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1.
JMIR Aging ; 6: e46791, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37986117

RESUMEN

Background: Identifying persons with a high risk of developing osteoporosis and preventing the occurrence of the first fracture is a health care priority. Most existing osteoporosis screening tools have high sensitivity but relatively low specificity. Objective: We aimed to develop an easily accessible and high-performance preclinical risk screening tool for osteoporosis using a machine learning-based method among the Hong Kong Chinese population. Methods: Participants aged 45 years or older were enrolled from 6 clinics in the 3 major districts of Hong Kong. The potential risk factors for osteoporosis were collected through a validated, self-administered questionnaire and then filtered using a machine learning-based method. Bone mineral density was measured with dual-energy x-ray absorptiometry at the clinics; osteoporosis was defined as a t score of -2.5 or lower. We constructed machine learning models, including gradient boosting machines, support vector machines, and naive Bayes, as well as the commonly used logistic regression models, for the prediction of osteoporosis. The best-performing model was chosen as the final tool, named the Preclinical Osteoporosis Screening Tool (POST). Model performance was evaluated by the area under the receiver operating characteristic curve (AUC) and other metrics. Results: Among the 800 participants enrolled in this study, the prevalence of osteoporosis was 10.6% (n=85). The machine learning-based Boruta algorithm identified 15 significantly important predictors from the 113 potential risk factors. Seven variables were further selected based on their accessibility and convenience for daily self-assessment and health care practice, including age, gender, education level, decreased body height, BMI, number of teeth lost, and the intake of vitamin D supplements, to construct the POST. The AUC of the POST was 0.86 and the sensitivity, specificity, and accuracy were all 0.83. The positive predictive value, negative predictive value, and F1-score were 0.41, 0.98, and 0.56, respectively. Conclusions: The machine learning-based POST was conveniently accessible and exhibited accurate discriminative capabilities for the prediction of osteoporosis; it might be useful to guide population-based preclinical screening of osteoporosis and clinical decision-making.

2.
Phytomedicine ; 110: 154643, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36623444

RESUMEN

BACKGROUND: Skin aging is associated with degradation of collagen by matrix metalloproteinases (MMPs), which leads to loss of skin elasticity and formation of wrinkles. Cosmos caudatus Kunth (CC) has been traditionally claimed as an anti-aging agent in Malaysia. Despite its well-known antioxidant activity, the anti-aging properties of CC was not validated. PURPOSE: This study aimed to investigate the anti-aging potential of CC extracts and fractions, particularly their inhibition of collagenase, MMP-1 and MMP-3 activities in human dermal fibroblasts CCD-966SK, followed by isolation, identification and analysis of their bioactive constituents. STUDY DESIGN AND METHODS: DPPH assay was firstly used to evaluate the antioxidant activity throughout the bioactivity-guided fractionation. Cell viability was determined using MTS assay. Collagenase activity was examined, while MMP-1 and MMP-3 expression were measured using qRT-PCR and western blotting. Then, chemical identification of pure compounds isolated from CC fractions was done by using ESIMS, 1H and 13C NMR spectroscopies. HPLC analyses were carried out for bioactive fractions to quantify the major components. RESULTS: Throughout the antioxidant activity-guided fractionation, fractions CC-E2 and CC-E3 with antioxidant activity and no toxicity towards CCD-966SK cells were obtained from CC 75% ethanol partitioned layer (CC-E). Both fractions inhibited collagenase activity, MMP-1 and MMP-3 mRNA and protein expression, as well as NF-κB activation induced by TNF-α in CCD-966SK cells. 14 compounds, which mainly consists of flavonoids and their glycosides, were isolated. Quercitrin (14.79% w/w) and quercetin (11.20% w/w) were major compounds in CC-E2 and CC-E3, respectively, as quantified by HPLC. Interestingly, both fractions also inhibited the MMP-3 protein expression synergistically, compared with treatment alone. CONCLUSION: The quantified CC fractions rich in flavonoid glycosides exhibited skin anti-aging effects via the inhibition of collagenase, MMP-1 and MMP-3 activities, probably through NF-κB pathway. This is the first study reported on MMP-1 and MMP-3 inhibitory activity of CC with its chemical profile, which revealed its potential to be developed as anti-aging products in the future.


