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1.
Zhonghua Yu Fang Yi Xue Za Zhi ; 52(2): 175-179, 2018 Feb 06.
Artigo em Chinês | MEDLINE | ID: mdl-29429273

RESUMO

Objective: This study aimed to investigate the influence of monobutyl phthalate (MBP) on the expressions of epithelial-mesenchymal transition (EMT)-related proteins, migration and invasion of mouse Leydig tumor cells (MLTC-1) cells. Methods: After exposed to different doses of MBP (0、10(-7)、10(-6), 10(-5), 10(-4), 10(-3) mol/L) for 24 h or 48 h, cell viability was determined by 3-(4 5-dimethyl-2-thiazolyl)-2 5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Expressions of vimentin, E-cadherin, N-cadherin and Snail proteins related to EMT were detected by Western blot. The ability of migration and invasion of MLTC-1 were assessed by wound healing assay and Transwell Boyden chamber assay, respectively. Results: Relative expressions of vimentin, Snail and N-cadherin proteins were promoted ((1.56±0.07) vs (1.78±0.08), (1.22±0.06) vs (1.44±0.07), (1.33±0.11) vs (2.19±0.06), all P values were<0.001) and E-cadherin (0.66±0.09) vs (0.47±0.06), P<0.001,protein was inhibited after the cells stimulated with MBP (0, 10(-7) and 10(-6) mol/L). The capability of wound closure of MLTC-1 cells were (6.64±2.07)%, (15.61±2.83)%, (39.91±0.33)%, respectively and the invading/migrating cells were (32.67±3.51), (57.67±2.52), (82.67±6.51), respectively, which were obviously increased under MBP treatments (0, 10(-7) and 10(-6) mol/L) (all P values were <0.001). Conclusion: Monobutyl phthalate affected the expressions of EMT-related proteins and enhanced the migration and invasion of MLTC-1 cells.


Assuntos
Transição Epitelial-Mesenquimal , Tumor de Células de Leydig , Ácidos Ftálicos/farmacologia , Animais , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular , Expressão Gênica/efeitos dos fármacos , Camundongos
2.
Int J Obes (Lond) ; 40(3): 417-24, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26447738

RESUMO

BACKGROUND/OBJECTIVES: Cannabinoid receptor 1 (CB1) is the best-characterized cannabinoid receptor, and CB1 antagonists are used in clinical trials to treat obesity. Because of the wide range of CB1 functions, the side effects of CB1 antagonists pose serious concerns. G-protein-coupled receptor 55 (GPR55) is an atypical cannabinoid receptor, and its pharmacology and functions are distinct from CB1. GPR55 regulates neuropathic pain, gut, bone, immune functions and motor coordination. GPR55 is expressed in various brain regions and peripheral tissues. However, the roles of GPR55 in energy and glucose homeostasis are unknown. Here we have investigated the roles of GPR55 in energy balance and insulin sensitivity using GPR55-null mice (GPR55(-/-)). METHODS: Body composition of the mice was measured by EchoMRI. Food intake, feeding behavior, energy expenditure and physical activity of GPR55(-/-) mice were determined by indirect calorimetry. Muscle function was assessed by forced treadmill running test. Insulin sensitivity was evaluated by glucose and insulin tolerance tests. Adipose inflammation was assessed by flow cytometry analysis of adipose tissue macrophages. The expression of inflammatory markers in adipose tissues and orexigenic/anorexigenic peptides in the hypothalamus was also analyzed by real-time PCR. RESULTS: GPR55(-/-) mice had normal total energy intake and feeding pattern (i.e., no changes in meal size, meal number or feeding frequency). Intriguingly, whereas adult GPR55(-/-) mice only showed a modest increase in overall body weight, they exhibited significantly increased fat mass and insulin resistance. The spontaneous locomotor activity of GPR55(-/-) mice was dramatically decreased, whereas resting metabolic rate and non-shivering thermogenesis were unchanged. Moreover, GPR55(-/-) mice exhibited significantly decreased voluntary physical activity, showing reduced running distance on the running wheels, whereas muscle function appeared to be normal. CONCLUSIONS: GPR55 has an important role in energy homeostasis. GPR55 ablation increases adiposity and insulin resistance by selectively decreasing physical activity, but not by altering feeding behavior as CB1.


