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1.
Sci Rep ; 14(1): 9378, 2024 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654029

RESUMO

Uneven rainfall and high temperature cause drought in tropical and subtropical regions which is a major challenge to cultivating summer mung bean. Potassium (K), a major essential nutrient of plants can alleviate water stress (WS) tolerance in plants. A field trial was executed under a rainout shelter with additional K fertilization including recommended K fertilizer (RKF) for relieving the harmful impact of drought in response to water use efficiency (WUE), growth, yield attributes, nutrient content, and yield of mung bean at the Regional Agricultural Research Station, BARI, Ishwardi, Pabna in two successive summer season of 2018 and 2019. Drought-tolerant genotype BMX-08010-2 (G1) and drought-susceptible cultivar BARI Mung-1 (G2) were grown by applying seven K fertilizer levels (KL) using a split-plot design with three replications, where mung bean genotypes were allotted in the main plots, and KL were assigned randomly in the sub-plots. A considerable variation was observed in the measured variables. Depending on the different applied KL and seed yield of mung bean, the water use efficiency (WUE) varied from 4.73 to 8.14 kg ha-1 mm-1. The treatment applying 125% more K with RKF (KL7) under WS gave the maximum WUE (8.14 kg ha-1 mm-1) obtaining a seed yield of 1093.60 kg ha-1. The treatment receiving only RKF under WS (KL2) provided the minimum WUE (4.73 kg ha-1 mm-1) attaining a seed yield of 825.17 kg ha-1. Results showed that various characteristics including nutrients (N, P, K, and S) content in stover and seed, total dry matter (TDM) in different growth stages, leaf area index (LAI), crop growth rate (CGR), root volume (RV), root density (RD), plant height, pod plant-1, pod length, seeds pod-1, seed weight, and seed yield in all pickings increased with increasing K levels, particularly noted with KL7. The highest grain yield (32.52%) was also obtained from KL7 compared to lower K with RKF. Overall, yield varied from 1410.37 kg ha-1 using 281 mm water (KL1; well-watered condition with RKF) to 825.17 kg ha-1 using 175 mm water (KL2). The results exhibited that the application of additional K improves the performance of all traits under WS conditions. Therefore, mung beans cultivating under WS requires additional K to diminish the negative effect of drought, and adequate use of K contributes to accomplishing sustainable productivity.


Assuntos
Secas , Potássio , Vigna , Vigna/crescimento & desenvolvimento , Vigna/genética , Vigna/efeitos dos fármacos , Potássio/metabolismo , Água/metabolismo , Fertilizantes , Nutrientes/metabolismo , Genótipo , Sementes/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/metabolismo , Desidratação , Resistência à Seca
2.
Plants (Basel) ; 11(11)2022 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-35684294

RESUMO

In order to develop high-yielding genotypes of adapted maize, multilocation trials of maize were performed including forty-five maize hybrids exploiting genetic variability, trait associations, and diversity. The experiments were laid out in an RCB design and data were recorded on eight yield and yield-contributing traits, viz., days to anthesis (AD), days to silking (SD), anthesis-silking interval (ASI), plant height (PH), ear height (EH), kernels per ear (KPE), thousand-kernel weight (TKW), and grain yield (GY). An analysis of variance (ANOVA) showed significant variation present among the different traits under study. The phenotypic coefficient of variance (PCV) showed a higher value than the genotypic coefficient of variance (GCV), indicating the environmental influence on the expression of the traits. High heritability coupled with high genetic advance was found for these traits, indicative of additive gene action. The trait associations showed that genotypic correlation was higher than phenotypic correlation. Based on genetic diversity, the total genotypes were divided into four clusters, and the maximum number of 16 genotypes was found in cluster IV. Among the eight yield and yield-contributing traits, PH, ASI, EH, and TKW were the important traits for variability creation and were mostly responsible for yield. Genotypes G5, G8, G27, G29, and G42 were in the top ranks based on grain yield over locations, while a few others showed region-centric performances; all these genotypes can be recommended upon validation for commercial release. The present findings show the existence of proper genetic variability and divergence among traits, and the identified traits can be used in a maize improvement program.

