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1.
MedEdPORTAL ; 17: 11197, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34765724

RESUMO

INTRODUCTION: MedEdPORTAL is an open-access journal for health professions educators to publish their educational activities. The Educational Summary Report (ESR) is the manuscript that represents scholarly expression of those activities, aligned with Glassick's criteria for scholarship; however, prospective authors face challenges in writing ESRs, which can lead to rejection. METHODS: We developed a conference workshop to teach health professions educators how to write an ESR by reviewing a sample ESR in small groups. The workshop began with a didactic on best practices in crafting each section of an ESR. We then divided participants into small groups to review an assigned section of a sample ESR using a reviewer's checklist and completing a templated flip chart. Each small group then reported out in a large-group discussion. A conference evaluation was distributed online to solicit perceptions of the workshop's effectiveness. RESULTS: The 90-minute workshop was presented by separate teams of two facilitators at three national conferences. Approximately 35 participants attended the first workshop, and 50 attended the second and third workshops. Survey feedback from 19 respondents (38%) to the evaluation survey at the third workshop was representative of the previous two iterations and demonstrated that workshop content and materials were helpful. DISCUSSION: A workshop enabling educators to serve as group peer reviewers of a sample ESR for a MedEdPORTAL submission was well received. Associate editors, faculty mentors, and other experienced faculty development leaders can use these materials to support future authors in submitting to MedEdPORTAL while providing opportunities for national presentations.


Assuntos
Educação Médica , Relatório de Pesquisa , Bolsas de Estudo , Humanos , Estudos Prospectivos , Editoração
3.
J Am Vet Med Assoc ; 231(12): 1864-7, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-18081527

RESUMO

OBJECTIVE: To determine whether IM administration of exogenous oxytocin twice daily on days 7 to 14 after ovulation blocks luteolysis and causes prolonged function of corpora lutea (CL) in mares. DESIGN: Prospective study. ANIMALS: 12 mares. PROCEDURES: Beginning on the day of ovulation (day 0), jugular blood samples were collected every other day until day 40 for determination of progesterone concentration. On day 7, mares (n = 6/group) were treated with saline (0.9% NaCl) solution (control group) or oxytocin. Beginning on day 7, control mares received 3 mL of sterile saline solution every 12 hours, IM, and oxytocin-treated mares received 60 units of oxytocin every 12 hours, IM, through day 14. Mares were considered to have prolonged CL function if progesterone concentration remained > 1.0 ng/mL continuously through day 30. RESULTS: The proportion of mares with prolonged CL function was significantly higher in the oxytocin-treated group (6/6), compared with the control group (0/6). All control mares underwent luteolysis by day 16, at which time their progesterone concentrations were < 1.0 ng/mL. In contrast, all 6 oxytocin-treated mares maintained progesterone concentrations > 1.0 ng/mL continuously through day 30. CONCLUSIONS AND CLINICAL RELEVANCE: IM administration of 60 units of oxytocin twice daily on days 7 to 14 after ovulation was an efficacious method of inhibiting luteolysis and extending CL function in mares. Disrupting luteolysis by administering exogenous oxytocin during diestrus appears to be a plausible and practical method of long-term suppression of estrus in mares.


Assuntos
Corpo Lúteo , Cavalos/fisiologia , Luteólise/efeitos dos fármacos , Ocitócicos/farmacologia , Ocitocina/farmacologia , Progesterona/sangue , Animais , Área Sob a Curva , Corpo Lúteo/efeitos dos fármacos , Corpo Lúteo/fisiologia , Diestro/efeitos dos fármacos , Diestro/fisiologia , Feminino , Cavalos/sangue , Injeções Intramusculares/veterinária , Luteólise/fisiologia , Ovulação , Estudos Prospectivos
4.
Reprod Fertil Dev ; 18(1-2): 91-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16478606

