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1.
J Endocrinol Invest ; 47(8): 1839-1850, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38568373

RESUMEN

BACKGROUND AND PURPOSE: Asprosin was discovered as a new endocrine hormone originating from fibrillin-1 cleavage that plays a crucial role in various metabolic-related diseases, such as obesity, nonalcoholic fatty liver disease (NAFLD), diabetes, polycystic ovary syndrome (PCOS), and cardiovascular diseases. The purpose of this review is to describe the recent advancements of asprosin. METHOD: Narrative review. RESULT: This comprehensive review explores its tissue-specific functions, focusing on white adipose tissue, liver, hypothalamus, testis, ovary, heart, pancreas, skeletal muscle, and kidney. CONCLUSION: Asprosin is a multifaceted protein with tissue-specific roles in various physiological and pathological processes. Further research is needed to fully understand the mechanisms and potential of asprosin as a therapeutic target. These insights could provide new directions for treatments targeting metabolic-related diseases.


Asunto(s)
Fibrilina-1 , Enfermedades Metabólicas , Humanos , Fibrilina-1/metabolismo , Enfermedades Metabólicas/metabolismo , Animales , Proteínas de la Matriz Extracelular/metabolismo , Adipoquinas
2.
Clin Radiol ; 78(11): e847-e855, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37607844

RESUMEN

AIM: To explore the value of radiomics analysis in preoperatively predicting visceral pleural invasion (VPI) of lung adenocarcinoma (LAC) with ≤3 cm maximum diameter and to compare the performance of two-dimensional (2D) and three-dimensional (3D) computed tomography (CT) radiomics models. MATERIALS AND METHODS: A total of 391 LAC patients were enrolled retrospectively, of whom 142 were VPI (+) and 249 were VPI (-). Radiomics features were extracted from 2D and 3D regions of interest (ROIs) of tumours in CT images. 2D and 3D radiomics models were developed combining the optimal radiomics features by using the logistic regression machine-learning method and radiomics scores (rad-scores) were calculated. Nomograms were constructed by integrating independent risk factors and rad-scores. The performance of each model was evaluated by using the receiver operator characteristic (ROC) curve, decision curve analysis (DCA), clinical impact curve (CIC), and calculating the area under the curve (AUC). RESULTS: There was no difference in the VPI prediction between 2D and 3D radiomics models (training group: 2D AUC=0.835, 3D AUC=0.836, p=0.896; validation group: 2D AUC=0.803, 3D AUC=0.794, p=0.567). The 2D and 3D nomograms performed similarly regarding discrimination (training group: 2D AUC=0.867, 3D AUC=0.862, p=0.409, validation group: 2D AUC=0.835, 3D AUC=0.827, p=0.558), and outperformed their corresponding radiomics models and the clinical model. DCA and CIC revealed that the 2D nomogram had slightly better clinical utility. CONCLUSION: The 2D radiomics model has a similar discrimination capability compared with the 3D radiomics model. The 2D nomogram performs slightly better for individual VPI prediction in LAC.

3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(5): 583-589, 2022 May 06.
Artículo en Zh | MEDLINE | ID: mdl-35644971

RESUMEN

Objective: To explore the role of parental reproductive age on the risk of overweight and obesity in offspring. Methods: The participants were derived from physical examination data of students aged 6-18 years in seven provinces in China, and questionnaire survey was used to collect demographic characteristics and lifestyle information of the students and their parents. A total of 41 567 children with complete data were included. According to the restricted cubic spline curve, maternal reproductive age was divided into three categories, 14-23, 24-28, and 29-38 years, and paternal reproductive age was divided into 14-23, 24-30, and 31-42 years. Multivariate logistic regression model was used to analyze the association between parental reproductive age and parental nutritional status and the risk of overweight and obesity in offspring. Results: The mean age of 41 567 children was (10.6±3.2) years, and the mean paternal and maternal age were (27.9±4.4) years and (25.8±4.0) years, respectively. The detection rate of overweight and obesity was 23.4%. After adjusting factors of children diet and behaviors, the OR(95%CI)of offspring overweight and obesity in groups of fathers aged 24-30 years and mothers aged 24-28 years was 1.11 (1.04-1.18) and 1.16 (1.08-1.24), respectively. When none parents were overweight and obese, the difference of obesity risk was not statistically significant. When both parents were overweight and obese, the OR(95%CI)of offspring overweight and obesity in groups of fathers aged 24-30 years and mothers aged 14-28 years old was 1.27 (1.00-1.62) and 1.33 (1.07-1.65) respectively. Conclusion: Parental reproductive age and parental overweight and obesity status may both increase the risk of overweight and obesity in offspring, with a significant interaction effect.


