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1.
Pol J Vet Sci ; 26(4): 695-704, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38088429

RESUMO

The number of spermatozoa in the ejaculate is important for its quality and that of the sperm contained in it. The number of ejaculated spermatozoa is also associated with sperm dimensions. The aim of this study was to assess the morphological structure of sperm and the frequency of morphological abnormalities in sperm on the ejaculation performance of boars, measured as the total number sperm per ejaculate. The study was conducted using 648 ejaculates collected from 31 Large White boars and 30 Landrace boars. All ejaculates were analysed for basic physical characteristics and the frequency of sperm with morphological abnormalities. In addition, morphometric measurements of the sperm were made and used to calculate their shape indexes. As a result of our study it was noted that sperm from ejaculates with the most spermatozoa have shorter heads with a smaller area than sperm from ejaculates with a small or intermediate number of spermatozoa. Landrace boars produce semen of better quality, with a smaller percentage of sperm with major abnormalities, and the differences between the breeds increase with the number of spermatozoa in the ejaculate. The sperm from Landrace boars have larger heads and longer flagella than the sperm from Large White boars. The differences in sperm dimensions between breeds decrease as the total number of spermatozoa in the ejaculate increases. The number of spermatozoa in the ejaculate was shown to influence the dimensions of the sperm. The effect of the number of ejaculated sperm on ejaculate characteristics and sperm morphology depends on the breed of the male.


Assuntos
Líquidos Corporais , Sêmen , Suínos , Masculino , Animais , Contagem de Espermatozoides/veterinária , Espermatozoides , Ejaculação , Motilidade dos Espermatozoides
2.
Pol J Vet Sci ; 26(2): 311-314, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37389437

RESUMO

This is the first study to identify 23 protein spots corresponding to 13 proteins in mitochondria isolated from rabbit epididymal spermatozoa. In the group of protein spots identified in stress-induced samples, the abundance of 20 protein spots increased, whereas the abundance of three protein spots (GSTM3, CUNH9orf172, ODF1) decreased relative to the control. The results of this study provide valuable inputs for future research into the molecular mechanisms implicated in pathological processes during oxidative stress (OS).


Assuntos
Mitocôndrias , Proteínas Mitocondriais , Animais , Masculino , Coelhos , Proteínas Mitocondriais/genética , Estresse Oxidativo , Espermatozoides
3.
Phys Rev Lett ; 128(9): 091302, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35302802

RESUMO

We search for the signature of parity-violating physics in the cosmic microwave background, called cosmic birefringence, using the Planck data release 4. We initially find a birefringence angle of ß=0.30°±0.11° (68% C.L.) for nearly full-sky data. The values of ß decrease as we enlarge the Galactic mask, which can be interpreted as the effect of polarized foreground emission. Two independent ways to model this effect are used to mitigate the systematic impact on ß for different sky fractions. We choose not to assign cosmological significance to the measured value of ß until we improve our knowledge of the foreground polarization.

4.
Nat Med ; 27(10): 1789-1796, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34608333

RESUMO

Talimogene laherparepvec (T-VEC) is a herpes simplex virus type 1-based intralesional oncolytic immunotherapy approved for the treatment of unresectable melanoma. The present, ongoing study aimed to estimate the treatment effect of neoadjuvant T-VEC on recurrence-free survival (RFS) of patients with advanced resectable melanoma. An open-label, phase 2 trial (NCT02211131) was conducted in 150 patients with resectable stage IIIB-IVM1a melanoma who were randomized to receive T-VEC followed by surgery (arm 1, n = 76) or surgery alone (arm 2, n = 74). The primary endpoint was a 2-year RFS in the intention-to-treat population. Secondary and exploratory endpoints included overall survival (OS), pathological complete response (pCR), safety and biomarker analyses. The 2-year RFS was 29.5% in arm 1 and 16.5% in arm 2 (overall hazard ratio (HR) = 0.75, 80% confidence interval (CI) = 0.58-0.96). The 2-year OS was 88.9% for arm 1 and 77.4% for arm 2 (overall HR = 0.49, 80% CI = 0.30-0.79). The RFS and OS differences between arms persisted at 3 years. In arm 1, 17.1% achieved a pCR. Increased CD8+ density correlated with clinical outcomes in an exploratory analysis. Arm 1 adverse events were consistent with previous reports for T-VEC. The present study met its primary endpoint and estimated a 25% reduction in the risk of disease recurrence for neoadjuvant T-VEC plus surgery versus upfront surgery for patients with resectable stage IIIB-IVM1a melanoma.


