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1.
Small ; 13(29)2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28594457

RESUMEN

Nitrogen-doped and nitrogen and oxygen codoped carbon nanobelts (CNBs) (denoted as N-CNBs and N-O-CNBs, respectively) are respectively obtained by pyrolyzing the self-aligned polypyrrole (PPy) NBs and Se@poly(2-methoxy-5-nitroaniline) core@shell nanowires. Particularly, the uniform size, unique nanostructure, and well-defined edges of the PPy NBs result in the uniform size of the doped CNBs with an extraordinarily high N doping level (≈16 at%), especially the very large concentrations of the redox active pyridinic (9 at%) and pyrrolic N (3.5 at%) species. Furthermore, the precursors in highly self-aligned, dense arrays give rise to a very high packing density for the N-CNBs and N-O-CNBs. These incomparable features provide not only appropriate pathways for the introduction of pseudocapacitance via rapid Faradaic reactions and enhancement of volumetric capacitance but also structural design and synthesis approach to new types of nanostructured carbon. Notably, the N-CNBs obtained at the pyrolysis temperature of 800 °C (N-CNB8) in symmetric electrochemical cells deliver a specific capacitance of 458 F g-1 and ultrahigh volumetric capacitance of 645 F cm-3 in aqueous solution, which are among the best performance ever reported for carbon-based supercapacitive materials.

2.
Mol Vis ; 23: 407-415, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28744092

RESUMEN

PURPOSE: This study aimed to establish a method for testing Staphylococcus aureus in the vitreous of endophthalmitis with matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS), which is simple, fast, and sensitive. METHODS: S. aureus at different numbers was either mixed with homogenized vitreous or inoculated in porcine eyes for culturing, followed by homogenization. The homogenized vitreous samples, with or without centrifugation, were stained with Gram and Coomassie Blue (CBB) dyes and cultured with blood agar. The pellet of the vitreous mixture was analyzed with MALDI-TOF-MS. RESULTS: The minimum detectable levels of S. aureus in H2O and in the pellet of homogenized vitreous were 9.0 × 103 (positive rate, 22.2%) and 1.0 × 104 CFU/µl (positive rate, 11.1%), respectively. In the vitreous samples inoculated with S. aureus and cultured for 12 h, the number of S. aureus increased in a dose-dependent manner to the number of bacteria in the inoculate. In the supernatant of the homogenized vitreous, there were traces of bacteria identified with Gram staining. On the blood agar plates, the supernatant grew a few colonies, while the pellet grew intensive colonies. The vitreous fragments that were stained with CBB were displayed in the supernatants, in small numbers, and in the pellets. When the inoculated number was 1.0 × 104 CFU/µl or higher, the bacteria in the vitreous pellets could be identified in all samples (100%, n = 9). However, bacteria could be detected in only two out of nine spots of pellets (22.2%) if the number of inoculated S. aureus was 1.0 × 103 CFU/µl. CONCLUSIONS: A method for testing S. aureus directly from vitreous samples of endophthalmitis by the combination of easy extraction methods and a MALDI-TOF- MS assay was provided. This rapid identification method is easily adaptable for use in clinical routine and can help reduce the delay in diagnosis, allowing for earlier therapeutic intervention in patients.


Asunto(s)
Endoftalmitis/diagnóstico , Infecciones Bacterianas del Ojo/diagnóstico , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Infecciones Estafilocócicas/diagnóstico , Staphylococcus aureus/aislamiento & purificación , Cuerpo Vítreo/microbiología , Animales , Técnicas Bacteriológicas , Sangre/microbiología , Recuento de Colonia Microbiana , Modelos Animales de Enfermedad , Endoftalmitis/microbiología , Infecciones Bacterianas del Ojo/microbiología , Violeta de Genciana , Humanos , Fenazinas , Infecciones Estafilocócicas/microbiología , Porcinos
3.
Phys Chem Chem Phys ; 17(47): 31956-65, 2015 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-26567941

RESUMEN

Branched Pd nanocrystals (NCs) with tunable architectures are synthesized in high yields (>95%) by simply adjusting the concentration of H2PdCl4 in the presence of fixed amounts of cetyltrimethylammonium bromide (CTAB), L-ascorbic acid (L-AA), and CuBr2(-) that is produced by reducing CuBr2 with L-AA. The as-synthesized branched Pd NCs have long, straight branches with thin diameters. At the same time, the growth process of the branched Pd NCs is monitored, which provides mechanistic insights for the branching growth of Pd NCs. It is identified that a high concentration of CTAB combined with an appropriate amount of CuBr2(-) species, acting as an in situ cooperatively organized template, is a decisive factor for the anisotropic growth of the branched Pd nanostructures during aqueous-phase reduction of the Pd precursor, using L-AA as a reducing agent. The electrocatalytic activities of the branched Pd NCs were tested. The branched Pd NCs are found to be an excellent electrocatalyst for the methanol oxidation reaction (MOR) largely due to the size and morphological effects of the branched structures.

