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1.
Plants (Basel) ; 13(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38732464

RESUMEN

The enzymatic reaction stage (ECS) of oolong tea processing plays an important role in the formation of the flavor quality of the oolong tea. To investigate the dynamic changes in the volatile and non-volatile components in the leaves of oolong tea during the ECS, metabolomic studies were carried out using the leaf samples collected at different stages of the ECS of Aijiao oolong tea. Out of the identified 306 non-volatile metabolites and 85 volatile metabolites, 159 non-volatile metabolites and 42 volatile metabolites were screened out as key differential metabolites for dynamic changes during the ECS. A multivariate statistical analysis on the key differential metabolites showed that the accumulations of most metabolites exhibited dynamic changes, while some amino acids, nucleosides, and organic acids accumulated significantly after turning-over treatment. The evolution characteristics of 27 key precursors or transformed VOCs during the ECS of Aijiao oolong tea were clarified, and it was found that the synthesis of aroma substances was mainly concentrated in lipids as precursors and glycosides as precursor pathways. The results revealed the dynamic changes in the flavor metabolites in the ECS during the processing of Aijiao oolong tea, which provided valuable information for the formation of the characteristic flavor of Aijiao oolong tea.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38517080

RESUMEN

With the prevalence of human immunodeficiency virus type 1 (HIV-1) CRF01_AE and CRF07_BC subtypes in China, the co-circulation of multiple subtypes in the HIV-1-positive population may result in dual infection or superinfection in the population, leading to the emergence of unique recombinant forms (URFs) of the HIV-1 virus. In this study, two second-generation unique recombinant strains, BI0114 and BI0116, were identified, and their near full-length genome sequences were obtained. Recombination analysis showed that both sequences were isoforms of URF_0107, and they were second-generation unique recombinant strains formed by the recombination of CRF01_AE and CRF07_BC, with the isoforms being CRF01_AE and CRF0107_BC, respectively. The continued emergence of novel CRF01_AE/CRF07_BC recombinant strains suggests that the epidemiological, preventive, and control situation of HIV-1 is complex and that the relevant health authorities urgently need to establish responses to the challenges posed by changes in the pattern of strain recombination.

3.
iScience ; 27(3): 109114, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38375221

RESUMEN

Clarifying the accumulation and decomposition of soil organic carbon (SOC) is crucial for comprehending carbon cycling in terrestrial ecosystems. SOC enrichment and decomposition lead to the fractionation of stable carbon isotopes, a complex process influenced by various factors, including microbes. However, this fractionation process during early soil formation and the role of microorganisms remain poorly explored. This study investigated the relative composition of stable carbon isotopes (δ13C) of recently formed biological soil crusts (BSCs) on stabilized sand dunes in the Tengger Desert, Northern China. A notable increase in δ13C was observed during early BSC development, likely driven by cyanobacteria's direct fixation of CO2. Yet, δ13C values of BSCs gradually declined, approaching those of soils under native vegetation, probably linked to microbial succession within the BSCs. This finding highlights the potential microbial influence on early soil carbon turnover and underscores the effectiveness of isotope tracers for studying this process.

