scholarly journals The micropyle: a sperm guidance system in teleost fertilization

Development ◽  
1990 ◽  
Vol 109 (2) ◽  
pp. 495-500 ◽  
Author(s):  
D. Amanze ◽  
A. Iyengar
Keyword(s):  
Time Lapse ◽  
Guidance System ◽  
Vitro Fertilization ◽  
Video Microscope ◽  
Computer Aided Analysis ◽  
Sperm Entry ◽  
Fertilization Experiments ◽  
Time Lapse Video

The micropylar region of the Rosy barb, Barbus conchonius, egg consists of 7–10 grooves and ridges, which drain directly into a funnel-shaped vestibule, the only point on the chorion through which sperm-egg contact is achieved during fertilization. Results of time-lapse video microscope study and computer-aided analysis of sperm motility pattern in the micropylar region showed that the fertilizing sperm, usually the first to enter the micropylar region, always travelled preferentially along the grooves into the micropylar pit. Subsequently, 86% of sperm arriving the micropylar region within 30 s travelled preferentially along the grooves into the immediate vicinity of the micropylar pit. The sperm guidance role of the micropylar region was calculated to enhance chances of egg penetration/fertilization by as much as 99.7% once sperm were within the micropylar region, possibly in response to some form of chemo-attractant(s) from the egg. Sperm agglutination post-fertilization was also found to occur preferentially along the grooves. Results of our in vitro fertilization experiments showed association between point of sperm entry and blastodisc formation: the blastodisc formed directly beneath the micropyle in all undisturbed eggs.

Activation of bovine oocytes by protein synthesis inhibitors: new findings on the role of MPF/MAPKs†

2021 ◽  
Author(s):  
Cecilia Valencia ◽  
Felipe Alonso Pérez ◽  
Carola Matus ◽  
Ricardo Felmer ◽  
María Elena Arias
Keyword(s):  
Protein Synthesis ◽  
Kinase Activity ◽  
Cyclin B1 ◽  
Protein Synthesis Inhibitors ◽  
Vitro Fertilization ◽  
New Findings ◽  
Bovine Oocytes ◽  
Dependent Pathway

Abstract The present study evaluated the mechanism by which protein synthesis inhibitors activate bovine oocytes. The aim was to analyze the dynamics of MPF and MAPKs. MII oocytes were activated with ionomycin (Io), ionomycin+anisomycin (ANY) and ionomycin+cycloheximide (CHX) and by in vitro fertilization (IVF). The expression of cyclin B1, p-CDK1, p-ERK1/2, p-JNK, and p-P38 were evaluated by immunodetection and the kinase activity of ERK1/2 was measured by enzyme assay. Evaluations at 1, 4, and 15 hours postactivation (hpa) showed that the expression of cyclin B1 was not modified by the treatments. ANY inactivated MPF by p-CDK1Thr14-Tyr15 at 4 hpa (P < 0.05), CHX increased pre-MPF (p-CDK1Thr161 and p-CDK1Thr14-Tyr15) at 1 hpa and IVF increased p-CDK1Thr14-Tyr15 at 17 hours postfertilization (hpf) (P < 0.05). ANY and CHX reduced the levels of p-ERK1/2 at 4 hpa (P < 0.05) and its activity at 4 and 1 hpa, respectively (P < 0.05). Meanwhile, IVF increased p-ERK1/2 at 6 hpf (P < 0.05); however, its kinase activity decreased at 6 hpf (P < 0.05). p-JNK in ANY, CHX, and IVF oocytes decreased at 4 hpa (P < 0.05). p-P38 was only observed at 1 hpa, with no differences between treatments. In conclusion, activation of bovine oocytes by ANY, CHX, and IVF inactivates MPF by CDK1-dependent specific phosphorylation without cyclin B1 degradation. ANY or CHX promoted this inactivation, which seemed to be more delayed in the physiological activation (IVF). Both inhibitors modulated MPF activity via an ERK1/2-independent pathway, whereas IVF activated the bovine oocytes via an ERK1/2-dependent pathway. Finally, ANY does not activate the JNK and P38 kinase pathways.

