scholarly journals Human oocytes and zygotes are ready for ultra-fast vitrification after 2 minutes of exposure to standard CPA solutions

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Miguel Gallardo ◽  
Jaime Saenz ◽  
Ramon Risco
Keyword(s):  
Clinical Practice ◽  
Solute Concentration ◽  
Short Exposure ◽  
Permeability Model ◽  
Human Oocytes ◽  
Glass Forming ◽  
Direct Exposure ◽  
Osmotic Behaviour ◽  
Two Parameter

Abstract Vitrification of human oocytes and embryos in different stages of development is a key element of daily clinical practice of in vitro fertilization treatments. Despite the cooling and warming of the cells is ultra-fast, the procedure as a whole is time consuming. Most of the duration is employed in a long (8–15 minutes), gradual or direct exposure to a non-vitrifying cryoprotectant solution, which is followed by a short exposure to a more concentrated vitrifying solution. A reduction in the duration of the protocols is desirable to improve the workflow in the IVF setting and reduce the time of exposure to suboptimal temperature and osmolarity, as well as potentially toxic cryoprotectants. In this work it is shown that this reduction is feasible. In silico (MatLab program using two-parameter permeability model) and in vitro observations of the oocytes’ osmotic behaviour indicate that the dehydration upon exposure to standard cryoprotectant solutions occurs very fast: the point of minimum volume of the shrink-swell curve is reached within 60 seconds. At that point, intracellular water ejection is complete, which coupled with the permeation of low molecular weight cryoprotectants results in similar intracellular and extracellular solute concentrations. This shows that prolonging the exposure to the cryoprotectant solutions does not improve the cytosolic glass forming tendency and could be avoided. To test this finding, human oocytes and zygotes that were donated for research were subjected to a shortened, dehydration-based protocol, consisting of two consecutive exposures of one-minute to two standard cryoprotectant solutions, containing ethylene glycol, dimethyl sulfoxide and sucrose. At the end of this two-minute dehydration protocol, the critical intracellular solute concentration necessary for successful vitrification was attained, confirmed by the post-warming survival and ability to resume cytokinesis of the cells. Further studies of the developmental competency of oocytes and embryos would be necessary to determine the suitability of this specific dehydration protocol for clinical practice, but based on our results, short times of exposure to increasingly hypertonic solutions could be a more time-efficient strategy to prepare human oocytes and embryos for vitrification.

Adverse Influence of Cigarette Smoking on the Endothelium

1993 ◽  
Vol 70 (04) ◽  
pp. 707-711 ◽  
Author(s):  
Andrew D Blann ◽  
Charles N McCollum
Keyword(s):  
Endothelial Cells ◽  
Von Willebrand Factor ◽  
Tobacco Smoke ◽  
Lipid Peroxides ◽  
Short Exposure ◽  
Acute Effects ◽  
Adverse Influence ◽  
Von Willebrand ◽  
Willebrand Factor

SummaryThe effect of smoking on the blood vessel intima was examined by comparing indices of endothelial activity in serum from smokers with that from non-smokers. Serum from smokers contained higher levels of von Willebrand factor (p <0.01), the smoking markers cotinine (p <0.02) and thiocyanate (p <0.01), and was more cytotoxic to endothelial cells in vitro (p <0.02) than serum from non-smokers. The acute effects of smoking two unfiltered medium tar cigarettes was to briefly increase von Willebrand factor (p <0.001) and cytotoxicity of serum to endothelial cells in vitro (p <0.005), but lipid peroxides or thiocyanate were not increased by this short exposure to tobacco smoke. Although there were correlations between von Willebrand factor and smokers consumption of cigarettes (r = 0.28, p <0.02), number of years smoking (r = 0.41, p <0.001) and cotinine (r = 0.45, p <0.01), the tissue culture of endothelial cells with physiological levels of thiocyanate or nicotine suggested that these two smoking markers were not cytotoxic. They are therefore unlikely to be directly responsible for increased von Willebrand factor in the serum of smokers. We suggest that smoking exerts a deleterious influence on the endothelium and that the mechanism is complex.

