Reproductive success is dependent on gamete integrity, and oxidative stress alters male nuclei, meaning that no DNA repair is possible due to chromatin compaction. The composition of sperm makes it highly sensitive to reactive oxygen species (ROS) but, at the same time, ROS are needed for sperm physiology. Over the past 30 years, much attention has been paid to the consequences of oxidative stress on sperm properties and the protective effects of antioxidant formulations to help fertility.
View Article and Find Full Text PDFJ Comp Physiol A Neuroethol Sens Neural Behav Physiol
May 2024
In mammals, especially rodents, social behaviours, such as parenting, territoriality or mate attraction, are largely based on olfactory communication through chemosignals. These behaviours are mediated by species-specific chemosignals, including small organic molecules and proteins that are secreted in the urine or in various fluids from exocrine glands. Chemosignal detection is mainly ensured by olfactory neurons in two specific sensory organs, the vomeronasal organ (VNO) and the main olfactory epithelium (MOE).
View Article and Find Full Text PDFLong considered an accessory tubule of the male reproductive system, the epididymis is proving to be a key determinant of male fertility. In addition to its secretory role in ensuring functional maturation and survival of spermatozoa, the epididymis has a complex immune function. Indeed, it must manage both peripheral tolerance to sperm antigens foreign to the immune system and the protection of spermatozoa as well as the organ itself against pathogens ascending the epididymal tubule.
View Article and Find Full Text PDFRoutine exposure to chemicals omnipresent in the environment, particularly the so-called endocrine-disrupting chemicals (EDCs), has been associated with decreased sperm quality and increased anomalies in testis. The decline in semen quality and testicular abnormalities have been attributed to the disruption of endocrine signaling as well as oxidative stress. The present study set out to examine the effect of short-term exposure of two common EDCs widely used in the plastic industry: Dibutyl Phthalate (DBP) and Bisphenol AF (BPAF).
View Article and Find Full Text PDFPurpose: High success rates and minimal complications have consolidated arthroscopy as the therapeutic alternative of choice for minimally invasive treatment of internal disorders (ID) of the temporomandibular joint (TMJ). However, there is no certainty regarding the demographic and clinical factors associated with the technique's success or failure. This study was performed to analyze the effectiveness of arthroscopy regarding pain and the mandibular dynamics and also to determine whether variables such as age, sex, and preoperative Wilkes stage influence the results.
View Article and Find Full Text PDFBackground: The optimization of spermatozoa preparation techniques in order to obtain cell fractions enriched with structurally and functionally "superior" spermatozoa is a key objective of the assisted reproduction industry.
Objectives: The purpose of this study was to evaluate a recent development of an electrophoretic spermatozoa separation device (Felix™, Memphasys Ltd, Sydney, Australia) and to compare its performance with conventional spermatozoa preparation by density gradient centrifugation (DGC). Particular attention was paid to the evaluation of sperm DNA/nuclear integrity.
In mammals, sperm fertilization potential relies on efficient progression within the female genital tract to reach and fertilize the oocyte. This fundamental property is supported by the flagellum, an evolutionarily conserved organelle that provides the mechanical force for sperm propulsion and motility. Importantly several functional maturation events that occur during the journey of the sperm cells through the genital tracts are necessary for the activation of flagellar beating and the acquisition of fertilization potential.
View Article and Find Full Text PDFTesticular Germ Cell Tumours (TGCT) are widely considered a "curable cancer" due to their exceptionally high survival rate, even if it is reduced by many years after the diagnosis due to metastases and relapses. The most common therapeutic approach to TGCTs has not changed in the last 50 years despite its multiple long-term side effects, and because it is the most common malignancy in young Caucasian men, much research is needed to better the quality of life of the many survivors. Proprotein Convertases (PC) are nine serine proteases responsible for the maturation of inactive proproteins with many diverse functions.
View Article and Find Full Text PDFSmall Bus Econ (Dordr)
March 2021
Abstract: The relative importance of small- and medium-sized enterprises (SMEs) and large firms is a recurrent topic in the small business economics literature. This paper presents a real and financial social accounting matrix (FSAM) capable of distinguishing the direct and indirect effects that are transferred from micro-, small, medium, and large firms to the rest of the economy. We use the hypothetical extraction method (HEM) to explore the sequence of reactions associated with shocks that arise from the COVID-19 lockdown.
View Article and Find Full Text PDFGlobozoospermia is a type of teratozoospermia characterized by round morphology of the sperm head. Gopc infertile globozoospermic murine model has failures during spermiogenesis, such as the incorrect biogenesis of the acrosome, disorganized acroplaxome and manchette, round nuclei and spiral flagella. In this study, Western blot, RT-PCR, immunohistochemistry and immunogold were done for the localization of the acrosome protein Zona Pellucida sperm-binding protein 3 receptor (ZP3R), also called sp56, in wild type and Gopc mice testis.
View Article and Find Full Text PDFHydrogen sulfide (HS) plays several physiological roles in plants. Despite the evidence, the role of HS on cell wall disassembly and its implications on fleshy fruit firmness remains unknown. In this work, the effect of HS treatment on the shelf-life, cell wall polymers and cell wall modifying-related gene expression of Chilean strawberry () fruit was tested during postharvest storage.