4.
Phys Chem Chem Phys ; 17(4): 2794-803, 2015 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-25501713

RESUMEN

A simple solution-phase route was developed for the large-scale synthesis of self-organized, closely packed ultralong single crystalline Se nanowire superstructures with diverse morphologies and macroscopic dimensions even extending over several millimeters. The hierarchical architectures of self-organized Se nanowires were formed by reducing H2SeO4 with a bisubstituted aniline, such as 3,5-dimethoxyaniline, 2,5-dimethoxyaniline, 2,6-dimethoxyaniline, and 2-methoxy-5-nitroaniline under solvothermal conditions. Scanning electron microscopy studies show 100% morphological yield and morphological uniformity of the self-organized hierarchical architectures. Based on the dependence of the Se nanostructures on the synthetic conditions, especially the molecular structures of reductants and solvent, we proposed a plausible mechanism to account for the formation of the distinctive morphologies of the self-organized nanowire architectures. The field emission characteristics of the Se nanowires synthesized using 2,6-dimethoxyaniline and 2-methoxy-5-nitroaniline as the reductants are studied. These well-aligned Se nanowires show very low turn-on field (Eto) and threshold field (Ethr) as well as high emission current densities under low applied electric fields, which are superior to most of the one-dimensional (1D) nanostructures reported previously, due to their exceptional aspect ratios (>20 000) and sharp tips in combination with the nature of low band gap and high conductivity of Se. Furthermore, the Se nanowire emitters exhibit good emission current stability with small fluctuations (typically, less than 3%) over a period of 1000 min.

5.
Chem Commun (Camb) ; 60(20): 2756-2759, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38353110

RESUMEN

In this work, the formed interfacial Co-O-Cu bonds in Co-doped Cu(OH)2 (Co2-Cu(OH)2) sufficiently expose active sites and improve the reaction kinetics. As a result, the optimal Co2-Cu(OH)2 provides an amazing faradaic efficiency (91.6%), high selectivity (93.2%) and robust stability toward the NO3RR.

6.
Oncol Lett ; 26(6): 509, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37920429

RESUMEN

Small gastrointestinal stromal tumors (GISTs) are rare and malignant tumors that originate in the mesenchymal tissue. Due to their insidious onset and nonspecific symptoms, they are often misdiagnosed, and are generally detected during the diagnosis and treatment of other diseases. The present case report reviewed the treatment process of a patient with a small GIST coexisting with pancreatic cancer who was admitted to the Yiwu Central Hospital (Yiwu, China) in June 2018. The patient was diagnosed and treated comprehensively using a combined approach of urology, and gastrointestinal and hepatobiliary surgery. The present case report provides important clinical insights, which allow for an improved understanding of GIST and provides a reference for clinical treatment.

7.
Eur J Med Chem ; 246: 114970, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36470106

RESUMEN

Bromodomain protein 4 (BRD4) is an attractive epigenetic target that regulating diverse cellular processes, and the discovery of dual-target inhibitors including BRD4 is an effective approach in cancer treatment to increase potency and reduce drug resistance. Based on the multifunctional drug development strategy, a series of new derivatives of nitrooxy (ONO2) or furoxan (1,2,5-oxadiazole 2-oxide) with BRD4 inhibitor capable of inhibiting BRD4 and simultaneously releasing NO were designed and synthesized. When NO concentrations were measured with Griess reagent under physiological conditions, all compounds released NO at micromolar levels, reaching effective antitumor concentrations. Biological studies showed that the most potent BRD4/NO hybrid 11a exhibited good BRD4 inhibitory activity and selectivity. Further mechanistic studies revealed that 11a significantly decreased the expression of BRD4 and c-Myc, as well as induced cellular apoptosis and autophagic cell death both in vitro and in vivo. In summary, we optimized the chimeric BRD4-inhibitor/NO-donor based on our previous studies, and it should be a lead compound for targeted therapy of OC (ovarian cancer) in the future. This interesting strategy could expand the usage of BRDi in human malignancies and endogenous gastro-transmitters.


