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1.
Zhonghua Er Ke Za Zhi ; 61(12): 1086-1091, 2023 Dec 02.
Artículo en Chino | MEDLINE | ID: mdl-38018045

RESUMEN

Objective: To analyze the clinical characteristics of children with multisystem inflammatory syndrome (MIS-C) associated with SARS-CoV-2 in China, and to improve the understanding of MIS-C among pediatricians. Methods: Case series study.Collect the clinical characteristics, auxiliary examinations, treatment decisions, and prognosis of 64 patients with MIS-C from 9 hospitals in China from December 2022 to June 2023. Results: Among the 64 MIS-C patients, 36 were boys and 28 were girls, with an onset age being 2.8 (0.3, 14.0) years. All patients suffered from fever, elevated inflammatory indicators, and multiple system involvement. Forty-three patients (67%) were involved in more than 3 systems simultaneously, including skin mucosa 60 cases (94%), blood system 52 cases (89%), circulatory system 54 cases (84%), digestive system 48 cases (75%), and nervous system 24 cases (37%). Common mucocutaneous lesions included rash 54 cases (84%) and conjunctival congestion and (or) lip flushing 45 cases (70%). Hematological abnormalities consisted of coagulation dysfunction 48 cases (75%), thrombocytopenia 9 cases (14%), and lymphopenia 8 cases (13%). Cardiovascular lesions mainly affected cardiac function, of which 11 patients (17%) were accompanied by hypotension or shock, and 7 patients (12%) had coronary artery dilatation.Thirty-six patients (56%) had gastrointestinal symptoms, 23 patients (36%) had neurological symptoms. Forty-five patients (70%) received the initial treatment of intravenous immunoglobulin in combination with glucocorticoids, 5 patients (8%) received the methylprednisolone pulse therapy and 2 patients (3%) treated with biological agents, 7 patients with coronary artery dilation all returned to normal within 6 months. Conclusions: MIS-C patients are mainly characterized by fever, high inflammatory response, and multiple organ damage. The preferred initial treatment is intravenous immunoglobulin combined with glucocorticoids. All patients have a good prognosis.


Asunto(s)
COVID-19 , Enfermedades del Tejido Conjuntivo , Aneurisma Coronario , Masculino , Niño , Femenino , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Coagulación Sanguínea , China/epidemiología , Fiebre , Síndrome de Respuesta Inflamatoria Sistémica/diagnóstico , Síndrome de Respuesta Inflamatoria Sistémica/terapia
2.
Zhonghua Er Ke Za Zhi ; 61(12): 1098-1102, 2023 Dec 02.
Artículo en Chino | MEDLINE | ID: mdl-38018047

RESUMEN

Objective: To summarize the clinical characteristics of tumour necrosis factor receptor-associated periodic syndrome (TRAPS) in children. Methods: The clinical manifestations, laboratory tests, genetic testing and follow-up of 10 children with TRAPS from May 2011 to May 2021 in 6 hospitals in China were retrospectively analyzed. Results: Among the 10 patients with TRAPS, including 8 boys and 2 girls. The age of onset was 2 (1, 5) years, the age of diagnosis was (8±4) years, and the time from onset to diagnosis was 3 (1, 7) years. A total of 7 types of TNFRSF1A gene variants were detected, including 5 paternal variations, 1 maternal variation and 4 de novo variations. Six children had a family history of related diseases. Clinical manifestations included recurrent fever in 10 cases, rash in 4 cases, abdominal pain in 6 cases, joint involvement in 6 cases, periorbital edema in 1 case, and myalgia in 4 cases. Two patients had hematological system involvement. The erythrocyte sedimentation rate and C-reactive protein were significantly increased in 10 cases. All patients were negative for autoantibodies. In the course of treatment, 5 cases were treated with glucocorticoids, 7 cases with immunosuppressants, and 7 cases with biological agents. Conclusions: TRAPS is clinically characterized by recurrent fever accompanied by joint, gastrointestinal, skin, and muscle involvement. Inflammatory markers are elevated, and autoantibodies are mostly negative. Treatment mainly involves glucocorticoids, immunosuppressants, and biological agents.


