Search results for "sperma"
showing 10 items of 296 documents
Ag-NOR and C-banding analysis of spermatocyte chromosomes ofClavelina lepadiformis(Ascidiacea, Aplousobranchiata)
1991
SUMMARYChromosome number n = 9 and 2n = 18 for Clavelina lepadiformis (Ascidiacea, Aplousobranchiata) from the Gulf of Palermo have been determined. Silver staining analysis of testicular cells reveals that within-individual variability in NOR banding patterns is present. Using the C-banding procedure, a very impressive heterochromatin amount seems to characterize the chromosome set of this species.
Obstetric and Neonatal Outcome of Pregnancies Fathered by Males on Immunosuppression After Solid Organ Transplantation
2015
Immunosuppressive drugs may influence spermatogenesis, but little is known about outcome of pregnancies fathered by transplanted males. We estimated risk of adverse outcomes in pregnancies (with data after the first trimester) fathered by males that had undergone organ transplantation and were treated with immunosuppression. A population-based study, linking data from the Norwegian transplant registry and the Medical Birth Registry of Norway during 1967-2009 was designed. All Norwegian men undergoing solid organ transplantation were included. Odds ratios for major malformations, preeclampsia, preterm delivery (<37 weeks) and small-for-gestational-age were obtained using logistic regression.…
Die Leydigschen Zwischenzellen im Funiculus spermaticus des Menschen
1955
Innerhalb und an manchen Nervenstammchen des Funiculus spermaticus des Menschen konnten bei 13 untersuchten erwachsenen Mannern regelmasig beiderseitig in wechselnder Ausbildung Leydigsche Zwischenzellen aufgefunden werden. Sie liegen vorwiegend 4–7 cm uber den Hoden und zeigen jeweils alle charakteristischen Merkmale der Zwischenzellen des dazugehorigen Hodens. Eine authochtone Entstehung dieser Zellen aus dem ortlichen Bindegewebe oder aus den Schwannschen Zellen der Nerven wird ebenso wie eine Gleichsetzung dieser Zellkomplexe mit akzessorischem Nebennierenrindengewebe abgelehnt. Ein Vergleich mit den Lageverhaltnissen bei Feten last vermuten, das die Zellgruppen dem Hoden entstammen und…
Sperm DNA integrity and human papillomavirus (HPV) infections: a controversy that could be resolved by a new molecular approach
2020
Study question: The aim was to determine if HPVs affect spermatozoa DNA integrity. To resolve the discrepancy regarding the association between HPV infections and sperm DNA damage. Summary answer: To elucidate if HPV impairs DNA integrity, we suggest to investigate HPV DNA positivity in spermatozoa by a differential lysis procedure before TUNEL assay.
Novel indole alkaloids from cell suspension cultures of aspidosperma quebracho blanco schlecht
1991
Abstract Two novel monoterpenoid indole alkaloids, aspidochibine ( 1 ) and 3-oxo-14,15-dehydrorhazinilam ( 2 ), were isolated from cell suspension cultures of Aspidosperma quebracho blanco Schlecht. Aspidochibine ( 1 ) exhibits a new alkaloid skeleton. The structure of these alkaloids was elucidated by spectroscopic methods.
Male fertility in long-term survivors of childhood ALL.
1999
A study of fertility was conducted in postpubertal male patients who had been treated for acute lymphoblastic leukemia (ALL) during childhood or adolescence between 1970 and 1980. Thirteen men (age 18 to 35 years) participated on a volunteer basis. Their age at diagnosis was between 2 and 15 years. Therapy followed the protocol ''Memphis VII (Pinkel)." Interview, physical examination, andrological studies (ejaculate), and hormone status (luteinizing hormone, follicle-stimulating hormone, and testosterone) were performed at least 5 years after completion of therapy. No normozoospermia was achieved; 10 patients were identified with asthenozoospermia and 3 patients with azoospermia. With respe…
Sperm selection by swim-up in terms of deoxyribonucleic acid fragmentation as measured by the sperm chromatin dispersion test is altered in heavy smo…
2007
Toxic habits and their relationship with male factor infertility have been a matter of investigation in recent years, and smoking is one of the most common lifestyle toxic exposures to harmful substances. The analysis of sperm deoxyribonucleic acid fragmentation after capacitation detected a detrimental effect produced by tobacco, and this deleterious effect alters the sperm swim-up selection process in smokers, although the molecular and cellular basis of this phenomenon remain to be elucidated.
Sperm cryopreservation in oncological patients: a 14-year follow-up study.
2006
Objective Oncologic treatments can destroy spermatogenic dividing cells and cause azoospermia which could be irreversible. Sperm banking is the best option to preserve male fertility after these treatments. It is easy, inexpensive, and safe. To date, few clinical data are available about large series of cancer patients. Our objective was to determine the usefulness of these preventive sperm freezing protocols. Design Prospective study. Setting University-affiliated private fertility center. Patient(s) One hundred eighty-six cancer patients who banked sperm samples at our center before surgery or chemo- or radiotherapy treatments from 1991 to 2004. Intervention(s) Conjugal status, age, type …
Microarray analysis in sperm from fertile and infertile men without basic sperm analysis abnormalities reveals a significantly different transcriptom…
2007
Sperm analysis following World Health Organization guidelines is unable to explain the molecular causes of male infertility when basic sperm parameters are within a normal range and women do not present gynecologic pathology. Consequently, there is a need for accurate diagnostic tools in this area, and microarray technology emerges as promising. We present, for the first time, preliminary results of a comparison of sperm mRNA expression profiles between fertile and infertile men with normal semen parameters, discovering profound discrepancies between groups, with potential diagnostic and therapeutic possibilities.
Mechanisms involved in the transmission of epigenetic deregulation : analyses of transmission in human sperm
2018
The notion that environmental exposure can be memorized and promote epimutation (defined as defects on DNA methylation) raises the question of possible epigenetic transgenerational transmission in humans. To address whether an epimutation could be transmitted in humans, we pursued two axes. First, the evaluation of intergenerational transmission in the family of a Silver-Russell patient has shown, for the first time, the efficiency of epigenetic reprogramming in humans, specifically on imprinted regions. Indeed, no imprinted defect on causal H19/IGF2 locus was detected in the patient’s spermatozoa or in the DNA of his daughter. The second axis was to assess the presence of sperm epimutation…