RESUMO
The magnitude of ovulation rate (OR) after hormonal induction in sheep should be considered when prolific genotypes are used. We investigated for the first time the effect of the Vacaria allele and its combined effect with the Booroola prolificacy mutation on OR after hormonal treatment during breeding and anoestrous season. A hundred forty-nine Ile de France crossbred ewes, raised in natural pastures in South Brazil, were used to evaluate the OR after treatment with progestagen (MAP) followed or not by equine chorionic gonadotrophin (eCG) treatment (MAP + eCG). During the breeding season, 96% MAP-treated ewes ovulated in comparison to 97% of MAP + eCG-treated females. The double heterozygous carriers (BNVN) presented the higher OR, followed by the single Vacaria (NNVN) and Booroola (BNNN) heterozygous females and least the wild-type (NNNN) ewes. During anoestrus, 96% eCG-treated ewes ovulated, in contrast to 6% treated with MAP alone. The OR of the gonadotrophin-treated females was higher in BNVN and BNNN than NNVN and NNNN ewes. An additive effect in the OR of the two mutations was observed since OR in double heterozygous ewes was similar to the sum of the effects of the alleles of the single heterozygous carrier ewes.
Assuntos
Alelos , Gonadotropinas Equinas/farmacologia , Indução da Ovulação/veterinária , Ovulação/genética , Progestinas/farmacologia , Ovinos/genética , Animais , Feminino , Gonadotropinas Equinas/administração & dosagem , Heterozigoto , Mutação , Ovulação/efeitos dos fármacos , Progestinas/administração & dosagemRESUMO
Litter size (LS) in sheep is determined mainly by ovulation rate (OR). Several polymorphisms have been identified in the growth differentiation factor 9 (GDF9) gene that result in an increase in OR and prolificacy of sheep. Screening the databank of the Brazilian Sheep Breeders Association for triplet delivery, we identified flocks of prolific Ile de France ewes. After resequencing of GDF9, a point mutation (c.943C>T) was identified, resulting in a non-conservative amino acid change (p.Arg315Cys) in the cleavage site of the propeptide. This new allele was called Vacaria (FecG(v) ). A flock of half-sib ewes was evaluated for OR in the first three breeding seasons, and Vacaria heterozygotes had higher OR (P < 0.001), averaging 2.1 ± 0.1 when compared to 1.2 ± 0.1 in wild-type ewes. The OR was also influenced by age, increasing in the second and third breeding seasons (P < 0.001). In flocks segregating this allele, the LS was higher in mutant sheep (P < 0.001), averaging 1.61 ± 0.07 in heterozygotes and 1.29 ± 0.03 in wild-type ewes. Analysis of homozygote reproductive tract morphology revealed uterine and ovarian hypoplasia. Ovarian follicles continue to develop up to small antral stages, although with abnormal oocyte morphology and altered arrangement of granulosa cells. After the collapse of the oocyte in most follicles, the remaining cells formed clusters that persisted in the ovary. This SNP is useful to improve selection for dam prolificacy and also as a model to investigate GDF9 post-translation processing and the fate of the follicular cells that remain after the oocyte demise.
Assuntos
Fator 9 de Diferenciação de Crescimento/genética , Infertilidade/genética , Tamanho da Ninhada de Vivíparos/genética , Ovulação/genética , Polimorfismo de Nucleotídeo Único , Ovinos/genética , Animais , Proteína Morfogenética Óssea 15/genética , Cruzamento , Feminino , Genótipo , Heterozigoto , Homozigoto , Folículo Ovariano/anormalidades , Folículo Ovariano/crescimento & desenvolvimento , Análise de Sequência de DNA , Ovinos/crescimento & desenvolvimentoRESUMO
Brazilian Santa Inês (SI) sheep are very well-adapted to the tropical conditions of Brazil and are an important source of animal protein. A high rate of twin births was reported in some SI flocks. Growth and Differentiation Factor 9 (GDF9) and Bone Morphogenetic Protein 15 (BMP15) are the first two genes expressed by the oocyte to be associated with an increased ovulation rate in sheep. All GDF9 and BMP15 variants characterized, until now, present the same phenotype: the heterozygote ewes have an increased ovulation rate and the mutated homozygotes are sterile. In this study, we have found a new allele of GDF9, named FecG(E) (Embrapa), which leads to a substitution of a phenylalanine with a cysteine in a conservative position of the mature peptide. Homozygote ewes presenting the FecG(E) allele have shown an increase in their ovulation rate (82%) and prolificacy (58%). This new phenotype can be very useful in better understanding the genetic control of follicular development; the mechanisms involved in the control of ovulation rate in mammals; and for the improvement of sheep production.
