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1.
Front Neuroendocrinol ; 48: 58-69, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28739507

RESUMO

Important complications of diabetes mellitus in the nervous system are represented by diabetic peripheral neuropathy and diabetic encephalopathy. In this context, an important link is represented by neuroactive steroids (i.e., steroids coming from peripheral glands and affecting nervous functionality as well as directly synthesized in the nervous system). Indeed, diabetes does not only affect the reproductive axis and consequently the levels of sex steroid hormones, but also those of neuroactive steroids. Indeed, as will be here summarized, the levels of these neuromodulators present in the central and peripheral nervous system are affected by the pathology in a sex-dimorphic way. In addition, some of these neuroactive steroids, such as the metabolites of progesterone or testosterone, as well as pharmacological tools able to increase their levels have been demonstrated, in experimental models, to be promising protective agents against diabetic peripheral neuropathy and diabetic encephalopathy.


Assuntos
Encefalopatias/metabolismo , Complicações do Diabetes/metabolismo , Neuropatias Diabéticas/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Bainha de Mielina/metabolismo , Neuropeptídeos/metabolismo , Caracteres Sexuais , Animais , Encefalopatias/etiologia , Complicações do Diabetes/complicações , Feminino , Humanos , Masculino
2.
Bioinformatics ; 33(11): 1730-1732, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28130230

RESUMO

SUMMARY: Shotgun metagenomics by high-throughput sequencing may allow deep and accurate characterization of host-associated total microbiomes, including bacteria, viruses, protists and fungi. However, the analysis of such sequencing data is still extremely challenging in terms of both overall accuracy and computational efficiency, and current methodologies show substantial variability in misclassification rate and resolution at lower taxonomic ranks or are limited to specific life domains (e.g. only bacteria). We present here MetaShot, a workflow for assessing the total microbiome composition from host-associated shotgun sequence data, and show its overall optimal accuracy performance by analyzing both simulated and real datasets. AVAILABILITY AND IMPLEMENTATION: https://github.com/bfosso/MetaShot. CONTACT: graziano.pesole@uniba.it. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Metagenômica/métodos , Microbiota/genética , Software , Algoritmos , Bactérias/classificação , Bactérias/genética , Fungos/classificação , Fungos/genética , Humanos , Análise de Sequência de DNA/métodos , Vírus/classificação , Vírus/genética , Fluxo de Trabalho
3.
Environ Pollut ; 344: 123316, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38185358

RESUMO

This study presents the mineralogy and strontium isotope ratio (87Sr/86Sr) of 21 pathological biominerals (bladder and kidney stones) collected from patients admitted between 2018 and 2020 at the Department of Urology of the San Pio Hospital (Benevento, southern Italy). Urinary stones belong to the calcium oxalate, purine or calcium phosphate mineralogy types. Their corresponding 87Sr/86Sr range from 0.707607 for an uricite sample to 0.709970 for a weddellite one, and seem to be partly discriminated based on the mineralogy. The comparison with the isotope characteristics of 38 representative Italian bottled and tap drinking waters show a general overlap in 87Sr/86Sr with the biominerals. However, on a smaller geographic area (Campania Region), we observe small 87Sr/86Sr differences between the biominerals and local waters. This may be explained by external Sr inputs for example from agriculture practices, inhaled aerosols (i.e., particulate matter), animal manure and sewage, non-regional foods. Nevertheless, biominerals of patients that stated to drink and eat local water/wines and foods every day exhibited a narrower 87Sr/86Sr range roughly matching the typical isotope ratios of local geological materials and waters, as well as those of archaeological biominerals from the same area. Finally, we conclude that the strontium isotope signature of urinary stones may reflect that of the environmental matrices surrounding patients, but future investigations are recommended to ultimately establish the potential for pathological biominerals as reliable biomonitoring proxies, taking into the account the contribution of the external sources of Sr.