Assuntos
Obesidade/patologia , Receptores de Canabinoides/fisiologia , Animais , Composição Corporal , Modelos Animais de Doenças , Ingestão de Alimentos , Metabolismo Energético , Deleção de Genes , Regulação da Expressão Gênica , Homeostase , Camundongos , Camundongos Knockout , Condicionamento Físico Animal , Receptores de Canabinoides/metabolismo
4.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(7): 1080-1085, 2023 Jul 10.
Artigo em Chinês | MEDLINE | ID: mdl-37482710

RESUMO

Objective: To characterize the incidence density of systematic lupus erythematosus (SLE) in Yinzhou District of Ningbo from 2016 to 2021, and compare the age and gender specific differences. Methods: A retrospective cohort study was conducted based on the related data from 2015 to 2021 collected from the Health Information Platform of Yinzhou. Suspected SLE cases in local residents were identified by fuzzy matching of International Classification of Diseases 10th edition code "M32" or Chinese text "lupus". The classification criteria from Systemic Lupus International Collaboration Clinics-2012 and The European League Against Rheumatism/American College of Rheumatology-2019 were used for case verification. SLE cases were identified with specific algorithm based on verification results, and new cases were identified with 1 year as the washout period. The incidence density and 95%CI were estimated by Poisson distribution. Results: From 2016 to 2021, a total of 1 551 921 permanent residents were registered in Yinzhou, in whom 51.52% were women. The M(Q1,Q3) age at enrollment was 40.38 (27.54, 53.54) years. The M(Q1,Q3) of follow-up person-years was 3.83 (0.41, 5.83) years. There were 451 new SLE cases, in which 352 were women (78.05%). The 6-year incidence density was 8.14/100 000 person-years (95%CI: 7.41/100 000 person-years-8.93/100 000 person-years) for the total population, 3.68/100 000 person-years (95%CI: 2.99/100 000 person-years-4.48/100 000 person-years) for men and 12.37/100 000 person-years (95%CI: 11.11/100 000 person-years- 13.73/100 000 person-years) for women. The incidence density in men appeared a small peak at 20-29 years old, and began to increase with age from 40 years old. The incidence density in women was highest in age group 20-29 years (16.57/100 000 person-years) and remained to be high until 30-79 years old. The incidence density of SLE in Yinzhou show no significant temporal trend from 2016 to 2021 (men: P=0.848; women: P=1.000). Conclusions: The incidence density of SLE in Yinzhou from 2016 to 2021 was similar to those of other areas in China. SLE has a high incidence in women, especially in the young and elderly, suggesting that more attention should be paid to the diagnosis and treatment of SLE in women.


Assuntos
Lúpus Eritematoso Sistêmico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Povo Asiático , Incidência , Lúpus Eritematoso Sistêmico/epidemiologia , Lúpus Eritematoso Sistêmico/diagnóstico , Estudos Retrospectivos , China/epidemiologia
5.
Front Oncol ; 10: 1476, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33014786

RESUMO

Background: Accurate evaluation of local invasion (T-stage) of rectal cancer is essential for treatment planning. A search of PubMed database indicated that the correlation between texture features from T2-weighted magnetic resonance imaging (T2WI) (MRI) and T-stage has not been explored extensively. Purpose: To evaluate the performance of texture analysis using sagittal fat-suppression combined with transverse T2WI for determining T-stage of rectal cancer. Methods: One hundred and seventy-four rectal cancer cases who underwent preoperative MRI were retrospectively selected and divided into high (T3/4) and low (T1/2) T-stage groups. Texture features were, respectively, extracted from sagittal fat-suppression and transverse T2WI images. Univariate and multivariate analyses were conducted to determine T-stage. Discrimination performance was assessed by receiver operating characteristic (ROC) analysis. Results: For univariate analysis, the best performance in differentiating T1/2 from T3/4 tumors was achieved from transverse T2WI, and the area under the ROC curve (AUC) was 0.740. For multivariate analysis, the logical regression model incorporating the independent predictors achieved an AUC of 0.789. Conclusions: Texture features from sagittal fat-suppression combined with transverse T2WI presented moderate association with T-stage of rectal cancer. These findings may be valuable in selecting optimum treatment strategy.