Asunto(s)
Antineoplásicos , Neoplasias , Humanos , Relación Estructura-Actividad , Proteínas Nucleares , Óxido Nítrico/farmacología , Proteínas de Ciclo Celular , Ensayos de Selección de Medicamentos Antitumorales , Diseño de Fármacos , Proliferación Celular , Factores de Transcripción/metabolismo , Línea Celular Tumoral , Pirimidinas/farmacología
8.
Am J Transl Res ; 14(4): 2567-2579, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35559369

RESUMEN

BACKGROUND: The dysregulation of long non-coding RNAs (lncRNAs) has been implicated roles in the pathogenesis of many human diseases, including hepatic diseases. Several lncRNAs have been associated with the progression of hepatocellular carcinoma (HCC), but their function as diagnostic markers for liver cancer remain to be determined. OBJECTIVE: This study aimed to identify the potential diagnostic markers for liver cancer. METHODS: The Cancer Genome Atlas (TCGA) database was used to obtain the gene transcriptome data of liver cancer. In addition, this study enrolled 70 liver cancer patients admitted to the Yiwu Central Hospital and 50 healthy people who concurrently underwent physical examinations from February 2017 to January 2020. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to detect the expression of C10orf91 and LINC01224 in the patients' tissues and serum. A 5-year follow-up was conducted for survival observation. The potential and targeted miRs of C10orf91 and LINC01224 were predicted by online database for miRNA target prediction. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted and competing endogenous RNA (ceRNA) network was plotted. RESULTS: A total of 175 differentially expressed lncRNAs were screened out, of which 173 were upregulated and 2 were downregulated. C10orf91, and LINC01224 were independent prognostic factors for liver cancer (P<0.05). C10orf91 and LINC01224 had diagnostic value for differentiating liver cancer, tumor node metastasis (TNM) staging, and lymphatic metastasis. GO and KEGG enrichment analysis showed that C10orf91 and LINC01224 were involved in 23 significant biological functions and 35 significant signal transduction pathways respectively. CONCLUSION: C10orf91 and LINC01224 are highly expressed in liver cancer patients withpoor prognosis.

9.
Infect Drug Resist ; 15: 3267-3276, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35769550

RESUMEN

Purpose: This study aims to assess the testing methods used to detect fungal pathogens as well as the pathogenic profiles and drug susceptibility among fungal isolates from ocular sources collected in a tertiary eye hospital. Methods: The laboratory test records of patients with suspected ocular fungal infection from January 2010 to December 2019 at a tertiary eye care center in southern China were retrospectively evaluated. The isolated pathogens identified by smear examination and culture combined with microscopy were analyzed. For 2017-2019 fungal isolates, their antifungal susceptibilities to four antifungal agents were evaluated. Results: A total of 22,233 specimens (16,315 for culture and 5918 for direct smear examination) from 16,209 individuals were assessed, and 3317 specimens (2169 for culture and 1148 for smear examination) from 2395 patients had confirmed fungal infection. The mean age of patients was 50.6±14.2 years and 63.4% were male. The positive rate of smear examination was 19.4% and significantly higher than 13.3% of fungal culture (p< 0.001). Of 5812 patients who were simultaneously examined for culture and smear staining, 897 (15.43%) had positive findings for fungi. Among the 2420 positive findings, 2138 (88.3%) were from the cornea, and 133 (5.5%) were from intraocular samples. Fusarium spp. (40.5%) and Aspergillus spp. (22.0%) were the major fungal genera among the molds, whereas Candida spp. (4.6%) constituted the major yeast. Fusarium spp. had a lower antifungal susceptibility than Aspergillus spp. against voriconazole and amphotericin. And yeast spp. had the highest susceptibility to caspofungin. Conclusion: This study provided a 10-year assessment of fungi in ocular infections in southern China, giving support to epidemiological understanding and guiding empiric antimicrobial therapy.