4.
ACS Nano ; 17(24): 25519-25531, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38061890

RESUMEN

Li metal exhibits high potential as an anode material for next-generation high-energy density batteries. However, the nonuniform transport of Li+ ions causes Li-dendrite growth at the metal electrode, leading to severe capacity decay and a short cycling life. In this study, negatively charged lithiophilic sites (such as cationic metal vacancies) were used as hosts to regulate the atomic-scale Li+-ion deposition in Li-metal batteries (LMBs). As a proof of concept, three-dimensional (3D) carbon nanofibers (CNFs) decorated with negatively charged TiNbO4 grains (labeled CNF/nc-TNO) were confirmed to be promising Li hosts. Cationic vacancies caused by the carbothermal reduction of Nb5+ and Ti4+ ions generated a negatively charged fiber surface and strong electrostatic interactions that guided the Li+-ion flux to the shadowed areas underneath the fiber and throughout the fibrous mat. Consequently, circumferential Li-metal plating was observed in the CNF/nc-TNO host, even at a high current density of 10 mA cm-2. Moreover, CNF/nc-TNO asymmetric cells delivered a significantly more robust and stable Coulombic efficiency (CE) (99.2% over 380 cycles) than cells comprising electrically neutral CNFs without cationic defects (which exhibits rapid failure after 20 cycles) or Cu foil (which exhibits rapid CE decay, with a CE of 87.1% after 100 cycles). Additionally, CNF/nc-TNO exhibited high stability and low-voltage hysteresis during repeated Li plating/stripping (for over 4000 h at 2 mA cm-2) with an areal capacity of 2 mAh cm-2. It was further paired with high-voltage LiNi0.8Co0.1Mn0.1 (NCM811) cathodes, and the full cells showed long-term cycling (220 cycles) with a CE of 99.2% and a steady rate capability.

5.
Plants (Basel) ; 12(24)2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38140429

RESUMEN

Understory planting affects the growth environment of tea plants, regulating the tea plant growth and the formation of secondary metabolites, which in turn affects the flavor of Xiaobai white tea. The present research adopted biochemical composition determination, widely targeted volatilities (WTV) analysis, multivariate statistical analysis, and odor activity value (OAV) analysis to analyze the characteristics in the macro-composition and volatile compounds of understory white tea. The sensory evaluation results indicated that understory Xiaobai white tea (LWTs) was stronger than ordinary Xiaobai white tea (PWTs) in terms of the taste of smoothness, sweetness, and thickness as well as the aromas of the flower and sweet. Understory planting reduced light intensity and air temperature, increased air humidity, organic matter, total nitrogen, and available nitrogen contents, which improved the growth environment of tea plants. The phytochemical analysis showed that the water-extractable substances, caffeine, flavonoids, and soluble sugar contents of understory tea fresh-leaf (LF) were higher than those of ordinary fresh-leaf (PF). The phytochemical analysis showed that the free amino acids, theaflavins, thearubigins, water-extractable substances, and tea polyphenols contents of LWTs were significantly higher than those of PWTs, which may explain the higher smoothness, sweetness, and thickness scores of LWTs than those of PWTs. The 2-heptanol, 2-decane, damasone, and cedar alcohol contents were significantly higher in LWTs than in PWTs, which may result in stronger flowery and sweet aromas in LWTs than in PWTs. These results provide a firm experimental basis for the observed differences in the flavor of LWTs and PWTs.

6.
Artículo en Inglés | MEDLINE | ID: mdl-37473535

RESUMEN

A multifunctional mixed-mode ß-CD polymer adsorbent PNVCD-SIM containing amphoteric ions and multiple functional groups was prepared. Its physicochemical properties were characterized by scanning electron microscope (SEM), 1H nuclear magnetic resonance (1H NMR), 13C NMR, Fourier transform infrared spectroscopy (FT-IR), nitrogen adsorption-desorption test, elemental analysis (EA), and thermogravimetry and differential scanning calorimetry (TGA-DSC). The acidic indomethacin and alkaline promethazine were selected to evaluate the adsorption properties of PNVCD-SIM at different pH. Under optimal neutral pH conditions, the adsorption performance of PNVCD-SIM on acidic NSAIDs, alkaline phenothiazine, and neutral steroid hormone drugs was investigated. The results showed that PNVCD-SIM exhibited excellent diversified adsorption properties for acidic, alkaline, and neutral mixed drug components through the synergistic effects of ß-CD inclusion, electrostatic interaction, hydrogen bond, π-π conjugation, and π-cation effect. The adsorption mechanism was consistent with the pseudo-second-order kinetic model and Langmuir isotherm model. Under the optimized conditions, a dispersive solid phase extraction method combined with high-performance liquid chromatography (dSPE-HPLC) using PNVCD-SIM as the adsorbent was established. The simultaneous extraction and detection of acidic-alkaline multi-component drugs in actual urine and lake water samples were successfully realized. This study provides new insight into the design and preparation of mixed-mode adsorption materials suitable for the rapid analysis and detection of multiple analytes.


