Kristian Leisegang

Kristian Leisegang
University of the Western Cape | uwc · School of Natural Medicine

PhD (Medical BioScience)

About

58
Publications
19,674
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
877
Citations
Introduction
Kristian currently research is focused on reproductive medicine, andrology, in the context of lifestyle exposures and risk factors such as obesity and metabolic syndrome. this includes supervision of post-graduate students and local and international collaborative projects.
Additional affiliations
January 2010 - November 2013
University of the Western Cape
Position
  • PhD Student
January 2008 - present
University of the Western Cape
Position
  • Clinical Science Coordinator
Description
  • Lecturer and co-ordinator of clinical science modules: Pathology, General Medicine, Clinical Diagnosis and Differential Diagnostics. I also teachcomponents of research methodology modules.

Publications

Publications (58)
Article
Research question Has seminal oxidation-reduction potential (ORP) clinical relevance for reproductive outcome. Design In this prospective observational study a total of 144 couples who had an ICSI cycle between June 2018 and December 2020 were included. The study included patients undergoing fresh ICSI cycles with autologous gametes. Cycles that h...
Article
Full-text available
Sperm vitality testing is a basic semen examination that has been described in the World Health Organization (WHO) Laboratory Manual for the Examination and Processing of Human Semen from its primary edition, 40 years ago. Several methods can be used to test sperm vitality, such as the eosin-nigrosin (E-N) stain or the hypoosmotic swelling (HOS) te...
Article
Full-text available
Purpose: This study provides a comprehensive analysis of research trends on the etiology, mechanisms, potential risk factors, diagnosis, prognosis, surgical and non-surgical treatment of varicocele, and clinical outcomes before and after varicocele repair. Materials and methods: Varicocele studies published between 1988 and 2020 were retrieved f...
Article
Full-text available
Antisperm antibodies (ASA), as a cause of male infertility, have been detected in infertile males as early as 1954. Multiple causes of ASA production have been identified, and they are due to an abnormal exposure of mature germ cells to the immune system. ASA testing (with mixed anti-globulin reaction, and immunobead binding test) was described in...
Chapter
Reactive oxygen species (ROS) are critical physiological mediators of cellular function, including male fertility. When ROS exceed antioxidant regulation, oxidative stress occurs which is detrimental to cellular function. Oxidative stress has been found to be a central mediator of obesity, metabolic syndrome (MetS) and type 2 diabetes mellitus (T2D...
Article
Full-text available
Androgens have diverse functions in muscle physiology, lean body mass, the regulation of adipose tissue, bone density, neurocognitive regulation, and spermatogenesis, the male reproductive and sexual function. Male hypogonadism, characterized by reduced testosterone, is commonly seen in ageing males, and has a complex relationship as a risk factor...
Article
To identify the most prevalent chromosomal abnormalities in patients with non‐obstructive azoospermia (NOA), consolidate their surgical sperm retrieval (SSR) rates and determine the significant predictors of positive SSR in this patient population. A systematic review and meta‐analysis were performed following the Preferred Reporting Items for Syst...
Article
Full-text available
Background : The use of herbal medicine and alternative medicine is reported to be in up to 50% of prescriptions for benign prostate hyperplasia (BPH) in Europe, along with an increased global interest for holistic medicinal approaches. This study aimed to systematically review the published evidence investigating the use of herbal medicines as a t...
Article
Full-text available
Purpose: In response to the COVID-19 pandemic, the American Center for Reproductive Medicine (ACRM) transitioned its annual training in assisted reproductive technology (ART) from a hands-on, laboratory-based training course to a fully online training endorsed by the American College of Embryology. Here we describe our experience and assess the qu...
Article
Full-text available
Objective The COVID-19 pandemic, caused by the acute respiratory syndrome-coronavirus 2 (SARS-CoV-2), remains an ongoing public health challenge. Although males are affected slightly more than females, the impact of SARS-COV-2 on male reproductive system remains unclear. This systematic review aims to provide a concise update on the effects of COVI...
Article
Full-text available
Purpose: The use of antioxidants is common practice in the management of infertile patients. However, there are no established guidelines by professional societies on antioxidant use for male infertility. Materials and methods: Using an online survey, this study aimed to evaluate the practice pattern of reproductive specialists to determine the...
Article
Full-text available
Background: Computer-aided sperm analyzers (CASA) are currently used worldwide for semen analysis. However, there are doubts about their reliability to fully substitute the human operator. Therefore, this study aimed to systematically review the current literature comparing results from semen evaluation by both CASA-based and manual approaches. Met...
Article
Full-text available