3.
Food Waterborne Parasitol ; 27: e00157, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35518125

RESUMO

Parasitic ascaridoid nematodes occur in a wide range of marine organisms across the globe. Some species of the anisakid family (Ascaridoidea: Anisakidae) can cause gastrointestinal disease in humans (i. e. anisakidosis). Despite their importance as potentially hazardous parasites, the occurrence and infection characteristics of ascaridoids are still poorly known from many host species and geographical areas. This study investigated the diversity and infection levels of ascaridoid parasites in various commercial fish and squid host species off Bangladesh. Fish and squid specimens were visually inspected for nematodes using the UV-press method. Nematodes were assigned to genus level based on morphology and identified by sequence analyses of the entire ITS region and partial 28S rDNA and mtDNA cox2 genes. Third-stage larvae (L3) of Anisakis typica occurred at low prevalence (P = 10% and 8%, respectively) in the viscera of Selar crumenophthalmus and Trichiurus lepturus, while Hysterothylacium amoyense occurred in the viscera of Sardinella fimbriata (P = 1%) and the viscera and muscle of Harpadon nehereus (P = 32%) and T. lepturus (P = 76%). Lappetascaris sp. Type A L3 occurred in the mantle of the squid Uroteuthis duvaucelii (P = 11%). Anisakis and Lappetascaris species, and H. amoyense were firstly identified in the Bay of Bengal. The potentially zoonotic A. typica was only found in fish viscera. Hysterothylacium amoyense and Lappetascaris sp., both generally regarded as non-zoonotic, occurred at low prevalence in the muscle or mantle of fish or squid, respectively. Since consumption of raw or lightly processed seafood seems to be rare in Bangladesh, the risk of acquiring anisakidosis from consuming fishery products from off Bangladesh appears to be low. Due to its reddish appearance, the visual presence of H. amoyense larvae in fish flesh may represent a food quality issue.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32117692

RESUMO

BACKGROUND: Although there are thousands of patients with hepatocellular carcinoma (HCC) in Bangladesh, almost there is no nationwide recommendations for therapeutic maneuver for HCC patients. As most of the HCC patients of Bangladesh are diagnosed late, patients with advanced HCC with large and multiple HCC nodules represent the usual presentation of HCC. The study is presented here to assess the effects of a combined therapy of transarterial chemoembolization (TACE) and sorafenib in advanced HCC patients. MATERIALS AND METHODS: A total of 77 patients with advanced HCC were enrolled in this study. All of them had advanced HCC with variable etiologies and clinical conditions. All patients were treated by TACE and also given systemic sorafenib at the same time. The patients were checked 1 and 3 months after therapy commencement. RESULTS: Out of 77 patients, 18 patients died within 1 month and additional 15 patients died within 3 months after therapy commencement. Thus, there remains 44 surviving patients after 3 months. When different parameters of dead patients and survived patients were compared, no specific parameters dictated the factors about overall survival of more than 3 months. DISCUSSION: This is the first approach to initiate an invasive and a systemic therapy for treatment of advanced HCC in Bangladesh. Further follow-up of patients and their long-term overall survival may cast some lights about the role of these therapies in Bangladeshi HCC patients. HOW TO CITE THIS ARTICLE: Al Mahtab, M, Rahim MA, Noor-E-Alam SM, et al. Treatment by Transarterial Chemoembolization and Sorafenib for Hepatocellular Carcinoma vs Advanced Hepatocellular Carcinoma in Bangladesh: A Real-life Situation. Euroasian J Hepato-Gastroenterol 2019;9(2):63-66.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31988869

RESUMO

How to cite this article: Mahtab MAL, Akbar SMF, et al. Alarming Levels of Hepatitis C Virus Prevalence among Rohingya Refugees in Bangladesh: Emergency National and International Actions Warranted. Euroasian J Hepatogastroenterol 2019;9(1):55-56.

