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1.
Environ Sci Technol ; 57(19): 7410-7420, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37134202

RESUMEN

Hot springs represent a major source of arsenic release into the environment. Speciation is typically reported to be dominated by arsenite, arsenate, and inorganic thiolated arsenates. Much less is known about the relevance and formation of methylated thioarsenates, a group with species of high mobility and toxicity. In hot spring samples taken from the Tengchong volcanic region in China, methylated thioarsenates contributed up to 13% to total arsenic. Enrichment cultures were obtained from the corresponding sediment samples and incubated to assess their capability to convert arsenite into methylated thioarsenates over time and in the presence of different microbial inhibitors. In contrast to observations in other environmental systems (e.g., paddy soils), there was no solid evidence, supporting that the sulfate-reducing bacteria contributed to the arsenic methylation. Methanosarcina, the sole genus of methanogens detected in the enrichment cultures, as well as Methanosarcina thermophila TM-1, a pure strain within the genus, did methylate arsenic. We propose that methylated thioarsenates in a typical sulfide-rich hot spring environment like Tengchong form via a combination of biotic arsenic methylation driven by thermophilic methanogens and arsenic thiolation with either geogenic sulfide or sulfide produced by sulfate-reducing bacteria.


Asunto(s)
Arsénico , Arsenitos , Manantiales de Aguas Termales , Manantiales de Aguas Termales/microbiología , Metilación , Sulfuros , Sulfatos
2.
Phys Chem Chem Phys ; 25(35): 23548-23554, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37650210

RESUMEN

3,4,9,10-Perylenetetracarboxylic-dianhydride (PTCDA) aggregates have unique optical properties and are model materials for studying exciton energy transfer (EET) in planar stacked molecular aggregates. In the framework of density matrix theory, a hierarchy of molecular transition operator expectation values could be constructed to derive the equations of motion of multi-exciton states. Realistic parameters for PTCDA molecules are used to study EET and the optical response of two-dimensional aggregates upon local excitation. Our simulations show that information about the dark state can be obtained with local field excitation and the inter-chain coupling results in a red-shift of the lowest excitonic energy level. Configuration effects, inter-chain detuning and multi-exciton states are discussed. The calculated lowest excitonic energy level of a 2D PTCDA aggregate is qualitatively consistent with the lowest experimental absorption peak of a PTCDA film. The obtained results are valuable for the study of aggregates in optical nanocavities and for the design of photoelectric devices.

3.
Cell Mol Biol (Noisy-le-grand) ; 67(6): 68-73, 2022 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-35818212

RESUMEN

Prostate cancer is a common clinical disease in men. It is known that prostate cancer ranks 3rd in the incidence of malignant tumors of the male genitourinary system in China, which is able to evaluate the riskiness of life expectancy of male patients. Therefore, we investigated the expression of CD133, recombinant human kallikrein 3 (Klk3), grainy head like 2 (grhl2) in prostate cancer, and correlation with tumor characteristics in the present study. A total of 167 prostate cancer patients who underwent surgical treatment in our hospital from February 2017 to April 2021 were selected. Their cancer and adjacent tissues were resected, and CD133 was detected by double staining using immunohistochemistry, Klk3 and grhl2 were detected by RT-PCR analysis, and CD133, Klk3 were analyzed by Pearson's method in different clinical stages, Gleason grade Correlation of grhl2 with tumor characteristics. The expression of CD133, KLK3, and GRHL2 in cancer tissue was increased compared with adjacent tissue (P < 0.05). The expression of CD133, KLK3, and GRHL2 increased with the aggravation of the clinical stage and Gleason grade (P < 0.05). CD133, KLK3, and GRHL2 showed a positive correlation in prostate cancer. The Pearson method found a positive correlation between CD133, KLK3, GRHL2 and clinical stage, Gleason grade, and lymph node metastasis. In general, high CD133, Klk3, and grhl2 expression was observed in prostate cancer and increased with the disease. They presented a positive correlation in prostate cancer presence, and these three gene products correlated with tumor characteristics.