Asunto(s)
Metaloproteinasa 1 de la Matriz , Envejecimiento de la Piel , Humanos , Metaloproteinasa 1 de la Matriz/genética , Antioxidantes/farmacología , Antioxidantes/metabolismo , FN-kappa B/metabolismo , Metaloproteinasa 3 de la Matriz/metabolismo , Colagenasas/metabolismo , Colagenasas/farmacología , Piel , Flavonoides/farmacología , Envejecimiento , Glicósidos/farmacología , Fibroblastos
3.
Front Public Health ; 10: 1000594, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36582390

RESUMEN

Background: Tai Chi has been broadly applied as alternative treatment for many neurological and psychological disorders. Whereas no study using Tai Chi as prophylactic treatment for migraine. The purpose of this study was to preliminarily examine the efficacy and feasibility of a 12-week Tai Chi training on migraine attack prevention in a sample of Chinese women. Methods: A two-arm randomized controlled trial was designed. Women aged 18 to 65 years and diagnosed with episodic migraine were randomized to either Tai Chi group (TC group) or the waiting list control group. A modified 33-short form Yang-style Tai Chi training with 1 h per day, 5 days per week for 12 weeks was implemented in the TC group, with a 12-week follow up period. The control group received a "delayed" Tai Chi training at the end of the trial. The primary outcome was the differences in attack frequency between 4 weeks before baseline and at the 9-12 weeks after randomization. The intensity and duration of headache were also measured. The feasibility was evaluated by the maintenance of Tai Chi practice and satisfactory level of the participants toward training. Results: Eighty-two women were randomized, finally 40 in TC group and 33 in control group were involved in the analysis. On average, women in TC group had 3.0 times (95% CI: -4.0 to -2.0, P < 0.01) and 3.6 days (95% CI: -4.7 to -2.5, P < 0.01) reduction of migraine attack per month. Compared with the control group, the differences were statistically significant (-3.7 attacks/month, 95% CI: -5.4 to -1.9; and -3.0 migraine days/month, 95% CI: -4.5 to -1.5; both P < 0.001). The intensity and duration of headache had 0.6 (95% CI: -1.2 to -0.0, P < 0.05) units and 1.2 (IQR: -5.0 to 1.1, P < 0.05) hours reduction in TC group, respectively. Most of the participants (69.2%-97.4%) were satisfied with the training. At the end of 24 weeks, on average, the participants maintained 1.5 times of practice per week and 20 min for each practice. Conclusion: The 12-week Tai Chi training significantly decreased the frequency of migraine attack. It was acceptable and practicable among female migraineurs. Clinical trial registration: www.ClinicalTrials.gov, identifier: NCT03015753.


Asunto(s)
Trastornos Migrañosos , Taichi Chuan , Humanos , Femenino , Hong Kong , Pueblos del Este de Asia , Estudios de Factibilidad , Trastornos Migrañosos/prevención & control , Cefalea
4.
Mitochondrial DNA B Resour ; 7(8): 1528-1530, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36034532

RESUMEN

Bauhinia racemosa Lam. (1783), a versatile medicinal plant, belongs to the family Fabaceae (subfamily Cercidoideae). In this study, we analyzed the complete chloroplast genome to facilitate its use in genetic research. The complete chloroplast genome of B. racemosa was found to be 155,501 bp long, including two inverted repeat (IR) regions of 25,446 bp, which are separated by a small single-copy (SSC) region of 18,295 bp and a large single-copy (LSC) region of 86,314 bp. The overall GC content is 36.4%. The genome of B. racemosa contains 129 genes, including 83 protein-coding genes, 37 tRNAs, 8 rRNAs, and 1 pseudogene (rps19). Phylogenetic analysis suggests that B. racemosa forms a monophyletic clade with the other four Bauhinia species (B. brachycarpa, B. purpurea, B. blakeana and B. variegata var. variegata).