6.
Hepatol Int ; 11(6): 540-546, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28840583

RESUMO

BACKGROUND AND PURPOSE: Mobilization of bone marrow-derived stem cells by granulocyte colony stimulating factor (G-CSF) supports hepatic regeneration and may augment clinical improvement in patients with acute-on-chronic liver failure (ACLF). The aim of this study is to assess the impact of G-CSF on complications and transplant-free survival in patients with ACLF. METHODS: Thirty-two patients with ACLF defined by Asian Pacific Association for the Study of the Liver (APASL) criteria were openly randomized to control (group A) or intervention (group B) receiving G-CSF (5 µg/kg/day, for 6 consecutive days) in addition to standard medical therapy with antiviral drugs. The patients were followed for 90 days. RESULTS: Simultaneous use of G-CSF and antiviral drugs in hepatitis B virus (HBV) ACLF significantly improved survival over antiviral drugs alone. Incidence of hepatorenal syndrome and hyponatremia were reduced due to use of G-CSF. Baseline parameters of the two groups of patients were comparable. Child-Turcotte-Pugh (CTP) and Model for End-Stage Liver Disease (MELD), disease severity scores improved in patients treated with G-CSF, with significant difference only for the CTP score at 90 days follow-up. In addition, mean white blood cell (WBC) count at day 15 was significantly higher in G-CSF group in absence of infection compared with control group. CONCLUSIONS: G-CSF therapy improved survival and clinical recovery in HBV-ACLF. G-CSF therapy also prevented renal failure and hyponatremia. We strongly recommend use of G-CSF therapy in addition to standard medical therapy.


Assuntos
Insuficiência Hepática Crônica Agudizada/tratamento farmacológico , Insuficiência Hepática Crônica Agudizada/virologia , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Hepatite B Crônica/complicações , Insuficiência Hepática Crônica Agudizada/sangue , Insuficiência Hepática Crônica Agudizada/complicações , Adolescente , Adulto , Antivirais/uso terapêutico , Quimioterapia Combinada , Feminino , Hepatite B Crônica/tratamento farmacológico , Síndrome Hepatorrenal/etiologia , Humanos , Hiponatremia/etiologia , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Índice de Gravidade de Doença , Taxa de Sobrevida , Adulto Jovem
7.
Can J Physiol Pharmacol ; 90(11): 1490-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23078220

RESUMO

We have measured the responses to endurance exercise training on body composition and glucose regulation, as well as cardiovascular and liver structure and function in rats fed a high carbohydrate and high fat (HCHF) diet as a model of human metabolic syndrome. Male Wistar rats (9-10 weeks old) were randomly allocated into corn starch (CS) or HCHF diet groups for 16 weeks; half of each group were exercised on a treadmill for 20, 25, and then 30 min/day, 5 days/week, during the last 8 weeks of the protocol. Metabolic, cardiovascular, and liver parameters were monitored. The HCHF diet induced symptoms of metabolic syndrome, including obesity, dyslipidemia, impaired glucose tolerance, and increased systolic blood pressure associated with the development of cardiovascular remodeling and nonalcoholic steatohepatitis. Exercise in HCHF rats decreased body mass, abdominal fat pads and circumference, blood glucose concentrations, plasma lipid profiles, systolic blood pressure, left ventricular diastolic stiffness, collagen deposition and inflammatory cell infiltration in the left ventricle, improved aortic contractile and relaxation responses, and decreased liver mass and hepatic fat accumulation. This study demonstrates that endurance exercise is effective in this rat model of diet-induced metabolic syndrome in improving body composition and glucose regulation, as well as cardiovascular and liver structure and function.


Assuntos
Modelos Animais de Doenças , Síndrome Metabólica/terapia , Esforço Físico , Animais , Aorta Torácica/imunologia , Aorta Torácica/patologia , Aorta Torácica/fisiopatologia , Composição Corporal , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Dieta Hiperlipídica/efeitos adversos , Carboidratos da Dieta/efeitos adversos , Dislipidemias/etiologia , Dislipidemias/prevenção & controle , Fígado Gorduroso/etiologia , Fígado Gorduroso/prevenção & controle , Intolerância à Glucose/etiologia , Intolerância à Glucose/prevenção & controle , Ventrículos do Coração/imunologia , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Hipertensão/etiologia , Hipertensão/prevenção & controle , Fígado/imunologia , Fígado/patologia , Masculino , Síndrome Metabólica/etiologia , Síndrome Metabólica/imunologia , Síndrome Metabólica/fisiopatologia , Hepatopatia Gordurosa não Alcoólica , Obesidade/complicações , Obesidade/prevenção & controle , Distribuição Aleatória , Ratos , Ratos Wistar
8.
Zoolog Sci ; 28(11): 845-52, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22035308

