Effects of Pasturella Multocida B: 2 and its immunogens (LPS and OMP) on reproductive hormones in Nili-Ravi Buffaloes / Efeitos de Pasteurella multocida B: 2 e seus imunógenos (LPS e OMP) em hormônios reprodutivos em búfalos Nili-Ravi

Abstract Livestock is a fundamental part of the agriculture industry in Pakistan and contributes more than 11.53% to GDP. Among livestock species, the buffaloes are regarded as the black gold of Pakistan. Being the highest milk producers globally, Nili-Ravi buffaloes are the most famous ones. Buffaloes are affected by many endemic diseases, and "Hemorrhagic septicemia" (HS) is one of them. This study was designed to ascertain the effects of experimental exposure ofP. multocida B:2 (oral) and its immunogens, i.e., LPS (oral and intravenous) and OMP (oral and subcutaneous) on reproductive hormonal profiles in Nili-Ravi buffaloes. Repeated serum samples were collected from the jugular vein of experimental animals for 21 days (0, 02, 04, 08, 12, 16, 20, 24, 36, 48, 72, 120, 168, 216, 264, 360, 456 and 504 hours). Hormonal assays to determine the serum concentrations of Gonadotropin-releasing hormone (GnRH), Follicle-stimulating hormone (FSH), Luteinizing hormone (LH), Estrogen (E2) and progesterone (P4) were performed using (MyBioSource) commercial Elisa kits. The hormonal profile of all treatment groups of the buffalo heifers exhibited significant (P<0.05) variations as compared to the control group (G-1). These results indicate suppression in Nili-Ravi buffaloes' reproductive hormonal profile on exposure to P. multocida B:2 and its immunogens. This influence warrants that exposure to H.S may be a possible reason for delayed puberty and poor reproduction performance in Nili-Ravi buffaloes.

Resumo A pecuária é uma parte fundamental da indústria agrícola no Paquistão e contribui com 11,53% do PIB nacional. Entre as espécies de gado, os búfalos são considerados o ouro negro do Paquistão. Sendo os maiores produtores de leite em todo o mundo, os búfalos Nili-Ravi são os mais famosos. Os búfalos são afetados por muitas doenças endêmicas, entre as quais a "septicemia hemorrágica" (SH). Este estudo busca verificar os efeitos da exposição experimental de P. multocida B:2 (oral) e seus imunógenos, ou seja, LPS (oral e intravenoso) e OMP (oral e subcutâneo), nos perfis hormonais reprodutivos em búfalos Nili-Ravi. Amostras de soro repetidas foram coletadas da veia jugular de animais experimentais por 21 dias (0, 2, 4, 8, 12, 16, 20, 24, 36, 48, 72, 120, 168, 216, 264, 360, 456 e 504 horas). Os ensaios hormonais para determinar as concentrações séricas do hormônio liberador de gonadotrofina (GnRH), hormônio foliculoestimulante (FSH), hormônio luteinizante (LH), estrogênio (E2) e progesterona (P4) foram realizados usando kits comerciais Elisa (MyBioSource). O perfil hormonal de todos os grupos de tratamento das novilhas bubalinas apresentou variações significativas (P < 0,05) em relação ao grupo controle (G-1). Esses resultados indicam supressão no perfil hormonal reprodutivo de búfalos Nili-Ravi na exposição a P. multocida B:2 e seus imunógenos. Essa influência garante que a exposição à SH possa ser uma possível razão para o atraso da puberdade e o baixo desempenho reprodutivo em búfalos Nili-Ravi.

Contraindicated use of modern contraceptives among mothers from a Pelotas Birth Cohort

ABSTRACT OBJECTIVE To describe the prevalence of contraindicated use of combined hormonal contraceptives, progesterone-only contraceptives, and intrauterine devices in mothers participating in the 2015 Pelotas Birth Cohort according to the WHO medical eligibility criteria. METHODS The biological mothers of children belonging to the 2015 Pelotas birth cohort who attended the 48-month follow-up were studied. The 48-month follow-up data were collected from January 1, 2019, to December 31, 2019. Contraindicated use of modern contraceptives was considered to occur when these women presented at least one of the contraindications for the use of modern contraceptives and were using these methods. The prevalence of contraindicated use was calculated according to each independent variable and their respective 95% confidence intervals (95%CI). RESULTS The analyzed sample consisted of 3,053 women who used any modern contraceptive method. The prevalence of contraindicated use of modern contraceptives totaled 25.9% (95%CI: 24.4-27.5). Combined hormonal contraceptives showed the highest prevalence of contraindicated use (52.1%; 95%CI: 49.3-54.8). The prevalence of contraindicated use of modern contraceptives methods was greater in women with family income between one and three minimum wages, a 25-30 kg/m2 body mass index, indication by a gynecologist for the used method, and purchasing the contraceptive method at a pharmacy. The higher the women's education, the lower the prevalence of inappropriate use of modern contraceptives. CONCLUSION In total, one in four women used modern contraceptives despite showing at least one contraindication. Policies regarding women's reproductive health should be strengthened.

Menopausia quirúrgica en pacientes con mutación BRCA, el papel de la terapia hormonal / Surgical Menopause in Patients with BRCA Mutation, the Role of Hormone Therapy

Introducción: las mujeres con mutación BRCA1/2 (mBRCA) tienen un riesgo aumentado de desarrollar cáncer de mama (CM) y ovario (CO). La salpingo-oforectomía bilateral (SOB) se asocia con la reducción del riesgo del 80% para CO y un 50% para CM. Se recomienda realizarla entre los 35 y 40 años. Como consecuencia se produce una menopausia prematura, con un impacto negativo sobre la calidad de vida por la presencia de síntomas climatéricos, aumento del riesgo de enfermedad cardiovascular, osteoporosis y riesgo de alteración cognitiva. La terapia hormonal (THM) es el tratamiento más eficaz para la prevención de estos síntomas. Estado del arte: distintos estudios han demostrado un mayor riesgo de CM en mujeres posmenopáusicas que reciben THM en particular con terapia combinada, estrógeno + progesterona (E+P). Según el metanálisis de Marchetti y cols., en las mujeres portadoras de mBRCA que recibieron THM, no hubo diferencias en el riesgo de CM comparando E solo con E+P. En el estudio de Kotsopoulos, incluso se encontró un posible efecto protector en aquellas que usaron E solo. Otro estudio en portadoras sanas demostró que, en las mujeres menores de 45 años al momento de la SOB, la THM no afectó las tasas de CM. Sin embargo, en las mujeres mayores de 45 años, las tasas de CM fueron más altas. Como el esquema de E+P se asocia con un mayor riesgo relativo (RR) de CM, las dosis de progestágenos utilizados se deberían limitar, eligiendo derivados naturales de progesterona, de uso intermitente para disminuir la exposición sistémica. Según diferentes guías internacionales, a las portadoras de mBRCA sanas que se someten a una SOB se les debe ofrecer THM hasta la edad promedio de la menopausia. Conclusión: la menopausia prematura disminuye la expectativa de vida; es por ello que una de las herramientas para mejorar y prevenir el deterioro de la calidad de vida es la THM. El uso de THM a corto plazo parece seguro para las mujeres portadoras de mBRCA que se someten a una SOB antes de los 45 años, al no contrarrestar la reducción del riesgo de CM obtenida gracias a la cirugía. (AU)