Asunto(s)
Obesidad , Sobrepeso , Adolescente , Adulto , Niño , Padre , Femenino , Humanos , Masculino , Madres , Obesidad/epidemiología , Sobrepeso/epidemiología , Factores de Riesgo , Adulto Joven
4.
J Endocrinol Invest ; 44(8): 1753-1765, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33423221

RESUMEN

PURPOSE: Evidence is accumulating that lipocalin2 (LCN2) is implicated in insulin resistance and glucose homeostasis, but the underlying possible mechanisms remain unclear. This study is to investigate the possible linkage between LCN2 and AMP-activated protein kinase (AMPK) or forkhead transcription factor O1 (FoxO1), which influences insulin sensitivity and gluconeogenesis in liver. METHODS: LCN2 knockout (LCN2KO) mice and wild-type littermates were used to evaluate the effect of LCN2 on insulin sensitivity and hepatic gluconeogenesis through pyruvate tolerance test (PTT), glucose tolerance test (ipGTT), insulin tolerance test (ITT), and hyperinsulinemic-euglycemic clamps, respectively. LCN2KO mice and WT mice in vivo, and in vitro HepG2 cells were co-transfected with adenoviral FoxO1-siRNA (Ad-FoxO1-siRNA) or adenovirus expressing constitutively active form of AMPK (Ad-CA-AMPK), or dominant negative adenovirus AMPK (Ad-DN-AMPK), the relative mRNA and protein levels of two key gluconeogenic enzymes phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6P) were measured. RESULTS: Improved insulin sensitivity and inhibited gluconeogenesis in the LCN2KO mice were confirmed by pyruvate tolerance tests and hyperinsulinemic-euglycemic clamps. Nuclear FoxO1 and its downstream genes PEECK and G6P were decreased in the livers of the LCN2KO mice, and AMPK activity was stimulated and directly phosphorylated FoxO1. In vitro, AMPK activity was inhibited in HepG2 cells overexpressing LCN2 leading to a decrease in phosphorylated FoxO1 and an increase in nuclear FoxO1. CONCLUSION: The present study demonstrates that LCN2 regulates insulin sensitivity and glucose metabolism through inhibiting AMPK activity, and regulating FoxO1 and its downstream genes PEPCK/G6P, which regulate hepatic gluconeogenesis.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Proteína Forkhead Box O1/metabolismo , Gluconeogénesis/fisiología , Lipocalina 2/genética , Hígado/metabolismo , Animales , Glucosa/metabolismo , Células Hep G2 , Humanos , Resistencia a la Insulina , Lipocalina 2/metabolismo , Ratones , Ratones Noqueados , Fosforilación
5.
Zhonghua Xin Xue Guan Bing Za Zhi ; 49(9): 873-879, 2021 Sep 24.
Artículo en Zh | MEDLINE | ID: mdl-34530594

RESUMEN

Objective: This analysis was performed to evaluate the efficacy and the safety of rivaroxaban-aspirin combination therapy in secondary prevention of major adverse cardiovascular events in Chinese patients enrolled in the COMPASS trial. Methods: COMPASS was a prospective, international multi-center and randomized controlled trial. From September 2014 to February 2017, 1 086 patients with stable coronary artery disease and peripheral artery diseases were recruited from 31 centers in China. Patients were randomly assigned to separately receive the therapy of rivaroxaban (2.5 mg twice a day) plus aspirin (100 mg once a day,) group (n=366), rivaroxaban (5 mg twice a day) alone group (n=365), and aspirin (100 mg once a day) alone group (n=355). Baseline information such as age, sex, etc. of all three groups was collected. Finally, 1 081 patients were followed up successfully, with the follow-up rate 99.5% and the average follow-up time was 19 months. The primary efficacy endpoint was the composite of cardiovascular death, myocardial infarction and stroke. The primary safety endpoint was major bleeding evaluated by modified International Society on Thrombosis and Haemostasis criteria. Results: Age of patients was (64.2±8.3) years and there were 293 male in rivaroxaban plus aspirin group. Age of patients was (63.8±9.0) years, and there were 301 male patients in rivaroxaban alone group. Age of patients was (63.6±8.8) years, and there were 282 male patients in the aspirin alone group. The incidences of primary efficacy endpoint occurred in 9 cases (1.5%) in rivaroxaban with aspirin group, 21 cases (3.7%) in rivaroxaban alone group and 14 cases (2.5%) in aspirin alone group. Meanwhile, the incidences of primary safety endpoint occurred in 6 cases (1.0%) in rivaroxaban with aspirin group, 9 cases (1.6%) in rivaroxaban alone group and 7 cases (1.2%) in aspirin alone group. The net clinical benefit events were 10 cases (1.7%) in rivaroxaban with aspirin group, 22 cases (3.9%) in rivaroxaban alone group and 15 cases (2.7%) in aspirin alone group (P>0.5%). Conclusions: The combination of rivaroxaban with aspirin can be safe and effectively used for the secondary prevention in Chinese patients with stable coronary artery disease and peripheral artery diseases.