Assuntos
Água Potável , Cálculos Urinários , Animais , Humanos , Isótopos de Estrôncio/análise , Isótopos , Agricultura , Estrôncio
4.
Bioinformatics ; 24(10): 1300-4, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18388144

RESUMO

MOTIVATION: Alternative splicing has recently emerged as a key mechanism responsible for the expansion of transcriptome and proteome complexity in human and other organisms. Although several online resources devoted to alternative splicing analysis are available they may suffer from limitations related both to the computational methodologies adopted and to the extent of the annotations they provide that prevent the full exploitation of the available data. Furthermore, current resources provide limited query and download facilities. RESULTS: ASPicDB is a database designed to provide access to reliable annotations of the alternative splicing pattern of human genes and to the functional annotation of predicted splicing isoforms. Splice-site detection and full-length transcript modeling have been carried out by a genome-wide application of the ASPic algorithm, based on the multiple alignments of gene-related transcripts (typically a Unigene cluster) to the genomic sequence, a strategy that greatly improves prediction accuracy compared to methods based on independent and progressive alignments. Enhanced query and download facilities for annotations and sequences allow users to select and extract specific sets of data related to genes, transcripts and introns fulfilling a combination of user-defined criteria. Several tabular and graphical views of the results are presented, providing a comprehensive assessment of the functional implication of alternative splicing in the gene set under investigation. ASPicDB, which is regularly updated on a monthly basis, also includes information on tissue-specific splicing patterns of normal and cancer cells, based on available EST sequences and their library source annotation. AVAILABILITY: www.caspur.it/ASPicDB


Assuntos
Mapeamento Cromossômico/métodos , Sistemas de Gerenciamento de Base de Dados , Bases de Dados Genéticas , Sítios de Splice de RNA/genética , Alinhamento de Sequência/métodos , Análise de Sequência de DNA/métodos , Interface Usuário-Computador , Sequência de Bases , Gráficos por Computador , Armazenamento e Recuperação da Informação/métodos , Dados de Sequência Molecular
5.
J Cell Biol ; 148(5): 1021-34, 2000 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-10704451

RESUMO

We show that normal peripheral nerve myelination depends on strict dosage of the most abundantly expressed myelin gene, myelin protein zero (Mpz). Transgenic mice containing extra copies of Mpz manifested a dose-dependent, dysmyelinating neuropathy, ranging from transient perinatal hypomyelination to arrested myelination and impaired sorting of axons by Schwann cells. Myelination was restored by breeding the transgene into the Mpz-null background, demonstrating that dysmyelination does not result from a structural alteration or Schwann cell-extrinsic effect of the transgenic P(0) glycoprotein. Mpz mRNA overexpression ranged from 30-700%, whereas an increased level of P(0) protein was detected only in nerves of low copy-number animals. Breeding experiments placed the threshold for dysmyelination between 30 and 80% Mpz overexpression. These data reveal new points in nerve development at which Schwann cells are susceptible to increased gene dosage, and suggest a novel basis for hereditary neuropathy.


Assuntos
Doenças Desmielinizantes/congênito , Dosagem de Genes , Proteína P0 da Mielina/biossíntese , Proteína P0 da Mielina/genética , Doenças do Sistema Nervoso Periférico/congênito , Animais , Western Blotting , Doenças Desmielinizantes/genética , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/patologia , Regulação da Expressão Gênica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Proteína Básica da Mielina/biossíntese , Proteína Básica da Mielina/genética , Proteínas da Mielina/biossíntese , Proteínas da Mielina/genética , Especificidade de Órgãos , Doenças do Sistema Nervoso Periférico/genética , Doenças do Sistema Nervoso Periférico/metabolismo , Doenças do Sistema Nervoso Periférico/patologia , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células de Schwann/metabolismo , Células de Schwann/ultraestrutura , Nervo Isquiático/metabolismo , Nervo Isquiático/ultraestrutura
6.
J Neurol ; 266(11): 2629-2645, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31278453

RESUMO

Mutations of myelin protein zero gene (MPZ) are found in 5% of Charcot-Marie-Tooth patients. In 2004, Shy et al. identified two main phenotypes associated with them: an early-onset subtype with mainly demyelinating features and a late-onset subgroup with prominent axonal impairment. We evaluated whether novel MPZ mutations described in literature during the last 14 years could still fit with this classification. We collected and revised reports of 69 novel MPZ mutations. Almost 90% of them could be alternatively classified as responsible for: (a) an early-onset phenotype, with first limitations starting before 3 years (2.5 ± 0.50 years), motor milestones delays, frequently severe course and upper limb MNCVs below 15 m/s; (b) late-onset neuropathy, with mean age of onset of 42.8 ± 1.5 years and mean upper limbs motor nerve conduction velocities (MNCVs) of 47.2 ± 1.4 m/s; (c) a phenotype more similar to typical CMT1A neuropathy, with onset during the 2nd decade, MNCV in the range of 15-30 m/s and slowly progressive course. The present work confirms that P0-related neuropathies may be separated into two main distinct phenotypes, while a third, relatively small, group comprehend patients carrying MPZ mutations and a childhood-onset disease, substantiating the subdivision into three groups proposed by Sanmaneechai et al. (Brain 138:3180-3192, 2015). Interestingly, during the last years, an increasing number of novel MPZ mutations causing a late-onset phenotype has been described, highlighting the clinical relevance of late-onset P0 neuropathies. Since the family history for neuropathy is often uncertain, due to the late disease onset, the number of patients carrying this genotype is probably underestimated.