Assuntos
Fator 9 de Diferenciação de Crescimento/genética , Ovulação , Ovinos/genética , Animais , Proteína Morfogenética Óssea 15/genética , Feminino , Prole de Múltiplos Nascimentos/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Ovinos/fisiologiaRESUMO
The prolificacy variation in sheep makes it an excellent animal model to understand the mechanisms regulating ovulation rate. Identification of mutations responsible for the increased prolificacy of the Inverdale, Booroola, Javanese, Cambridge and Belclare sheep open new avenues of investigation for the paracrine control of folliculogenesis. To date, all known mutations are in genes from ligands or receptors of the transforming growth factor beta superfamily, and point to the bone morphogenetic protein family of peptides as local regulators of ovarian follicle growth. The mechanism of action of the mutated genes is not fully understood, but results in the ovulation of a higher number of follicles with smaller diameter and fewer granulosa cells than that of the wildtype, thus speeding the differentiation of ovulatory follicles. Comparisons of the performance of Booroola-crossed flocks in different countries showed that carriers of the prolificacy mutation have higher ewe productivity but also higher perinatal mortality and lighter weight lambs. Their economic impact on the sheep industry depends on farm environment and management. Nevertheless, the diagnostic tests now available to identify the genetic mutations resulting in increased ovulation rate, will simplify the introduction of these mutations and their monitoring in flocks for research and commercial purposes.
Assuntos
Cruzamento/economia , Ovulação/genética , Carneiro Doméstico/crescimento & desenvolvimento , Carneiro Doméstico/genética , Animais , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/fisiologia , Feminino , Mutação , Folículo Ovariano/crescimento & desenvolvimentoRESUMO
The Booroola (FecB) phenotype is associated with a mutation in the bone morphogenetic protein (BMP) receptor 1B. The BMP action is important during development; surprisingly the only differences so far observed in adult animals are restricted to the ovaries where precocious development of the antral follicles and increased ovulation rate of mutant ewes is observed. The internal organs of 17 ewes homozygous for the mutation (BB) and 18 wild-type ewes (++) were macroscopically examined and weighed. No macroscopic differences were found, and the weight of the heart, liver, lungs, kidneys, and spleen were similar for both genotypes (P > 0.05). In contrast, the adrenals of BB ewes were lighter than those of ++ ewes (P < 0.05). The effect of the mutation on the adrenal function of cortisol secretion was measured at basal level and after an adrenocorticotrophic hormone challenge, before and after dexamethasone suppression. The Booroola mutation had no effect (P > 0.05) in any of these conditions. These findings indicate that the Booroola mutation also affects the size of the adrenal glands and suggest that the mutated gene could be important in the development of other organs in addition to the ovary. However, in the mutant ewes the function of the adrenal glands is not compromised or it is compensated.