Asunto(s)
Antígeno AC133 , Proteínas de Unión al ADN , Calicreínas , Antígeno Prostático Específico , Neoplasias de la Próstata , Factores de Transcripción , Antígeno AC133/genética , China , Proteínas de Unión al ADN/genética , Humanos , Inmunohistoquímica , Calicreínas/genética , Masculino , Clasificación del Tumor , Antígeno Prostático Específico/genética , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Factores de Transcripción/genética
4.
Phys Chem Chem Phys ; 24(5): 3289-3295, 2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35048933

RESUMEN

Constructed via in-plane heterojunction contacts between the semiconducting 2H phase (as the channel) and the metallic 1T' phase (as the electrode), two-dimensional (2D) transition metal dichalcogenide (TMD) field-effect transistors (FETs) have received much recent attention because they significantly reduce contact resistance. In this paper, ab initio quantum transport simulation is done to study and predict the electronic states and contact properties of the 2H-MoS2/1T'-MX2 (WS2, TaSe2, NbSe2, MoSe2, TaS2, and NbS2) in-plane heterojunctions. It is found that the interfacial states are not obvious and the fluctuation of the average electron density at the 1T'/2H phase boundary is small for all 2H-MoS2/1T'-MX2 heterojunctions. The average electrostatic potential differences (ΔV) are all negative, which is beneficial to promote the charge transfer from 1T'-MX2 to 2H-MoS2. Moreover, the p-type Schottky contact of the 2H-MoS2/1T'-MX2 heterojunctions is formed and the ΦSB,P values are 0.609 eV, 0.625 eV, 0.641 eV, 0.617 eV, 0.469 eV and 0.477 eV for 1T'-WS2, 1T'-TaSe2, 1T'-NbSe2, 1T'-MoSe2, 1T'-TaS2, and 1T'-NbS2, respectively. The results provide theoretical guidance for designing two-dimensional material devices.

5.
Phys Chem Chem Phys ; 23(45): 25769-25775, 2021 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-34755738

RESUMEN

Excitonic energy transfer among the zinc chlorin molecules is significant for the photovoltaic process because of their high sensitivities to harvesting sunlight. Zinc chlorin monomers and dimers can be synthesized experimentally, and they can form various self-assembled structures. Using the realistic parameters of zinc chlorin molecules, we assume that 20 molecules with J-, H- or J-H aggregation are arranged in a line and we investigate their dipole configuration effect on exciton dynamics. The expectation value approximation of operators is applied to derive the equations of motion of multi-exciton states. The temporal evolution of multi-exciton states is analyzed in the scheme of density matrix theory. Our simulations show that the inter-molecular coupling results in an exciton band and the wave-packet progressing excited by the resonant laser pulse exhibits attractive or repulsive behavior at the exciton level due to the dipole configuration effect. In the defined J-H coupling, the coherent wave-packet cannot overcome the configuration barrier to the no-excited part. The exciton dynamics revealed here might be helpful to better understand the energy transfer process in organic photovoltaic devices.

6.
Arch Pharm (Weinheim) ; 353(3): e1900294, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31894862

RESUMEN

A series of (3-benzyl-5-hydroxyphenyl)carbamates were evaluated as new antibacterial agents. Several compounds showed potent inhibitory activity against sensitive and drug-resistant Gram-positive bacteria. The compounds are ineffective against all tested Gram-negative bacteria. The structure of the ester group exerted a profound effect on antibacterial activity. 4,4-Dimethylcyclohexanyl carbamate 6h exhibited the most potent inhibitory activity against the standard and clinically isolated Staphylococcus aureus, Staphylococcus epidermidis, and Enterococcus faecalis (minimum inhibitory concentration = 4-8 µg/ml) strains. The preliminary experimental evidence indicated that these carbamates target the bacterial cell wall and share a similar mechanism of action with vancomycin.