Assuntos
Produtos Biológicos/administração & dosagem , Imunoterapia , Melanoma/terapia , Terapia Neoadjuvante , Adulto , Idoso , Produtos Biológicos/imunologia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/imunologia , Humanos , Masculino , Melanoma/genética , Melanoma/patologia , Melanoma/virologia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Recidiva Local de Neoplasia/virologia , Estadiamento de Neoplasias , Terapia Viral Oncolítica/tendências , Vírus Oncolíticos/genética , Vírus Oncolíticos/imunologia
5.
J Physiol Pharmacol ; 69(3)2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30342431

RESUMO

In this study, we tested the hypothesis that modulation of endogenous gonadotropin-releasing hormone (Gnrh) neuronal network activity alters the mRNA expression of nuclear receptor subfamily 5 group A member 1 (Nr5a1), through one of the component of Wnt pathway signaling - catenin beta 1 (Ctnnb1) (its co-activator), and its co-repressor nuclear receptor subfamily 0, group B member 1 (Nr0b1) in the female rat pituitary gland in vivo. Adult ovariectomized rats were given a serial infusion of Gnrh, kisspeptin-10, Gnrh + Gnrh antagonist (Antide), or kisspeptin-10 + kisspeptin antagonist (kisspeptin-234) into the third ventricle of the brain. The anterior pituitary and blood was used to mRNA and protein expression analysis. We demonstrated that Gnrh up-regulates Nr5a1 mRNA expression in the anterior pituitary and induces NR5A1 depletion in gonadotropes. Gnrh administration increased both Ctnnb1 mRNA expression and protein synthesis, and induced activation of cellular Ctnnb1 via translocation from the gonadotropes cytoplasm to nucleus. After kisspeptin-10 treatment, up-regulation of Nr0b1 mRNA and protein expression in the anterior pituitary was observed. These data indicate that Gnrh-neuron-mediated network activity alters Nr5a1 gene transcription and translation in gonadotrope cells and this effect may result from the changes induced in the Ctnnb1 and Nr0b1 gene/protein expression balance.


Assuntos
Receptor Nuclear Órfão DAX-1/metabolismo , Hormônio Liberador de Gonadotropina/farmacologia , Kisspeptinas/farmacologia , Adeno-Hipófise/efeitos dos fármacos , Fator Esteroidogênico 1/metabolismo , beta Catenina/metabolismo , Animais , Receptor Nuclear Órfão DAX-1/genética , Feminino , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Kisspeptinas/antagonistas & inibidores , Adeno-Hipófise/metabolismo , Ratos Wistar , Fator Esteroidogênico 1/genética , beta Catenina/genética
6.
Domest Anim Endocrinol ; 59: 75-80, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28013044

RESUMO

During lactation, the main surge of oxytocin is induced by a suckling stimulus. Previous studies have shown that salsolinol (1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline), a dopamine-derived compound, stimulates both the synthesis and the release of oxytocin in lactating sheep. The objective of the present study was to verify the hypothesis that salsolinol is involved in the mechanism that generates the oxytocin surge that occurs during suckling. Thus, a structural analogue of salsolinol, 1-methyl-3,4-dihydroisoquinoline (1MeDIQ), known to antagonize some of its actions, was infused into the third ventricle of the brain of lactating sheep nursing their offspring. Serial 30-min infusion of 1MeDIQ (4 × 60 µg/60 µL) or vehicle were administered at 30-min interval from 10 AM to 2 PM. The experimental period in every ewe consisted of a nonsuckling period (10 AM-12 PM) and a suckling period (12 PM-2 PM). Blood samples were collected every 10 min, to measure plasma oxytocin concentration by RIA. In control sheep, oxytocin surges of high amplitude were observed during the suckling period. The oxytocin surges induced by suckling were significantly (P < 0.01) diminished in sheep receiving 1MeDIQ infusions as compared to those that received control infusions. However, no significant effect of 1MeDIQ was observed on basal oxytocin release, before suckling. Furthermore, oxytocin release, as measured by the area under the hormone response curve (AUC), was significantly decreased by the administration of 1MeDIQ during the suckling period. This study shows that elimination of the effect of salsolinol within the central nervous system of lactating sheep attenuates the oxytocin surge induced by suckling. Therefore, salsolinol may be an important factor in the oxytocin-stimulating pathway in lactating mammals.


