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1.
BMC Genomics ; 19(1): 258, 2018 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-29661134

RESUMO

BACKGROUND: Prolongation of superstimulatory treatment appears to be associated with a greater superovulatory response and with greater oocyte maturation in cattle. A genome-wide bovine oligo-microarray was used to compare the gene expression of granulosa cells collected from ovarian follicles after differing durations of the growing phase induced by exogenous FSH treatment. Cows were given a conventional (4-day) or long (7-day) superstimulatory treatment (25 mg FSH im at 12-h intervals; n = 6 per group), followed by prostaglandin treatment with last FSH and LH treatment 24 h later. Granulosa cells were harvested 24 h after LH treatment. RESULTS: The expression of 416 genes was down-regulated and 615 genes was up-regulated in the long FSH group compared to the conventional FSH group. Quantification by RT-PCR of 7 genes (NTS, PTGS2, PTX3, RGS2, INHBA, CCND2 and LRP8) supported the microarrays data. Multigene bioinformatic analysis indicates that markers of fertility and follicle maturity were up-regulated in the long FSH group. CONCLUSION: Using the large gene expression dataset generated by the genomic analysis and our previous associated with the growth phase and gene expression changes post LH, we can conclude that a prolonged FSH-induced growing phase is associated with transcriptomic characteristics of greater follicular maturity and may therefore be more appropriate for optimizing the superovulatory response and developmental competence of oocytes in cattle.


Assuntos
Bovinos/genética , Hormônio Foliculoestimulante/farmacologia , Células da Granulosa/metabolismo , Transcriptoma/efeitos dos fármacos , Animais , Bovinos/metabolismo , Feminino , Hormônio Foliculoestimulante/administração & dosagem , Líquido Folicular/química , Perfilação da Expressão Gênica , Células da Granulosa/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real , Superovulação
2.
Reprod Fertil Dev ; 27(8): 1137-46, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24942058

RESUMO

Our objective was to study the effect of superstimulation protocols on nuclear maturation of the oocyte and the distribution of lipid droplets in the ooplasm. Heifers (n=4 each group) during the luteal phase were either treated with FSH for 4 days (Short FSH), FSH for 4 days followed by 84h of gonadotropin free period (FSH Starvation) or for 7 days (Long FSH) starting from the day of wave emergence. In all groups, LH was given 24h after induced luteolysis (penultimate day of FSH) and cumulus-oocyte complexes were collected 24h later. Oocytes were stained for nuclear maturation (Lamin/chromatin) and lipid droplets (Nile red). The Long FSH group had a greater proportion of mature oocytes (metaphase II) compared with heifers in the Short FSH and FSH Starvation groups (59/100 vs 5/23 and 2/25, respectively; P<0.01). On average across all groups, oocytes contained 22pL of lipids (3.3% of ooplasm volume) distributed as 3000 droplets. Average volume of individual lipid droplets was higher in the FSH Starvation (11.5±1.5 10(-3) pL, P=0.03) compared with the Short and Long FSH groups (7.2±0.6 10(-3) and 8.0±0.8 10(-3) pL, respectively). In conclusion, both FSH Starvation and Short FSH treatments yielded a lower proportion of mature oocytes compared with the Long FSH treatment. Furthermore, FSH starvation led to an accumulation of larger lipid droplets in the ooplasm, indicating atresia. Our results indicate that a longer superstimulation period in beef cattle yields higher numbers and better-quality oocytes.


Assuntos
Núcleo Celular/fisiologia , Gotículas Lipídicas/fisiologia , Oócitos/fisiologia , Indução da Ovulação/veterinária , Superovulação/fisiologia , Animais , Bovinos , Núcleo Celular/efeitos dos fármacos , Feminino , Hormônio Foliculoestimulante/farmacologia , Gotículas Lipídicas/efeitos dos fármacos , Hormônio Luteinizante/farmacologia , Oócitos/efeitos dos fármacos , Indução da Ovulação/métodos , Superovulação/efeitos dos fármacos
3.
Reproduction ; 146(2): 181-91, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23740080