Asunto(s)
Antibacterianos/farmacología , Carbamatos/farmacología , Enterococcus faecalis/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Staphylococcus epidermidis/efectos de los fármacos , Antibacterianos/síntesis química , Antibacterianos/química , Carbamatos/síntesis química , Carbamatos/química , Ensayos de Selección de Medicamentos Antitumorales , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Relación Estructura-Actividad
7.
Clin Infect Dis ; 67(suppl_2): S179-S188, 2018 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-30423046

RESUMEN

Background: The global dissemination of carbapenem-resistant Acinetobacter baumannii clonal complex (CC) 92 has become an urgent public health concern. Methods: A. baumannii isolates were collected in 5 tertiary hospitals in south China during 2012-2015, and their clinical data were obtained. The clinical characterization was studied by statistical analysis. Whole-genome sequencing and a Galleria mellonella infection model were used to investigate the genetic characterization and pathogenicity of isolates, respectively. Results: Sequence type (ST)457, following ST195, become the second-most prevalent clone in our collection. Patients infected by ST457 had significantly higher 7-day mortality rates (44.4% vs 14.3%; P = .01) and proportions of 7-day deaths (70.6% vs 26.7%; P = .01) than those infected by the other STs of CC92, except for ST195 and ST208. Consistently, the day of death after culture was significantly sooner in patients infected with ST457 than those with the non-ST195/208 members of CC92 (8.71 ± 15.27 vs 25.20 ± 6.51; P = .02). This is accordant with results that ST457 had enhanced virulence with a high mortality rate through use of the G. mellonella larvae infection model. Genomic analysis suggests that ST457 evolved distinctly from the other CC92 members mainly via recombinations. This clone exclusively shared a few virulence factors with the hypervirulence strain LAC-4, including a capsule biosynthesis locus (KL49) that is supposed to be important for the hypervirulence in LAC-4. Conclusions: The rising trends in prevalence and enhanced virulence of ST457 highlight the urgent need for tailored surveillance to control the further dissemination of this clone.


Asunto(s)
Infecciones por Acinetobacter/mortalidad , Acinetobacter baumannii/genética , Acinetobacter baumannii/patogenicidad , Enfermedades Endémicas , Factores de Virulencia/genética , Infecciones por Acinetobacter/microbiología , Anciano , Anciano de 80 o más Años , Animales , Técnicas de Tipificación Bacteriana , Carbapenémicos/farmacología , China/epidemiología , Evolución Molecular , Femenino , Genómica , Neumonía Asociada a la Atención Médica/epidemiología , Neumonía Asociada a la Atención Médica/microbiología , Humanos , Larva , Masculino , Persona de Mediana Edad , Mariposas Nocturnas , Tipificación de Secuencias Multilocus , Prevalencia , Virulencia , Secuenciación Completa del Genoma
8.
Phys Chem Chem Phys ; 19(36): 24971-24978, 2017 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-28875193

RESUMEN

In π-conjugated polymers for photovoltaic applications, intrinsic conjugation defects are known to play crucial roles in impacting exciton transport after photoexcitation. However, the understanding of the associated microscopic processes still remains limited. Here, we present a theoretical investigation of the effects of different conjugation defects on the dynamics of exciton transport in two linearly coupled poly(p-phenylene vinylene) (PPV) molecules. The model system is constructed by employing an extended version of the Su-Schrieffer-Heeger model and the exciton behaviors are simulated by means of a quantum nonadiabatic dynamics. We identify two types of conjugation defects, i.e., weakening conjugation and strengthening conjugation, which are demonstrated to play different roles in impacting the dynamics of exciton transport in the system. The weakening conjugation acts as an energy well inclined to trap a moving exciton, while the strengthening conjugation acts as an energy barrier inclined to block the exciton. We also systematically simulate both intrachain and interchain dynamics of exciton transport, and find that an exciton could experience a "short-time delaying", "trapping", "blocking", or "hopping" process, which is determined by the defect type, strength, and position. These findings provide a microscopic understanding of how the exciton transport dynamics can be impacted by conjugation defects in an actual polymer system.

