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1.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(1): 24-30, 2024 Jan 12.
Artículo en Zh | MEDLINE | ID: mdl-38062690

RESUMEN

Objective: To analyze the clinical data of a case of lung adenocarcinoma with Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) resistance transforming into sarcoma, and to conduct a literature review to improve the understanding of the resistance mechanism. Histological transformation is a unique form of acquired resistance of EGFR-TKIs in non-small cell lung cancer (NSCLC). Thereinto, the transformation of small cell carcinoma is more common, and the transformation of sarcoma is rarely reported. Methods: Clinicopathological data on the treatment process, pathological features, and clinical outcome of the patient with EGFR-TKIs-resistance lung adenocarcinoma transforming into sarcoma were collected. The literature was reviewed to analyze the pathogenetic mechanism for sarcomatoid carcinoma or sarcoma transformation after drug resistance of adenocarcinoma, as well as the clinical characteristics of the patients and the corresponding therapeutic schemes. Results: We reported a patient with lung adenocarcinoma who developed EGFR-T790M mutation after first-line treatment with icotinib and sarcoma transformation after second-line treatment with almonertinib. Chemotherapy, radioactive particle implantation, antiangiogenic therapy and immunotherapy were followed, but the results were unsatisfactory. There was no report of EGFR-TKIs-resistant lung adenocarcinoma transforming into sarcoma. Among the 14 reports of adenocarcinoma transforming into sarcomatoid carcinoma, 8 cases had EGFR mutation, 3 cases had ALK mutation, 2 cases had ROS1 mutation, and 1 case had no asscoiated sensitive mutation. The median survival of 14 patients with adenocarcinoma transforming to sarcomatoid carcinoma was only 3 months. Conclusions: Sarcoma transformation can be one of the forms of drug resistance in patients with lung adenocarcinoma with EGFR-TKIs. The prognosis of patients with adenocarcinoma after transformation into sarcoma is poor.


Asunto(s)
Adenocarcinoma del Pulmón , Adenocarcinoma , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Sarcoma , Humanos , Adenocarcinoma/genética , Adenocarcinoma del Pulmón/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Resistencia a Antineoplásicos , Receptores ErbB/genética , Neoplasias Pulmonares/patología , Mutación , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Tirosina Quinasas/genética , Proteínas Proto-Oncogénicas/genética , Sarcoma/genética , Sarcoma/tratamiento farmacológico
2.
Public Health ; 225: 110-119, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37924635

RESUMEN

OBJECTIVES: This study aimed to establish an occupational disease surveillance system by identifying high-risk industries for silicosis in Taiwan using a national database linkage approach. METHODS: The study was based on a comprehensive analysis of benefit claims from the National Labor Insurance Research Database and medical records from the National Health Insurance Research Database between 2004 and 2020, providing coverage for more than 88.5% of the workforce and 99.9% of citizens. Silicosis was defined as having received compensation for labor insurance benefits or having received a diagnosis of silicosis (International Classification of Diseases, 10th Revision: J62 or International Classification of Diseases, Ninth Revision: 502). The study used the International Standard Industrial Classification of All Economic Activities for industry-specific classification. Cox proportional hazard models were used to compare the silicosis incidence and risk among each industry and identify high-risk industries for silicosis. RESULTS: This study analyzed 1466 cases of silicosis between 2004 and 2020 and found that 28 industries had incidence rates of over 40 cases per 100,000 workers, indicating more than double the risk of developing silicosis. Of these industries, 14 were considered high risk (relative risk of over four times). Among these, this study identified industries rarely mentioned in the past, such as wholesale of brick, sand, cement, and products, artistic creation, landscape construction, and materials recovery. Stratification by years of work experience reveals those industries such as quarrying of stone, sand, clay, and other mining, construction of buildings, landscape construction, site preparation, foundation and structure construction, building completion and finishing, manufacture of ships, boats, and floating structures, and plumbing, heat, and air conditioning installation display higher hazard ratios for individuals with <10 years of work experience. CONCLUSIONS: The current surveillance system has identified certain industries that are at a higher risk of developing silicosis, which could be used for future occupational epidemiological surveys and targeted preventive measures in these sectors.