RESUMO

Differentiation and development of steroid-producing cells (SPCs) and folliculogenesis during ovarian differentiation in the Nile tilapia Oreochromis niloticus were immunohistochemically and ultrastructurally examined. Clusters of immunopositive cells (IPCs) against antibodies (ABs) of cholesterol side-chain cleavage cytochrome P450 (P450scc), 3ß-hydroxysteroid dehydrogenase (3ßHSD), and cytochrome P450aromatase (P450arom) only appeared in the area near blood vessels in the fish ovaries at 50-60 days after hatching (dah). Ultrastructural results showed that differentiation and development of SPCs from undifferentiated to maturation occurred in the area near blood vessels, indicating that it would be the original site of SPCs. At 70-80 dah, IPC clusters invaded the interstices among oocytes at the perinucleolar stage from the area near the blood vessels. IPCs increased in number in the interstices among the previtellogenic oocytes, and some clusters began to enclose the outer thecal layer of the previtellogenic oocytes at 90 dah. The process of folliculogenesis was ultrastructurally observed. SPCs enclosed by fibroblastic cells invaded the interstitial areas among oocytes and some reached the surfaces of oocytes. The upper portions of these elongations opened and began to enclose the outer surfaces of developed oocytes to become thecal layer. Later, newly migrated SPCs reach the thecal layer to become thecal cells. These results indicate that steroid-producing thecal cells originate from the SPCs in the area near blood vessels. After thecal layer formation, an immunopositive reaction against P450arom AB, but not against P450scc or 3ß-HSD ABs, appeared first in the granulosa cells enclosing the vitellogenic oocytes at 100 dah. At this time, estrogen production in serum levels rapidly increased. Thus, folliculogenesis could be essential for active production of estrogen in the ovary.


Assuntos
Ciclídeos/crescimento & desenvolvimento , Ciclídeos/metabolismo , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Esteroides/metabolismo , Animais , Feminino , Imuno-Histoquímica , Ovário/ultraestrutura
9.
Artigo em Inglês | MEDLINE | ID: mdl-20227511

RESUMO

Follicle-stimulating hormone (FSH) and its receptor (FSHR) play important roles in spermatogenesis. We cloned and characterized the honeycomb grouper Epinephelus merra FSHR (EmFSHR) to elucidate its role in the protogynous sex change in groupers. Reverse transcription-polymerase chain reaction (RT-PCR) analysis suggested that EmFSHR was expressed exclusively in the gonads. In situ hybridization showed the distribution of EmFSHR in the granulosa cells of previtellogenic oocytes and Leydig cells in the testis. Quantitative reverse transcription PCR (RT-qPCR) analysis of gonadal EmFSHR transcripts during the process of sex change indicated that the lowest levels were found in the female phase before sex change. EmFSHR transcripts increased during the early transitional phase, when oocytes began to degenerate in parallel with the initiation of gonial germ cell differentiation into spermatogonia. A dramatic increase in EmFSHR transcription occurred during the late transitional phase, when the gonad contained numerous proliferating male germ cells and many degenerated oocytes. EmFSHR expression remained high until the transformation from ovary to testis was complete. The data reveal that female to male sex change is associated with the upregulation of EmFSHR transcripts, and that this upregulation may be responsible for the development of testicular tissue and the progression of spermatogenesis. Furthermore, how the upregulation of EmFSHR is controlled in the initiation of sex change remains to be elucidated.


Assuntos
Transtornos do Desenvolvimento Sexual , Peixes/genética , Receptores do FSH/isolamento & purificação , Receptores do FSH/metabolismo , Sequência de Aminoácidos , Animais , DNA Complementar/genética , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Gônadas/citologia , Gônadas/metabolismo , Masculino , Dados de Sequência Molecular , Filogenia , Transporte de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores do FSH/química , Receptores do FSH/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Biol Reprod ; 82(6): 1030-6, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20147735