5.
J Nucl Med ; 63(4): 556-559, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34475235

RESUMEN

This prospective nonrandomized, multicenter clinical trial was performed to investigate the efficacy and safety of 131I-labeled metuximab in adjuvant treatment of unresectable hepatocellular carcinoma. Methods: Patients were assigned to treatment with transcatheter arterial chemoembolization (TACE) combined with 131I-metuximab or TACE alone. The primary outcome was overall tumor recurrence. The secondary outcomes were safety and overall survival. Results: The median time to tumor recurrence was 6 mo in the TACE + 131I-metuximab group (n = 160) and 3 mo in the TACE group (n = 160) (hazard ratio, 0.55; 95% CI, 0.43-0.70; P < 0.001). The median overall survival was 28 mo in the TACE + 131I-metuximab group and 19 mo in the TACE group (hazard ratio, 0.62; 95% CI, 0.47-0.82; P = 0.001). Conclusion: TACE + 131I-metuximab showed a greater antirecurrence benefit, significantly improved the 5-y survival of patients with advanced hepatocellular carcinoma, and was well tolerated by patients.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Anticuerpos Monoclonales , Carcinoma Hepatocelular/patología , Quimioembolización Terapéutica/efectos adversos , Terapia Combinada , Arteria Hepática/patología , Humanos , Radioisótopos de Yodo , Neoplasias Hepáticas/patología , Recurrencia Local de Neoplasia , Estudios Prospectivos , Resultado del Tratamiento
6.
Nat Prod Res ; 36(12): 3043-3053, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34498976

RESUMEN

Juncus effusus L. (J. effusus) is a Traditional Chinese Medicine (TCM) that has long been used for dealing with gynaecological disorders, such as relieving insomnia, preventing tinnitus, reducing edema with diuretic effect. In our course of evidence-based medical research focused on this herb, one new phenanthrene, Junfusol B (2), together with seventeen known compounds were isolated and identified. All the structures of these compounds were elucidated by spectroscopic methods. The absolute stereochemistry of compounds 1 and 2 was further determined by comparing their calculated and experimental Electronic Circular Dichroism (ECD) spectra and optical rotation (OR) values. The isolates were evaluated for their estrogenic and anti-inflammatory activities which were considered as relevant etiological factors of insomnia, tinnitus and edema in the ancient TCM theory. The results revealed that most of the obtained phenanthrenes in this work were found exerting agonistic effects on estrogen receptor. This is the first report to declare the exact estrogen-regulating potential among this type of compounds from J. effusus. Moreover, phenanthrenes 3 - 7 exhibited significant inhibitions on superoxide anion generation and elastase release in fMLP/CB-induced human neutrophilic inflammation model. J. effusus may be developed as a complementary agent utilized in menopausal multiple syndromes.


Asunto(s)
Magnoliopsida , Fenantrenos , Trastornos del Inicio y del Mantenimiento del Sueño , Acúfeno , Antiinflamatorios/química , Antiinflamatorios/farmacología , Edema , Humanos , Magnoliopsida/química , Fenantrenos/química , Fenantrenos/farmacología
7.
Front Pharmacol ; 12: 785944, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34867418

RESUMEN

Adlay (Coix lacryma-jobi var. ma-yuen (Rom. Caill.) Stapf) seeds are edible crop classified as Traditional Chinese Medicine (TCM). Adlay bran (AB) is one of the wastes generated during adlay refining processes. In this work, supercritical fluid extract of AB (AB-SCF) was investigated to reveal its lipid regulating potential and decode its bifunctional ingredients. AB-SCF×0.5 (30.84 mg/kg/body weight), AB-SCF×1 (61.67 mg/kg/BW), AB-SCF×5 (308.35 mg/kg/BW) and AB-SCF×10 (616.70 mg/kg/BW) were administrated to high fat-diet (HFD) induced hyperglycemic hamsters for 8 weeks. The results indicates that AB-SCF displays a prevention of dramatic body weight gains, lower levels of serum TG, TC, LDL-C and higher in HDL-C, amelioration of cardiovascular risk, alleviation of hepatic TG, TC and lipid peroxidation, and enhancement on cholesterol metabolism with higher bile acid excretion. Investigations on energy metabolic mechanism demonstrates that the hyperlipidemia mitigating capacities of AB-SCF are up-regulated on lipoprotein lipase, AMPK, p-AMPK and down-regulated at fatty acid synthase. Major bio-functional lipid compositions are identified as linoleic acid (28.59%) and oleic acid (56.95%). Non-lipid chemical and active markers are confirmed as 3-O-(trans-4-feruloyl)-ß-sitostanol (1463.42 ppm), 3-O-(cis-4-feruloyl)-ß-sitostanol (162.60 ppm), and ß-sitosterol (4117.72 ppm). These compositions might synergistically responsible for the mentioned activities and can be regarded as analytical targets in quality control. AB-SCF may be considered as a promising complementary supplement, and developed as a functional food or new botanical drug in the future.