Asunto(s)
Enfermedades Profesionales , Exposición Profesional , Silicosis , Humanos , Incidencia , Arena , Taiwán/epidemiología , Silicosis/epidemiología , Silicosis/diagnóstico , Silicosis/prevención & control , Enfermedades Profesionales/epidemiología , Exposición Profesional/efectos adversos
3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(2): 129-132, 2020 Feb 06.
Artículo en Zh | MEDLINE | ID: mdl-32074697

RESUMEN

Objective: To explore the association between the frequency of prenatal care in childbearing aged women and risk of small for gestational age (SGA) among neonatal twins in Shaanxi Province. Methods: From July to December 2013, a total of 30 027 childbearing aged women, who were pregnant from January 2010 to November 2013 and had definite outcomes, were selected from 30 districts (counties) of Shaanxi Province by using the multi-stage random sampling method. The questionnaires with a face-to-face survey method were used to retrospectively collect demographic information, pregnancy history, lifestyle during pregnancy, disease history, nutritional supplements, and health care during pregnancy. Information on the gestational age and birth weight of the newborn were obtained by consulting the medical certificate of birth and were registered as twin A and twin B by birth order. Finally, 356 childbearing aged women and their twin babies with complete data were included in the analysis. A generalized estimation equation model was used to analyze the association between the frequency of prenatal care and the risk of SGA among neonatal twins. Results: The age of childbearing aged women was (27.44±4.68) years old, of which 79.49% (283 women) were rural residents and 44.38% (158 women) had seven or more times prenatal care. The gestational age and birth weight were (37.64±2.51) weeks and (2 510±497) g, respectively. The prevalence of SGA was 51.40% (183/356) for twin A and 53.37% (190/356) for twin B, respectively. The prevalence of SGA was 44.30% (70/158) for twin A with seven or more times prenatal care and 42.41% (67/158) for twin B with seven or more times prenatal care, which was lower than that for twins with less than seven times prenatal care, respectively [57.07% (113/198) and 62.12% (123/198)] (P values were 0.017 and <0.001). The results of generalized estimation equation model suggested that compared to those with less than seven times prenatal care, after adjusting for parity, birth order, place of residence, maternal age, occupation, education, family wealth index, passive smoking, pregnancy-induced hypertension syndrome, folic acid, and iron supplement during perinatal period, and gender of the newborn, the OR (95%CI) of risk of SGA among childbearing aged women with seven or more times prenatal care was 0.60 (0.40-0.91). Conclusion: Seven or more times prenatal care could reduce the risk of SGA among neonatal twins in Shanxi Province.


Asunto(s)
Recién Nacido Pequeño para la Edad Gestacional , Atención Prenatal/estadística & datos numéricos , Gemelos/estadística & datos numéricos , Adulto , China/epidemiología , Femenino , Humanos , Recién Nacido , Embarazo , Estudios Retrospectivos , Medición de Riesgo , Adulto Joven
4.
Tumour Biol ; 34(2): 953-61, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23412975

RESUMEN

Valosin-containing protein (VCP), or p97, is a member of the ATP-binding protein family, and is involved in numerous cellular events, such as, protein degradation, membrane fusion, and chaperone activity. VCP has been demonstrated playing a critical role in non-small-cell lung cancer (NSCLC) pathogenesis and progression recently. We investigated the association between VCP polymorphisms and clinical outcome in advanced NSCLC patients undergoing platinum-based chemotherapy. We recruited 663 Chinese advanced NSCLC patients who were treated with platinum-based regimens, and using their clinical data, we assessed the efficacy and side effects of their treatment. Three tag-single nucleotide polymorphisms (SNPs) of VCP were genotyped. SNP rs2074549 showed a significant association with severe neutropenia. Its G/G genotype increased the risk of grade 3 or 4 neutropenia compared with wild-type homozygotes A/A (P = .001, odds ratio = 2.975). Haplotype association analysis revealed that CGA was associated with the increased incidence of severe neutropenia (P = .041, odds ratio = 1.439). However, no significant relationship was found between the presence of VCP polymorphisms and treatment efficacy when objective response, progression-free survival, and overall survival (OS) were evaluated. Our study is the first to provide evidence that VCP polymorphisms are associated with a severe chemotherapy-related adverse outcome in platinum-treated advanced NSCLC patients.