Assuntos
Doença de Charcot-Marie-Tooth/genética , Proteína P0 da Mielina/genética , Idade de Início , Humanos , Mutação , Fenótipo
7.
Sci Rep ; 8(1): 8229, 2018 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-29844430

RESUMO

We analyze a wide gravity low in the Campania Active Volcanic Area and interpret it by a large and deep source distribution of partially molten, low-density material from about 8 to 30 km depth. Given the complex spatial-temporal distribution of explosive volcanism in the area, we model the gravity data consistently with several volcanological and petrological constraints. We propose two possible models: one accounts for the coexistence, within the lower/intermediate crust, of large amounts of melts and cumulates besides country rocks. It implies a layered distribution of densities and, thus, a variation with depth of percentages of silicate liquids, cumulates and country rocks. The other reflects a fractal density distribution, based on the scaling exponent estimated from the gravity data. According to this model, the gravity low would be related to a distribution of melt pockets within solid rocks. Both density distributions account for the available volcanological and seismic constraints and can be considered as end-members of possible models compatible with gravity data. Such results agree with the general views about the roots of large areas of ignimbritic volcanism worldwide. Given the prolonged history of magmatism in the Campania area since Pliocene times, we interpret the detected low-density body as a developing batholith.

8.
Cell Death Dis ; 6: e1663, 2015 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-25719247

RESUMO

Mitochondrial fission and fusion are essential processes in the maintenance of the skeletal muscle function. The contribution of these processes to muscle development has not been properly investigated in vivo because of the early lethality of the models generated so far. To define the role of mitochondrial fission in muscle development and repair, we have generated a transgenic mouse line that overexpresses the fission-inducing protein Drp1 specifically in skeletal muscle. These mice displayed a drastic impairment in postnatal muscle growth, with reorganisation of the mitochondrial network and reduction of mtDNA quantity, without the deficiency of mitochondrial bioenergetics. Importantly we found that Drp1 overexpression activates the stress-induced PKR/eIF2α/Fgf21 pathway thus leading to an attenuated protein synthesis and downregulation of the growth hormone pathway. These results reveal for the first time how mitochondrial network dynamics influence muscle growth and shed light on aspects of muscle physiology relevant in human muscle pathologies.


Assuntos
Dinaminas/metabolismo , Músculo Esquelético/metabolismo , Animais , Western Blotting , DNA Mitocondrial/metabolismo , Dinaminas/genética , Imunoprecipitação , Potencial da Membrana Mitocondrial/genética , Potencial da Membrana Mitocondrial/fisiologia , Camundongos , Camundongos Transgênicos , Consumo de Oxigênio/fisiologia
9.
Adv Drug Deliv Rev ; 55(10): 1279-91, 2003 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-14499707

RESUMO

Synthetically produced GRF1-29 (Sermorelin) has an amino acid composition identical to the N-terminal 29 amino acids sequence of the natural hypothalamic GHRH1-44 (Figure 1). It maintains bioactivity in vitro and is almost equally effective in eliciting secretion of endogenous growth hormone in vivo. The main drawbacks associated with the pharmaceutical use of hGRF1-29 relate to its short half-life in plasma, about 10-20 min in humans, which is caused mostly by renal ultrafiltration and enzymatic degradation at the N terminus. PEGylation has been considered as one valid approach to obtain more stable forms of the peptide, with a longer in vivo half-life and ultimately with increased pharmacodynamic response along the somatotropic axis (endogenous GH, IGF-1 levels). Different PEGylated GRF conjugates were obtained and their bioactivity was tested in vitro and in vivo by monitoring endogenous growth hormone (GH) serum levels after intravenous (i.v.) injection in rats, and intravenous and subcutaneous (s.c.) injection in pigs. It was found that GRF-PEG conjugates are able to bind and activate the human GRF receptor, although with different potency. The effect of PEG molecular weight, number of PEG chains bound and position of PEGylation site on GRF activity were investigated. Mono-PEGylated isomers with a PEG5000 polymer chain linked to Lys 12 or Lys 21 residues, showed high biological activity in vitro, which is similar to that of hGRF1-29, and a higher pharmacodynamic response as compared to unmodified GRF molecule.