Assuntos
Isoquinolinas/farmacologia , Ocitocina/metabolismo , Ovinos/fisiologia , Animais , Área Sob a Curva , Estudos Cross-Over , Feminino , Isoquinolinas/administração & dosagem , Lactação , Ocitocina/sangue , Regulação para Cima
7.
J Physiol Pharmacol ; 67(3): 423-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27512003

RESUMO

The well-recognized sensitivity of the galanin gene in the anterior pituitary gland to estrogen suggests that estrogen receptor activity may influence the galaninergic system through modulation of galanin receptor (GALR) gene expression. Here, we evaluated the following: (i) the effects of estrogen on GALR mRNA expression; (ii) the estrogen receptor subtype that is specifically involved in this activity; and (iii) the effects of progesterone in the absence or presence of estrogen on galanin concentration in anterior pituitary gland. In the first experiment, ovariectomized 4-month-old rats were pre-treated subcutaneously with 17ß-estradiol (3 x 20 µg), the ESR1 (ERα) agonist propyl pyrazole triol (PPT) (3 x 5 mg), and the ESR2 (ERß) agonist diarylpropionitrile (DPN) (3 x 0.5 mg). In the second experiment, 4-month-old ovariectomized females received daily subcutaneous injections of 17ß-estradiol (3 x 20 µg), progesterone (2 x 5 mg), or combined estradiol (3 x 20 µg) and progesterone (2 x 5 mg). Anterior pituitaries were excised the day after the final 17ß-estradiol injection (experiment I) and 1 hour after receiving the second progesterone dose. Relative GALR1, GALR2, and GALR3 mRNA expression was evaluated using quantitative real-time PCR, and pituitary galanin concentration was determined using a specific radioimmunoassay. The results revealed that estrogen predominantly induced a 5-fold increase in GALR3 gene transcription. To a lesser extent, 17ß-estradiol also increased GALR1 mRNA expression, but had no effect on GALR2 mRNA levels. The estrogen-induced increase in GALR3 gene expression occurred exclusively through ESR1 activation. The increase in GALR1 gene expression occurred through activation of both estrogen receptor subtypes, but the ESR2 subtype was predominantly involved. Furthermore, the results revealed that progesterone regulates the activity of the pituitary galaninergic system by facilitating estradiol-induced galanin synthesis in the female rat anterior pituitary gland.


Assuntos
Estradiol/farmacologia , Galanina/genética , Hipófise/efeitos dos fármacos , Progesterona/farmacologia , Precursores de Proteínas/genética , Receptores de Galanina/genética , Animais , Receptor alfa de Estrogênio/agonistas , Receptor beta de Estrogênio/agonistas , Feminino , Nitrilas/farmacologia , Ovariectomia , Fenóis/farmacologia , Hipófise/metabolismo , Propionatos/farmacologia , Pirazóis/farmacologia , Ratos Wistar
8.
J Neuroendocrinol ; 28(3): 12362, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26749292

RESUMO

Salsolinol (1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline) is a dopamine-derived compound present in the central nervous system and pituitary gland. Several previous studies on lactating sheep and rats have reported that salsolinol plays a crucial role in the regulation of prolactin secretion. The present study investigated the effects of salsolinol, which was infused into the third ventricle of the brain, on oxytocin expression and release in lactating sheep, 48 h after weaning of 8-week-old lambs. Serial 30-min infusions of salsolinol and vehicle were performed at 30-min intervals from 10.00 to 15.00 h. Blood samples were collected every 10 min. The supraoptic nucleus (SON), paraventricular nucleus (PVN) and posterior pituitary were collected immediately after the experiment. Expression levels of mRNAs for oxytocin and peptidylglycine α-amidating monooxygenase (PAM), the terminal enzyme in the oxytocin synthesis pathway, were measured using a real-time polymerase chain reaction. Oxytocin peptide content in the posterior pituitary was measured by an enzyme-linked immunosorbent assay, and plasma oxytocin concentration was measured by radioimmunoassay. Salsolinol treatment significantly up-regulated oxytocin and PAM gene expression in the SON (P < 0.01 and P < 0.05, respectively), PVN (P < 0.01 and P < 0.05, respectively) and posterior pituitary (P < 0.05 and P < 0.05, respectively). Oxytocin peptide content in the posterior pituitary and the area under the response curve of plasma oxytocin were significantly (P < 0.05 and P < 0.01, respectively) higher in salsolinol-treated sheep than in control animals. The present study shows for the first time that salsolinol stimulates oxytocin secretion during lactation in sheep.


