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1.
Molecules ; 26(15)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34361601

RESUMO

The development of photothermal materials with a high light-to-heat conversion capability is essential for the utilization of clean solar energy. In this work, we demonstrate the use of a novel and sustainable concept involving cellulose liquefaction, rapid gelation, in situ synthesis and hot-press drying to convert cellulose and metal-organic framework (Prussian blue) into a stable photothermal bioplastic that can harvest sunlight and convert it into mechanical motion. As expected, the obtained Prussian blue@cellulose bioplastic (PCBP) can effectively absorb sunlight and the surface can be heated up to 70.3 °C under one sun irradiation (100 mW cm-2). As a demonstration of the practicality of PCBP, it was successfully used to drive a Stirling engine motion. Meanwhile, hot-pressing promotes the densification of the structure of PCBP and, therefore, improves the resistance to the penetration of water/non-aqueous liquids. Moreover, PCBP shows good mechanical properties and thermal stability. Given the excellent photothermal performance and environmentally friendly features of photothermal conversion bioplastic, we envisage this sustainable plastic film could play important roles toward diversified applications: a photothermal layer for thermoelectric generator, agricultural films for soil mulching and photothermal antibacterial activity, among others.

2.
Sensors (Basel) ; 20(11)2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32471159

RESUMO

Recently, the triangle algorithm has become the most widely used star identification algorithm because of its simplicity and convenience, where the magnitude information plays a key role in the construction of star map features. However, in practice, the magnitude information of the observed star map is often difficult to use, because they might contain errors or be lost in some worst cases. To solve this problem, we proposed a multi-view double-triangle algorithm for star identification in this paper. This algorithm constructs double-triangle features of stars with the angle and distance information of star points. Moreover, to reduce the influence of noise interference on the identification accuracy of the model, we built multi-view double-triangle features for the observed star map to improve the robustness of the algorithm. Synthetic and real experiments show that our algorithm has a high identification accuracy of more than 98.4% in face of "false star" noises and "missing star" noises, and our algorithm is not affected by the focal length and the shooting angle of the star sensor. Moreover, the results also show that our algorithm has good robustness, short identification time and reduced storage costs, which could be beneficial in practice.

3.
Chaos ; 28(2): 023101, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29495671

RESUMO

In this paper, a Cournot-Bertrand duopoly model with market share preference is established. Assume that there is a degree of product difference between the two firms, where one firm takes the price as a decision variable and the other takes the quantity. Both firms are bounded rational, with linear cost functions and demand functions. The stability of the equilibrium points is analyzed, and the effects of some parameters (α, ß, d and v1) on the model stability are studied. Basins of attraction are investigated and the evolution process is shown with the increase in the output adjustment speed. The simulation results show that instability will lead to the increase in the average utility of the firm that determines the quantity and reduce the average utility of the firm that determines price.

4.
Sensors (Basel) ; 15(9): 21033-53, 2015 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-26343655

RESUMO

A combination of genetic algorithm and particle swarm optimization (PSO) for vehicle routing problems with time windows (VRPTW) is proposed in this paper. The improvements of the proposed algorithm include: using the particle real number encoding method to decode the route to alleviate the computation burden, applying a linear decreasing function based on the number of the iterations to provide balance between global and local exploration abilities, and integrating with the crossover operator of genetic algorithm to avoid the premature convergence and the local minimum. The experimental results show that the proposed algorithm is not only more efficient and competitive with other published results but can also obtain more optimal solutions for solving the VRPTW issue. One new well-known solution for this benchmark problem is also outlined in the following.