Asunto(s)
Ácidos , Polímeros , Espectroscopía Infrarroja por Transformada de Fourier , Antiinflamatorios no Esteroideos , Extracción en Fase Sólida/métodos , Adsorción
7.
Opt Express ; 31(4): 6601-6614, 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36823912

RESUMEN

We propose a two-dimensional exit pupil expansion (2D-EPE) design of a diffractive waveguide (DW) based on polarization volume grating (PVG). The designed waveguide structure and pupil expansion principle are introduced in this paper. The light propagation behavior and available field of view (FoV) of the proposed waveguide are investigated by simulations. In addition, the waveguide sample based on the proposed design is prepared, and an imaging system based on a monochromatic MicroLED projector is built for AR imaging experiments. The experimental results show that the prepared waveguide system can achieve a clear AR display with a diagonal FoV of 30° and obtain an exit pupil magnification of nearly 20 times compared to the entrance pupil size. The optical imaging efficiency was measured to be 3.85%, and the backward light leakage rate was as low as 8.7%. This work further enhances the feasibility and practicality of the PVG-waveguide technology and provides a promising candidate for AR-DW applications.

8.
J Colloid Interface Sci ; 629(Pt B): 908-916, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36208603

RESUMEN

Silicon (Si), have been considered as promising anode material for lithium-ion batteries (LIBs), due to its high theoretical specific capacity of 4200 mAh g-1. However, the poor electrical conductivity and large volume change during lithiation/delithiation process, resulting in poor cycling stability, and seriously hindered the practical application in LIBs. Herein, a multiple Si/FexSiy@NC/CNTs composite is synthesized and investigated as advanced anode materials for LIBs via a simple one-step method. Such multiple Si/FexSiy@NC/CNTs composite has several merits including the FexSiy can not only accommodate the huge volume change of Si nanoparticles, but also enhance the conductivity upon discharge/charge process. Furthermore, the in-situ growth CNTs may help establish a long-range conductivity, and the Nitrogen-doped carbon (NC) layer can further improve the conductivity of Si, as well as inhibit the direct contract between electrolyte and Si during cycling process. Accordingly, the Si/FexSiy@NC/CNTs-1 exhibits excellent cycling stability (a high capacity of 994.4 mAh g-1 is maintained at 1.0 A g-1 after 600cycles) and outstanding rate capability (a suitable capacity of 441.7 mAh g-1 was obtained even at 5.0 A g-1). Moreover, the assembled full cell can achieve a capacity of 141.4 mAh g-1 after 65 cycles at 1.0C, exhibiting outstanding cycling stability. This work provides a prospective way for the commercial production of high-performance Si-based anode materials for LIBs.

9.
Opt Express ; 30(4): 6355-6364, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35209575

RESUMEN

Near-eye holographic waveguide display system using novel reflective polarized volume gratings (RPVG) have lately gotten a lot of interest. However, from polarization characteristics to imaging simulation, there is no systematic approach based on RPVG. Here, a full methodology for solving this problem using the rigorous coupled wave analysis (RCWA) model is presented. This self-built RCWA model is used to examine the optical behavior of RPVG. This excellent portability of the RCWA model makes it possible for RPVG as a diffractive optical element, which is integrated into the commercial optical software Zemax via a self-compiled dynamic link library (DLL), and a full-color imaging simulation of the based-RPVG waveguide display system is obtained. Our work provides an instructive imaging analysis method using the RPVG for holographic waveguide display.

