scholarly journals Meiotic nondisjunction and sperm aneuploidy in humans

Reproduction ◽  
2018 ◽  
Author(s):  
Dimitrios Ioannou ◽  
Jenny Fortun ◽  
Helen Tempest
Keyword(s):  
Clinical Relevance ◽  
Clinical Implementation ◽  
Aneuploidy Screening ◽  
Preimplantation Genetic Testing ◽  
Specific Patient ◽  
Sperm Aneuploidy ◽  
Technological Developments ◽  
Patient Groups ◽  
Meiotic Nondisjunction

Infertility is relatively common affecting approximately 1-in-6 couples. Although the genetic basis of infertility is increasingly being uncovered, the contribution of male infertility often remains unexplained. The leading cause of pregnancy loss and cognitive impairment in humans is chromosome aneuploidy. Sperm aneuploidy is routinely evaluated by fluorescence in-situ hybridization. The majority of studies have reported similar findings, namely: 1) all men produce aneuploid sperm; 2) certain chromosomes are more prone to undergo chromosome nondisjunction; 3) infertile men typically have significantly higher levels of sperm aneuploidy compared to controls; and 4) the level of aneuploidy is often correlated with the severity of the infertility. Despite this, sperm aneuploidy screening is rarely evaluated in the infertility clinic. Within recent years, there appears to be renewed interest in the clinical relevance of sperm aneuploidy. We shall examine the gender differences in meiosis between the sexes, and explore why less emphasis is placed on the paternal contribution to aneuploidy. Increased sperm aneuploidy is often perceived to be modest and not clinically relevant, compared to the female contribution. However, even small increases in sperm aneuploidy may impact fertility and IVF cycle outcomes. Evidence demonstrating the clinical relevance of sperm aneuploidy will be discussed, as well as some of the challenges precluding widespread clinical implementation. Technological developments that may lead to widespread clinical implementation will be discussed. Recommendations will be suggested for specific patient groups that may benefit from sperm aneuploidy screening and whether preimplantation genetic testing for aneuploidy should be discussed with these patients.

Progress and Challenges in Laboratory-Based Diagnostic and Screening Approaches for Aneuploidy Detection during Pregnancy

2021 ◽  
pp. 247263032110217
Author(s):  
Lindsay Schneider ◽  
Anubhav Tripathi
Keyword(s):  
Sample Collection ◽  
Aneuploidy Screening ◽  
Preimplantation Genetic Testing ◽  
Cellular Division ◽  
Vitro Fertilization ◽  
Genetic Abnormalities ◽  
The Social ◽  
Diagnostic Technologies ◽  
Screening Approaches

Aneuploidy is caused by problems during cellular division and segregation errors during meiosis that lead to an abnormal number of chromosomes and initiate significant genetic abnormalities during pregnancy or the loss of a fetus due to miscarriage. Screening and diagnostic technologies have been developed to detect this genetic condition and provide parents with critical information about their unborn child. In this review, we highlight the complexities of aneuploidy as a disease as well as multiple technological advancements in testing that help to identify aneuploidy at various time points throughout pregnancy. We focus on aneuploidy diagnosis during preimplantation genetic testing that is performed during in vitro fertilization as well as prenatal screening and diagnosis during pregnancy. This review focuses on DNA-based analysis and laboratory techniques for aneuploidy detection through reviewing molecular- and engineering-based technical advancements. We also present key challenges in aneuploidy detection during pregnancy, including sample collection, mosaic embryos, economic factors, and the social implications of this testing. The goal of this review is to synthesize broad information about aneuploidy screening and diagnostic sample collection and analysis during pregnancy and discuss major challenges the field is still facing despite decades of advancements.

scholarly journals Non-medical risk factors associated with postponing elective surgery: a prospective observational study

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Julia Becker ◽  
Gerald Huschak ◽  
Hannes-Caspar Petzold ◽  
Volker Thieme ◽  
Sebastian Stehr ◽  
...  
Keyword(s):  
Elderly Patients ◽  
Low Socioeconomic Status ◽  
Elective Surgery ◽  
Nursing Home Residents ◽  
Hospital Staff ◽  
Data Management System ◽  
Electronic Patient Records ◽  
Specific Patient ◽  
Emergency Procedures ◽  
Patient Groups