RESUMO

Recent studies have suggested that the hypothalamic-pituitary-gonadal axis is involved in gonadal sex change in sex-changing teleosts. However, its underlying mechanism remains largely unknown. In this study, we focused on the distinct roles of two gonadotropins (GTHs), follicle-stimulating hormone (FSH) and luteinizing hormone (LH), in the protogynous hermaphrodite teleost, honeycomb grouper (Epinephelus merra). First, we investigated the expression pattern of mRNAs for GTH subunits (cga, fshb, and lhb) in the pituitaries from fish at the different sexual phases. Real-time RT-PCR analyses showed that fhsb mRNA levels in the female pituitary were low. However, fshb transcripts increased dramatically in association with testis development. In contrast, levels of cga and lhb mRNAs did not significantly vary during sex change. In addition, immunohistochemical observations of Fshb- and Lhb-producing cells in the pituitary, through the use of specific antibodies for detections of teleost GTH subunits, were consistent with sexually dimorphic expression of Fshb. In order to identify the role of GTH in gonad of honeycomb grouper, we treated females with bovine FSH (50 or 500 ng/fish) or LH (500 ng/fish) in vivo. After 3 wk, FSH treatments induced female-to-male sex change and up-regulated endogenous androgen levels and fshb transcripts, whereas LH treatment had no effect on sex change. These results suggest that FSH may trigger the female-to-male sex change in honeycomb grouper.


Assuntos
Bass/fisiologia , Hormônio Foliculoestimulante/fisiologia , Gonadotropinas Hipofisárias/biossíntese , Organismos Hermafroditas , Hipófise/fisiologia , Caracteres Sexuais , Processos de Determinação Sexual , Androgênios/análise , Animais , Bovinos , Feminino , Hormônio Luteinizante/fisiologia , Masculino , RNA Mensageiro/análise , Testículo/crescimento & desenvolvimento
11.
Rev. bras. farmacogn ; 18(4): 521-526, Oct.-Dec. 2008. tab
Artigo em Inglês | LILACS | ID: lil-509043

RESUMO

The results of neuropharmacological, microbiological and toxicological studies on the ethanol extract of the bark of Excoecaria agallocha are reported. The extract (100 and 200 mg/kg dosages) was found to produce a profound decrease in exploratory activity in a dose-dependent manner. It also showed a marked sedative effect as evidenced by a significant reduction in gross behaviour and potentiation of sodium thiopental-induced sleeping time. The totality of these effects showed that the extract possesses depressant action on the central nervous system (CNS). The extract of E. agallocha exhibited significant in vitro antibacterial activity against Staphylococcus aureus, Shigella dysenteriae, Shigella sonnei and Enterococci with the zones of inhibition ranging from 11 to 15 mm. While the extract showed considerable brine shrimp toxicity (LD50 = 20 mg/mL), it displayed only low level of toxicity in mice.


Os resultados dos estudos neurofarmacológicos, microbiológicos e toxicológicos do extrato etanólico da casca de Excoecaria agallocha são reportados. O extrato (dosagens de 100 e 200 mg/kg) produziu uma diminuição profunda na atividade exploratória de maneira dose-dependente. Ele também mostrou um efeito sedativo marcante conforme evidenciado por uma redução significativa no comportamento total e potencialização do tempo de sono induzido por tiopental sódico. A totalidade destes efeitos mostrou que o extrato possui ação depressora sobre o sistema nervoso central (SNC). O extrato de E. agallocha exibiu significante atividade antibacteriana in vitro contra Staphylococcus aureus, Shigella dysenteriae, Shigella sonnei e Enterococci com as zonas de inibição medindo entre 11 a 15 mm. Enquanto o extrato mostrou considerável toxicidade em Artemia salina (DL50 = 20 mg/mL), ele exibiu apenas baixo nível de toxicidade em camundongos.