Asunto(s)
Enfermedades Cardiovasculares , Rivaroxabán , Anciano , Aspirina/uso terapéutico , Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedades Cardiovasculares/prevención & control , China , Quimioterapia Combinada , Inhibidores del Factor Xa/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/uso terapéutico , Estudios Prospectivos , Rivaroxabán/uso terapéutico , Prevención Secundaria
6.
Zhonghua Bing Li Xue Za Zhi ; 49(7): 710-714, 2020 Jul 08.
Artículo en Zh | MEDLINE | ID: mdl-32610383

RESUMEN

Objective: To investigate the clinicopathologic and immunophenotypic features of metastatic gastrointestinal hepatoid adenocarcinomas in the liver. Methods: Eight cases of hepatic metastatic gastrointestinal hepatoid adenocarcinoma diagnosed at the Affiliated Drum Tower Hospital, Nanjing University Medical School from January 2009 to January 2019 were retrospectively analyzed. The clinical data, histopathologic features and immunohistochemical (IHC) characteristics performed by EnVision method were analyzed. Results: There were five males and three females with a mean age of 66 years. The primary sites included one case each from the distal esophagus and the right colon, and the other six cases were from the stomach. Pre-treatment serum AFP levels were increased in four patients, normal in two, and was not known in two other patients. Liver metastases occurred in all eight patients at initial diagnosis. Microscopically, the primary tumor was composed of areas showing hepatic differentiation with or without typical adenocarcinoma component; and the areas with hepatic differentiation morphologically resembled hepatocellular carcinoma (HCC). IHC staining showed variable expression of HCC markers such as Glypican 3, AFP, SALL4 and HepPar-1, and gastrointestinal adenocarcinoma markers such as CK19, CDX-2 and Villin in both the primary and metastatic foci of hepatoid adenocarcinoma. Conclusions: Hepatoid adenocarcinoma in the digestive tract gives rise to only non-specific symptoms, and shows high propensity for invasion and metastasis. When liver metastasis is the presenting symptom, it is difficult to distinguish metastatic hepatoid adenocarcinoma from the primary HCC based on histopathologic characteristics alone. The accurate diagnosis of metastatic hepatoid adenocarcinoma in the liver requires combination of clinical, radiologic, histopathologic and IHC findings.


Asunto(s)
Adenocarcinoma , Carcinoma Hepatocelular , Neoplasias Hepáticas , Anciano , Biomarcadores de Tumor , Femenino , Neoplasias Gastrointestinales , Humanos , Inmunohistoquímica , Masculino , Estudios Retrospectivos , alfa-Fetoproteínas
7.
Infect Dis Poverty ; 10(1): 30, 2021 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-33731226

RESUMEN

The ongoing coronavirus disease 2019 (COVID-19) pandemic has put a strain on health systems globally. Although Africa is the least affected region to date, it has the weakest health systems and an exponential rise in cases as has been observed in other regions, is bound to overwhelm its health systems. Early detection and isolation of suspected and confirmed COVID-19 cases are pivotal to the prevention and control of the pandemic. The World Health Organization (WHO) recommends that all laboratory-confirmed cases should be isolated and treated in a health care facility; however, where this is not possible due to the health system capacity, patients can be isolated in re-purposed facilities or at home. An already very apparent future challenge for Africa is facility-based isolation of COVID-19 cases, given the already limited health infrastructure and health workforce, and the risk of nosocomial transmission. Use of repurposed facilities requires additional resources, including health workers. Home isolation, on the other hand, would be a challenge given the poor housing, overcrowding, inadequate access to water and sanitation, and stigma related to infectious disease that is prevalent in many African societies. Conflict settings on the continent pose an additional challenge to the prevention and control of COVID-19 with the resultant population displacements in overcrowded camps where access to social services is limited. These unique cultural, social, economic and developmental differences on the continent, call for a tailored approach to COVID-19 case management strategies. This article proposes three broad case management strategies based on the transmission scenarios defined by WHO, and the criteria and package of care for each option, for consideration by policy makers and governments in African countries. Moving forward, African countries should generate local evidence to guide the development of realistic home-grown strategies, protocol and equipment for the management of COVID-19 cases on the continent .


