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1.
Biofactors ; 50(3): 608-618, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38135490

RESUMO

The high-density lipoprotein (HDL)-associated enzyme paraoxonase 1 (PON1) is expressed almost exclusively in the liver and is then transported by HDL to the peripheral tissues. The lipophilic nature of PON1 enables its easy exchange between the lipoprotein and cell membranes in a process that is dependent on the HDL receptor scavenger receptor class B, type 1 (SR-B1). In endothelial cells, PON1 binding to the cell membrane leads to its internalization by endocytosis and subsequent lysosomal degradation. PON1 is a "promiscuous" enzyme with unusually broad substrate specificity in vitro, but its actual function and substrate are still unknown. The enzyme requires a lipid environment and becomes completely inactive upon delipidation. However, when PON1 binds HDL, its active site faces the lipoprotein's core and is inaccessible to external substrates. Hence, the HDL-bound PON1 is inactive toward substrates outside the particle's lipid core and is rapidly degraded and becomes inactive upon internalization. Consequently, the enzyme is only active in the cell membrane during its transit from HDL to the cytoplasm. To assign a function to PON1, we investigated whether it is a palmitoyl-protein thioesterase (PPT) that can hydrolyze the palmitoyl moieties of membrane proteins involved in HDL and cholesterol transport, such as SR-B1, ABCA1, or their neighboring caveola proteins to facilitate the release of HDL or trigger its endocytosis. This study shows that PON1 can hydrolyze palmitoyl-cysteine thioester bonds in vitro, has direct or indirect PPT activity in vivo, and can significantly decrease the presence of SR-B1 in the endothelial membrane.


Assuntos
Arildialquilfosfatase , Membrana Celular , Lipoproteínas HDL , Receptores Depuradores Classe B , Tioléster Hidrolases , Arildialquilfosfatase/metabolismo , Arildialquilfosfatase/genética , Tioléster Hidrolases/metabolismo , Tioléster Hidrolases/genética , Humanos , Membrana Celular/metabolismo , Receptores Depuradores Classe B/metabolismo , Receptores Depuradores Classe B/genética , Lipoproteínas HDL/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/enzimologia , Células Endoteliais da Veia Umbilical Humana , Animais , Endocitose/fisiologia
2.
Cells ; 12(13)2023 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-37443828

RESUMO

Anxiety and metabolic impairments are often inter-related, but the underlying mechanisms are unknown. To seek RNAs involved in the anxiety disorder-metabolic disorder link, we subjected zebrafish larvae to caffeine-induced anxiety or high-fat diet (HFD)-induced obesity followed by RNA sequencing and analyses. Notably, differentially expressed (DE) transcripts in these larval models and an adult zebrafish caffeine-induced anxiety model, as well as the transcript profiles of inherently anxious versus less anxious zebrafish strains and high-fat diet-fed versus standard diet-fed adult zebrafish, revealed inversely regulated DE transcripts. In both larval anxiety and obesity models, these included long noncoding RNAs and transfer RNA fragments, with the overrepresented immune system and inflammation pathways, e.g., the "interleukin signaling pathway" and "inflammation mediated by chemokine and cytokine signaling pathway". In adulthood, overrepresented immune system processes included "T cell activation", "leukocyte cell-cell adhesion", and "antigen processing and presentation". Furthermore, unlike adult zebrafish, obesity in larvae was not accompanied by anxiety-like behavior. Together, these results may reflect an antagonistic pleiotropic phenomenon involving a re-adjusted modulation of the anxiety-metabolic links with an occurrence of the acquired immune system. Furthermore, the HFD potential to normalize anxiety-upregulated immune-related genes may reflect the high-fat diet protection of anxiety and neurodegeneration reported by others.