Asunto(s)
Adenosina Trifosfatasas/genética , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Proteínas de Ciclo Celular/genética , Neoplasias Pulmonares/mortalidad , Compuestos Organoplatinos/efectos adversos , Polimorfismo de Nucleótido Simple/genética , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidad , ADN/sangre , ADN/genética , Femenino , Estudios de Seguimiento , Haplotipos/genética , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neutropenia/inducido químicamente , Reacción en Cadena de la Polimerasa , Pronóstico , Tasa de Supervivencia , Proteína que Contiene Valosina
5.
Dis Esophagus ; 24(3): 131-7, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20946132

RESUMEN

Foreign bodies should not be allowed to remain in the esophagus beyond 24 hours after presentation. However, some patients with esophageal foreign body ingestion do not come to the hospital immediately and may delay medical intervention from the time of ingestion. The aim of this study was to investigate the outcomes of adults with suspected esophageal foreign body ingestion according to the time of ingestion and types of foreign bodies. A total of 326 adult patients (151 men and 175 women) were analyzed, and divided into two groups according to the time period: within or beyond 24 hours from ingestion to endoscopic intervention. A total of 172 patients (52.7%) were found to have ingested foreign bodies; 73.5% were removed smoothly, 10.3% were treated by push technique and 16.0% with failed retrieval received alternative treatments. A higher proportion of patients in the beyond-24 hours group suffered from odynophagia (25.9 vs. 12.9%, P < 0.05). Negative identification of esophageal foreign bodies was more frequent in the beyond-24 hours group (67 vs. 40.2%, P < 0.05), but these patients showed higher proportions of esophageal ulcers (21.1 vs. 7.2%, P < 0.05). The beyond-24 hours group also showed a significantly higher rate of foreign bodies in the lower esophagus (40.0 vs. 15.3%, P < 0.05). Patients with esophageal food bolus impaction had significant delayed endoscopic intervention, longer therapeutic endoscopic time, higher proportions of esophageal cancer, stricture and fewer complications. Endoscopic intervention within 24 hours from the time of ingestion should be considered early in adults, because delaying intervention may produce more symptomatic esophageal ulcerations with odynophagia.


Asunto(s)
Esófago , Cuerpos Extraños/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Esofagoscopía , Femenino , Alimentos , Cuerpos Extraños/complicaciones , Cuerpos Extraños/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
6.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(4): 651-655, 2021 Apr 10.
Artículo en Zh | MEDLINE | ID: mdl-34814445

RESUMEN

Objective: This study explored the association between antenatal calcium supplementation in the childbearing aged women and risk of small for gestational age infant (SGA) among singleton in Shaanxi province,China. Methods: Multi-stage random cluster sampling method was employed to collect information about pregnant women, who were pregnant and had definite outcomes, and their infants, from 30 districts (counties) in 2010 to 2013. Information was collected by face-to-face questionnaire survey. Generalized linear mixed models were employed after adjusting covariates. Dependent variable was whether single-birth neonate was SGA, and independent variable was calcium supplementation of childbearing aged women in different pregnant periods. Results: A total of 28 357 childbearing aged women was recruited in this study. The age of these women was (28.08±4.74) years old, of which, 79.28% were rural residents and 60.90% had calcium supplementation intake. There was a number of 12 810 female in singleton neonates. The neonatal birth weight and gestational age were (3.27±0.16) kg and (277.44±8.80) day, respectively. The prevalence of SGA was 11.35% in total, and 10.48% in mothers with maternal calcium supplementation and 12.70% in mothers without maternal calcium supplementation in whole antenatal period. There were statistically significant differences seen in antenatal calcium supplementation within the subgroups of maternal age (whether the mother was an advanced maternal woman), residential area, maternal occupation, maternal parity, maternal education level, and household incomes (P<0.05). After adjusting these covariates, the risk of SGA among childbearing aged women with antenatal calcium supplementation showed 16% decreased risk (OR=0.84, 95%CI: 0.77-0.92). Further analysis of the different antenatal periods showed that calcium supplementation during the second and third trimester had a statistically significant difference in reducing the risk of neonatal SGA (P<0.05). Besides, subgroup analysis showed that there was a statistically significant difference between the perinatal calcium supplementation and the single-born neonates with SGA Significance (P<0.05) in non-advanced women, those who had a low education level and moderate household economic status groups. Conclusion: The risk reduction of SGA among singleton neonates is related to calcium supplementation during antenatal period in Shaanxi province.


Asunto(s)
Calcio , Ácido Fólico , Adulto , Anciano , Suplementos Dietéticos , Femenino , Edad Gestacional , Humanos , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Embarazo , Adulto Joven
7.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(9): 1542-1549, 2020 Sep 10.
Artículo en Zh | MEDLINE | ID: mdl-33076615

RESUMEN

Cohort study is one of the basic methods used in epidemiological research. With the development of the etiological analysis of complex diseases such as cardiovascular diseases, large natural population-based cohort study has become a popular topic in medical research. In the process of cohort development, one of the important issues is to ensure the efficiency and safety on data collection. As a database management system, with open source, free clinical research data collection and high quality, REDCap can widely be applied in large population-based cohort studies. This article summarizes the baseline survey and follow-up procedures on cohort studies and introduces a REDCap-system-based solution for data collection and management. Contents on the establishment of data working groups, data collection, cohort follow-up methods and field application are also discussed in this paper, in order to improve the efficiency of data collection and management in cohort study to help the development of cohort study in China.