Introduction: women with BRCA1/2 (mBRCA) mutation have an increased risk of developing breast (BC) and ovarian (OC) cancer. Bilateral salpingo-oophorectomy (BSO) is associated with an 80% risk reduction for OC and 50% for BC. The recommended age for this procedure is 35 to 40 years. The consequence is premature menopause, which hurts the quality of life due to the presence of climacteric symptoms, increased risk of cardiovascular disease, osteoporosis, and a higher risk of cognitive impairment. Hormone therapy (MHT) is the most effective treatment for preventing these symptoms. State of the art: different studies have shown an increased risk of BC in postmenopausal women receiving MHT, particularly with combined therapy, estrogen + progesterone (E+P). According to the meta-analysis by Marchetti et al., in women carrying mBRCA who received MHT, there was no difference in the risk of BC compared to E alone with E+P. In the Kostopoulos study, there was also a possible protective effect in those who used E alone. Another study in healthy carriers showed that in women younger than 45 years at the time of BSO, MHT did not affect BC rates. However, in women older than 45 years, BC rates were higher. As the E+P scheme is associated with a higher RR of BC, the doses of progestogens should be limited, choosing natural progesterone byproducts of intermittent use to decrease systemic exposure. According to various international guidelines, healthy mBRCA carriers undergoing BSO should be offered MHT until the average age of menopause. Conclusion: premature menopause decreases life expectancy, which is why one of the tools to improve and prevent deterioration of quality of life is MHT. Short-term use of MHT appears safe for women with mBRCA who undergo BSO before age 45 as it does not counteract the reduction in the risk of MC obtained by surgery. (AU)

O uso de métodos contraceptivos hormonais em pacientes com asma: repercussões clínicas / The use of hormonal contraceptives methods in patients with asthma: clinical repercussions

Objetivo: Analisar o uso dos contraceptivos hormonais em mulheres com asma e a escolha desses métodos contraceptivos para essa população, com avaliação de eventuais repercussões sobre novos episódios de asma e sibilos. Métodos: Foram selecionados estudos longitudinais, ensaios clínicos, revisões sistemáticas e metanálises. As plataformas consultadas foram PubMed, Embase, Cochrane e SciELO, com a utilização dos descritores: "contracepção", "contracepção hormonal", "sistema intrauterino liberador de levonorgestrel" e "asma". Resultados: Dois grandes estudos demonstraram que o uso de contraceptivos hormonais esteve associado à redução do risco de novos episódios de asma. Uma revisão sistemática concluiu que os resultados para o uso de contraceptivos hormonais para mulheres com asma foram mistos, com aumento ou redução dos seguintes riscos: novo episódio de asma e aumento da frequência das crises e dos sibilos. O uso da contracepção hormonal em pacientes obesas portadoras de asma é controverso. Conclusão: Os resultados para o uso de contraceptivos hormonais em mulheres com asma são inconsistentes, com relatos de aumento ou de redução do risco de novos episódios. O uso do método contraceptivo deve ser discutido individualmente, levando-se em consideração outros fatores de risco associados e o desejo da mulher. A paciente deverá ser orientada se houver piora dos sintomas clínicos de asma na vigência do uso de qualquer método contraceptivo hormonal.

Objective: To analyze the use of hormonal contraceptives in women with asthma and the choice of this contraceptive method for this population, evaluating possible repercussions on new episodes of asthma and wheezing. Methods: Longitudinal studies, clinical trials, systematic reviews and meta-analyses were selected. Platforms consulted: PubMed, Embase, Cochrane, SciELO, using the descriptors: "contraception", "hormonal contraception", "levonorgestrel-releasing intrauterine system" and "asthma". Results: Two large studies demonstrated that the use of hormonal contraceptives was associated with a reduced risk of new episodes of asthma. A systematic review concluded that the results for the use of hormonal contraceptives for women with asthma were mixed, with increased or decrease in the following risks: new asthma episodes, increased frequency and wheezing. The use of hormonal contraception in obese patients with asthma is controversial. Conclusion: The results for the use of hormonal contraceptives in women with asthma are inconsistent, with reports of increased or reduced risk of new episodes. The use of the contraceptive method should be discussed individually, taking into account other associated risk factors and the woman's desire. The patient will be advised if there is a worsening of the clinical symptoms of asthma while using any hormonal contraceptive method.

Postnatal Exposure to Exogenous progesterone Exacerbates the Prenatally-Induced Abnormal Sperms Production and Function in Rats / La exposición Posnatal a la Progesterona Exógena Exacerba la Producción y Función Anormales de Espermatozoides Inducidas Prenatalmente en Ratas

SUMMARY: This study aimed at clarifying the impact of long-term prenatal and postnatal exposure to exogenous progesterone on sperm production and function, relative sex organs weights, and the levels of the relevant hormones in rats. Sixty male Wistar rats were included and classified into three groups (n=20 in each). A test I group had mature rats born to dams treated with progesterone prenatally. A test II group included rats exposed to progesterone during prenatal as well as postnatal periods, and a control group had rats treated with a placebo (olive oil). The test groups revealed a significant reduction in sperm count, motility, and viability with higher abnormal forms than the control group (P< 0.05). Similarly, the test groups revealed significantly lower serum testosterone and higher FSH and LH levels (P< 0.001). Interestingly, the test II group showed pronounced sperm abnormalities, an alarming decrease in sperm viability and motility, and a significant accretion in the relative testicular weight compared to the test I group (p <0.001). Long-term (prenatal and early postnatal) treatment with synthetic progesterone hurts sperm quantity and quality, adversely affecting future male fertility.

Este estudio tuvo como objetivo aclarar el impacto de la exposición prenatal y posnatal a largo plazo a la progesterona exógena en la producción y función de los espermatozoides, el peso relativo de los órganos sexuales y los niveles de las hormonas relevantes en ratas. Sesenta ratas macho Wistar fueron incluidas y clasificadas en tres grupos (n=20 en cada uno). Un grupo de prueba I tenía ratas maduras nacidas de madres tratadas con progesterona prenatalmente. Un grupo de prueba II incluyó ratas expuestas a progesterona durante los períodos prenatal y posnatal, y un grupo de control tenía ratas tratadas con un placebo (aceite de oliva). Los grupos de prueba revelaron una reducción significativa en el recuento, la motilidad y la viabilidad de los espermatozoides con formas anormales más altas que el grupo de control (P < 0,05). De manera similar, los grupos de prueba revelaron niveles significativamente más bajos de testosterona sérica y niveles más altos de FSH y LH (P < 0.001). Curiosamente, el grupo de prueba II mostró anormalidades espermáticas pronunciadas, una disminución alarmante en la viabilidad y motilidad de los espermatozoides y una acumulación significativa en el peso testicular relativo en comparación con el grupo de prueba I (p <0.001). El tratamiento a largo plazo (prenatal y posnatal temprano) con progesterona sintética daña la cantidad y la calidad del esperma, lo que afecta negativamente la futura fertilidad masculina.

