner. It turns out that the computational cost of the four approximation techniques considered in this paper is orders of magnitude smaller than traditional Monte Carlo estimation. Software, coded in MATLAB, which implements all sensitivity analysis techniques discussed in this paper, is available free of charge. CONCLUSIONS: Estimating variance-based sensitivity indices of a large biochemical reaction system is a computationally challenging task that can only be addressed via approximations. Among the methods presented in this paper, a technique based on orthonormal Hermite polynomials seems to be an acceptable candidate for the job, producing very good approximation results for a wide range of uncertainty levels in a fraction of the time required by traditional Monte Carlo sampling.


Assuntos
Análise de Variância , Método de Monte Carlo , Transdução de Sinais , Algoritmos , Fenômenos Bioquímicos
11.
J Chem Phys ; 131(9): 094101, 2009 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-19739843

RESUMO

Sensitivity analysis is an indispensable tool for studying the robustness and fragility properties of biochemical reaction systems as well as for designing optimal approaches for selective perturbation and intervention. Deterministic sensitivity analysis techniques, using derivatives of the system response, have been extensively used in the literature. However, these techniques suffer from several drawbacks, which must be carefully considered before using them in problems of systems biology. We develop here a probabilistic approach to sensitivity analysis of biochemical reaction systems. The proposed technique employs a biophysically derived model for parameter fluctuations and, by using a recently suggested variance-based approach to sensitivity analysis [Saltelli et al., Chem. Rev. (Washington, D.C.) 105, 2811 (2005)], it leads to a powerful sensitivity analysis methodology for biochemical reaction systems. The approach presented in this paper addresses many problems associated with derivative-based sensitivity analysis techniques. Most importantly, it produces thermodynamically consistent sensitivity analysis results, can easily accommodate appreciable parameter variations, and allows for systematic investigation of high-order interaction effects. By employing a computational model of the mitogen-activated protein kinase signaling cascade, we demonstrate that our approach is well suited for sensitivity analysis of biochemical reaction systems and can produce a wealth of information about the sensitivity properties of such systems. The price to be paid, however, is a substantial increase in computational complexity over derivative-based techniques, which must be effectively addressed in order to make the proposed approach to sensitivity analysis more practical.


Assuntos
Análise de Variância , Estudos de Casos e Controles , Biologia Computacional , Simulação por Computador , Modelos Biológicos , Sensibilidade e Especificidade , Técnicas de Laboratório Clínico , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Método de Monte Carlo , Pesquisa , Transdução de Sinais , Software , Biologia de Sistemas , Washington
12.
Coron Artery Dis ; 19(3): 173-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18418234

RESUMO

BACKGROUND: Marked variability exists in coronary artery collaterals in patients with ischemic heart disease. Multiple factors are thought to play a role in collateral development; however, the contribution of hypoxia inducible factor-1alpha (HIF-1alpha), which is a transcriptional activator that functions as a master regulator of oxygen homeostasis, is not completely clear. It could play an important role in modulating collateral development. OBJECTIVE: The objective of this study is to investigate the changes and significance of expression of HIF-1alpha in patients with coronary artery collaterals. METHODS: Collateral vessels were determined in 98 patients with >or=70% narrowing of at least one coronary artery without earlier revascularization, 42 patients with coronary artery collaterals and 56 patients with no coronary artery collaterals. Extent of collaterals was expressed as scores according to the Rentrop scoring system. Another 50 cases with normal coronary arteries were selected as control. The levels of HIF-1alpha protein expression in monocyte and lymphocyte in the participants were tested by immunohistochemistry (IHC) and western blot; mRNA levels were measured using reverse transcriptase PCR technique. RESULTS: Compared with the control with normal coronary artery, the patients had higher expression of HIF-1alpha protein tested by IHC and western blot (52.6+/-10.2 vs. 13.7+/-6.2 by IHC, 50.8+/-4.5 vs. 6.5+/-1.8 by western blot); furthermore, significantly higher HIF-1alpha expression was observed in patients with collaterals compared with patients with no collaterals (81.5+/-11.8 vs. 20.7+/-9.4 by IHC; 87.2+/-6.5 vs. 9.5+/-1.4 by western blot). On the transcriptional levels of HIF-1alpha, the result was the same as the protein, there was significant difference of HIF-1alpha between the three groups. The patients with collaterals were the highest (127.3+/-23.9), followed by patients with no collaterals (35.7+/-12.3), and the control were the lowest (23.5+/-9.3). A highly positive correlation was observed between the expression/transcription of HIF-1alpha and collateral score (P<0.01, IHC: r1=0.78, reverse transcriptase PCR: r2=0.69, western blot: r3=0.84). CONCLUSION: These data suggest that higher inductions of HIF-1alpha are associated with coronary collaterals, thus implying that HIF-1alpha may promote coronary collateral formation. Detection of HIF-1alpha expression might be helpful to predict prognosis of patients with coronary artery disease.


Assuntos
Circulação Colateral , Doença da Artéria Coronariana/sangue , Subunidade alfa do Fator 1 Induzível por Hipóxia/sangue , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise
13.
Ying Yong Sheng Tai Xue Bao ; 19(12): 2593-8, 2008 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-19288709

RESUMO

This paper studied the phenotypic plasticity of Agriophyllum squarrosum under effects of soil nutrient and moisture contents and population density. The results showed that with the increase of soil nutrient content, the root/shoot ratio of A. squarrosum was decreased from 0.135 to 0.073. However, soil moisture content and population density had less effect on the root/shoot ratio. The plasticity of reproductive allocation of A. squarrosum as responding to the changes of soil nutrient and moisture contents was a "real plasticity", and the allocation was negatively correlated with soil nutrient content but positively correlated with soil moisture content. When soil nutrient content was high or moisture content was low, the reproductive allocation of A. squarrosum changed larger with plant size. Population density had no effects on the reproductive allocation, while plant size conditioned the allocation. Among the three test affecting factors, soil nutrient content had the greatest effects on the morphological characters and biomass of A. squarrosum.


Assuntos
Adaptação Biológica , Desenvolvimento Vegetal , Plantas/genética , Solo/análise , Água/análise , Alimentos , Fenótipo , Densidade Demográfica
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