Asunto(s)
Estudios de Cohortes , Recolección de Datos , China/epidemiología , Recolección de Datos/métodos , Humanos , Proyectos de Investigación
8.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(9): 1130-1133, 2019 Sep 10.
Artículo en Zh | MEDLINE | ID: mdl-31594159

RESUMEN

Objective: To investigate the relationship between maternal disease in early pregnancy of women of childbearing age and congenital heart disease of neonates. Methods: A cross-sectional design was used in this study and stratified multistage random sampling method was used. A questionnaire survey was conducted in the childbearing-aged women during 2010-2013 in Shaanxi province. Propensity score (PS) matched (1∶1) analysis was used to match participants with diseases to those without disease in early pregnancy. Through the control of the confounders step by step, a logistic regression model was established to evaluate the ORs of congenital heart disease according to the independent variable of maternal disease. Results: A total of 28 680 pairs of mothers and infants were included in this study, the proportion of the women with disease in early pregnancy was 20.25% (5 807). After PS matching, 5 436 pairs were matched. After adjusting all confounding factors, the multivariable logistic regression analysis results showed that maternal disease (OR=1.86, 95%CI: 1.23-2.81), especially cold (OR=2.19, 95%CI: 1.46-3.28), gynecological disease (OR=4.74, 95%CI: 2.03-11.09) and diabetes (OR=14.00, 95%CI: 1.64-119.21), in early pregnancy were the risk factors for congenital heart disease of neonate. Conclusion: In women of childbearing age, disease in early pregnancy, especially cold, gynecological disease and diabetes, can increase the risk of congenital heart disease in neonates.


Asunto(s)
Cardiopatías/epidemiología , Madres , Estudios Transversales , Femenino , Cardiopatías/congénito , Humanos , Lactante , Recién Nacido , Embarazo , Factores de Riesgo , Encuestas y Cuestionarios
9.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(5): 554-558, 2019 May 10.
Artículo en Zh | MEDLINE | ID: mdl-31177737

RESUMEN

Objective: To understand the relationship between medication during pregnancy and single live preterm birth of infant in women of childbearing age in Shaanxi province. Methods: A cross-sectional design was used in this study and stratified multistage random sampling method was used. A questionnaire survey was conducted in the childbearing-aged women selected through multi stage stratified random sampling in Shaanxi during 2010 to 2013. Qualitative datum was described by percentage and measurement datum was described by mean±standard deviation. Logistic regression analysis was done to evaluate the relationship between medication during pregnancy and preterm birth of infant. Results: The overall incidence rate of premature birth was 2.7% in Shaanxi. Among the 28 841 mothers participating in this study, the proportion of medication use at any time during pregnancy was 15.8%, and the most commonly used drug was cold medicine (5.9%). After adjusting all confounding factors, the multivariable logistic regression analysis results showed that taking hormone medicine (OR=2.23, 95%CI: 1.19-4.18), antihypertensive medicine (OR=7.74, 95%CI: 4.28-13.95) and other medicines (OR=2.15, 95%CI: 1.60-2.89) during early pregnancy were the risk factors for preterm delivery, the risk was 2.23 times, 7.74 times and 2.15 times higher compared with those taking no these medicines. Conclusion: Using hormone medicine, antihypertensive medicine and other medicines during pregnancy increased the risk for preterm delivery in women of childbearing age in Shaanxi.


Asunto(s)
Medicamentos sin Prescripción/administración & dosificación , Complicaciones del Embarazo/epidemiología , Nacimiento Prematuro/epidemiología , Medicamentos bajo Prescripción/administración & dosificación , Antihipertensivos/administración & dosificación , Antihipertensivos/efectos adversos , China/epidemiología , Estudios Transversales , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Madres , Medicamentos sin Prescripción/efectos adversos , Embarazo , Medicamentos bajo Prescripción/efectos adversos , Factores de Riesgo
10.
Nat Prod Res ; 22(6): 554-63, 2008 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-18415865