Assuntos
Cafeína , Peixe-Zebra , Animais , Peixe-Zebra/genética , Larva , Cafeína/farmacologia , Obesidade/genética , Obesidade/metabolismo , Inflamação , Ansiedade
3.
J Assist Reprod Genet ; 39(11): 2625-2633, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36264444

RESUMO

PURPOSE: To report outcome of planned oocyte cryopreservation (POC) in the first 8 years of this treatment in our center. METHODS: A retrospective study in a university-affiliated medical center. RESULTS: A total of 446 women underwent POC during 2011-2018. Fifty-seven (13%) women presented to use these oocytes during the study period (until June 2021). POC was performed at a mean age of 37.9 ± 2.0 (range 33-41). Age at thawing was 43.3 ± 2.1 (range 38-49). A total of 34 (60%) women transferred their oocytes for thawing at other units. Oocyte survival after thawing was significantly higher at our center than following shipping to ancillary sites (78 vs. 63%, p = 0.047). Forty-nine women completed their treatment, either depleting their cryopreserved oocytes without conceiving (36) or attaining a live birth (13)-27% live birth rate per woman. Only one of eleven women who cryopreserved oocytes aged 40 and older had a live birth using thawed oocytes. CONCLUSION: Women should be advised to complete planned oocyte cryopreservation before age 40, given low success rates in women who underwent cryopreservation at advanced reproductive age. In this study, oocyte shipping was associated with lower survival rate. These findings may be relevant for women considering POC and utilization of cryopreserved oocytes.


Assuntos
Criopreservação , Transferência Embrionária , Gravidez , Feminino , Humanos , Masculino , Taxa de Gravidez , Estudos Retrospectivos , Oócitos
4.
Oxid Med Cell Longev ; 2022: 2253478, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464770

RESUMO

The recently described phenomenon of cholesterol-loaded low-density lipoproteins (LDL) entering the arterial wall from the lumen by transcytosis has been accepted as an alternative for the long-held concept that atherogenesis involves only passive LDL movement across an injured or dysfunctional endothelial barrier. This active transport of LDL can now adequately explain why plaques (atheromas) appear under an intact, uninjured endothelium. However, the LDL transcytosis hypothesis is still questionable, mainly because the process serves no clear physiological purpose. Moreover, central components of the putative LDL transcytosis apparatus are shared by the counter process of cholesterol efflux and reverse cholesterol transport (RCT) and therefore can essentially create an energy-wasting futile cycle and paradoxically be pro- and antiatherogenic simultaneously. Hence, by critically reviewing the literature, we wish to put forward an alternative interpretation that, in our opinion, better fits the experimental evidence. We assert that most of the accumulating cholesterol (mainly as LDL) reaches the intima not from the lumen by transcytosis, but from the artery's inner layers: the adventitia and media. We have named this directional cholesterol transport transmural cholesterol flux (TCF). We suggest that excess cholesterol, diffusing from the avascular (i.e., devoid of blood and lymph vessels) media's smooth muscle cells, is cleared by the endothelium through its apical membrane. A plaque is formed when this cholesterol clearance rate lags behind its rate of arrival by TCF.


Assuntos
Aterosclerose , Placa Aterosclerótica , Aorta/metabolismo , Colesterol , LDL-Colesterol , Humanos , Lipoproteínas LDL/metabolismo , Transcitose
5.
Appl Opt ; 58(36): 9815-9822, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31873625

RESUMO

We describe a new method for the accurate measurement of optical rotation. It is based on curve-fitting the signal of a new optical rotation polarimeter that we have recently developed. The calculated accuracy ($\sim{80}\,\,\unicode{x00B5} ^\circ $∼80µ∘), and precision ($\sim{220}\,\,\unicode{x00B5} ^\circ )$∼220µ∘) are potentially useful for various applications in the fields of biomedical devices and analytical chemistry.