Immunofluorescence Analysis of Estrogen and Progesterone Receptors and Ki-67 Nuclear Protein in Canine Uteri Treated with Medroxyprogesterone Acetate During Anestrus / Análisis de Inmunofluorescencia de Receptores de Estrógeno y Progesterona y Proteína Nuclear Ki-67 en Úteros Caninos Tratados con Acetato de Medroxiprogesterona Durante el Anestr

SUMMARY: Estradiol and progesterone receptors play an essential role in the changes occurring in the uterus during the estrus cycle in dogs (Canis lupus familiaris). In order to investigate the potential effect of progestational agent medroxyprogesterone acetate (MPA) when is used during anestrus on the expression of estradiol receptors [ER], progesterone receptors [PR] and nuclear protein Ki67, we evaluated uterine tissue immunohistochemically. Uteri were grouped as nulliparous (control, n=11), multiparous (n=11) and treated with MPA (n=11; nulliparous with two treatments; 5mg/kg; i.m.). The amount and location of PR, ER and Ki67 were studied on the epithelial surface, apical and basal regions of the endometrium and myometrium using immunohistochemical techniques with a spectral confocal microscope and analyzed by ANOVA. Differences in ER were observed between the multiparous and MPA-treated groups in the apical region of the endometrium (p=0.0022). Differences in cell proliferation were detected between the nulliparous and multiparous groups (p=0.0037) and nulliparous and MPA-treated groups (p=0.0003) in the basal region of the endometrium. In conclusion, two doses of MPA (5mg/kg; i.m.) do not have a significant effect on the expression of ER and PR; however, they inhibit cell proliferation in the basal region of the endometrium, which includes the stroma, subepithelial cell layer, compact layer, and spongy layer. The clinical and long-term effect of this treatment should be evaluated in subsequent studies.

Los receptores de estradiol y progesterona juegan un rol fundamental en los cambios que se producen en el útero durante el ciclo estral de las perras (Canis lupus familiaris). El objetivo de este estudio fue evaluar las expresiones de ER-a y PR en el útero y la proliferación de células endometriales detectando la expresión nuclear de la proteína Ki67 en perras expuestas a la progestina sintética MPA y compararlas con perras nulíparas y multíparas expuestas a progesterona luteal. Úteros fueron agrupados como nulíparas (control, n=11), multíparas (n=11) y tratadas con MPA (n=11; nulíparas con dos tratamientos; 5 mg/kg; i.m.). La expresión de PR, ER-a y Ki67 fue evaluada en la regiones apicales y basales del endometrio y miometrio con un microscopio confocal espectral. Se observó diferencias en ER-a entre los grupos multíparas y tratados con MPA en la región apical del endometrio (p=0,0022). Se detectaron diferencias en la proliferación celular entre los grupos de nulíparas y multíparas (p=0,0037) y los grupos de nulíparas y tratados con MPA (p=0,0003) en la región basal del endometrio. En conclusión, dos dosis de MPA (5mg/kg; i.m.) no tienen un efecto significativo sobre la expresión de ER y PR; sin embargo, inhiben la proliferación celular en la región basal del endometrio, el cual incluye a estroma, capa de células subepiteliales, estratos compacto y esponjoso. El efecto clínico a largo plazo de este tratamiento debe ser evaluado en estudios posteriores.

Perda gestacional de repetição e o papel dos progestagênios: evidências atuais / Recurrent pregnancy loss and the role of progestagens: current evidence

Objetivo: Discutir o uso dos progestagênios em mulheres com perda gestacional de repetição (PGR) sem causa aparente, abordando tipos de progestagênios e resultados de ensaios clínicos, revisões sistemáticas e metanálises. Métodos: Trata-se de uma revisão não sistemática de artigos publicados nas bases eletrônicas PubMed, Cochrane e SciELO nos últimos cinco anos, utilizando-se os seguintes descritores: "progesterone", "dydrogesterone", "recurrent pregnancy loss" e "recurrent abortion". Resultados: Duas grandes metanálises encontraram uma redução da taxa de abortamento e aumento da taxa de nascidos vivos com o uso do progestágeno sintético em pacientes com PGR inexplicada, porém essa conclusão foi contestada em uma metanálise mais recente. Entretanto, a progesterona vaginal micronizada poderia aumentar a taxa de nascidos vivos em mulheres com ameaça de aborto e com história de um ou mais abortos anteriores (risco relativo [RR]: 1,08, intervalo de confiança [IC] de 95%: 1,02-1,15). O benefício foi maior no subgrupo de mulheres com três ou mais perdas anteriores. Conclusão: Ainda restam dúvidas sobre o uso de "progesterona" nas pacientes com PGR inexplicada. Sua administração deve ser discutida individualmente com cada mulher, levando-se em conta especialmente a idade materna, o número de abortos prévios e a história de sangramento na gestação em curso, evitando-se tratamentos que trazem custos e não são isentos de efeitos colaterais.(AU)

Objective: To discuss the use of progestins in women with recurrent pregnancy loss (RPL) with no apparent cause, addressing types of progestins, and results of clinical trials, systematic reviews, and meta-analyses. Methods: This is a non-systematic review of articles published in the PubMed, Cochrane, SciELO electronic databases in the last five years, using the following descriptors: "progesterone", "dydrogesterone", "recurrent pregnancy loss", and "recurrent abortion". Results: Two large meta-analyses found a reduction in the rate of miscarriage, and an increase in the rate of live births with the use of synthetic progestin in patients with unexplained RPL, but this conclusion was challenged in a more recent meta-analysis. However, micronized vaginal progesterone could increase the rate of live births in women with a threatened miscarriage and a history of one or more previous miscarriages (RR: 1.08, 95% CI: 1.02-1.15). The benefit was greatest in the subgroup of women with three or more previous losses. Conclusion: There are still doubts about the use of "progesterone" in patients with unexplained RPL. Its administration should be discussed individually with each woman, taking into account especially the maternal age, number of previous abor tions, and history of bleeding during pregnancy, avoiding treatments that bring costs and are not free from side effects.(AU)

Endometrial Progesterone and Estrogen Receptors in Relation to Hormonal Levels in Women with Unexplained Recurrent Miscarriage / Receptores endometriais de progesterona e estrogênio em relação aos níveis hormonais em mulheres com aborto recorrente inexplicável