6.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(12): 2029-2033, 2020 Dec 10.
Artigo em Chinês | MEDLINE | ID: mdl-32397698

RESUMO

Objective: To investigate a cluster epidemic of COVID-19 after a mass gathering activity in Ningbo of Zhejiang province and analyze the transmission chain and status of infection cases of different generations. Methods: The tracking of all the close contacts of the first COVID-19 case and epidemiological investigation were conducted on January 29, 2020 after a cluster epidemic of COVID-19 related with a Buddhism rally on January 19 (the 1.19 rally) in Ningbo occurred. The swabs of nose/throat of the cases and close contacts were collected and tested for nucleic acids by real-time fluorescence quantitative RT-PCR. Results: From January 26 to February 20, 2020, a total of 67 COVID-19 cases and 15 asymptomatic infection cases related with the 1.19 rally were reported in Ningbo. The initial case was the infection source who infected 29 second generation cases and 4 asymptomatic infection cases, in whom 23 second generation cases and 3 asymptomatic infection cases once took bus with the initial case, the attack rate was 33.82% (23/68) and the infection rate was 38.24% (26/68). The risks of suffering from COVID-19 and being infected were 28.91 times and 26.01 times higher in rally participants taking bus with initial case compared with those taking no bus with initial case. In this epidemic, 37 third+generation cases and 11 related asymptomatic infection cases occurred, the attack rate was 2.88% (37/1 283) and the infection rate was 4.76% (48/1 008). The main transmission routes included vehicle sharing and family transmission. Conclusion: It was a cluster epidemic of COVID-19 caused by a super spreader in a massive rally. The epidemic has been under effective control.


Assuntos
COVID-19 , Epidemias , COVID-19/epidemiologia , China/epidemiologia , Humanos , Incidência , SARS-CoV-2
7.
Neuron ; 32(4): 619-34, 2001 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-11719203

RESUMO

The regulation of NMDA receptor (NMDAR) subunit composition and expression during development is thought to control the process of thalamocortical afferent innervation, segregation, and plasticity. Thalamocortical synaptic plasticity in the mouse is dependent on NMDARs containing the NR2B subunit, which are the dominant form during the "critical period" window for plasticity. Near the end of the critical period there is a gradual increase in the contribution of NR2A subunits that happens in parallel to changes in NMDAR-mediated current kinetics. However, no extension of the critical period occurs in NR2A knockout mice, despite the fact that NMDA subunit composition and current kinetics remain immature past the end of the critical period. These data suggest that regulation of NMDAR subunit composition is not essential for closing the critical period plasticity window in mouse somatosensory barrel cortex.


Assuntos
Período Crítico Psicológico , Plasticidade Neuronal/fisiologia , Receptores de N-Metil-D-Aspartato/genética , Córtex Somatossensorial/crescimento & desenvolvimento , Córtex Somatossensorial/fisiologia , Animais , Mapeamento Encefálico , Antagonistas de Aminoácidos Excitatórios/farmacologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Potenciação de Longa Duração/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Piperidinas/farmacologia , Quinoxalinas/farmacologia , Receptores de AMPA/genética , Receptores de AMPA/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapses/fisiologia , Tálamo/crescimento & desenvolvimento , Tálamo/fisiologia
8.
Hum Exp Toxicol ; 36(12): 1236-1247, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28067064