10.
Front Microbiol ; 13: 992582, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36386677

RESUMEN

Background: Fusarium species are opportunistic causative agents of superficial and disseminated human infections. Fast and accurate identification and targeted antifungal therapy give help to improve the patients' prognosis. Objectives: This study aimed to evaluate the effectiveness of matrix-assisted laser desorption ionisation time of flight mass spectrometry (MALDI-TOF MS) for Fusarium identification, and investigate the epidemiology and antifungal susceptibility profiles of clinical Fusarium isolates in Southern China. Methods: There were 95 clinical Fusarium isolates identified by DNA sequencing of translation elongation factor 1-alpha (TEF1α) and MALDI-TOF MS, respectively. Antifungal susceptibility testing of isolates was performed by broth microdilution according to the CLSI approved standard M38-A3 document. Results: Seven species complexes (SC) with 17 Fusarium species were identified. The most prevalent SC was the F. solani SC (70.5%, 67/95), followed by the F. fujikuroi SC (16.8%, 16/95). F. keratoplasticum within the F. solani SC was the most prevalent species (32.6%, 31/95). There were 91.6% (87/95) of isolates identified by MALDI-TOF MS at the SC level. In most of species, amphotericin B and voriconazole showed lower MICs compared to itraconazole and terbinafine. The F. solani SC showed higher MICs to these antifungal agents compared to the other SCs. There were 10.5% (10/95) of strains with high MICs for amphotericin B (≥8 µg/ml), terbinafine (≥32 µg/ml) and itraconazole (≥32 µg/ml) simultaneously, mostly focusing on F. keratoplasticum (9/10). Conclusion: MALDI-TOF MS exhibited good performance on the identification of Fusarium strains at the SC level. The F. solani SC was the most prevalent clinical SC in Southern China. The MICs varied significantly among different species or SCs to different antifungal agents.

11.
Food Funct ; 12(19): 9380-9390, 2021 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-34606537

RESUMEN

Sucralose is one of the most widely used artificial sweeteners, free of nutrients and calories. Its approval and uses correlate with many of the worldwide epidemiological changes in inflammatory bowel disease (IBD). Multiple animal studies by us and others showed that sucralose exacerbated ileitis in SAMP1/YitFc mice and 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats. In this study, we further investigated the effect of sucralose on dextran sulfate sodium (DSS)-induced colitis in mice and the associated mechanisms. Male C57BL/6 mice received 1.5 mg ml-1 sucralose in drinking water for 6 weeks. Then, 2.5% DSS was added to drinking water for 7 days to induce ulcerative colitis (UC). The results showed that, compared with the DSS group, administration of sucralose exacerbated the severity of colitis as indicated by the further decrease in body weight, increase in disease activity index (DAI) and the expression of pro-inflammatory cytokines, as well as the activation of the TLR5-MyD88-NF-κB signaling pathway, and the disturbances of intestinal barrier function, along with changes in the intestinal microbiota. Our findings indicate that sucralose may increase the susceptibility to DSS-induced colitis through causing dysbiosis of intestinal microbiota and damage to the intestinal barrier.


Asunto(s)
Colitis Ulcerosa/etiología , Colitis Ulcerosa/microbiología , Microbioma Gastrointestinal , Sacarosa/análogos & derivados , Edulcorantes/efectos adversos , Animales , Colitis Ulcerosa/inmunología , Colitis Ulcerosa/patología , Citocinas/metabolismo , Sulfato de Dextran , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Disbiosis/etiología , Mucosa Intestinal/patología , Mucosa Intestinal/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Factor 88 de Diferenciación Mieloide/metabolismo , FN-kappa B/metabolismo , Índice de Severidad de la Enfermedad , Transducción de Señal , Sacarosa/efectos adversos , Receptor Toll-Like 5/metabolismo
12.
Commun Chem ; 3(1): 154, 2020 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-36703390

RESUMEN

The oxygen evolution reaction is an essential factor in many renewable energy technologies, such as water splitting, fuel cells, and metal-air batteries. Here we show a unique solution to improve the oxygen evolution reaction rate by adjusting the electrolyte composition via the introduction of hexadecyltrimethylammonium hydroxide into an alkaline electrolyte. The strong adsorption of hexadecyltrimethylammonium cations on the surface of electrocatalysts provides the increased absolute number of OH- ions near the electrocatalyst surface, which effectively promotes the oxygen evolution reaction performance of electrocatalysts, such as Fe1-yNiyS2@Fe1-xNixOOH microplatelets and SrBaNi2Fe12O22 powders. Meanwhile, we present an electrochemical conditioning approach to engineering the electrochemically active surface area of electrocatalysts, by which the resultant Fe1-yNiyS2@Fe1-xNixOOH microplatelets have a larger electrochemically active surface area after the electrochemical conditioning of the as-synthesized Fe1-yNiyS2 microplatelets using ammonia borane than those obtained after the conventional electrochemical conditioning without ammonia borane, presumably due to the appropriate conversion rate of Fe1-xNixOOH shells.