Abstract Objective Recurrent miscarriage has been linked to hormonal disturbance due to dysregulation of its receptors rather than to the availability of the hormone. We aimed to investigate endometrial expression of progesterone and estrogen receptors in relation to serum and endometrial hormonal levels in unexplained recurrent miscarriage. Methods The present case control study included 20 cases with unexplained recurrent miscarriage and 20 parous women as controls. Ovulation was confirmed using an ovulation kit and 10 to 12 days after detecting the urinary luteinizing hormone surge, all women were subjected to a blood sample and to an endometrial biopsy. Progesterone and estrogen levels were measured in serum and in endometrial tissue and receptor concentrations were in the endometrial sample. Results Women with recurrent miscarriage showed significantly lower concentration of receptors in both the cytoplasm and the nucleus of endometrial tissue compared with controls. The nuclear/cytoplasm ratio of progesterone receptor was significantly higher in cases compared with controls, implicating that recurrent miscarriage is probably linked to nongenomic activity of the hormone; this was also significant for estrogen receptor. Serum progesterone and estrogen hormonal levels were comparable between groups while both hormones were significantly reduced in the endometrium of recurrent miscarriage cases. Receptors significantly correlated with endometrial hormonal level but not to serum level. Conclusion Recurrent miscarriage might be linked to reduced endometrial progesterone and estrogen receptors and appears to be more related to nongenomic activity of progesterone. Endometrial receptors expression correlates to tissue hormonal level rather than to serum hormonal level.

Use of artificial intelligence to predict response to neoadjuvant chemotherapy in breast cancer

:Breast cancer is the object of thousands of studies worldwide. Nevertheless, few tools are available to corroborate prediction of response to neoadjuvant chemotherapy. Artificial intelligence is being researched for its potential utility in several fields of knowledge, including oncology. The development of a standardized Artificial intelligence-based predictive model for patients with breast cancer may help make clinical management more personalized and effective. We aimed to apply Artificial intelligence models to predict the response to neoadjuvant chemotherapy based solely on clinical and pathological data. Methods: Medical records of 130 patients treated with neoadjuvant chemotherapy were reviewed and divided into two groups: 90 samples to train the network and 40 samples to perform prospective testingand validate the results obtained by the Artificial intelligence method. Results: Using clinicopathologic data alone, the artificial neural network was able to correctly predict pathologic complete response in 83.3% of the cases. It also correctly predicted 95.6% of locoregional recurrence, as well as correctly determined whether patients were alive or dead at a given time point in 90% of the time. To date, no published research has used clinicopathologic data to predict the response to neoadjuvant chemotherapy in patients with breast cancer, thus highlighting the importance of the present study. Conclusions: Artificial neural network may become an interesting tool for predicting response to neoadjuvant chemotherapy, locoregional recurrence, systemic disease progression, and survival in patients with breast cancer (AU)

¿La progesterona natural micronizada previene el trabajo de parto pretérmino?: Revisión sistemática de literatura / Does Natural Micronized Progesterone Prevent Preterm Labor?: Systematic Literature Review / A progesterona natural micronizada previne o trabalho de parto prematuro?: Revisão sistemática da literatura

Introducción. La progesterona es una hormona que favorece el mantenimiento del embarazo, es la protagonista de la fisiopatología del trabajo de parto pretérmino. De esta manera, se propone realizar una revisión sistemática que permita demostrar la utilidad de la progesterona natural micronizada en la mitigación de los efectos deletéreos del trabajo de parto pretérmino. Metodología. Revisión sistemática en la que se utilizaron los términos "MeSH" y "No ­ MeSH". Se empleó el programa "Publish or Perish" y bases de datos como: Medline, PubMed, Embase, Clinical Key, Cochrane Library, Scopus y Google Scholar. Se incluyeron artículos de revisión, meta-análisis, artículos originales (publicaciones preliminares o completas), resúmenes de congresos, seminarios publicados, libros de texto, protocolos hospitalarios regionales y consensos nacionales, en donde cada autor evaluó individualmente cada artículo y aplicó la herramienta CASPE. Resultados. En la literatura no es posible encontrar pautas concisas internacionales sobre el uso de la progesterona micronizada frente a la amenaza de trabajo de parto pretérmino (TPP). En general, para la mitigación del trabajo de parto, según lo analizado por los autores, se recomienda usar progesterona natural micronizada en cápsulas de 100 a 400 mg/día vía oral o 100 a 200 mg cada 12 a 24 horas vía vaginal. Desde la semana 16 hasta la semana 36 de gestación por vía oral y desde la semana 24 a 34 de gestación por vía vaginal. Discusión. El uso de la progesterona micronizada ha demostrado mitigar complicaciones posteriores al trabajo de parto pretérmino, sin embargo, no hay consenso sobre la dosificación y las vías de administración. Sumado a lo anterior, los estudios analizados pueden contener sesgos, por lo que se deja a elección del clínico el uso este medicamento. Conclusiones. La progesterona natural micronizada podría ser empleada para mitigar el trabajo de parto pretérmino según los artículos analizados por los autores a lo largo de la revisión. Sin embargo, se necesitan más estudios para legitimar dicha hipótesis.

Introduction. Progesterone is a hormone that favors maintaining pregnancy. It is the protagonist of the physiopathology of preterm labor. In this sense, a systematic review is proposed to demonstrate the usefulness of natural micronized progesterone in mitigating the harmful effects of preterm labor. Methodology. A systematic review in which the terms "MeSH" and "No ­ MeSH" were used. The "Publish or Perish" program was used, as well as databases, such as: Medline, PubMed, Embase, Clinical Key, Cochrane Library, Scopus, and Google Scholar. Review and meta-analysis articles, original articles (preliminary or complete publications), congress summaries, published seminars, textbooks, regional hospital protocols and national consensuses were included, in which each author individually assessed each article and applied the CASPE tool. Results. It was not possible to find concise international guidelines on using micronized progesterone for the threat of preterm labor (PTL) in literature. According to what the authors analyzed, for the mitigation of labor it is generally recommended the use of natural micronized progesterone in 100 to 400 mg/day capsules orally or 100 to 200 mg every 12 to 24 hours through the vagina. From week 16 to week 36 of pregnancy orally and from week 24 to 34 through the vagina. Discussion. Using micronized progesterone has demonstrated mitigating complications subsequent to preterm labor. However, there is no consensus on dosage and routes of administration. Added to the above, the analyzed studies may contain biases, reason why using this medication is left to the physician's discretion. Conclusions. Natural micronized progesterone can be used to mitigate preterm labor according to the articles the authors analyzed throughout the review. However, more studies are needed to validate this hypothesis.