Asunto(s)
COVID-19/epidemiología , COVID-19/virología , Manejo de Caso , SARS-CoV-2 , África/epidemiología , Américas/epidemiología , Asia/epidemiología , COVID-19/diagnóstico , COVID-19/terapia , Atención a la Salud , Manejo de la Enfermedad , Europa (Continente)/epidemiología , Encuestas de Atención de la Salud , Humanos
8.
Braz J Biol ; 80(4): 790-797, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31800764

RESUMEN

Ginkgo biloba is a traditional Chinese herbal medicine containing multiple components that contribute to its notable bioactivities. Variations of seasonal, meteorological and planting soil on the phytochemicals contents in G. biloba leaves due to the effects of growth meteorological and soil parameters were investigated in this study. The leaves of G. biloba were collected from different months and place in Zhejiang province, the contents of flavones (quercetin, kaempferol and isorhamnetin) and terpene lactones (bilobalide, ginkgolides A, B and C) were quantified by high performance liquid chromatography (HPLC) and the evaporative light scattering detector (ELSD) method. The established methods were validated with good linearity, precision, repeatability, stability, and recovery. Comprehensive analysis suggested the proper harvest time for G. biloba was in October of Zhejiang province. The result of correlation analysis with meteorological factors shows that the temperature and precipitation have non-significant effect on the main components of G. biloba. In addition, the type and content (Mn and Zn) of the soil showed significantly effect on the content of flavonoids and terpene lactones. This study enriched the knowledge on the development and utilization value of the G. biloba leaves and was useful for determining the optimal harvest time and growing condition.


Asunto(s)
Ginkgo biloba , Suelo , Cromatografía Líquida de Alta Presión , Extractos Vegetales , Hojas de la Planta , Estaciones del Año
9.
Eur Rev Med Pharmacol Sci ; 22(5): 1358-1365, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29565494

RESUMEN

OBJECTIVE: We investigated the expression of human long non-coding ribonucleic acid (lncRNA), BRAF-activated non-coding RNA (BANCR) in breast cancer tissues and its effects on the in vitro proliferation, apoptosis, invasion and metastasis of breast cancer cells; also, we investigated its possible mechanism. PATIENTS AND METHODS: The expressions of BANCR in 65 pairs of breast cancer tissues and para-carcinoma normal breast tissues were detected by Real-time fluorescence quantitative polymerase chain reaction (qRT-PCR). The expressions of BANCR in normal breast epithelial cells (MCF10A) and breast cancer cells (MCF-7, MDA-MB-231, SKBR3 and BT-20) were further detected. The knockdown efficiency of BANCR small interfering RNA (siRNA) in MCF-7 cells was detected by qRT-PCR. The effects of BANCR knockdown on proliferation, apoptosis, invasion and metastasis capacities of MCF-7 cells were explored via methyl thiazolyl tetrazolium (MTT) proliferation assay, cell colony formation assay, fluorescence-activated cell sorting (FACS) and transwell migration assay. Western blotting was used to detect the changes in expressions of apoptosis-related proteins, epithelial-mesenchymal transition (EMT)-related proteins and matrix metalloproteinases (MMPs) after knockdown of BANCR. RESULTS: The expression level of lncRNA BANCR in breast cancer tissues was significantly higher than that in para-carcinoma normal tissues. The prognosis of patients in low-expression BANCR group was significantly superior to that of patients in high-expression BANCR group. After BANCR knockdown in breast cancer MCF-7 cells, the cell proliferation and colony formation capacities were significantly inhibited. Further mechanism research showed that inhibiting BANCR could promote the apoptosis of MCF-7 cells. Results of Western blotting revealed that the expressions of B-cell lymphoma 2 associated X protein (BAX), cleaved-Caspase-3 and cleaved-poly adenosine diphosphate-ribose polymerase (PARP) in knockdown group were significantly up-regulated compared with those in control group. Both wound-healing assay and transwell migration assay showed that the down-regulation of lncRNA BANCR could inhibit the invasion and metastasis capacities of MCF-7 cells, whose mechanism was related to the inhibition of EMT process and down-regulation of MMP expressions in cells. CONCLUSIONS: LncRNA BANCR is highly expressed in breast cancer, which is significantly correlated with the prognosis of patients; moreover, it can promote the growth, invasion and metastasis of ovarian cancer cells. The down-regulation of BANCR can inhibit the proliferation, invasion and metastasis capacities of MCF-7 cells.