Assuntos
Glândulas Suprarrenais/patologia , Mutação , Proteínas Serina-Treonina Quinases/genética , Receptores de Fatores de Crescimento/genética , Hormônio Adrenocorticotrópico/farmacologia , Animais , Receptores de Proteínas Morfogenéticas Ósseas Tipo I , Dexametasona/farmacologia , Feminino , Genótipo , Glucocorticoides/farmacologia , Homozigoto , Hidrocortisona/sangue , Concentração Osmolar , Fenótipo , OvinosRESUMO
Cytokines released by immune system cells play an important role in cyst enlargement. This study aimed to determine, by ELISA, the levels of granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin 3 (IL-3), and IL-6 in fluid and tissue from human radicular cysts. GM-CSF was found in 42.8% of the fluid samples (164.3 pg/mL) and IL-6 in 92.8% (641.4 pg/mL). No IL-3 was detected in any fluid samples. In the tissue samples, 28.6% were positive for IL-3 (369.2 pg/mL), 86.4% for IL-6 (92.4 pg/mL), and 95.8% for GM-CSF (200.5 pg/mL). It can be concluded that GM-CSF and IL-6 were widely found in the fluid and tissue samples. In contrast, IL-3 was found only in the cystic tissue, even though in few lesions. These cytokines may contribute to the inflammation, cystic growth, and bone resorption that characterize cystic lesions.
Assuntos
Líquido Cístico/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/análise , Interleucina-3/análise , Interleucina-6/análise , Cisto Radicular/imunologia , Perda do Osso Alveolar/imunologia , Líquido Cístico/química , Ensaio de Imunoadsorção Enzimática , Humanos , Cisto Radicular/química , Estatísticas não ParamétricasRESUMO
To investigate the role of 5-HT in human anxiety, the 5-HT releaser and uptake blocker d-fenfluramine (FEN) was administered to healthy volunteers under two models of experimental anxiety. The first was a simulated public speaking (SPS) test consisting of talking in front of a video camera, anxiety being evaluated mainly by self-rating scales. The second was a conditioned fear test, in which the changes in skin electrical conductance caused by a tone associated once with an aversive white noise were measured. The doses of 15 and 30 mg FEN, PO, decreased anxiety induced by SPS in a dose-dependent way, as indicated by the anxiety factor of Norris Visual Analogue Mood Scale. In the conditioned fear test, however, the amplitude and level of skin conductance responses to the conditioned aversive stimulus were not significantly changed by FEN. The differential effects of FEN in these human experimental models of anxiety, together with similar results reported in rats, support the view that 5-HT exerts a dual action on brain mechanisms regulating anxiety, facilitating conditioned while inhibiting unconditioned fear. The presumed reduction in unconditioned fear caused by FEN may have implications for the treatment of panic disorder.
Assuntos
Ansiedade/tratamento farmacológico , Fenfluramina/uso terapêutico , Serotoninérgicos/uso terapêutico , Adolescente , Adulto , Ansiedade/etiologia , Método Duplo-Cego , Feminino , Resposta Galvânica da Pele , Hemodinâmica , Humanos , MasculinoRESUMO
The main objective of this transverse study was to investigate the presence of serologic markers of infection with the hepatitis B virus (HBsAg or HBsAb) among dentistry students before and after they began to have contact with patients; among dentists; and, for purposes of comparison with the latter group, among professionals outside the biological sciences in the municipality of Belo Horizonte, Brazil. Secondarily, the association between the prevalence of infection, the frequency of performing potentially infective dental procedures, and the use of protective barriers was studied. Among 88 students at the beginning of their course of study (average age = 20.0 years), the proportion of positive individuals was 6.8%; among 84 students concluding their studies (average age = 23.4 years), the proportion was 7.1% (P = 0.829). In the group of 202 dentists (average age = 44.0 years), 23.3% were positive, while among the other professionals (202 individuals, average age = 44.3 years), the proportion was 14.9%, for an odds ratio of 1.75 (95% CI = 1.02 to 2.98; P = 0.042). While 91.7% of the students reported that they routinely used surgical masks, only 16.7% said they regularly wore gloves. Among the dentists, these proportions were 49.8% and 9.4%, respectively. No association was found between risk factors and the use of such protection and the prevalence of infection in the different groups studied.