RESUMO

Cloning is one of several new assisted reproductive techniques being developed for clinical use in the equine industry. Potential uses of equine cloning include: (1) the preservation of genetics from individual animals that would otherwise not be able to reproduce, such as geldings; (2) the preservation of genetic material of endangered and/or exotic species, such as the Mongolian wild horse (Przewalski's horse); and (3) because of the companion animal role that horses fill for some individuals, it is likely that some horse owners will have individual animals cloned for emotional fulfillment. Although equine cloning has been successful, like other species, it remains a very inefficient process (<3% success). In most species, the inefficiency of cloning results from a high incidence of embryonic, fetal and/or placental developmental abnormalities that contribute to extremely high rates of embryonic loss, abortion and stillbirths throughout gestation and compromised neonatal health after birth. The present review describes some of the ultrasonographic, endocrinological and histopathological characteristics of successful (produced viable offspring) and unsuccessful (resulted in pregnancy failure) cloned equine (mule and horse) pregnancies we have produced. A total of 21 cloned mule pregnancies were established using fetal fibroblast cells, whereas a total of seven cloned horse pregnancies were established using adult cumulus cells. Three of the cloned mule conceptuses were carried to term, resulting in the birth of three healthy clones. This information adds to an accumulating body of knowledge about the outcome of cloned equine pregnancies, which will help to establish when, and perhaps why, many cloned equine pregnancies fail.


Assuntos
Clonagem de Organismos/métodos , Sistema Endócrino/metabolismo , Cavalos/fisiologia , Aborto Espontâneo , Animais , Animais Recém-Nascidos , Animais Selvagens , Equidae/fisiologia , Feminino , Masculino , Placenta/diagnóstico por imagem , Gravidez , Ultrassonografia Pré-Natal
5.
J Am Vet Med Assoc ; 228(2): 248-50, 2006 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-16426200

RESUMO

OBJECTIVE: To determine whether performance of transvaginal ultrasound-guided follicle aspiration (TVUFA) repeatedly in mares adversely affects their fertility. DESIGN: Historical prospective study. ANIMALS: 23 mares that had never undergone TVUFA and 59 mares that had undergone TVUFA on 1 to 11 occasions. PROCEDURE: Mares were classified into 4 groups according to the number of TVUFA procedures previously performed on the ovary in which ovulation occurred at the time of insemination as follows: group 1, 0 TVUFAs (control group, n = 23 mares); group 2, 1 or 2 TVUFAs (40 mare-cycles); group 3, 3 or 4 TVUFAs (21 mare-cycles); and group 4, 5 to 11 TVUFAs (13 mare-cycles). Each ovary and its associated number of TVUFAs were considered separately; therefore, some of the mares that underwent TVUFA were represented in > 1 group (1 mare was included in group 2 twice [once for each ovary]), and the sample size in groups 2, 3, and 4 was denoted as mare-cycles. Fertility was assessed as pregnancy rates in cycles in which mares were inseminated with fresh or cooled semen from 1 fertile stallion. RESULTS: There were no significant differences in pregnancy rates among groups 1, 2, 3, and 4 (83%, 90%, 81%, and 85%, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that repeated performance of TVUFA (as many as 11 times) had no detectable adverse effect on fertility in mares. This finding is clinically important for situations when TVUFA is performed on fertile mares, whether for oocyte collection or other purposes.


Assuntos
Fertilidade , Cavalos/fisiologia , Folículo Ovariano/fisiologia , Ultrassonografia/veterinária , Vagina/diagnóstico por imagem , Animais , Feminino , Inseminação Artificial/veterinária , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Ultrassonografia/efeitos adversos
6.
Reprod Fertil Dev ; 17(6): 651-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16263071

RESUMO

The in vitro maturation (IVM) of equine oocytes is typically performed using various synthetic media; however, an optimal IVM system for equine oocytes has not been developed. The aim of the present study was to evaluate the effects of two types of follicular fluid (FF) obtained from cyclic mares and two incubation intervals for the IVM of equine cumulus-oocyte complexes (COCs). Follicular fluid was collected from medium-sized (20-29 mm diameter) and large (e30 mm; post-human chorionic gonadotrophin administration) follicles using transvaginal ultrasound-guided follicle aspiration. Compact (n = 232) and non-compact (n = 183) COCs obtained from a slaughterhouse were incubated separately in the following groups: (1) FF from medium follicles for 24 h; (2) FF from large follicles for 24 h; (3) control (synthetic) medium for 24 h; (4) FF from medium follicles for 24 h then FF from large follicles for an additional 24 h; (5) FF from large follicles for 48 h; and (6) control medium for 48 h. For compact COCs, there was a tendency (P = 0.06) for more COCs incubated in FF from large follicles for 24 h to reach metaphase II compared with those incubated in control medium for 24 h (58% v. 35%, respectively). More (P < 0.05) compact COCs had degenerated after incubation in control medium for 48 h compared with all other groups (51% v. 14-24%, respectively). For non-compact COCs, incubation in FF from medium follicles for 24 h resulted in more (P = 0.05) COCs at metaphase II compared with control medium for 48 h (58% v. 29%, respectively). These results indicate that homologous FF from cyclic mares is a suitable alternative for the IVM of equine COCs and that it may be superior to conventional media for longer (i.e. >24 h) incubation intervals.


