Male Reproduction Health Research Papers (original) (raw)

Let's start with some biological reductionism, provided in generous helpings by E. O. Wilson in Sociobiology: the New Synthesis (1975). In his retort to Wilson's work, The Use and Abuse of Biology, Marshall Sahlins underlined his... more

Let's start with some biological reductionism, provided in generous helpings by E. O. Wilson in Sociobiology: the New Synthesis (1975). In his retort to Wilson's work, The Use and Abuse of Biology, Marshall Sahlins underlined his belief that " the theory of sociobiology has an intrinsic ideological dimension, in fact a profound historical relation to Western competitive capitalism " (1977:

Hypospadias is a relatively common genital condition in which the urethral opening forms on the underside of the penis, as opposed to at the tip of the glans. Patients with hypospadias are typically referred for surgery during infancy or... more

Hypospadias is a relatively common genital condition in which the urethral opening forms on the underside of the penis, as opposed to at the tip of the glans. Patients with hypospadias are typically referred for surgery during infancy or early childhood. Recent evidence, however, indicates that many individuals with hypospadias do not experience the functional or psychosocial difficulties that are commonly attributed to the condition, and that surgical intervention for hypospadias carries substantial risk of adverse outcomes. In this article, we review published outcomes data and conduct an in-depth analysis of the typical rationales for hypospadias surgery, taking into consideration both the potential benefits and harms of the procedure, as well as the existence of non-surgical alternatives. We argue, firstly, that most childhood surgeries for hypospadias are performed for anticipated future problems concerning function and cosmesis, rather than extant problems that serve to undermine the child’s well-being. Secondly, we contend that the surgery can be safely performed after an age of consent without increasing the absolute risk of surgical complications to an ethically meaningful degree. We conclude that surgery for hypospadias should typically be performed only if requested by the affected individual, under conditions of informed consent.

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The sexual behavior and semen production potential of Surti buffalo bulls was investigated in this study.

The global scenario reveals that the recent trend of deterioration of male fertility parameters parallels the growing prevalence of obesity. Over the last few decades, substantial research evidence has surfaced that aid understanding of... more

The global scenario reveals that the recent trend of deterioration of male fertility parameters
parallels the growing prevalence of obesity. Over the last few decades, substantial research
evidence has surfaced that aid understanding of the mechanisms by which body energy
homeostasis is associated with reproductive functions. In this regard, leptin, an adipocytederived hormone, finds utmost relevance for its versatile physiological functions
especially in metabolism as well as in the regulation of reproductive functions. Since
leptin receptors are found to be highly expressed in several structures, both centrally and
peripherally, it has been hypothesized that leptin may affect reproductive functions either
via the hypothalamic-pituitary-gonadal axis or may also directly act upon gonadal tissues.
Its roles, particularly during puberty and reproduction, are well documented. However,
the exact mechanisms of leptin actions upon the gonadotropin-releasing hormone neurons
to induce physiological changes of puberty and reproduction need further research.
Leptin is proven as an essential hormone required for normal reproductive functions, but
when leptin levels exceed the physiological limit, it may adversely affect the testicular
processes. Leptin can serve as a potential link between obesity and male infertility, as
it has been shown that poor male reproductive parameters such as low sperm count,
testicular oxidative stress, high rate of morphological abnormalities in sperm, positively
correlate with increased levels of leptin in obese men. Therefore, the present review article
aims to provide a better understanding of the updated views on the functions of leptin and
mechanisms of leptin actions on male reproduction.