Asunto(s)
Neoplasias de la Mama/patología , Proliferación Celular , ARN Largo no Codificante/metabolismo , Apoptosis , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Línea Celular Tumoral , Movimiento Celular , Transición Epitelial-Mesenquimal , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Estimación de Kaplan-Meier , Metaloproteinasa 2 de la Matriz/metabolismo , Persona de Mediana Edad , Poli(ADP-Ribosa) Polimerasas/metabolismo , Pronóstico , Proteínas Proto-Oncogénicas B-raf/genética , Interferencia de ARN , ARN Largo no Codificante/antagonistas & inhibidores , ARN Largo no Codificante/genética , ARN Interferente Pequeño/metabolismo , Proteína X Asociada a bcl-2/metabolismo
10.
Braz. j. biol ; 80(4): 790-797, Oct.-Dec. 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1142527

RESUMEN

Abstract Ginkgo biloba is a traditional Chinese herbal medicine containing multiple components that contribute to its notable bioactivities. Variations of seasonal, meteorological and planting soil on the phytochemicals contents in G. biloba leaves due to the effects of growth meteorological and soil parameters were investigated in this study. The leaves of G. biloba were collected from different months and place in Zhejiang province, the contents of flavones (quercetin, kaempferol and isorhamnetin) and terpene lactones (bilobalide, ginkgolides A, B and C) were quantified by high performance liquid chromatography (HPLC) and the evaporative light scattering detector (ELSD) method. The established methods were validated with good linearity, precision, repeatability, stability, and recovery. Comprehensive analysis suggested the proper harvest time for G. biloba was in October of Zhejiang province. The result of correlation analysis with meteorological factors shows that the temperature and precipitation have non-significant effect on the main components of G. biloba. In addition, the type and content (Mn and Zn) of the soil showed significantly effect on the content of flavonoids and terpene lactones. This study enriched the knowledge on the development and utilization value of the G. biloba leaves and was useful for determining the optimal harvest time and growing condition.


Resumo Ginkgo biloba é um fitoterápico tradicional da medicina chinesa que contém vários componentes que contribuem para suas notáveis bioatividades. Variações sazonais, meteorológicos e de plantio do solo sobre os teores fitoquímicos em folhas de G. biloba, devido aos efeitos do crescimento meteorológico e parâmetros do solo, foram investigadas neste estudo. As folhas de G. biloba foram coletadas em diferentes meses e na província de Zhejiang, os teores de flavonas (quercetina, kaempferol e isorhamnetina) e lactonas terpênicas (bilobalida, ginkgolídeos A, B e C) foram quantificados por Cromatografia Líquida de Alta Eficiência (CLAE) e pelo método do detector de dispersão da luz por evaporação. Os métodos estabelecidos foram validados com boa linearidade, precisão, repetibilidade, estabilidade e recuperação. Uma análise abrangente sugeriu que o tempo de colheita adequado para G. biloba foi em outubro na província de Zhejiang. O resultado da análise de correlação com fatores meteorológicos mostra que a temperatura e a precipitação não têm efeito significativo sobre os principais componentes de G. biloba. Além disso, o tipo e composição (Mn e Zn) do solo apresentaram efeito significativo sobre o teor de flavonoides e lactonas terpênicas. Este estudo enriqueceu o conhecimento sobre o valor de desenvolvimento e utilização das folhas de G. biloba e foi útil para determinar o melhor tempo de colheita e condição de crescimento.


Asunto(s)
Suelo , Ginkgo biloba , Estaciones del Año , Extractos Vegetales , Cromatografía Líquida de Alta Presión , Hojas de la Planta
11.
J Immunol Methods ; 9(1): 69-79, 1975 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-812921

RESUMEN

Electroimmunoassay is a simple, rapid and accurate method for quantitating the serum proteins. By use of glutaraldehyde, intermolecular cross-linkage of immunoglobulins to albumin was effected. The conjugation resulted in increased electrophoretic mobility of the immunoglobulins without perceptible change in antigenic determinants. With a Tris-EDTA-boric acid buffer system, the cross-linked immunoglobulins migrated anodically in an electrical field. Six serum proteins from each of 20 samples were quantitated by electroimmunoassay, and the results correlated with values obtained by radial immunodiffusion.


Asunto(s)
Aldehídos , Proteínas Sanguíneas/análisis , Glutaral , Complemento C3/análisis , Conductividad Eléctrica , Humanos , Inmunoensayo/métodos , Inmunodifusión/métodos , Inmunoelectroforesis , Inmunoglobulina A/análisis , Inmunoglobulina G/análisis , Inmunoglobulina M/análisis , Transferrina/análisis , alfa 1-Antitripsina/análisis
12.
Mol Cell Endocrinol ; 90(2): 187-95, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8495800