Assuntos
Odontólogos , Anticorpos Anti-Hepatite B/análise , Antígenos de Superfície da Hepatite B/análise , Hepatite B/epidemiologia , Estudantes de Odontologia , Adulto , Brasil/epidemiologia , Estudos Transversais , Feminino , Luvas Protetoras , Hepatite B/prevenção & controle , Hepatite B/transmissão , Humanos , Masculino , Máscaras , Pessoa de Meia-Idade , OcupaçõesRESUMO
To further explore the role of serotonin (5-HT) in anxiety, 28 healthy volunteers received in a double-blind study d-fenfluramine (30 mg, p.o.) or placebo, and were submitted to a simulated public speaking test (SPS), consisting of speaking in front of a video camera. The SPS induced significant increases in subjective anxiety evaluated by the visual analogue mood scale of Norris [MANCOVA, F(1.66,39.93) = 8.51, P < 0.001], as well as in systolic blood pressure [F(3,72) = 5.70, P = 0.001] and in heart rate [F(3,72) = 3.95, P = 0.012]. The drug decreased the anxiety factor [F(1,23) = 5.21, P = 0.032], without significantly affecting physical sedation, mental sedation or other feelings and attitudes. Also, the physiological measurements were not significantly changed by d-fenfluramine. Reported evidence shows that d-fenfluramine releases 5-HT from nerve endings and blocks 5-HT reuptake, indirectly stimulating postsynaptic 5-HT receptors. Therefore, the present results indicate that 5-HT inhibits the neural substrate of SPS-induced anxiety.
Assuntos
Ansiedade/prevenção & controle , Fenfluramina/farmacologia , Comportamento Verbal/efeitos dos fármacos , Adolescente , Adulto , Recursos Audiovisuais , Pressão Sanguínea/efeitos dos fármacos , Método Duplo-Cego , Feminino , Humanos , Masculino , Receptores de Serotonina/efeitos dos fármacos , Escala de Ansiedade Frente a TesteRESUMO
To further explore the role of serotonin (5-HT) in anxiety, 28 healthy volunteers received in a double-blind study d-fenfluramine (30 mg, p.o.) or placebo, and were submitted to a simulated public speaking test (SPS), consisting of speaking in front of a video camera. The SPS induced significant increases in subjective anxiety evaluated by the visual analogue mood scale of Norris [MANCOVA, F(1.66,39.93) = 8.51, P < 0.001], as well as in systolic blood pressure [F(3,72) = 5.70, P = 0.001] and in heart rate [F(3,72) = 3.95, P = 0.012]. The drug decreased the anxiety factor [F(1,23) = 5.21, P = 0.032], without significantly affecting physical sedation, mental sedation or other feelings and attitudes. Also, the physiological measurements were not significantly changed by d-fenfluramine. Reported evidence shows that d-fenfluramine releases 5-HT from nerve endings and blocks 5-HT reuptake, indirectly stimulating postsynaptic 5-HT receptors. Therefore, the present results indicate that 5-HT inhibits the neural substrate of SPS-induced anxiety
Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Ansiedade/prevenção & controle , Fenfluramina/farmacologia , Comportamento Verbal/efeitos dos fármacos , Pressão Arterial , Recursos Audiovisuais , Método Duplo-Cego , Receptores de Serotonina/efeitos dos fármacos , Escala de Ansiedade Frente a TesteRESUMO
Results of a HIV prevalence study conducted in hemophiliacs from Belo Horizonte, Brazil are presented. History of exposure to acellular blood components was determined for the five year period prior to entry in the study, which occurred during 1986 and 1987. Patients with coagulations disorders (hemophilia A = 132, hemophilia B = 16 and coagulation disorders other than hemophilia = 16) were transfused with liquid cryoprecipitate, locally produced, lyophilized cryoprecipitate, imported from São Paulo (Brazil) and factor VIII and IX, imported from Rio de Janeiro (Brazil), Europe, and United States. Thirty six (22%) tested HIV seropositive. The univariate and multivariate analysis (logistic model) demonstrated that the risk of HIV infection during the study period was associated with the total units of acellular blood components transfused. In addition, the proportional contribution of the individual components to the total acellular units transfused, namely a increase in factor VIII/IX and lyophilized cryoprecipitate proportions, were found to be associated with HIV seropositivity. This analysis suggest that not only the total amount of units was an important determinant of HIV infection, but that the risk was also associated with the specific component of blood transfused.