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1.
Biol Sport ; 33(4): 399-405, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28090145

RESUMO

Standing-posture 8-electrode bioelectrical impedance analysis is a fast and practical method for evaluating body composition in clinical settings, which can be used to estimate percentage body fat (BF%) and skeletal muscle mass in a subject's total body and body segments. In this study, dual-energy X-ray absorptiometry (DXA) was used as a reference method for validating the standing 8-electrode bioelectrical impedance analysis device BC-418 (BIA8, Tanita Corp., Tokyo, Japan). Forty-eight Taiwanese male wrestlers aged from 17.9 to 22.3 years volunteered to participate in this study. The lean soft tissue (LST) and BF% in the total body and body segments were measured in each subject by the BIA8 and DXA. The correlation coefficients between total body, arm, leg segments impedance index (BI, ht2/Z) and lean soft tissue mass measured from DXA were r = 0.902, 0.453, 0.885, respectively (p < 0.01). In addition, the total body and segmental LST estimated by the BIA8 were highly correlated with the DXA data (r = 0.936, 0.466, 0.886, p < 0.01). The estimation of total body and segmental BF% measured by BIA8 and DXA also showed a significant correlation (r > 0.820, p < 0.01). The estimated LST and BF% from BIA8 in the total body and body segments were highly correlated with the DXA results, which indicated that the standing-posture 8-electrode bioelectrical impedance analysis may be used to derive reference measures of LST and BF% in Taiwanese male wrestlers.

2.
Horm Metab Res ; 47(2): 125-32, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24867139

RESUMO

The klotho protein produced by the choroid plexus is known as a humoral factor in central nervous system. Many hormones affecting the baroreflex sensitivity have been introduced in the brain. However, role of klotho in the baroreflex sensitivity is still unknown. Recently, mutations in the klotho gene have been linked to cardiovascular diseases in both animals and human subjects. Also, silencing of brain klotho has been reported to enhance cold-induced elevation of blood pressure. Thus, we investigated the role of klotho in maintenance of central cardiovascular reflex sensitivity. Male Wistar Kyoto (WKY) rats and spontaneously hypertensive rats (SHRs) were used. Either klotho shRNA or scramble shRNA was also ICV-infused into the brains of WKY rats to investigate the role of klotho in brain. Recombinant klotho or rat IgG was infused into the cerebral paraventricle (ICV) of SHRs for further understanding the role of klotho in hypertension. The baroreflex sensitivity was detected using the challenge with a depressor dose of sodium nitroprusside (SNP, 50 µg/kg) or with a pressor dose of phenylephrine (PE, 8 µg/kg). We found that silencing of klotho expression in the brain decreased the baroreflex sensitivity in WKY rats. Also, modulation of the blood pressure for one week altered the cardiovascular homeostasis and resulted in an increased expression of klotho in medulla oblongata. Moreover, the baroreflex sensitivity was restored in SHRs that received recombinant klotho through ICV brain. Thus, klotho is involved in the maintenance of baroreflex sensitivity in the brain.


Assuntos
Barorreflexo/fisiologia , Glucuronidase/biossíntese , Bulbo/metabolismo , Animais , Inativação Gênica , Humanos , Proteínas Klotho , Masculino , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
3.
Horm Metab Res ; 46(1): 1-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23828126