8.
J Agric Food Chem ; 69(40): 11856-11866, 2021 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-34590863

RESUMEN

Four active partition layers and ten isolates, including (5R)- and (5S)-macapyrrolidone A (1a, 1b), and four new alkaloids, (5R)- and (5S)-macapyrrolidone B (2a, 2b) and macapyrrolins D, E (3, 4), were isolated from maca (Lepidium meyenii Walp.), an indigenous food plant from Peru. Derived from the n-hexane layer, the macamide-rich fraction exhibited pro-angiogenic activity on EPC and HUVEC cells. Anti-thrombotic activity was displayed by the polar part of maca extracts (n-butanol and water layers). Both 75% methanol aq. (midlower polar part) and n-hexane (low polar part) layers, which showed signs of fatty acid content, markedly inhibited superoxide and elastase release in an anti-inflammatory assay. The 75% methanol aq. layer showed strong anti-allergic activity, and macapyrrolin A (5) was found active based on ß-hexosaminidase release inhibition assays and a ChemGPS-NP experiment. These valuable bioactivity results suggest that maca is a food plant with good benefits for human health.


Asunto(s)
Alcaloides , Antialérgicos , Lepidium , Antiinflamatorios/farmacología , Humanos , Extractos Vegetales/farmacología
10.
BMC Health Serv Res ; 19(1): 995, 2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31878946

RESUMEN

BACKGROUND: The number of Chinese migrants in Sub-Saharan Africa (SSA) is increasing, which is part of the south-south migration. The healthcare seeking challenges for Chinese migrants in Africa are different from local people and other global migrants. The aim of this study is to explore utilization of local health services and barriers to health services access among Chinese migrants in Kenya. METHODS: Thirteen in-depth interviews (IDIs) and six focus group discussions (FGDs) were conducted among Chinese migrants (n = 32) and healthcare-related stakeholders (n = 3) in Nairobi and Kisumu, Kenya. Data was collected, transcribed, translated, and analyzed for themes. RESULTS: Chinese migrants in Kenya preferred self-treatment by taking medicines from China. When ailments did not improve, they then sought care at clinics providing Traditional Chinese Medicine (TCM) or received treatment at Kenyan private healthcare facilities. Returning to China for care was also an option depending on the perceived severity of disease. The main supply-side barriers to local healthcare utilization by Chinese migrants were language and lack of health insurance. The main demand-side barriers included ignorance of available healthcare services and distrust of local medical care. CONCLUSIONS: Providing information on quality healthcare services in Kenya, which includes Chinese language translation assistance, may improve utilization of local healthcare facilities by Chinese migrants in the country.


Asunto(s)
Utilización de Instalaciones y Servicios/estadística & datos numéricos , Migrantes/psicología , Adulto , China/etnología , Femenino , Accesibilidad a los Servicios de Salud , Humanos , Kenia , Masculino , Persona de Mediana Edad , Investigación Cualitativa , Migrantes/estadística & datos numéricos
11.
Phytochemistry ; 162: 39-46, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30852259

RESUMEN

Qing Dai (Naturalis Indigo) is a traditional Chinese medicine (TCM) used as a topical agent in moderate psoriasis, targeting interleukin-17 (IL-17). In this study, it was prepared from the aerial parts of Strobilanthes cusia. Three undescribed indole alkaloid derivatives, indigodoles A-C, along with seven known compounds were isolated from this preparation of Qing Dai and their structures were elucidated from spectroscopic data, including NMR, MS, UV, IR, optical rotation, and CD. As well, most compounds were tested against IL-17. Indigodole C and tryptanthrin could significantly inhibit IL-17 production of Th17 cells. In addition, indigodole A and indirubin showed notably anti-IL-17 gene expression in dose-dependent effects without cytotoxicities toward Th17 and Jurkat cells, respectively. Overall, our studies indicate that the aforementioned indole alkaloids could contribute to anti-IL 17 properties of Qing Dai.


