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1.
Eur Rev Med Pharmacol Sci ; 26(10): 3664-3676, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35647848

RESUMO

OBJECTIVE: Chronic pain is currently considered a disease state with biopsychosocial consequences and a negative impact on patients' quality of life (QoL). Pain from postherpetic neuralgia (PHN) can persist for months or years and is a prototypical example of chronic pain. We analyzed PHN as a model of chronic pain, including its effects on QoL and clinical aspects. We explored treatment options, focusing on the topical treatment with lidocaine 700 mg medicated plaster (LMP) and how this impacts PHN management. MATERIALS AND METHODS: This article is a narrative review of published studies. Preclinical and clinical studies were retrieved from literature through a search performed in PubMed/MEDLINE. RESULTS: To choose the appropriate treatment for chronic pains, such as PHN, not only efficacy but also tolerability, manageability, practicality, and compliance are important factors, especially in the long term. It is also important to set treatment expectations with the patients as total suppression of pain may be unrealistic, and a balance needs to be found between pain control and the minimization of adverse events. In this respect, LMP may be the best currently available treatment: it is easy to use, has low systemic absorption and thus a low risk for pharmacological interactions. Therefore, treatments can be personalized, and concomitant medications can be added, if needed. Recent data from a real-world study support this view by showing that LMP has superior effectiveness in reducing pain and improving the QoL compared to other commonly used systemic treatments and confirming its good tolerability profile that is mainly characterized by localized skin reactions. CONCLUSIONS: LMP is one of the best currently available treatment options for PHN patients balancing good efficacy with an excellent tolerability profile and can therefore be considered for use as a first-line treatment for PHN.


Assuntos
Dor Crônica , Neuralgia Pós-Herpética , Anestésicos Locais , Dor Crônica/tratamento farmacológico , Humanos , Lidocaína/uso terapêutico , Neuralgia Pós-Herpética/tratamento farmacológico , Qualidade de Vida
2.
Mol Reprod Dev ; 78(3): 161-71, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21308852

RESUMO

Our knowledge of the molecules that interact with sperm at the egg membrane is restricted to a short list. In the eggs of Discoglossus pictus, fusion with sperm is limited to a differentiated structure, the dimple, offering several advantages for detecting molecules involved in fertilization. Previous studies have identified fucosylated glycoproteins of 200, 260, and 270 kDa located at the surface of the dimple that are able to bind sperm in vitro. Here, we show that dimple glycoproteins and a protein represented by a 120-kDa band released following gel-into-gel SDS-PAGE of both glycoproteins share the same N-terminal amino acid sequence, which itself is similar to the N-termini of Xenopus liver-synthesized vitellogenin (VTG) and the lipovitellin 1. MALDI/MS mass spectrometry indicated that the 120-kDa band is part of both gps 200 and 270/260. A 117-kDa major protein of the egg lysate exhibits the same MALDI/MS spectrum, and LC-MSMS indicates that this is a lipovitellin 1 (DpLIV) that coincides with the 120-kDa band and is responsible for the formation of the 200-270-kDa dimers. Therefore, lipovitellin 1 constitutes the protein backbone of the dimple glycoconjugates. In vitro assays using polystyrene beads coated with DpLIV or with its dimers indicate that significant sperm binding occurs only with DpLIV dimers. In amphibians, VTG is taken up by the oocyte, where it releases lipovitellins destined to form yolk. In Discoglossus, our data suggest that yolk proteins are also synthesized by the oocyte. The dimple forms in the ovulated oocyte following the exocytosis of vesicles that likely expose DpLIVs at their membrane. Indeed, in whole mounts of immunostained eggs, anti-vitellogenin antibodies label only the surface of the dimple.