RESUMO

OBJECTIVE: To investigate the effects of in utero exposure to high-dose di- n-butyl phthalate (DBP) on testicular cell apoptosis in late embryonic and pubertal male rat offspring. METHODS: Twenty pregnant Sprague-Dawley (SD) rats were divided into two groups. During gestation day (GD) 12 to GD 19, control group was given 1 ml day-1 of olive oil and experimental group was given DBP 500 mg kg-1 day-1 by gavage. On GD 19.5 and postnatal day (PND) 45, the testes were removed. Morphological analysis of the testes was observed by transmission electron microscopy and hematoxylin and eosin (H&E) staining. Testicular cell apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL). The expression of Bcl-2, Bax, and p53 was presented by immunohistochemistry (IHC) and western blot. Data of the two groups was compared using independent samples t-test and Mann-Whitney test by SPSS 20.0. RESULTS: H&E staining showed that spermatogenetic cells were significantly decreased in DBP exposed pubertal rat testis. The apoptosis index of testes in DBP-treated group was significantly lower on GD 19.5 but higher on PND 45 than that of the controls ( p < 0.01). IHC and western blot revealed significantly increased expression of Bcl-2 in GD 19.5 rat testis and Bax and p53 in PND 45 rat testis after DBP exposure, compared with the control ( p < 0.05). CONCLUSION: In utero exposure of high-dose DBP resulted in opposite effects on testicular cell apoptosis in late embryonic and pubertal rat offspring. The overexpression of Bcl-2, Bax, and p53 might be related to the occurrence of abnormal apoptosis and finally produce male infertility.


Assuntos
Apoptose/efeitos dos fármacos , Dibutilftalato/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Testículo/citologia , Animais , Células Cultivadas , Criptorquidismo/induzido quimicamente , Dibutilftalato/administração & dosagem , Transtornos do Desenvolvimento Sexual/induzido quimicamente , Relação Dose-Resposta a Droga , Embrião de Mamíferos/citologia , Embrião de Mamíferos/efeitos dos fármacos , Feminino , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley
9.
Eur Rev Med Pharmacol Sci ; 20(16): 3378-84, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27608896

RESUMO

OBJECTIVE: Glioma is the most lethal form of cancer that originates mostly from the brain and less frequently from the spine. Glioma is characterized by abnormal regulation of glial cell differentiation. The severity of the glioma was found to be relaxed in isocitrate dehydrogenase 1 (IDH1) mutant. The present study focused on histological discrimination and regulation of cancer stem cell between IDH1 mutant and in non-IDH1 mutant glioma tissue. PATIENTS AND METHODS: Histology, immunohistochemistry and Western blotting techniques are used to analyze the glioma nature and variation in glioma stem cells that differ between IDH1 mutant and in non-IDH1 mutant glioma tissue. RESULTS: The aggressive form of non-IDH1 mutant glioma shows abnormal cellular histological variation with prominent larger nucleus along with abnormal clustering of cells. The longer survival form of IDH1 mutant glioma has a control over glioma stem cell proliferation. Immunohistochemistry with stem cell markers, CD133 and EGFRvIII are used to demonstrate that the IDH1 mutant glioma shows limited dependence on cancer stem cells and it shows marked apoptotic signals in TUNEL assay to regulate abnormal cells. The non-IDH1 mutant glioma failed to regulate misbehaving cells and it promotes cancer stem cell proliferation. CONCLUSIONS: Our finding supports that the IDH1 mutant glioma has a regulatory role in glioma stem cells and their survival.


Assuntos
Glioma/genética , Isocitrato Desidrogenase , Neoplasias Encefálicas , Proliferação de Células , Glioma/patologia , Humanos , Proteínas Mutantes , Mutação , Células-Tronco Neoplásicas
10.
Diabetes Care ; 19(12): 1449-50, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8941483

RESUMO

OBJECTIVE: To emphasize the continued incidence of phenformin-associated lactic acidosis. CASE REPORT: We report a case of phenformin-associated lactic acidosis in a Chinese man who received phenformin while in China. Diagnosis was made; the patient was treated appropriately and survived. COMMENTS: Phenformin-associated lactic acidosis may still occur in the U.S.


Assuntos
Acidose Láctica/induzido quimicamente , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/efeitos adversos , Fenformin/efeitos adversos , Acidose Láctica/terapia , Idoso , Glicemia/análise , China/etnologia , Hidratação , Humanos , Masculino , Panax , Plantas Medicinais , Respiração Artificial , Estados Unidos
11.
J Cereb Blood Flow Metab ; 2(2): 173-8, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7076729

RESUMO

We have studied the effect of brain tissue (gray matter-white matter) heterogeneity and computerized tomography (CT) noise on the accuracy of xenon CT measurements of regional cerebral blood flow (rCBF) based upon "autoradiographic" and multiple-scan washin protocols. The results of our mathematical analysis indicate that both protocols are associated with a variety of measurement errors that lead to unacceptable and, to a large extent, unpredictable uncertainties in calculated values of rCBF. Brain tissue heterogeneity and high volumetric flow rates may--even in the absence of movement artifact and CT noise--lead to measurement errors in excess of 20%. Moreover, CT noise is additive in regard to these errors, and constitutes the most confounding variable of all.