Asunto(s)
Acanthaceae/química , Medicamentos Herbarios Chinos/química , Alcaloides Indólicos/química , Alcaloides Indólicos/farmacología , Interleucina-17/antagonistas & inhibidores , Medicina Tradicional China , Componentes Aéreos de las Plantas/química , Animales , Interleucina-17/biosíntesis , Ratones , Modelos Moleculares , Conformación Molecular , Células Th17/efectos de los fármacos , Células Th17/metabolismo
12.
Fitoterapia ; 130: 125-133, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30149097

RESUMEN

Six new diterpenes, leojaponins G-L (1-6) along with 19 known compounds (7-25) were isolated from Leonurus japonicus. Their structures were elucidated by NMR, MS, IR, UV, and ECD spectroscopic data. Anti-melanogenesis assay indicated that 7 could safely and dose-dependently decrease melanin production in B16F10 melanoma cell with an IC50 value of 59.1 µM, but moderately inhibit tyrosinase activity. Without cytotoxicities at 20 µM, compounds 11, 14, 15, and 17-21 showed significant melanogenesis stimulation activities at the percentages of 7.7-48.2. Antioxidants 19 and 24 could notably inhibit ROS production in a dose-dependent manner with percentages of 24.7-42.2 and 27.9-40.2, respectively among the concentrations of 0.16 to 100 µM. Our results demonstrated L. japonicus and its constituents could be potential botanical resources of cosmeceutical development for treatment and prevention of skin disorders.


Asunto(s)
Diterpenos/farmacología , Leonurus/química , Animales , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Células Cultivadas , Diterpenos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacología , Humanos , Queratinocitos/efectos de los fármacos , Melanoma Experimental , Ratones , Estructura Molecular , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Componentes Aéreos de las Plantas/química , Especies Reactivas de Oxígeno/metabolismo , Taiwán
14.
Dig Liver Dis ; 47(1): 24-9, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25308612

RESUMEN

BACKGROUND: Asymptomatic erosive esophagitis by definition is a condition lacking any reflux symptom. AIMS: We aimed to investigate the prevalence of asymptomatic erosive esophagitis in a general population undergoing periodic health checkup. METHODS: Consecutive subjects undergoing a medical checkup were enrolled for evaluation of reflux disease with upper endoscopy and a validated reflux questionnaire. The presence and severity of erosive esophagitis were evaluated. In all subjects, demographic characteristics and biochemical data were recorded, and sleep and psychological characteristics were assessed by means of self-administered Pittsburgh Sleep Quality Index score, Taiwanese Depression Questionnaire score, and State-Trait Anxiety Inventory score. RESULTS: Of 2568 subjects eligible for this study, erosive esophagitis was found in 676 subjects (26.3%), in whom the proportions of asymptomatic and symptomatic erosive esophagitis were 59.2% (400 subjects) and 40.8% (276 subjects) respectively. At a univariate analysis, it was found that asymptomatic erosive esophagitis subjects were more frequently of female gender, of older age, with a lower level of education. They also showed less alcohol and tea consumption, less depression, less anxiety, lower serum level of triglyceride, and lower prevalence of metabolic syndrome. Multivariate analysis revealed that female sex (OR = 1.645, p = 0.0146) was a positive predictive factor for asymptomatic erosive esophagitis, whereas higher level of education (OR = 0.564, p = 0.044), higher Taiwanese Depression Questionnaire score (OR = 0.922, p < 0.001), and the presence of metabolic syndrome (OR = 0.625, p = 0.0379) were negative predictive factors. CONCLUSIONS: Asymptomatic erosive esophagitis is a common feature in otherwise healthy subjects and is independently associated with female gender, lower education level, less depression, and lower prevalence of metabolic syndrome.