12.
Gen Comp Endocrinol ; 157(1): 75-85, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18452918

RESUMO

The honeycomb grouper (Epinephelus merra) is one of the smallest members of the Serranidae family and is often used to study protogynous sex change. To determine the role of the male-determining gene Dmrt1 and the ovarian-specific gene Foxl2 in sex change, we cloned these two markers from E. merra gonads by reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). Two isoforms, Dmrt1a and Dmrt1b, resulted from alternative splicing in the coding region, causing the insertion of one glutamine residue in Dmrt1b. RT-PCR revealed that Dmrt1 was expressed only in the gonads, with higher levels in the testis than in the ovary. cDNA encoding Foxl2 was isolated from the ovary; Foxl2 was expressed extensively in the brain, pituitary, gonads, and gill, with its highest level in the ovary, indicating a potential role for Foxl2 in the brain-pituitary-gonad axis. Real-time quantitative RT-PCR analyses showed that Foxl2 mRNA expression was significantly downregulated from the late transitional phase to the completion of sex change. Conversely, Dmrt1 expression increased with the progression of spermatogenesis and continued until the formation of the testis. The expression profiles of these two sex-specific marker genes corresponded closely with the histological process of sex change. The down-regulation of Foxl2 most likely facilitates oocyte degeneration, whereas the up-regulation of Dmrt1 causes the proliferation of gonial germ cells into spermatogina and initiates sex change.


Assuntos
Proteínas de Peixes/genética , Fatores de Transcrição Forkhead/genética , Organismos Hermafroditas , Perciformes/genética , Processos de Determinação Sexual , Fatores de Transcrição/genética , Animais , Clonagem Molecular , Feminino , Expressão Gênica , Masculino , Técnicas de Amplificação de Ácido Nucleico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Zoolog Sci ; 23(1): 65-9, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16547407

RESUMO

The honeycomb grouper, Epinephelus merra, is a protogynous hermaphrodite fish. Sex steroid hormones play key roles in sex change of this species. A significant drop in endogenous estradiol-17beta (E2) levels alone triggers female-to-male sex change, and the subsequent elevation of 11-ketotestosterone (11KT) levels correlates with the progression of spermatogenesis. To elucidate the role of an androgen in sex change, we attempted to induce female-to-male sex change by exogenous 11KT treatments. The 75-day 11KT treatment caused 100% masculinization of pre-spawning females. Ovaries of the control (vehicle-treated) fish had oocytes at various stages of oogenesis, while the gonads of the 11KT-treated fish had transformed into testes; these contained spermatogenic germ cells at various stages, including an accumulation of spermatozoa in the sperm duct. In the sex-changed fish, plasma levels of E2 were significantly low, while both testosterone (T) and 11KT were significantly increased. Our results suggest that 11KT plays an important role in sex change in the honeycomb grouper. Whether the mechanism of 11KT-induced female-to-male sex change acts through direct stimulation of spermatogenesis in the ovary or via the inhibition of estrogen synthesis remains to be clarified.


Assuntos
Androgênios/metabolismo , Estradiol/metabolismo , Organismos Hermafroditas , Perciformes/fisiologia , Processos de Determinação Sexual , Testosterona/análogos & derivados , Androgênios/farmacologia , Animais , Estradiol/sangue , Estradiol/farmacologia , Feminino , Fertilidade/fisiologia , Masculino , Especificidade da Espécie , Espermatogênese , Testosterona/sangue , Testosterona/metabolismo , Testosterona/farmacologia
14.
Mol Reprod Dev ; 73(2): 206-14, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16261615

RESUMO

11-ketotestosterone (11-KT), a potent male-specific androgen in fish, has important roles on spermatogenesis, male behavior, and nuptial coloration. The site of 11-KT synthesis and its role on male germ cell development during protogynous sex change is not clearly understood. We examined the dynamics of steroidogenic enzymes immunolocalization, viz cholesterol side-chain cleavage (P450scc), biomarker of steroids and cytochrome P45011beta-hydroxylase (P45011beta), downstream to 11-KT production, throughout the process of sex change in honeycomb grouper (Epinephelus merra). In female, P450scc immunoreactivity (-ir) was observed in the theca layer and tunica near blood vessels (BV). During the onset of sex change, P450scc reactive cells were observed in the remaining follicle layer of degenerated oocyte of the ovo-testis in early transitional (ET) and late transitional (LT). In male, P450scc-ir was localized in the interstitial Legdig cells of testis. P45011beta reactive cells were observed in the tunica near BV in female but not in theca layer. In ET and LT phases gonads, P45011beta localized in remaining follicle layer of degenerated oocyte and tunica near BV. On the other hand, in male, both interstices and tunica near BV showed strong signals against P45011beta. Moreover, in vivo and in vitro levels of 11-KT related with the changes in the nuclei diameter of P45011beta-positive cells in both tunica near BV and remaining follicle layer of degenerated oocyte to interstices during the progress of sex change. The present results suggest that 11-KT produced in the tunica near BV may provide the stimulus for female to degenerate oocytes and initiate sex change. However, 11-KT produced both in tunica near BV and remaining follicle layer of degenerated oocyte possibly plays critical role during testicular differentiation as well as gonadal restructuring at mid to late phases (ET to LT) of sex change in honeycomb grouper.