RESUMO

Microarray analysis was used to compare the gene expression of granulosa cells from dominant follicles with that of those after superstimulatory treatment. Cows were allocated randomly to two groups (superstimulation and control, n=6/group). A new follicular wave was induced by ablation of follicles ≥5 mm in diameter, and a progesterone-releasing device controlled internal drug release (CIDR) was placed in the vagina. The superstimulation group was given eight doses of 25 mg FSH at 12-h intervals starting from the day of wave emergence (day 0), whereas the control group was not given FSH treatment. Both groups were given prostaglandin F2α twice, 12 h apart, on day 3 and the CIDR was removed at the second injection; 25 mg porcine luteinizing hormone (pLH) was given 24 h after CIDR removal, and cows were ovariectomized 24 h later. Granulosa cells were collected for RNA extraction, amplification, and microarray hybridization. A total of 190 genes were downregulated and 280 genes were upregulated. To validate the microarray results, five genes were selected for real-time PCR (NTS, FOS, THBS1, FN1, and IGF2). Expression of four genes increased significantly in the three different animals tested (NTS, FOS, THBS1, and FN1). The upregulated genes are related to matrix remodeling (i.e. tissue proliferation), disturbance of angiogenesis, apoptosis, and oxidative stress response. We conclude that superstimulation treatment i) results in granulosa cells that lag behind in maturation and differentiation (most of the upregulated genes are markers of the follicular growth stage), ii) activates genes involved with the NFE2L2 oxidative stress response and endoplasmic reticulum stress response, and iii) disturbs angiogenesis.


Assuntos
Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Células da Granulosa/efeitos dos fármacos , Indução da Ovulação/veterinária , Estresse Oxidativo/efeitos dos fármacos , Administração Intravaginal , Animais , Bovinos , Cruzamentos Genéticos , Preparações de Ação Retardada , Feminino , Fármacos para a Fertilidade Feminina/administração & dosagem , Fármacos para a Fertilidade Feminina/farmacologia , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Foliculoestimulante/farmacologia , Perfilação da Expressão Gênica/veterinária , Células da Granulosa/metabolismo , Injeções Intramusculares , Fator 2 Relacionado a NF-E2/biossíntese , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Progesterona/administração & dosagem , Progesterona/farmacologia , RNA Mensageiro/metabolismo , Distribuição Aleatória
4.
Reprod Fertil Dev ; 25(3): 523-30, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23464499

RESUMO

In the present study, we tested the hypotheses that oocyte competence is compromised by a longer duration of follicular growth and that it is not affected by FSH starvation. Cows were allocated to short FSH (n=14), FSH starvation (n=13) and long FSH (n=13) groups. The first two groups were given eight doses of FSH, whereas the third group was given 14 doses of FSH, starting from the day of wave emergence (Day 0). A progesterone-releasing device (controlled internal drug release; CIDR) was placed intravaginally at the start of the experiment in all groups. The short FSH group was given prostaglandin (PG) F2α on Day 3, whereas the two other groups received PGF2α on Day 6. In all cows, the CIDR was removed at the time of PGF treatment; porcine (p) LH was given 24h after CIDR removal and cows were inseminated 24 and 36 h later. Reproductive tracts were collected 4 days after insemination and ova and/or embryos were cultured for ≥6 days. The FSH starvation group had fewer ovulations (P=0.001), and ova and/or embryos (P<0.05). No difference in embryo quality was detected between long and short FSH groups at 7, 9 or 10 days after artificial insemination. In conclusion, oocyte competence was not altered by the duration of the follicular growth phase in superstimulated cows, whereas FSH starvation substantially reduced the ability of superstimulated follicles to ovulate.