Introdução. A progesterona é um hormônio que favorece a manutenção da gravidez, é a protagonista da fisiopatologia do parto prematuro. Dessa forma, propõe-se a realização de uma revisão sistemática que permita demonstrar a utilidade da progesterona natural micronizada na mitigação dos efeitos deletérios do trabalho de parto prematuro. Metodologia. Revisão sistemática em que foram utilizados os termos "MeSH" e "Não­MeSH". Foram utilizados o programa "Publish or Perish" e bases de dados como: Medline, PubMed, Embase, Clinical Key, Cochrane Library, Scopus e Google Scholar. Foram incluídos artigos de revisão, meta-análises, artigos originais (publicações preliminares ou completas), resumos de congressos, seminários publicados, livros didáticos, protocolos hospitalares regionais e consensos nacionais, onde cada autor avaliou individualmente cada artigo e aplicou a ferramenta CASPE. Resultados. Não é possível encontrar na literatura diretrizes internacionais concisas sobre o uso de progesterona micronizada diante da ameaça de trabalho de parto prematuro (TPP). Em geral, para a mitigação do trabalho de parto, conforme analisado pelos autores, recomenda-se o uso de progesterona natural micronizada em cápsulas de 100 a 400mg/dia por via oral ou 100 a 200mg a cada 12 a 24 horas por via vaginal. Da 16ª à 36ª semana de gestação por via oral e da 24ª à 34ª semana de gestação por via vaginal. Discussão. O uso de progesterona micronizada demonstrou mitigar as complicações após o trabalho de parto prematuro, no entanto, não há consenso sobre a dosagem e as vias de administração. Além do exposto, os estudos analisados podem conter vieses, pelo que cabe ao médico escolher o uso deste medicamento. Conclusões. A progesterona natural micronizada poderia ser utilizada para mitigar o trabalho de parto prematuro de acordo com os artigos analisados pelos autores ao longo da revisão. No entanto, mais estudos são necessários para legitimar essa hipótese.

Oral dydrogesterone in frozen-thawed embryo transfer cycles

SUMMARY OBJECTIVE: The aim of this study was to compare the use of micronized vaginal progesterone and oral dydrogesterone in the endometrial preparation for frozen-thawed embryo transfer. METHODS: This was a randomized, controlled, open, two-armed clinical trial, with women undergoing frozen-thawed embryo transfer along with hormone replacement therapy for endometrial preparation, between September 2019 and February 2021. A total of 73 patients were randomly selected and orally administered 40 mg/day dydrogesterone (dydrogesterone group, n=36) or 800 mg/day micronized vaginal progesterone (micronized vaginal progesterone group, n=37), after endometrial preparation with transdermal estradiol. The main outcome was a viable ongoing pregnancy with 12 weeks of gestation as evaluated by ultrasound. RESULTS: The reproductive outcomes in frozen-thawed embryo transfer cycles were similar, with pregnancy rates in the dydrogesterone and micronized vaginal progesterone treatment groups being, respectively, 33.3 and 32.4% at 12 weeks pregnancy (confidence interval= -22.4-20.6, p=0.196). CONCLUSIONS: The use of oral dydrogesterone may be a more patient-friendly approach to endometrial preparation in frozen-thawed embryo transfer cycles, avoiding undesirable side effects and discomfort resulting from vaginal administration, while also providing similar reproductive results.

Association of raised serum progesterone level with ovulation trigger and histology of endometrium in stimulated cycles

Abstract This was a forthcoming study of those patients, who undergo in-vitro fertilization (IVF) and freeze-all embryo, who acquiesce for the study. The number of participated patients (n=350) in this study, underwent for IVF. The blood sample was collected from patients to evaluate the level of serum progesterone in vacuum vials on the day of ovulation trigger. After 36 hrs of ovulation trigger, ovum picked up was done. Quantitative methods were used to estimate the level of serum progesterone through the electrochemiluminescence immunoassay and correlation of serum progesterone with embryo transfer (ET) outcomes. Main outcome of this current study was to evaluate the value of mean serum progesterone level i.e.0.868± 0.712 ng/ml and 0.88±0.723 ng/ml was found in case of pregnancy positive and negative respectively, at p=0.216 value. In antagonist (n=40) and agonist (n=310) cases, it was 8(20%) and 37(11.94%) PL occurrence was noted at p=0.143 respectively. An overall value of the premature lutenization (PL) occurrences was 13.63% and 15.25% observed in both positive and negative cases of pregnancy at p=0.216 respectively. This study concluded that 12.66% of PL occurrences were recorded in the case of IVF. Study results proved, there were no significant effect of PL on pregnancy outcomes.

Establishment and comparison of two methods to produce a rat model of mammary gland hyperplasia with hyperprolactinemia

Abstract This study aimed to establish and compare models of mammary gland hyperplasia (MGH) with hyperprolactinemia (HPRL) using two different methods. The models provide information on the relationship between mammary gland hyperplasia and associated hormones. Model A was constructed using intramuscular injections of estradiol benzoate injection (EBI), followed by progesterone (P), and then metoclopramide dihydrochloride (MDI). Model B was designed by administering MDI, follow by EBI, and then P intramuscularly. Model B showed higher MGH progression compared with model A. Notably, increase in estradiol (E2) was negatively correlated with prolactin (PRL) secretion. However, PRL levels in model B were significantly higher compared with the levels in model A. Estrogen (ER), prolactin receptor (PRLR), and progesterone receptor (PR) mRNA and protein expression levels in model B rats were positively correlated with changes in the corresponding hormone levels. However, E2, P, and PRL levels in model A showed no direct relationship with levels of the mRNAs of related hormones and protein expression levels. Our results suggest that model B is an appropriate model of MGH with HPRL that can be used to perform further studies about the interactions of the E2, P, and PRL hormones in this disorder.

Retirada de corpo estranho (dispositivo impregnado com progesterona) da cavidade abdominal de novilha da raça Jersey ­ relato de caso / Removal of a foreign body (progesterone impregnated device) from the abdominal cavity of a Jersey heifer ­ a case report / Extracción de cuerpo extraño (dispositivo impregnado con progesterona) de la cavidad abdominal de novilla raza Jersey - reporte de caso

A inseminação artificial em tempo fixo (IATF) é uma biotécnica com inúmeras vantagens para a produção de bovinos. Para a realização da IATF, as fêmeas bovinas devem receber um protocolo farmacológico que induz a ovulação de forma sincronizada. Esse protocolo inicia com a inserção de um dispositivo impregnado com progesterona que deve permanecer no fundo vaginal da fêmea por tempo determinado. O presente relato tem por objetivo descrever a remoção de um implante impregnado com progesterona que foi encontrado na cavidade abdominal de uma novilha. Durante um atendimento reprodutivo de rotina em uma propriedade rural, uma novilha da raça Jersey, recém-adquirida, com histórico de ter sido submetida à IATF, foi avaliada para diagnóstico de gestação. No exame a novilha não estava gestante e apresentava um cisto folicular ovariano. A novilha foi submetida novamente à IATF em que foi inserido e removido um implante, com isso o cisto regrediu e ao inseminar a novilha não foi possível passar a cérvix com o aplicador. Vinte dias após a inseminação a novilha manifestou estro e ao ser avaliada para nova inseminação, foi identificado um implante solto na cavidade abdominal da novilha. Foi realizada uma laparotomia pelo flanco esquerdo e o implante foi removido. Após a recuperação da cirurgia a novilha foi inseminada e novamente e ficou gestante. Os protocolos de IATF devem ser realizados por profissionais capacitados para evitar problemas como a presente situação em que um implante foi encontrado na cavidade abdominal de uma novilha.(AU)