RESUMO

Fibrosis is the final disorder of end-stage renal disease. Activation of fibroblast growth factor (FGF) 23-klotho axis could suppress renal fibrosis in mice. Also, a marked decrease of klotho expression was observed in the kidney of streptozotocin-induced diabetic rats (STZ rats). However, relation of FGF in renal fibrosis remained unclear. This study was aimed to screen the effect of hyperglycemia on FGF receptor (FGFR) and fibrosis in kidney of rats with diabetic nephropathy and investigate this potential mechanism in cultured Madin-Darby Canine Kidney (MDCK) epithelial cells. STZ rats were used to treat with insulin or phloridzin at the dose sufficient to correct hyperglycemia for understanding the changes of renal dysfunction. The cultured MDCK cells were also used to treat with high glucose, hydrogen peroxide, or tiron in addition to transfection of siRNA to silence the klotho. Both insulin and phloridzin reversed fibrosis and FGFR expressions in kidney of STZ rats. It was confirmed in high glucose-exposed MDCK cells. However, klotho failed to modify the level of FGFR in MDCK cells. Meanwhile, FGFR was restored by tiron in MDCK cells and in diabetic rats without changing blood glucose. In conclusion, interstitial fibrosis and decreased FGFR expression are observed in the kidney of diabetic rats. This change is reversed by tiron without the correction of blood glucose. Also, klotho has no effect on expression of FGFR. Thus, decrease of oxidative stress is useful for the recovery of FGFR expression and improvement of renal fibrosis in type-1 like diabetic rats.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Rim/metabolismo , Rim/patologia , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Sal Dissódico do Ácido 1,2-Di-Hidroxibenzeno-3,5 Dissulfônico/farmacologia , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/complicações , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Cães , Fator de Crescimento de Fibroblastos 23 , Fibrose , Glucuronidase/metabolismo , Hiperglicemia/complicações , Hiperglicemia/metabolismo , Hiperglicemia/patologia , Insulina/farmacologia , Rim/efeitos dos fármacos , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Proteínas Klotho , Células Madin Darby de Rim Canino , Masculino , Camundongos , Florizina/farmacologia , Ratos , Ratos Wistar , Superóxidos/metabolismo
4.
Dis Esophagus ; 25(1): 40-7, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21595776

RESUMO

Treatment strategy of esophageal cancer mainly depends on accurate staging. At present, no single ideal staging modality is superior to another in preoperative tumor-node-metastasis (TNM) staging of patients with esophageal cancer. We aimed to investigate the efficacy of endoscopic ultrasonography (EUS) and positron emission tomography-computed tomography (PET-CT) for staging of esophageal cancer. We retrospectively studied 118 consecutive patients with esophageal squamous cell carcinoma who underwent esophagectomy with or without neoadjuvant chemoradiotherapy (CRT) over a near 3-year period between January 2005 and November 2008 at a tertiary hospital in Taiwan. Patients were separated into two groups: without neoadjuvant CRT (group 1, n= 28) and with CRT (group 2, n= 90). Medical records of demographic data and reports of EUS and PET-CT of patients before surgery were reviewed. A database of clinical staging by EUS and PET-CT was compared with one of pathological staging. The accuracies of T staging by EUS in groups 1 and 2 were 85.2% and 34.9%. The accuracies of N staging by EUS in groups 1 and 2 were 55.6% and 39.8%. The accuracies of T and N staging by means of PET-CT scan were 100% and 54.5% in group 1, and were 69.4% and 86.1% in group 2, respectively. In group 2, 38 of 90 patients (42.2%) achieved pathologic complete remission. Among them, two of 34 (5.9%) and 12 of 17 (70.6%) patients were identified as tumor-free by post-CRT EUS and PET-CT, respectively. EUS is useful for initial staging of esophageal cancer. PET-CT is a more reliable modality for monitoring treatment response and restaging. Furthermore, the accuracy of PET-CT with regard to N staging is higher in patients who have undergone CRT than those who have not.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Endossonografia , Neoplasias Esofágicas/diagnóstico , Imagem Multimodal , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia Adjuvante , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/terapia , Esofagectomia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estudos Retrospectivos , Sensibilidade e Especificidade , Resultado do Tratamento
5.
Med Mycol ; 48(2): 328-34, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20141372

RESUMO

To study the demographic changes of yeasts causing invasive infections in Taiwan, especially with respect to species distribution and antifungal susceptibility, we analyzed isolates obtained from four sterile sites of patients in 19 hospitals in 2002 (155 strains) and again from the same hospitals in 2006 (208 strains). Blood was the most common source of the yeasts, accounting for 73.8% of the total isolates, followed by ascites (21.5%), cerebrospinal fluid (3%), and synovia (1.7%). Candida albicans was the most frequently recovered species (50.1% of the total), followed by Candida tropicalis (20.7%), Candida glabrata (11.6%), Candida parapsilosis (8.5%), Cryptococcus neoformans (3.9%), Candida krusei (0.8%), and nine other species (4.3%). There were one (0.3%) and seven (1.9%) isolates with minimum inhibitory concentrations (MICs) of amphotericin B > or =2 mg/l after 24 h and 48 h incubation, respectively. In addition, there were 15 (4.3%) and 31 (8.6%) isolates with MICs of fluconazole > or =64 mg/l under the same conditions. The MIC(90) value of amphotericin B was 1 mg/l. The MIC(90) values of fluconazole were 4 mg/l after 24 h incubation and 32 mg/l after 48 h incubation. Interestingly, MICs for fluconazole > or =64 mg/l after 24 h were significantly higher for isolates obtained in 2006 than those in 2002 after 24 h (7.1% vs. 0.7%, p =0.009) and 48 h (13.5% vs. 2%, p =0.0003) incubations. The demographic difference between these two surveys is mainly due to one species, C. tropicalis.