Assuntos
Isoquinolinas/farmacologia , Lactação/efeitos dos fármacos , Ocitocina/genética , Ocitocina/metabolismo , Ovinos , Animais , Feminino , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Infusões Intraventriculares , Isoquinolinas/administração & dosagem , Lactação/genética , Lactação/metabolismo , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismo , Ocitocina/sangue , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Gravidez , Ovinos/genética , Ovinos/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
9.
J Fish Biol ; 87(4): 1059-71, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26377071

RESUMO

In this study, habitat use by Mugil cephalus was investigated in the waters of the west coast of the North Island of New Zealand by analysing microchemical composition of otoliths (laser-ablation inductively coupled plasma mass spectrometry) obtained from individuals from commercial fish stocks and research surveys. Results of this study show that M. cephalus at the southern limits of its distribution display highly flexible migratory behaviour with extensive use of freshwater and brackish habitats, potentially enabling them to maximize foraging opportunities. Mugil cephalus can tolerate a wide range of salinities and can therefore utilize higher productivity areas, such as estuaries and eutrophic riverine lakes. Finally, M. cephalus populations across a range of climates and latitudes appear to differ in the extent to which they utilize freshwater and brackish habitats, possibly with increasing penetration of fresh waters with increasing latitude.


Assuntos
Comportamento Animal , Água Doce , Água do Mar , Smegmamorpha/fisiologia , Animais , Clima , Comportamento de Retorno ao Território Vital , Nova Zelândia , Membrana dos Otólitos/química , Densidade Demográfica , Dinâmica Populacional , Salinidade
10.
Anim Reprod Sci ; 141(1-2): 62-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23953813

RESUMO

To learn the involvement of endogenous opioid peptides (EOP) in the regulation of reproductive activity in ruminants, the effects of different opioid antagonists on luteinizing hormone (LH) secretion were determined in sheep during the early stage of lactation. The opioid receptor antagonists: naloxone (all types of receptors, n=5), naloxonazine (µ receptor, n=5), GNTI- (κ receptor, n=5), naltrindole (δ receptor, n=5) or the vehicle (control, n=5) were infused intracerebroventricularly in a series of five 30-min infusions (60µg/60µl) at 30-min intervals. The period of the experiment included the non-suckling (10:00-12.30) and suckling (12.30-15.00) periods. Blood samples were collected from 10.00 to 15.00 at 10-min intervals, and plasma LH concentration was assayed by the radioimmunoassay method. The obtained results showed that blocking of the EOP action within the central nervous system in lactating sheep caused a significant (p<0.001) increase in LH concentration in all treated groups, in comparison to the control. In the naloxone-treated group, a significant (p<0.05) increase in LH secretion also occurred during suckling. The amplitude of LH pulses increased significantly in the naloxonazine- (p<0.01) and naltrindole- (p<0.05) treated ewes compared to the control; there were no significant differences in the frequency of LH pulses among the groups. In conclusion, our study indicates that EOP play a crucial role in the mechanism inhibiting GnRH/LH axis activity in lactating sheep and that the ligands for µ opioid receptor may have the highest inhibitory effect.


Assuntos
Regulação da Expressão Gênica/fisiologia , Lactação/fisiologia , Hormônio Luteinizante/metabolismo , Receptores Opioides/metabolismo , Ovinos/fisiologia , Animais , Feminino , Guanidinas/farmacologia , Hormônio Luteinizante/sangue , Hormônio Luteinizante/genética , Morfinanos/farmacologia , Naloxona/análogos & derivados , Naloxona/farmacologia , Naltrexona/análogos & derivados , Naltrexona/farmacologia , Antagonistas de Entorpecentes/farmacologia
12.
Reprod Domest Anim ; 47(5): 746-51, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22212243