Assuntos
Anuros/metabolismo , Proteínas do Ovo/genética , Proteínas do Ovo/metabolismo , Interações Espermatozoide-Óvulo/fisiologia , Sequência de Aminoácidos , Animais , Anuros/fisiologia , Western Blotting , Cromatografia Líquida , Dimerização , Eletroforese em Gel de Poliacrilamida , Feminino , Imunofluorescência , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Dados de Sequência Molecular , Oócitos/ultraestrutura , Alinhamento de Sequência , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem
3.
Gen Comp Endocrinol ; 158(1): 138-44, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18602103

RESUMO

There is much concern about the increasing presence in the environment of synthetic chemicals that are able to disrupt the endocrine system. Among these compounds, 4-nonylphenol (4-NP) is one of the most studied xenoestrogens, due to its widespread accumulation in water sediment and consequent presence in fatty acid of aquatic organisms. Here, we have used a zebrafish microarray representing 16,399 genes to study the effects of 4-NP and estradiol-17beta (E2) in adult male zebrafish in order to elucidate the mechanism of action of 4-NP compared with that of E2. The microarray results showed that both 4-NP and E2 induced a strong expression of vitellogenin (VTG), the sex related precursor of the yolk proteins in oviparous vertebrates. Both treatments induced elevated protein turnover upregulating genes involved in proteolysis and those that are constituents of the ribosome. Many genes regulated by 4-NP and E2 are involved in energy metabolism, oxidative stress defense mechanisms, xenobiotic metabolism, and lipid metabolism. A different pattern of expression in the two treatments was found for genes involved in oxidative stress, since E2 seems to induce the mechanism of detoxification, while 4-NP seems to inhibit this protective mechanism of the cell. Overall, these findings demonstrate that the microarray approach can contribute significantly to the understanding of expression patterns induced by E2 and 4-NP in male zebrafish. The results also demonstrate that 4-NP is able to act through an alternative pattern to that of estradiol-17beta, modulating the expression of the same genes in a different manner.


Assuntos
Estradiol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Fenóis/farmacologia , Peixe-Zebra/genética , Animais , Disruptores Endócrinos/farmacologia , Perfilação da Expressão Gênica , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Poluentes Químicos da Água/farmacologia
4.
Mol Cell Endocrinol ; 286(1-2 Suppl 1): S52-9, 2008 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-18336994

RESUMO

Endogenous cannabinoids, through the CB1 receptor, are involved in the control of several functions including stress responses. The aim of this study was to investigate the presence of cannabinoid receptor CB1 in the sole ovary by partial cloning of brain CB1 cDNA; in a stress paradigm of disturbance by handling, which consisted in catching, netting and hand-sorting, changes of CB1 mRNA were related with those of proopiomelanocortin (POMC) mRNA; the trend and timing of stress responses and adaptation were monitored by measuring plasma cortisol levels. We characterized two forms of CB1-like receptor, termed CB1A and CB1B. The two sole CB1 (both 799bp) share 76% identity in their cDNAs, and the deduced amino acid sequences are 80% identical. The handling stress induced a sustained increase in plasma cortisol levels 1h after the handling began and decreased to low levels 12h after initiation of handling, showing the same trend of ovarian POMC mRNA expression. In addition, while CB1A mRNA did not show any significant changes during handling stress, significantly lower levels of CB1B mRNA were found in stressed fish 1h after the beginning of handling, with CB1 expression increased 24h after stress induction, both in the ovary and brain. It can be concluded that endocannabinoid system is involved in the modulation of adaptive responses to environmental conditions.


Assuntos
DNA Complementar/genética , Linguados/genética , Receptor CB1 de Canabinoide/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Feminino , Regulação da Expressão Gênica , Hidrocortisona/sangue , Dados de Sequência Molecular , Ovário/metabolismo , Pró-Opiomelanocortina/genética , Pró-Opiomelanocortina/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor CB1 de Canabinoide/química , Receptor CB1 de Canabinoide/metabolismo , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
5.
Arch Environ Contam Toxicol ; 55(2): 295-304, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18214578