Assuntos
Anfotericina B/farmacologia , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Candidíase/microbiologia , Fluconazol/farmacologia , Antifúngicos/farmacologia , Candidíase/sangue , Candidíase/epidemiologia , Farmacorresistência Fúngica , Humanos , Testes de Sensibilidade Microbiana , Vigilância da População , Taiwan/epidemiologia
6.
Horm Metab Res ; 41(8): 605-11, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19440953

RESUMO

Bone morphogenetic protein-7 (BMP-7) expression is known to be protective for renal damage during diabetic nephropathy and disappears early during the progression of diabetic nephropathy. However, changes in expression of BMP-7 and BMP-7 type II receptor (BMP-RII) during kidney nephropathy response to high glucose-induced oxidative stress remain unclear. In this study, we used streptozotocin-induced diabetic rats with diabetic nephropathy and treated them with insulin, phloridzin, or antioxidant tiron. The insulin, phloridzin, or tiron treatment improved the renal function and decreased fibronectin expression in the streptozotocin-induced diabetic rats. Both insulin and phloridzin could reverse the attenuation effects of hyperglycemia on BMP-7 and BMP-RII expressions in the kidneys of streptozotocin-induced diabetic rats through the correction of hyperglycemia. However, the decrease of BMP-7 and BMP-RII expressions in kidney of streptozotocin-induced diabetic rats could be reversed by tiron through decreasing the high glucose-induced oxidative stress but not through changing the levels of glucose. We further confirmed the effect on reversing the BMP-7 and BMP-RII expressions through decreasing oxidative stress by tiron treatment in high glucose exposed mesangial cells. Thus, we suggest that a decrease in oxidative stress is responsible for the improvement of renal function and recovery of renal BMP-7 and BMP-RII expression in streptozotocin-induced diabetic rats.


Assuntos
Proteína Morfogenética Óssea 7/metabolismo , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismo , Diabetes Mellitus Tipo 1/complicações , Nefropatias Diabéticas/metabolismo , Regulação para Baixo , Rim/metabolismo , Animais , Proteína Morfogenética Óssea 7/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Nefropatias Diabéticas/genética , Modelos Animais de Doenças , Expressão Gênica , Humanos , Masculino , Ratos , Ratos Wistar
7.
Respir Med Case Rep ; 25: 267-269, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30364655

RESUMO

A 83 years old man was admitted to acute medical unit for mild asthma exacerbation. He also had atrial fibrillation and was on dabigatran. A mass on left upper chest wall was incidentally found. There were bruises over left posterolateral aspect of chest wall. Chest X-ray showed left pleural effusion. Diagnostic tap yielded blood-stained fluid. Computer tomography showed left lung herniation. Cardiothoracic surgery team unit was consulted. Reduction of lung herniation and patch repair of chest wall defect was done.

8.
Neoplasma ; 54(4): 342-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17822325

RESUMO

For hepatocellular carcinoma (HCC) patients after primary treatment, conventional anatomical imagings may not be reliable in detecting residual, recurrent or metastatic lesions. The aim of this retrospective study was to evaluate the usability of FDG PET in the follow-up of HCC patients after prior interventional treatments. The database consisted of 10 male and 2 female (age range, 46-82 years; mean age, 63.4 +/- 11.7 years) who had received primary HCC treatments and underwent FDG PET scans at the National Taiwan University Hospital. The accuracy of FDG PET detection was determined by the histopathological results or other clinical evidences afterwards. Of the 22 lesions, FDG PET studies were able to detect 8 (8/10, 80%) intrahepatic lesions and 8 (8/12, 66.7%) extrahepatic lesions. The lesion based detection rate of FDG PET is 72.7% (16/22). FDG PET was able to detect at least 1 lesion in 11 patients. The 6 false negative lesions in 6 patients include 2 intrahepatic lesions, 1 brain lesion, 1 sphenoid sinus lesion and 2 multiple subcentimeter pulmonary lesions. FDG PET scan is able to provide valuable auxiliary information for the follow up of HCC patients clinically suspicious of recurrence if their conventional image findings are not unambiguous.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Fluordesoxiglucose F18 , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/terapia , Ablação por Cateter , Etanol/administração & dosagem , Feminino , Fluordesoxiglucose F18/farmacocinética , Humanos , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/diagnóstico por imagem , Compostos Radiofarmacêuticos/farmacocinética , Estudos Retrospectivos , alfa-Fetoproteínas/metabolismo
9.
Cancer Res ; 54(16): 4405-11, 1994 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-8044789