RESUMEN

In Manduca sexta, basal and PTTH-stimulated secretion of ecdysteroids by prothoracic glands in vitro increases from days 1 to 4 of the fifth larval stage. Glandular content of cAMP-dependent protein kinase was analyzed to determine if the enzyme changes in concert with increased secretory response. Photoaffinity labeling with [32P]8-N3 cAMP revealed a 55-kDa cAMP-binding protein characteristic of the regulatory subunit of type-II cAMP-dependent protein kinase (RII). It appears that RII is one of a limited number of cellular proteins that is phosphorylated in the presence of [gamma-35S]ATP; the thiophosphorylated protein and the photoaffinity-labeled regulatory subunit possess the same M(r) and pI, and thiophosphorylation is blocked by mammalian cAMP-dependent protein kinase inhibitor. From days 1 to 4 of the fifth instar, glandular content of RII increases in conjunction with increased ecdysteroid secretory capacity. Application of JH analog on day 1 significantly inhibits the observed increase in RII. Catalytic subunit activity does not change from days 1 to 4 of the fifth instar, nor does cellular content of a 34-kDa protein previously shown to be phosphorylated in response to PTTH. While it is unlikely that increased content of RII is solely responsible for enhanced ecdysteroid secretion by the prothoracic glands, it may serve as a convenient marker for investigating the mechanism by which steroidogenic capacity is regulated.


Asunto(s)
Ecdisona/metabolismo , Mariposas Nocturnas/metabolismo , Proteínas Quinasas/biosíntesis , Animales , Ecdisteroides , Electroforesis en Gel de Poliacrilamida , Glándulas Endocrinas/enzimología , Glándulas Endocrinas/metabolismo , Técnicas In Vitro , Hormonas de Insectos/biosíntesis , Hormonas de Insectos/fisiología , Hormonas de Invertebrados/biosíntesis , Focalización Isoeléctrica , Larva/crecimiento & desarrollo , Larva/metabolismo , Mariposas Nocturnas/crecimiento & desarrollo , Neuropéptidos/fisiología , Fosforilación , Esteroides/biosíntesis
13.
Mol Cell Endocrinol ; 74(3): 229-37, 1990 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-1965648

RESUMEN

The involvement of protein and RNA synthesis in insect steroidogenesis was investigated using the prothoracic glands of the tobacco hornworm Manduca sexta. Ecdysone secretion stimulated by prothoracicotropic hormone (PTTH) and by cAMP analogs such as dibutyryl cAMP (dbcAMP), was suppressed by the translation inhibitors cycloheximide and puromycin, and by the transcription inhibitor actinomycin D. Inhibition of protein synthesis did not prevent the activation of glandular kinases, as indicated by continued protein phosphorylation in the presence of cycloheximide. Incorporation of radiolabeled amino acids and uridine increased within 60 min of glandular activation, suggesting that ecdysteroid secretion was accompanied by enhanced protein and RNA synthesis. One-dimensional gel electrophoresis revealed an increase in the translation of glandular proteins within 20 min of activation. The results suggest that the translation of protein from short-lived mRNA is necessary for optimal synthesis of ecdysteroids, and that the requisite proteins act beyond the activation of cAMP-dependent protein kinase.


Asunto(s)
Ecdisona/biosíntesis , Hormonas de Insectos/genética , Insectos/genética , Animales , Bucladesina/farmacología , Ecdisona/análisis , Hormonas de Insectos/biosíntesis , Hormonas de Insectos/farmacología , Biosíntesis de Proteínas/efectos de los fármacos , Transcripción Genética/efectos de los fármacos
14.
Insect Biochem Mol Biol ; 26(2): 161-70, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8882659

RESUMEN

Prothoracicotropic hormone (PTTH), a peptide produced by the insect brain, stimulates the prothoracic glands to secrete ecdysteroids. The big form of this peptide (25.5 kDa) has been postulated to act through cyclic AMP in larval Manduca sexta, but the role of the cyclic nucleotide in the action of PTTH in pupal glands has been less clear. Results of the present study indicate that PTTH-stimulated ecdysteroid secretion and protein phosphorylation by glands removed from pupal Manduca sexta are blocked by two inhibitors of cAMP-dependent protein kinase: Rp-cAMPS, an antagonist of cAMP binding to the regulatory subunit of the kinase, and H-89, an inhibitor of the catalytic subunit of the kinase. Further, PTTH stimulates significant accumulation of cAMP in pupal glands, although less than that previously seen in PTTH-stimulated larval glands. Cyclic AMP-dependent protein kinase is found in cytoplasmic and membrane-associated glandular subfractions, as measured by incorporation of [32P]8-N3cAMP into the regulatory subunit of the kinase. PTTH enhances cytoplasmic cAMP content and appears to increase the amount of cAMP bound to a cytoplasmic type II regulatory subunit of cAMP-dependent protein kinase. The results indicate that cAMP plays a requisite role in PTTH action in pupal glands, thus arguing in favor of a uniform mechanism of action for the peptide during Manduca development.