RESUMEN

The characterization of an L-amino acid oxidase purified from Agkistrodon acutus snake venom was investigated. An L-amino acid oxidase (LAAO) was purified from A. acutus snake venom through DEAE Sepharose F.F. and Source 30 S chromatography. The molecular mass of this enzyme was determined by SDS-PAGE, size exclusion chromatography, and mass spectrometry. Substrate specificity, cytotoxicity, antitumor activity in vivo, and apoptosis-inducing activity were assayed. The LAAO purified from A. acutus snake venom was designated as ACTX-6. It is a covalently bound homodimer and its molecular mass is about 96 kDa. This enzyme preferred to oxidize hydrophobic L-amino acids; the best substrates were L-Met, L-Leu, L-Trp, and L-Phe. ACTX-6 demonstrated cytotoxicity in vitro and could inhibit tumor growth in vivo. Flow cytometry analysis showed that it could markedly increase accumulation of sub-G1 phase, which suggested that this enzyme could induce apoptosis. ACTX-6 could effectively inhibit tumor growth and it is a potential substance to develop into an antitumor drug.


Asunto(s)
Agkistrodon/metabolismo , Antineoplásicos/aislamiento & purificación , Venenos de Crotálidos/enzimología , L-Aminoácido Oxidasa/aislamiento & purificación , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Venenos de Crotálidos/química , Femenino , Citometría de Flujo , Humanos , L-Aminoácido Oxidasa/química , L-Aminoácido Oxidasa/farmacología , Masculino , Ratones , Peso Molecular , Neoplasias del Cuello Uterino/tratamiento farmacológico , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Neurogastroenterol Motil ; 29(11)2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28585346

RESUMEN

BACKGROUND: Tacr2 is one of the G protein-coupled receptors(GPCRs) that mediate the biological actions of tachykinins. It is abundantly expressed in the gastrointestinal (GI) system and is thought to play an important role in GI motility, secretion, and visceral sensitivity. Previously, the physiological and pathophysiological functions of Tacr2 were mainly studied using Tacr2 selective agonists or antagonists. Here, we seek to investigate the effect of Tacr2 disruption in mice to provide further insights. METHODS: The Tacr2 knockout mice were generated by homologous recombination and the phenotypic changes of the Tacr2-null mice were analyzed and compared with their wild type (wt) littermates. KEY RESULTS: Increased food retention was detected in Tacr2-/- mice. The stomach of Tacr2-/- mice had thinner muscularis externa and less neurons in the myenteric plexus. The stomach and small intestine exhibited longer duration of electrical field stimulation (EFS)-induced inhibition in the gastric fundus and decreased frequency of migrating motor complex (MMC), respectively. Neuronal nitric oxide synthase (nNOS) and vasoactive intestinal polypeptide (VIP) were significantly up-regulated due to Tarc2 deficiency, contributing to enhanced nitric oxide (NO) signaling in the stomach of Tacr2-/- mice. Intraperitoneal application of 7-nitroindazole (7-NI) to Tacr2-/- mice effectively relieved the gastric emptying disturbance. Moreover, Creb and NF-κB signalings were involved in the regulation of these physiological changes initiated by Tacr2 deficiency. CONCLUSIONS & INFERENCES: Tacr2 negatively regulated the expression of nNOS and VIP both in vivo and in vitro. Its ablation in mice elevated the expression of nNOS and VIP, enhanced NO signaling and changed the Creb and NF-κB signalings, finally leading to the gastric emptying disturbance of Tacr2-/- mice.


Asunto(s)
Vaciamiento Gástrico , Mucosa Gástrica/metabolismo , Receptores de Neuroquinina-2/fisiología , Estómago/fisiopatología , Animales , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Femenino , Fundus Gástrico/fisiopatología , Regulación de la Expresión Génica , Intestino Delgado/fisiopatología , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , FN-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo I/metabolismo , Fenotipo , Antro Pilórico/fisiopatología , Receptores de Neuroquinina-2/genética , Receptores de Neuroquinina-2/metabolismo , Transducción de Señal , Estómago/patología , Péptido Intestinal Vasoactivo/metabolismo
12.
Exp Gerontol ; 22(2): 113-25, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3622651