Asunto(s)
Enfermedades Asintomáticas/epidemiología , Depresión/epidemiología , Esofagitis/epidemiología , Reflujo Gastroesofágico/epidemiología , Síndrome Metabólico/epidemiología , Adulto , Factores de Edad , Consumo de Bebidas Alcohólicas/epidemiología , Ansiedad/epidemiología , Escolaridad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Prevalencia , Factores de Riesgo , Factores Sexuales , Taiwán/epidemiología , , Triglicéridos/sangre
15.
AIDS Care ; 26 Suppl 1: S107-12, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24735180

RESUMEN

Methadone maintenance treatment (MMT) is a key risk reduction measure for controlling HIV transmission among drug users. Studies using traditional methods exist to distinguish between drop outs and nondrop outs. However, many nondrop outs use MMT discontinuously and no study has identified situation-specific factors predicting their showing or not showing up. This study used a case-crossover design comparing situation-specific factors appearing on the last episode of attendance versus those of the last episode of nonattendance. A total of 133 participants were recruited from two MMT clinics in Guangzhou, China. Participants were asked separately whether various situation-specific factors existed in the last episodes of nonattendance and attendance of MMT. Matched odds ratios (ORs) based on conditional logistic regression analysis were presented. The results showed that the participants attended the MMT clinics on average for 25 days in the last month. Situation-specific factors significantly predicting nonattendance included: (1) physical and mental health status: in illness (OR = 33.0, P < 0.001), in a bad mood (OR = 7.5, P < 0.001), and occurrence of an unhappy event (OR = 18.0, P < 0.001); (2) other engagement: work engagement (OR = 40.0, P < 0.001), trip to other places (OR = 83.0, P < 0.001), and social activities (OR = 10.0, P = 0.012); (3) interpersonal relationship: conflicts with family (OR = 19.0, P = 0.004); and (4) structural situational factors: financial difficulty (OR = 19.0, P = 0.004) and worrying about police arrest (OR = 12.0, P = 0.003). Other factors such as interaction with drug users and heroin use were marginally significant, while reduced methadone dosage was nonsignificant. Interventions to improve MMT adherence need to consider situation-specific factors. Ancillary psychosocial services should be integrated with current MMT; MMT should also provide more flexible services to the clients. Furthermore, efforts should be taken to build up interdisciplinary teams and to connect with MMT in order to provide holistic harm reduction, rehabilitation, and health care.


Asunto(s)
Consumidores de Drogas/psicología , Metadona/administración & dosificación , Cooperación del Paciente , Adulto , Anciano , China/epidemiología , Estudios Cruzados , Femenino , Infecciones por VIH/prevención & control , Accesibilidad a los Servicios de Salud , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Tratamiento de Sustitución de Opiáceos , Valor Predictivo de las Pruebas , Factores Socioeconómicos , Centros de Tratamiento de Abuso de Sustancias
16.
ChemSusChem ; 7(2): 457-65, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24488678

RESUMEN

Four new molecules with a donor-acceptor-acceptor (D-A-A) configuration, in which 2,1,3-benzoxadiazole or 2,1,3-benzoselenodiazole were adopted as the central bridging acceptor, were synthesized as electron donors for small-molecule organic solar cells. In conjunction with two previously reported 2,1,3-benzothiadiazole-based compounds, the influences of the benzochalcogenodiazole acceptor unit and the ditolylarylamine donor moiety on the molecular structure, electrochemical behavior, and optical properties of the materials were investigated systematically to obtain a clear structure-property relationship. Vacuum-deposited hybrid planar mixed-heterojunction devices fabricated with the new donors and C70 as the acceptor showed power conversion efficiencies in the range of 2.9-4.3 % under 1 sun (100 mW cm(-2) ) AM 1.5 G simulated solar illumination. The current density-voltage characteristics of solar cells at various light intensities were measured, which revealed a high bimolecular recombination.


Asunto(s)
Suministros de Energía Eléctrica , Oxadiazoles/química , Selenio/química , Luz Solar , Modelos Moleculares , Conformación Molecular , Nitrilos/química
17.
J Sex Med ; 10(3): 642-52, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23458215