10.
Sci Rep ; 12(1): 1708, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35105933

RESUMEN

Numerous studies have demonstrated that endothelial cell senescence plays a decisive role in the development and progression of cardiovascular diseases (CVD). Our previous results confirmed that Tetrahydroxy stilbene glycoside (TSG) can alleviate the human umbilical vein endothelial cells (HUVECs) senescence induced by H2O2 through SIRT1. It has been reported that miR-34a is a translational suppressor of SIRT1. In this study, we aimed to explore whether TSG regulates SIRT1 through miR-34a to ameliorate HUVECs senescence. H2O2 was used to induce premature senescence in HUVECs, and miR-34a mimic or inhibitor were transfected to over-express or suppress the expression level of miR-34a. Results revealed that TSG apparently decreased the miR-34a expression level in H2O2-induced premature senescence of HUVECs. When SIRT1 expression was inhibited by EX527, the attenuation of TSG on the expression level of miR-34a were abolished. When miR-34a expression was knockdown, the effect of TSG on HUVECs senescence could be enhanced. While miR-34a mimic could reverse the effect of TSG on HUVECs senescence. In conclusion, we demonstrated that TSG could attenuated endothelial cell senescence by targeting miR-34a/SIRT1 pathway.


Asunto(s)
Senescencia Celular/efectos de los fármacos , Glucósidos/farmacología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Peróxido de Hidrógeno/farmacología , MicroARNs/metabolismo , Transducción de Señal/efectos de los fármacos , Sirtuina 1/metabolismo , Estilbenos/farmacología , Carbazoles/farmacología , Células Cultivadas , Técnicas de Silenciamiento del Gen , Humanos , MicroARNs/genética , Transducción de Señal/genética , Sirtuina 1/antagonistas & inhibidores , Transfección
11.
J Pharm Biomed Anal ; 203: 114187, 2021 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-34111733

RESUMEN

A series of amino-derived mixed-mode chromatographic stationary phases were synthesized based on porous mercaptopropyl-functionalized polysilsesquioxane mesoporous microspheres synthesized by a co-condensation of methyltrimethoxysilane (MTMS) and mercaptopropyltrimethoxysilane (MPTMS). Through controlling the ratio of MTMS and MPTMS, the modified stationary phases with different amino densities were prepared by a "thiol-ene" click chemistry reaction. The morphology, pore structure, and functional groups of the microspheres were characterized by scanning electron microscope (SEM), nitrogen adsorption-desorption test, Fourier transform infrared spectroscopy (FT-IR), elemental analysis, and zeta potential, respectively. The chromatographic behavior of the stationary phases was evaluated by using alkylbenzene homologs and inorganic anions as probes. The mixed-mode retention behavior and separation mechanisms for neutral, alkaline, and acidic drugs on the prepared column had been systematically studied by changing the value of pH, ionic, and solvent strength of the mobile phase. Compared with the silica-based amino-bonded column (S-NH2), the synthesized organosilica phase exhibited higher hydrothermal stability and longer service life under high alkaline conditions. The newly synthesized phase was successfully applied to the simultaneous separation of the multiple substances in compound drugs.


Asunto(s)
Cromatografía de Fase Inversa , Preparaciones Farmacéuticas , Aniones , Interacciones Hidrofóbicas e Hidrofílicas , Microesferas , Compuestos de Organosilicio , Dióxido de Silicio , Espectroscopía Infrarroja por Transformada de Fourier
12.
ACS Nano ; 14(12): 17683-17692, 2020 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-33258364

