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Query: UMLS:C0848676 (male subfertility)
 265 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Intracytoplasmic sperm injection (ICSI) is a very important technique for treating male subfertility and for basic research. The efficiency of ICSI in bovine is very limited because of the necessity for additional oocyte activation before or after the ICSI procedure. In this study, we compared the effects of seven different protocols on activation and fertilization rates of bovine oocytes after ICSI and on their subsequent development under in vitro conditions. The protocols include 1) different chemical activation of oocytes, 2) pretreated or nonpretreated sperm, and 3) conventional or Piezo-driven injection techniques. In all three groups, ICSI, sham-injected, and noninjected, the highest activation rates were obtained after treatment of oocytes with ionomycin followed by 6-dimethylaminopurine (6-DMAP). Using this treatment for oocyte activation, 59% of oocytes were activated and 31% of oocytes were fertilized using dithiothreitol (DTT) pretreated spermatozoa and Piezo-driven injection. Using the protocols with the same oocyte activation or activation with calcium ionophore (Ca-I) and cycloheximide (CHX), nonpretreated sperm, and conventional injection technique, early cleavage rate (79.6% and 77.6%, respectively) were significantly (P <0.01) higher when compared with all other protocols. The latter protocol resulted in 8% blastocyst and 90% of the obtained blastocysts were found to be diploid. Our results demonstrate that activation of oocytes, sperm treatment, and injection technique separately or together could improve the success of bovine ICSI.
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PMID:Intracytoplasmic sperm injection in bovine: effects of oocyte activation, sperm pretreatment and injection technique. 1109 46

Among the most popular techniques of assisted reproduction for the treatment of male subfertility and infertility are intrauterine insemination, in vitro fertilization and intracytoplasmic sperm injection. The objective of these techniques is to bring more functional spermatozoa closer to the oocyte in order to promote fertilization. These techniques are thus not a cure per se and are only indicated when no specific or effective treatment is available for the male partner, when this treatment has failed or when the improvement of the female fertility status has also failed. While for moderate oligoasthenozoospermia, intrauterine insemination has proved to be a valid treatment, the outcome after conventional in vitro fertilization is limited because of a high incidence of complete fertilization failure. Since the introduction of intracytoplasmic sperm injection, a reliable method has become available in order to achieve fertilization in vitro. Apart from well from ejaculated spermatozoa, epididymal or testicular spermatozoa too can be used successfully for intracytoplasmic sperm injection. The surgical retrieval of spermatozoa for intracytoplasmic sperm injection has therefore become a routine technique in clinical andrology. Although these techniques have been implemented in everyday infertility practice within a few years of their introduction, many concerns about safety continue to exist. Intracytoplasmic sperm injection must be applied with caution, only when no other treatment option is available and when an appropriate prospective follow-up of the offspring is available.
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PMID:Management of male infertility by assisted reproductive technologies. 1109 84

Ciliary function is essential for normal cellular activity in all species from simple protozoa upwards. In humans, ciliary dysmotility or complete immobility have been identified in autosomal recessive multisystemic diseases characterized by recurrent respiratory tract infections and male subfertility due to impaired sperm mobility. Linkage to human chromosome 19q13.3 has been published for some families but no candidate genes have been identified. We report the first identification of a mammalian homolog of a radial spokehead-like protein, with high homology to proteins of sea urchins and the protozoan Chlamydomonas reinhardtii, at the myotonic dystrophy-1 locus (chromosome19q13.3). In the lower organisms, these proteins are important in normal ciliary or flagellar action, including that of sea urchin spermatozoa. Expression of the mammalian homolog was detected in the adult testis. We suggest that this gene, which we have called Radial Spokehead-Like 1 (RSHL1), is a candidate gene for familial primary ciliary dyskinesia.
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PMID:A mammalian radial spokehead-like gene, RSHL1, at the myotonic dystrophy-1 locus. 1123 35