The fixed-time artificial insemination (FTAI) is a biotechnique with numerous advantages for cattle production. In order to perform the FTAI, the cows must receive a pharmacological protocol to induce ovulation in a synchronized way. This protocol begins with the insertion of a device impregnated with progesterone that must remain in the vaginal fundus of the cow for a specific period of time. This report aims at describing the removal of a progesterone impregnated implant that was found in the abdominal cavity of a heifer. During a routine reproductive service in a rural property, a recently acquired Jersey heifer, with history of having been submitted to FTAI, was evaluated for pregnancy diagnosis. At the exam, it was observed that the heifer was not pregnant and presented an ovarian follicular cyst. The heifer was then submitted to FTAI again, where an implant was inserted and removed. This made the cyst to recede, and upon subsequent insemination, the applicator was not able to pass the cervix. Twenty days after insemination, the heifer was in estrus and when it was evaluated for insemination, a loose implant was identified in the abdominal cavity of the heifer. A laparotomy was performed through the left flank and the implant was removed. After recovery from the surgery, the heifer was inseminated again and became pregnant. The FTAI protocols should only be carried out by trained professionals to avoid problems such as the one presented herein, where an implant was found in the abdominal cavity of a heifer.(AU)

La inseminación artificial a tiempo fijo (FTAI) es una biotécnica con numerosas ventajas para la producción de ganado. Para realizar FTAI, las hembras bovinas deben recibir un protocolo farmacológico que induzca la ovulación de forma sincronizada. Este protocolo comienza con la inserción de un dispositivo impregnado con progesterona que debe permanecer en el fondo vaginal de la hembra durante un tiempo específico. Este informe tiene como objetivo describir la extracción de un implante impregnado de progesterona que se encontró en la cavidad abdominal de una novilla. Durante la atención reproductiva de rutina en una propiedad rural, se evaluó el diagnóstico de preñez de una novilla de Jersey recién adquirida con antecedentes de someterse a FTAI. En el examen, la novilla no estaba embarazada y tenía un quiste folicular ovárico. La novilla fue nuevamente sometida a FTAI, en la cual se insertó y removió un implante, con esto el quiste retrocedió y al inseminar a la novilla no fue posible pasar el cérvix con el aplicador. Veinte días después de la inseminación, la vaquilla manifestó estro y cuando se evaluó para una nueva inseminación, se identificó un implante suelto en la cavidad abdominal de la vaquilla. Se realizó una laparotomía a través del flanco izquierdo y se extrajo el implante. Después de recuperarse de la cirugía, la novilla fue inseminada y nuevamente quedó embarazada. Los protocolos FTAI deben ser realizados por profesionales capacitados para evitar problemas como la situación actual donde se encontró un implante en la cavidad abdominal de una novilla.(AU)

Plasma metabolite changes in anestrous dairy cows with negative energy balance identified using 1H NMR technology / [Alterações do metabólito plasmático em vacas leiteiras com balanço energético negativo identificado usando a tecnologia 1H NMR]

The objective of the present study was to investigate the different plasma metabolites between anestrus and estrus postpartum dairy cows and to provide a theoretical basis for prevention of anestrus in dairy farm cows. In the experiment, one hundred and sixty-seven Holstein dairy cows were selected with similar age and parity. According to the concentration of ß-hydroxybutyric acid, non-esterified fatty acids and glucose in plasma during 14 to 21 days in milk, all dairy cows were determined as having a status of energy balance. According to the results of clinical symptom, rectal and B ultrasound examination at 60 to 90 days postpartum, these cows were divided into twenty estrus and twenty-four anestrus group, other dairy cows were removed. 1H nuclear magnetic resonance technology was utilized to detect the plasma metabolites changes and screen different plasma metabolites between anestrus and estrus cows. Ten different metabolites including alanine, glutamic acid, asparagine, creatine, choline, phosphocholine, glycerophosphocholine, low-density lipoprotein, and very-low-density lipoprotein were significantly decreased in anestrous cows compared with estrous cows. Metabolic pathway analyses indicated that differential metabolites were primarily involved in amino acid and glycerophospholipid metabolism. These metabolites and their enrichment pathways indicate that reduced steroid hormone synthesis precursors result in lower levels of estradiol and progesterone and cause anestrus in negative energy balance. These data provide a better understanding of the changes that may affect estrus of postpartum dairy cows at NEB status and lay the ground for further research.(AU)

O objetivo do presente estudo foi investigar os diferentes metabolitos do plasma entre o cio e o cio pós-parto de vacas leiteiras e fornecer uma base teórica para a prevenção do cio de vacas em fazendas de leite. No experimento, foram selecionadas 127 vacas leiteiras Holstein com idade e paridade similares. De acordo com a concentração de ß- ácido hidroxibutírico, ácidos graxos não esterificados e glicose no plasma entre 14 e 21 dias no leite, todas as vacas leiteiras foram determinadas em estado de equilíbrio energético. De acordo com os resultados dos sintomas clínicos, do exame de ultra-som retal e B aos 60 a 90 dias pós-parto, estas vacas foram divididas em vinte cios e vinte e quatro grupos de cio, outras vacas leiteiras foram removidas. A tecnologia de ressonância magnética nuclear 1H foi utilizada para detectar as alterações dos metabólitos plasmáticos e para triar diferentes metabólitos plasmáticos entre as vacas do cio e do cio. Dez diferentes metabólitos incluindo alanina, ácido glutâmico, asparagina, creatina, colina, fosfocholina, glicerofosfocolina, lipoproteína de baixa densidade e lipoproteína de muito baixa densidade foram significativamente diminuídos nas vacas antróficas em comparação com as vacas estro. As análises da via metabólica indicaram que os metabólitos diferenciais estavam principalmente envolvidos no metabolismo de aminoácidos e glicerofosfolipídios. Estes metabólitos e suas vias de enriquecimento indicam que a redução dos precursores da síntese de hormônios esteróides resulta em níveis mais baixos de estradiol e progesterona e causa anestros no balanço energético negativo. Estes dados fornecem uma melhor compreensão das mudanças que podem afetar o cio das vacas leiteiras pós-parto no estado de NEB e preparam o terreno para mais pesquisas.(AU)

Intravaginal progesterone device (1. 9g) and estradiol benzoate for follicular control in the mare during spring and summer / [Implante intravaginal de progesterona (1, 9g) e benzoato de estradiol no controle folicular de éguas durante a primavera e o verão]

The objective of this study was to evaluate follicular growth and ovulatory rates in mares treated with an intravaginal progesterone device (P4) during the 10-day period, associated with the use of estradiol benzoate (EB). The results were compared during the transition period (ET) in the spring and the breeding season in the summer (ER). The variables were submitted to ANOVA (Tukey's test), considering P<0.05. No ovulation occurred during the permanence of the P4 implant in both experimental periods. The ovulatory rate in the ER was 100% (n = 8) and in the ET 62.5% (n = 5; P = 0.0547). Significant differences were observed (<0.001), in both periods, comparing follicular growth rates during the permanence of P4 device (ER: 1.33 ± 0.89mm/d; ET: 1.00 ± 0.81mm/d) to the period without P4 (ER: 3.63 ± 1.33 mm/d; ET: 3.31 ± 1.66 mm/d). The present study demonstrated applicability and efficiency of a hormonal protocol using P4 intravaginal device and EB for follicular control in mares, both during ET and ER.