RESUMEN

We studied the effect of aging on the incorporation of 3H-arginine into vasopressin (VP) molecule in the hypothalamus (HT) and the rate of its transport into the neurohypophysis (NH) of male Fischer 344 rats of different ages: 2-3 months (young, n = 28), 11-13 months (adult, n = 30) and 30 months (old, n = 27). 3H-arginine was injected in a single dose through a permanent cannula into the lateral ventricle of an awake animal. The rats were decapitated 1, 6, and 24 h after the injection. VP was extracted from individual HTs and NHs (without pars intermedia), purified in a chromatography column and determined by RIA. Hypothalamus: One hour after the injection the 3H-activity was highest in the young, lower in the adult and lowest in the old rats, whereas the specific activity (cpm/pg VP) was similar in all age groups, reflecting endogenous VP content to be highest in the young, lower in the adult and lowest in the old rats. In the young rats both activities decreased 6 and 24 h after the injection. The adult rats also exhibited declining activities, whereas in the old rats the activities remained unchanged from 1 to 24 h after the injection. Neurohypophysis: One hour after the injection of radioactive label 3H-activity and specific activity were significantly lower in the NH of the old than in those of young and adult rats. The activities increased 6 h after the injection in all age groups with the lowest values in the old rats. After 6 h, both activities in the old rats reached only the 1-h values of the young and adult rats suggesting a delay of at least 6 h in the axonal transport of newly synthetized VP in aged rats. Twenty-four hours after the injection both activities increased in all age groups exhibiting no difference among the age groups, indicating a decreased release of the newly synthetized VP from the NH of aged rats. These data demonstrate an age-related decrease in the rate of incorporation of 3H-arginine into VP, in the rate of its axonal transport and in the release of newly synthetized VP from the NH of Fischer 344 rats.


Asunto(s)
Envejecimiento/metabolismo , Arginina Vasopresina/biosíntesis , Animales , Arginina/metabolismo , Arginina Vasopresina/metabolismo , Transporte Biológico Activo , Hipotálamo/metabolismo , Cinética , Masculino , Neurohipófisis/metabolismo , Ratas , Ratas Endogámicas F344
13.
Neuroreport ; 11(4): 697-700, 2000 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-10757503

RESUMEN

The present study investigated expression of beta-amyloid protein (AP) and Amyloid precursor protein (APP) in spinal motor neurons of young adult (3 month old) and aged (26-30 month old) rats. The total number of spinal motor neurons in the seventh cervical (C7) spinal segment was also examined in both young adult and aged rats. There was an approximately 21% (p<0.001) decrease in the number of motor neurons of the C7 spinal segment in aged rats compared with young ones. Immunoreactivity (IR) of AP and APP was not observed in spinal motor neurons of young adult rats. In contrast, approximately 50% of the spinal motor neurons of the aged rats were APP positive. Furthermore, extensive immunoreactivity was found in the processes of spinal motor neurons of aged rats. These results have shown that AP and APP is coincident with the loss of motor neurons in the spinal cord of aged rats, and might be associated with the degenerative processes of ageing motor neurons.


Asunto(s)
Péptidos beta-Amiloides/análisis , Supervivencia Celular/fisiología , Neuronas Motoras/metabolismo , Médula Espinal/metabolismo , Factores de Edad , Envejecimiento/metabolismo , Precursor de Proteína beta-Amiloide/análisis , Animales , Recuento de Células , Muerte Celular , Inmunohistoquímica , Masculino , Ratas , Ratas Sprague-Dawley
14.
Brain Res Bull ; 22(2): 399-410, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2706545

RESUMEN

Thirty-two Sprague-Dawley rats were divided into four groups, eight rats per group. Animals were hypophysectomized with removal of both the pars distalis and the neural lobe of the neurohypophysis. Groups of eight rats were euthanized 1, 2, 4 and 8 weeks following hypophysectomy and prepared for routine scanning electron microscopy (SEM) and correlative immunoelectron microscopy employing antisera against arginine vasopressin (AVP). Eight normal rats served as controls. In experimental rats that survived one to eight weeks posthypophysectomy, remarkable neuroanatomical alterations were notable in the median eminence and adjacent third cerebral ventricular lumen. In contrast to normal control rats, large numbers of neurites were observed with SEM to insinuate from the lateral recess into the cerebral ventricular lumen and as early as one week following hypophysectomy they overgrew the apical surfaces of ependymal cells that constitute the lining of the cerebral ventricle. Immunoelectron microscopy revealed that a significant proportion of these neurites were magnocellular in origin in that they harbored AVP-positive neurosecretory vesicles. In addition to large numbers of invading magnocellular neurites, neuronal perikayria with apparent axosomatic synapses were observed to emerge upon the thick feltwork of invading axons, the latter of which appeared to freely terminate within the ventricular lumen. AVP-positive axon profiles were, in addition, seen to terminate upon the basal lamina of portal perivascular spaces in the zona externa of the median eminence. These data are consistent with the idea that following hypophysectomy (to include high stalk section of the neurohypophyseal system), that there is rapid, and dynamic sprouting and regrowth of AVP-positive axons into the adjacent third cerebral ventricular lumen and to the contact zone of the median eminence as well. This phenomenon may represent a compensatory physiological response to injury of the neurohypophyseal system characterized by a highly plastic neuroanatomical reorganization of magnocellular elements which appear to utilize the CSF of the third cerebral ventricle as a functional terminus for the neurocisternal secretion of AVP which ultimately enters the systemic circulation.