5.
Int J Biol Macromol ; 268(Pt 2): 131790, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38677693

RESUMO

The demand for paper-based packaging materials as an alternative to incumbent disposable petroleum-derived polymers for food packaging applications is ever-growing. However, typical paper-based formats are not suitable for use in unconventional applications due to inherent limitations (e.g., excessive hydrophilicity, lack antimicrobial ability), and accordingly, enabling new capabilities is necessity. Herein, a simple and environmentally friendly strategy was proposed to introduce antimicrobial and hydrophobic functions to cellulose paper through successive chemical grafting of 3-aminopropyltriethoxysilane (APS) and cinnamaldehyde (CA). The results revealed that cellulose paper not only showed long-term antibacterial effect on different bacteria, but also inhibited a wide range of fungi. Encouragingly, the modified paper, which is fluorine-free, displays a high contact angle of 119.7°. Thus, even in the wet state, the modified paper can still maintain good mechanical strength. Meanwhile, the multifunctional composite papers have excellent biocompatibility and biodegradability. Compared with ordinary cellulose paper, multifunctional composite paper can effectively prolong the shelf life of strawberries. Therefore, the multifunctional composite paper represents good application potential as a fruit packaging material.


Assuntos
Acroleína , Celulose , Embalagem de Alimentos , Fragaria , Interações Hidrofóbicas e Hidrofílicas , Papel , Celulose/química , Celulose/análogos & derivados , Acroleína/análogos & derivados , Acroleína/química , Acroleína/farmacologia , Fragaria/microbiologia , Embalagem de Alimentos/métodos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Silanos/química , Conservação de Alimentos/métodos , Propilaminas/química , Testes de Sensibilidade Microbiana
6.
Plant Phenomics ; 6: 0198, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38939747

RESUMO

The pod and seed counts are important yield-related traits in soybean. High-precision soybean breeders face the major challenge of accurately phenotyping the number of pods and seeds in a high-throughput manner. Recent advances in artificial intelligence, especially deep learning (DL) models, have provided new avenues for high-throughput phenotyping of crop traits with increased precision. However, the available DL models are less effective for phenotyping pods that are densely packed and overlap in in situ soybean plants; thus, accurate phenotyping of the number of pods and seeds in soybean plant is an important challenge. To address this challenge, the present study proposed a bottom-up model, DEKR-SPrior (disentangled keypoint regression with structural prior), for in situ soybean pod phenotyping, which considers soybean pods and seeds analogous to human people and joints, respectively. In particular, we designed a novel structural prior (SPrior) module that utilizes cosine similarity to improve feature discrimination, which is important for differentiating closely located seeds from highly similar seeds. To further enhance the accuracy of pod location, we cropped full-sized images into smaller and high-resolution subimages for analysis. The results on our image datasets revealed that DEKR-SPrior outperformed multiple bottom-up models, viz., Lightweight-OpenPose, OpenPose, HigherHRNet, and DEKR, reducing the mean absolute error from 25.81 (in the original DEKR) to 21.11 (in the DEKR-SPrior) in pod phenotyping. This paper demonstrated the great potential of DEKR-SPrior for plant phenotyping, and we hope that DEKR-SPrior will help future plant phenotyping.

7.
Nanomaterials (Basel) ; 12(11)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35683745

RESUMO

While tremendous efforts have been dedicated to developing cellulose-based ultraviolet (UV)-blocking films, challenges still remain in simultaneously achieving high transparency, low haze and excellent UV shielding properties via simple and green strategy. Here, we present a facile and eco-friendly route to fabricate flexible, biodegradable and clear UV-shielding nano-MIL-88A(Fe)@carboxymethylated cellulose films (M(Fe)CCFs) via in situ synthesis of nano-MIL-88A(Fe) in carboxymethylated cellulose hydrogel followed by natural drying. The carboxymethylated cellulose film has high transmittance (93.2%) and low haze (1.8%). The introduction of nano-MIL-88A(Fe) endowed M(Fe)CCFs superior UV-shielding ability, while retaining high transmittance (81.5-85.3%) and low haze (2.5-4.9%). Moreover, M(Fe)CCFs showed stable UV blocking performance under UV irradiation, high temperature, acidic or alkaline conditions. Quite encouragingly, the UV-shielding ability of M(Fe)CCFs did not deteriorate, even after 30 days of immersion in aqueous solution, providing films with a long-term use capacity. Thus, M(Fe)CCFs show high potential in the UV protection field. Overall, these UV-blocking films with outstanding performances are a promising candidate to replace conventional film materials made from synthetic polymers in fields such as packaging and flexible electronics.