RESUMO

The Tronto River (southern Marche region of central Italy) is located in an area with neighboring industrial activities and is contaminated with domestic and industrial wastewater. Water quality data analyses revealed the presence of a mixture of low levels of heavy metals and organic compounds. The effects of long-term exposure to Tronto River water on juvenile Carassius auratus were evaluated with an integrated approach using xenoestrogens biomarkers, such as vitellogenin (VTG) and ER beta-1 mRNA expression, and stress parameters (i.e., cortisol and glucose in the blood and glycogen in the liver). Treatment with Tronto River water did not induce VTG synthesis in fish and did not affect ER beta-1 mRNA expression. Moreover, cortisol titers found in the plasma of fish exposed to Tronto River water were lower than those found in the control group. Regarding energy parameters, treatment with Tronto River water induced an increase in plasma glucose and a depletion of liver glycogen reserves.The effects of Tronto River water were studied in parallel with those of 4-NP and CdCl(2). The 4-NP at the dose of 22 microg/L induced the synthesis of peripheral vitellogenin and increase of ER beta-1 titers; on the contrary, CdCl2 exposure at the concentration of 22 microg/L did not induce significant changes on plasma VTG and/or hepatic ER beta-1 levels. In addition, no significant changes in plasma cortisol levels in fish exposed to 4-NP or CdCl(2) were found. Fish exposed to CdCl(2) displayed liver glycogen depletion, but no significant increase in plasma glucose was observed. On the contrary, a 30-day exposure to 4-NP induced only a slight decrease of glycogen reserves without any changes in plasma glucose levels. In conclusion, our study demonstrated that long-term exposure of juvenile goldfish to the water of the Tronto River significantly affects both stress and energy parameters. There is evidence that pollutants, present in Tronto River water, were not able to induce xenoestrogenic effects but caused a functional impairment of the hypothalamum-pituitary-interrenal axis.


Assuntos
Biomarcadores/análise , Monitoramento Ambiental , Carpa Dourada/metabolismo , Rios/química , Poluição Química da Água/análise , Análise de Variância , Animais , Glicemia/análise , Cloreto de Cádmio/metabolismo , Ensaio de Imunoadsorção Enzimática , Receptor beta de Estrogênio/sangue , Expressão Gênica , Glicogênio/metabolismo , Hidrocortisona/sangue , Itália , Fígado/metabolismo , Fenóis/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tempo , Vitelogeninas/sangue , Xenobióticos/análise
6.
Gen Comp Endocrinol ; 155(1): 227-33, 2008 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17559851

RESUMO

Proopiomelanocortin (POMC) is an important gene implicated in different functions, such as the stress response of the hypothalamus-pituitary-adrenal axis. The aim of the present study was to determine whether farming conditions, such as stocking density, can be considered a powerful stressor influencing in turn the growth rate in juvenile fish. Thus, POMC cDNA expression was investigated during adaptation to farming conditions in sole (Solea solea), as a model for studying the effects of rearing densities on stress response; different stocking densities (50, 100, and 250 animals/m(2)) were applied and, after 7 and 21 days, the fishes were examined for body weight and plasma cortisol levels as indicators of stress. In addition, proopiomelanocortin was cloned and sequenced from the brain of sole, allowing semi-quantitative RT-PCR to be performed to evaluate POMC mRNA expression in brain tissue. There was a significant increase in cortisol levels in fish reared at high stocking densities of 250/m(2) compared to fish reared at control densities of 100 and 50/m(2), in both experimental times, i.e., 7 and 21 days. The high stocking densities were also found to decrease the specific growth rate of fish. Moreover, it was demonstrated that the highest stocking density induced a significant decrease in sole POMC mRNA expression. It is concluded that POMC and cortisol are both involved in the stress response due to high rearing densities, during which cortisol may serve as a negative regulator of POMC.