Follicular fluid and assisted reproductive technology programs outcomes (literature review)

GYNECOLOGY ◽  
2020 ◽  
Vol 21 (6) ◽  
pp. 36-40
Author(s):  
Anna G. Burduli ◽  
Natalia A. Kitsilovskaya ◽  
Yuliya V. Sukhova ◽  
Irina A. Vedikhina ◽  
Tatiana Y. Ivanets ◽  
...  
Keyword(s):  
Clinical Practice ◽  
Assisted Reproductive Technology ◽  
Follicular Fluid ◽  
Economic Cost ◽  
Reproductive Technology ◽  
Art Programs ◽  
Vitro Fertilization ◽  
Non Invasive ◽  
Established Fact

The review presents data on metabolites in the follicular fluid (FF) from the perspective of reproductive medicine and their use in order to predict outcomes of assisted reproductive technology (ART) programs. It considers various components of this biological medium (hormones, lipids, melatonin, etc.) with an assessment of their predictive value in prognosis of the effectiveness of in vitro fertilization (IVF) programs. The data on experimental directions in this field and the prospects for their use in clinical practice are presented. The article emphasizes that the growing clinical need and the unsolved problem of increasing the effectiveness of ART programs determine the need for further studies of the FF composition. Materials and methods. The review includes data related to this topic from foreign and Russian articles found in PubMed which were published in recent years. Results. Given the established fact of a direct effect of FF composition on growth and maturation of oocytes, and further, on the fertilization process, various FF metabolites are actively investigated as non-invasive markers of quality of oocytes/embryos. The article provides data on the experimental directions in this field and the prospects for their use in clinical practice. However, clinical studies of a relation between various FF metabolites levels and outcomes of IVF programs are contradictory. Conclusion. Owing large economic cost for treatment of infertility with IVF, there is need for expansion and intensification of studies to identify and use reliable predictors in prognosis of ART programs outcomes.

The end of the laboratory developed test as we know it? Recommendations from a national multidisciplinary taskforce of laboratory specialists on the interpretation of the IVDR and its complications

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Paul C. D. Bank ◽  
Leo H. J. Jacobs ◽  
Sjoerd A. A. van den Berg ◽  
Hanneke W. M. van Deutekom ◽  
Dörte Hamann ◽  
...  
Keyword(s):  
Clinical Practice ◽  
The Netherlands ◽  
Medical Devices ◽  
Task Force ◽  
Large Impact ◽  
Guidance Document ◽  
Scientific Societies ◽  
Clinical Laboratories ◽  
The Impact

AbstractThe in vitro diagnostic medical devices regulation (IVDR) will take effect in May 2022. This regulation has a large impact on both the manufacturers of in vitro diagnostic medical devices (IVD) and clinical laboratories. For clinical laboratories, the IVDR poses restrictions on the use of laboratory developed tests (LDTs). To provide a uniform interpretation of the IVDR for colleagues in clinical practice, the IVDR Task Force was created by the scientific societies of laboratory specialties in the Netherlands. A guidance document with explanations and interpretations of relevant passages of the IVDR was drafted to help laboratories prepare for the impact of this new legislation. Feedback from interested parties and stakeholders was collected and used to further improve the document. Here we would like to present our approach to our European colleagues and inform them about the impact of the IVDR and, importantly we would like to present potentially useful approaches to fulfill the requirements of the IVDR for LDTs.

scholarly journals Transient ICD malfunctions during oncologic radiotherapy: a multi-centre, randomized, in-vitro study

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
E Di Girolamo ◽  
M Appignani ◽  
N Furia ◽  
M Marini ◽  
P De Filippo ◽  
...  
Keyword(s):  
Real Time ◽  
Treatment Plan ◽  
Low Energy ◽  
In Vivo Dosimetry ◽  
Implantable Cardioverter Defibrillators ◽  
Shock Delivery ◽  
Transient Electromagnetic ◽  
Direct Exposure