RESUMEN

Transition-metal selenides have emerged as promising anode materials for sodium ion batteries (SIBs). Nevertheless, they suffer from volume expansion, polyselenide dissolution, and sluggish kinetics, which lead to inadequate conversion reaction toward sodium and poor reversibility during the desodiation process. Therefore, the transition-metal selenides are far from long cycling stability, outstanding rate performance, and high initial Coulombic efficiency, which are the major challenges for practical application in SIBs. Here, an efficient anode material including an FeSe2 core and N-doped carbon shell with inner void space as well as high conductivity is developed for outstanding rate performance and long cycle life SIBs. In the ingeniously designed FeSe2@NC microrods, the N-doped carbon shell can facilitate mass transport/electron transfer, protect the FeSe2 core from the electrolyte, and accommodate volume variation of FeSe2 with the help of the inner void of the core. Thus, the FeSe2@NC microrods can maintain strong structural integrity upon long cycling and ensure a good reversible conversion reaction of FeSe2 during the discharge/charge process. As a result, the as-prepared FeSe2@NC microrods exhibit excellent sodium storage performance and ultrahigh stability, achieving an excellent rate capability (411 mAh g-1 at 10.0 A g-1) and a long-term cycle performance (401.3 mAh g-1 after 2000 cycles at 5.0 A g-1).

13.
J Food Sci ; 85(8): 2589-2595, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32691409

RESUMEN

Time-temperature indicators (TTIs) can monitor the quality and safety of food. A new temperature-time point comparison method was proposed to match TTIs with food. This method omits the step of calculating activation energy (Ea ). It only compares the difference between TTI response time and food shelf life to determine their matching degree. Taking gold nanoparticle-based TTIs and muffins as experimental objects, the new and the traditional matching methods were used to match the absorbance of TTI and the peroxide value of muffins. The two results are not significantly different. TTIs with gelatin solution and gold precursor solution concentration of 150.00  and 2.05 mg/mL, respectively, can show the quality of muffins. TTIs changed from light yellow to pink and finally appeared deep purple. The deep purple represented spoilage and inedibility of muffins. Comparing Ea of food and that of TTIs can preliminarily evaluate their matching degree, improving the experiment efficiency. Hence, it is reasonable to use the traditional matching method in most cases, and use the new method only when Ea of food cannot be obtained. PRACTICAL APPLICATION: The deterioration rate of food is usually calculated by developing kinetic models of characteristic quality parameters. When the reaction rate is unavailable or inaccurate, the activation energy of food cannot be obtained. In this case, it is impossible to match TTIs with food based on the traditional method. This research develops a new matching method and helps TTIs and food to be matched without considering activation energy. It will promote the application of TTIs in more products.


Asunto(s)
Pan/análisis , Almacenamiento de Alimentos/métodos , Oro/química , Nanopartículas del Metal/química , Almacenamiento de Alimentos/instrumentación , Cinética , Control de Calidad , Temperatura , Factores de Tiempo
14.
Sci Total Environ ; 718: 137329, 2020 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-32105925

RESUMEN

Sediment adsorption is one of the main fates of antibiotics in aquatic environments. However, few studies have compared the physicochemical properties of sediments from the same aquatic ecosystem but at different locations and correlated them with antibiotic adsorption efficiency. To predict the adsorption of antibiotics in water-sediment systems more accurately, this study conducted experiments with tetracycline (TC) and oxytetracycline (OTC) in tetracyclines, ciprofloxacin (CIP) in fluoroquinolones, and roxithromycin (ROX) in macrolides. Sediments from different locations in Lake Taihu, China, were collected to determine the adsorption properties of CIP, TC, OTC, and ROX. Moreover, the physicochemical properties of the sediments were measured and the correlation between these properties and antibiotic adsorption were discussed to establish a model for predicting adsorption parameter Kd. The antibiotic adsorption performance of sediments was high in heavily polluted and grassy areas but poor in estuarine areas of the lake, suggesting that adsorption effectiveness was affected by the physicochemical properties of sediments. Based on the established model, the specific surface area, organic carbon, and cation exchange capacity played the most significant roles. The study further determined that the predicted and actual values showed a good linear fitting relationship. Therefore, the model effectively predicted the antibiotic adsorption performance of different sediments and provided recommendations for the environmental trend and risk assessment of antibiotics.