RESUMO

Cell lines deficient in poly(ADP-ribose) synthesis due to enzyme deficiency (ADPRT54 and ADPRT351) or substrate deficiency (N2, N3, and N4) are resistant to topoisomerase II-directed agents, including etoposide (VP-16), N-[4-(9-acridinylamino)-3-methoxyphenyl]methanesulfonamide, and Adriamycin, relative to the effect of these agents on parental V79 Chinese hamster cells. Resistance is stable in the ADPRT54 and ADPRT351 cell lines, whereas resistance in the N2, N3, and N4 cell lines occurs when the cells are grown in nicotinamide-deficient medium to produce a state of NAD deficiency. However, sensitivity to VP-16 reverts to normal when cellular NAD levels return to control levels during growth in nicotinamide-containing complete medium. Poly(ADP-ribose) polymerase-deficient cell lines show constitutively increased levels of a protein at M(r) 78,000 on Coomassie blue-stained, sodium dodecyl sulfate-polyacrylamide gels that was subsequently confirmed with monoclonal antibodies to be M(r) 78,000 glucose-regulated stress protein (GRP78). Similarly, N2, N3, and N4 cells show induction of GRP78 under nicotinamide-deficient conditions. Induction of GRP78 is associated with elevated levels of GRP78 mRNA and appears to be regulated at the transcriptional level. When N3 cells with deficiency of poly(ADP-ribose) synthesis due to NAD deficiency are shifted to complete, nicotinamide-containing medium, they restore their NAD content, undergo a decrease in GRP78 levels, and regain sensitivity to VP-16. When V79 cells are shifted to nicotinamide-deficient medium they undergo a reduction in NAD content, followed by a progressive elevation in GRP78 levels, and they subsequently become increasingly resistant to VP-16. These studies demonstrate a clear association between deficiency of the NAD-poly(ADP-ribose) synthesis system, induction of GRP78 synthesis, and resistance to VP-16.


Assuntos
Etoposídeo/farmacologia , Proteínas de Choque Térmico/biossíntese , NAD/deficiência , Poli(ADP-Ribose) Polimerases/deficiência , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cricetinae , Cricetulus , Resistência a Medicamentos , Glucose/fisiologia , Proteínas de Choque Térmico/química , Peso Molecular , NAD/administração & dosagem , NAD/biossíntese , Poli(ADP-Ribose) Polimerases/biossíntese
10.
Cancer Res ; 55(4): 868-73, 1995 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-7850801

RESUMO

We have recently demonstrated that cell lines deficient in poly(ADP-ribose) synthesis due to deficiency in the enzyme poly(ADP-ribose) polymerase (PADPRP) or depletion of its substrate NAD+ overexpress GRP78. Furthermore, this overexpression of GRP78 is associated with the acquisition of resistance to topoisomerase II-directed drugs such as etoposide (VP-16); (S. Chatterjee et al., Cancer Res., 54: 4405-4411, 1994). Thus, our studies suggest that interference with NAD+-PADPRP metabolism could provide an important approach to (a) define pathways of GRP78 induction, (b) study the effect of GRP78 on other cellular processes, (c) elucidate the mechanism of GRP78-dependent resistance to topoisomerase II targeted drugs, and (d) modulate responses to chemotherapy in normal and tumor tissues. However, in the in vivo situation, it is impractical to interfere with NAD+-PADPRP metabolism by mutational inactivation of PADPRP or by depletion of its substrate NAD+. Therefore, we have examined several inhibitors of NAD+-PADPRP metabolism including 3-aminobenzamide, PD128763, and 6-aminonicotinamide for their ability to reproduce the results obtained with cell lines deficient in NAD+-PADPRP metabolism relative to the induction of GRP78 and subsequent development of resistance to VP-16. Our studies show that 6-aminoicotinamide treatment is highly effective in the induction of GRP78 and subsequent development of resistance to VP-16, whereas treatment with 3-aminobenzamide or PD128763 does not induce GRP78 and thus does not result in VP-16 resistance.