Assuntos
Bovinos/fisiologia , Fármacos para a Fertilidade Feminina/administração & dosagem , Oócitos/efeitos dos fármacos , Oogênese/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Superovulação/efeitos dos fármacos , Animais , Cruzamentos Genéticos , Ectogênese/efeitos dos fármacos , Técnicas de Cultura Embrionária/veterinária , Implantação do Embrião/efeitos dos fármacos , Feminino , Fármacos para a Fertilidade Feminina/farmacologia , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Foliculoestimulante/farmacologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Inseminação Artificial/veterinária , Oócitos/citologia , Folículo Ovariano/citologia , Folículo Ovariano/diagnóstico por imagem , Gravidez , Distribuição Aleatória , Saskatchewan , Fatores de Tempo , Ultrassonografia
5.
Braz J Biol ; 83: e271425, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37341252

RESUMO

Medicinal plant species are genetically engineered to obtain higher production of biomass and specific secondary metabolites, which can be used in the pharmaceutical industry. The aim of the present study was to evaluate the effect of Pfaffia glomerata (Spreng.) Pedersen tetraploid hydroalcoholic extract on the liver of adult Swiss mice. The extract was prepared from the plant roots and given to the animals by gavage, for 42 days. The experimental groups were treated with water (control), Pfaffia glomerata tetraploid hydroalcoholic extract (100, 200 and 400 mg/kg) and Pfaffia glomerata tetraploid hydroalcoholic extract discontinuously (200 mg/kg). The last group received the extract every 3 days, for 42 days. The oxidative status, mineral dynamics, and cell viability were analysed. The liver weight and the number of viable hepatocytes were reduced, despite the increased cell's number. Increased levels of malondialdehyde and nitric oxide, and changes in iron, copper, zinc, potassium, manganese and sodium levels were observed. aspartate aminotransferase levels were increased while alanine aminotransferase levels were decreased due to BGEt intake. Our results showed that BGEt induced alterations of oxidative stress biomarkers leading to liver injury, which was associated with a reduction in the number of hepatocytes.


Assuntos
Amaranthaceae , Tetraploidia , Animais , Camundongos , Fígado , Estresse Oxidativo , Extratos Vegetais/toxicidade
6.
Domest Anim Endocrinol ; 81: 106729, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35462327

RESUMO

The objectives were to investigate the relationships between antral follicle counts and plasma AMH and FSH at the time of follicular wave emergence in prepubertal calves, and to determine the effects of age and duration of gonadotropin treatment on the ovarian superstimulatory response in pre- and post-pubertal heifers. Hereford crossbred prepubertal (Replicate 1 and 2, n = 20) and post-pubertal heifers (Replicates 1, n = 8; Replicate 2, n = 8) were assigned randomly to 2 treatment groups and given FSH for either 4 or 7 d (25 mg pFSH im at 12-h intervals). Prepubertal heifers were first treated at 4 mo and again at 7 mo of age. Blood samples were collected immediately before the first FSH administration, that was initiated 36 h after follicular ablation. An LH treatment (12.5 mg im) was given 12 h after the last FSH injection. Follicular fluid and cumulus-oocyte complexes (COC) were collected 24 h after LH treatment. At wave emergence, the number of follicles ≥1 mm (AFC, 31.1 ± 4.0 vs 16.2 ± 1.8; P < 0.001) and the plasma concentrations of AMH (606.4 ± 90.5 vs 279.6 ± 28.3 pg/mL; P = 0.001) were higher at 4 than at 7 mo of age, while plasma FSH concentrations did not differ between ages. At oocyte collection, a higher number of follicles ≥6 mm were observed in prepubertal calves at 4 mo of age and post-pubertal heifers than in calves at 7 mo of age (32.4 ± 5.4 and 22.0 ± 2.3 vs 14.9 ± 2.0, respectively; P = 0.003). Intrafollicular concentrations of estradiol were lower (23.7 ± 4.5 vs 144.0 ± 29.5 ng/mL; P < 0.0001) and of progesterone tended to be higher (217.5 ± 29.3 vs 157.0 ± 33.9 ng/mL; P = 0.07) in the 7- than in the 4-d groups. A greater number of COC was collected from calves at 4 mo of age and heifers than the 7-mo-old calves (13.4 ± 2.6 and 6.0 ± 1.0 vs 5.8 ± 1.1, respectively; P = 0.008). Overall, the 7-d FSH treatment tended to result in a greater proportion of expanded COC than the 4-d treatment in calves (50.1 ± 7.7 vs 31.9 ± 6.8%; P = 0.07). In summary, there was a positive relationship between AFC and plasma AMH concentrations at the time of wave emergence. A higher AFC was observed in calves at 4- than 7-mo of age, which resulted in greater ovarian response to gonadotropin treatment. Following an exogenous LH stimulus, COC maturation rates were greater in the 7-d than in the 4-d FSH treatment groups, resulting in collection of a higher proportion of fully expanded COC.