Asunto(s)
Lagos , Adsorción , Antibacterianos , China , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Contaminantes Químicos del Agua
15.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 32(7): 959-967, 2018 07 15.
Artículo en Chino | MEDLINE | ID: mdl-30129324

RESUMEN

Objective: To investigate the mechanical properties of the novel compound calcium phosphate cement (CPC) biological material as well as the biological activity and osteogenesis effects of induced pluripotent stem cells (iPS) seeding on scaffold and compare their bone regeneration efficacy in cranial defects in rats. Methods: Ac- cording to the different scaffold materials, the experiment was divided into 4 groups: pure CPC scaffold group (group A), CPC∶10% wt chitosan as 2∶1 ratio mixed scaffold group (group B), CPC∶10% wt chitosan∶whisker as 2∶1∶1 ratio mixed scaffold group (group C), and CPC∶10% wt chitosan∶whisker as 2∶1∶2 ratio mixed scaffold group (group D). Mechanical properties (bending strength, work-of-fracture, hardness, and modulus of elasticity) of each scaffold were detected. The scaffolds were cultured with fifth generation iPS-mesenchymal stem cells (MSCs), and the absorbance ( A) values of each group were detected at 1, 3, 7, and 14 days by cell counting kit 8 (CCK-8) method; the alkaline phosphatase (ALP) activity, Live/Dead fluorescence staining and quantitative detection, ALP, Runx2, collagen typeⅠ, osteocalcin (OC), and bone morphogenetic protein 2 (BMP-2) gene expressions by RT-PCR were detected at 1, 7, and 14 days; and the alizarin red staining were detected at 1, 7, 14, and 21 days. Twenty-four 3-month-old male Sprague Dawley rats were used to establish the 8 mm-long skull bone defect model, and were randomly divided into 4 groups ( n=6); 4 kinds of scaffold materials were implanted respectively. After 8 weeks, HE staining was used to observe the repair of bone defects and to detect the percentage of new bone volume and the density of neovascularization. Results: The bending strength, work-of-fracture, hardness, and modulus of elasticity in groups B, C, and D were significantly higher than those in group A, and in groups C, D than in group B, and in group D than in group C ( P<0.05). CCK-8 assay showed that cell activity gradually increased with the increase of culture time, the A values in groups B, C, and D at 3, 7, 14 days were signifiantly higher than those in group A, and in groups C, D than in group B ( P<0.05), but no significant difference was found between groups C and D ( P>0.05). Live/Dead fluorescence staining showed that the proportion of living cells in groups B, C, and D at 7 and 14 days was significantly higher than that in group A ( P<0.05), and in groups C, D at 7 days than in group B ( P<0.05); but no significant difference was found between groups C and D ( P>0.05). RT-PCR showed that the relative expressions of genes in groups B, C, and D at 7 and 14 days were significantly higher than those in group A, and in groups C, D than in group B ( P<0.05); but no significant difference was found between groups C and D ( P>0.05). Alizarin red staining showed that the red calcium deposition on the surface of scaffolds gradually deepened and thickened with the prolongation of culture time; the A values in groups B, C, and D at 14 and 21 days were significantly higher than those in group A ( P<0.05), and in groups C and D than in group B ( P<0.05), but no significant difference was found between groups C and D ( P>0.05). In vivo repair experiments in animals showed that the new bone in each group was mainly filled with the space of scaffold material. Osteoblasts and neovascularization were surrounded by new bone tissue in the matrix, and osteoblasts were arranged on the new bone boundary. The new bone in groups B, C, and D increased significantly when compared with group A, and the new bone in groups C and D was significantly higher than that in group B. The percentage of new bone volume and the density of neovascularization in groups B, C, and D were significantly higher than those in group A, and in groups C and D than in group B ( P<0.05); but no significant difference was found between groups C and D ( P>0.05). Conclusion: The mechanical properties of the new reinforced composite scaffold made from composite chitosan, whisker, and CPC are obviously better than that of pure CPC scaffold material, which can meet the mechanical properties of cortical bone and cancellous bone. iPS-MSCs is attaching and proliferating on the new reinforced composite scaffold material, and the repair effect of bone tissue is good. It can meet the biological and osteogenic activity requirements of the implant materials in the bone defect repair.