9.
J Phys Chem Lett ; 15(9): 2550-2556, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38416028

RESUMEN

Chiral plasmonic nanostructures can produce strong chiral optical responses and have potential applications in photonics. Experimentally, metallic nanoparticle helices have been synthesized to achieve strong chiral responses. Strong coupling effects between the quantum emitters and the plasmon have attracted significant attention in the past decade and have been recently extended to the chiral plasmon of nanostructures. However, the strong coupling between molecules and metallic nanosphere helices has not been reported yet. In this article we study theoretically such an effect and examine the modulation of chiral and coupling effects by illumination light and molecular layer thickness. Our study may guide further experimental studies.

10.
Front Microbiol ; 14: 1295363, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38287960

RESUMEN

Background: The burden of cryptococcosis in mainland China is enormous. However, the in vitro characterization and molecular epidemiology in Guangdong, a key region with a high incidence of fungal infection in China, are not clear. Methods: From January 1, 2010, to March 31, 2019, clinical strains of Cryptococcus were collected from six medical centres in Guangdong. The clinical information and characteristics of the strains were analysed. Furthermore, molecular types were determined. Results: A total of 84 strains were collected, mostly from male and young or middle-aged adult patients. Pulmonary and cerebral infections (82.1%) were most common. All strains were Cryptococcus neoformans, grew well at 37°C and had capsules around their cells. One melanin- and urea- and one melanin+ and urea- variants were found. Although most strains exhibited a low minimum inhibitory concentration (MIC) value for voriconazole (mean: 0.04 µg/mL) and posaconazole (mean: 0.12 µg/mL), the results for these isolates showed a high degree of variation in the MIC values of fluconazole and 5-fluorocytosine, and resistance was observed for 4 out of 6 drugs. A significant proportion of these strains had MIC values near the ECV values, particularly in the case of amphotericin B. The proportion of strains near the clinical breakpoints was as follows: fluconazole: 3.66%; voriconazole: 3.66%; itraconazole: 6.10%; posaconazole: 13.41%; amphotericin B: 84.15%; 5-fluorocytosine: 2.44%. These strains were highly homogeneous and were dominated by the Grubii variant (95.2%), VNI (94.0%), α mating (100%), and ST5 (89.3%) genotypes. Other rare types, including ST4, 31, 278, 7, 57 and 106, were also found. Conclusion: Phenotypically variant and non-wild-type strains were found in Guangdong, and a significant proportion of these strains had MIC values near the ECV values towards the 6 antifungal drugs, and resistance was observed for 4 out of 6 drugs. The molecular type was highly homogeneous but compositionally diverse, with rare types found. Enhanced surveillance of the aetiology and evolution and continuous monitoring of antifungal susceptibility are needed to provide references for decision-making in the health sector and optimization of disease prevention and control.

11.
Am J Otolaryngol ; 33(5): 523-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22306788

RESUMEN

OBJECTIVES: An acute interruption of the blood supply to the inner ear is one of the most likely causative factors for sudden deafness (SD). Reactive oxygen species (ROS) have been suggested to be important mediators of the tissue injury during cochlear ischemia and reperfusion. Radix astragali (RA) is natural antioxidant. The aim of this study was to investigate the efficacy of RA in patients with SD. PATIENTS AND METHODS: We compared the hearing gains from hearing impairment in 46 ears treated with RA with 46 ears treated with non-RA. RA was given intravenously daily for 10 days. There were no significant differences in clinical or audiological data between RA and non-RA groups. RESULTS: The hearing gain at 250, 500, 1000, 2000, and 4000 Hz in RA group was much higher than that of non-RA group correspondingly (P < .01). Also, the hearing gain at PTA (pure-tone average of 250, 500, 1000, 2000, and 4000 Hz) in RA group was significantly higher than that of non-RA group (P < .01). CONCLUSION: The recovery of hearing was significantly better after treatment of RA than non-treatment of RA. RA can be valuable concurrent therapy for patients with SD.