Abstract Background Operation room (OR) planning is a complex process, especially in large hospitals with high rates of unplanned emergency procedures. Postponing elective surgery in order to provide capacity for emergency operations is inevitable at times. Elderly patients, residents of nursing homes, women, patients with low socioeconomic status and ethnic minorities are at risk for undertreatment in other contexts, as suggested by reports in the medical literature. We hypothesized that specific patient groups could be at higher risk for having their elective surgery rescheduled for non-medical reasons. Methods In this single center, prospective observational trial, we analysed 2519 patients undergoing elective surgery from October 2018 to May 2019. A 14-item questionnaire was handed out to illicit patient details. Additional characteristics were collected using electronic patient records. Information on the timely performance of the scheduled surgery was obtained using the OR’s patient data management system. 6.45% of all planned procedures analysed were postponed. Association of specific variables with postponement rates were analysed using the Mann–Whitney U test and Fisher's exact test/χ2-test. Results Significantly higher rates of postponing elective surgery were found in elderly patients. No significant differences in postponing rates were found for the variables gender, nationality (Germany, EU, non-EU), native language, professional medical background and level of education. Significantly lower rescheduling rates were found in patients with ties to hospital staff and in patients with a private health insurer. Conclusions Elderly patients, retirees and nursing home residents seem to be at higher risk for having their elective surgery rescheduled. However, owing to the study design, causality could not be proven. Our findings raise concern about possible undertreatment of these patient groups and provide data on short-term postponement of elective surgery. Trial registration DRKS00015836. Retrospectively registered.

scholarly journals Predictive Factors in Sacral Neuromodulation: A Systematic Review

2021 ◽  
pp. 1-21
Author(s):  
Ranjana Jairam ◽  
Jamie Drossaerts ◽  
Tom Marcelissen ◽  
Gommert van Koeveringe ◽  
Desiree Vrijens ◽  
...  
Keyword(s):  
Systematic Review ◽  
Predictive Factors ◽  
Sacral Neuromodulation ◽  
Level Of Evidence ◽  
Specific Patient ◽  
Detrusor Contractility ◽  
Affective Symptoms ◽  
Lower Success Rate ◽  
Patient Groups ◽  
Based Medicine

<b><i>Introduction:</i></b> Sacral neuromodulation (SNM) is an effective treatment in patients with overactive bladder syndrome or nonobstructive urinary retention when conservative treatment fails. Several factors that could impact outcome with SNM have been studied. This systematic review investigated these predictive factors and their relevance for clinical practice. <b><i>Methods:</i></b> Systematic review according to the PRISMA guidelines was conducted. This review is registered in the PROSPERO register (CRD42015016256). <b><i>Results:</i></b> Seventy-eight studies (of which 11 abstracts) were included. Females, younger patients, and a tined lead procedure tend to be predictive in successful SNM outcome. Factors that did not influence SNM outcome were prior back surgery, surgery for stress urinary incontinence, affective symptoms, and duration of complaints. Reduced detrusor contractility is associated with a lower success rate. The level of evidence of most studies (graded according to the Centre for Evidence-Based Medicine) was 3b. <b><i>Conclusion:</i></b> Even though this systematic review investigated predictive factors (gender, age, type of procedure, type of lead, and detrusor contractility), no general consensus on predictive factors could be made. Most studies are small, retrospective, and involve a heterogeneous population. Therefore, prospective research in larger specific patient groups remains necessary to find predictors of SNM outcome.

scholarly journals Advanced experimental approaches to marine water-column biogeochemical processes

2017 ◽  
Vol 75 (1) ◽  
pp. 30-42 ◽  
Author(s):  
Louis Legendre ◽  
Richard B Rivkin ◽  
Nianzhi Jiao
Keyword(s):  
Water Column ◽  
Numerical Models ◽  
Free Water ◽  
Sea Surface ◽  
Biogeochemical Processes ◽  
In Situ Experiments ◽  
Technological Developments ◽  
Approaches To Study ◽  
Experimental Approaches

Abstract This “Food for Thought” article examines the potential uses of several novel scientific and technological developments, which are currently available or being developed, to significantly advance or supplement existing experimental approaches to study water-column biogeochemical processes (WCB-processes). After examining the complementary roles of observation, experiments and numerical models to study WCB-processes, we focus on the main experimental approaches of free-water in situ experiments, and at-sea and on-land meso- and macrocosms. We identify some of the incompletely resolved aspects of marine WCB-processes, and explore advanced experimental approaches that could be used to reduce their uncertainties. We examine three such approaches: free-water experiments of lengthened duration using bioArgo floats and gliders, at-sea mesocosms deployed several 100s m below the sea-surface using new biogeochemical sensors, and 50 m-tall on-land macrocosms. These approaches could lead to significant progress in concepts related to marine WCB-processes.