Assuntos
Hormônio Foliculoestimulante , Recuperação de Oócitos , Animais , Bovinos , Feminino , Recuperação de Oócitos/métodos , Recuperação de Oócitos/veterinária , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Ovário
7.
Osteoporos Int ; 21(5): 831-6, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19629615

RESUMO

UNLABELLED: Association between the presence of an elongated styloid process, vascular calcification (atheroma) and the potential risk factor for osteoporosis was studied. Presence of an elongated styloid process was found to be correlated with systemic osteoporosis and also between elongated styloid process and atheroma. INTRODUCTION: The association between the presences of an elongated styloid process and vascular calcification (atheroma) with the potential risk factor assessment for osteoporosis was studied. METHODS: Bone mineral density obtained by dual energy X-ray absorptiometry diagnosed osteopenia/osteoporosis on at least two of three sites (column, hips, and forearm) of 50 female patients. Panoramic maxillomandibular radiographs were taken and analyzed. Elongation of the styloid processes was measured and the presence of atheromas in the carotid was investigated. RESULTS: Eighty percent of the patients presented at least one side with elongated styloid process and the highest prevalence (87.5%) occurred in individuals between 60 and 69 years. Atheroma was found in four patients, three of which presented elongated styloid on at least one side and had diagnosed osteoporosis on at least two of the evaluated sites. CONCLUSIONS: Correlation was found between the elongation of the styloid process and systemic osteoporosis, and between elongated styloid process and atheroma. The method in this study might be used as part of a method for osteopenia/osteoporosis and atheroma risk assessment.


Assuntos
Doenças Ósseas Metabólicas/complicações , Placa Aterosclerótica/complicações , Absorciometria de Fóton , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Calcinose/complicações , Calcinose/diagnóstico por imagem , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Ossificação Heterotópica/complicações , Ossificação Heterotópica/diagnóstico por imagem , Osteoporose/complicações , Placa Aterosclerótica/diagnóstico por imagem , Radiografia Panorâmica , Osso Temporal/anormalidades , Osso Temporal/diagnóstico por imagem
8.
Histol Histopathol ; 35(10): 1135-1149, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32735026

RESUMO

Properties attributed to the Panax ginseng are also attributed to the Brazilian ginseng, such as adaptogenic and aphrodisiac effects. There are studies demonstrating that the Brazilian ginseng (BGE) possibly increases the serum levels of testosterone and nitric oxide in mice and rats. The present study aimed to evaluate the effects of its extract on male fertility and sperm quality. Male Swiss mice (n = 60) were divided into six groups. The control animals were provided 0.5 mL of water, and 0.5 mL of water containing 7 mg/kg per day (d) sildenafil citrate. Other animals were treated with BGE at 100 mg/kg/d, 200 mg/kg/d, and 400 mg/kg/d by gavage for 42 days. Finally, animals from the last group received 200 mg/kg BGE every 3 days (3-3d) by gavage for 42 days. The results showed a reduction in the number of resistant spermatids in the testis and damage to daily sperm production, culminating in a reduction in the number of epididymal spermatozoa. Although the sperm quality decreased in all experimental animals, only males treated with BGE 100 mg/kg/d showed pre and post implantation embryo losses. We concluded that BGE alters sperm viability compromising the embryonic development after implantation.