6.
Isr Med Assoc J ; 18(6): 313-7, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27468521

RESUMO

BACKGROUND: Fertility treatments are responsible for the rise in high order pregnancies in recent decades and their associated complications. Reducing the number of embryos returned to the uterus will reduce the rate of high order pregnancies. OBJECTIVES: To explore whether obstetric history and parity have a role in the clinician's decision making regarding the number of embryos transferred to the uterus during in vitro fertilization (IVF). METHODS: In a retrospective study for the period August 2005 to March 2012, data of twin deliveries > 24 weeks were collected, including parity, mode of conception (IVF vs. spontaneous), gestational age at delivery, preeclampsia, birth weight, admission to the neonatal intensive care unit (NICU), and Apgar scores. RESULTS: A total of 1651 twin deliveries > 24 weeks were record- ed, of which 959 (58%) were at term (> 37 weeks). The early preterm delivery (PTD) rate (< 32 weeks) was significantly lower with increased parity (12.6%, 8.5%, and 5.6%, in women with 0, 1, and ≥ 2 previous term deliveries, respectively). Risks for PTD (< 37 weeks), preeclampsia and NICU admission were significantly higher in primiparous women compared to those who had one or more previous term deliveries. Primiparity and preeclampsia, but not IVF, were significant risk factors for PTD. CONCLUSIONS: The risk for PTD in twin pregnancies is significantly lower in women who had a previous term delivery and decreases further after two or more previous term deliveries. This finding should be considered when deciding on the number of embryos to be transferred in IV.


Assuntos
Transferência Embrionária , Fertilização in vitro , Nascimento Prematuro , Adulto , Índice de Apgar , Parto Obstétrico/estatística & dados numéricos , Transferência Embrionária/efeitos adversos , Transferência Embrionária/métodos , Transferência Embrionária/estatística & dados numéricos , Feminino , Fertilização in vitro/efeitos adversos , Fertilização in vitro/métodos , Fertilização in vitro/estatística & dados numéricos , Idade Gestacional , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Israel/epidemiologia , Paridade , Gravidez , Resultado da Gravidez/epidemiologia , Gravidez de Gêmeos/estatística & dados numéricos , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , História Reprodutiva , Estudos Retrospectivos
7.
J Biomed Opt ; 21(7): 71104, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26720051

RESUMO

We comprehensively analyze the performance of a type of optical rotation (OR) polarimeter, which has been designed from the outset to fit the special requirements of two major applications: general chiral detection during the separation of optical isomers by high-pressure liquid chromatography systems in the pharmaceutical industry, and monitoring of glucose in the interstitial fluid of diabetics by a fully implanted long-term optical sensor. Both very demanding applications call for an OR polarimeter that can be miniaturized while maintaining high resolution and accuracy in the microdegree range in the face of considerable noise from various sources. These two characteristics­miniature size and immunity to noise­set this polarimeter apart from the traditional OR polarimeters currently in use, which are both bulky and very susceptible to noise. The following detailed analysis demonstrates the advantages of this polarimeter and its potential as an analytic and diagnostic tool.


Assuntos
Rotação Ocular , Óptica e Fotônica/instrumentação , Óptica e Fotônica/métodos , Desenho de Equipamento , Glucose/análise , Glucose/química , Modelos Lineares
8.
Fertil Steril ; 104(5): 1162-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26335130

RESUMO

OBJECTIVE: To evaluate the association between carriage of BRCA1/2 mutations and ovarian performance, as demonstrated by in vitro fertilization (IVF) outcomes. DESIGN: Retrospective cohort study. SETTING: Two tertiary IVF centers. PATIENT(S): BRCA mutation carriers undergoing IVF for preimplantation genetic diagnosis (PGD) or fertility preservation were compared with non-BRCA PGD or fertility preservation patients, matched by age, IVF protocol, IVF center, and cancer disease status. INTERVENTION(S): In vitro fertilization cycles for PGD and fertility preservation. MAIN OUTCOME MEASURE(S): Outcome of IVF: oocyte yield, poor response rate, number of zygotes, pregnancy rates. RESULT(S): A total of 62 BRCA mutation carriers and 62 matched noncarriers were included; 42 were fertility preservation breast cancer patients, and 82 were PGD non-cancer patients. Mean (± SD) age of patients was 32 ± 3.58 years. Number of stimulation days and total stimulation dose were comparable between carriers and noncarriers. Their cycles resulted in comparable oocyte yield (13.75 vs. 14.75) and low response rates (8.06% vs. 6.45%). Number of zygotes, fertilization rates, and conception rates were also comparable. CONCLUSION(S): Both healthy and cancer-affected BRCA mutation carriers demonstrated normal ovarian response in IVF cycles.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Fertilização in vitro , Heterozigoto , Infertilidade Feminina/terapia , Mutação , Ovário/fisiopatologia , Adulto , Análise Mutacional de DNA , Transferência Embrionária , Feminino , Preservação da Fertilidade , Triagem de Portadores Genéticos , Predisposição Genética para Doença , Humanos , Infertilidade Feminina/diagnóstico , Infertilidade Feminina/genética , Infertilidade Feminina/fisiopatologia , Israel , Recuperação de Oócitos , Fenótipo , Valor Preditivo dos Testes , Gravidez , Taxa de Gravidez , Diagnóstico Pré-Implantação , Estudos Retrospectivos , Fatores de Risco , Centros de Atenção Terciária , Resultado do Tratamento
9.
Gynecol Endocrinol ; 31(10): 779-82, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26291805