8.
Carbohydr Polym ; 273: 118535, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560947

RESUMO

It is still a challenge to realize super clear cellulose-based film materials with different functional combinations. This study presents a novel concept of fabricating flame-retardant, mechanically strong, UV and blue light double-blocking carboxymethylated cellulose-based nanocomposite bioplastics enabled by nano-metal organic framework (MIL-125(Ti)-NH2). Carboxymethylated cellulose gel with porous structure acts as nanoreactor and carboxyl groups as reactive sites to facilitate the growth and anchorage of nano-MIL-125(Ti)-NH2. Super clear bioplastics were obtained through hot-pressing. The results show that the neat carboxymethylated cellulose bioplastic possesses high transmittance (94.1% at 600 nm) and low haze (2.0% at 600 nm). The incorporation of nano-MIL-125(Ti)-NH2 enabled nanocomposite bioplastics to obtain UV and blue light double-shielding capability meanwhile retaining high transmittance (79-92.8%) and low haze (2.6-7.2%). Moreover, the incorporation of nano-MIL-125(Ti)-NH2 was found to significantly improve the mechanical strength and decrease the flammability of nanocomposite bioplastics. This facile strategy would direct nanocomposite bioplastics toward diversified applications.

9.
Polymers (Basel) ; 13(15)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34372036

RESUMO

From the perspective of sustainable development and practical applications, there has been a great need for the design of multifunctional transparent cellulose-based composite films. We herein propose a novel concept of improving the mechanical, fire-resistant and ultraviolet (UV)-blue light shielding properties of cellulose-based composite bioplastic films though in situ embedding nano-metal organic framework (MIL-125(Ti)-NH2) into regenerated cellulose gel. Regenerated cellulose hydrogel (CH) with a porous structure acts as a nanoreactor and stabilizer to facilitate the growth and anchorage of MIL-125(Ti)-NH2 nanoparticles (MNPs). Subsequently, hot-pressing induces the formation of transparent MIL-125(Ti)-NH2@cellulose bioplastics (MNP@CBPs). As expected, the MNP@CBPs exhibit exceptional UV-blue light shielding capability, while retaining satisfactory optical transmittance. Meanwhile, with the incorporation of MNPs, the mechanical strength of MNP@CBPs is increased by 6.5~25.9%. In addition, MNPs enhance the flame retardant effect of the MNP@CBPs. The limited oxygen index (LOI) of the MNP@CBPs increased from 21.95 to 27.01%. The hot-pressing process improves the resistance of the MNP@CBPs to the penetration of water/non-aqueous liquids. This simple strategy would direct sustainable multifunctional MNP@CBPs toward diversified applications: food containers or packaging materials that can reduce or eliminate food spoilage, screen protectors for blocking harmful light, and promising candidates for protective plastic products, among others.

10.
Polymers (Basel) ; 13(19)2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34641114

RESUMO

New kinds of inorganic-organic hybrid porous materials, metal-organic frameworks (MOFs), have shown great application potential in various fields, but their powdery nature limits their application to a certain extent. As a green and renewable biomass material in nature, cellulose fiber (CelF) has the advantages of biodegradability, recyclability and easy processing, and can be used as an excellent flexible substrate for MOFs. However, the efficient deposition of MOFs on CelF is still a great challenge for the development of this new material. Herein, polyaniline (PANI) and de-doped PANI (DPANI) with rich functional groups as a mediating layer was proposed to promote the in-situ growth and immobilization of some MOFs on CelF. The PANI (especially DPANI) layer greatly promoted the deposition of the four MOFs, and more encouragingly, significantly promoted the in-situ growth and nanocrystallization of MIL-100(Fe). MIL-100(Fe)@DPANI@CelF was selected as an adsorbent-photocatalyst to be used for the adsorptive-photocatalytic removal of ciprofloxacin (CIP) in water. The removal efficiency of CIP by MIL-100(Fe)@DPANI@CelF reached 82.78%, and the removal capacity of CIP was as high as 105.96 mg g-1. The study found that DPANI had a synergistic effect on both the in-situ growth of MIL-100(Fe) on CelF and the adsorption-photocatalysis of CIP in water. The universal platform of PANI-mediated in-situ growth and immobilization of MOFs on CelF constructed in this study widens the road for the development of MOF@CelF composites.