Asunto(s)
Arginina Vasopresina/metabolismo , Hipofisectomía , Eminencia Media/fisiología , Plasticidad Neuronal , Animales , Inmunohistoquímica , Eminencia Media/metabolismo , Eminencia Media/ultraestructura , Microscopía Electrónica de Rastreo , Ratas , Ratas Endogámicas
15.
Life Sci ; 41(12): 1473-9, 1987 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-3626767

RESUMEN

Isoproterenol (1 mg/kg) was subcutaneously injected into adult male rats during the day to stimulate pineal N-acetyltransferase (NAT) activity and pineal and serum melatonin levels. Two hours after isoproterenol administration when levels of each of these variables had increased significantly, the experimental animals swam for 10 min in 22 degrees C water. At 15 min after swimming onset, pineal and serum melatonin levels were highly significantly depressed compared to those in control animals that did not swim. The high NAT level was not influenced by swimming. In a second study, isoproterenol injected rats swam for either 1, 3, 6 or 10 min and were sampled 15 min after the onset of swimming. The reduction in the elevated pineal melatonin in these animals was correlated with the length of the swim, i.e., as the duration of swim increased the percent reduction in pineal melatonin also increased. Neither pineal NAT nor hydroxyindole-O-methyltransferase (HIOMT) activities were influenced by swimming. The results suggest that elevated pineal and serum melatonin induced by isoproterenol can be depressed with no effect on the activity of the enzymes which convert serotonin to melatonin.


Asunto(s)
Isoproterenol/farmacología , Melatonina/análisis , Glándula Pineal/análisis , Estrés Fisiológico/metabolismo , Animales , Arilamina N-Acetiltransferasa/análisis , Masculino , Ratas , Ratas Endogámicas , Natación , Factores de Tiempo
16.
Biotechnol Prog ; 17(4): 778-80, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11485443

RESUMEN

For an industrial fermentation system, design of a suitable medium for cultivation of cells is an important step. Medium selection is commonly carried out with a lot of experimental works. In the present study, a simple method was proposed for medium selection in cultivation of Bacillus thuringiensis for production of thuringiensin. A droplet of medium was employed to test the suitability of the medium.


Asunto(s)
Bacillus thuringiensis/crecimiento & desarrollo , Medios de Cultivo , Técnicas Microbiológicas
17.
Biotechnol Prog ; 8(5): 465-8, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1369228

RESUMEN

Gas-liquid mass transfer in an airlift reactor with net draft tube is investigated. The effects of both the ratio of draft tube to reactor diameter and the reactor pressure on oxygen transfer are considered. The value of the volumetric mass transfer coefficient, kLa, increases with a decreasing diameter ratio at higher air flow rates. The correlation of volumetric mass transfer coefficient with respect to the true superficial air velocity under different reactor pressures is determined. The kLa value decreases with increasing reactor pressure.


Asunto(s)
Biotecnología/métodos , Fermentación , Oxígeno/farmacocinética , Biotecnología/instrumentación , Presión
18.
Mutat Res ; 409(1): 37-48, 1998 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-9806501

RESUMEN

The repair of UV-induced DNA damage in the phosphoenolpyruvate carboxykinase (PEPCK) gene was studied in primary cultures of hepatocytes isolated from young (6-month-old) and old (24-month-old) rats fed ad libitum and old rats fed a calorie-restricted diet. Incubation of the hepatocytes with cAMP rapidly induced PEPCK transcription and mRNA levels 4- to 5-fold. In absence of cAMP, the repair of the PEPCK fragment was similar in cultured hepatocytes isolated from young and old rats fed ad libitum. However, cAMP significantly increased the percentage of cyclobutane pyrimidine dimers (CPDs) removed from the PEPCK fragment 12 h after UV-irradiation in cultured hepatocytes isolated from young rats fed ad libitum. This increase was due to an increase in the repair of the transcribed strand of the PEPCK fragment. In contrast, cAMP did not increase the repair of the PEPCK fragment in cultured hepatocytes isolated from old rats fed ad libitum in spite of an increase in PEPCK transcription. Thus, it appears that the coupling of transcription and DNA repair is compromised in cultured hepatocytes isolated from old rats fed ad libitum. However, cultured hepatocytes isolated from old rats fed a calorie-restricted diet showed an induction in the rate of repair of the transcribed strand of the PEPCK fragment by cAMP that was similar to hepatocytes isolated from young rats fed ad libitum.