Assuntos
Aglomeração/fisiopatologia , Linguados/crescimento & desenvolvimento , Linguados/genética , Pró-Opiomelanocortina/genética , RNA Mensageiro/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Peso Corporal/fisiologia , Clonagem Molecular , DNA Complementar/isolamento & purificação , Linguados/sangue , Regulação da Expressão Gênica , Hidrocortisona/sangue , Dados de Sequência Molecular , Densidade Demográfica , Pró-Opiomelanocortina/metabolismo , Homologia de Sequência de Aminoácidos
7.
Gen Comp Endocrinol ; 150(2): 263-9, 2007 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17078952

RESUMO

Two cannabinoid receptor-like genes (CB1-like), named CB1A and CB1B, have been isolated in teleost fish, specifically in the puffer fish, Fugu rubripes. However, information on the physiological roles, such as the control of reproduction and development in fish is still scarce. Therefore, the aim of the present study was to investigate the presence of CB1-like mRNA in the gonads of a marine teleost species, the gilthead seabream, Sparus aurata, a hermaphrodite species in which the gonadal tissues first develop as testes, and then as functional ovary. We isolated an 890 bp fragment (GenBank accession number ); that corresponded to the open reading frame of the teleost CB1 receptor gene, encoding for the central portion of the protein, which was aligned with the other bony fish sequence. Using "in situ" hybridization, CB1-like mRNA was localized in both mature and sex-reversing gonads, and relative changes in CB1-like expression levels were detected through semi-quantitative RT-PCR. In the mature testis and in the testicular part of the sex-reversing gonad, CB1 expression levels were found to be much higher compared to the ovarian portion. This suggests that the CB1 signaling is likely involved in the process of testicular regression of the S. aurata, but its actual role has yet to be determined.


Assuntos
Organismos Hermafroditas , Receptor CB1 de Canabinoide/genética , Dourada/genética , Processos de Determinação Sexual , Sequência de Aminoácidos , Animais , Sequência de Bases , Feminino , Gônadas/fisiologia , Hibridização In Situ , Masculino , Dados de Sequência Molecular , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptor CB1 de Canabinoide/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Dourada/metabolismo , Alinhamento de Sequência
8.
Mol Reprod Dev ; 74(1): 57-67, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16929534

RESUMO

It has been proposed that gonadotropin-releasing hormone (GnRH) plays an autocrine/paracrine regulatory role in mammalian and fish ovaries. The marine teleost gilthead seabream is an interesting model since, during the life span of the fish, gonadal tissues develop first as testes, which then regress allowing the development of ovarian follicles. Recent studies carried out in ovaries of the gilthead seabream have demonstrated that various GnRH transcripts as well as GnRH splicing variants are expressed. The mRNA level of several GnRH forms in the female and male areas of the switching gonad, and their possible role in this process, were further investigated. The results here reported show that sGnRH, cGnRH-II, and sbGnRH transcripts are locally expressed during gilthead seabream gonadal differentiation; the expression of the three GnRH forms was found to differ among the morphologically defined areas of the switching gonad, as demonstrated by applying reverse transcription-polymerase chain reaction (RT-PCR), together with in situ hybridization, and semiquantitative PCR analyses. Moreover, the hypothesis that GnRH forms may regulate testicular regression via an apoptotic mechanism was investigated by analyzing the different areas of switching gonads for caspase-3 activity as a measure of apoptosis. Our results showed a marked increase of caspase-3 activity in the area corresponding to the regressing testes in which a significant decrease of testosterone production was also found. The present findings demonstrate that the changes in the endogenous GnRH transcripts could be related with the gonadal differentiation in gilthead seabream, and that exogenous GnRH plays a role by stimulating apoptosis in the degenerating testis.


Assuntos
Genes de Troca , Hormônio Liberador de Gonadotropina/fisiologia , Gônadas/crescimento & desenvolvimento , Dourada/crescimento & desenvolvimento , Diferenciação Sexual/genética , Processamento Alternativo , Animais , Feminino , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/farmacologia , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Masculino , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Dourada/anatomia & histologia , Dourada/genética , Testosterona/biossíntese , Transcrição Gênica
9.
J Microbiol Methods ; 64(1): 135-8, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15927289

RESUMO

One hundred strains of Stenotrophomonas maltophilia isolates from respiratory specimens were biochemically identified using the API 20NE strip and the VITEK2 ID-GNB card. The identification was confirmed by a species-specific PCR using two primers specific for the 23S rRNA gene. The API 20NE showed only 1 strain with "low discrimination" whereas the VITEK2 gave 12. In any case, the two biochemical systems showed good reliability compared to SS-PCR.