O objetivo deste trabalho foi avaliar a taxa de crescimento folicular e a taxa ovulatória em éguas tratadas com dispositivo intravaginal de progesterona (P4) durante o período de 10 dias, associado à utilização de benzoato de estradiol (BE). Os resultados foram comparados durante o período de transição (ET) da primavera com a época de reprodução no verão (ER). As variáveis foram submetidas à ANOVA (teste de Tukey), considerando-se P<0,05. Nenhuma ovulação ocorreu durante a permanência do dispositivo de P4 em ambos os períodos experimentais. A taxa ovulatória na ER foi de 100% (n = 8) e na ET, de 62,5% (n=5; P=0,0547). Diferença significativas (<0,001) foram observadas, em ambos os períodos experimentais, comparando as taxas de crescimento folicular durante a permanência da P4 (ER: 1,33 ± 0,89mm/d; ET: 1,00 ± 0,81mm/d) com o período sem P4 (ER: 3,63 ± 1,33mm/d; ET: 3,31 ± 1,66mm/d). O presente estudo demonstrou aplicabilidade e eficiência do protocolo hormonal utilizando dispositivo intravaginal de P4 e BE para controle folicular de éguas, tanto na ET quanto na ER.

Evaluation of progesterone receptor expression in low- and high-grade astrocytomas

SUMMARY OBJECTIVE: Gliomas are tumors originating from glial cells. Gliomas are the most common primary neoplasms of the central nervous system, with astrocytomas being the most prevalent glioma subtype. Progesterone regulates several reproductive processes, such as ovulation and sexual behavior, and influences neuronal excitability, learning, and the neoplastic proliferation of glial cells. Progesterone functions mainly by interacting with intracellular progesterone receptors to modify the expression of the genes involved in cell proliferation, angiogenesis, and epidermal growth factor production. As not many studies on the hormone receptors in glial tumors have been reported, the objective of this study was to evaluate the expression of these proteins in astrocytomas and to determine whether their expression levels vary according to the tumor grade. METHODS: This was a retrospective study using glial tumor paraffin blocks obtained from the São Marcos Hospital Pathology Department archives. Forty cases were divided equally into two groups, based on histological types and the World Health Organization criteria (low- and high-grade tumors). Progesterone receptor expression was analyzed by immunohistochemistry. The data were statistically analyzed using the Mann-Whitney U test and Spearman's correlation coefficient; results with p<0.05 were considered statistically significant. RESULTS: There were no statistically significant differences between the mean nuclear progesterone receptor expression of low-grade (0.1495) and high-grade (0.0937) astrocytomas (p=0.2). CONCLUSION: Progesterone receptors are present in both low- and high-grade gliomas; however, there is no significant difference in the levels of progesterone receptor expression between the tumor grades.

Use of cooled buffalo semen as a strategy to increase conception rates in fixed-time artificial insemination programs during unfavorable reproductive periods / [Uso de sêmen resfriado de búfalo como estratégia para aumentar as taxas de concepção em programas de inseminação artificial em tempo fixo, durante períodos reprodutivos desfavoráveis]

The objective of this study was to compare the reproductive efficiency of dairy buffaloes undergoing fixed-time artificial insemination (FTAI) protocols based on progesterone/estrogen (P4/E2) and eCG during unfavorable breeding season using cooled (CS) and frozen semen (FS). A total of 446 buffaloes (> 40 days postpartum) were randomly distributed into four blocks (years): B1-2014 (n = 143), B2-2015 (n = 34), B3-2016 (n = 90), and B4-2017 (n = 179). Each block was subdivided into two (AI with CS and FS using the same ejaculate of each bull). Thus, the block subdivision was as follows: B1 (CS = 71 and FS = 72); B2 (CS = 18 and FS = 16); B3 (CS = 47 and FS = 43); and B4 (CS = 90 and FS = 89). The ejaculates of eight Murrah bulls collected using an artificial vagina were divided into two aliquots: one aliquot was diluted in Botu-Bov® commercial extender and cooled (BB-CS), and the other was diluted in the same extender and frozen (BB-FS). BB-CS aliquots were cooled at 5 °C/24 h using a refrigerator. BB-FS group aliquots were also cooled, and after equilibrating at 5 °C for 4 h, were placed in a 21-L Styrofoam box, 5 cm above the surface of liquid nitrogen. In the afternoon (A) on D0 (2:00 p.m.) the animals received EB 2.0 mg IM (Estrogin®) and an ear implant (CRESTAR® 3.0 mg P4). At D9 (A), the implant was removed, and the animals received eCG 400 IU IM (Folligon® 5000) + Cloprostenol PGF2α 0.530 mg IM (Sincrocio®). At D10 (A), the animals received EB 1.0 mg IM (Estrogin®), and at D12 (8:00 a.m.), AI was performed. At D42, pregnancy was diagnosed via ultrasonography. Total CRs were 48.2% CS and 34.6% FS for years 2014 to 2017, with a significant difference of 13.7% (P<0.05). In conclusion, cooled semen resulted in higher CR than frozen semen in dairy buffaloes under the P4/E2 and eCG FTAI during the unfavorable reproductive season.(AU)