Assuntos
Circulação Cerebrovascular , Tomografia Computadorizada por Raios X , Xenônio , Animais , Autorradiografia , Encéfalo/anatomia & histologia , Eletricidade , Humanos , Modelos Biológicos
12.
J Cereb Blood Flow Metab ; 2(4): 408-14, 1982 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7142304

RESUMO

Computer simulations were done as a feasibility study of xenon computed tomographic measurements of regional cerebral blood flow. Accuracy of initial least squares estimates of gray matter and white matter rate constants from a two-compartment model depended very little on the number and timing of scans, but did depend significantly on the enhancement-to-noise ratio as well as on the true values of the rate constants and gray/white ratio. Nonlinear least squares gives an optimal fit of the predicted wash-in--wash-out curve to the data rather than optimal estimates of the rate constants. A polynomial correction factor was obtained by regressing initial estimates on the true values used to generate the simulations. The correction factor substantially reduced error in the estimates and, in particular, eliminated large outliers.


Assuntos
Circulação Cerebrovascular , Computadores , Modelos Biológicos , Encéfalo/diagnóstico por imagem , Humanos , Matemática , Fluxo Sanguíneo Regional , Tomografia Computadorizada por Raios X , Radioisótopos de Xenônio
13.
Neurology ; 50(4): 1149-52, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9566413

RESUMO

We investigated cytokine levels (interleukin [IL]-1beta, IL-1ra, IL-2, IL-6, tumor necrosis factor [TNF]-alpha, TNF-beta) in plasma and secreted by mitogen-stimulated blood monocytes and lymphocytes; T-cell subsets; and natural killer cell activity in patients with narcolepsy and in human leukocyte antigen (HLA)-DR2 matched controls. The only significant finding was higher IL-6 secretion by monocytes of patients than by those of the HLA-DR2-positive controls. In conclusion, we found no major abnormalities of T-cell function in patients with narcolepsy, but slight alterations of monocyte function deserving further investigation.


Assuntos
Antígeno HLA-DR2/análise , Narcolepsia/imunologia , Subpopulações de Linfócitos T/imunologia , Adulto , Feminino , Teste de Histocompatibilidade , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-1/metabolismo , Interleucina-2/metabolismo , Interleucina-6/metabolismo , Linfotoxina-alfa/metabolismo , Masculino , Pessoa de Meia-Idade , Sialoglicoproteínas/metabolismo , Sono REM/imunologia , Subpopulações de Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
14.
Arch Pediatr Adolesc Med ; 152(8): 803-5, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9701142

RESUMO

OBJECTIVES: To see if methemoglobin could potentially be misdiagnosed and the limitation of present cooximeters. PATIENT: A 17-year-old girl who overingested a combination of cimetidine, acetaminophen, ibuprofen, and naproxen in a suicide attempt. METHOD: Use of pulse co-oximeters to aid in the diagnosis of suspected sulfhemoglobinemia. RESULTS: Diagnosis of sulfhemoglobinemia achieved with final confirmation made with gas chromatography. Patient steadily improved with supportive care. CONCLUSIONS: There is a potential for the diagnosis of methemoglobin with some of the limitations of present co-oximeters. The laboratory diagnosis of sulfhemoglobinemia can be difficult to make.


Assuntos
Metemoglobinemia/diagnóstico , Sulfemoglobinemia/diagnóstico , Acetaminofen/intoxicação , Adolescente , Cimetidina/intoxicação , Diagnóstico Diferencial , Feminino , Humanos , Ibuprofeno/intoxicação , Naproxeno/intoxicação , Oximetria , Tentativa de Suicídio , Sulfemoglobinemia/induzido quimicamente
15.
Med Phys ; 11(5): 686-9, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6503885

RESUMO

A systematic increase in computed tomography (CT) number of approximately 0.13 Hounsfield unit per scan (HU/scan) was observed when serial DeltaScan 2020 CT scans of a uniform water phantom were equally spaced at 0.5, 1.0, or 2.0 min and a shaped aluminum beam-hardening filter was employed. Much smaller drifts (less than 0.06 HU/scan) were observed with flat aluminum or shaped beryllium oxide filters. This machine drift, which was not associated with a rise in water phantom temperature and did not consistently correlate with estimated x-ray tube heat, could result in a significant overestimation of regional cerebral blood flow (rCBF) for a xenon/CT rCBF protocol involving 5-7 sequential scans obtained at 1-min interscan intervals.