Assuntos
Técnicas Bacteriológicas/métodos , Infecções por Bactérias Gram-Negativas/epidemiologia , Stenotrophomonas maltophilia/isolamento & purificação , Brônquios/microbiologia , Fibrose Cística/microbiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Reação em Cadeia da Polimerase/métodos , Especificidade da Espécie , Escarro/microbiologia , Stenotrophomonas maltophilia/classificação , Stenotrophomonas maltophilia/genética , Traqueia/microbiologia
10.
Mol Reprod Dev ; 73(1): 1-8, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16177984

RESUMO

Proopiomelanocortin (POMC) is a precursor protein that contains the sequences of several bioactive peptides including adrenocorticotropin (ACTH), beta-endorphin (beta-EP), and melanocyte-stimulating-hormone (MSH). POMC is synthesized in the pituitary gland, brain, and many peripheral tissues. Immunoreactive POMC-derived peptides as well as POMC-like mRNA have been evidenced in several nonpituitary tissues, thus suggesting that POMC is actively synthesized by these tissues. The present study was aimed at evaluating if also in the case of stallion POMC-derived peptide, beta-EP, is produced locally in the testis, thus playing effects in a paracrine/autocrine fashion. To investigate this hypothesis the POMC gene expression was analyzed using 3' RACE-PCR and Northern Blot approaches in the testis and epididimys of stallion; moreover, immunocytochemical localization for beta-EP was also performed through confocal laser microscopy. The immunofluorescence results showed a positive beta-EP reaction not only in cellular nest of pituitary but also in the testis and genital tract of stallion, which function could be related with sperm mobility. Such role seem not to be no dependent on the peptide synthesized locally, because the molecular biology approach demonstrated the presence of POMC transcript in the pituitary only. In fact the Northern Blot analysis showed the presence of a single POMC transcript in the pituitary while no signal was detected in the testis and epididimys. The same results were obtained by applied 3' RACE-PCR analysis. In conclusion, opioid-derived peptide beta-EP is present in the genital tract of stallion, but is not locally produced as in other mammalian, and nonmammalian models; its possible biological function at testicular level could be linked to a long-loop feed-back mechanisms.


Assuntos
Epididimo/metabolismo , Cavalos/metabolismo , Hipófise/metabolismo , Pró-Opiomelanocortina/biossíntese , Pró-Opiomelanocortina/genética , Testículo/metabolismo , beta-Endorfina/metabolismo , Animais , Sequência de Bases , Northern Blotting , Humanos , Masculino , Microscopia Confocal , Microscopia de Fluorescência , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
11.
Gen Comp Endocrinol ; 142(3): 318-24, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15935158

RESUMO

Some chemical compounds used in intensive agriculture have been found to induce estrogenic effects; therefore a histological analysis of the testes and an evaluation of plasma levels of sex steroid, thyroid hormones, and vitellogenin were carried out in adult male water frogs of two coexisting taxa (Rana lessonae and the hemiclonal hybrid Rana esculenta) sampled in agricultural and pristine areas. Differences in seasonal profiles of hormones were found in water frogs living in the agricultural area where the presence of endocrine disrupting compounds was suspected on the basis of a previous study. In R. esculenta, sampled in the pristine area, high androgen levels were found in May; the opposite trend was found for R. esculenta sampled in agricultural areas in which the highest androgen levels were found in September, significantly lower compared with those found in R. esculenta sampled in the pristine area. Low androgen levels were also recorded in R. lessonae males sampled both in pristine and agricultural areas, while the highest levels were found in September. Regarding the trend of estradiol-17beta, an increase of this hormone was found in July both in esculenta and lessonae sampled in the agricultural area, and in the same month an estradiol-17beta peak, even though lower, was also found both in esculenta and lessonae males captured in the pristine area; detectable vitellogenin was found neither in males captured in the agricultural area, nor in those sampled in the pristine one. Moreover, while no significant changes of thyroid hormones were found either in the esculenta or lessonae males sampled in the pristine area, increased T3 and T4 titers were found in July in both esculenta and lessonae captured in the agricultural area. Morphological differences of the testes in males of parental species captured in the agricultural area were also observed. These findings indicate alterations in endocrine and reproductive function in frogs in the agricultural area, that could suggest the presence of endocrine disrupting compounds.