Assuntos
Polietilenoglicóis/farmacologia , Sermorelina , Animais , Área Sob a Curva , Disponibilidade Biológica , Meia-Vida , Humanos , Sermorelina/análogos & derivados , Sermorelina/metabolismo , Sermorelina/farmacocinética , Sermorelina/farmacologia , Relação Estrutura-Atividade
10.
J Endocrinol ; 137(1): 49-57, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8492076

RESUMO

The presence and activity of brain, pituitary and testicular beta-endorphin (beta-EP)-like material have been studied in the frog, Rana esculenta, using reverse-phase high-pressure liquid chromatography, coupled with radioimmunoassay and immunocytochemistry. In-vivo and in-vitro treatments with naltrexone were carried out to assess the putative physiological activity of opioid peptides. beta-EP(1-31) and (1-27), together with their acetylated forms, have been identified in brain, pituitary and testis. In particular, beta-EP(1-31) concentrations peaked during July in the brain and pituitary, whilst in testes maximum concentrations were found in April and November. beta-EP immunoreactivity was present in the brain within the nucleus preopticus and nucleus infundibularis ventralis while positive fibres in the retrochiasmatic regions projected to the median eminence. In the testis, interstitial cells, canaliculi of the efferent system, spermatogonia and spermatocytes showed positive immunostaining for beta-EP. In intact animals, naltrexone treatment increased plasma and testicular androgen levels and this effect was confirmed in in-vitro incubations of minced testes. Naltrexone also induced a significant increase in germ cell degeneration. Our results indicated that an opioid system modulates the hypothalamus-pituitary-gonadal axis in the frog, Rana esculenta and, for the first time, we have shown that the testicular activity of a non-mammalian species may be regulated by opiates locally.


Assuntos
Testículo/metabolismo , beta-Endorfina/fisiologia , Animais , Encéfalo/metabolismo , Cromatografia Líquida de Alta Pressão , Técnicas de Cultura , Imuno-Histoquímica , Masculino , Naltrexona/farmacologia , Fragmentos de Peptídeos/fisiologia , Hipófise/metabolismo , Rana esculenta , Testículo/efeitos dos fármacos
11.
J Reprod Immunol ; 48(2): 81-98, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11011074

RESUMO

The aim of this study was to assess whether r-hTBP-1 (recombinant human tumor necrosis factor binding protein-1), the soluble form of tumor necrosis factor-alpha (TNF) receptor type 1 might be effective in counteracting the proliferation of ectopic endometrium using an in vivo experimental model of endometriosis. The in vivo model involved transplanting a square fragment of autologus uterine tissue onto the inner surface of the abdominal wall in rats. r-hTBP-1 was administered for 1 week at 10 mg/kg, s.c. divided into two daily injections. The gonadotropin-releasing hormone antagonist antide was used for reference and given at the dose of 2 mg/kg, s.c. every 3 days for 1 week. The animals were killed 2 and 9 days after the last treatment and the size of endometriotic implants measured. Blood samples and spleens were also taken for assessment of estradiol-17beta levels and natural killer (NK) activity in vitro against murine YAC cells, respectively. The results of this study indicate that r-hTBP-1 is effective in reducing the size of the endometriotic-like foci mainly at the later sacrifice time-point when they were significantly decreased by 64% as compared to control animals. As expected, antide induces an almost complete and statistically significant remission both at the 2-day (94%) and the 9-day (88%); sacrifice time-point. Histological examination indicates that, compared to controls, r-hTBP-1 induces a slightly increased degeneration of the stromal tissues of the implants at both examination times and, limitedly to the earlier observation time, of the mucosal epithelium. No differences in the spleen cell NK activity were observed at either sacrifice time-points in any treatment group. Estradiol-17beta concentrations are significantly decreased in the antide-treated groups only at 9 days while no statistically significant changes are found in the animals receiving r-hTBP-1. The results of this study carried out in a rat experimental model of endometriosis provide evidence of the potential effectiveness of r-hTBP-1 in this pathological condition and support the role of TNF in its development.