11.
Carbohydr Polym ; 229: 115455, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31826476

RESUMO

With the development of flexible electronic devices, flexible energy storage systems have been research hotpot. Conductive polymers is potential pseudocapacitor materials in energy storage field. Meanwhile, cellulose fiber with natural, degradable, renewable and flexible properties is one of tremendous promising alternatives to the flexible substrates. Hence, a polypyrrole@cobalt oxyhydroxide/cellulose fiber composite electrode is prepared via "liquid phase reduction" strategy in open system at room temperature. The composite electrode exhibits excellent electrochemical properties, which has a high specific capacitance and capacitance retention. The highest specific capacitance of 571.3 F g-1 at 0.2 A g-1 is obtained. Besides, the specific capacitance of the composite electrode has no significant loss, showing high cycle stability (93.02% after 1000 cycles). The excellent electrochemical properties can be ascribed to the introduction of cobalt oxyhydroxide, which restrains the volumetric change of polypyrrole in the electrochemical redox process, and promotes the rapid migration of electrons.

12.
Carbohydr Polym ; 207: 68-78, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30600053

RESUMO

We report a facile and effective method to fabricate clickable alkyne-functionalized cellulose fibers (ACFs) through in situ chemical oxidation copolymerization of 3-ethynylaniline and aniline under acidic aqueous solution. The effects of process variables on copolymer deposition onto CFs were investigated and suitable preparation conditions were identified. It was found that aniline significantly facilitated the polymerization of 3-ethynylaniline and shortened the preparation time of ACFs from 48 to 6 h. Antibacterial-modified cellulose fibers were prepared by binding ß-cyclodextrin (ß-CD) to cellulose fibers via click chemistry, followed by the inclusion of ciprofloxacin hydrochloride (CipHCl). The loading and releasing behaviors of CipHCl into/from click product (ACFs@Azide-ß-CD) were also revealed. The load amount of CipHCl into ACFs@Azide-ß-CD increased remarkably, and the release of CipHCl from ACFs@Azide-ß-CD was prolonged. The ACFs@Azide-ß-CD loaded with CipHCl exhibited higher and longer-term antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureu) compared with CFs and ACFs.

13.
Cell Mol Immunol ; 16(6): 602-610, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30327490

RESUMO

Granulocyte colony-stimulating factor (GM-CSF), produced by CD4+ T cells, has recently been implicated in the pathogenesis of inflammatory diseases, such as multiple sclerosis and juvenile arthritis. However, the role of GM-CSF-producing CD4+ T cells in sepsis remains unknown. This study reports peripheral changes in GM-CSF-producing CD4+ T cells in septic patients and the possible underlying mechanism by which GM-CSF influences the outcome of sepsis. Forty-three septic patients, 20 SIRS patients, and 20 healthy controls were enrolled in this study and followed for 28 days to assess mortality. We measured the peripheral frequency of GM-CSF+CD4+ T cells and recorded their associated relationship with disease progression. Our data demonstrated that peripheral GM-CSF-producing CD4+ T cells were significantly higher in septic patients than in both SIRS patients and healthy controls. These cells exhibit a memory phenotype and impaired IFN-γ-secreting capacity in sepsis patients. Using a receiver operating curve analysis with 8.01% as a cut-off point, the percentage of GM-CSF+CD4+ T cells could predict the outcome of septic patients. Combined with the increase in GM-CSF-producing CD4+ T cells, inflammatory cytokines IL-1ß and IL-6 were also upregulated. Using an in vitro neutrophil model, we found that GM-CSF inhibited C3aR expression, while inducing IL-8 production. Furthermore, this effect was transferrable in plasma from sepsis patients and was attenuated by inhibition of GM-CSF using an anti-GM-CSF antibody. These results indicate that GM-CSF-producing CD4+ T cells may serve as a marker of sepsis severity. Thus, targeting GM-CSF overproduction may benefit sepsis patients.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Pulmão/patologia , Sepse/diagnóstico , Adulto , Estudos de Coortes , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Sepse/imunologia , Sepse/mortalidade , Análise de Sobrevida
14.
Carbohydr Polym ; 198: 41-50, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30093017