Assuntos
Panax , Extratos Vegetais/farmacologia , Reprodução/efeitos dos fármacos , Animais , Brasil , Epididimo/efeitos dos fármacos , Masculino , Camundongos , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Testosterona/metabolismo
9.
Anim Reprod Sci ; 149(1-2): 80-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25107564

RESUMO

The review presents an overview of studies that examined the effects of follicular aging and maternal aging in the bovine model. The first of three main sections is a discussion of the developmental competence of oocytes from (1) the ovulatory follicle of 2-wave and 3-wave estrous cycles, (2) dominant follicles that develop under high or low LH pulse frequency, and (3) natural versus FSH-stimulated ovulatory follicles. The second section highlights the effects of maternal aging. Maternal aging in cattle is associated with (1) elevated circulating FSH concentrations, (2) reduced response to superstimulatory treatment, and (3) markedly decreased early embryonic development in cows >12 year of age. The third and final section on superstimulation protocols addresses the effects of the duration of FSH stimulation and withdrawal (i.e., FSH "starvation" or "coasting") on oocyte competence. Ovarian superstimulation for 4 days altered the expression of genes related to angiogenesis, and activated oxidative stress-response genes. Extending the duration of FSH stimulation from 4 to 7 days resulted in a greater and more synchronous ovulatory response and optimal oocyte maturation. The highest rates of blastocyst development in vitro were obtained when FSH support was discontinued for 44 to 68h and granulosa cell SMAD7 mRNA was predictive of this period. Longer periods of FSH starvation resulted in a loss of oocyte competence or ovulatory capability. By extending the bovine model to the transcriptome level, new approaches and treatments may be devised to resolve subfertility in women and animals.


Assuntos
Células da Granulosa/fisiologia , Oócitos/fisiologia , Indução da Ovulação , Superovulação/fisiologia , Envelhecimento , Animais , Bovinos , Feminino , Humanos
10.
Braz J Med Biol Res ; 46(10): 839-43, 2013 10.
Artigo em Inglês | MEDLINE | ID: mdl-24141611

RESUMO

Paracoccidioidomycosis (PCM) is a chronic systemic mycosis caused by the inhalation of the thermally dimorphic fungus Paracoccidioides brasiliensis as well as the recently described P. lutzii. Because the primary infection occurs in the lungs, we investigated the differential involvement of the right and left lungs in experimental P. brasiliensis infection. Lungs were collected from C57BL/6 mice at 70 days after intravenous infection with 1×106 yeast cells of a virulent strain of P. brasiliensis (Pb18). The left lung, which in mice is smaller and has fewer lobes than the right lung, yielded increased fungal recovery associated with a predominant interleukin-4 response and diminished synthesis of interferon-γ and nitric oxide compared with the right lung. Our data indicate differential involvement of the right and left lungs during experimental PCM. This knowledge emphasizes the need for an accurate, standardized protocol for tissue collection during studies of experimental P. brasiliensis infection, since experiments using the same lungs favor the collection of comparable data among different mice.


Assuntos
Pneumopatias Fúngicas/microbiologia , Pulmão/microbiologia , Paracoccidioides , Paracoccidioidomicose/microbiologia , Animais , Modelos Animais de Doenças , Interferon gama/análise , Interleucina-10/análise , Interleucina-4/análise , Masculino , Camundongos Endogâmicos C57BL , Óxido Nítrico/análise , Fatores de Tempo
11.
Theriogenology ; 79(8): 1177-1183.e1, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23534995

RESUMO

We tested the hypotheses that extending the duration of follicular growth by superstimulation increases oocyte competence, and that FSH starvation at the end of superstimulatory treatment decreases oocyte competence. Heifers were randomly assigned to three groups: short FSH, FSH starvation, and long FSH (N = 8 per group). At 5 to 8 days after ovulation, follicle ablation was performed, and a progesterone-releasing device (CIDR) was placed intravaginally. Short FSH and FSH starvation groups were given eight doses of FSH im at 12-hour intervals, and the long FSH group was given 14 doses. PGF2α was administered twice (12 hours apart) and the CIDR was removed on Day 3 (Day 0 = wave emergence) in the short FSH group, and on Day 6 in the other two groups. Heifers were given LH 24 hours after CIDR removal and cumulus-oocyte complexes (COC) were collected 24 hours later. The COC were matured in vitro for 6 hours and fertilized in vitro; embryos were cultured for 10 days. A greater number of follicles ≥9 mm were detected in the long FSH group than in the FSH starvation and short FSH groups (25.4 ± 5.3, 11.0 ± 2.1, 10.6 ± 2.3, respectively; P < 0.03). A greater proportion of expanded COC were collected from the long FSH than from the FSH starvation group (P < 0.001), and the short FSH group was intermediate (93%, 54%, and 74%, respectively). The FSH starvation group had a greater proportion of poor quality oocytes than the short and long FSH groups (70%, 45%, and 33%, respectively; P < 0.001) and cleavage rate was lower (22%, 54%, and 56%, respectively; P = 0.003). The proportion of oocytes that developed into embryos (morulae and blastocysts on Day 9 after IVF) was also lower in the FSH starvation group than in the short and long FSH groups, (5% vs. 25% and 37%; P = 0.04); the latter two groups did not differ. The long FSH treatment resulted in 2.5 and 3.4 times more transferable embryos per animal (morulae and blastocysts) at Day 9 after IVF than the short FSH and FSH starvation groups (5.6, 2.5, and 1.7 embryos per heifer respectively; P = 0.04). In conclusion, extending the standard superstimulation protocol by 3 days enhanced the ovarian response to FSH treatment, and a period of FSH starvation after superstimulatory treatment compromised oocyte quality and the fertilization process.