He has a PhD in male reproductive physiology from the University of Calcutta, India and over 24 peer reviewed publications in PubMed. He is a collaborating scientist with the American Center for Reproductive Medicine at Cleveland Clinic.... more

He has a PhD in male reproductive physiology from the University of Calcutta, India and over 24 peer reviewed publications in PubMed. He is a collaborating scientist with the American Center for Reproductive Medicine at Cleveland Clinic. KEY MESSAGE Withania sominifera roots improve semen quality by increasing sperm count and motility, regulating reproductive hormone levels and inhibiting lipid peroxidation. Proposed mechanisms underlying these effects are direct alleviation of oxidative stress and enhancement of hormonal balance via the gamma-aminobutyric acid-like mimetic pathway. Withania sominifera could potentially supplement routine treatment of male infertility. A B S T R A C T To manage male infertility caused by hormonal imbalance, infections and other predicaments, multifarious treatment strategies are emerging worldwide. Contemporary treatments, such as assisted reproductive techniques, are costly with low success rates of only 10–30%; however, herbal remedies are gaining more attention as an alternative or supplementary therapeutic modality for male infertility. The beneficial effects induced by oral intake of the roots of a small evergreen shrub, Withania sominifera (Ashwagandha) on semen quality of infertile men have previously been studied. Oral intake of Ashwagandha roots has been found to inhibit lipid peroxidation, improve sperm count and motility, and regulate reproductive hormone levels. The molecular mechanisms of these effects, however, are yet to be unveiled.

Sertoli cells play a key role in the establishment of an adequate luminal environment in the seminiferous tubules of the male reproductive tract. Secretion of the seminiferous tubular fluid (STF) is vital for the normal occurrence of... more

Sertoli cells play a key role in the establishment of an adequate luminal environment in the seminiferous tubules of the male reproductive tract. Secretion of the seminiferous tubular fluid (STF) is vital for the normal occurrence of spermatogenesis and for providing a means of transport to the developing spermatozoa. However, several studies on this subject have not completely clarified the origin and composition of this fluid. Electrolyte and water are central components of STF. Sertoli cells secrete an iso-osmotic fluid with a higher content of K+ than the blood and express various membrane and water transporters (Na+/K+-ATPase; Ca2+-ATPase; V-type ATPase; Cl− channels; CFTR Cl− channels; K+ channels; L-, T- and N-type Ca2+ channels; Na+/H+ exchangers; Na+-driven HCO3−/Cl− exchangers (NDCBEs); Na+/HCO3− cotransporters (NBCes); Na+–K+–2Cl− cotransporter; Na+/Ca2+ exchanger; and aquaporins 0 and 8) involved in cellular and secretory functions. Studies with knockout mice for some of these transporters showed tubular fluid accumulation and associated infertility, revealing the relevance of these processes for the normal occurrence of spermatogenesis. Nevertheless, the role of the several membrane transporters in the establishment of STF electrolyte composition needs to be further elucidated. This review summarizes the available data on the ionic composition of STF and on the Sertoli cell membrane mechanisms responsible for ion and water movement. Deepening the knowledge on the mechanisms involved in the secretion, composition and regulation of SFT is essential and will be a major step in understanding the infertility associated with some pathological conditions.

The anatomy of the internal organs of the male reproductive apparatus (MRA) of adults and pupae was compared among 51 species of bees, including representatives of six families. Four different types of MRA were found. The type I is... more

The anatomy of the internal organs of the male reproductive apparatus (MRA) of adults and pupae was compared among 51 species of bees, including representatives of six families. Four different types of MRA were found. The type I is present in males of the less derived families (Colletidae, Andrenidae, and Halictidae) and is characterized by three seminiferous tubules per testis, which are almost completely enveloped by the scrotal membrane. The type II is an intermediary between types III and I and is present in Melittidae and Megachilidae, as well as in some Apidae studied, being characterized by post-vesicular deferent ducts outside the scrotal membrane and by three or four seminiferous tubules per testis, except for Apis mellifera L., which has a secondarily increased number of tubules. Type III was only found in the Apidae studied and is characterized by separately encapsulated testes and genital ducts (except for the post-vesicular deferent duct). Accessory glands are well developed, and the ejaculatory duct is thickened with fissures in its wall, which may also occur in the type II. Type IV is present exclusively in the tribe Meliponini, and is characterized by the absence of accessory glands.