542 Objective Sleep Duration, Sleep Timing and Completion of In Vitro Fertilization Cycles; a Prospective Cohort Study

SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A214-A214
Author(s):  
Chawanont Pimolsri ◽  
Xiru Lyu ◽  
Cathy Goldstein ◽  
Chelsea Fortin ◽  
Sunni Mumford ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Sleep Duration ◽  
Medical Center ◽  
Working Women ◽  
Vitro Fertilization ◽  
Circadian Misalignment ◽  
Logistic Regression Models ◽  
Sleep Timing

Abstract Introduction Sleep duration and circadian misalignment have been linked to fertility and fecundability. However, sleep in women undergoing IVF has rarely been examined. This study investigated the role of sleep duration and timing with completion of an IVF cycle. Methods Prospective study of women undergoing IVF at a tertiary medical center between 2015 and 2017. Sleep was assessed by wrist-worn actigraphy 1–2 weeks prior to the initiation of their IVF cycle. Reproductive profile, IVF cycle details, demographic and health information were obtained from medical charts. Sleep duration, midpoint and bedtime were examined in relation to IVF cycle completion using logistic regression models, adjusted for age and anti-Müllerian hormone levels. A sub-analysis excluded women who worked non-day shifts to control for circadian misalignment. Results A total of 48 women were studied. Median age was 33y (range 25–42), with 29% of women older than 35 years. Ten women had an IVF cycle cancellation prior to embryo transfer. These women had shorter sleep duration, more nocturnal awakenings, lower sleep efficiency, and later sleep timing in comparison to those who completed their cycle. Twenty-minute increases in sleep duration were associated with lower odds of an uncompleted IVF cycle (OR = 0.88; 95% CI 0.78, 1.00). Women with later sleep midpoints and later bedtime had higher odds of an uncompleted cycle relative to those with earlier midpoints and earlier bedtime; OR=1.24; 95% CI 1.09, 1.40 and OR=1.33; 95% CI 1.17, 1.53 respectively, per 20-minute increments. These results were independent of age, levels of anti-Müllerian hormone, or sleep duration, and remained unchanged after exclusion of shift-working women. Conclusion This study demonstrated the influence of sleep duration and sleep timing on the odds of an uncompleted IVF cycle prior to embryo transfer. Sleep is a modifiable behavior that may contribute to IVF cycle success. Support (if any):

scholarly journals Novel Insights on the Role of Nitric Oxide in the Ovary: A Review of the Literature

2021 ◽  
Vol 18 (3) ◽  
pp. 980
Author(s):  
Maria Cristina Budani ◽  
Gian Mario Tiboni
Keyword(s):  
Nitric Oxide ◽  
In Vivo Studies ◽  
Published Data ◽  
Vitro Fertilization ◽  
Peripheral Neurons ◽  
Relevant Role ◽  
Oocyte Meiotic Maturation

Nitric oxide (NO) is formed during the oxidation of L-arginine to L-citrulline by the action of multiple isoenzymes of NO synthase (NOS): neuronal NOS (nNOS), endotelial NOS (eNOS), and inducible NOS (iNOS). NO plays a relevant role in the vascular endothelium, in central and peripheral neurons, and in immunity and inflammatory systems. In addition, several authors showed a consistent contribution of NO to different aspects of the reproductive physiology. The aim of the present review is to analyse the published data on the role of NO within the ovary. It has been demonstrated that the multiple isoenzymes of NOS are expressed and localized in the ovary of different species. More to the point, a consistent role was ascribed to NO in the processes of steroidogenesis, folliculogenesis, and oocyte meiotic maturation in in vitro and in vivo studies using animal models. Unfortunately, there are few nitric oxide data for humans; there are preliminary data on the implication of nitric oxide for oocyte/embryo quality and in-vitro fertilization/embryo transfer (IVF/ET) parameters. NO plays a remarkable role in the ovary, but more investigation is needed, in particular in the context of human ovarian physiology.

The scattered puzzle effect: implantation disorders in chronic endometritis

GYNECOLOGY ◽  
2020 ◽  
Vol 22 (6) ◽  
pp. 93-100
Author(s):  
Victor E. Radzinsky ◽  
Mekan R. Orazov ◽  
Liliia R. Toktar ◽  
Liudmila M. Mihaleva ◽  
Pavel A. Semenov ◽  
...  
Keyword(s):  
Uterine Cavity ◽  
Special Role ◽  
Inadequate Response ◽  
Chronic Endometritis ◽  
Vitro Fertilization ◽  
Endometrial Cells ◽  
Adverse Pregnancy ◽  
Relationship Of