Asunto(s)
Medicamentos Herbarios Chinos/administración & dosificación , Pérdida Auditiva Súbita/tratamiento farmacológico , Audición/fisiología , Recuperación de la Función/efectos de los fármacos , Adulto , Anciano , Anciano de 80 o más Años , Planta del Astrágalo , Astragalus propinquus , Audiometría de Tonos Puros , Femenino , Estudios de Seguimiento , Pérdida Auditiva Súbita/fisiopatología , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
12.
Sci Total Environ ; 827: 154016, 2022 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-35271921

RESUMEN

Arsenic (As) from deep crust is transported by geothermal waters to the earth surface and retained by sediment through adsorption, which depends significantly on the occurring As species. Adsorption of oxyarsenic species (i.e. arsenite [iAs(III)] and arsenate [iAs(V)]) on pure minerals was intensively investigated, yet studies with natural sediments and less known As species are scarce. To fill this gap, we investigated adsorption kinetics of nine different As species onto three typical geothermal sediments with different sedimentary organic matter (SOM) and iron (Fe) levels under anaerobic, sulfidic conditions (pH = 6). A multispecies pseudo-second-order (MPSO) model was applied to extract the adsorption rates of individual As species. Results showed that only the sediment with both high SOM and high Fe exhibited considerable As adsorption capacity. Air exposure or rise of either SOM or Fe levels in sediment favoured de-thiolation of aqueous thioarsenates, except for dimethylated thioarsenates. The overall adsorbed amount of the spiked As was affected by concurrent (de-)thiolation of the initial species, and the rates of their adsorption to the high SOM and high Fe sediment decreased in the order of tetrathioarsenate (TetraTA) > monothioarsenate (MTA) > iAs(V) > monomethyl arsenate (MMA) > dimethyl arsenate (DMA) > iAs(III) > monomethyl monothioarsenate (MMMTA) > dimethyl monothioarsenate (DMMTA) > dimethyl dithioarsenate (DMDTA). The fastest and slowest adsorption were suggested for inorganic thioarsenates and methylated thioarsenates, respectively. Therefore, under typical geothermal scenarios, thiolation of inorganic As would not necessarily increase its mobility, but the formation of methylated oxyarsenates and their further thiolation would endow geothermal As with strong migration ability.


Asunto(s)
Arsénico , Arsenicales , Arseniatos , Metilación , Sulfuros
13.
Medicine (Baltimore) ; 101(46): e31911, 2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36401434

RESUMEN

Adjuvant endocrine therapy (AET) is known to reduce the risk of hormone receptor-positive (HR+) breast cancer (BC) recurrence and mortality rates, but its impact on cardiovascular disease (CVD) events is unclear. The primary objective of this study was to analyze the association of HR status with CVD mortality in patients with stage I to III BC. A retrospective study of patients with stage I to III BC was conducted using the 2004 to 2016 Surveillance, Epidemiology, and End Results (SEER) database, and patients were grouped according to their HR status. Propensity score matching (PSM) was used to adjust for heterogeneity between the groups. The cumulative incidence rate of CVD mortality was evaluated via a cumulative incidence curve. Univariate and multivariate Fine and Gray's competing risk regression models were used to identify risk factors associated with CVD mortality. In total, 399,209 patients with BC were included in this study, and 329,958 patients (82.65%) were HR-positive. The cumulative incidence of CVD death was 8.28% in stage I to III BC patients. In the constituent ratio analysis, primary BC was the leading cause of death (45.29%, N = 31,465), followed by heart disease (16.07%, N = 11,166). Compared to the second year following BC diagnosis, the risk of CVD-specific death gradually increased. After PSM, 65,952 pairs of patients were matched, which led to the equilibrium of all variables between the HR-negative cohort and HR+ cohort. Multivariate analysis indicated that HR status was not significantly associated with the risk of CVD mortality, with a hazard ratio of 1.01 (P = .895). This study highlights the importance of understanding the associations between risk factors and CVD for BC patients. HR status was not associated with the risk of CVD mortality in this study.