Assuntos
Agroquímicos/intoxicação , Hormônios Esteroides Gonadais/sangue , Rana esculenta/sangue , Testículo/efeitos dos fármacos , Hormônios Tireóideos/sangue , Poluentes Químicos da Água/intoxicação , Agricultura , Androgênios/sangue , Animais , Estradiol/sangue , Histocitoquímica , Itália , Masculino , Tiroxina/sangue , Tri-Iodotironina/sangue , Vitelogeninas/sangue
12.
Toxicol Appl Pharmacol ; 209(3): 236-43, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-15921715

RESUMO

Many synthetic chemicals, termed xenoestrogens, have been shown to interact as agonists with the estrogen receptor (ER) to elicit biological responses similar to those of natural hormones. To date, the regulation of vitellogenesis in oviparous vertebrates has been widely used for evaluation of estrogenic effects. Therefore, Carassius auratus juveniles were chosen as a fish model for studying the effects of estradiol-17beta and different concentrations (10(-6) and 10(-7) M) of 4-nonylphenol (4-NP) on the expression of liver ERbeta-1 subtype; plasma vitellogenin and sex steroids (androgens and estradiol-17beta) were also evaluated together with the bioaccumulation process, through mass-spectrometry. C. auratus is a species widespread in the aquatic environment and, on the toxicological point of view, can be considered a good "sentinel" species. Juveniles of goldfish were maintained in tanks with only tap water or water with different concentrations (10(-6) and 10(-7) M) of 4-nonylphenol (4-NP), or 10(-7) M of estradiol-17beta. After 3 weeks of treatment, animals were anesthetized within 5 min after capture, and blood was immediately collected into heparinized syringes by cardiac puncture and stored at -70 degrees C; the gonads were fixed, then frozen and stored at -70 degrees C; the whole fish, liver, and muscle tissues were harvested and immediately stored at -70 degrees C for molecular biology experiments and bioaccumulation measurements. The estrogenic effects of 4-NP were evidenced by the presence of plasma vitellogenin in juveniles exposed both to estradiol-17beta and the two doses of 4-NP; moreover, exposure to 4-NP also increased aromatization of androgens, as suggested by decreasing androgens and increasing estradiol-17beta plasma levels. The changes of these parameters were in agreement with the increasing transcriptional rate of ERbeta-1 mRNA in the liver, demonstrating that both estradiol-17beta and 4-NP modulate the vitellogenin rate through interaction with the ERbeta-1 subtype. The present study also suggests that 4-NP at the concentration of 10(-6) M bioaccumulates in the liver.


Assuntos
Estradiol/farmacologia , Receptor beta de Estrogênio/metabolismo , Fenóis/farmacologia , Vitelogeninas/biossíntese , Androgênios/sangue , Animais , Relação Dose-Resposta a Droga , Estradiol/sangue , Estradiol/farmacocinética , Receptor beta de Estrogênio/genética , Cromatografia Gasosa-Espectrometria de Massas , Carpa Dourada , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fenóis/sangue , Fenóis/farmacocinética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Distribuição Tecidual , Vitelogeninas/sangue
13.
Phys Rev Lett ; 94(12): 127206, 2005 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15903958

RESUMO

A novel theoretical approach to magnetization dynamics driven by spin-polarized currents is presented. Complete stability diagrams are obtained for the case where spin torques and external magnetic fields are simultaneously present. Quantitative predictions are made for the critical currents and fields inducing magnetization switching, for the amplitude and frequency of magnetization self-oscillations, and for the conditions leading to hysteretic transitions between self-oscillations and stationary states.