Objectives: To systematically review and discuss the current evidence from placebo-controlled clinical trials that investigated the use of alternative medicines and herbal remedies in the management of erectile dysfunction (ED). Methods: A Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)-based systematic review using spec...
Article
Full-text available
It is widely accepted that oxidative stress plays an important role in the pathophysiology of male infertility and that antioxidants could have a significant role in the treatment of male infertility. The main objectives of this study are: 1) to systematically review the current evidence for the utility of antioxidants in the treatment of male infe...
Article
Purpose: The objective of this scientometric analysis was to recognize the top 100 cited articles on 'Male infertility and Antioxidants' and analyze its publication characteristics. Materials and methods: The Scopus database was used to retrieve related articles and the top 100 identified based on citation rate. Results: The articles were publ...
Article
Obesity is considered a global health problem affecting more than a third of the population. Complications of obesity include cardiovascular diseases, type 2 diabetes mellitus, malignancy (including prostatic cancer), neurodegeneration and accelerated ageing. In males, these further include erectile dysfunction, poor semen quality and subclinical p...
Article
In 2020, the COVID‐19 pandemic led to the suspension of the annual Summer Internship at the American Center for Reproductive Medicine (ACRM). To transit it into an online format, an inaugural 6‐week 2020 ACRM Online Mentorship Program was developed focusing on five core pillars of andrology research: scientific writing, scientific methodology, plag...
Article
Autoimmune disorders currently affect 5–8% of the global population, characterized by an aberrant chronic inflammatory response to self‐antigens. The aim of this study was to systematically review the current available evidence investigating the impact of systemic autoimmune diseases and associated immunosuppressive treatment on fertility parameter...
Chapter
Pycnogenol, produced from Pinus pinaster (French maritime pine) extractions, is a significant source of medicinal procyanidins with OS and immune-modulating properties. Limited studies suggest a role in protection against induced spermatotoxicity through improved OS markers, and may improve fertility outcomes of subfertile males. However, the most...
Chapter
Since ancient times, man has benefited immensely from using natural resources to effectively address his needs; ranging from housing to utensils to food and even as medicine. Within this context, the human-plant interface plays an important role in our discovery of the medicinal value of plants thereby unlocking its therapeutic potential. The quest...
Chapter
Herbal medicines are complex compounds with multiple synergistic mechanisms of action that modulate (patho)physiological functions. Pharmacognosy is the study of medicine derived from natural sources that include plants, animals, and microorganisms, and the scope of the field depends on knowledge about the safety, purity, and efficacy of complex mu...
Article
Full-text available
Oxidative stress is a condition due to an imbalance between the concentrations of oxidants and antioxidants, and it is a wellrecognized contributor in several male infertility conditions. Varicocele, a common vascular condition, may cause male infertility due to hyperthermia, hypoxia and/or exposure to toxic adrenal and renal metabolites. In this r...
Article
Obesity is a significant global health and socio-economic challenge, and considered an important risk factor for poor health outcomes including male reproductive dysfunction and infertility. As excess adiposity causes testicular dysfunction and infertility, novel therapeutic strategies require investigation. Nigella sativa (Ns) seed oil and metform...
Article
Full-text available
Assisted reproductive technologies (ART) are considered as one of the primary mana gement options to address severe male factor infertility. The purpose of this study was to identify the research trends in the field of male infertility and ART over the past 20 years (2000-2019) by analysing scientometric data (the number of publications per year, a...
Article
Full-text available
Sperm DNA integrity is crucial for fertilization and development of healthy offspring. The spermatozoon undergoes extensive molecular remodeling of its nucleus during later phases of spermatogenesis, which imparts compaction and protects the genetic content. Testicular (defective maturation and abortive apoptosis) and post-testicular (oxidative str...
Article
Full-text available
Purpose: Since its discovery in December 2019, the novel coronavirus SARS-CoV-2 has spread globally, causing the current COVID-19 (coronavirus disease-19) pandemic. As there is an increase of infections in the male population, concerns have emerged about the potential impact of COVID-19 on male reproductive organs and male fertility. Therefore, th...
Chapter
• ROS are important physiological mediators of male fertility, sperm maturation, and fertilization. • Excessive ROS disrupts spermatogenesis, semen quality, steroidogenesis, and sexual functions. • Endogenous ROS in the male reproductive tract predominantly arises through immature spermatozoa and leukocytes. • Exogenous ROS resulting in reproduc...
Article