scholarly journals 473 A Review of The Risk Stratification Models Used in The Management of Oncological Hepato-Pancreato-Biliary Surgical Patients

2021 ◽  
Vol 108 (Supplement_6) ◽  
Author(s):  
A Coombs ◽  
C Jordan ◽  
S Hussain ◽  
O Ghandour
Keyword(s):  
Decision Aids ◽  
Scoring Systems ◽  
Prognostic Scores ◽  
Clinical Implementation ◽  
Diverse Range ◽  
Ovid Medline ◽  
Current Trends ◽  
Patient Groups ◽  
Evidenced Based ◽  
User Friendly

Abstract Introduction Oncological scoring systems in surgery are used as evidence-based decision aids to best support management through assessing prognosis, effectiveness and recurrence. Currently, the use of scoring systems in the hepato-pancreato-biliary (HPB) subspecialty is limited as concerns over precision and applicability prevent widespread clinical implementation. The aim of the review is to discuss clinically useful oncological scoring systems for the surgical management of HPB patients. Method Primary articles of validated novel and established scoring systems were searched over a 25-year period using PubMed, Cochrane and Ovid Medline. Results This review discusses 9 clinically useful scoring systems in cancers of the liver (CLIP, BCLC, ALBI Grade, RETREAT, Fong et al.), pancreas (Genc et al., mGPS) and biliary tract (TMHSS, MEGNA). CLIP and BCLC are extensively validated prognostic tools, with BCLC clinically endorsed by guidelines. Conversely, patient and treatment stratification is limited in CLIP and BCLC respectively - ALBI works to improve patient stratification. RETREAT, Fong et al. and Genc et al. scores predict recurrence following surgery, however these scores require further validation in heterogenous patient groups. mGPS and MEGNA are simple prognostic scores, but also require further validation in varied patient cohorts. TMHSS is user-friendly, however is limited at discriminating treatment for the middle patient group. Conclusion A diverse range of HPB surgical scoring systems may facilitate evidenced-based treatment decisions and improve management. Future scoring systems need to be developed on heterogenous patient cohorts with improved stratification, with current trends towards implementing machine learning and genetics to improve outcome prediction.

scholarly journals Sensors and instruments for oceanic dissolved carbon measurements

2009 ◽  
Vol 6 (1) ◽  
pp. 491-524 ◽  
Author(s):  
U. Schuster ◽  
A. Hannides ◽  
L. Mintrop ◽  
A. Körtzinger
Keyword(s):  
Dissolved Inorganic Carbon ◽  
Analytical Techniques ◽  
Dissolved Carbon ◽  
Autonomous Mode ◽  
Technological Developments ◽  
Further Development ◽  
Temporal Coverage ◽  
Manual Mode

Abstract. Highly accurate and precise measurements of marine carbon components are required in the study of the marine carbon cycle, particularly when investigating the causes for its variability from seasonal to interannual timescales. This is especially true in the investigation of the consequences of anthropogenic influences. The analysis of any component requires elaborate instrumentation, most of which is currently used onboard ships, either in manual mode or autonomous mode. Technological developments result in more and more instruments that have long-term reliability so that they can be deployed on surface moorings and buoys, whilst the great technological and operational challenges mean that only few sensors have been developed that can be used for sub-surface in situ measurements on floats, robots, or gliders. There is a special need for autonomous instruments and sensors that are able to measure a combination of different components, in order to increase the spatial and temporal coverage of marine carbon data. This paper describes analytical techniques used for the detection of the marine dissolved carbon components, both inorganic and organic: the fugacity of CO2, total dissolved inorganic carbon, pH, alkalinity, and dissolved organic carbon. By pointing out advantages, disadvantages, and challenges of the techniques employed in the analysis of each component, we aim to aid non-carbon marine scientists, sensor developers and technologists, in the decision where to tackle the challenges of further development.

scholarly journals Subgroup analyses to determine cardiovascular risk associated with nonsteroidal antiinflammatory drugs and coxibs in specific patient groups

2008 ◽  
Vol 59 (8) ◽  
pp. 1097-1104 ◽  
Author(s):  
Daniel H. Solomon ◽  
Robert J. Glynn ◽  
Kenneth J. Rothman ◽  
Sebastian Schneeweiss ◽  
Soko Setoguchi ◽  
...  
Keyword(s):  
Cardiovascular Risk ◽  
Nonsteroidal Antiinflammatory Drugs ◽  
Antiinflammatory Drugs ◽  
Specific Patient ◽  
Subgroup Analyses ◽  
Patient Groups
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