Asunto(s)
Neoplasias de la Mama , Enfermedades Cardiovasculares , Humanos , Femenino , Estudios Retrospectivos , Recurrencia Local de Neoplasia/complicaciones , Hormonas
14.
Front Endocrinol (Lausanne) ; 13: 1014558, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36213273

RESUMEN

Objective: This study aimed to examine the efficacy of HRT with gonadotropin-releasing hormone agonist (GnRH-a) pre-treatment in women with male-factor infertility who underwent a frozen embryo transfer (FET) programme. Design: Between January 2016 and October 2020, 2733 women with male-factor infertility who underwent the HRT protocol as the endometrial preparation method were enrolled at two Reproductive Medicine Centres. Patients were divided into two groups based on whether they had GnRH-a pre-treatment before HRTs: the GnRHa-HRT group and the HRT group. The inverse probability of treatment weighting (IPTW) method was conducted to balance patient baseline characteristics between treatment cohorts to reduce selection bias. The live birth rate was considered regarded as the primary pregnancy outcome. Results: Multivariate logistic regression adjusted for confounding factors, the GnRHa-HRT group showed a notably higher rate of live birth (OR 2.154, 95% CI 1.636~2.835, P<0.001) when compared to the HRT group. Additionally, the rate of miscarriage was significantly lower in the GnRHa-HRT group. The GnRHa-HRT group had significantly higher rates of biochemical pregnancy, clinical pregnancy, multiple pregnancy, and term birth. Conclusion: The endometrial preparation protocol of HRT with GnRH-a pre-treatment could obviously increase the live birth rate for women with male-factor infertility undergoing the FET programme.


Asunto(s)
Infertilidad , Resultado del Embarazo , Transferencia de Embrión/métodos , Femenino , Hormona Liberadora de Gonadotropina , Terapia de Reemplazo de Hormonas , Humanos , Masculino , Embarazo
15.
Phys Chem Chem Phys ; 13(19): 8755-68, 2011 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-21499637

RESUMEN

Laser pulse control of electron transfer through a single molecule attached to nano electrodes is demonstrated theoretically by concentrating on the case of weak and intermediate molecule-lead coupling. A rate equation description is used to determine the populations of the different electron-vibrational states of the molecule in its neutral or charged state. Caused by the photoinduced population of excited electronic states new transmission channels are opened which change the current through the molecular junction. The transient behavior of the current is studied if the external laser pulse excitation is switched on and off or if a pulsed excitation is applied. Pulse durations of some hundreds of fs up to 50 ps are considered. Within this computational scheme the interrelation of characteristic times of charging, discharge, vibrational relaxation, and the turn on and off of the photoexciation is demonstrated. Possible self-stabilization of an excited junction state is found. Some estimates of potential effects of plasmon excitations in the leads are also given. To have a quantity available which offers direct experimental access to the transient state of the junction the time and frequency resolved photo emission spectrum of the molecule is calculated.


Asunto(s)
Rayos Láser , Simulación por Computador , Técnicas Electroquímicas , Electrodos , Cinética , Nanotecnología
16.
Artículo en Inglés | MEDLINE | ID: mdl-34831998

RESUMEN

With the acceleration of industrialization and urbanization, the Yangtze River Economic Belt (YREB) is facing many environmental problems that need to be solved in the process of development. This paper aims to analyze the environmental governance effects of nine provinces and two municipalities in the Yangtze River Economic Belt from 2009 to 2018. Firstly, based on the input-output index, the slacks-based measure (SBM) undesirable model and Malmquist (ML) index were used to measure the green total factor productivity (GTFP) of the YREB from 2009 to 2018. The results showed that the technological progress index contributed the most to the GTFP of the YREB, followed by the pure technical efficiency index and the scale efficiency index. Environmental regulation has no significant impact on the GTFP of the YREB. Secondly, by analyzing the effect of environmental governance in the YREB, the results show that the main reasons for the ineffective environmental governance in the YREB are the redundant input of environmental resources, excessive unwanted output, and low harmless treatment rate of municipal solid waste, rather than the low level of urban environmental management. Finally, this paper provides recommendations for the ineffective provinces and municipalities of the YREB to further optimize the input-output factors of environmental governance.