Assuntos
Proteínas de Transporte/biossíntese , Etoposídeo/farmacologia , Proteínas de Choque Térmico , Chaperonas Moleculares/biossíntese , Inibidores de Poli(ADP-Ribose) Polimerases , 6-Aminonicotinamida/efeitos adversos , Animais , Benzamidas/farmacologia , Proteínas de Transporte/metabolismo , Cricetinae , Cricetulus , Resistência a Medicamentos , Chaperona BiP do Retículo Endoplasmático , Etoposídeo/toxicidade , Isoquinolinas/farmacologia , Chaperonas Moleculares/metabolismo , NAD/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Síndrome de Abstinência a Substâncias/fisiopatologia , Transcrição Gênica/efeitos dos fármacos
11.
Clin Cancer Res ; 1(2): 223-34, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9815977

RESUMO

A two-color flow cytometric technique was developed to analyze poly(ADP-ribose) polymerase (PADPRP) in different individuals as a function of different physiological or pathological conditions and to establish the basis for determining whether enzyme deficiency may predispose to degenerative or malignant disorders. Peripheral blood granulocytes were devoid of enzyme activity, whereas mononuclear cells had variable amounts. PADPRP was highest in B cells, intermediate in T cells, and lowest in monocytes. This pattern of enzyme distribution and relative enzyme content of different types of cells was remarkably constant in normal subjects. In a series of 66 normal donors there was no significant biological variation in enzyme content as a function of age, race, or sex. The mean PADPRP values in peripheral blood mononuclear cells from 81 random patient samples obtained from an ambulatory oncology clinic did not differ significantly from normal subjects. However, groups of patients with breast cancer, lymphocytic malignancies, and esophageal cancer were observed to have below normal levels for peripheral blood mononuclear cell PADPRP.


Assuntos
Leucócitos/enzimologia , Neoplasias/enzimologia , Poli(ADP-Ribose) Polimerases/sangue , Adulto , Fatores Etários , Antígenos CD/imunologia , Linfócitos B/enzimologia , Neoplasias da Mama/sangue , Neoplasias da Mama/enzimologia , Criança , Neoplasias Esofágicas/sangue , Neoplasias Esofágicas/enzimologia , Feminino , Citometria de Fluxo , Granulócitos/enzimologia , Humanos , Leucócitos/imunologia , Linfoma/sangue , Linfoma/enzimologia , Masculino , Monócitos/enzimologia , Neoplasias/sangue , Valores de Referência , Análise de Regressão , Linfócitos T/enzimologia
12.
J Comp Neurol ; 323(4): 495-518, 1992 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-1430319

RESUMO

The connectivity of a region surrounding the established thalamic auditory nuclei, n. ovoidalis (Ov) and n. semilunaris parovoidalis (SPO), was explored in the ring dove by using the anterograde tracers, Phaseolus vulgaris leucoagglutinin (PHAL) and biocytin, and the retrograde tracer, fluorogold. The Ov-SPO surround received a projection from a cell group along the interface of the auditory midbrain and the n. intercollicularis, as revealed with PHAL and biocytin, and was composed of neurons exhibiting a common morphology. These features and the presence of overlapping projections from different portions of the Ov-SPO surround suggest that this region comprises a functionally discrete area, which we term the Ov shell. Single unit recording within the shell established the existence of acoustically responsive units. Both PHAL and fluorogold labeling revealed a robust projection from the Ov shell to the caudomedial hypothalamus. Major telencephalic projections of the shell terminated within the ventral paleostriatal complex, "end-zones" of the field L, the caudomedial hyperstriatum ventrale, and regions immediately dorsal and lateral to the auditory neostriatum. Except for a portion of the shell bordering medial ovoidalis, PHAL injections into the shell also labeled fibers within the caudolateral neostriatum and along the lateral neostriatal rim. The connectivity of the Ov shell suggests that this region may integrate auditory pathways with brain regions associated with endocrine mediated behavior. In addition, the shell may constitute a source of converging input to several levels of central auditory pathways.