13.
Front Oncol ; 10: 710, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32582527

RESUMEN

Sucralose is a calorie-free high-intensity artificial sweetener that is widely used in thousands of foods and beverages all over the world. Although it was initially regarded as a safe, inert food additive, its adverse effect on gut microbiota and health has drawn more and more attention as evidence accumulates. Studies by us and others revealed that sucralose exacerbated gut damage and inflammation in animal models for inflammatory bowel disease (IBD), including those for both ulcerative colitis, and Crohn's disease. Our study demonstrated that sucralose greatly aggravated dextran sulfate sodium (DSS)-induced colitis along with causing changes in gut microbiota, the gut barrier and impaired inactivation of digestive proteases mediated by deconjugated bilirubin. It is well-documented that IBD greatly increases the risk of colorectal cancer (CRC), the globally third-most-common cancer, which, like IBD, has a high rate in the developed countries. Azoxymethane (AOM)/DSS has been the most commonly used animal model for CRC. In this study, we further explored the effect of sucralose on tumorigenesis and the possible mechanism involved using the AOM/DSS mouse model. First, 1.5 mg/ml sucralose was included in the drinking water for 6 weeks to reach a relatively stable phase of impact on gut microbiota. Then, 10 mg/kg AOM was administered through intraperitoneal injection. Seven days later, 2.5% DSS was put in the drinking water for 5 days, followed by 2 weeks without DSS. The 5 days of DSS was then repeated, and the mice were sacrificed 6 weeks after AOM injection. The results showed that sucralose caused significant increases in the number and size of AOM/DSS-induced colorectal tumors along with changes in other parameters such as body and spleen weight, pathological scores, mortality, fecal ß-glucuronidase and digestive proteases, gut barrier molecules, gut microbiota, inflammatory cytokines and pathways (TNFα, IL-1ß, IL-6, IL-10, and TLR4/Myd88/NF-κB signaling), and STAT3/VEGF tumor-associated signaling pathway molecules. These results suggest that sucralose may increase tumorigenesis along with dysbiosis of gut microbiota, impaired inactivation of digestive protease, damage to the gut barrier, and exacerbated inflammation.

14.
J Ophthalmol ; 2019: 8949683, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31073414

RESUMEN

PURPOSE: To compare the prevalence of and factors associated with Demodex brevis and Demodex folliculorum in patients with cylindrical dandruff (CD group) and healthy controls. METHODS: Eyelashes were taken from 1680 patients with CD and 1700 healthy controls in China from March 2015 to May 2017. All patients underwent a complete eye examination, and Demodex spp. were counted. The prevalence was analyzed according to age, gender, and clinical features. RESULTS: Mean patient age was 42.93 ± 16.52 (3-88) and 39.4 ± 13.6 (7-81) years old in the CD and healthy control groups, respectively. In the CD and healthy groups, the positive rate for Demodex folliculorum was 27.92% and 8.47%, respectively, while that for Demodex brevis was 31.67% and 6.65%, respectively. In the CD group, the prevalence of Demodex brevis was higher than that of Demodex folliculorum, no matter in the females (33.65% versus 29.01%) or the males (28.54% versus 23.88%) in the CD group. Moreover, the numbers of Demodex folliculorum and Demodex brevis were significantly and positively correlated with age, in both children and old patients (both P < 0.001), as well as with the severity of eyelid congestion (all P < 0.05). CONCLUSIONS: In a large sample population, the prevalence of Demodex brevis and Demodex folliculorum was higher in the CD group than in healthy volunteers. In addition, the severity of eyelid congestion might be exacerbated by the number of Demodex spp., which may therefore provide a good clinical reference and objective guide.