RESUMO

Suckling by newborns induces a surge of lactogenic hormones, that is prolactin and growth hormone (GH), in mother's body, with endogenous opioid peptide (EOP) participating in generation of this surge. The aim of the current study was to investigate which types of opioid receptors are involved in generation of the GH surge in ewes during suckling. A series of intracerebroventricular infusions of opioid receptors antagonists: naloxone (for all types of receptors), naloxonazine (specific for µ receptor) and 5'-guanidinonaltrindole (GNTI--specific for κ receptor) and the vehicle (control) were performed in nursing sheep during the fifth week of lactation. All infusions were carried out in a serial manner: five 30-min infusions (60 µg/60 µl) from 10:00 to 15:00, at 30-min intervals. The period of the experiment consisted of the non-suckling (10:00-12:30) and suckling (12:30-15:00) periods. Simultaneously, blood samples were collected at 10-min intervals to determine plasma GH concentration by radioimmunoassay. Suckling evoked a rapid increase in GH concentration in control ewes. Naloxone and naloxonazine significantly decreased both the basal GH release in the non-suckling period and the suckling-induced GH surge. Specifically, the suppressive effect concerned either the duration or the amplitude of the GH surge. In contrast, GNTI did not significantly affect the GH release. In conclusion, the EOPs may affect the regulatory process of GH secretion in lactating sheep, especially through µ opioid receptor.


Assuntos
Hormônio do Crescimento/metabolismo , Lactação/fisiologia , Receptores Opioides mu/fisiologia , Ovinos/fisiologia , Animais , Feminino , Hormônio do Crescimento/sangue , Guanidinas/administração & dosagem , Infusões Intraventriculares , Morfinanos/administração & dosagem , Naloxona/administração & dosagem , Naloxona/análogos & derivados , Receptores Opioides kappa/antagonistas & inibidores , Receptores Opioides mu/antagonistas & inibidores
13.
Cancer Chemother Pharmacol ; 68(3): 733-41, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21161528

RESUMO

PURPOSE: Conatumumab is a fully human monoclonal agonist antibody against human death receptor 5 (DR5). The primary objectives of this phase 1 study were to assess the safety, tolerability, and pharmacokinetics (PK) of conatumumab in Japanese patients with advanced solid tumors. METHODS: This is an open-label ascending dose study with a starting dose level of 3 mg/kg. Subsequent doses of 10 and 20 mg/kg were planned. Six patients were enrolled into 1 of 3 dose cohorts (3, 10, or 20 mg/kg) of conatumumab administered intravenously once every 2 weeks as a single agent. No conatumumab was administered on day 43 to allow the assessment of terminal PK parameters. The primary endpoints were the incidence of dose-limiting toxicities (DLTs) and assessment of PK parameters of conatumumab. RESULTS: Eighteen patients received at least 1 dose of conatumumab. There were no DLTs observed as defined in the protocol. No patients had an adverse event leading to conatumumab discontinuation. Conatumumab demonstrated dose-linear kinetics. A best response of stable disease was reported in nine patients. Monocytes were found to express DR5 and showed a high degree of conatumumab receptor occupancy after treatment at all dose levels. CONCLUSIONS: Conatumumab administered up to 20 mg/kg once every 2 weeks was well tolerated in Japanese patients with advanced solid tumors. Adverse events and PK in these patients were similar to those in the first in human (FIH) study.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/agonistas , Adulto , Idoso , Anticorpos/análise , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Área Sob a Curva , Estudos de Coortes , Relação Dose-Resposta a Droga , Determinação de Ponto Final , Feminino , Meia-Vida , Humanos , Injeções Intravenosas , Japão , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Neoplasias/patologia
15.
Neuroscience ; 170(4): 1165-71, 2010 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-20708656

