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1.
Reprod Biol ; 24(3): 100920, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38970979

RESUMO

At present, the success of non-surgical embryo recovery (NSER) and transfer (NSET) hinges upon the cervical passage of catheters, but penetration of the uterine cervix in ewes is problematic due to its anatomical structure (i.e., long and narrow cervical lumen with misaligned folds and rings). It is a major obstacle limiting the widespread application of NSER and NSET in sheep. While initial attempts to traverse the uterine cervix focused on adapting or re-designing insemination catheters, more recent studies demonstrated that cervical relaxation protocols were instrumental for transcervical penetration in the ewe. An application of such protocols more than tripled cervical penetration rates (currently at 90-95 %) in sheep of different breeds (e.g., Dorper, Lacaune, Santa Inês, crossbred, and indigenous Brazilian breeds) and ages/parity. There is now sufficient evidence to suggest that even repeatedly performed cervical passages do not adversely affect overall health and reproductive function of ewes. Despite these improvements, appropriate selection of donors and recipients remains one of the most important requirements for maintaining high success rates of NSER and NSET, respectively. Non-surgical ovine embryo recovery has gradually become a commercially viable method as even though the procedure still cannot be performed by untrained individuals, it is inexpensive, yields satisfactory results, and complies with current public expectations of animal welfare standards. This article reviews critical morphophysiological aspects of transcervical embryo flushing and transfer, and the prospect of both techniques to replace surgical methods for multiple ovulation and embryo transfer (MOET) programs in sheep. We have also discussed some potential pharmacological and technical developments in the field of non-invasive embryo recovery and deposition.


Assuntos
Colo do Útero , Transferência Embrionária , Animais , Feminino , Transferência Embrionária/métodos , Transferência Embrionária/veterinária , Ovinos/fisiologia , Colo do Útero/fisiologia , Colo do Útero/anatomia & histologia , Gravidez , Inseminação Artificial/veterinária
2.
Reproduction ; 167(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38271800

RESUMO

In brief: The cervix plays a crucial role not only in the maintenance of pregnancy but also during delivery, when it undergoes extensive changes. This study highlights the involvement of the endocannabinoidome in cervical remodeling, emphasizing its relevance in the shift from a nonpregnant to pregnant state and its potential contribution to preterm delivery in inflammatory contexts. Abstract: During pregnancy, the main role of the cervix is to isolate the fetus from outside pathogens and maintain the relatively closed system of uterine gestation. Conversely, toward the end of pregnancy, the cervix must be remodeled to increase flexibility and allow the delivery. This process is called cervical remodeling and dysregulation of the process plays a role in premature delivery. The endocannabinoidome plays an important role in several reproductive events; however, its function on cervical tissue throughout pregnancy is poorly understood. The goal of this study was to evaluate the presence and participation of the endocannabinoidome in lipopolysaccharide (LPS)-induced cervical changes. Therefore, we evaluated key components of the endocannabinoidome in cervical tissue from nonpregnant mice and pregnant mice with and without LPS treatment. Using mass spectrometric analysis, we found an increase in anandamide and 2-arachidonoylglycerol in the cervix of pregnant mice when compared to nonpregnant mice. We have also found a reduction in FAAH protein expression in these tissues. Furthermore, when treated with LPS, we observed a reduction in the cervical immunostaining with anti-CB1 and anti-CB2 antibodies. Likewise, using cervix explants from pregnant mice, we found that LPS significantly increased cervical metalloprotease activity and cyclooxygenase 2, which were subsequently modulated by cannabinoid receptor antagonists. Collectively, our findings suggest that an LPS-induced imbalance of cervix endocannabinoidome likely contributes to premature cervical remodeling, which is part of the key components that contribute to premature delivery.


Assuntos
Trabalho de Parto Prematuro , Nascimento Prematuro , Gravidez , Humanos , Feminino , Camundongos , Animais , Colo do Útero/fisiologia , Endocanabinoides/farmacologia , Lipopolissacarídeos/farmacologia , Útero/metabolismo , Trabalho de Parto Prematuro/metabolismo , Nascimento Prematuro/metabolismo
3.
Biomech Model Mechanobiol ; 20(3): 861-878, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33791911

RESUMO

The purpose of this study is to theoretically investigate the electro-magneto-biomechanics of the swimming of sperms through cervical canal in the female reproductive system. During sexual intercourse, millions of sperms migrate into the cervix in large groups, hence we can approximately model their movement activity by a swimming sheet through the electrically-conducting biofluid. The Eyring-Powell fluid model is considered as the base fluid to simulate male's semen with self-propulsive sperms. An external magnetic field is applied on the flow in transverse direction. The governing partial differential system of equations is analytically solved. Creeping flow regimen is employed throughout the channel due to self-propulsion of swimmers along with long wavelength approximation. Solutions for the stream function, velocity profile, and pressure gradient (above and below the swimming sheet) are obtained and plotted with the pertinent parameters. The prominent features of pumping characteristics are also investigated. Results indicate that the propulsive velocity is reduced with an increase in the electric field which is an important feature that can be used in controlling the transport of spermatozoa inside the cervical canal. Not only is the present analysis valid for living micro-organisms, but also valid for artificially designed electro-magnetic micro-swimmers which is further utilized in electro-magnetic therapy taking place in female's lubricous cervical canal filled with mucus.