RESUMO

Oocyte cryopreservation for age-related fertility loss is gaining interest considering the tendency to postpone motherhood in many societies. Little is currently known about the actual efficiency of this approach. We aimed to explore ovarian response of presumably fertile women undergoing in vitro fertilization for this indication. A total of 105 women underwent 151 stimulation cycles at mean age 37.7 ± 2.4. None had known infertility. Mean daily starting FSH dose was 371 ± 110 (225-600). Mean number of mature oocytes cryopreserved at the first completed cycle was 9.7 ± 7.5 (0-43). However, 21% of started cycles were either cancelled before egg retrieval or resulted in 0-3 mature oocytes retrieved. Therefore, women considering oocyte cryopreservation for prevention of age-related fertility decline should be encouraged to perform this procedure at younger age than, preferably before 35.


Assuntos
Infertilidade Feminina/prevenção & controle , Recuperação de Oócitos , Oócitos/citologia , Indução da Ovulação/métodos , Adulto , Criopreservação , Feminino , Hormônio Foliculoestimulante/administração & dosagem , Humanos , Estudos Retrospectivos , Resultado do Tratamento
10.
Biomed Res Int ; 2014: 135416, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25013756

RESUMO

Congenital cytomegalovirus (CMV) is the leading infectious cause of sensorineural hearing loss and delayed psychomotor development. Viral transmission to the fetus is far more likely to occur following a primary than a secondary maternal infection. Primary prevention seems to be the best means to reduce the burden of congenital CMV due to the lack of treatment options during pregnancy. We evaluated this approach on a cohort of 500 women planning pregnancy who attended our fertility clinic. Of the 444 who underwent CMV screening, 18 (4.1%) had positive IgM serology for CMV; of these, IgG avidity was high in 12 (remote infection) and low in 6 (recent infection). The latter were advised to delay pregnancy. All women who were seroimmune for CMV (366/444, 82.4%), including the 12 with remote infection, continued fertility treatment. The remaining patients (72/444, 16.2%), who were not immune to CMV at the initial screen, were advised to minimize CMV exposure by improving personal hygiene and to continue fertility treatment. None of the 69/72 (95.8%) women who were followed for one year were infected with CMV. Cytomegalovirus testing and counselling at preconception seemed effective in reducing CMV exposure in pregnancy.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Citomegalovirus/sangue , Citomegalovirus/isolamento & purificação , Diagnóstico Pré-Natal , Adulto , Citomegalovirus/imunologia , Citomegalovirus/patogenicidade , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , Feminino , Feto/imunologia , Feto/virologia , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/virologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Gravidez , Transtornos Psicomotores/diagnóstico , Transtornos Psicomotores/virologia
11.
Eur J Obstet Gynecol Reprod Biol ; 176: 163-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24630573