View Article and Find Full Text PDFMammals living at temperate latitudes typically display annual cyclicity in their reproductive activity: births are synchronized when environmental conditions are most favorable. In a majority of these species, day length is the main proximate factor used to anticipate seasonal changes and to adapt physiology. The brain integrates this photoperiodic signal through key hypothalamic structures, which regulate the reproductive axis.
View Article and Find Full Text PDFAm J Physiol Renal Physiol
September 2021
Dahl salt-sensitive (SS) rat kidneys produce less nitric oxide (NO) than those of salt-resistant (SR) rats. Thick ascending limb (TAL) NO synthase 3 (NOS3) is a major source of renal NO, and luminal flow enhances its activity. We hypothesized that flow-induced NO is reduced in TALs from SS rats primarily due to NOS uncoupling and diminished NOS3 expression rather than scavenging.
View Article and Find Full Text PDFSeasonally breeding mammals display timely physiological switches between reproductive activity and sexual rest, which ensure synchronisation of births at the most favourable time of the year. These switches correlate with seasonal changes along the hypothalamo-pituitary-gonadal axis, but they are primarily orchestrated at the hypothalamic level through environmental control of KISS1-dependent GnRH release. Our field study shows that births of fossorial water voles, Arvicola terrestris, are concentrated between March and October, which indicates the existence of an annual reproductive cycle in this species.
View Article and Find Full Text PDFBackground: Seminal plasma (SP) plays a crucial role in sperm protection and functionality. However, the effect of SP on the sperm cryopreservation is dependent on the stallion and SP composition. The use of epididymal spermatozoa incubated in the presence of SP could help the identification of the components of SP that are able to confer protection upon the spermatozoa during freezing.
View Article and Find Full Text PDFMany studies have been conducted to determine the composition of the glycoconjugates of the mucus-secreting cells of the fundic glands of the stomach. However, the chief cells of these glands have been largely ignored because they secrete mainly zymogens with a lower glycosylation. The aim of this work was to analyze the glycoconjugates of the gastric chief cells by a battery of 17 different lectins, recognizing Fucose, N-acetylgalactosamine, Galactose, N-acetylneuraminic acid, N-acetylglucosamine and Mannose containing oligosaccharides.
View Article and Find Full Text PDFTestes produce spermatozoa that transit through and are stored in the epididymis where they acquire their fertilising capacities. Spermatozoa appear in the genital tract at puberty, long after the immune system was trained to self-antigens. As a consequence, this organ has to set strategies to tolerate sperm antigens to avoid autoimmune responses that would specifically target and destroy them.
View Article and Find Full Text PDFLipid metabolic disorders due to poor eating habits are on the rise in both developed and developing countries, with a negative impact of the "Western diet" on sperm count and quality. Dietary lipid imbalance can involve cholesterol, fatty acids, or both, under different pathophysiological conditions grouped under the term dyslipidemia. The general feature of dyslipidemia is the development of systemic oxidative stress, a well-known deleterious factor for the quality of male gametes and associated with infertility.
View Article and Find Full Text PDFMechanical stretch raises intracellular Ca (Ca) in many cell types. Luminal flow-derived stretch stimulates O production by thick ascending limbs (THALs). Renal O is greater in Dahl salt-sensitive (SS) than salt-resistant (SR) rats.
View Article and Find Full Text PDFIntussusception in lymphatic vessels has received less attention than in blood vessels. In tumors and pseudotumors of blood vessels with intravascular papillary structures, including sinusoidal hemangioma and intravascular papillary endothelial hyperplasia, we observed exuberant intussusceptive angiogenesis, as well as the similarity between papillae (term used by pathologists) and pillars/folds (hallmarks of intussusceptive angiogenesis). A similar response could be expected in lymphangiomas (lymphatic malformations and reactive processes rather than tumors) with papillae.
View Article and Find Full Text PDFBackground: Lipid metabolic disorders (dyslipidemia) are constantly increasing in occidental societies and lead to the development of pathologies such as obesity, diabetes, and metabolic syndrome. It has been demonstrated that dyslipidemia can alter the reproductive function. Animal models have recently been used to show that the offspring of dyslipidemic males could also develop such pathologies and that the transgenerational transmission involved post-testicular sperm maturation.
View Article and Find Full Text PDFBackground: One third of infertility cases in couples worldwide has an exclusive male origin and immune disorders, essentially due to repetitive infections, are emerging an cause of male infertility. As the place of sperm maturation, epididymis must be preserved from excessive immune responses that may arise following infections of the male genital tract. At the same time, epididymis must set and maintain a tolerogenic environment in order not to destroy sperm cells that enter the tissue at puberty, long after the immune system has been taught to recognize self pathogens.
View Article and Find Full Text PDFUp to 15% of male infertility has an immunological origin, either due to repetitive infections or to autoimmune responses mainly affecting the epididymis, prostate, and testis. Clinical observations and epidemiological data clearly contradict the idea that the testis confers immune protection to the whole male genital tract. As a consequence, the epididymis, in which posttesticular spermatozoa mature and are stored, has raised some interest in recent years when it comes to its immune mechanisms.
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