Assuntos
Desenvolvimento Embrionário/fisiologia , Fase Folicular/fisiologia , Oócitos/fisiologia , Animais , Bovinos , Células Cultivadas , Esquema de Medicação , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Fármacos para a Fertilidade Feminina/administração & dosagem , Fármacos para a Fertilidade Feminina/farmacologia , Fertilização in vitro/veterinária , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Foliculoestimulante/deficiência , Hormônio Foliculoestimulante/farmacologia , Fase Folicular/efeitos dos fármacos , Técnicas de Maturação in Vitro de Oócitos/veterinária , Masculino , Recuperação de Oócitos/métodos , Recuperação de Oócitos/veterinária , Oócitos/citologia , Oócitos/efeitos dos fármacos , Superovulação/efeitos dos fármacos , Superovulação/fisiologia , Fatores de Tempo
12.
Theriogenology ; 77(2): 437-44, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-21975220

RESUMO

The objective was to determine the effects of the duration of progesterone exposure during the ovulatory wave on fertility (pregnancy rate) in beef cattle. We tested the hypothesis that short-progesterone exposure during the growing and early-static phase of the ovulatory follicle (analogous to the ovulatory wave of 3-wave cycles) is associated with higher fertility than a longer duration of exposure (analogous to the ovulatory wave of 2-wave cycles). Three to 5 days after ovulation, beef heifers (n = 172) and suckled beef cows (n = 193) were given an intravaginal progesterone-releasing device (CIDR) and 2.5 mg estradiol - 17ß +50 mg progesterone im to induce a new follicular wave. Cattle were allocated to short- or long-progesterone exposure groups (for 3 and 6 d after wave emergence, respectively) after which prostaglandin F(2α) was administered and CIDR were removed. Forty-eight hours later, all cattle were given 12.5 mg pLH and artificially inseminated (AI) with frozen-thawed semen. The diameter of the two largest follicles and the corpus luteum were measured by transrectal ultrasonography at CIDR removal, insemination, and 36 h after insemination. Pregnancy diagnosis was done ultrasonically 38 and 65 d post-AI. There was no difference in pregnancy rates in short- vs long-progesterone exposure in heifers (53 vs 47%, P = 0.44) or cows (63 vs 58%, P = 0.51). However, the diameter of the ovulatory follicle at CIDR removal and AI was smaller in short- than in long-progesterone groups (P < 0.02), and larger in cows than in heifers (P < 0.006). In conclusion, short-progesterone exposure during the growing and early-static phase of the ovulatory follicle (similar to 3-wave cycles) was not associated with higher fertility than a longer progesterone exposure (similar to 2-wave cycles).