Asunto(s)
Fiebre Mediterránea Familiar , Enfermedades Autoinflamatorias Hereditarias , Masculino , Niño , Femenino , Humanos , Preescolar , Receptores Tipo I de Factores de Necrosis Tumoral/genética , Estudios Retrospectivos , Enfermedades Autoinflamatorias Hereditarias/diagnóstico , Enfermedades Autoinflamatorias Hereditarias/genética , Enfermedades Autoinflamatorias Hereditarias/tratamiento farmacológico , Glucocorticoides/uso terapéutico , Factores Biológicos/uso terapéutico , Inmunosupresores/uso terapéutico , Autoanticuerpos , Fiebre Mediterránea Familiar/diagnóstico , Mutación
3.
Zhonghua Jie He He Hu Xi Za Zhi ; 46(4): 380-387, 2023 Apr 12.
Artículo en Chino | MEDLINE | ID: mdl-36990702

RESUMEN

Objective: To investigate the pathogenic characteristics, bacteriological diagnosis time and its associated factors among patients with nontuberculous mycobacterial (NTM) lung disease in a large tuberculosis-designated hospital in Shanghai from 2020 to 2021, in order to improve diagnosis efficiency and formulate precision treatment. Methods: On the basis of the Tuberculosis Database in Shanghai Pulmonary Hospital, NTM patients diagnosed by the Department of Tuberculosis between January 2020 and December 2021 were screened. Demographic, clinical and bacterial information were retrospectively collected. Chi-square test, paired-sample nonparametric test and logistic regression model were used to analyze the factors associated with the diagnosis time of NTM lung disease. Results: A total of 294 patients with bacteriologically confirmed NTM lung disease were included in this study, 147 males and 147 females with a median age of 61(46, 69) years. Of them, 227 (77.2%) patients had comorbidity of bronchiectasis. Species identification results showed that Mycobacterium Avium-Intracellulare Complex was the main pathogen of NTM lung disease (56.1%), followed by Mycobacterium kansasii (19.0%) and Mycobacterium abscessus (15.3%). Species such as Mycobacterium xenopi and Mycobacterium malmoense were rarely identified, accounting for a total proportion of only 3.1%. Positive culture rates for sputum, bronchoalveolar lavage fluid and puncture fluid were 87.4%, 80.3% and 61.5%, respectively. Paired-sample analysis showed that the positive rate of sputum culture was significantly higher than that of smear microscopy (87.1% vs. 48.4%, P<0.01), while no statistical difference was observed between sputum and bronchoalveolar lavage fluid on positive culture rate (78.7% vs. 77.3%, P>0.05). Patients with cough or expectoration were observed with 4.04-fold (95%CI 1.80-9.05) or 2.95-fold (95%CI 1.34-6.52) higher probability of positive sputum culture, compared to those without. Regarding bronchoalveolar lavage fluid, female or patients with bronchiectasis had a 2.82-fold (95%CI 1.16-6.88) or 2.38-fold (95%CI 1.01-5.63) higher probability to achieve a positive culture. The median time to diagnosis of NTM lung disease was 32 (interquartile range: 26-42) days. The results of multivariable analysis showed that patients with symptom of expectoration (aOR=0.48, 95%CI 0.29-0.80) needed a shorter diagnosis time in comparison with patients without expectoration. With Mycobacterium Avium-Intracellulare Complex as a reference, lung disease caused by Mycobacterium abscessus needed shorter diagnosis time (aOR=0.43, 95%CI 0.21-0.88), whereas those caused by rare NTM species were observed to require a longer diagnosis time (aOR=8.31, 95%CI 1.01-68.6). Conclusion: The main pathogen causing NTM lung disease in Shanghai was Mycobacterium Avium-Intracellulare Complex. Sex, clinical symptoms and bronchiectasis had an impact on the positive rate of mycobacterial culture. The majority of patients in study hospital were timely diagnosed. Clinical symptoms and NTM species were associated with the bacteriological diagnosis time of NTM lung disease.


Asunto(s)
Bronquiectasia , Enfermedades Pulmonares , Infecciones por Mycobacterium no Tuberculosas , Mycobacterium abscessus , Neumonía , Masculino , Humanos , Femenino , Estudios Retrospectivos , China/epidemiología , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Complejo Mycobacterium avium , Enfermedades Pulmonares/tratamiento farmacológico , Hospitales
4.
Artículo en Chino | MEDLINE | ID: mdl-33910286