Asunto(s)
AMP Cíclico/análogos & derivados , Reparación del ADN/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Fosfoenolpiruvato Carboxiquinasa (GTP)/genética , Tionucleótidos/farmacología , Transcripción Genética/efectos de los fármacos , Envejecimiento/genética , Envejecimiento/metabolismo , Animales , Separación Celular , AMP Cíclico/farmacología , ADN/genética , ADN/metabolismo , ADN/efectos de la radiación , Daño del ADN , Reparación del ADN/genética , Dieta , Expresión Génica/efectos de los fármacos , Técnicas In Vitro , Hígado/citología , Masculino , Ratas , Ratas Endogámicas F344 , Mapeo Restrictivo
19.
Ann Acad Med Singap ; 21(2): 176-89, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1519881

RESUMEN

Fifteen Oriental noses were examined macrosurgically and microscopically. Five soft tissue layers overlying the osseocartilaginous framework are identified: the skin, the subcutaneous areolar plane, the vascular-fibromuscular layer, the deep areolar plane and perichondrium/periosteum. Two natural planes of dissection are represented by these areolar planes which separate the nose into an overlying skin envelope, a vascular-fibromuscular layer and an underlying osseocartilaginous framework. The cartilaginous framework provides projection, support and shape to the dorsum and tip of the nose but not to the alar lobule as this is devoid of cartilage. As there is no cartilage in the Alar lobule, the term 'Alar Cartilage' is misleading and the term 'Tip Cartilage' is introduced to replace it. The skin of the nose is specialised and has the ability to retain its shape even after dissection. This is due to an arrangement of elastin fibres in the upper dermis and the subcutaneous areolar plane which confers elasticity to the skin especially in the region of the Alar lobule which is a skin and fibromuscular sandwich. The vascular fibromuscular layer is like a sheet draping the osseocartilaginous framework. The main arteries of the nose lie on this layer. Injection studies of the blood supply reveal many arterial variations but always a distinct alar artery, columellar artery and alar plexus that have not been previously named. The alar groove is a junction between the alar lobule which is soft tissue alone and the tip which is soft tissue, supported by cartilage. The alar groove lies over the lateral edge of the tip cartilage and here there is muscular attachment to the fibromuscular layer.


Asunto(s)
Pueblo Asiatico , Nariz/anatomía & histología , Antropometría , Cartílago/anatomía & histología , China/etnología , Disección , Estudios de Evaluación como Asunto , Músculos Faciales/anatomía & histología , Humanos , Masculino , Nariz/irrigación sanguínea , Valores de Referencia , Singapur , Piel/anatomía & histología
20.
Ann Acad Med Singap ; 21(5): 640-8, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1292393

RESUMEN

A bank explosion in a neighbouring country over 1000 km away resulted in ten badly burned victims being airlifted to the Burns Centre, Singapore General Hospital (BCSGH) for treatment. The severely injured included patients with 90%, 80%, 74%, 66%, 45%, 33% and 31% burns. Nine had respiratory burns (four severe, one moderate, four mild). One patient died, thus, the mortality rate for the six most severely injured was 16.7%. This differs from predicted mortality rates of 78% according to McCoy or 54% according to Thompson, Herndon et al. The factors contributing to this result were the small size of the disaster, the use of an established Burns Mass Disaster plan and an individual management policy that incorporates carefully monitored fluid resuscitation, recognition of respiratory burns with early treatment by intubation thus pre emptying complications, early surgery and a multidisciplinary approach to complications such as infection and renal failure. The average length of stay was 43 days (range 5-122 days). The cost of the hospitalisation of the ten casualties was $312,317.00.


Asunto(s)
Traumatismos por Explosión/terapia , Quemaduras por Inhalación/terapia , Explosiones , Adulto , Unidades de Quemados/organización & administración , Planificación en Desastres , Servicios Médicos de Urgencia , Femenino , Humanos , Malasia , Persona de Mediana Edad , Grupo de Atención al Paciente , Singapur , Transporte de Pacientes
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