A5017257057- Sperm and Testicular Function
- Reproductive Biology and Fertility
- Genetic and Clinical Aspects of Sex Determination and Chromosomal Abnormalities
- Sexual Differentiation and Disorders
- Hormonal and reproductive studies
- Assisted Reproductive Technology and Twin Pregnancy
- Reproductive Health and Technologies
- Genetic and Kidney Cyst Diseases
- Prenatal Screening and Diagnostics
- Sexual function and dysfunction studies
- Hypothalamic control of reproductive hormones
- Hemoglobinopathies and Related Disorders
- Sexuality, Behavior, and Technology
- Ovarian function and disorders
- Parvovirus B19 Infection Studies
- Genomics and Chromatin Dynamics
- Plant Reproductive Biology
- Protist diversity and phylogeny
- DNA Repair Mechanisms
- Reproductive biology and impacts on aquatic species
- Pluripotent Stem Cells Research
- Eating Disorders and Behaviors
- Pharmacology and Obesity Treatment
- Medical and Health Sciences Research
- Iron Metabolism and Disorders
University of Münster
2015-2024
University Hospital Münster
2010-2024
Klinik für Schlafmedizin
2010
The infertility of many couples rests on an enigmatic dysfunction the man's sperm. To gain insight into underlying pathomechanisms, we assessed function sperm-specific multisubunit CatSper-channel complex in sperm almost 2,300 men undergoing a fertility workup, using simple motility-based test. We identified group with normal semen parameters but defective CatSper function. These or failed to conceive naturally and upon medically assisted reproduction via intrauterine insemination vitro...
Microsurgical testicular sperm extraction (mTESE), combined with intracytoplasmic injection (ICSI) represents a chance for azoospermic men Klinefelter's syndrome (KS) to father children. The objective of this study was identify predictive factors the success mTESE from adolescents and adults KS. clinical data 50 late pubertal (13-19 years) 85 adult patients (20-61 non-mosaic KS, who underwent mTESE, were analysed respect factors, potentially active spermatogenesis; specifically history...
Axonemal protein complexes, such as outer (ODA) and inner (IDA) dynein arms, are responsible for the generation regulation of flagellar ciliary beating. Studies in various ciliated model organisms have shown that axonemal arms first assembled cell cytoplasm then delivered into axonemes during ciliogenesis. In humans, mutations genes encoding factors involved this process cause structural functional defects motile cilia organs airways result hereditary disorder primary dyskinesia (PCD)....
Article19 January 2020Open Access Transparent process Rotational motion and rheotaxis of human sperm do not require functional CatSper channels transmembrane Ca2+ signaling Christian Schiffer Centre Reproductive Medicine Andrology, University Hospital Münster, Germany Search for more papers by this author Steffen Rieger Optical Technologies Group, Institute Applied Physics, Christoph Brenker Samuel Young Hussein Hamzeh orcid.org/0000-0002-3056-788X Molecular Sensory Systems, Center Advanced...
Abstract Life‐long sperm production leads to the assumption that male fecundity remains unchanged throughout life. However, recently it was shown paternal age has profound consequences for fertility and offspring health. Paternal effects are caused by an accumulation of germ cell mutations over time, causing severe congenital diseases. Apart from these well‐described cases, molecular patterns ageing in cells their impact on DNA integrity have not been studied detail. In this study, we aimed...
Primary Ciliary Dyskinesia (PCD) is a rare genetic disorder affecting the function of motile cilia in several organ systems. In PCD, male infertility caused by defective sperm flagella composition or deficient efferent ducts reproductive system. Different PCD-associated genes encoding axonemal components involved regulation ciliary and flagellar beating are also reported to cause due multiple morphological abnormalities (MMAF). Here, we performed testing next generation sequencing...
For most azoospermic men testicular sperm extraction (TESE) is the only treatment, however it presents challenges for ART laboratory, as retrieval of motile spermatozoa difficult. In absence movement no unequivocal distinction can be made between either dead or immotile, but vital spermatozoa. However, a single laser shot directed to tip tail allows recognition viability because flagellum coils at area impact. To rank quality and maturity oocytes, polarization microscopy used. The zona score...
The sperm-specific Ca2+ channel CatSper (cation of sperm) controls the influx into flagellum and, thereby, swimming behavior sperm. A hallmark human is its polymodal activation by membrane voltage, intracellular pH, and oviductal hormones. Whether also activated signaling pathways involving an increase cAMP ensuing PKA is, however, a matter controversy. To shed light on this question, we used kinetic ion-sensitive fluorometry, patch-clamp recordings, optochemistry to study transmembrane flux...