Chronic endometritis (CE) is defined as a state of inflammation localized in the endometrium, accompanied by edema, dissociated maturation of epithelial cells and fibroblasts, increased stromal density and the presence of plasma cell infiltrate in it. The connection between chronic inflammation in the endometrium and infertility deserves special attention. Inadequate response of immunocompetent endometrial cells, including impaired synthesis of proinflammatory cytokines, dysreceptiveness, disorders of proliferation and differentiation processes are the main links in the formation of infertility in patients with CE. Despite the fact that the presence of a normocenosis of the uterine cavity today is not in doubt this is a physiological norm, persistent bacterial infection of the endometrium is still called the main etiopathogenetic factor of CE and, therefore, the main point of application of therapeutic agents. Nevertheless, a number of works have emphasized the special role of not bacterial, but viral etiology of endometritis, especially in the context of infertility developing against this background. It seems that the role of viral endometrial infection in adverse pregnancy outcomes and in vitro fertilization programs is underestimated. Further research is needed to clarify the relationship of viral infection as a trigger of implantation failure in infertile women with CE.

scholarly journals Aromatase P450 activity in the natural menstrual cycle and during controlled ovarian stimulation

2017 ◽  
Vol 66 (5) ◽  
pp. 46-55 ◽  
Author(s):  
Pavel P. Yakovlev
Keyword(s):  
Reproductive System ◽  
Oocyte Quality ◽  
Aromatase Activity ◽  
Female Reproductive System ◽  
Vitro Fertilization ◽  
P450 Enzyme ◽  
Follicular Response ◽  
P450 Activity

The Aim of the study was to assess modern considerations about the role of aromatase P450 enzyme in female reproductive system and the effect of its activity on the protocols of in vitro fertilization (IVF). Materials: foreign and Russian literature data from 1978 to 2016. Methods:review and synthesis of publications has been performed. Conclusions: Ovarian aromatase is the key steroidogenesis enzyme of the female reproductive system. Its activity depends on many factors, both of intraovarian and extragonadal origin. The ovarian follicular response and oocyte quality in IVF may depend on aromatase activity.

scholarly journals IN VITRO FERTILITY TEST OF HUMAN SPERMATOZOA MEMBRANE PROTEIN FERTILIN BETA ANTIBODY IN MICE (Mus musculus Balb/c) AS IMMUNOCONTRACEPTIVE CANDIDATE

2017 ◽  
Vol 52 (3) ◽  
pp. 209
Author(s):  
Reny I’tishom ◽  
Doddy M Soebadi ◽  
Aucky Hinting ◽  
Hamdani Lunardhi ◽  
Rina Yudiwati
Keyword(s):  
In Vitro Fertilization ◽  
Membrane Protein ◽  
Mus Musculus ◽  
Human Spermatozoa ◽  
Control Group ◽  
Reproductive Process ◽  
Vitro Fertilization ◽  
Antibody Induction

One of the materials as potential candidates immunocontraception material is spermatozoa. Fertilin beta is spermatozoa membrane protein and is found only in mature spermatozoa and ejaculate, which serves as an adhesion molecule. Spermatozoa membrane protein that is used as an ingredient immunocontraception candidate, must have specific criteria that the specificity of spermatozoa, the role of antigen in the fertilization process, which includes the formation of immunogenicity sufficient antibody response has the potential to block fertilization. Antibodies against spermatozoa affect the stages before fertilization of the reproductive process and can hinder the development of the embryo after fertilization. Until now very little research data spermatozoa membrane protein as an ingredient immunocontraception are up to the test of experimental animals. The research objective is to prove the role of the resulting antibody induction of antibodies fertilin beta protein in the membrane of human spermatozoa induce agglutination and reduce motility thus reducing the number of in vitro fertilization. Research conducted at the IVF Laboratory, Department of Biology of Medicine, Faculty of Medicine, University of Airlangga. This research includes: Test the potential of antibody protein beta fertilin membrane of human spermatozoa and inhibit the role of antibodies in vitro fertilization in mice (Mus musculus Balb/c). In vitro studies have resulted in fertilization figure of 25% is smaller than the number that is equal to control fertilization of 58.7%, whereas previously the spermatozoa were incubated first with a beta membrane protein antibody fertilin human spermatozoa. While the percentage of inhibition of sperm to fertilize an oocyte by 33.75%. Potential imunokontraseptif considered effective if it decreased significantly (P <0.05) than the numbers fertilization in the treatment group compared with the control group. This shows fertilin beta membrane protein antibody has the ability to inhibit human spermatozoa to fertilize oocytes that reduce the number of fertilization.

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