RESUMEN

Objective: To understand the mastery of occupational hygienic knowledge and the implementing of occupational health protection measures in the group which were exposed to the procedure of manufacture and use in glass fiber company, and to explore the feasibility of the prevention of the skin injury by occupational health education in glass fiber workers. Methods: We selected 257 on-the-job employees as the research object in a ceramic enterprise in Nanjing from June 2018 to August 2019, with the method of cluster random sampling. According to Solomon's design, the intervention group in which we took measures with health education was divided into RG(1) (O(1)XO(2)) and RG(3) (XO(5)) group, and the control group where we didn't take any intervention was divided into RG(2) (O(3)-O(4)) and RG(4) (-O(6)) group. The intervention effect of health education on the occupational protection of glass fiber workers was evaluated by the results of questionnaire. Results: After training, the average score of occupational health knowledge in the intervention group was 27.34 points higher than that before training, the intervention index was 1.42, 23.62-27.73 points higher than the control glass fiber workers and 33.62-35.52 points higher than the control glass non-glass fiber workers; Compared with the control group, the positive attitude rate of fiber glass workers in the intervention group increased by 13.28%, 13.51%, 11.68% and 11.48%, and the intervention indexes were 1.18, 1.17, 1.14 and 1.15, which was corresponding to using protective cream, wearing gloves, wearing working clothes, washing hands and bathing after work, respectively; Compared with the control group, the implementation rate of occupational protection measures which were represented by wearing gloves、washing hands and bathing for glass fiber workers in the intervention group increased by 29.25% and 7.27% respectively, and the intervention indexes were 1.43 and 1.08 respectively; The skin injury rate of fiberglass workers in the intervention group was reduced by 11.43% comparing to the control group, the intervention index was 1.67. Conclusion: According to the occupational health education of fiberglass workers, it improves the mastery of occupational health knowledge, positive atti-tude rate and the implementation rate of occupational protection measures, meanwhile, it reduces the skin injury rate of the intervention objects to a certain extent.


Asunto(s)
Exposición Profesional , Salud Laboral , Vidrio , Educación en Salud , Humanos , Exposición Profesional/prevención & control , Encuestas y Cuestionarios
5.
Qual Life Res ; 28(11): 2957-2967, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31399859

RESUMEN

PURPOSE: Central cancer registries collect data and provide population-level statistics that can be tracked over time; yet registries may not capture the full range of clinically relevant outcomes. Patient-generated health data (PGHD) include health/treatment history, biometrics, and patient-reported outcomes (PROs). Collection of PGHD would broaden registry outcomes to better inform research, policy, and care. However, this is dependent on the willingness of patients to share such data. This study examines cancer survivors' perspectives about sharing PGHD with central cancer registries. METHODS: Three U.S. central registries sampled colorectal, non-Hodgkin lymphoma, and metastatic breast cancer survivors 1-4 years after diagnosis, recruiting them via mail to participate in one of seven focus groups (n = 52). Group discussions were recorded, transcribed, and thematically analyzed. RESULTS: Most survivor-participants were unaware of the existence of registries. After having registries explained, all participants expressed their willingness to share PGHD with them if treated confidentially. Participants were willing to provide information on a variety of topics (e.g., medical history, medications, symptoms, financial difficulties, quality of life, biometrics, nutrition, exercise, and mental health), with a focus on long-term effects of cancer and its treatment. Participants' preferred mode for providing data varied. Participants were also interested in receiving information from registries. CONCLUSIONS: Our results suggest that registry-based collection of PGHD is acceptable to most cancer survivors and could facilitate registry-based efforts to collect PGHD/PROs. Central cancer registry-based collection of PGHD/PROs, especially on long-term effects, could enhance registry support of cancer control efforts including research and population health management.


Asunto(s)
Supervivientes de Cáncer/psicología , Recolección de Datos/métodos , Manejo de Datos/métodos , Atención a la Salud/métodos , Medición de Resultados Informados por el Paciente , Calidad de Vida/psicología , Sistema de Registros/normas , Femenino , Grupos Focales , Humanos , Masculino , Persona de Mediana Edad
7.
Zhonghua Gan Zang Bing Za Zhi ; 24(10): 767-771, 2016 Oct 20.
Artículo en Chino | MEDLINE | ID: mdl-27938563