Asunto(s)
Desarrollo Económico , Ríos , China , Ciudades , Conservación de los Recursos Naturales , Política Ambiental
17.
BMC Gastroenterol ; 10: 100, 2010 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-20815889

RESUMEN

BACKGROUND: Primary biliary cirrhosis (PBC) is an autoimmune liver disease characterized by the presence of anti-mitocondrial autoantibodies (AMA) which has an essential role also for diagnosis. In addition, also some anti-nuclear antibodies (ANA) have been shown to be highly specific PBC. The purpose of this study was to assess the prevalence of PBC among the adults referring hospital for annual health check-up in Southern China by screening sera for PBC-specific autoantibodies. METHODS: AMA and ANA were screened in 8,126 adults (mean age 44 ± 15 years, 48% females) by indirect immunofluorenscence (IIF). Positive sera were tested by ELISA/immunoblotting for AMA-M2, anti-sp100 and anti-gp210. A diagnosis of PBC was re-assessed six months after the initial testing. RESULTS: Out of 8,126 individuals 35 were positive for AMA and 79 positive for ANA. Nineteen, 4, and 3 of the subjects positive for AMA and/or ANA showed reactivity for AMA-M2, anti-sp100 or gp210, respectively, further tested with ELISA/immunoblotting. Fourteen in the 39 individuals positive for AMA at IIF, AMA-M2, anti-gp210, or anti-sp100 had abnormal cholestatic liver functional indices. One definite and 3 probable PBC diagnosis could be made in 4 cases including 3 females and 1 male after half a year. CONCLUSIONS: We found a point prevalence rate of PBC among Southern Chinese adults attending for yearly health check-up of 492 cases per million (95% CI, 128 to 1,093) and 1,558 cases per million (95% CI, 294 to 3,815) for women over 40, a finding similar to prevalence reported in other geographical areas.


Asunto(s)
Anticuerpos Antinucleares/análisis , Autoanticuerpos/análisis , Estado de Salud , Cirrosis Hepática Biliar/epidemiología , Tamizaje Masivo/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , China/epidemiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Humanos , Immunoblotting , Cirrosis Hepática Biliar/diagnóstico , Cirrosis Hepática Biliar/inmunología , Masculino , Persona de Mediana Edad , Mitocondrias/inmunología , Prevalencia , Adulto Joven
18.
Microb Drug Resist ; 26(2): 100-109, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31441704

RESUMEN

ZTW-41, an indolizinoquinoline-5,12-dione derivative, was investigated for antibacterial activity against Gram-positive bacteria, especially methicillin-resistant Staphylococcus aureus (MRSA). In our study, the MIC90s (minimum inhibitory concentrations) of ZTW-41 against MRSA (MRSA, n = 200), methicillin-sensitive S. aureus (MSSA, n = 100), Enterococcus faecalis (E. faecalis, n = 32), and Enterococcus faecium (E. faecium n = 32) were 0.25, 0.25, 0.125, and 8 µg/mL, respectively, whereas the MBC90s (minimum bactericidal concentrations) were 2, 1, 1, and >32 µg/mL, respectively. ZTW-41 maintained its potency at different pH levels (range 5-9) and in starting inoculum size up to 107 CFU/mL. The presence of human serum (25-75%) increased ZTW-41 MICs by two- to eightfold. Time-kill curves showed that ZTW-41 had bactericidal activity against MRSA, MSSA, and E. faecalis strains within 8 hours, and rebound growth occurred after 8 hours except at higher multiples of the MIC (4 × and 8 × ). In the acute toxicity study, no mortality or signs of toxicity was noted in mice after 14 days of observation at doses <50 mg/kg. ZTW-41 exhibited good selectivity indices (SIs) (SI = IC50/MIC90) ranging from 1.12 to 71.76 against clinical isolates, demonstrating excellent therapeutic selectivity in MRSA, MSSA, and E. faecalis strains. Moreover, the in vivo efficacy (effective dose [ED]50 = 6.59 mg/kg) of ZTW-41 was found comparable with vancomycin. Collectively, our favorable results supported ZTW-41 as a promising investigational candidate for treating drug-resistant bacteria infection.