Endogenous and environmental estrogens have been proved to affect male reproduction in vertebrates. Both positive and negative effects in the regulation of the reproductive tract have been described. Since it is well known that amphibians... more

Endogenous and environmental estrogens have been proved to affect male reproduction in vertebrates. Both positive and negative effects in the regulation of the reproductive tract have been described. Since it is well known that amphibians represent a useful model to study several aspects concerning reproductive activity, we have taken advantage of the frog, Rana esculenta, to study the involvement of estrogens in sperm release. We show here that pituitary hormones increased the number of peritubular myoid cells (PMCs) expressing Fra-1 and induced testicular morphological changes related to sperm release. The estrogen antagonist ICI182-780 counteracted the hypophysis driven effects. In vivo and in vitro experiments demonstrated that 17β-Estradiol acted directly on the testis to switch-on Fra-1 in PMCs. Furthermore, impairment of estrogen activity significantly reduced sperm release mainly affecting the detachment of spermatozoa from Sertoli cells (spermiation). Therefore, estrogens c...

Evidence supporting a role for estrogen in male reproductive tract development and function has been collected from rodents and humans. These studies fall into three categories: i) localization of aromatase and the target protein for... more

Evidence supporting a role for estrogen in male reproductive tract development and function has been collected from rodents and humans. These studies fall into three categories: i) localization of aromatase and the target protein for estrogen (ER-alpha and ER-beta) in tissues of the reproductive tract; ii) analysis of testicular phenotypes in transgenic mice deficient in aromatase, ER-alpha and/or ER-beta gene; and, iii) investigation of the effects of environmental chemicals on male reproduction. Estrogen is thought to have a regulatory role in the testis because estrogen biosynthesis occurs in testicular cells and the absence of ERs caused adverse effects on spermatogenesis and steroidogenesis. Moreover, several chemicals that are present in the environment, designated xenoestrogens because they have the ability to bind and activate ERs, are known to affect testicular gene expression. However, studies of estrogen action are confounded by a number of factors, including the inabilit...

Morphometric characterization of twelve geographic populations of cotton bollworm, Helicoverpa armigera occurring in south Indian cotton ecosystems was done at larval, pupal and adult stages over three cropping seasons. Traits such as... more

Morphometric characterization of twelve geographic populations of cotton bollworm, Helicoverpa armigera occurring in south Indian cotton ecosystems was done at larval, pupal and adult stages over three cropping seasons. Traits such as length and weight of larvae, pupa and length and width of the wing, length of fore-, mid- and hind femur, male reproductive organ-length of genital capsule, valves, and ejaculatory duct, female reproductive organ-length of appendix bursae and ductus bursae at adult stage were measured across three years. Populations significantly differed for most of the traits studied. It was evident that populations from northern parts recorded higher phenotypic attributes compared to those from southern parts of south Indian cotton ecosystem. Besides larval, pupal and adult external phenotypic traits, attributes of male reproductive organ viz., length of genital capsule, valves, and ejaculatory duct and female reproductive organ viz., length of appendix bursae and ductus bursae differed significantly among populations. Information on population structure and differences based on morphometry would be useful in better understanding of population dynamics and management of this pest in cotton and other crops in south India.

The effect of the Caprine Arthritis Encephalitis Virus (CAEV) on the reproductive system of the male goat was evaluated. Fourteen adult males distributed into 4 groups were studied: I) negative control (uninfected animals) (n=3); II)... more

The effect of the Caprine Arthritis Encephalitis Virus (CAEV) on the reproductive system of the male goat was evaluated. Fourteen adult males distributed into 4 groups were studied: I) negative control (uninfected animals) (n=3); II) animals experimentally infected with an autochthonous CAEV (FES-C.UNAM isolate) (n=3); III) naturally infected animals (n=5); IV) animals experimentally infected with CAEV reference strain from the American Type Culture Collection (ATCC) (n=3). Blood and semen samples were collected every 30 days and ani- mals were clinically evaluated (especially for possible external genital alterations) during 10 months. No differences in scrotal diameter, seminal motility, seminal pH, color and volume were found among the four groups. Antibodies against CAEV were detected by ELISA in blood serum and seminal fl uid in animals infected with the autochthonous strain after 7 months, in animals experimentally infected with the reference strain after 3 months and animals ...