Assuntos
Columbidae/fisiologia , Audição/fisiologia , Estilbamidinas , Núcleos Talâmicos/anatomia & histologia , Estimulação Acústica , Animais , Vias Auditivas/anatomia & histologia , Eletrofisiologia , Feminino , Corantes Fluorescentes , Histocitoquímica , Hipotálamo/anatomia & histologia , Hipotálamo/fisiologia , Lisina/análogos & derivados , Masculino , Fito-Hemaglutininas
13.
J Comp Neurol ; 379(2): 300-12, 1997 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-9050792

RESUMO

Studies in songbirds suggest that neurogenesis during the first few years of life is related to song learning. In this study, we examined whether postnatal neurogenesis occurs in a nonsongbird, the ring dove (Streptoplia risoria), and whether it persists to old age. Twenty-four hours after a single intramuscular injection of [3H]thymidine, labeled cells were present in the brains, particularly in the lateral wall of the lateral ventricle of juvenile (3-month and 8-month) and adult (1-year to 8-year) doves. Two months after multiple [3H]thymidine injections, there were fewer labeled cells in the ventricular zone (VZ), but many labeled cells with neuronal morphology in the parenchyma of the forebrain; labeled cells were confirmed as neurons by using neuron-specific markers, microtubule-associated protein-2 (MAP-2) and anti-neuronal nucleus (NeuN). In general, new neurons were distributed in the forebrain without clustering in any particular nucleus. During the first year of life, however, neostriatum caudale and hyperstriatum, the regions known to be essential for proper integration of sensory cues and reproductive behavior, contained more new neurons than any other brain regions. These neuronal additions showed an age-related decline; the first reduction coincided with the dove's attainment of adult physical size (about 3 months old) and the second occurred when the dove would normally attain reproductive fitness (about 1 year old). A low level of forebrain neurogenesis persisted up to 8 years of age (the oldest animals studied). These observations suggest that neurogenesis in adulthood is widespread among birds but that the biological significance of adult neurogenesis in the ring dove remains to be determined.


Assuntos
Envelhecimento/fisiologia , Aves/fisiologia , Neurônios/citologia , Telencéfalo/crescimento & desenvolvimento , Animais , Autorradiografia , Contagem de Células , Divisão Celular/fisiologia , Feminino , Masculino , Telencéfalo/citologia , Timidina , Trítio
14.
J Endocrinol ; 74(1): 37-45, 1977 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-406345

RESUMO

This work was carried out to determine whether gonadotrophin releasing hormone(s) (GnRH) plays a role in the courtship behaviour of female ring doves. In particular, it tests the hypothesis that a high dose of oestrogen suppresses the synergistic action of GnRH with oestrogen which is required to elicit courtship behaviour. The hypothesis was formulated to provide an explanation for a finding in a previous study that ovariectomized ring doves treated with a high dose of oestrogen, paradoxically, failed to show courtship behaviour. In the present study, treatment with synthetic LH releasing hormone (RH) enabled such birds to show typical female behaviour, thus supporting the hypothesis. This LH-RH effect was not apparently mediated by LH or progesterone since treatment with LH or progesterone failed to induce courtship behaviour. In addition, LH-RH can synergise with sub-threshold doses of oestrogen to induce both nest-soliciting and squatting behaviour. This portion of the LH-RH effect complements similar results reported for the rat. Finally, the results of thyrotrophin releasing hormone point to the specificity of LH-RH and the results of an anti-ovulation LH-RH analogue agree with the LH-RH effect.


Assuntos
Columbidae/fisiologia , Corte , Hormônio Liberador de Gonadotropina/fisiologia , Animais , Estradiol/farmacologia , Feminino , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Luteinizante/farmacologia , Progesterona/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Hormônio Liberador de Tireotropina/farmacologia
15.
J Endocrinol ; 89(1): 79-89, 1981 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6783721

RESUMO

Sexually mature ring doves (Streptopelia risoria) maintained from hatch on a photoperiod of 14 h light : 10 h darkness (14L : 10D) and kept in isolation were transferred to 8L : 16D. This treatment resulted in a partial regression of the ovaries and testes and a fall in the concentration of plasma LH but not of plasma FSH. After 2--3 months exposure to 8L : 16D, the gonads regrew to their original size: this regrowth was accompanied by a parallel increase in the concentration of plasma LH. The responsiveness of the pituitary gland to LH releasing hormone in both sexes after 5 weeks of exposure to 8L : 16D (when the gonads were partially regressed) was similar to the response observed after 15 weeks exposure to this lighting schedule (when the gonads had regrown). It was concluded that the spontaneous recovery of gonadal size in ring doves exposed to 8L : 16D is controlled by the hypothalamus and does not involve changes in the functional capacity of the pituitary gland or of the gonads.