RESUMO

OBJECTIVE: To determine whether the decrease in AMH levels during ovarian hyperstimulation for IVF occurs in patients with polycystic ovary syndrome (PCOS) and patients with low ovarian reserve (LOR), as in normal cycling women. STUDY DESIGN: A cohort of 22 infertile patients treated in a single tertiary center with a GnRH-antagonist short protocol for IVF were prospectively included and divided into three groups: PCOS with hyperandrogenism (n=7), LOR (n=8) and control (n=7). Serum AMH levels were measured before and during FSH treatment, on the day of HCG administration, at the mid-luteal phase, and 14 days after embryo transfer. The three groups were compared using an ANOVA model in the case of continuous data and with Fisher's exact test when the data were discrete. RESULTS: In the PCOS group, AMH levels increased at the beginning of the stimulation, but later decreased, until the mid-luteal stage. In the other two groups, AMH levels decreased throughout ovarian stimulation until the mid-luteal stage. In all groups, AMH levels returned to baseline levels two weeks after HCG administration, regardless of treatment outcome (pregnancy or not). CONCLUSIONS: AMH levels decline during controlled ovarian hyperstimulation with a GnRH-antagonist short protocol in women with low and normal ovarian reserves. In contrast, in women with PCOS, an increase in AMH levels precedes this decline. These findings may support the hypothesis that androgens may play a role in AMH regulation in women.


Assuntos
Hormônio Antimülleriano/sangue , Infertilidade Feminina/terapia , Indução da Ovulação/métodos , Síndrome do Ovário Policístico/sangue , Adulto , Hormônio Antimülleriano/metabolismo , Feminino , Fertilização in vitro/métodos , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Humanos , Hiperandrogenismo , Fase Luteal , Folículo Ovariano , Reserva Ovariana
12.
Appl Opt ; 53(4): 577-87, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24514174

RESUMO

Optical rotation (OR) polarimeters measure only the OR of a linearly polarized wave vector caused by the optical activity of the measured material. Such polarimeters are used to detect optically active materials and measure their concentration. Here we describe a novel type of high-resolution OR polarimeter. The new polarimeter is a compact device, based on a combination of two novel mechanisms: a referencing mechanism and an optical signal-gain mechanism. The patented referencing mechanism allows accurate measurements of small ORs in the presence of considerable polarization noise. The current limit of detection of the polarimeter is ∼20 micro-degrees, which we believe can be lowered further. The polarimeter is intended to serve as an add-on detector for existing high-pressure liquid chromatography (HPLC) systems in the pharmaceutical industry. The need for such a polarimeter, its optical setup, analysis of its performance, and experimental results are hereby given and discussed.

13.
Obstet Gynecol ; 122(3): 532-6, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23921856

RESUMO

Field hospitals were deployed by the Israel Defense Forces as part of the international relief efforts after major seismic events, one in Haiti (2010) and one in Japan (2011). The teams treated a total of 44 pregnant and 24 nonpregnant women and performed 16 deliveries and three cesarean deliveries under extreme conditions. Half of all deliveries were complicated by preeclampsia and 31% were preterm (at 30-32 weeks of gestation). It is imperative that obstetrician-gynecologists be included among humanitarian aid delegations sent to sites of natural disasters. The complicated cases we encountered required highly skilled obstetricians and led to a shortage of specific medications for these women. Cases that would have been considered routine under normal conditions created unanticipated ethical and practical issues in the face of very limited resources. The aim of this commentary is to share the experiences and lessons learned by our field hospital obstetrics and gynecology teams after the major earthquakes in Haiti and Japan. We present what we consider to be the 10 most important lessons learned and propose that they serve as guidelines in preparing for essential needs in other natural disaster settings.


Assuntos
Desastres , Unidades Móveis de Saúde , Obstetrícia , Complicações na Gravidez , Parto Obstétrico/estatística & dados numéricos , Feminino , Ginecologia , Humanos , Recém-Nascido , Masculino , Gravidez
14.
Gen Comp Endocrinol ; 159(2-3): 208-13, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18789943