Asunto(s)
AMP Cíclico/metabolismo , Ganglios de Invertebrados/metabolismo , Hormonas de Insectos/metabolismo , Manduca/metabolismo , Animales , Ecdisona/metabolismo , Pupa , Transducción de Señal
15.
FEMS Microbiol Lett ; 188(1): 75-9, 2000 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-10867237

RESUMEN

Glucosyltransferases (GtfB/C/D) of Streptococcus mutans, a pathogen for human dental caries, synthesize water-insoluble glucan through the hydrolysis of sucrose. Genetic and biochemical approaches have identified several active sites of these enzymes, but no three-dimensional (3D) structural evidence is yet available to elucidate the subdomain arrangement and molecular mechanism of catalysis. Based on a combined sequence and secondary structure alignment against known crystal structures of segments from closely related proteins, we propose here the 3D model of an N-terminal domain essential for the sucrose binding and splitting in GtfB. A Tim-barrel of (alpha/beta)(8) structural characteristics is revealed and the structural correlation for two peptides is described.


Asunto(s)
Glucosiltransferasas/química , Glucosiltransferasas/genética , Streptococcus mutans/enzimología , Secuencia de Aminoácidos , Sitios de Unión , Dominio Catalítico , Glucosiltransferasas/metabolismo , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Conformación Proteica , Alineación de Secuencia , Streptococcus mutans/química , Sacarosa/metabolismo
16.
J Matern Fetal Neonatal Med ; 16(3): 167-70, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15590443

RESUMEN

OBJECTIVE: To compare cervical length measurements obtained by transvaginal two-dimensional (2D) and transvaginal three-dimensional (3D) ultrasound. STUDY DESIGN: Thirty-four consecutive women having transvaginal assessment of cervical length as part of an obstetric ultrasound examination consented to have a 3D ultrasound scan. The cervical lengths obtained by the two methods were compared by Student's t test and regression equations. RESULTS: The mean cervical 2D length was 35.7 +/- 1.4 (SE) mm and 3D length was 43.7 +/- 1.9 mm (difference 8.0 mm +/- 0.98, p < 0.001). In the 12 women with cervical length on 2D < 35 mm, there was a 7.5 +/- 1.7 (SE) mm difference (p = 0.007). In all but one woman the 3D length obtained was the same or longer than the 2D length. The longer the cervical length on 3D imaging, the greater the difference from the 2D length (p < 0.001). CONCLUSION: The longer 3D cervical measurements may reflect the inability to measure the cervix adequately with 2D imaging, owing to anatomical factors. This finding may be useful in improving the predictive value of transvaginal ultrasound in assessing the risk for preterm delivery.


Asunto(s)
Cuello del Útero/diagnóstico por imagen , Imagenología Tridimensional , Ultrasonografía Prenatal , Femenino , Humanos , Trabajo de Parto Prematuro/etiología , Valor Predictivo de las Pruebas , Embarazo , Medición de Riesgo
17.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 18(1): 28-31, 2001 Feb.
Artículo en Zh | MEDLINE | ID: mdl-11172638

RESUMEN

OBJECTIVE: To investigate the relationship between sperm anomalies and chromosomal aberrance and to further understand the pathological changes of anomalous spermatozoa. METHODS: Light and electronic (SEM or TEM) microscopes were used for morphological analysis. Fluorescence in situ hybridization(FISH) with chromosome X-, Y-specific probes were used for aneuploidy detection in sperms of the patient. RESULTS: Ninety eight point seven five per cent of the Papanicolaou stained sperms were observed to be abnormal; 100% of the sperm heads were abnormal, measured under oil objective (1000 times); 60.25% of the sperms had two or more tails (the maximum being eight tails). SEM and TEM demonstrated that the heads contained a large amount of cytoplasmic structure, the surfaces of heads were uneven, the nuclei were of much irregular shape; besides aberrance in quantity, anomalies occurred with centromeres, mitochondria and flagella in the tails. The results of FISH showed that the aneuploidy rate of sex chromosomes was 61.41% which was parallel to the rate of polytails. CONCLUSION: Even though the chromosomes in somatic cells are normal, the chromosomes in anomalous sperms may be abnormal.


Asunto(s)
Aberraciones Cromosómicas , Cromosomas Sexuales , Espermatozoides/anomalías , Adulto , Aneuploidia , Humanos , Masculino , Espermatozoides/ultraestructura
18.
Zhonghua Nei Ke Za Zhi ; 29(1): 29-31, 61, 1990 Jan.
Artículo en Zh | MEDLINE | ID: mdl-2205450

RESUMEN

HLA class I antigens on hepatocyte membrane were studied in liver biopsies from 46 patients with chronic hepatitis B virus infection by using immunoenzyme technique. The results revealed that the density of HLA class I antigens displayed on hepatocyte membrane in HBeAg positive carriers with minor hepatic inflammatory activity (the high replicative phase) was lower than that in patients with chronic active liver diseases (the low replicative phase) (P less than 0.005), but higher than that in patients with anti-HBe positivity and minor hepatic inflammatory activity (the nonreplicative phase) (P less than 0.05). In a follow-up of 21 HBeAg positive chronic HBV carriers, we found that five of the seven cases with high-density HLA class I antigens showed display of antigens on hepatocyte membrane, whereas only one of the 14 cases with lowdensity antigens were seroconverted from HBe antigen to antibody within one year. These findings suggest that the display on HLA class I antigens on hepatocyte membrane is enhanced and the cytotoxic T lymphacytes can recognize and lyze the infected hepatocytes.