14.
Ann N Y Acad Sci ; 1040: 261-3, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15891038

RESUMO

Proopiomelanocortin (POMC) is the precursor protein of different hormones and neuropeptides, and the POMC-derived peptides are produced through proteolytic cleavage. Prohormone convertase PC1 and PC2 are enzymes responsible for the cleavage of the POMC prohormone. The coexpression of POMC, PC1, and PC2 genes was previously described in the brain and the pituitary gland of Rana esculenta and Xenopus laevis, but no data are available for the gonad. The present work demonstrates a gonadal POMC convertase gene expression in Rana esculenta and Xenopus laevis.


Assuntos
Ovário/metabolismo , Pró-Opiomelanocortina/biossíntese , Pró-Proteína Convertase 1/genética , Pró-Proteína Convertase 2/genética , Rana esculenta/metabolismo , Testículo/metabolismo , Xenopus laevis/metabolismo , Animais , Feminino , Gônadas/metabolismo , Masculino , Pró-Opiomelanocortina/genética , Pró-Proteína Convertase 1/biossíntese , Pró-Proteína Convertase 2/biossíntese , Rana esculenta/genética , Xenopus laevis/genética
15.
G Chir ; 24(8-9): 312-4, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-14664190

RESUMO

The target of this study is the evaluation of two different noninvasive tests: 13C-urea Breath-Test, as gold standard, versus the HpSA test, as new method to research the faecal antigen of Helicobacter Pylori (HP). Thirty patients, affected by dyspeptic symptomatology and never treated before by antibiotic therapy to eradicate the HP, was subjected, by Authors, to this evaluation. This study say that the 13C-urea Breath-test represent the gold standard in the pre-endoscopic research of HP presence concerning specificity and sensibility. However, the HpSA test need more improvement.


Assuntos
Antígenos de Bactérias/análise , Testes Respiratórios , Fezes/química , Helicobacter pylori/imunologia , Isótopos de Carbono , Humanos , Sensibilidade e Especificidade
16.
Mol Reprod Dev ; 66(3): 291-6, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14502608

RESUMO

In the present study, the sea-bream Sparus aurata, a pelagic egg spawner, was used as experimental model, in order to establish the occurrence of apoptosis in vertebrates with external reproduction. The same female ovulates floating and nonfloating eggs, but only the former, after fertilization, proceed to embryo development. The eggs were divided into floating and nonfloating and both were analyzed for the presence of several apoptosis markers. The results here reported provide evidence that the nonfloating cells present severe shrinkage and highly express both FAS receptor and FAS ligand on their surface. Furthermore, DNA fragmentation and mitochondria swelling were found, suggesting that the nonfloating eggs were cells programmed to die.


Assuntos
Apoptose/fisiologia , Oócitos/fisiologia , Folículo Ovariano/metabolismo , Óvulo/fisiologia , Dourada/fisiologia , Animais , Fragmentação do DNA , Proteína Ligante Fas , Feminino , Glicoproteínas de Membrana/metabolismo , Mitocôndrias/patologia , Folículo Ovariano/citologia , Óvulo/ultraestrutura , Proteínas/metabolismo , Dourada/anatomia & histologia , Receptor fas/metabolismo
17.
Gen Comp Endocrinol ; 132(3): 391-8, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12849962

RESUMO

The possible effect of proopiomelanocortin-derived peptide, beta-endorphin on frog gonadotrope cells was investigated. Binding and internalization of beta-endorphin to pituitary pars distalis cultured cells were visualized by immunofluorescence and analyzed by means of confocal laser scanning microscopy. Using biotinylated endorphin, the time-course of beta-binding showed that this opioid was internalized through receptor-mediated endocytosis, the mechanism in which actin and clathrin were involved; then, the lysosomal degradation program occurred at later stages. The beta-endorphin binding was well antagonized by Naloxone, the opiate receptor antagonist, and up-regulated since more rapid response was obtained in the previously primed cells. The double immunostaining reaction for beta-endorphin and LH beta-subunit revealed that half the beta-endorphin labeled cell population was positively immunostained for LH beta-subunit, and beta-endorphin was able to induce an increasing trend of LH secretion in cultured pars distalis cells. Therefore, it seems that beta-endorphin acts directly on pituitary pars distalis and influences gonadotropin secretion through the interaction with its own receptor.