Asunto(s)
Materiales Biocompatibles , Quitosano , Células Madre Pluripotentes Inducidas , Osteogénesis , Ingeniería de Tejidos , Animales , Fosfatos de Calcio , Diferenciación Celular , Células Cultivadas , Masculino , Ratas , Ratas Sprague-Dawley , Andamios del Tejido , Vibrisas
16.
Exp Ther Med ; 15(6): 5403-5409, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29904419

RESUMEN

Serum procalcitonin (PCT) levels may be helpful for the diagnosis of infections during the perioperative period of arthroplasty. However, there is much debate in the literature regarding the appropriate cut-off value for different types of surgery and local bacterial infection. The present study aimed to evaluate serum PCT levels in patients undergoing arthroplasty and to determine the cut-off value that may represent perioperative pneumonia, urinary infections and superficial surgical site infections. The present retrospective study included a total of 500 patients treated between July 2014 and August 2015. The case group contained 25 patients with perioperative infections (pneumonia, urinary and superficial surgical site infections), and the control group contained 25 patients without any post-surgical complications. Serum levels of PCT and white blood cells (WBC) were measured pre-operatively (D0) and at post-operative D4, D6 and D8, and the sensitivity, specificity and predictive value of these parameters were assessed. Regarding the comparison of the mean PCT levels between the case and the control group, a significant difference was seen at D8 (P=0.007), while no significant differences were observed at D0 (P=0.010), D4 (P=0.069) and D6 (P=0.093). No statistically significant differences in WBC levels between groups were observed for (P>0.01). In the control group, the PCT levels at D4 (0.062±0.020 ng/ml) were 2-fold of the mean baseline value, followed by a decrease until D6 (0.051±0.019 ng/ml) and a return close to the normal range by D8 (0.032±0.015 ng/ml). The PCT levels in the case group had rapidly increased on D4 (0.510±1.208 ng/ml). In contrast to the control group, they continuously increased on D6 (0.527±1.360 ng/ml) and D8 (0.686±1.117 ng/ml). From a clinical point of view, infection events were indicated in these patients during post-operative follow-up. For PCT, the area under the receiver operating characteristic curve (AUC) was 0.978 [95% confidence interval (CI), 0.933-1.022], and for WBC, the AUC was 0.562 (95% CI, 0.398-0.0.726). Based on the above data, the PCT value was a significant predictor of infection (AUC>0.9). For PCT, the cut-off point of 0.0995 ng/ml was associated with a sensitivity of 96% and a specificity of 100%. However, WBC were not a significant predictor of infection (0.5

17.
BMC Health Serv Res ; 17(1): 128, 2017 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-28187728

RESUMEN

BACKGROUND: Despite considerable efforts to encourage participation, even in some developed countries, proportion of patients participating in institution-based cardiac rehabilitation (CR) programs remained sub-optimal. The present study was designed to investigate the acceptability of community health service center (CHSC)-based Cardiac Rehabilitation (CR), and examine its effectiveness in terms of changes in quality of life (QOL), psychological state and exercise capacity. METHODS: A consecutive series of eligible patients was recruited from the health registration system of two CHSCs in Shijiazhuang, Hebei, China. Patients in intervention site were provided with CR (CR-group) while patients in non-intervention site were offered the usual care (UC-group). Data regarding health-related QOL (HRQoL), psychological state and exercise capacity (6-min walk test = 6MWT) were collected and compared at baseline and at 6 months post-intervention. RESULTS: Among invited patients eligible for CR program, 65.3% participated, while 5.3% of the participants dropped out during follow-up. Patients in CR-group showed significant decrease in the scores for anxiety and depression as per the Hospital Anxiety and Depression Scale (HADS), along with marked increases in the Short-Form Health Survey (SF-12)-based Physical (PCS) and Mental Component Summary (MCS) scores. Moreover, the measurement of 6MWT showed a significant increase of 57.42 m walking distance among CR patients in contrast with a slight increase among UC patients. CONCLUSIONS: Given the high participation and low withdrawal along with considerable improvements in HRQoL, psychological state and exercise capacity, CHSC was likely to be the optimal setting for implementing CR for patients with CHD in China. TRIAL REGISTRATION: ChiCTR-TRC- 12002500 . Registered 16 September 2012.