RESUMO

A mild and effective strategy to prepare alkynyl-functionalized cellulose fibers (A-CFs) and azido-functionalized cellulose fibers (N3-CFs) was presented. Epoxy-cellulose fibers (Epoxy-CFs), graft copolymerization products of cellulose fibers (CFs) and glycidyl methacrylate (GMA), were prepared using cerium ammonium nitrate (CAN) as initiator. Epoxy groups content of Epoxy-CFs were as high as 2.5 mmol/g. Introduction of alkynyl/azido groups into Epoxy-CFs were achieved through ring-opening reactions of epoxy groups with propargylamine (PgAm) and sodium azide (NaN3), respectively. Under appropriate conditions, A-CFs with alkynyl groups of 0.57 mmol/g and N3-CFs with azido groups of 0.35 mmol/g were obtained. Click reactivities of A-CFs, N3-CFs and Epoxy-CFs were verified by Cu(I) catalyzed alkyne-azido cycloaddition (CuAAC) and thiol-epoxy click reactions. A-CFs, N3-CFs, Epoxy-CFs and their clicked products were characterized by attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS).

15.
Iran J Pharm Res ; 16(1): 50-62, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28496461

RESUMO

Angelica essential oil (AO), a major pharmacologically active component of Angelica sinensis (Oliv.) Diels, possesses hemogenesis, analgesic activities, and sedative effect. The application of AO in pharmaceutical systems had been limited because of its low oxidative stability. The AO-loaded gelatin-chitosan microcapsules with prevention from oxidation were developed and optimized using response surface methodology. The effects of formulation variables (pH at complex coacervation, gelatin concentration, and core/wall ratio) on multiple response variables (yield, encapsulation efficiency, antioxidation rate, percent of drug released in 1 h, and time to 85% drug release) were systemically investigated. A desirability function that combined these five response variables was constructed. All response variables investigated were found to be highly dependent on the formulation variables, with strong interactions observed between the formulation variables. It was found that optimum overall desirability of AO microcapsules could be obtained at pH 6.20, gelatin concentration 25.00%, and core/wall ratio 40.40%. The experimental values of the response variables highly agreed with the predicted values. The antioxidation rate of optimum formulation was approximately 8 times higher than that of AO. The in-vitro drug release from microcapsules was followed Higuchi model with super case-II transport mechanism.

16.
Am J Infect Control ; 44(11): 1285-1290, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27317404

RESUMO

OBJECTIVE: We aimed to fully describe epidemiologic characteristics, clinical manifestations, and clinical outcomes of Ebola virus disease (EVD), as well as detect independent factors significantly associated with mortality of the disease. METHODS: One hundred thirty-nine confirmed EVD patients enrolled at the JUI Holding and Treatment Centre in western Sierra Leone between November 15, 2014, and January 18, 2015, and demographic and clinical data were retrospectively collected and analyzed. RESULTS: The median age of investigated patients was 29 years and 55.4% were women. Of them, 76 patients (54.7%) died and 63 patients (45.3%) were cured. Case fatality rate among male patients was higher than in female patients (69.4% vs 42.9%). Fatigue (82.0%), anorexia (70.5%), abdominal pain (59.7%), diarrhea (58.3%), vomiting (56.1%), fever (55.4%), and muscle pain (54.0%) were the most common symptoms. In addition, 55.4% of investigated patients reported fever. Bleeding was seen in 10.8% of patients. CONCLUSIONS: Our data show that mortality of EVD is associated with an older age, fever, and probably hiccups.