Assuntos
Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular , Tomografia Computadorizada por Raios X , Xenônio , Humanos , Modelos Estruturais
16.
Biotechnol Prog ; 16(1): 116-24, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10662499

RESUMO

A hydrophilic matrix of periodate-oxidized dextran was used as a double-sided linker to covalently immobilize Staphylococcus aureus protein A (SpA) molecules onto a poly-L-lysine-modified piezoelectric crystal surface to improve their stability, activity, and binding specificity with human immunoglobulin G (IgG) in flow injection assays. The prepared sensing crystals displayed best sensitivity and reusability at a flow rate of 140 microL/min. A human IgG concentration as low as 0.3 nM can be detected by this system. Up to 19 successive assay repetitions were achieved without significant loss of sensitivity using the same crystal. The analysis of adsorption kinetics indicates that such a preparation can greatly increase the amount of available active human IgG binding sites on immobilized SpA. Hardly any response arising from unspecific binding was detected. In addition, the sensing crystal prepared by this method was found to retain activity better than one prepared via direct deposition when stored in either wet or dry states. Finally, the prepared SpA-coated crystals were applied to the affinity immobilization of polyclonal goat anti-Schistosoma japonicum glutathione-S-transferase (GST) and were able to subsequently detect GST and its genetically engineered mutant either in a purified form or in the crude cell lysate.


Assuntos
Técnicas Biossensoriais , Análise de Injeção de Fluxo/métodos , Imunoensaio/métodos , Proteína Estafilocócica A , Animais , Anticorpos Anti-Helmínticos , Biotecnologia , Reutilização de Equipamento , Escherichia coli/genética , Glutationa Transferase/análise , Glutationa Transferase/genética , Glutationa Transferase/imunologia , Humanos , Imunoglobulina G/análise , Técnicas de Imunoadsorção , Proteínas Recombinantes/análise , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Schistosoma japonicum/enzimologia , Schistosoma japonicum/genética , Schistosoma japonicum/imunologia
18.
Development ; 124(1): 195-203, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9006080

RESUMO

Retinoids regulate various aspects of vertebrate development through the action of two types of receptors, the retinoic acid receptors (RARs) and the retinoid-X-receptors (RXRs). Although RXRs bind 9-cis-retinoic acid (9cRA) with high affinity, in vitro experiments suggest that RXRs are for the most part not liganded, but serve as auxiliary factors forming heterodimers with liganded partner receptors such as RAR. Here we have used RXR- and RAR-specific ligands 4-[1-(3,5,5,8,8-pentamethyl-5,6,7,8-tetrahydro-2-napthyl)ethenyl]b enzoic acid (LG69) and (E)-4-[2-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-2-naphthalenyl)-1-prope nyl]benzoic acid (TTNPB), and show that, in the context of an embryo, liganded RXR can mediate retinoid signal transduction. This conclusion emerges from examining the induction of several retinoid-responsive genes in the limb bud (Hoxb-6/-8, RARbeta) and in the developing central nervous system (Hoxb-1, otx-2). RARbeta and Hoxb-1 genes were most effectively activated by a combination of TTNPB and LG69, suggesting that the activation of these genes benefits from the presence of ligand-bound RAR and ligand-bound RXR. Hoxb-6/-8 genes were most efficiently induced by LG69, suggesting that liganded RXR can activate these genes. The regulation of the expression of the otx-2 gene was complex; expression was repressed by TTNPB, but such repression was relieved when LG69 was provided together with TTNPB, suggesting that ligand-bound RXR can overcome repression of transcription exerted by liganded RAR. Based on these findings, we propose that in our experimental system in which ligands are provided exogenously, transcriptional regulation of several genes involves liganded RXR.


