Our findings illustrate the importance of PLCzeta during fertilization and suggest that mutant forms of PLCzeta may underlie certain types of human male infertility.
PLCzeta was variably detectable in three localities within the sperm head: the equatorial segment and acrosomal/post-acrosomal region. Variability in PLCzeta localization in sperm from fertile males may reflect differences in oocyte activation capabilities between individuals or within an ejaculate. This approach may help in investigating the possible links between PLCzeta and certain types of male infertility.
Recent studies suggest that egg activation in mammals is triggered by a sperm-specific phospholipase C, PLCzeta. In other vertebrate species such as medaka fish, chickens, and quail, PLCzeta is also expressed as a testis-specific mRNA. Functional studies suggest that PLCzeta plays a similar role as a trigger of egg activation in these species. Here, we report the identification of PLCzeta orthologues in pufferfish species Takifugu rubripes (Fugu) and Tetraodon nigroviridis (Tetraodon). Unexpectedly in these species PLCzeta is expressed not in the testis, but in ovary and brain. Injection of pufferfish PLCzeta copy ribonucleic acid (cRNA) into mouse eggs failed to trigger calcium oscillations, unlike medaka PLCzeta cRNA. Our findings provide the first evidence that PLCzeta may be expressed in the egg, rather than the sperm, in some vertebrate species, and that its mechanism of action and physiologic role at fertilization may differ in different vertebrate species.
Background: Caesarean sections (CS) are increasing worldwide. Financial incentives and related regulatory and legislative factors are important determinants of CS rates. This scoping review examines the evidence base of financial, regulatory and legislative interventions intended to reduce CS rates. Methods: We searched MEDLINE, EMBASE, CINAHL and two trials registers in June 2019. Both experimental and observational intervention studies were eligible for inclusion. Primary outcome measures were: CS, spontaneous vaginal and instrumental birth rates. We assessed quality of evidence using Grading of Recommendations, Assessment, Development and Evaluation (GRADE) method. Results: We identified 9057 articles and assessed 65 full-texts. We included 16 observational studies. Most of the studies were conducted in high-income countries. Three studies assessed payment methods for health workers: equalising physician fees for vaginal and caesarean delivery reduced CS rates in one study; however, little or no difference in CS rates was found in the remaining two studies. Nine studies assessed payment methods for health organisations: There was no difference in CS rates between diagnosis-related group (DRG) payment system compared to fee-forservice system in one study. However, DRG system was associated with lower odds for CS in another study. There was little or no difference in CS rates following implementation of global budget payment (GBP) system in two studies. Vaginal birth after caesarean section (VBAC) increased after implementation of a case-based payment system in one study. Caesarean section increased while VBAC rates decreased following implementation of a cap-based payment system in another study. Financial incentive for providers to promote vaginal delivery combined with free vaginal delivery policy was found to reduce CS rates in one study. Studied regulatory and legislative interventions (comprising legislatively imposed practice guidelines for physicians in one study and multi-faceted strategy which included policies to control CS on maternal request in another
Failed fertilization after intracytoplasmic sperm injection (ICSI) can be due to a reduced oocyte-activation capacity caused by reduced concentrations and abnormal localization of the oocyte-activation factor phospholipase C (PLC) zeta. Patients with this condition can be helped to conceive by artificial activation of oocytes after ICSI with calcium ionophore (assisted oocyte activation; AOA). However some concern still exists about this approach. Mouse models could help to identify potential oocyte-activation strategies and evaluate their safety. In this study, the fertilizing capacity of wobbler sperm cells was tested and the efficiency of AOA with two exposures to ionomycin to restore fertilization and embryo development was studied. The quality of the obtained blastocysts was assessed and embryo transfer was performed to evaluate post-implantation development. The presence of PLCzeta in the spermatozoa and testis of the wobbler mouse was evaluated by PLCzeta immunostaining and quantitative reverse-transcription polymerase chain reaction. Sperm cells from wobbler mice had reduced fertilizing capacity and abnormalities in PLCzeta localization, but not in its expression. Artificially activating the oocytes restored fertilization and embryo development. Therefore, the wobbler mouse can be a model for failed fertilization after ICSI to study PLCzeta dynamics and aid in optimization of the AOA method.
As health systems have become more expansive, strategic and operational planning processes have become more complex. Enterprise-wide strategic plans now address a broad set of considerations that have significant impact across the organization, particularly nursing and patient care programs. Synchronous implementation of organizational strategies can be very challenging. Organizational capacity is constantly challenged with competing agendas. To drive the successful implementation of organization-wide strategies and optimize success, Cleveland Clinic Foundation established a new role modeled after other industry sectors, the Associate Chief Nurse for Strategic Planning. This article describes the genesis and focus of this new, important role.
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