RESUMEN

Objective: To investigate the effect of nicotinic acetylcholine receptor α7 (α7nAChR) subunit gene on liver inflammation in mice with nonalcoholic steatohepatitis (NASH) and related mechanisms. Methods: C57BL/6J mice and α7nAChR gene knockout mice were fed for 24 weeks to establish the NASH model, and the mice were sacrificed to isolate and culture the primary liver macrophages. After the treatment with nicotine and endotoxin, ELISA was used to measure the levels of the inflammatory factors interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in supernatant; indirect immunofluorescence assay and Western blot were used to observe the effect on the NF-κB signaling pathway, and quantitative PCR was used to measure the mRNA expression of Toll-like receptor-4 (TLR-4) in macrophages. An analysis of variance was used for comparison of means between multiple groups. Results: The results of ELISA showed that compared with the endotoxin+nicotine group of C57 NASH mice, the endotoxin+nicotine group of gene knockout NASH mice had significantly higher levels of IL-6 and TNF-α in supernatant (IL-6: 1 599±65 pg/ml vs 1 465±45 pg/ml, P < 0.05; TNF-α: 1 567±66 pg/ml vs 1 433±50 pg/ml, P < 0.05). The results of Western blot showed that compared with the endotoxin+nicotine group of C57 NASH mice, the endotoxin+nicotine group of gene knockout NASH mice had significantly higher relative protein expression of phosphorylated NF-κB and TLR-4 (NF-κB: 69 425±600 vs 51 133±200, P < 0.05; TLR-4: 93 387±684 vs 64 198±630, P < 0.05). The results of indirect immunofluorescence assay showed that the endotoxin+nicotine group of gene knockout NASH mice had a significantly higher fluorescence intensity of NF-κB than the endotoxin+nicotine group of C57 NASH mice. The results of PCR showed that the endotoxin+nicotine group of gene knockout NASH mice had significantly higher relative mRNA expression of TLR-4 than the endotoxin+nicotine group of C57 NASH mice (4.13±0.13 vs 2.93±0.14, P < 0.05). Conclusion: The α7nAChR gene knockout can aggravate the degree of inflammatory reaction in NASH, and its mechanism may be related to the fact that the NF-κB signaling pathway cannot be inhibited, which aggravates inflammatory reaction.


Asunto(s)
Antiinflamatorios/uso terapéutico , Endotoxinas/uso terapéutico , Inflamación , Hígado/efectos de los fármacos , Nicotina/uso terapéutico , Agonistas Nicotínicos/uso terapéutico , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Receptor Nicotínico de Acetilcolina alfa 7/agonistas , Animales , Modelos Animales de Enfermedad , Hepatitis , Inflamación/tratamiento farmacológico , Inflamación/inmunología , Interleucina-6/inmunología , Hígado/patología , Ratones , Ratones Endogámicos C57BL , FN-kappa B , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/inmunología , Fosforilación , Transducción de Señal , Factor de Necrosis Tumoral alfa/inmunología , Receptor Nicotínico de Acetilcolina alfa 7/inmunología
8.
Beijing Da Xue Xue Bao Yi Xue Ban ; 48(5): 777-782, 2016 10 18.
Artículo en Chino | MEDLINE | ID: mdl-27752155

RESUMEN

OBJECTIVE: To investigate the anti-inflammation effects by activation of the cholinergic anti-inflammatory pathway and its mechanisms in non-alcoholic steatohepatitis (NASH) model mice. METHODS: 6-week-old male C57BL/6J (B6) mice were randomly divided into four groups: the first group was normal mice, injected with saline; the second group was normal mice, injected with nicotine; the third group was NASH model mice, injected with saline; the fourth group was NASH model mice, injected with nicotine. The experimental mice were fed with either standard chow (SC) or high-fat and high-fructose (HFHF) for 17 weeks to generate an NASH model mice. The mice received injection once daily for 3 weeks [nicotine dose, 400 µg/kg]. Then, their pathological characteristics and function of the liver were assessed. The expressions of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in serum were analyzed by enzyme linked immunosorbent assay (ELISA). The expressions of alpha 7 nicotinic acetylcholine receptors (α7nAChR), Toll-like receptors-4 (TLR-4) and nuclear factor κB of phosphory-lation (p-NF-κB) in Kupffer cells were determined by Western blot and immunofluorescence assays. RESULTS: We successfully generated NASH model mice by imitating the high-fat and high-fructose dietary style of NASH patients. The results of our investigation demonstrated that nicotine could reduce significantly the levels of IL-6, and TNF-α in serum (P<0.05). The expression of p-NF-κB protein in the group which was NASH model mice injected with nicotine declined significantly as compared with the group which was NASH model mice injected with saline (P<0.05). And the expression of α7nAChR protein elevated significantly conversely (P<0.05). CONCLUSION: Activation of the cholinergic anti-inflammatory pathway could inhibit the release of inflammatory factors as TNF-α and IL-6 in NASH model mice, and the mechanism for the inhibition of inflammatory was mediated by NF-κB pathway.