RESUMEN

INTRODUCTION: Previous studies suggest the risk of human immunodeficiency virus (HIV) transmission among men who have sex with men (MSM) is associated with characteristics of venues. However, very few studies have systematically compared HIV/sexually transmitted disease (STD) prevalence among MSM according to key venue type for sourcing sex partners. AIMS: The aim of this study was to investigate the associations between HIV/syphilis prevalence and the types of venues, namely saunas, parks, gay bars, and the Internet, which are mostly used for sourcing male sex partners by MSM in China. METHODS: Meta-analyses using fixed-effect and random-effect methods were conducted. Secondary data were obtained from 10 concurrent surveys conducted in 10 cities basing on a common protocol. Pairwise comparisons (e.g., "saunas" vs. "parks") were made. MAIN OUTCOMES MEASURES: Odds ratios (OR) for HIV/syphilis infection in relations to venue type for partner sourcing. RESULTS: The distribution of the most commonly used source to recruit male sex partner was 59.32% (Internet), 18.47% (gay bars), 14.18% (gay saunas), and 8.02% (parks). The median prevalence of HIV/syphilis was 10.49% and 19.38% (gay saunas), 2.12% and 16.25% (parks), 6.06% and 15.45% (Internet), and 4.41% and 11.90% (gay bars). We found significant between-group differences when comparing "sauna" against "Internet" (HIV: OR= 2.27, 95% confidence interval [CI] = 1.65-3.12; syphilis: OR = 1.61, 95% CI= 1.07-2.41), "sauna" against "bars" (HIV: OR= 1.65, 95% CI= 1.14-2.39; syphilis: OR= 1.35, 95% CI= 1.02-1.78), and "parks" against "Internet" (syphilis: OR= 1.55, 95% CI= 1.12-2.15) as the main source to recruit male sex partners. Other pairwise comparisons were not statistically significant. CONCLUSIONS: The results of this study suggest that those sourcing partners mainly from gay saunas have higher prevalence of HIV/syphilis when compared with those doing so via the Internet or gay bars. Venue based (sauna-based) interventions using socio-ecological approaches are greatly warranted in order to reduce HIV and syphilis prevalence among MSM in China.


Asunto(s)
Infecciones por VIH/transmisión , Homosexualidad Masculina , Baño de Vapor , Sífilis/transmisión , China/epidemiología , Infecciones por VIH/epidemiología , Humanos , Internet , Masculino , Oportunidad Relativa , Prevalencia , Instalaciones Públicas , Asunción de Riesgos , Encuestas y Cuestionarios , Sífilis/epidemiología
18.
Huan Jing Ke Xue ; 32(3): 729-35, 2011 Mar.
Artículo en Chino | MEDLINE | ID: mdl-21634171

RESUMEN

The laboratory-scale experiments were conducted to treat synthetic municipal wastewater at different C/N ratios, using a developed intelligent controller sequencing batch biofilm reactor (SBBR), which formed alternative aerobic-anoxic environment. The performance of nitrogen and phosphorus removal was investigated under different conditions (T = 25 degrees C +/- 1 degrees C, V(aeration) = 150 L/h, COD = 300 mg/L, TP = 5 mg/L, TN = 30 mg/L, t(operation) = 15 d; TN = 60 mg/L, t(operation) = 20 d; TN = 90 mg/L, t(operation) = 20 d). The average removal efficiency of COD reaches 85.2%, 91.1% and 97.7%, the average removal efficiency of TP achieves 94.1%, 95.9%, 96.7% ,the average removal efficiency of NH4(+) -N reaches 95.8%, 99.2%, 80.0%, and the average removal efficiency of TN are 90.7%, 81.1%, 58.3%, respectively. With the decrease of C/N ratios, the removal efficiency of N decreases significantly, while the removal efficiency of COD and TP increase slightly. In intelligent controlled SBBR, simultaneous nitrification and denitrification and shortened simultaneous nitrification and denitrification occur, meanwhile, the denitrification of the system strengthens with the increasing of C/N ratios. After the influent finished, intelligent controlled SBBR starts to operate in aerobic-anoxic environment. The efficiency of phosphorus removal is high, moreover, the theory of phosphorus removal is different from the conventional theory of release anaerobic and uptake aerobic phosphorus.


Asunto(s)
Biopelículas , Reactores Biológicos/microbiología , Nitrógeno/aislamiento & purificación , Fósforo/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Biodegradación Ambiental , Carbono/análisis , Ciudades , Nitrógeno/análisis , Nitrógeno/metabolismo , Reconocimiento de Normas Patrones Automatizadas , Fósforo/metabolismo
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