Assuntos
Hormônio Luteinizante/metabolismo , Hipófise/metabolismo , Rana esculenta/metabolismo , beta-Endorfina/metabolismo , Actinas/metabolismo , Análise de Variância , Animais , Sítios de Ligação , Clatrina/metabolismo , Imunofluorescência , Técnicas In Vitro , Masculino , Hipófise/citologia , Fatores de Tempo
19.
Am J Physiol Cell Physiol ; 283(3): C673-8, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12176724

RESUMO

Experiments were carried out to study in vitro the effects of 17beta-estradiol (E(2)), homologous pituitary homogenate (HPH), and recombinant red sea bream growth hormone (sbGH) on vitellogenin (VTG) secretion from cultured sea bream liver fragments. Basal secretion of VTG was found to be significantly higher in the prespawning period, compared with sea bream liver in the spawning and postspawning periods. Similarly, the sea bream liver obtained during the prespawning period responded more significantly to treatments with E(2), HPH, or sbGH compared with sea bream liver during spawning. In the postspawning period, treatments with E(2), HPH, or sbGH were without significant effect on VTG secretion level in sea bream liver. The level of E(2) receptors was also analyzed by Western blot analysis. The result demonstrates a significantly higher level of E(2) receptors in the sea bream liver at the prespawning stage compared with those at the spawning and postspawning stages. The findings support the hypothesis that homologous upregulation of estrogen receptors plays an important role in the estrogen-sensitive control of VTG synthesis in the sea bream liver.


Assuntos
Hormônios/fisiologia , Fígado/metabolismo , Vitelogeninas/biossíntese , Animais , Western Blotting , Linhagem Celular , Meios de Cultivo Condicionados/química , Estradiol/farmacologia , Feminino , Hormônio do Crescimento/farmacologia , Hormônios/farmacologia , Humanos , Técnicas In Vitro , Fígado/efeitos dos fármacos , Hipófise/química , Hormônios Hipofisários/farmacologia , Receptores de Estradiol/análise , Receptores de Estradiol/metabolismo , Proteínas Recombinantes/farmacologia , Dourada , Estações do Ano , Extratos de Tecidos/farmacologia
20.
Gen Comp Endocrinol ; 126(2): 125-9, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12030767

RESUMO

In this paper, the effects of an estrogenic compound, 4-nonyl-phenol (NP), on the amphibians Rana esculenta and Triturus carnifex are described together with those on sexual differentiation in Xenopus laevis. NP increased plasma vitellogenin in male frogs and newts in a dose-related manner; moreover, inhibitory effects on gonadotropin and prolactin (PRL) secretion by pituitary were found together with an elevation of plasma androgens. NP treatment also caused a remarkable increase in number of prolactin-immunolabeled cells, suggesting that xenoestrogen might induce, at least in the newt pituitary, a PRL accumulation possibly due to a reduction of the hormone release. In addition, both NP and bisphenol A caused feminization by increasing the percentage of female phenotypes in X. laevis, and the in vivo effects were more pronounced than those of estradiol-17beta.


Assuntos
Anfíbios/fisiologia , Exposição Ambiental , Estrogênios não Esteroides/farmacologia , Fenóis/farmacologia , Animais , Aromatase/metabolismo , Feminino , Hormônios Esteroides Gonadais/sangue , Gonadotropinas/metabolismo , Hipotálamo/enzimologia , Masculino , Prolactina/metabolismo , Rana esculenta/fisiologia , Reprodução , Diferenciação Sexual/efeitos dos fármacos , Triturus/fisiologia , Vitelogeninas/sangue , Xenopus laevis/fisiologia
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