Abstract Background Direct exposure of implantable cardioverter-defibrillators (ICDs) during radiotherapy is still considered potentially harmful, or even unsafe, by manufacturers and current recommendations. The effects of photon beams on ICDs are unpredictable, depending on multiple factors, and malfunctions may present during exposure. Purpose To evaluate transient ICD malfunctions by direct exposure to doses up to 10 Gy during low-energy RT, forty-three contemporary wireless-enabled ICDs, with at least 4 months to elective replacement indicator (ERI) were evaluated in a real-time in-vitro session in three different centres. Methods All ICDs had baseline interrogation. Single chamber devices were programmed to the VVI/40 mode and dual or triple chamber devices were programmed to the DDD/40 mode. Rate response function and antitachycardia therapies were disabled, with the ventricular tachycardia (VT)/ventricular fibrillation (VF) detection windows still active. A centring computed tomography was performed to build the corresponding treatment plan and the ICDs were blinded randomized to receive either 2-, 5- or 10-Gy exposure by a low photon-energy linear accelerator (6MV) in a homemade water phantom (600 MU/min). The effective dose received by the ICDs was randomly assessed by an in-vivo dosimetry. During radiotherapy, the ICDs were observed in a real-time session using manufacturer specific programmer, and device function (pacing, sensing, programmed parameters, arrhythmia detections) was recorder by the video camera in the bunker throughout the entire photon exposure. All ICDs had an interrogation session immediately after exposure. Results During radiotherapy course, almost all ICDs (93%) recorded major or minor transient electromagnetic interferences. On detail, sixteen ICDs (37.2%) reported atrial and/or ventricular oversensing, with base-rate-pacing inhibition and VT/VF detection. Twenty-four ICDs (55.8%) recorded non clinically relevant noise, and no detections were observed. Only three ICDs (7%) reported neither transient malfunction nor minor noise, withstanding direct radiation exposure. At immediate post-exposure interrogation, the ICDs that recorded major real-time malfunctions had VT/VF detections stored in the device memory. In none of the ICDs spontaneous changes in parameter settings were reported. Malfunctions occurred regardless of either 2-, 5- or 10-Gy photon beam exposure. Conclusions Transient electromagnetic interferences were observed in most of the contemporary ICDs during radiotherapy course, regardless of photon dose. To avoid potentially life-threatening ICD malfunctions such as pacing inhibition or inappropriate shock delivery, magnet application on the pocket site or ICD reprogramming to the asynchronous mode are still suggested in ICD patients ongoing even low energy radiotherapy exposure. Funding Acknowledgement Type of funding source: None

Chromosome and spindle configurations of human oocytes matured in vitro after cryopreservation at the germinal vesicle stage

1997 ◽  
Vol 68 (5) ◽  
pp. 920-926 ◽  
Author(s):  
Sung-Eun Park ◽  
Weon-Young Son ◽  
Sook-Hwan Lee ◽  
Kyung-Ah Lee ◽  
Jung-Jae Ko ◽  
...  
Keyword(s):  
Germinal Vesicle ◽  
Human Oocytes

Maturation and apoptosis of human oocytes in vitro are age-related

2000 ◽  
Vol 74 (6) ◽  
pp. 1137-1141 ◽  
Author(s):  
Ji Wu ◽  
Lizhu Zhang ◽  
Xiuyun Wang
Keyword(s):  
Human Oocytes ◽  
Age Related

Shortening the Application Time of Alcohol-Based Hand Rubs to 15 Seconds May Improve the Frequency of Hand Antisepsis Actions in a Neonatal Intensive Care Unit

2017 ◽  
Vol 38 (12) ◽  
pp. 1430-1434 ◽  
Author(s):  
Axel Kramer ◽  
Didier Pittet ◽  
Romana Klasinc ◽  
Stefan Krebs ◽  
Torsten Koburger ◽  
...  
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Clinical Practice ◽  
Neonatal Intensive Care Unit ◽  
Neonatal Intensive Care ◽  
Application Time ◽  
Improve Hand Hygiene ◽  
Independent Observer ◽  
Hand Antisepsis

BACKGROUNDFor alcohol-based hand rubs, the currently recommended application time of 30 seconds is longer than the actual time spent in clinical practice. We investigated whether a shorter application time of 15 seconds is microbiologically safe in neonatal intensive care and may positively influence compliance with the frequency of hand antisepsis actions.METHODSWe conducted in vitro experiments to determine the antimicrobial efficacy of hand rubs within 15 seconds, followed by clinical observations to assess the effect of a shortened hand antisepsis procedure under clinical conditions in a neonatal intensive care unit (NICU). An independent observer monitored the frequency of hand antisepsis actions during shifts.RESULTSAll tested hand rubs fulfilled the requirement of equal or even significantly higher efficacy within 15 seconds when compared to a reference alcohol propan-2-ol 60% (v/v) within 30 seconds. Microbiologically, reducing the application time to 15 seconds had a similar effect when compared to 30-second hand rubbing, but it resulted in significantly increased frequency of hand antisepsis actions (7.9±4.3 per hour vs 5.8±2.9 per hour; P=.05).CONCLUSIONTime pressure and workload are recognized barriers to compliance. Therefore, reducing the recommended time for hand antisepsis actions, using tested and well-evaluated hand rub formulations, may improve hand hygiene compliance in clinical practice.Infect Control Hosp Epidemiol 2017;38:1430–1434

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