Assuntos
Antígenos CD/uso terapêutico , Endometriose/tratamento farmacológico , Receptores do Fator de Necrose Tumoral/uso terapêutico , Fator de Necrose Tumoral alfa/imunologia , Animais , Antígenos CD/imunologia , Células CHO , Cricetinae , Modelos Animais de Doenças , Endometriose/sangue , Endometriose/imunologia , Endometriose/patologia , Endométrio/imunologia , Endométrio/patologia , Estradiol/sangue , Feminino , Antagonistas de Hormônios/farmacologia , Humanos , Células Matadoras Naturais/imunologia , Oligopeptídeos/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores do Fator de Necrose Tumoral/imunologia , Receptores Tipo I de Fatores de Necrose Tumoral , Proteínas Recombinantes/uso terapêutico
12.
Ann N Y Acad Sci ; 883: 116-23, 1999 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-10586237

RESUMO

Normal peripheral nerve myelination depends on Schwann cell-basal lamina interactions. An important component of Schwann cell basal lamina is laminin--predominantly laminins 2 and 4. Mutations in the alpha 2 chain common to these two isoforms are associated with dysmyelination in mouse (dy) and man (congenital muscular dystrophy). Thus, laminin 2 and 4 receptors are also likely to be important for myelin formation. Several laminin 2/4 receptors are detected at the basal lamina surface of myelin-forming Schwann cells, namely, alpha 6 beta 4 and alpha 6 beta 1 integrins and dystroglycan. The evidence linking these receptors to myelination is suggestive, but not conclusive. Genetic studies have not yet confirmed a role for these molecules in myelin formation. Natural or targeted inactivation of alpha 6, beta 4, and beta 1 integrins and of dystroglycan have profound effects on other tissues causing embryonic or perinatal death before myelination. Therefore, to conditionally inactivate these receptors specifically in myelin-forming Schwann cells, we have constructed and initially characterized a P0-Cre transgene that activates Cre-mediated recombination of loxP-containing genes in peripheral nerve.


Assuntos
Integrases/metabolismo , Proteína P0 da Mielina/fisiologia , Receptores de Laminina/fisiologia , Células de Schwann/fisiologia , Proteínas Virais , Animais , Regulação da Expressão Gênica , Humanos , Integrases/genética , Laminina/fisiologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Proteína P0 da Mielina/genética , Especificidade de Órgãos , Receptores de Laminina/deficiência , Receptores de Laminina/genética , Proteínas Recombinantes/metabolismo , Nervo Isquiático/fisiologia , Nervo Isquiático/ultraestrutura , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
13.
Growth Horm IGF Res ; 14(3): 226-34, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15125884

RESUMO

The aim of this study was to assess the in vivo efficacy of monoPEGylated GRF(1-29)NH(2) having one PEG(5000) chains attached to either lysine 12 or 21 as compared to the GRF(1-29)NH(2) in rats and pigs. This analogue termed GRF-1PEG(5000) was tested after a single intravenous administration in rats and after a single intravenous or subcutaneous injection in pigs. After 1 h administration, GH concentrations returned to values close to controls in the group of rats injected with GRF(1-29)NH(2). In animals injected with the same dose of GRF-1PEG(5000), the AUC values corresponding to the whole period 0.5-48 h and particularly to the 0.5-8 h period were higher than in the placebo or in the GRF(1-29)NH(2) groups. Interestingly, two additional peaks were observed at about 6 and 8 h following administration. An increase in the response of the endogenous GH peaks was also observed in pigs administered GRF-1PEG(5000) by intravenous route. When GRF-1PEG(5000) was administered subcutaneously to pigs, a significant increase, as compared to placebo and GRF(1-29)NH(2,) in both GH and IGF-I levels was observed. This new analogue might find therapeutic application in paediatric growth hormone deficiency or in aging.