Alongside an increasing prevalence of couple and male infertility, evidence suggests there is a global declining trend in male fertility parameters over the past few decades. This may, at least in part, be explained through detrimental lifestyle practices and exposures. These include alcohol and tobacco consumption, use of recreational drugs (e.g.,...
Chapter
Male infertility is increasing in recent decades, affecting 7% of males during their reproductive life. The standard semen analysis remains widely used, specifically sperm concentration, motility, viability, and normal sperm morphology. However, this analysis is limited in clinical usefulness without information of the functional capacity of the sp...
Chapter
Male infertility currently has an increasing incidence globally while affecting 13–18% of males in their lifetime. Well-defined etiologies of male infertility are broad, with numerous underlying lifestyle and environmental risk factors established. Importantly, a significant proportion of male infertility remains idiopathic or unexplained. Lifestyl...
Article
Plagiarism is a common form of academic misconduct that extensively jeopardises the quality of scientific publication. The purpose of this study is to determine the extent of plagiarism in the most influential andrology articles. A total of 77 highly cited andrology articles were analysed for their similarity index using iThenticate and Turnitin. T...
Article
Full-text available
Despite advances in the field of male reproductive health, idiopathic male infertility, in which a man has altered semen characteristics without an identifiable cause and there is no female factor infertility, remains a challenging condition to diagnose and manage. Increasing evidence suggests that oxidative stress (OS) plays an independent role in...
Article
Obesity and metabolic syndrome (MetS) are global epidemics, driven by an obesogenic environment. This is mediated by complex underlying pathophysiology, in which chronic inflammation is an important aetiological and mechanistic phenomenon. A shift towards a sub‐clinical TH1–lymphocyte mediated innate and chronic inflammatory response is well define...
Poster
Full-text available
The act of using words, data, processes or even ideas from another person without acknowledging the source or giving appropriate credit is referred to as plagiarism. It is a serious issue that could profoundly compromise the quality of a scientific publication. Several journals have published reviews on plagiarism, however, there is a lack of trans...
Article
Full-text available
Despite advances in the field of male reproductive health, idiopathic male infertility, in which a man has altered semen characteristics without an identifiable cause and there is no female factor infertility, remains a challenging condition to diag- nose and manage. Increasing evidence suggests that oxidative stress (OS) plays an independent role...
Article
Full-text available
Purpose: Male infertility is emerging as a major, escalating global health problem that imposes the need to investigate research trends in male infertility. The purpose of this study is to analyze male infertility research trends in the past 20 years using the bibliometric database from Scopus. Materials and methods: In order to perform an in-de...
Article
Full-text available
Background: Cytokines and hormones, including insulin, are known to modulate the hypothalamic-pituitary-testes axis and steroidogenesis, both centrally and peripherally. In the context of chronic inflammation and hyperinsulinaemia mediating male hypogonadism associated with obesity, metabolic syndrome and type 2 diabetes mellitus, these mechanisms...
Article
Problem: The impact of metabolic syndrome (MetS) associated systemic inflammation on the male reproductive tract requires further investigation. Method of study: A cross-sectional case-controlled study design consisting of a control group (n=32) and a MetS (n=42) group was used. Variables include MetS diagnostic criterion, serum C-Reactive Prote...
Poster
Full-text available
hCG stimulated TM3 Leydig cells were exposed to concentrations of TNFα, IL1ß, IL6 and IL8 (0.1, 1, 10 and 100 ng/ml) and insulin (0.01, 0.1, 1 and 10 ng/ml) in optimal cell culture conditions. Cell viability, protein, testosterone and progesterone concentrations were assessed. INTRODUCTION Obesity and metabolic syndrome (MetS) in males is associate...
Article
Full-text available
Background Obesity appears to be associated with male reproductive dysfunction and infertility, although this has been inconsistent and inconclusive. Insulin and leptin are known mediators and modulators of the hypothalamus-pituitary-testes axis, contributing to the regulation of male reproductive potential and overall wellbeing. These hormones are...
Article
The metabolic syndrome (MetS) is a constellation of various risk factors. This study aimed to investigate the effect of MetS on testosterone and progesterone, and semen parameters, in a case-controlled pilot study. Male patients (n = 54) had body mass index, waist-to-hip ratio (WHR) and blood pressure recorded. Blood was analysed for HDL cholestero...
Article
Nutritional value of Dorper (n=10) and Merino (n=10) by-products were evaluated. Proximate composition differed between organs and breeds with Merino heart (68.9g/100g), spleen (77.2g/100g) and testicles (83.7g/100g) having higher moisture contents than their Dorper counterparts. Dorper brain (10.1g/100g), heart (15.2g/100g), spleen (20.4g/100g) an...
Cover Page
Full-text available
Overview of Reproductive Research 1993-2021

Network

Cited By