Assuntos
Colo do Útero/fisiologia , Imãs , Movimento/fisiologia , Espermatozoides/fisiologia , Feminino , Humanos , Hidrodinâmica , Masculino , Modelos Biológicos , Muco/metabolismo , Pressão , Reologia
4.
Femina ; 49(7): 433-438, 2021.
Artigo em Português | LILACS | ID: biblio-1290593

RESUMO

A prematuridade é uma síndrome com múltiplos fatores de risco e cuja causa permanece desconhecida, mas, independentemente da etiologia, a parturição converge para uma via final comum de esvaecimento, dilatação e encurtamento do colo uterino. Do ponto de vista hormonal, o responsável por esse processo é a progesterona. A prevenção de quadros de prematuridade pode basear-se em tratamentos medicamentosos como a administração diária de comprimidos de progesterona; intervenções cirúrgicas para a contenção da cérvice uterina com fios inabsorvíveis mantidos até o termo, a cerclagem cervical; e o pessário cervical, dispositivo de silicone que envolve e inclina o colo uterino, evitando sua abertura. Para propor qualquer intervenção profilática ou terapêutica, a avaliação ultrassonográfica via transvaginal no segundo trimestre gestacional desempenha papel crucial. Apresentamos neste terceiro e último artigo da série sobre parto pré-termo espontâneo as intervenções terapêuticas e o rastreamento do colo uterino.(AU)


Preterm birth is a syndrome with multiple risk factors, with unknown etiology. Parturition converges to a final path with uterine cervix effacement, dilation and shortening and progesterone is the hormone responsible for this process. Preterm birth prevention relies on daily administration of progesterone pills; cerclage as a surgical intervention; or cervical pessary, a vaginal silicone device that enfolds and deflects the cervix, avoiding its opening. To propose any of these interventions it is crucial to evaluate the cervix during the second trimester by transvaginal ultrasound. Here, in the third and last article regarding preterm birth without membrane disruption, we present therapeutic interventions and ultrasound screening.(AU)


Assuntos
Humanos , Feminino , Gravidez , Recém-Nascido , Colo do Útero/fisiologia , Trabalho de Parto Prematuro/cirurgia , Trabalho de Parto Prematuro/prevenção & controle , Trabalho de Parto Prematuro/tratamento farmacológico , Pessários , Progesterona/uso terapêutico , Incompetência do Colo do Útero , Ultrassonografia Pré-Natal , Maturidade Cervical , Cerclagem Cervical , Medida do Comprimento Cervical
5.
JBRA Assist Reprod ; 24(1): 66-69, 2020 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-31693317

RESUMO

OBJECTIVE: To define the factors associated with clinical pregnancy after intrauterine insemination. METHODS: Retrospective study involving 633 infertility couples, which made up to 1053 cycles of intrauterine insemination. We analyzed the clinical pregnancy rate associated with different factors through the Chi-square test or Fisher's exact test. RESULTS: The clinical pregnancy rate was 8.2% per insemination cycle and 13.6% per treated couple. The factors with greater association to clinical pregnancy were to have more than two follicles, to perform the procedure without difficulty, to have 3 years or less of infertility, cervical factor as indication, use of gonadotropins and age less than 38 years. CONCLUSION: Intrauterine insemination requires to be accompanied by proper selection and couples' preparation.


Assuntos
Inseminação Artificial/estatística & dados numéricos , Gravidez/estatística & dados numéricos , Adulto , Fatores Etários , Colo do Útero/fisiologia , Feminino , Humanos , Infertilidade/terapia , Inseminação Artificial/métodos , Masculino , Estudos Retrospectivos
6.
Trop Anim Health Prod ; 51(5): 1179-1186, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30685834

RESUMO

This study aimed to evaluate the impact of subarachnoid anesthesia with ketamine during transcervical artificial insemination (TCAI) on the welfare of ewes and on subsequent pregnancy rates. Ninety Suffolk adult ewes were randomized into three treatment groups: control group (CG), which underwent the TCAI procedure as established by cervical traction (CG; n = 30) and two groups that received subarachnoid anesthesia with ketamine at a dose of either 0.75 mg/kg (KE0.75; n = 30) or 1.5 mg/kg (KE1.5; n = 30) 5 min before the cervical traction procedure. Intrauterine insemination was performed using frozen semen from three males previously analyzed and approved for fertility. The use of subarachnoid anesthesia decreased ewes' vocalizations (P = 0.0001) and abdominal contraction (P = 0.0150) during cervical manipulations. The CG had more groans and vocalizations at the moment of cervix clamping and applicator passage through the cervix (P = 0.001). The cervix traction was facilitated by anesthesia. For the control group, most of the cervical traction was done just up to the middle of the vagina (P = 0.0021). Pregnancy rates increased significantly with anesthesia (P = 0.04) as shown by the rates of 40.0%, 56.7%, and 66.7% for CG, KE1.5, and KE0.75, respectively. The CG showed behaviors associated with absolute immobility, which is suggestive of distress. In brief, the use of ketamine in subarachnoid anesthesia for transcervical artificial insemination in ewes facilitated cervical traction, increased the pregnancy rate, and improved animal welfare.