RESUMO

In this study, the involvement of the cytochrome P450 aromatase gene (CYP19) in the gametogenesis of the teleost blue gourami (Trichogaster trichopterus) is described. The blue gourami brain CYP19 (bgCYP19b) and gonadal CYP19 (bgCYP19a) aromatase genes were cloned and their expression analyzed during the different reproductive stages. The cloned cDNAs of the bgCYP19b and bgCYP19a were found to contain segments of 1518 bp (an open reading frame encoding a deduced protein of 506 residues) and 489 bp (encoding a peptide of 163 residues), respectively. Although the mRNA levels of bgCYP19b were very low in females until the vitellogenic phase, they were significantly higher in the final oocyte maturation stage. The aromatase gene mRNA levels in the gonads were significantly lower in females in the high vitellogenic stage, as compared to females during early vitellogenesis or maturation. In males, the mRNA levels of bgCYP19b were significantly lower in juveniles than in mature individuals. However, no significant differences were observed between mature non-reproductive and reproductive males. In addition, there was no significant difference between the expression of bgCYP19a in juvenile and non-nest building mature males, although a significant increase was detected in mature reproductive males. Although CYP19b expression was similar in both sexes, the expression of CYP19a was significantly different between males and females.


Assuntos
Aromatase/metabolismo , Regulação Enzimológica da Expressão Gênica/fisiologia , Perciformes/metabolismo , Reprodução/fisiologia , Animais , Aromatase/genética , Feminino , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Isoenzimas , Masculino , Ovário/citologia , Ovário/crescimento & desenvolvimento , Perciformes/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Caracteres Sexuais , Distribuição Tecidual
15.
Gen Comp Endocrinol ; 148(3): 359-67, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16750531

RESUMO

Sturgeons are known throughout the world as the source of black caviar. Their declining populations in their native habitats, mainly the Caspian Sea, due to over-fishing for meat and caviar production, destruction of their spawning grounds and water pollution, have led to their introduction into aquaculture in areas with suitable conditions, including Israel. Recently, we noticed an unusual phenomenon in these normally gonochoristic species. Several 5-year-old female sturgeons were found to have one or more testicular sections in each of their two gonads, forming an intersexual gender. Further examination of other fish from the same age group revealed 14% fish with intersex gonads among a population of 5000 fish that had been pre-selected as females. This phenomenon has not been found however in other age groups of Russian sturgeons, cultured at the same facility. Sturgeons are a generally gonochoristic species, and hermaphroditism is only very infrequently observed under natural or normal breeding conditions. Moreover, these rare cases have all been from polluted habitats. The present work is the first description of fish containing intersex gonads in Russian sturgeon (Acipenser gueldenstaedtii). We describe the phenomenon anatomically and histologically, and examine plasma steroid levels and pituitary gonadotropin gene expression by comparing fish with intersex gonads with normal females and males of the same age group. Intersex gonads were typical female ovaries with one or more white testicular components embedded in each. The testis components were not uniform in size or location among the two gonads of each fish or among different fish, and they showed marked differences in distribution. The ovarian component of the intersex gonad was at the pre-vitellogenic stage as in normal females, and the testis component contained spermatids and mature spermatozoa as in normal males of the same age. However, in terms of estradiol and 11-ketotestosterone plasma levels, as well as of pituitary gonadotropin (betaLH and betaFSH) gene-expression levels, the fish with intersex gonads were more similar to the normal males than to the normal females, even though the testis part of the intersex gonad was smaller than the ovarian part. To examine the possibility that the fish containing intersex gonads were hybrids, phylogenetic trees were constructed from the consensus sequences of Cytochrome b and control region (D-loop) genes. Results indicated no differences between the fish with intersex gonads and normal males or females of the same age group. However, statistically significant differences were found between different age groups of Russian sturgeon, as well as of white sturgeons (A. transmontanus), grown under the same culture conditions.