Asunto(s)
Interleucina-6/antagonistas & inhibidores , Macrófagos del Hígado/química , FN-kappa B/antagonistas & inhibidores , Nicotina/farmacología , Nicotina/uso terapéutico , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Animales , Dieta de Carga de Carbohidratos/efectos adversos , Dieta Alta en Grasa/efectos adversos , Grasas de la Dieta/efectos adversos , Modelos Animales de Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/inmunología , Fructosa/efectos adversos , Inflamación/tratamiento farmacológico , Interleucina-6/sangre , Hígado/efectos de los fármacos , Hígado/patología , Masculino , Ratones , Ratones Endogámicos C57BL , FN-kappa B/análisis , Enfermedad del Hígado Graso no Alcohólico/inducido químicamente , Enfermedad del Hígado Graso no Alcohólico/patología , Enfermedad del Hígado Graso no Alcohólico/fisiopatología , Receptor Toll-Like 4/análisis , Factor de Necrosis Tumoral alfa/sangre , Receptor Nicotínico de Acetilcolina alfa 7/análisis
9.
Clin Oncol (R Coll Radiol) ; 27(6): 337-44, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25736278

RESUMEN

AIMS: Several studies have evaluated the association between smoking and p53 mutation in oesophageal squamous cell carcinoma (ESCC), but the conclusions are inconsistent. The aim of the present study was to carry out a meta-analysis evaluating the relationship between smoking and p53 mutation in patients with ESCC. MATERIALS AND METHODS: Eligible studies were identified through searches in PubMed and EMBASE. The odds ratio with 95% confidence interval was used to assess the association. In total, 20 studies were identified that met the selection criteria; these studies were analysed using STATA 12.0 software. RESULTS: The 20 studies identified comprised 1524 ESCC patients, of whom 72.97% were smokers and 27.03% were non-smokers. The pooled odds ratio of p53 mutation in ESCC for any cigarette smoking versus no smoking was 1.28 (95% confidence interval=0.88-1.88). The estimated odds ratios were 1.06 (95% confidence interval=0.56-2.00, based on five studies, 129 light smokers and 70 non-smokers) for light smoking and 2.01 (95% confidence interval=1.12-3.60, based on five studies, 223 heavy smokers and 73 non-smokers) for heavy smoking. CONCLUSION: The results of our meta-analysis indicate an overall positive relationship between heavy smoking and p53 mutation in ESCC. Heavy smokers with ESCC have a higher risk for p53 mutation than non-smokers. Large-scale clinical studies are still needed to draw a more precise conclusion.


Asunto(s)
Carcinoma de Células Escamosas/etiología , Neoplasias Esofágicas/etiología , Mutación/genética , Fumar/efectos adversos , Fumar/genética , Proteína p53 Supresora de Tumor/genética , Humanos , Factores de Riesgo
10.
Nanotechnology ; 24(17): 175701, 2013 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-23548821

RESUMEN

Centimeter-long Ta3N5 nanobelts were synthesized by a reaction of centimeter-long TaS3 nanobelt templates with flowing NH3 at 800 °C for 2 h. The nanobelts have cross-sections of about 50 × 100 nm(2), and lengths up to 0.5 cm. A field effect transistor (FET) made of a single Ta3N5 nanobelt was fabricated on silica/silicon substrate. The electric transport of the individual nanobelt revealed that the nanobelt is a semiconductor with a room-temperature resistivity of 11.88 Ω m, and can be fitted well with an empirical formula ρ = 10831 exp(-T/43.8) - 22.6, where ρ is resistivity (Ω m) and T is absolute temperature (K). The FET showed decent photoconductive performance under light irradiation in the range 250-630 nm. The photocurrent increased by nearly 10 times the dark current under 450 nm light irradiation at an applied voltage of 5.0 V.

11.
Transplant Proc ; 43(5): 1607-11, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21693241

RESUMEN

BACKGROUND: Posttransplantation diabetes mellitus (PTDM) is a well-recognized renal transplantation complication that is associated with increased graft loss, morbidity, and mortality. Adiponectin gene polymorphisms are associated with type 2 diabetes. However, it remains unknown whether these polymorphisms increase the risk for development of PTDM. Therefore, the aim of this study was to investigate the association between the adiponectin gene polymorphism and the risk of PTDM among Chinese renal allograft recipients. METHODS: We genotyped 398 unrelated renal allograft recipients without a prior diagnosis of diabetes, including 97 PTDM and 301 without PTDM, for adiponectin gene variants: single nucleotide polymorphisms at position 45 and 276, that is, SNP-45: T/G, SNP-276: G/T, using the polymerase chain reaction-restriction fragment length polymorphism assay. No prisoners or organs from prisoners were used in the study. RESULTS: The G allele of SNP-276 was significantly more frequent in PTDM than non-PTDM subjects (P = .041). For SNP-45 and SNP-276, the incidence of PTDM was significantly higher in patients with the GG genotype than those with the TG and TT genotypes (48.1% vs 21.5% and 23.6% and 30.7% vs 18.5% and 22.8%; (P = .011 and .024, respectively). Even after adjusting for age and sex, the effects of the SNP-45 genotypes for GG compared to TT (odds ratio [OR] = 3.108, P = .009) and GG compared to TG (OR = 3.620, P = .004) as well as for SNP-276 genotypes GG compared to TG (OR = 2.203, P = .002) and body mass index at transplantation (OR = 1.099, P = .024) remained significant. CONCLUSIONS: These data suggested that SNP-45 and SNP-276 of the adiponectin gene were significantly associated with an increased risk for PTDM among Chinese renal allograft recipients.