Assuntos
Columbidae/fisiologia , Luz , Ovário/fisiologia , Testículo/fisiologia , Animais , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Luteinizante/sangue , Masculino , Tamanho do Órgão , Periodicidade , Hipófise/efeitos dos fármacos , Testículo/anatomia & histologia , Testosterona/sangue
16.
J Endocrinol ; 86(2): 251-61, 1980 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7191878

RESUMO

A cytoplasmic progestin receptor has been characterized in the brain of castrated ring doves using an in-vitro assay that measures the binding of a synthetic progestin, [3H]17 alpha,21-dimethyl-19-nor-pregna-4,9-diene-3,20-dione(promegestone; R5020). The affinity of the receptor was similar in both the hyperstriatum and the hypothalamus (Kd approximately equal to 4 X 10(-10) mol/l). Its concentration was higher in the anterior hypothalamus-preoptic area (63 +/- 4 fmol/mg (S.E.M.) protein) than in other brain regions (posterior hypothalamus, 33 +/- 5; hyperstriatum, 28 +/- 3; midbrain, 17 +/- 4 fmol/mg protein; n = 7). Progesterone and R5020 competed well for binding but oestradiol and 5 beta-dihydrotestosterone did not. Corticosterone and, to a lesser extent, testosterone and 5 alpha-dihydrotestosterone completed for binding but much higher concentrations were required than for progestins. Injections of testosterone (200 micrograms testosterone propionate daily for 7 days) significantly increased the concentration of progestin receptors in the anterior and posterior hypothalamus without having any significant effect on other brain areas. Shorter treatment, lasting for 2 days, with testosterone propionate (200 micrograms daily), 5 alpha-dihydrotestosterone (200 micrograms daily) or oestradiol benzoate (50 micrograms daily) did not always cause this increase but seven injections of oestradiol benzoate (50 micrograms daily for 7 days) were even more effective than seven injections of testosterone propionate (200 micrograms daily for 7 days). These data suggested that the sensitivity to progesterone of the brain of the bird changes as a consequence of increases in the level of testosterone in the circulation.


Assuntos
Encéfalo/metabolismo , Columbidae/metabolismo , Progestinas , Receptores de Progesterona/metabolismo , Animais , Ligação Competitiva , Encéfalo/efeitos dos fármacos , Castração , Citoplasma/metabolismo , Di-Hidrotestosterona/farmacologia , Hormônios Esteroides Gonadais/farmacologia , Masculino , Promegestona/metabolismo , Receptores de Progesterona/efeitos dos fármacos
17.
Neuroreport ; 8(3): 653-8, 1997 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-9106741

RESUMO

In this study we sought to validate physiologically the hypothalamus afferent projections from the auditory thalamus previously identified with tract tracing techniques in the ring dove. In total, we recorded the responses of 628 units in the nucleus ovoidalis (Ov) and its shell region to electrical stimulation applied to anterior hypothalamus and ventromedial nucleus. Ninety-six acoustic units in the shell region displayed good antidromic responses, confirming this region's axonal projections into these nuclei of the hypothalamus. Orthodromic responses (143 units) recorded in the Ov-Ov shell region suggest on the other hand reciprocal projections from the hypothalamus back to the auditory thalamus.