Asunto(s)
Rehabilitación Cardiaca , Servicios de Salud Comunitaria , Enfermedad de la Arteria Coronaria , Anciano , Ansiedad , China , Depresión , Trastorno Depresivo , Ejercicio Físico , Terapia por Ejercicio , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Calidad de Vida , Encuestas y Cuestionarios
18.
Zhongguo Zhong Yao Za Zhi ; 39(10): 1795-8, 2014 May.
Artículo en Chino | MEDLINE | ID: mdl-25282884

RESUMEN

In this study, the processes of pollination ecology of Fritillaria delavayi were investigated to document its reproductive characteristics. Some individuals of F. delavayi could produce seeds under bagging without emasculation (11%), but the rate was significantly lower than that of the natural control (87%). It is suggesting that pollination of F. delavayi largely depends on pollen vectors. Bombus sushikini was the only effective pollinator of F. delavayi and the visitation frequency was 0.003 time xXflower(-1) x min(-1). Flowering of F. delavayi in whole population lasted for 35 d and single flower for 11 d. Pollen viability and stigma receptivity lasted for 9 d and were relatively long compared with other Fritillaria genus plants. Consequently, bumblebee pollination and long floral longevity seem to be important for reproductive assurance of F. delavayi in harsh alpine environments.


Asunto(s)
Abejas/fisiología , Fritillaria/fisiología , Polen/fisiología , Polinización , Animales
19.
Cyberpsychol Behav Soc Netw ; 15(6): 312-7, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22703037

RESUMEN

Referred to as "Weibo," microblogging in China has witnessed an exponential growth. In addition to the Twitter-like functionality, Weibo allows rich media uploads into user feeds, provides threaded comments, and offers applications, games, and Weibo medals. This expanded functionality, as well as the observed differences in trending content, suggests potentially different user motivations to join Weibo and their usage patterns compared to Twitter. This pioneering study identifies dominant Weibo user motivations and their effects on usage patterns. We discuss the findings of an online survey of 234 Weibo users and suggest managerial implications and future research directions.


Asunto(s)
Blogging , Motivación , Red Social , Adolescente , Adulto , China , Femenino , Humanos , Masculino , Persona de Mediana Edad
20.
Cyberpsychol Behav ; 11(6): 727-9, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18991530

RESUMEN

This study explored Internet addiction among university students in China and the United States to develop a better understanding of Internet addiction in a cross-national setting. Three hundred fourteen respondents were evaluated on 10 Internet addiction symptoms and five Internet addiction dimensions: negative outcomes, social escape, secretive behavior, virtual intimacy, and obsessive-compulsive behavior. The results indicate that Chinese students experience a higher rate of Internet addiction than their U.S. counterparts. Additionally, gender was found to be significantly related to Internet addiction for both the U.S. and Chinese sample, while Internet experience was found to not be significantly related to Internet addiction. We conclude that Internet addiction may result as an artifact of the stage of Internet adoption within a society.


Asunto(s)
Conducta Adictiva/epidemiología , Internet/estadística & datos numéricos , Conducta Adictiva/psicología , China/epidemiología , Confidencialidad , Reacción de Fuga , Femenino , Humanos , Masculino , Estados Unidos/epidemiología , Adulto Joven
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