Assuntos
Hormônio Liberador de Hormônio do Crescimento/análogos & derivados , Polietilenoglicóis/química , Sermorelina/análogos & derivados , Sermorelina/farmacologia , Animais , Hormônio do Crescimento/sangue , Hormônio do Crescimento/metabolismo , Hormônio Liberador de Hormônio do Crescimento/sangue , Hormônio Liberador de Hormônio do Crescimento/metabolismo , Humanos , Injeções Intravenosas , Injeções Subcutâneas , Fator de Crescimento Insulin-Like I/análise , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Sermorelina/administração & dosagem , Suínos
14.
J Control Release ; 89(2): 297-310, 2003 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-12711452

RESUMO

Lipid microparticles (LMs) as a sustained release system for a gonadotropin release hormone (GnRH) antagonist (Antide) were prepared and evaluated. Antide loaded microparticles (Antide-LMs) were obtained by a cryogenic micronization process starting from two different monoglycerides (glyceryl monobehenate and glyceryl monostearate) and using two different incorporation methods (co-melting and solvent evaporation). Antide-LMs, 2% (w/w) loading, were characterized for drug incorporation by RP-HPLC, particle size by laser diffractometry and surface morphology by scanning electron microscopy. In vitro peptide release and in vitro biological activity were also studied. Serum Antide and testosterone levels, as pharmacodynamic marker, were assessed following subcutaneous administration in rats. Antide-LMs showed a mean diameter of approximately 30 micro m and variable Antide release depending on lipid matrix and incorporation method. In vivo experiments demonstrated that detectable Antide plasma levels were present, in the case of Antide-LMs based on Compritol E ATO obtained by co-melting procedure, for at least 30 days after dosing. Testosterone levels were consistent with prolonged pharmacokinetic profiles. In vitro release of Antide from LMs correlated well with the in vivo release. In conclusion, LMs can sustain the release of Antide for at least 1 month. The levels of the initial 'burst' and the extent of the pharmacodynamic effect can be influenced by the lipid characteristics and by process conditions.


Assuntos
Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Antagonistas de Hormônios/farmacocinética , Microesferas , Oligopeptídeos/farmacocinética , Animais , Preparações de Ação Retardada/farmacocinética , Feminino , Masculino , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley
15.
Life Sci ; 50(19): 1389-98, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1573972

RESUMO

In mammals, proopiomelanocortin-related peptides are involved in reproductive processes both at the hypothalamo-pituitary and ovarian levels. Using immunocytochemical, biochemical and physiological "in vitro" studies, we provide here evidence for a diffuse POMC-related opioid system in the frog Rana esculenta. Ovarian beta-endorphin (beta-EP) is expressed in thecal cells and changes during the reproductive cycle in an inverse relationship with follicular development. Seasonal changes in the ovary are different to those in the brain or in the pituitary. The ratio of acetylated vs native beta-EP in the ovary also changes over the reproductive period, affecting the biological activity of the peptide. During both the reproductive spring period and the summer post-reproductive phase pMol amounts of beta-EP stimulate follicular androgen secretion in vitro, in a naloxone-reversible way. In either period, an inhibition of estradiol, possibly mediated via other factors, is the result of opioid action. In conclusion, these data demonstrate for the first time the widespread presence of beta-EP-related peptides in the frog Rana esculenta. Both immunocytochemical and biochemical evidence, as well as in vitro responses, support a physiological role for beta-EP in ovarian seasonality during the reproductive cycle of this amphibian.


Assuntos
Ovário/metabolismo , Pró-Opiomelanocortina/fisiologia , Reprodução/fisiologia , beta-Endorfina/análise , Sequência de Aminoácidos , Análise de Variância , Androgênios/biossíntese , Animais , Cromatografia Líquida de Alta Pressão , Estradiol/biossíntese , Feminino , Imunofluorescência , Hipotálamo/química , Técnicas In Vitro , Dados de Sequência Molecular , Ovário/química , Hipófise/química , Radioimunoensaio , Rana esculenta , Estações do Ano , beta-Endorfina/biossíntese
16.
Panminerva Med ; 31(3): 148-50, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2601981

RESUMO

Cavernous hemangioma is a very rare disease if located in the ileum, but not an uncommon lesion if it occurs in the large bowel. The Authors report a case of small bowel cavernous hemangioma, and consider clinical, diagnostic and therapeutic aspects for an exact evaluation of the lesion.