Assuntos
Peixes/anatomia & histologia , Gônadas/anatomia & histologia , Gônadas/citologia , Hormônios/análise , Animais , Transtornos do Desenvolvimento Sexual/genética , Evolução Molecular , Feminino , Peixes/genética , Peixes/fisiologia , Subunidade beta do Hormônio Folículoestimulante/metabolismo , Hormônio Luteinizante Subunidade beta/metabolismo , Masculino , Ovário/citologia , Ovário/crescimento & desenvolvimento , Filogenia , Esteroides/sangue , Testículo/citologia
16.
Gen Comp Endocrinol ; 140(1): 61-73, 2005 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-15596072

RESUMO

The Russian sturgeon, Acipenser gueldenstaedtii, is a late-maturing Acipenseriformes. To elucidate the role of FSH and LH in its reproduction, we cloned its glycoprotein alpha-subunit (GPalpha) and gonadotropin beta-subunits (FSHbeta and LHbeta) using 5' and 3' RACE-PCR. The nucleotide sequences of the Russian sturgeon (st) GPalpha, FSHbeta, and LHbeta are 345, 384, and 411 bp long, encoding peptides of 91, 115, and 114 amino acids, respectively. The deduced amino acid sequence of each mature subunit showed high similarity with those of other teleosts. Sequence analysis showed that stFSHbeta is more similar to higher vertebrate FSHbetas (35-37%) than to higher vertebrate LHbetas (26-30%). The next objective of this work was to compare the development of sturgeon gonads at the very first stages of their growth with the expression of their gonadotropins. Sturgeons at ages 1, 2, 3 or 4 years were sacrificed. The expression of their gonadotropin beta-subunits was determined using quantitative real-time PCR, and their gonads were examined histologically, followed by a determination of the plasma levels of estradiol in females and 11-ketotestosterone (11-KT) in males. The expression levels of stFSHbeta subunit was found to be higher in fish at 3 and 4 years of age than in 1-year olds. mRNA levels of stLHbeta were higher than those of stFSHbeta in both genders. Moreover mRNA levels of stFSHbeta detected in females were significantly higher than those found in males. Even at age 4 years, all female Russian sturgeons tested contained gonads at the pre-vitellogenic stage, with small oocytes and very low levels of estradiol in the plasma. However, among the males, at ages 3 and 4 years, we found testes that contained spermatids and spermatozoa. Those males were found to have significantly high GSI (gonadosomatic index; gonadal weight as a percentage of BW) levels, stLHbeta expression and 11-KT levels.


Assuntos
Peixes/genética , Peixes/fisiologia , Subunidade beta do Hormônio Folículoestimulante/genética , Perfilação da Expressão Gênica , Glicoproteínas/genética , Hormônio Luteinizante Subunidade beta/genética , Ovário/crescimento & desenvolvimento , Ovário/fisiologia , Testículo/crescimento & desenvolvimento , Testículo/fisiologia , Sequência de Aminoácidos , Animais , Clonagem Molecular , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Testosterona/sangue , Testosterona/farmacologia
17.
Zoolog Sci ; 20(6): 737-43, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12832825

RESUMO

The relationship between gonadal development (histological evidence for spermiogenesis and/or spermatogenesis), sexual behavior (nest-building) and mRNA levels of gonadotropins (betaFSH and betaLH) and growth hormone (GH) in the male pituitary was investigated. Amplification of betaFSH cDNA showed a significantly higher mRNA level in mature males (whether sexually active or not) than in juveniles. However, following PCR amplification of betaLH cDNA, a significantly higher mRNA level was found in the sexually active group compared to the sexually inactive group. These results suggest that FSH may participate in spermatogenesis, whereas LH is more involved in spermiogenesis. The GH mRNA level increased slightly during the maturation process but no significant differences were found between the groups studied.


Assuntos
Subunidade beta do Hormônio Folículoestimulante/biossíntese , Regulação da Expressão Gênica , Hormônio do Crescimento/biossíntese , Hormônio Luteinizante Subunidade beta/biossíntese , Perciformes/fisiologia , Comportamento Sexual Animal , Espermatogênese/fisiologia , Animais , Primers do DNA , Subunidade beta do Hormônio Folículoestimulante/farmacologia , Hormônio do Crescimento/farmacologia , Hormônio Luteinizante Subunidade beta/farmacologia , Masculino , Reação em Cadeia da Polimerase/veterinária , RNA Mensageiro/análise , Testículo/crescimento & desenvolvimento
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