Assuntos
Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/patologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Doença pelo Vírus Ebola/mortalidade , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Serra Leoa/epidemiologia , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
17.
Cell Mol Immunol ; 13(1): 103-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25726869

RESUMO

Complement 5a (C5a) has been implicated in the pathogenesis of sepsis by inducing the functional impairment of neutrophils; however, the utility of C5a receptors (C5aRs; C5aR and C5L2) as biomarkers for the management of sepsis is uncertain. This study investigated the dynamic expression of C5aR and C5L2 on neutrophils and their effects on neutrophil function. We found that sepsis patients displayed low expression levels of C5aR and C5L2 on neutrophils compared to healthy and systemic inflammatory response syndrome (SIRS) subjects, and this expression pattern was correlated with disease severity. Additionally, the expression levels of C5aR and C5L2 were associated with the survival of sepsis patients. In vitro, the addition of C5a significantly reduced C5aR and C5L2 expression levels and IL-8 production in neutrophils from sepsis patients. Those findings suggest that the reduced expression of C5aRs was associated with the functional impairment of neutrophils and a poor prognosis for sepsis patients. Overall, these findings may help establish C5aRs expression levels as early markers to predict the severity of sepsis.


Assuntos
Neutrófilos/imunologia , Receptor da Anafilatoxina C5a/imunologia , Receptores de Quimiocinas/imunologia , Sepse/imunologia , Adulto , Idoso , Biomarcadores/metabolismo , Estudos de Casos e Controles , Complemento C5a/imunologia , Complemento C5a/farmacologia , Feminino , Regulação da Expressão Gênica , Humanos , Interleucina-8/genética , Interleucina-8/imunologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/efeitos dos fármacos , Neutrófilos/patologia , Cultura Primária de Células , Prognóstico , Receptor da Anafilatoxina C5a/genética , Receptores de Quimiocinas/genética , Sepse/diagnóstico , Sepse/mortalidade , Sepse/patologia , Índice de Gravidade de Doença , Transdução de Sinais , Análise de Sobrevida , Resultado do Tratamento
18.
Int J Infect Dis ; 42: 34-39, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26523640

RESUMO

BACKGROUND: A Chinese medical team managed Ebola virus disease (EVD) patients in Sierra Leone from October 2014 to March 2015 and attended to 693 suspected patients, of whom 288 had confirmed disease. METHODS: A retrospective study was conducted of the 288 patients with confirmed disease. Clinical symptoms, manifestations, and serum viral load were analyzed and compared among the different groups for mortality and survival time. RESULTS: Among the 288 confirmed EVD patients (149 male and 139 female, median age 28 years, and median log viral load 6.68), 98 died, 36 recovered, and 154 were lost to follow-up. Common symptoms were fever (77.78%), fatigue (64.93%), abdominal pain (64.58%), headache (62.85%), and diarrhea (61.81%). Compared to patients aged<18 years, those who were older than 40 years had a higher probability of death (odds ratio 2.855, p=0.044). Patients with a viral load of >10(6) copies/ml had a higher case fatality rate than those with <10(6) copies/ml (odds ratio 3.095, p=0.004). Cox regression showed that age, viral load, and the presence of diarrhea correlated with mortality. CONCLUSION: Patients with a high viral load, of older age, and with diarrhea had a higher mortality and shorter survival time.


Assuntos
Doença pelo Vírus Ebola/mortalidade , Carga Viral , Adulto , Fatores Etários , Idoso , Diarreia/virologia , Ebolavirus/isolamento & purificação , Feminino , Doença pelo Vírus Ebola/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
19.
Int J Infect Dis ; 30: 57-63, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25461658