Assuntos
Androgênios/metabolismo , Bass/fisiologia , Organismos Hermafroditas , Processos de Determinação Sexual , Testosterona/análogos & derivados , Animais , Núcleo Celular/ultraestrutura , Tamanho Celular , Sistema Enzimático do Citocromo P-450/metabolismo , Feminino , Hormônios Esteroides Gonadais/metabolismo , Imuno-Histoquímica , Técnicas In Vitro , Masculino , Caracteres Sexuais , Testosterona/fisiologia
15.
J Exp Zool A Comp Exp Biol ; 303(6): 497-503, 2005 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15880758

RESUMO

Circulating estradiol-17beta (E2) levels decrease precipitously during female to male (protogynous) sex change in fish. Whether this drop in E2 levels is a cause or consequence of sex change is still largely unknown. The present study treated adult female honeycomb groupers (Epinephelus merra) with aromatase inhibitor (AI, Fadrozole), either alone or in combination with E2, to investigate the role of estrogen in protogynous sex change. Control fish had ovaries undergoing active vitellogenesis; the gonads of AI-treated fish had already developed into testes, which produced sperm capable of fertilization. In contrast, co-treatment of fish with E2 completely blocked AI-induced sex reversal. AI treatment significantly reduced circulating levels of E2, whereas the addition of E2 to AI prevented the loss. The plasma androgen (testosterone and 11-ketotestosterone) levels were increased in the AI-treated fish, while the levels in the E2-supplemented fish were low compared to controls. Present results show that E2 plays an important role in maintaining female sex of hermaphrodite fishes, and that the inhibition of E2 synthesis causes oocyte degeneration leading to testicular differentiation in the ovary.


Assuntos
Estradiol/metabolismo , Gônadas/efeitos dos fármacos , Organismos Hermafroditas , Perciformes/metabolismo , Processos de Determinação Sexual , Análise de Variância , Androgênios/metabolismo , Animais , Inibidores da Aromatase/farmacologia , Estradiol/farmacologia , Fadrozol/farmacologia , Feminino , Gônadas/citologia , Técnicas Histológicas , Japão , Masculino
16.
Cell Tissue Res ; 320(2): 323-9, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15778855

RESUMO

Androgen plays an important role in the developing ovaries of female fish. However, little is known regarding either the sites of production of androgen or its functional roles. In the present study, we investigated immunohistochemically the localization of cholesterol-side-chain-cleavage (P450scc) and cytochrome P45011beta-hydroxylase (P45011beta) with antibodies P450scc and P45011beta in the ovary of the female honeycomb grouper Epinephelus merra during its reproductive cycle. Clusters of strongly immunopositive cells, with 100-1000 cells in each cluster, against both P450scc and P45011beta, were observed throughout the annual reproductive cycle in tissue near blood vessels in the tunica ovary surrounding the outer periphery of the ovary. The ultrastructural characteristics of these cells showed that they were steroid-producing cells. In contrast, immunopositive cells against P450scc but not against P45011beta were localized in the theca layer surrounding the outer periphery of oocytes. These results suggest that two distinct steroid biosynthesis sites exist in the ovary and that cells at the two sites differ functionally. The only cells that biosynthesize 11-ketotestosterone are found in clusters in the vicinity of blood vessels; they possibly play a physiological role in oocyte growth and gonadal restructuring during the sex change of individuals of this species.


Assuntos
Androgênios/biossíntese , Imuno-Histoquímica , Ovário/metabolismo , Perciformes/fisiologia , Animais , Western Blotting , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Feminino , Oxigenases de Função Mista/metabolismo , Modelos Biológicos , Ovário/ultraestrutura , Perciformes/anatomia & histologia
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