O objetivo deste estudo foi comparar a eficiência reprodutiva de búfalas leiteiras submetidas a protocolos de inseminação artificial em tempo fixo (IATF) à base de progesterona/estrogênio (P4/E2) e eCG, durante a estação reprodutiva desfavorável, usando-se sêmen resfriado (SR) e congelado (SC) Um total de 446 búfalas (> 40 dias após o parto) foi distribuído aleatoriamente em quatro blocos (anos): B1-2014 (n = 143), B2-2015 (n = 34), B3-2016 (n = 90) e B4-2017 (n = 179). Cada bloco foi subdividido em dois (IA com SR e SC utilizando-se a mesma ejaculação de cada touro). Assim, a subdivisão do bloco foi a seguinte: B1 (SR = 71 e SC = 72); B2 (SR = 18 e SC = 16); B3 (SR = 47 e SC = 43); e B4 (SR = 90 e SC = 89). Os ejaculados de oito touros Murrah coletados com vagina artificial foram divididos em duas alíquotas: uma alíquota diluída em diluente comercial Botu-Bov® e resfriada (BB-SR), e a outra diluída no mesmo diluente e congelada (BB-SC). As alíquotas de BB-SR foram resfriados a 5°C/24h usando-se um refrigerador. As alíquotas do grupo BB-SC também foram resfriadas e, após equilíbrio a 5°C por 4h, foram colocadas em uma caixa de isopor de 21L, 5 cm acima da superfície do nitrogênio líquido. À tarde (A), no D0 (14h), os animais receberam BE 2,0 mg IM (Estrogin®) e um implante auricular (Crestar® 3,0 mg P4). No D9 (A), o implante foi retirado e os animais receberam eCG 400 UI IM (Folligon® 5000) + cloprostenol PGF2α 0,530 mg IM (Sincrocio®). No D10 (A), os animais receberam BE 1,0mg IM (Estrogin®), e, no D12 (8h da manhã), foram realizadas as IAs. No D42, a gestação foi diagnosticada por ultrassonografia. As taxas de concepção (TC) totais foram 48,2% SR e 34,6% SC para os anos de 2014 a 2017, com uma diferença significativa de 13,7% (P<0,05). Em conclusão, o sêmen resfriado resultou em maior TC do que o sêmen congelado em bubalinos leiteiros sob P4/E2 e eCG FTAI durante a estação reprodutiva desfavorável.(AU)

Grado de desarrollo del folículo preovulatorio y su relación con el tamaño del cuerpo lúteo y la producción de progesterona en las razas Romosinuano (RS) y Brahman (Br) / Degree of development of the preovulatory follicle and its relationship with corpus luteum size and progesterone production in the Romosinuano (RS) and Brahman (Br) breeds

RESUMEN Para comparar en los folículos preovulatorios de hembras bovinas de las razas Brahman (Br) y Romosinuano (RS) el desarrollo de los diferentes componentes foliculares, como el tamaño del antro folicular, el grosor y el volumen ocupado por la capa de células de la granulosa (CG) y de la teca interna (TI), y su posible relación con el desarrollo del cuerpo lúteo (CL) y la producción de progesterona P4, se utilizaron 5 hembras de la raza RS y 5 de la raza Br. A estas se les realizó seguimiento ecográfico durante 2 ciclos estrales y se les efectuó muestreo de suero sanguíneo para determinar por Elisa los niveles de P4. En el tercer estro se les extirpó el ovario que contenía el folículo preovulatorio y se realizó un corte diametral sobre el estigma del folículo para seccionarlo en 2 partes iguales. En una de las partes se hicieron cortes histológicos y se determinó la morfometría folicular. La duración del ciclo estral en las hembras de la raza Br osciló entre 18 y 21 días, con promedio de 19,9 ± 1,6 días, y en las vacas RS entre 18 y 24 días, con un promedio 21,2 ± 1,69 días. La duración del estro fue de 13,9 ± 6,98 y 9,60 ± 4,72 h para las razas RS y Br, respectivamente. El intervalo estro-ovulación fue de 21,20 ± 5,07 h para los animales de la raza Br y de 24,40 ± 6,43 para los RS. No se registraron diferencias entre razas ni en el grosor (RS: 55,12 ± 6,46 μm vs. Br: 49,48 ± 17,07 μm), p > 0,05, tampoco en el volumen ocupado por la capa de CG (RS: 27,93 ± 6,11 mm1 vs. Br: 25,40 ± 13,85 mm3) de los folículos preovulatorios p < 0,05, en el grosor (RS: 122,50 ± 20,53 μm vs. Br: 129,61 ± 84,85 μm) o en el volumen (RS: 64,97 ± 19,71 mm1 vs. Br: 59,83 ± 25,67 mm3) de las células de la TI. El máximo desarrollo de los CL para la totalidad de las hembras se alcanzó el día 12,6 ± 4,05 (día 0 = estro), con un diámetro promedio de 22,92 ± 3,60 mm. Para las de la raza RS el diámetro máximo fue 23,06 ± 3,9 mm y se observó en promedio el día 14,88 ± 3,4. Para las de la raza Br fue el día 10,00 ± 3,16 con un promedio de 22,75 ± 3,16 mm. En ese día, la concentración media de P4 fue de 5,37 ± 1,38 ng/ml para la raza RS y 5,74 ± 0,89 ng/ml para la raza Br. No se presentaron diferencias significativas entre razas (p > 0,05). Se concluyó que no existen diferencias en los eventos fisiológicos estudiados entre las razas RS y Br. Los hallazgos del presente estudio, sin duda, pueden servir de base para futuros análisis en los bovinos residentes en el trópico.

ABSTRACT To compare in the preovulatory follicles of bovine females of the Brahman (Br) and Romosinuano (RS) breeds the development of the different follicular components, such as the size of the follicular antrum, the thickness and volume occupied by the granulosa (CG) and theca interna cells (TI) layers and their possible relationships with the development of the corpus luteum (CL) and progesterone (P4) production, 5 RS and 5 Br females were used; ultrasound follow-up was performed during 2 estrous cycles and blood serum sampling was carried out to determine progesterone (P4) levels by Elisa, at the third estrus, the ovary containing the preovulatory follicle was removed, and a diametral cut was made on the stigma of the follicle to divide it into 2 equal parts. Histological sections were made of one of the parts and follicular morphometry was determined. Duration of the estrous cycle in Br females ranged between 18 and 21 days, with an average of 19,9 ± 1,6 days and between 18 and 24 with an average of 21,2 ± 1,69 days for RS cows. Estrus duration was 13,9 ± 6,98 and 9,60 ± 4,72 h for RS and Br breeds, respectively. The estrus-ovulation interval was 21,20 ± 5,07 h for the Br breed animals and 24,40 ± 6,43 RS. There were no differences between breeds or in thickness (RS: 55,12 ± 6,46 μm vs. Br: 49,48 ± 17,07 μm) p > 0,05, nor in the volume occupied by the granulosa cells layer (RS: 27,93 ± 6,11 mm3 vs. Br: 25,40 ± 13,85 mm3) of pre-ovulatory follicles; neither in the thickness (RS: 122,50 ± 20,53 vs. Br: 129,61 ± 84,85 μm) nor in the volume (RS: 64,97 ± 19,71 mm3 vs. Br: 59,83 ± 25,67 mm3) of the internal theca cells; p < 0,05. The maximum CL development for all the females was observed on day 12,6 ± 4,05 (day 0 = estrus), with an average diameter of 22,92 ± 3,60 mm. For those of the RS breed the maximum diameter was observed on average on day 14,88 ± 3,4, with 23,06 ± 3,9 mm, while for those of the Br breed it was day 10,00 ± 3,16 with an average diameter of 22,75 ± 3,16 mm; at this time the mean progesterone concentration was 5,37 ± 1,38 ng/ml for the RS breed and 5,74 ± 0,89 ng/ml for the Br breed. There were no significant differences between breeds (p-value: 0,5561). It was concluded that there are no differences in the physiological events studied between the studied breeds. Present results, undoubtedly, might serve as basis to future studies in bovines in tropical zones.