RESUMO

Endogenous opioid peptides (EOP) and dopamine (DA)-derived salsolinol are implicated in the suckling-induced prolactin surge. The aim of this study was to investigate the relationship between the opioidergic and salsolinergic activity in the mediobasal hypothalamus of nursing sheep. The sheep were infused intracerebroventricularly with opioid receptors antagonists: naloxone (all types of receptors, n=6); naloxonazine (µ receptor, n=6) or the vehicle (control, n=6) in a series of five 30-min infusions (60 µg/60 µl) from 10:00 to 15:00, at 30-min intervals. The period of the experiment included the non-suckling (10:00-12:30) and suckling (12:30-15:00) periods. Simultaneously, a push-pull perfusion of the infundibular nucleus/median eminence was performed in every sheep to study the dopaminergic system activity. Blood samples were also collected at 10-minute intervals to determine plasma prolactin concentration. Both the mean perfusate salsolinol and plasma prolactin concentrations were higher during the suckling vs. non-suckling (P<0.001) period in the control. The perfusate DA concentration was below the detection limit in this group. Treatment with either naloxone or naloxonazine significantly (P<0.01) diminished plasma prolactin concentration, as compared with the controls and blocked the prolactin surge during suckling. In drug-infused sheep, the perfusate salsolinol concentration was below the detection limit but the increased DA and its metabolite 3,4-dihydroxyphenylacetic acid concentrations were observed. In conclusion, the stimulatory action of EOP on prolactin secretion in nursing females is mediated, at least in part, by salsolinol, and the ligands for µ opioid receptor may be the primary factors of this relationship, especially with respect to the suckling-induced prolactin surge.


Assuntos
Isoquinolinas/metabolismo , Lactação , Antagonistas de Entorpecentes , Prolactina/metabolismo , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Animais Lactentes , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Dopamina/metabolismo , Feminino , Naloxona/análogos & derivados , Naloxona/farmacologia , Prolactina/sangue , Receptores Opioides mu/antagonistas & inibidores , Ovinos
16.
Reprod Domest Anim ; 45(5): e54-60, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19747187

RESUMO

Salsolinol, a dopamine-related compound and prolactin-producing cells were found in the ovine hypothalamus. This study was designed to test the hypothesis that salsolinol, acting from the CNS level, is able to stimulate pituitary prolactin release as well as prolactin mRNA expression in the anterior pituitary cells (AP) and in the mediobasal hypothalamus (MBH) in lactating ewes. The intracerebroventricular infusions of salsolinol in two doses, total of 50 ng or 5 µg, were performed in a series of five 10-min infusions at 20-min intervals. All infusions were made from 12:30 to 15:00 and the pre-infusion period was from 10:00 to 12.30 h. The prolactin concentration in plasma samples, collected every 10 min, was determined by radioimmunoassay; prolactin mRNA expression in AP and MBH tissues was determined by real-time PCR. The obtained results showed that salsolinol infused at the higher dose significantly (p < 0.001) increased plasma prolactin concentration in lactating ewes, when compared with the concentration noted before the infusion and with that in lactating controls. In lactating ewes, the relative levels of prolactin mRNA expression in the AP and MBH were up to twofold and fivefold higher respectively than in non-lactating ewes (p < 0.05). In our experimental design, salsolinol did not significantly affect the ongoing process of prolactin gene expression in these tissues. We conclude that in ewes, salsolinol may be involved, at least, in the process of stimulation of prolactin release during lactation and that hypothalamic prolactin plays an important role in the central mechanisms of adaptation to lactation.


Assuntos
Hipotálamo/metabolismo , Isoquinolinas/metabolismo , Lactação/fisiologia , Prolactina/metabolismo , Ovinos/fisiologia , Animais , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Infusões Intraventriculares , Isoquinolinas/administração & dosagem , Prolactina/sangue , Prolactina/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Distribuição Aleatória
17.
Phys Rev Lett ; 102(13): 131301, 2009 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-19392345

RESUMO

We present a model-independent method to test for scale-dependent non-Gaussianities in combination with scaling indices as test statistics. Therefore, surrogate data sets are generated, in which the power spectrum of the original data is preserved, while the higher order correlations are partly randomized by applying a scale-dependent shuffling procedure to the Fourier phases. We apply this method to the Wilkinson Microwave Anisotropy Probe data of the cosmic microwave background and find signatures for non-Gaussianities on large scales. Further tests are required to elucidate the origin of the detected anomalies.

18.
J Immunol ; 167(1): 147-55, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11418643

RESUMO

There is accumulating evidence that CD4(+) T cell responses are important in antitumor immunity. Accordingly, we generated CD4(+) T cells against the murine CT26 colon cancer. Three of three independent CT26-specific CD4(+) hybridomas were found to recognize the high m.w. precursor of the env gene product gp90. The CD4(+) response was completely tumor specific in that the same glycoprotein expressed by other tumors was not recognized by the CT26-specific hybridomas. The recognition of gp90 by the hybridomas was strictly dependent on the conformation of gp90. Different procedures that disrupted the conformation of the glycoprotein, such as disulfide bond reduction and thermal denaturation, completely abrogated recognition of gp90 by all three hybridomas. In CT26 cells, but not in other tumor cells tested, a large proportion of gp90 was retained in the endoplasmic reticulum, mostly bound to the endoplasmic reticulum chaperone, calreticulin. Although calreticulin was not essential for the stimulation of the gp90-specific hybridomas, most of the antigenic form of gp90 was bound to it. The antigenicity of gp90 correlated well with calreticulin binding, reflecting the fact that specificity of binding of calreticulin to its substrate required posttranslational modifications that were also necessary for the generation of this tumor-specific CD4(+) epitope.