15.
Curr Eye Res ; 44(10): 1067-1074, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31064234

RESUMEN

Purpose: To determine the prevalence, risk factors and microbial profiles of donor corneal contamination and its association with postoperative infection. Materials and Methods: 1348 hypothermic preserved donor corneas were screened during keratoplasty to assess the impacts of donor age, gender, cause of death and corneal preservation time on the contamination risk. The microbial spectrum and antibiotic sensitivity of causative microorganisms and the prognostic role of corneoscleral rim cultures were analyzed. Results: 111 donor corneas (8.2%) had positive microbial cultures, with 84 contaminated by bacteria, 25 by fungi and 2 by both. Acinetobacter baumannii complex (19.8%) and Candida spp. (9.0%) were the most commonly isolated bacteria and fungi, respectively. Two patients (1.8%) who received contaminated corneal buttons developed postoperative infections. Death due to cardiac disease led to more corneal contaminations than death due to brain disease (odds ratio (OR) = 2.59, P = .009). Longer preservation time was associated with a trend toward increasing contamination rate (from 8.3% to 15.0%). Moreover, fungal-contaminated corneas were preserved longer than bacterial-contaminated corneas (6.6 ± 4.5 versus 10.2 ± 5.4 days, P = .001). Corneas from donors who died from cardiac diseases and trauma showed the highest prevalence of bacterial (10.9%) and fungal (2.6%) contamination, respectively. Antibiotic sensitivity testing revealed that the third-generation fluoroquinolone levofloxacin had high rates of susceptibility to both gram-positive (G+) (60.0%) and gram-negative (G-) (44.6%) bacteria. Conclusions: The causes of donor corneal contamination are multifactorial. The antibiotic resistance rate of contaminating microbes seems to be increasing. Whether antibiotic usage in storage medium and postoperative prophylaxis should be updated accordingly warrants further investigation.


Asunto(s)
Bacterias/aislamiento & purificación , Córnea/microbiología , Infecciones Bacterianas del Ojo/epidemiología , Infecciones Fúngicas del Ojo/epidemiología , Hongos/aislamiento & purificación , Queratoplastia Penetrante , Preservación de Órganos/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bacterias/efectos de los fármacos , Niño , Preescolar , Criopreservación/métodos , Femenino , Hongos/efectos de los fármacos , Humanos , Lactante , Levofloxacino/farmacología , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Técnicas de Cultivo de Órganos , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Donantes de Tejidos
16.
Sci Rep ; 8(1): 16198, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30385808

RESUMEN

Visible light-driven water splitting (VLWS) into hydrogen and oxygen is attractive and depends on efficient photocatalysts. Herein, we demonstrate the first exploration of the capability to control the morphology of nanostructured TiO2 in conjunction with the choice of a suitable plasmonic metal (PM) to fabricate novel photocatalysts that are capable of harvesting visible light for more efficient VL-fuel conversion. This methodology affords us to successful access to the novel plasmonic Pt/TiO2-HA (large Pt nanoparticles (NPs) supported on TiO2 hierarchical nano-architecture (TiO2-HA)) photocatalysts that exhibit plasmon absorption in the visible range and consequent outstanding activity and durability for VLWS. Particularly, the Pt/TiO2-HA shows an excellent photocatalytic activity for overall water splitting rather than only for hydrogen evolution (HE), which is superior to those of the conventional plasmonic Au/TiO2 photocatalysts. The synergistic effects of the high Schottky barrier at the Pt-TiO2-HA interface, which induces the stronger reduction ability of hot electrons, and intrinsic Pt catalytic activity are responsible for the exceptional photocatalytic performance of Pt/TiO2-HA and simplify the composition of plasmonic photocatalysts.

17.
Sci Rep ; 7(1): 16465, 2017 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-29184136

RESUMEN

Shape control of noble metal (NM) nanocrystals (NCs) is of great importance for improving their electrocatalytic performance. In this report, branched Pd@Rh core@shell NCs that have right square prism-like arms with preferential exposure of Rh {100} facets (denoted as b-Pd@Rh-NCs thereafter) are synthesized and utilized as an electrocatalyst for the hydrazine electrooxidation (HEO) in acidic and alkaline electrolytes. The b-Pd@Rh-NCs are obtained by the heteroepitaxial growth of Rh on the pre-formed branched Pd NCs (denoted as b-Pd-NCs thereafter) core in the presence of poly(vinyl pyrrolidone) (PVP) and bromide ions. A comparative analysis of the voltammetric data for the HEO shows a higher activity on the b-Pd@Rh-NCs exposed with Rh {100} faces than on Rh black, the b-Pd-NCs, and Pd black in acid and alkaline solutions, indicating a structure sensitivity of the reaction. Analysis of the products from the b-Pd@Rh-NCs catalysed HEO reveals a very high hydrazine fuel efficiency, as determined by on-line differential electrochemical mass spectrometry (DEMS).