Asunto(s)
Adiponectina/genética , Complicaciones de la Diabetes/genética , Trasplante de Riñón/efectos adversos , Polimorfismo de Nucleótido Simple , Adulto , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trasplante Homólogo
12.
J Appl Microbiol ; 110(2): 422-30, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21091594

RESUMEN

AIMS: To improve a commercially used strain for gellan production by exogenous Vitreoscilla haemoglobin (VHb). METHODS AND RESULTS: VHb gene was expressed in Sphingomonas elodea under the control of constitutive bla promoter. Biochemical activity of expressed VHb was confirmed by CO-difference spectra analysis that exhibited a characteristic absorption maximum at 419 nm. During cultivation, not only enhanced cell growth was detected, but also 20% improvement in gellan production was observed after 48 h of incubation, with a maximum yield of 16·82 g l(-1). Moreover, maximum sucrose conversion efficiency (g gellan per g sucrose) was 57·8, 20% higher than that of the parental strain. We further examined the polysaccharide production of VHb-expressing strain at different aeration levels in Erlenmeyer flasks. Again, in all cases, a significant enhancement of gellan production was observed, and the enhancement was more significant under oxygen-limiting conditions (up to 26·8%). CONCLUSIONS: VHb exhibited positive effect on cell growth and gellan yield of S. elodea, especially under hypoxic conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first application of VHb as an effective metabolic engineering strategy in S. elodea to regulate cell growth and optimize gellan yield.


Asunto(s)
Proteínas Bacterianas/metabolismo , Polisacáridos Bacterianos/biosíntesis , Sphingomonas/metabolismo , Hemoglobinas Truncadas/metabolismo , Proteínas Bacterianas/genética , Reactores Biológicos , Fermentación , Sphingomonas/genética , Sphingomonas/crecimiento & desarrollo , Hemoglobinas Truncadas/genética
13.
Nano Lett ; 6(10): 2375-8, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17034114

RESUMEN

We demonstrate a low-cost and effective method to fabricate hexagonally patterned, vertically aligned ZnO nanorod arrays. Selective wet-etching is used to develop the catalyzing gold particle hexagonal pattern with the aid of a polystyrene microsphere self-assembled monolayer. The gold particles have tunable sizes independent of the polystyrene microsphere's diameter and are inherently round in shape. Each ZnO rod is grown individually from a catalyzing site via catalyst-initiated epitaxy, and the original hexagonal periodicity is well-preserved. The rods have flat ends, and the diameters of the rods can be controlled well by the amount of source materials. This method provides a promising way to create ZnO one-dimensional nanostructures for applications as two-dimensional photonic crystal, sensor arrays, nanolaser arrays, and optoelectronic devices.


Asunto(s)
Cristalización/métodos , Nanoestructuras/química , Nanoestructuras/ultraestructura , Nanotecnología/métodos , Poliestirenos/química , Óxido de Zinc/química , Ensayo de Materiales , Microesferas , Conformación Molecular , Tamaño de la Partícula , Propiedades de Superficie
14.
IEEE Trans Nanobioscience ; 5(3): 204-9, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16999246

RESUMEN

Hydrogen sulfide is a colorless and flammable gas under room temperature. Usually hydrogen sulfide is considered to be toxic; however, the recent research revealed that hydrogen sulfide in the cardiovascular system plays the role of a vascular dilator. The physiological role of hydrogen sulfide depends on its in vivo level. As such, the measurement of hydrogen sulfide with nano-quantity resolution becomes an important subject. Existing methods generally require bulky samples and are invasive and offline. It will be significantly helpful to measure hydrogen sulfide with a small amount of tissue in a noninvasive method The first attempt was to take a blood or serum sample with a trace amount to examine the interaction between hydrogen sulfide and carbon nanotube. The carbon nanotube is chosen because of a known fact that hydrogen sulfide can be adsorbed by activated carbon. The carbon nanotube is an excellent activated carbon in this regard. Fluorescence intensity of the carbon nanotube with and without immersion of it in a hydrogen sulfide medium was examined in the study. It was found that the intensities increase as the concentrations of hydrogen sulfide increase. Furthermore, the concentration of 10 microM hydrogen sulfide in water was successfully measured.