Assuntos
Antígenos de Neoplasias/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Retículo Endoplasmático/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Epitopos Imunodominantes/metabolismo , Ribonucleoproteínas/metabolismo , Animais , Antígenos de Neoplasias/química , Linfócitos T CD4-Positivos/imunologia , Calreticulina , Retículo Endoplasmático/imunologia , Epitopos de Linfócito T/imunologia , Feminino , Produtos do Gene env/metabolismo , Temperatura Alta , Hibridomas/metabolismo , Vírus da Leucemia Murina/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Camundongos Transgênicos , Ligação Proteica/imunologia , Conformação Proteica , Desnaturação Proteica , Células Tumorais Cultivadas
19.
J Exp Med ; 193(7): 839-46, 2001 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-11283156

RESUMO

Dendritic cells (DCs), unique antigen-presenting cells (APCs) with potent T cell stimulatory capacity, direct the activation and differentiation of T cells by providing costimulatory signals. As such, they are critical regulators of both natural and vaccine-induced immune responses. A new B7 family member, B7-DC, whose expression is highly restricted to DCs, was identified among a library of genes differentially expressed between DCs and activated macrophages. B7-DC fails to bind the B7.1/2 receptors CD28 and cytotoxic T lymphocyte-associated antigen (CTLA)-4, but does bind PD-1, a receptor for B7-H1/PD-L1. B7-DC costimulates T cell proliferation more efficiently than B7.1 and induces a distinct pattern of lymphokine secretion. In particular, B7-DC strongly costimulates interferon gamma but not interleukin (IL)-4 or IL-10 production from isolated naive T cells. These properties of B7-DC may account for some of the unique activity of DCs, such as their ability to initiate potent T helper cell type 1 responses.


Assuntos
Apresentação de Antígeno , Antígenos de Superfície , Antígeno B7-1/imunologia , Células Dendríticas/imunologia , Linfócitos T/imunologia , Sequência de Aminoácidos , Animais , Antígenos CD , Proteínas Reguladoras de Apoptose , Antígenos CD28/metabolismo , Biblioteca Gênica , Humanos , Interferon gama/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Proteína 2 Ligante de Morte Celular Programada 1 , Receptor de Morte Celular Programada 1 , Ligação Proteica , Proteínas/metabolismo , Homologia de Sequência de Aminoácidos
20.
J Biol Chem ; 273(34): 21846-55, 1998 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-9705323

RESUMO

The major structural proteins present in the paraflagellar rod of Trypanosoma cruzi migrate on SDS-polyacrylamide gels as two distinct electrophoretic bands. The gene encoding a protein present in the faster migrating band, designated PAR 2, has been identified previously. Here we report the isolation and partial characterization of three genes, designated par 1, par 3, and par 4, that encode proteins present in the two paraflagellar rod protein bands. Peptide-specific polyclonal antibodies and monoclonal antibodies against the four proteins encoded by these genes shows that PAR 1 and PAR 3 are present only in the slower migrating paraflagellar rod band, and that PAR 2 and PAR 4 are present only in the faster migrating band. Analysis of the nucleotide sequence of these genes and the amino acid sequence of the conceptual proteins encoded by them indicates that par 2 shares high sequence similarity with par 3 and both are members of a common gene family, of which par 1 may be a distant member. Analysis of gene copy number and steady-state RNA levels suggest that the close stoichiometric ratio of the four PAR proteins is likely maintained by homeostatic regulation of RNA levels rather than gene dosage.


Assuntos
Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Trypanosoma cruzi/química , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Western Blotting , Dados de Sequência Molecular , Mapeamento de Peptídeos , Conformação Proteica , Proteínas de Protozoários/imunologia , Proteínas Recombinantes/química
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