18.
Int J Ophthalmol ; 9(3): 384-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27158607

RESUMEN

AIM: To investigate the spectrum and antibiotic susceptibility of bacteria isolated from patients with suspected corneal infections in Zhongshan Ophthalmic Center in South China over the past four years retrospectively. METHODS: Totally 1943 corneal scrapes from patients with corneal infections from 2010 to 2013 were cultured and processed using standard microbiological procedures to identify bacterial isolates. Simultaneously, the bacterial isolates were tested for antibiotic susceptibility to 8 antibiotics (ceftazidime, cefuroxim, cefazolin, levofloxacin, ofloxacin, neomycin, tobramycin, chloramphenicol) using the Kirby-Bauer disc diffusion technique. RESULTS: Of the total 1943 scrapes, 397 (20.43%) were culture-positive, of which 294 (74.06%) were gram-positive (GP) and 103 (25.94%) were gram-negative (GN) bacteria. Of the GP organisms, the most prevalent genera were Staphylococcus spp. (56.17%, n=223), Kocuria spp. (5.29%, n=21) and Micrococcus spp. (1.26%, n=5). On the other hand, the most prevalent genera were Pseudomonas spp. (12.85%, n=51), Burkholderia spp. (2.02%, n=8) and Acinetobacter spp. (1.51%, n=6) for the GN organisms. Among five antibiotics that have eye drop products, the resistant to neomycin of GP (7.82%, 95% CI: 4.72%-10.92%) and GN isolates (9.71%, 95% CI: 4.01%-15.41%) was lowest, while the resistant to chloramphenicol was highest (GP: 34.35%, 95% CI: 28.92%-39.78%; GN: 60.19%, 95% CI: 50.74%-69.64%). CONCLUSION: Staphylococcus spp. was the most common bacterial pathogens isolated from patients with corneal infections in this setting. High percentages of GP and GN bacteria were mostly susceptible to neomycin and highly resistant to chloramphenicol.

19.
J Ophthalmol ; 2015: 813979, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26576294

RESUMEN

This study aimed to compare the differences of microbial spectrum and antibiotic resistance patterns between external and intraocular bacterial infections in an eye hospital in South China. A total of 737 bacteria isolates from suspected ocular infections were included in this retrospective study covering the period 2010-2013. The organisms cultured from the ocular surface (cornea, conjunctiva) accounted for the majority of the isolates (82.77%, n = 610), followed by the intraocular (aqueous humor, vitreous fluid), which accounted for 17.23% (n = 127). The top three species accounting for the external ocular infections were S. epidermidis (35.25%), P. aeruginosa (8.03%), and S. simulans (4.43%). The top three species for the intraocular infections were S. epidermidis (14.96%), S. hominis (8.66%), and B. subtilis (7.87%). The bacteria from the external ocular surface were more sensitive to neomycin, while those from the intraocular specimens were more sensitive to levofloxacin (P < 0.01). Multidrug resistance was found in 89 bacteria (12.08%), including isolates from both external (13.28%) and intraocular samples (6.30%). The results of this study indicate that the bacteria spectrum of external and intraocular infections is variable in the setting. A high percentage of bacterial organisms were found to be primarily susceptible to neomycin for external infection and levofloxacin for intraocular infection.

20.
J Colloid Interface Sci ; 258(2): 244-51, 2003 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-12618093

RESUMEN

The preparation and characterization of silver nanocrystals by chemical reduction of silver ions in the presence of aniline using hydrazine monohydrate (N(2)H(4).H(2)O) or sodium citrate as the reducing agent are described. A high yield of aniline-derivatized hexagonal silver nanoparticles is obtained by the reduction of Ag(2)SO(4) with N(2)H(4).H(2)O. An alternative strategy is the reduction of Ag(+) by citrate in the presence of aniline, by which the size and morphology of the Ag nanocrystals can be controlled to a certain degree by changing the concentration ratio of aniline to Ag(+). It is believed that the amount of aniline added in the starting solutions for the preparation influences the morphology of the Ag nanoparticles. In addition, the long Ag nanorods with a high mean aspect ratio are prepared in the presence of aniline at a low concentration or o-anisidine.

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