Asunto(s)
Técnicas Biosensibles/métodos , Sulfuro de Hidrógeno/química , Sulfuro de Hidrógeno/aislamiento & purificación , Nanotubos/química , Espectrometría Raman/métodos , Agua/química , Absorción , Mezclas Complejas/análisis , Mezclas Complejas/química , Nanotubos/ultraestructura , Tamaño de la Partícula , Soluciones
15.
Artículo en Inglés | MEDLINE | ID: mdl-16541194

RESUMEN

The effects of berberine (BBR) on the pharmacokinetics of ciclosporin A (CsA) were examined in healthy volunteers. Six healthy male volunteers were orally treated with 0.3 g BBR, twice daily for 10 days. Pharmacokinetic investigations on CsA at 6 mg/kg were done both before and at the end of the BBR treatment period. Another six healthy male volunteers were involved in the pharmacokinetic study with 3 mg CsA/kg, in which the subjects orally received the second single dose of 3 mg CsA/kg, followed by a single oral dose of 0.3 g BBR. The blood CsA concentrations were determined by fluorescence polarization immunoassay. In the pharmacokinetic study with 6 mg CsA/kg, BBR caused no significant changes in the pharmacokinetic parameters of CsA. However, in the trial with 3 mg CsA/kg, the average percentage increase in area under the blood concentration-time curve of CsA was 19.2% (P < 0.05) and the mean C12 increased to 123 microg/l from 104 microg/l (P < 0.05), without altering elimination half-life (t(1/2)), maximum blood drug concentration (Cmax), time to Cmax (tmax), apparent oral clearance (CL/F). The present results suggest that BBR can increase the oral bioavailability of CsA at the dosage of 3 mg/kg. The BBR-mediated increase in CsA bioavailability may be partly attributed to a decrease in liver and/or intestinal metabolism through the inhibition of CYP3A4 in the liver and/or gut wall. The BBR-induced increase in emptying time of stomach and small intestine might be another reason for the increase in CsA bioavailability. However, the speculation should be proved by further investigation.


Asunto(s)
Berberina/farmacología , Ciclosporina/farmacocinética , Inhibidores Enzimáticos del Citocromo P-450 , Inhibidores Enzimáticos/farmacología , Adulto , Disponibilidad Biológica , Citocromo P-450 CYP3A , Sistema Enzimático del Citocromo P-450/metabolismo , Interacciones Farmacológicas , Vaciamiento Gástrico/efectos de los fármacos , Humanos , Intestino Delgado/enzimología , Hígado/enzimología , Masculino
16.
Br J Cancer ; 92(11): 2084-8, 2005 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-15886703

RESUMEN

Acute lymphocytic leukaemia (ALL) incidence among children under 5 years of age was examined, utilising data from 24 United States cancer registries. County-based incidence rates among white children were compared across four levels of urbanisation: large and small metropolitan counties, and adjacent and nonadjacent rural counties. In metropolitan areas, the incidence of ALL was lower among blacks (rate ratio (RR)=0.38, confidence interval (CI)=0.33-0.44) and among Asians/Pacific Islanders (RR=0.78, CI=0.63-0.97) than among whites. Among white children, the incidence of ALL decreased across the four strata of urbanisation, from 67 to 62 to 65 to 54 cases per million person-years at-risk (two-sided trend P=0.009), such that rates were significantly lower in the most remote rural counties than in the most populous metropolitan counties (RR=0.80, 95% CI=0.70-0.91).


Asunto(s)
Ciudades , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiología , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiología , Sistema de Registros/estadística & datos numéricos , Preescolar , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Oportunidad Relativa , Estados Unidos/epidemiología , Población Urbana
17.
J Phys Chem B ; 109(1): 230-9, 2005 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-16851009

RESUMEN

CdS/dendrimer nanocomposites can be synthesized from methanolic Cd(2+) and S(2-) with amine-terminated polyamidoamine dendrimers of generation 8 (G8NH(2)) as stabilizers. By controlling the preparation conditions, nanoparticles with diameters < or = 2 nm can be obtained with a narrow size distribution. They show blue photoluminescence at approximately 450 nm. We studied the effects of various additives on the photoluminescence and elucidated its mechanism. Stable aggregates of two to three G8NH(2) molecules with several CdS nanoparticles form; the particles are located at the surface of the G8NH(2) molecules. The adsorption of the CdS/G8NH(2) nanocomposites on flat substrate surfaces is determined by the substrate chemistry. The hydrophilic nature of G8NH(2) results in weak affinity to graphite but strong affinity to hydroxy-terminated substrates such as mica, oxidized silicon wafers, and carboxylate-terminated monolayers. Patterning of nanocomposites on these hydrophilic substrates is achieved by the microcontact printing method. We propose to use only one molecule, a large dendrimer, to control the nanoparticle formation and also the immobilization of the synthesized nanoparticle/dendrimer composites.