Asunto(s)
Antibacterianos/farmacología , Enterococcus/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Farmacorresistencia Bacteriana Múltiple , Humanos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Ratones , Pruebas de Sensibilidad Microbiana , Unión Proteica
19.
Zhonghua Gan Zang Bing Za Zhi ; 16(12): 922-5, 2008 Dec.
Artículo en Zh | MEDLINE | ID: mdl-19105938

RESUMEN

OBJECTIVE: To investigate the frequencies of primary biliary cirrhosis (PBC)-specific autoantibodies, including antimitochondrial autoantibodies (AMA) M2, anti-gp210 and anti-Sp100, and to assess their point prevalence rates in a general adult population group in Guangzhou. METHODS: Eight thousand one hundred twenty-six adults (mean age 43.5+/-14.6 years, range 18 to 83 years; 4248 males and 3878 females) were enrolled for this study. AMA and anti-nuclear antibodies (ANA) were screened by indirect immunofluorescence test and AMA-M2, anti-gp210 and anti-sp100 were further detected using ELISA or immunoblotting assay. PBC diagnosis was made according to criteria recommended by AASLD in 2000. RESULTS: Of the 8126 adults tested, 35 (0.43%) and 79 (0.97%) were found to be positive for AMA and ANA. The positivity for both of AMA and ANA increased with aging. Twenty-two cases were positive for PBC-specific autoantibodies. Frequencies for AMA-M2, anti-sp100 and anti-gp210 in the general adult population were 0.23%, 0.05% and 0.04% respectively and their frequency reached 0.62% in women over 40 years. A woman among the 22 cases who was PBC-specific autoantibody positive was finally diagnosed as a PBC patient. CONCLUSION: Our data indicates that PBC specific autoantibodies exist in the general adult population at very low frequencies and the point prevalence rate of PBC in adults in Guangzhou is not less than that of other areas.


Asunto(s)
Especificidad de Anticuerpos , Autoanticuerpos/sangre , Cirrosis Hepática Biliar/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Adulto Joven
20.
Sci Rep ; 7(1): 15279, 2017 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-29127419

RESUMEN

Acinetobacter baumannii has been a dreadful problem for ICU physicians for a long time. Bacteremic pneumonia (BP) caused by this organism has a higher mortality compared to other organisms. Between 2012 and 2015, 86 BP and 89 non-bacteremic pneumonia (NBP) patients from five ICUs were enrolled into the study. The 7-day and 14-day mortality rates were higher in BP patients than in NBP patients (P < 0.001). Procalcitonin elevation, high APACHEII score and recent surgery, were independently associated with BP episodes. Acute respiratory distress syndrome, coma, high APACHEII score and procalcitonin elevation, were independently associated with mortality in the BP group. Extensively drug-resistant isolates were detected in 34.9% of BP and 25.8% of NBP isolates. PFGE identified 12 and 9 genotypes in the BP and NBP isolates, respectively, with 6 genotypes shared by both groups. ST195 was the most prevalent type (40%), followed by ST457 (18.9%). The pandemic clonal complex 92 was predominant, accounting for 94.3% of the strains. For all studied periods, mortality remained higher in the BP than the NBP group. Disease severity was the main risk factor for high mortality in the BP group, and other factors related to mortality were infection, and not treatment or microbiology-related.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Bacteriemia , Farmacorresistencia Bacteriana , Unidades de Cuidados Intensivos , Neumonía Bacteriana , Síndrome de Dificultad Respiratoria , Infecciones por Acinetobacter/tratamiento farmacológico , Infecciones por Acinetobacter/microbiología , Infecciones por Acinetobacter/mortalidad , Anciano , Anciano de 80 o más Años , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Bacteriemia/mortalidad , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neumonía Bacteriana/tratamiento farmacológico , Neumonía Bacteriana/microbiología , Neumonía Bacteriana/mortalidad , Prevalencia , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Síndrome de Dificultad Respiratoria/microbiología , Síndrome de Dificultad Respiratoria/mortalidad
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