Assuntos
Bovinos/fisiologia , Fertilidade/efeitos dos fármacos , Folículo Ovariano/fisiologia , Ovulação/fisiologia , Progesterona/administração & dosagem , Administração Intravaginal , Animais , Dinoprosta/administração & dosagem , Estradiol/administração & dosagem , Feminino , Inseminação Artificial/veterinária , Folículo Ovariano/diagnóstico por imagem , Folículo Ovariano/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Gravidez , Fatores de Tempo , Ultrassonografia
13.
Domest Anim Endocrinol ; 39(3): 155-62, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20580523

RESUMO

We examined whether progesterone (P4)-induced suppression of LH release in cattle can be overcome by an increased dose of exogenous gonadotropin-releasing hormone (GnRH) or pretreatment with estradiol (E2). In Experiment 1, postpubertal Angus-cross heifers (N = 32) had their 2 largest ovarian follicles ablated 5 d after ovulation. Concurrently, these heifers were all given a once-used, intravaginal P4-releasing insert (CIDR), and they were randomly assigned to be given either prostaglandin F(2alpha) (Low-P4) or no treatment (High-P4) at follicle ablation, and 12 h later. Six days after emergence of a new follicular wave, half of the heifers in each group (n = 8) were given either 100 or 200 microg of GnRH i.m. Plasma luteinizing hormone (LH) concentrations were higher in the Low- vs High-P4 groups, and in heifers given 200 vs 100 microg of GnRH (mean +/- SEM 15.4 +/- 2.2 vs 9.1 +/- 1.2, and 14.8 +/- 2.1 vs 9.8 +/- 1.4 ng/mL, respectively; P < or = 0.01). Ovulation rate was higher (P = 0.002) in the Low-P4 group (15/16) than in the High-P4 group (6/16), but it was not affected by GnRH dose (P = 0.4). In Experiment 2, heifers (n = 22) were treated similarly, except that 5.5 d after wave emergence, half of the heifers in each group were further allocated to be given either 0.25 mg estradiol benzoate i.m. or no treatment, and 8 h later, all heifers were given 100 microg GnRH i.m. Both groups treated with E2 (Low- and High-P4) and the Low-P4 group without E2 had higher peak plasma LH concentrations compared to the group with high P4 without E2 (12.6 +/- 1.8, 10.4 +/- 1.8, 8.7 +/- 1.3, and 3.9 +/- 1.2 ng/mL, respectively; (P < 0.04)). However, E2 pretreatment did not increase ovulation rates in response to GnRH (P = 0.6). In summary, the hypotheses that higher doses of GnRH will be more efficacious in inducing LH release and that exogenous E2 will increase LH release following treatment with GnRH were supported, but neither significantly increased ovulation rate.


Assuntos
Bovinos/fisiologia , Estradiol/administração & dosagem , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Luteinizante/metabolismo , Progesterona/sangue , Animais , Dinoprosta/administração & dosagem , Feminino , Hormônio Luteinizante/sangue , Folículo Ovariano/fisiologia , Ovulação/efeitos dos fármacos , Progesterona/administração & dosagem
15.
Braz. j. med. biol. res ; 46(10): 839-843, 24/set. 2013. graf
Artigo em Inglês | LILACS | ID: lil-688562

RESUMO

Paracoccidioidomycosis (PCM) is a chronic systemic mycosis caused by the inhalation of the thermally dimorphic fungus Paracoccidioides brasiliensis as well as the recently described P. lutzii. Because the primary infection occurs in the lungs, we investigated the differential involvement of the right and left lungs in experimental P. brasiliensis infection. Lungs were collected from C57BL/6 mice at 70 days after intravenous infection with 1×106 yeast cells of a virulent strain of P. brasiliensis (Pb18). The left lung, which in mice is smaller and has fewer lobes than the right lung, yielded increased fungal recovery associated with a predominant interleukin-4 response and diminished synthesis of interferon-γ and nitric oxide compared with the right lung. Our data indicate differential involvement of the right and left lungs during experimental PCM. This knowledge emphasizes the need for an accurate, standardized protocol for tissue collection during studies of experimental P. brasiliensis infection, since experiments using the same lungs favor the collection of comparable data among different mice.


Assuntos
Animais , Masculino , Pneumopatias Fúngicas/microbiologia , Pulmão/microbiologia , Paracoccidioides , Paracoccidioidomicose/microbiologia , Modelos Animais de Doenças , Interferon gama/análise , /análise , /análise , Óxido Nítrico/análise , Fatores de Tempo
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