6 research outputs found

    Molecular and Cellular Mechanisms of Sperm-Oocyte Interactions Opinions Relative to in Vitro Fertilization (IVF)

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    One of the biggest prerequisites for pregnancy is the fertilization step, where a human haploid spermatozoon interacts and penetrates one haploid oocyte in order to produce the diploid zygote. Although fertilization is defined by the presence of two pronuclei and the extraction of the second polar body the process itself requires preparation of both gametes for fertilization to take place at a specific time. These preparations include a number of consecutive biochemical and molecular events with the help of specific molecules and with the consequential interaction between the two gametes. These events take place at three different levels and in a precise order, where the moving spermatozoon penetrates (a) the outer vestments of the oocyte, known as the cumulus cell layer; (b) the zona pellucida (ZP); where exocytosis of the acrosome contents take place and (c) direct interaction of the spermatozoon with the plasma membrane of the oocyte, which involves a firm adhesion of the head of the spermatozoon with the oocyte plasma membrane that culminates with the fusion of both sperm and oocyte membranes (Part I). After the above interactions, a cascade of molecular signal transductions is initiated which results in oocyte activation. Soon after the entry of the first spermatozoon into the oocyte and oocyte activation, the oocyte's coat (the ZP) and the oocyte's plasma membrane seem to change quickly in order to initiate a fast block to a second spermatozoon (Part II). Sometimes, two spermatozoa fuse with one oocyte, an incidence of 1%-2%, resulting in polyploid fetuses that account for up to 10%-20% of spontaneously aborted human conceptuses. The present review aims to focus on the first part of the human sperm and oocyte interactions, emphasizing the latest molecular and cellular mechanisms controlling this process

    Efficacy and Survival of Systemic Psoriasis Treatments: An Analysis of the Swiss Registry SDNTT.

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    BACKGROUND The Swiss psoriasis registry SDNTT (Swiss Dermatology Network for Targeted Therapies) records the long-term safety and effectiveness of systemic treatment regimens for psoriasis. PATIENTS AND METHODS Patients with moderate to severe psoriasis are included in the SDNTT when treatment with a conventional systemic agent or biologic is initiated that was not previously used by the respective patient. Patients are followed over a 5-year period. Clinical data are obtained every 3-6 months using standardized case report forms. Here, baseline data and follow-up data for 1 year of patients included from October 2011 until December 2014 were analyzed. RESULTS Within 39 months, 323 patients from 7 tertiary dermatology centers in Switzerland were recruited in the SDNTT; 165 patients received biologics and 158 conventional systemic therapies. Patients treated with biologics had a significantly higher severity (PASI 11.3 vs. 9.2, BSA 15.6 vs.11.9, psoriatic arthritis 36.4 vs. 10.8%; p ≤ 0.005, p ≤ 0.013, p ≤ 0.001) and a longer duration of illness (19.2 vs. 14.4 years, p ≤ 0.003) compared to patients starting a conventional systemic treatment. PASI reduction was satisfying in both treatment groups, with 60.6% of patients treated with biologics achieving PASI75 after 1 year compared to 54.2% of patients receiving conventional systemic drugs (nonsignificant). On average, the drug survival in patients receiving a biologic therapy was significantly longer than those receiving conventional systemic treatments (30.5 vs. 19.2 months, p ≤ 0.001). CONCLUSIONS In the real-world setting of a prospective national therapy registry, the application of current therapeutic guidelines for patients with moderate to severe psoriasis resulted in a PASI reduction of approximately 70% within the first year of treatment, but current therapeutic targets of PASI75 and PASI90 were reached in only 58 and 36% of patients, respectively, at 1 year, highlighting a gap in efficacy between selective clinical trials and the real-world setting
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