Asunto(s)
Portador Sano/inmunología , Hepatitis B/inmunología , Hepatitis Crónica/inmunología , Antígenos de Histocompatibilidad Clase I/análisis , Adolescente , Adulto , Membrana Celular/análisis , Femenino , Antígenos e de la Hepatitis B/análisis , Humanos , Técnicas para Inmunoenzimas , Hígado/citología , Masculino
19.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 21(6): 433-6, 2001 Jun.
Artículo en Zh | MEDLINE | ID: mdl-12577439

RESUMEN

OBJECTIVE: To investigate the effect and mechanism of emodin on pancreatic repairing and remodeling in treating acute pancreatitis by analyzing the change of cytokine transforming growth factor beta 1(TGF beta 1) gene expression, DNA synthesis and protein content in pancreatic tissue. METHODS: Acute pancreatitis was induced in rats by intraperitoneal infusion of caerulein, treated or untreated by emodin. The animals were sacrificed at 6, 24, 48, 72 or 96 hrs after treatment separately. The mRNA expression of TGF beta 1, DNA synthesis and total protein content in pancreatic tissue were tested by reverse transcription-polymerase chain reaction (RT-PCR), 3H-thymidin method and Lowry's method respectively. RESULTS: Serum amylase level was decreased significantly after emodin treatment. TGF beta 1 mRNA expression was undetectable in the intact pancreas or in 6 hrs after pancreatitis induction in the non-treated group, but revealed at 24 hrs after and reached the peak at 72 hrs later. However, in the emodin treated group, TGF beta 1 mRNA expression was detected at 6 hrs after treatment, with a higher level in 24 hrs and 48 hrs as compared with the non-treated group, and reaching the peak at 48 hrs after treatment. Moreover, the DNA synthesis and total protein content in pancreatic tissue decreased significantly at 72 hrs and 48 hrs after induction respectively, but both parameters increased significantly in the emodin treated group 96 hrs after treatment. CONCLUSION: The mechanism of emodin in treating acute pancreatitis might be by way of enhancing cytokine TGF beta 1 gene expression, regulating cell growth and differentiation, stimulating the formation of extracellular matrix components, increasing DNA synthesis and protein content, and to take part in pancreatic repairing and remodeling.


Asunto(s)
Emodina/farmacología , Páncreas/metabolismo , Pancreatitis/metabolismo , Factor de Crecimiento Transformador beta/biosíntesis , Enfermedad Aguda , Animales , ADN/biosíntesis , Masculino , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Distribución Aleatoria , Ratas , Ratas Wistar , Factor de Crecimiento Transformador beta/genética
20.
Nat Cell Biol ; 14(10): 1089-98, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23000965

RESUMEN

Protein ubiquitylation has emerged as a key regulatory mechanism in DNA-damage signalling and repair pathways. We report a proteome-wide, site-specific survey of ubiquitylation changes after ultraviolet irradiation, identifying numerous upregulated and downregulated ubiquitylation sites on known components of DNA-damage signalling, as well as on proteins not previously implicated in this process. Our results uncover a critical role for PCNA-associated factor PAF15 (p15(PAF)/KIAA0101) ubiquitylation during DNA replication. During unperturbed S phase, chromatin-associated PAF15 is modified by double mono-ubiquitylation of Lys 15 and 24 templated through PCNA binding. Replication blocks trigger rapid, proteasome-dependent removal of Lys 15/24-ubiquitylated PAF15 from PCNA, facilitating bypass of replication-fork-blocking lesions by allowing recruitment of translesion DNA synthesis polymerase polη to mono-ubiquitylated PCNA at stalled replisomes. Our findings demonstrate widespread involvement of ubiquitin signalling in genotoxic-stress responses and identify a critical function for dynamic PAF15 ubiquitylation in safeguarding genome integrity when DNA replication is challenged.


Asunto(s)
Proteínas Portadoras/metabolismo , Daño del ADN/fisiología , Reparación del ADN/fisiología , Ubiquitinación , Rayos Ultravioleta/efectos adversos , Línea Celular , Replicación del ADN/fisiología , Proteínas de Unión al ADN , ADN Polimerasa Dirigida por ADN/metabolismo , Humanos , Lisina/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Fase S/fisiología , Transducción de Señal/fisiología
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