Asunto(s)
Compuestos de Cadmio/química , Compuestos de Cadmio/síntesis química , Dendrímeros/química , Dendrímeros/síntesis química , Nanoestructuras/química , Sulfuros/química , Sulfuros/síntesis química , Adsorción , Luminiscencia , Tamaño de la Partícula , Fotoquímica
18.
Clin Exp Immunol ; 137(3): 486-95, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15320897

RESUMEN

Dendritic cells (DC) represent a phenotypically heterogeneous population endowed with two important biological functions, immunity and tolerance. Here we report that the injection of splenic CD8alpha(+) DC, derived from rats with experimental allergic encephalomyelitis (EAE), delayed the onset and suppressed the severity of EAE in Lewis rats. This was accompanied by the lack of magnetic resonance imaging (MRI) lesions in the brain and spinal cord and by reduced numbers of inflammatory cells within the central nervous system. Injection of CD8(alpha+) DC inhibited T cell proliferation that may relate to increased interferon (IFN)-gamma and nitric oxide production. Although CD8(+)CD28(-) suppressor T cells, apoptotic cells and co-stimulatory molecules were not altered, CD4(+) T cells expressing interleukin (IL)-10 were augmented in rats receiving CD8alpha(+) DC compared to rats receiving total DC or medium. These results demonstrate that rat splenic CD8alpha(+) DC could provide a cellular basis for a novel, individualized immunotherapy using autologous DC as a complement to conventional therapy in diseases with an autoimmune background such as multiple sclerosis.


Asunto(s)
Antígenos CD8/inmunología , Células Dendríticas/trasplante , Encefalomielitis Autoinmune Experimental/inmunología , Animales , Encéfalo/patología , Células Dendríticas/inmunología , Encefalomielitis Autoinmune Experimental/patología , Femenino , Tolerancia Inmunológica , Inmunización Pasiva/métodos , Inmunofenotipificación , Interferón gamma/inmunología , Interleucina-10/inmunología , Imagen por Resonancia Magnética , Ratas , Ratas Endogámicas Lew , Médula Espinal/patología , Subgrupos de Linfocitos T/inmunología
19.
Biomaterials ; 24(11): 1889-96, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12615479

RESUMEN

Ultrahigh molecular weight polyethylene (UHMWPE)/quartz composites were compression molded in the presence of organosiloxane, and then hydrolyzed. The used organosiloxane is vinyl tri-ethyloxyl silane. The gelation, the melting behavior, the crystallinity, the mechanical properties and the wear resistance of UHMWPE/quartz composites were investigated. The results showed that organosiloxane can act as a cross-linking agent for UHMWPE matrix and serve as a coupling agent for improving the bonding between the quartz particles and the UHMWPE matrix. The correlation between the various properties and the morphology of the composites has been discussed. At about 0.5phr organsiloxane while the degree of crystallinity of the composite is at the peak value of 57%, the mechanical properties and the wear resistance of UHMWPE/quartz composites reaches their maximum.


Asunto(s)
Pruebas de Dureza/métodos , Células Musculares/efectos de los fármacos , Polietilenos/química , Polietilenos/toxicidad , Cuarzo/química , Cuarzo/toxicidad , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/química , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Fenómenos Químicos , Química , Análisis de Falla de Equipo , Dureza , Humanos , Materiales Manufacturados , Ensayo de Materiales , Células Musculares/patología , Prótesis e Implantes , Siloxanos/química , Propiedades de Superficie , Temperatura
20.
J Mater Sci Mater Med ; 13(11): 1065-9, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15348177

RESUMEN

Ultra high molecular weight polyethylene (UHMWPE) crosslinked by organosilane was thermal compression molded. The organosilane used was the tri-ethyloxyl vinyl silane. Its gelation, melting behavior, crystallinity, mechanical and wear-resisting properties were systematically investigated. The results showed that the gel ratio of UHMWPE increases with the incorporation of organosilane. At a low content of organosilane, the melting point and crystallinity of the crosslinked UHMWPE increase, and hence the mechanical and wear-resisting properties are improved. However, at a high content of organosilane, these performances of the crosslinked UHMWPE become worse. At 0.4 phr silane, the wear resistance of crosslinked UHMWPE reaches its optimum value.

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