Assuntos
Benzoatos/farmacologia , Regulação da Expressão Gênica no Desenvolvimento , Botões de Extremidades/fisiologia , Receptores do Ácido Retinoico/fisiologia , Retinoides/farmacologia , Transdução de Sinais , Tetra-Hidronaftalenos/farmacologia , Fatores de Transcrição/fisiologia , Animais , Benzoatos/metabolismo , Bexaroteno , Sistema Nervoso Central/embriologia , Embrião de Galinha , Indução Embrionária , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Genes Homeobox , Proteínas de Homeodomínio/biossíntese , Hibridização In Situ , Ligantes , Morfogênese , Proteínas do Tecido Nervoso/biossíntese , Fatores de Transcrição Otx , Receptores do Ácido Retinoico/biossíntese , Receptores X de Retinoides , Retinoides/metabolismo , Tetra-Hidronaftalenos/metabolismo , Transativadores/biossíntese
19.
Clin Infect Dis ; 33(10): 1621-7, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11595977

RESUMO

Early detection of fungal infections in and corresponding early treatment of febrile patients with neutropenia and cancer have been important issues and continue to be major challenges for clinicians. The use of nested PCR to make therapeutic decisions was studied. Sequential blood samples obtained from 42 patients with neutropenia and cancer were tested by nested PCR and culture. Instead of the empirical antifungal therapy strategy, amphotericin B treatment was initiated only for patients who had 2 consecutive positive results by nested PCR. A reduced mortality rate was observed for febrile patients with neutropenia and cancer who had fungal infections. Thus, this strategy, combined with the nested PCR for early detection of fungal infection in febrile patients with neutropenia, may be used as a guideline for antifungal therapy.


Assuntos
Antifúngicos/uso terapêutico , Febre/etiologia , Fungos/isolamento & purificação , Micoses/tratamento farmacológico , Neoplasias/complicações , Neutropenia/complicações , Reação em Cadeia da Polimerase/métodos , Adolescente , Sangue/microbiologia , Meios de Cultura , DNA Fúngico/análise , Fungemia/tratamento farmacológico , Fungemia/fisiopatologia , Fungos/genética , Humanos , Micoses/complicações , Micoses/fisiopatologia , RNA Ribossômico 18S/genética , Sensibilidade e Especificidade , Resultado do Tratamento
20.
Development ; 124(9): 1643-51, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9165113

RESUMO

We show that retinoid receptor antagonists applied to the presumptive wing region block the formation of a zone of polarizing activity (ZPA). This suggests a direct relationship between retinoid signaling and the establishment of the ZPA. We provide evidence that the Hox gene, Hoxb-8, is a direct target of retinoid signaling since exogenously applied RA rapidly induces this gene in the absence of protein synthesis and, moreover, retinoid receptor antagonists down-regulate Hoxb-8 expression. In addition, we find that, in the lateral plate mesoderm, the domains of Hoxb-8 expression and of polarizing activity are coextensive. Taken together, these findings support the hypothesis that retinoids are required for the establishment of a ZPA, and that retinoids act, at least in part, through Hoxb-8, a gene associated with ZPA formation (Charité et al., 1994).


Assuntos
Proteínas do Ovo/biossíntese , Proteínas de Homeodomínio/biossíntese , Glicoproteínas de Membrana/biossíntese , Mesoderma/fisiologia , Receptores do Ácido Retinoico/fisiologia , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/fisiologia , Tretinoína/farmacologia , Sequência de Aminoácidos , Animais , Benzoatos/farmacologia , Células Cultivadas , Embrião de Galinha , Galinhas , Cromanos/farmacologia , Indução Embrionária , Expressão Gênica , Proteínas de Homeodomínio/química , Botões de Extremidades/transplante , Mesoderma/efeitos dos fármacos , Camundongos , Dados de Sequência Molecular , Receptores de Superfície Celular/biossíntese , Receptores do Ácido Retinoico/antagonistas & inibidores , Receptores X de Retinoides , Retinoides/farmacologia , Homologia de Sequência de Aminoácidos , Tetra-Hidronaftalenos/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Asas de Animais/embriologia , Glicoproteínas da Zona Pelúcida
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