Assuntos
Hemangioma Cavernoso/cirurgia , Neoplasias do Íleo/cirurgia , Adulto , Hemangioma Cavernoso/patologia , Humanos , Neoplasias do Íleo/patologia , Masculino
17.
Artigo em Inglês | MEDLINE | ID: mdl-8564791

RESUMO

In the frog, Rana esculenta, two molecular forms of GnRH, coeluting with chicken (c) GnRH-II and salmon (s) GnRH, have been detected using HPLC and radioimmunoassay. Mammalian (m) GnRH seems to be also present. In amphibians the role of cGnRH-II seems to be primarily the involvement in the regulation of neuroendocrine processes and, while the mGnRH has been postulated to act as a neurotransmitter and/or neuromodulator, the activity of sGnRH-like material has not been investigated. Therefore, we have treated the frogs with single or multiple injections of cGnRH-II or sGnRH (6 micrograms) or both peptides (6 micrograms of each) to detect differences in the response measured as testicular or plasma androgen (testosterone plus 5 alpha-dihydrotestosterone) concentration during the annual reproductive cycle. The basal profile of testicular and plasma androgen shows that the spring peak disappeared in control animals given multiple injections and kept in short-term captivity. We show in the treatment with cGnRH-II and/or sGnRH that the effects of the peptides depend on the season, the experimental design, and the tissue in which androgen levels were measured. In particular, both peptides strongly stimulate androgen production during the autumn-winter period, the time of the greater response to the GnRHs when basal levels of steroids are highest.


Assuntos
Di-Hidrotestosterona/sangue , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/farmacologia , Testículo/efeitos dos fármacos , Testosterona/sangue , Análise de Variância , Animais , Galinhas , Di-Hidrotestosterona/metabolismo , Masculino , Radioimunoensaio , Rana esculenta , Reprodução/efeitos dos fármacos , Salmão , Estações do Ano , Testículo/metabolismo , Testosterona/metabolismo
18.
Int Surg ; 72(1): 18-9, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3596971

RESUMO

Long term results are reported on 108 patients treated by curative mechanical anterior resection for midrectum carcinoma. The functional results were good but there was a large number of local recurrences for carcinoma at Dukes C stage (28% of the total cases). Oncological results suggest that greater importance should be given to early diagnosis and to pathogenesis and risk factors for recurrence.


Assuntos
Neoplasias Retais/cirurgia , Grampeadores Cirúrgicos , Humanos , Recidiva Local de Neoplasia
19.
Farmaco ; 46(3): 449-60, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1892502

RESUMO

The synthesis of some N,N-disubstituted 4-amino-5,6-dihydro-3-phenyl-2H-pyrano[3,2-d]-1-benzoxepin-2 -ones by reaction of phenylchloroketene with a series of N,N-disubstituted (E)-4-aminomethylene-3,4-dihydro-1-benzoxepin-5(2H)-ones, followed by dehydrochlorination of the primary adducts with DBN, is described. Some of these compounds showed a platelet antiaggregating activity in vitro slightly superior to that of acetylsalicylic acid, as well as weak local anesthetic and antiinflammatory activities in mice and rats, respectively.


Assuntos
Benzoxepinas/síntese química , Inibidores da Agregação Plaquetária/síntese química , Piranos/síntese química , Anestésicos Locais/síntese química , Animais , Antiarrítmicos/síntese química , Anti-Inflamatórios não Esteroides/síntese química , Benzoxepinas/farmacologia , Humanos , Técnicas In Vitro , Camundongos , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Piranos/farmacologia , Ratos
20.
Farmaco ; 45(12): 1309-25, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2090141

RESUMO

The synthesis of 1,3,3-trimethyl-6-phenyl-2-oxabicyclo[2.2.2]octan-6-ol 2 and 6-benzyl-1,3,3-trimethyl-2-oxabicyclo[2.2.2]octan-6-ol 3 starting from (+)-1,3,3-trimethyl-2-oxabicyclo[2.2.2]octan-6-one and phenylmagnesium bromide or benzylmagnesium chloride, respectively, is described. Alcohols 2 and 3 gave a series of omega-dialkylaminoalkyl ethers 4 by reaction as sodium salts with omega-chloroalkyldialkylamines in toluene solution. Some compounds 4, in particular those derived from alcohol 2, showed a strong platelet antiaggregating activity in vitro, superior to that of acetylsalicylic acid, as well as in general an appreciable local anesthetic activity and a weak sedative effect in mice.


Assuntos
Anestésicos Locais/síntese química , Compostos Bicíclicos com Pontes/síntese química , Inibidores da Agregação Plaquetária/síntese química , Anestesia , Anestésicos Locais/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Compostos Bicíclicos com Pontes/farmacologia , Clorofórmio , Humanos , Técnicas In Vitro , Espectroscopia de Ressonância Magnética , Camundongos , Atividade Motora/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Ratos , Espectrofotometria Infravermelho , Fibrilação Ventricular/induzido quimicamente , Fibrilação Ventricular/prevenção & controle
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