Assuntos
Anestesia/veterinária , Anestésicos Dissociativos/administração & dosagem , Bem-Estar do Animal , Inseminação Artificial , Ketamina/administração & dosagem , Taxa de Gravidez , Ovinos/fisiologia , Animais , Colo do Útero/fisiologia , Feminino , Inseminação Artificial/métodos , Gravidez , Distribuição Aleatória , Sêmen/fisiologia , Preservação do Sêmen/métodos , Espaço Subaracnóideo/fisiologia
7.
Reprod Domest Anim ; 54(1): 126-128, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30099771

RESUMO

This study evaluated the cervical transposition method as a tool to select ewes for embryo collection by transcervical route. Adult Santa Inês ewes (n = 50) received Day 0 protocol for superovulation treatments. The cervix transposition test was performed both at oestrus and at the embryo collection time. The latter was preceded by hormonal cervical dilation. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 85.7%, 66.6%, 85.7%, 66.6% and 80.0%, respectively. The kappa index yielded a moderate score (κ = 0.52). In conclusion, the high sensitivity and accuracy indicate that the cervical transposition test is a screening option to select ewes for embryo collection by transcervical route.


Assuntos
Colo do Útero/fisiologia , Dilatação/veterinária , Carneiro Doméstico , Coleta de Tecidos e Órgãos/veterinária , Animais , Dilatação/instrumentação , Dilatação/métodos , Embrião de Mamíferos , Estro , Feminino , Sensibilidade e Especificidade , Superovulação , Coleta de Tecidos e Órgãos/métodos
9.
Rev Bras Ginecol Obstet ; 38(12): 585-588, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27992933

RESUMO

Objective Analyzing if the sonographic evaluation of the cervix (cervical shortening) is a prognostic marker for vaginal delivery. Methods Women who underwent labor induction by using dinoprostone were enrolled. Before the induction and three hours after it, the cervical length was measured by ultrasonography to obtain the cervical shortening. The cervical shortening was introduced in logistic regression models among independent variables and for calculating receiver operating characteristic (ROC) curves. Results Each centimeter in the cervical shortening increases the odds of vaginal delivery in 24.4% within 6 hours; in 16.1% within 24 hours; and in 10.5% within 48 hours. The best predictions for vaginal delivery are achieved for births within 6 and 24 hours, while the cervical shortening poorly predicts vaginal delivery within 48 hours. Conclusion The greater the cervical shortening 3 hours after labor induction, the higher the likelihood of vaginal delivery within 6, 24 and 48 hours.


Assuntos
Colo do Útero/diagnóstico por imagem , Trabalho de Parto Induzido , Parto/fisiologia , Colo do Útero/fisiologia , Feminino , Humanos , Gravidez , Curva ROC , Fatores de Tempo , Ultrassonografia
10.
Rev. bras. ginecol. obstet ; 38(12): 585-588, Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-843890

RESUMO

ABSTRACT Objective: Analyzing if the sonographic evaluation of the cervix (cervical shortening) is a prognostic marker for vaginal delivery. Methods: Women who underwent labor induction by using dinoprostone were enrolled. Before the induction and three hours after it, the cervical length was measured by ultrasonography to obtain the cervical shortening. The cervical shortening was introduced in logistic regression models among independent variables and for calculating receiver operating characteristic (ROC) curves. Results: Each centimeter in the cervical shortening increases the odds of vaginal delivery in 24.4% within 6 hours; in 16.1% within 24 hours; and in 10.5% within 48 hours. The best predictions for vaginal delivery are achieved for births within 6 and 24 hours, while the cervical shortening poorly predicts vaginal delivery within 48 hours. Conclusion: The greater the cervical shortening 3 hours after labor induction, the higher the likelihood of vaginal delivery within 6, 24 and 48 hours.


RESUMO Objetivo: Analisar se a avaliação ultrassonográfica do colo do útero (encurtamento) é um marcador prognóstico para parto normal. Métodos: Consideramos mulheres com trabalho de parto induzido usando dinoprostona. Antes da indução e três horas após, a extensão cervical foi medida por ultrassonografia para obter o encurtamento do colo do útero. O encurtamento do colo do útero foi aplicado em modelos de regressão dentre variáveis independentes. Curvas de Característica de Operação do Receptor foram calculadas. Resultados: Cada centímetro no encurtamento do colo do útero aumenta as chances de parto normal para 24,4% dentro de 6 horas; 16,1% dentro de 24 horas; e 10,5% dentro de 48 horas. Os melhores preditores de parto normal são alcançados para partos dentre 6 e 24 horas, enquanto o encurtamento prevê mal o parto normal dentro de 48 horas.


Assuntos
Humanos , Feminino , Gravidez , Colo do Útero/diagnóstico por imagem , Trabalho de Parto Induzido , Parto/fisiologia , Colo do Útero/fisiologia , Curva ROC , Fatores de Tempo , Ultrassonografia
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