Assuntos
Líquido Folicular/fisiologia , Folículo Ovariano/fisiologia , Ovário/citologia , Animais , Núcleo Celular/genética , Núcleo Celular/fisiologia , Tamanho Celular , Células Cultivadas , Gonadotropina Coriônica/farmacologia , Feminino , Cavalos , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos
9.
Reprod Fertil Dev ; 16(7): 675-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15740690

RESUMO

The objectives of the present study were to: (1) clone horses using adult cumulus cells; and (2) determine whether the cumulus cell donor affected the outcome. In vivo-matured cumulus-oocyte complexes were obtained using transvaginal ultrasound-guided follicle aspiration; oocytes were used as cytoplasts, whereas cumulus cells (from one of three different mares) were used as donor cells. Immediately following nuclear transfer and activation procedures, cloned embryos were transferred surgically to the oviduct of recipient mares (n = 2-5 embryos per recipient) that had ovulated within 24 h prior to the transfer. An initial pregnancy examination was performed between Days 14 and 16 (Day 0 = surgery); subsequent examinations were then performed every 7-10 days. A total of 136 follicles were aspirated in 96 mares, from which 72 oocytes were recovered (53%). Sixty-two cloned embryos were transferred to recipient mares, which resulted in seven (11.3%) ultrasonographically detectable conceptuses between Days 14 and 16. All seven conceptuses were lost spontaneously between Days 16 and 80. Cumulus cells from Mare 160 tended (P = 0.08) to result in a higher embryo survival rate than cumulus cells from Mare 221 (4/17 v. 1/25 respectively). To our knowledge, this is the first report documenting the establishment of cloned equine pregnancies derived from adult cumulus cells.


Assuntos
Clonagem de Organismos , Cavalos , Folículo Ovariano/citologia , Animais , Núcleo Celular , Células Cultivadas , Senescência Celular , Perda do Embrião , Transferência Embrionária , Feminino , Técnicas de Transferência Nuclear , Oócitos , Gravidez
11.
J Am Vet Med Assoc ; 222(8): 1108-10, 2003 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-12710775

RESUMO

OBJECTIVE: To determine the effect on fertility of large-volume uterine lavage with lactated Ringer's solution (LRS) performed immediately prior to insemination in mares. DESIGN: Prospective randomized controlled study. ANIMALS: 20 mares. PROCEDURE: Control mares (n = 10) were inseminated with 1 billion (estimated before cooling) progressively motile spermatozoa that had been cooled in a passive cooling unit for 24 hours. Mares (n = 10) in the treatment group were inseminated with 1 billion progressively motile spermatozoa (cooled as described for control mares) immediately after uterine lavage with 4 L of sterile LRS. RESULTS: There were no significant differences in pregnancy rates or size of the embryonic vesicle on days 12, 13, and 14 after ovulation between control and treated mares. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that uterine lavage with LRS can be performed immediately prior to insemination without adversely affecting fertility in mares. This is clinically important, because insemination may be necessary when a mare has inflammation-associated fluid (detectable ultrasonographically) in the uterus; removal of the fluid is desirable, because it adversely affects spermatozoal motility and fertility. This situation typically arises when mares require rebreeding after they have developed persistent mating-induced endometritis or are inseminated multiple times in a 24-hour period (during the period of physiologic mating-induced inflammation), which is a common practice when using cooled or frozen-thawed semen.


Assuntos
Fertilidade , Cavalos/fisiologia , Inseminação Artificial/veterinária , Útero/fisiologia , Animais , Endometrite/fisiopatologia , Endometrite/veterinária , Feminino , Fertilidade/fisiologia , Doenças dos Cavalos/fisiopatologia , Soluções Isotônicas/administração & dosagem , Soluções Isotônicas/efeitos adversos , Masculino , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Distribuição Aleatória , Lactato de Ringer , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Irrigação Terapêutica/efeitos adversos , Irrigação Terapêutica/veterinária , Útero/patologia
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