Do bi-allelic variants in the genes encoding MSH4/MSH5 heterodimer cause male infertility?We detected biallelic, (likely) pathogenic MSH5 (4 men) and MSH4 (3 six azoospermic men, demonstrating that genetic these are a relevant of infertility.MSH4 form heterodimer, which is required for prophase meiosis I. One variant two have been described as causal premature ovarian insufficiency (POI) total five women, resulting infertility. Recently, reported infertile men. So far, no had males.We...
Testosterone (T) therapy of hypogonadal men requires stable kinetics, tolerance and attenuation symptoms. Both intramuscular injections the long-acting ester T undecanoate (TU) transdermal application gel offer a proven efficacy. As has marked effects on hematopoiesis, an elevation hematocrit to be considered during therapy.To compare with TU controlling for age, diagnosis, androgen receptor susceptibility obesity.Prospective two-arm open registry, minimum duration 26 weeks per patient....
The longitudinal efficacy and clinical utility of Testosterone Therapy (TTh) in ameliorating functional hypogonadism (FH) remain contentious, with long-term data being scarce. To address this lacuna, a comprehensive registry study, stratifying patients across spectrum hypogonadal etiologies, offers robust investigative paradigm.
ATS indicates acute thorax syndrome; FI: feritlity index; S/T: spermatogonia per round tubular cross-section; Hb: hemoglobin; HbF: fetal HbS: sickle HU: hydroxyurea; y: year; x d: day; LDH: lactate dehydrogenase; MCV: mean corpuscular volume; P: P-value and r, Spearman correlation coefficient.*P<0.05.† Washout period of 2 weeks -4 months was used prior to biopsy for three HU-exposed patients.All 3 patients received transfusions.
Due to the highly variable clinical phenotype, Klinefelter Syndrome is underdiagnosed.
The infertility of many couples seems to rest on an enigmatic dysfunction the men’s sperm, rendering early diagnosis and evidence-based treatment by medically assisted reproduction impossible. Using a novel laboratory test, we assessed function flagellar Ca 2+ channel CatSper in sperm almost 2,300 men undergoing fertility workup. Thereby, identified group with mutations CATSPER genes affecting channel. Although standard semen computer-assisted analysis were unremarkable, required...
Does pituitary response to a GnRH stimulation test differ according the different FSHB-211 G/T genotypes?The promoter polymorphism G > T affects exogenous by reducing FSH and increasing LH outputs.The single nucleotide (SNP) is known affect output impairing transcriptional activity of FSHB.This was cross-sectional, retrospective study on 67 male subjects (mean age: 24.6 ± 10.3 years) undergoing for diagnostic purposes in cases secondary hypogonadism.A performed administering an i.v. bolus...
Abstract Children of older fathers have higher risk for certain diseases. Nevertheless, how ageing specifically affects male germ cells is so far not completely understood. In a cohort 197 healthy men (18-84 years), we found that semen and reproductive parameters remained normal over six decades. Along with an age-dependent increase in telomere length sperm (r=0.41, p>0.001), accelerated DNA fragmentation, more prominent after the sixth decate life, around 60% than 66 showing abnormal...
Abstract The sperm-specific CatSper channel controls the influx of Ca 2+ into flagellum and, thereby, swimming behavior sperm. A hallmark human is its polymodal activation by membrane voltage, intracellular pH, and oviductal hormones. Whether also activated signaling pathways involving an increase cAMP ensuing protein kinase (PKA) is, however, a matter controversy. Here, using kinetic ion-sensitive fluorimetry patch-clamp recordings, we study transmembrane flux currents in sperm from healthy...
In eukaryotes, the nucleocytoplasmic export of bulk poly(A)+-mRNAs through nuclear pore complex is mediated by ubiquitously expressed NXT1-NXF1 heterodimer. humans, NXT1 has an X-chromosomal paralog, NXT2, which exhibits testis-enriched expression, suggesting a role in spermatogenesis. Here, we report vivo interaction NXT2 with crucial components machinery, including NXF1, testis-specific NXF1 paralogs NXF2 and NXF3, proteins NUP93 NUP214. Further, NXT2's NTF2-like domain mediates binding to...
Summary This study examines spermatogonial numbers in testicular samples from 43 prepubertal patients undergoing haematopoietic stem cell transplantation (HSCT). High‐dose chemotherapy and/or radiation during HSCT can impact spermatogenesis requiring fertility preservation. Results show that 49% of have decreased and 19% severely depleted pool prior to HSCT. Patients with Fanconi anaemia exhibit significantly reduced numbers. immunodeficiency or aplastic generally present within the normal...