RESUMO

BACKGROUND: Sepsis encompasses two phases, the 'hyper'-reactive phase and the 'hypo'-reactive phase. The initial inflammatory stage is quickly counterbalanced by an anti-inflammatory response, which compromises the immune system, leading to immune suppression. Regulatory T cells (Tregs) have been implicated in the pathogenesis of sepsis by inducing immunosuppression; however, the role of CD39(+) Tregs in the process of sepsis is uncertain. This study investigated the dynamic levels of CD39(+) Tregs and their phenotypic change in sepsis. METHODS: Fourteen patients with systemic inflammatory response syndrome (SIRS), 42 patients with sepsis, and 14 healthy controls were enrolled. Sequential blood samples were used to analyze the numbers of CD39(+) Tregs and their phenotypic changes. Survival at 28 days was used to evaluate the capacity of CD39(+) Treg levels to predict mortality in sepsis patients. RESULTS: Sepsis patients displayed a high percentage (3.13%, 1.46%, and 0.35%, respectively) and mean fluorescence intensity (MFI) (59.65, 29.7, and 24.3, respectively) of CD39(+) Tregs compared with SIRS patients and healthy subjects. High-level expression of CD39(+) Tregs was correlated with the severity of sepsis, which was reflected by the sepsis-related organ failure assessment score (r=0.322 and r=0.31, respectively). In addition, the expression of CD39(+) Tregs was associated with survival of sepsis patients (p<0.01). By receiver-operating characteristic (ROC) curve analysis, the percentage and MFI of CD39(+) Tregs showed similar sensitivities and specificities to predict mortality (74.2% and 85.1%, and 73.9% and 84.1%, respectively). Using Kaplan-Meier curves to assess the impact of CD39(+) Tregs percentage and MFI on overall survival, we found that a high CD39(+) Tregs percentage (p<0.001; >4.1%) and MFI (p<0.001; >49.2) were significantly associated with mortality. Phenotypically, CD39(+) Tregs from sepsis patients showed high expression of CD38 and PD-1 (p<0.01 and p<0.01 respectively). CONCLUSIONS: Increased expression of CD39(+) Tregs was associated with a poor prognosis for sepsis patients, which suggests that CD39(+) Treg levels could be used as a biomarker to predict the outcome of sepsis patients.


Assuntos
Antígenos CD/análise , Apirase/análise , Sepse/mortalidade , Linfócitos T Reguladores/imunologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sepse/imunologia , Análise de Sobrevida , Síndrome de Resposta Inflamatória Sistêmica/imunologia , Síndrome de Resposta Inflamatória Sistêmica/mortalidade
20.
PLoS Negl Trop Dis ; 9(9): e0004113, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26398207

RESUMO

BACKGROUND: The Ebola virus causes an acute, serious illness which is often fatal if untreated. However, factors affecting the survival of the disease remain unclear. Here, we investigated the prognostic factors of Ebola virus disease (EVD) through various statistical models. METHODOLOGY/PRINCIPAL FINDINGS: Sixty three laboratory-confirmed EVD patients with relatively complete clinical profiles were included in the study. All the patients were recruited at Jui Government Hospital, Sierra Leone between October 1st, 2014 and January 18th, 2015. We first investigated whether a single clinical presentation would be correlated with the survival of EVD. Log-rank test demonstrated that patients with viral load higher than 10(6) copies/ml presented significantly shorter survival time than those whose viral load were lower than 10(6) copies/ml (P = 0.005). Also, using Pearson chi-square test, we identified that chest pain, coma, and viral load (>10(6) copies/ml) were significantly associated with poor survival of EVD patients. Furthermore, we evaluated the effect of multiple variables on the survival of EVD by Cox proportional hazards model. Interestingly, results revealed that patient's age, symptom of confusion, and viral load were the significantly associated with the survival of EVD cases (P = 0.017, P = 0.002, and P = 0.027, respectively). CONCLUSIONS/SIGNIFICANCE: These results suggest that age, chest pain, coma, confusion and viral load are associated with the prognosis of EVD, in which viral load could be one of the most important factors for the survival of the disease.


Assuntos
Ebolavirus/isolamento & purificação , Doença pelo Vírus Ebola/mortalidade , Adulto , Fatores Etários , Feminino , Doença pelo Vírus Ebola/diagnóstico , Doença pelo Vírus Ebola/epidemiologia , Humanos , Masculino , Prognóstico , Modelos de Riscos Proporcionais , Serra Leoa , Análise de Sobrevida , Carga Viral
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