Assuntos
Vias Aferentes/fisiologia , Mapeamento Encefálico , Hipotálamo/fisiologia , Neurônios/fisiologia , Núcleos Talâmicos/fisiologia , Animais , Percepção Auditiva/fisiologia , Columbidae , Estimulação Elétrica , Potenciais Evocados , Feminino , Lateralidade Funcional , Hipotálamo Anterior/fisiologia , Masculino , Núcleo Hipotalâmico Ventromedial/fisiologia
18.
Neuroreport ; 4(6): 727-30, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8347816

RESUMO

Pathways associated with a recently defined region of the avian auditory thalamus, the shell of the nucleus ovoidalis (Ov), were examined for met-enkephalin immunoreactivity. The presence of enkephalin-like immunoreactive (ELI) perikarya within the medial margin of the inferior colliculus (ICM), afferent to the Ov shell, implicated ICM as a source of ELI fibers within the Ov shell and tract. The shell also contained ELI perikarya and its targets, including the ventromedial hypothalamus and caudoventral paleostriatal complex, were characterized by ELI fields. These data suggest that enkephalinergic auditory pathways, in parallel with traditionally recognized auditory projections, target regions of the avian basal forebrain.


Assuntos
Vias Auditivas/metabolismo , Aves/fisiologia , Encefalina Metionina/metabolismo , Animais , Vias Auditivas/imunologia , Axônios/fisiologia , Encefalina Metionina/imunologia , Técnicas Imunoenzimáticas , Imuno-Histoquímica , Colículos Inferiores/citologia , Colículos Inferiores/fisiologia , Lisina/análogos & derivados , Fito-Hemaglutininas
19.
Brain Res ; 207(2): 279-301, 1981 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-7470910

RESUMO

The involvement of the nucleus intercollicularis (ICo) region of the midbrain, an estrogen-sensitive area, in the expression of estrogen-dependent female courtship behavior was examined with radiofrequency lesion and intracranial hormone implant techniques. Bilateral lesions in the ICo region caused a reduction in the female's nest coos, and no reduction in other behaviors in response to male courtship. In addition, the follicles of the ICo lesioned females failed to grow in response to male courtship. A second experiment showed that the difference in follicular size between ICo-lesioned and sham-ICo-lesioned females was not observed if females were visually isolated from males, suggesting that tonic ovarian activity was not affected by ICo lesions. In the third experiment, unilateral 30-gauge implant containing estrogen (E) or estradiol benzoate (EB) in the ICo region of bilaterally ovariectomized females restored the nest-coo, though not to the level obtained with systemic EB injections. Other behaviors were not selectively affected by E or EB implants in the ICo region. Diffusion from the implant was probably not responsible for the elicitation of the nest-coo, since the oviduct weights of females implanted with E or EB and cholesterol did not differ. These data are consistent with the hypothesis that the ICo region is involved in the expression of vocal (cooing) courtship behavior in the female ring dove.


Assuntos
Estrogênios/fisiologia , Comportamento Sexual Animal/fisiologia , Animais , Mapeamento Encefálico , Columbidae , Dominância Cerebral/fisiologia , Estradiol/fisiologia , Feminino , Mesencéfalo/fisiologia , Degeneração Neural , Folículo Ovariano/crescimento & desenvolvimento , Isolamento Social , Vocalização Animal/fisiologia
20.
Am J Prev Med ; 15(3): 172-7, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9791634

RESUMO

OBJECTIVES: To determine the incidence of nonfatal school-related injuries in adolescent schoolchildren. DESIGN: Nurses completed a Student Accident Report Form (SARF) on all injuries in schools meeting standardized criteria from September 1995 to June 1996. SETTING: Six junior high schools in Kaohsiung city, Taiwan. SUBJECTS: 13,335 adolescents aged 13-15 in six schools. RESULTS: A total of 3,640 injuries were reported among the city's 13,335 students, for an overall injury rate of 27.3 injuries/100 student years. Injury rates were higher for boys than for girls at all grade levels. The seventh-grade students had the highest incidence rate. Injuries not involving other students accounted for nearly 64% of all injuries. Injuries occurring on the playground/gymnasium and classroom were the two most common types and were more than twice as frequent as injuries occurring in the hall or stairs. Contusions, abrasions, and swelling were the most frequently reported types of injuries. The body sites most frequently injured were the extremities. When exposure time is taken into account, injury rates were higher in the unsupervised areas of the schools. CONCLUSIONS: School-related injury incidence among adolescents attending junior high school is higher than has been previously reported and should be recognized as a significant public health problem in Taiwan.


Assuntos
Instituições Acadêmicas , Ferimentos e Lesões/epidemiologia , Acidentes/estatística & dados numéricos , Adolescente , Feminino , Humanos , Masculino , Taiwan
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