Treatment of severe male subfertility has become available since the intracytoplasmic injection of a single sperm into an oocyte was successfully applied for the first time in 1992. Moreover, with the use of fresh and cryopreserved epididymal and testicular spermatozoa for this procedure, fertilization and pregnancies could be accomplished. This review addresses the development and performance of these techniques and discusses achievements and problems as well as future aspects of the feasibility of early spermatid injection. Furthermore, limitations of these procedures and concerns with regard to genetic and epigenetic risks of using immature gametes are stressed.
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PMID:The use of cryopreserved mature and immature testicular spermatozoa for intracytoplasmic sperm injection: risks and limitations. 1194 32

Intracytoplasmic sperm injection (ICSI) entails the mechanical insertion of a chosen spermatozoon directly into the cytoplasm of an oocyte. Due to the consistent fertilization and pregnancy outcome, ICSI is routinely used to treat azoospermic patients where spermatozoa are retrieved by epididymal aspiration or testicular biopsy. Since male subfertility has been associated with a higher incidence of genomic defects, ranging from numerical chromosomal abnormalities to Yq microdeletions, concerns have been raised as to the risk of transmitting genetic defects to the offspring. Screening for such defects can provide invaluable information for appropriate counselling prior to ICSI treatment. In order to address these concerns, a follow-up of the children born after ICSI treatment was conducted.
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PMID:Application of intracytoplasmic sperm injection in assisted reproductive technologies. 1283 94

Artificial insemination (AI) is the oldest and currently most common technique in the assisted reproduction of animals and humans. The introduction of AI in farm animals was forced by sanitary reasons and the first large-scale applications with a commercial goal were performed in cattle in the late 1930s of last century. After the Second World War, cryopreservation of semen facilitated distribution and AI was mainly performed for economic reasons, especially in dairy cattle industry. In humans however, AI was initially performed in cases of physiological and psychological sexual dysfunction, but later on also in cases of infertility caused by immunological problems. Currently, the most common indications for intra-uterine insemination (IUI) in humans are unexplained infertility and male subfertility. In these cases, IUI is considered as the treatment of the first choice, before more invasive techniques such as in vitro fertilization (IVF) and intracytoplasmatic sperm injection (ICSI) are used. In contrast with humans, the quantity and quality of semen produced by farm animals is much higher and permits dilution and production of several insemination doses per ejaculate. However, with the introduction of sex-sorted semen in farm animals, the same problem of low-quality semen as in humans has arisen. In cattle, pigs and horses, conventional insemination with low numbers of sex-sorted spermatozoa results in a significant decrease in fertility. To improve the fertility rates with this semen, new insemination techniques have been developed in order to deposit spermatozoa closer to the site of fertilization. In sows and mares the advantage of utero-tubal junction (UTJ) insemination has already been proven; however, in cattle it is still under investigation. In this review, the differences and similarities in the application of AI between animals and humans are discussed and as AI in farm animals is most successful in cattle, the situation in this species is elaborated the most.
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PMID:Intra-uterine insemination in farm animals and humans. 1518 97

Treatment of severe male subfertility has become available since the intracytoplasmic injection of a single sperm into an oocyte was successfully applied for the first time in 1992. Moreover, with the use of fresh and cryopreserved epididymal and testicular spermatozoa for this procedure, fertilization and pregnancies could be accomplished. This review addresses the development and performance of these techniques and discusses achievements and problems as well as future aspects of the feasibility of early spermatid injection. Furthermore, limitations of these procedures and concerns with regard to genetic and epigenetic risks of using immature gametes are discussed.
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PMID:The use of cryopreserved mature and immature spermatozoa in assisted reproduction. 1525 32

Testicular torsion is a urological emergency referred to as 'acute scrotum', because inappropriate treatment can lead to male subfertility and infertility. A possible cause of testicular damage is the ischaemia-reperfusion (I/R) injury attributed to oxygen free radicals. L-carnitine, a vitamin-like antioxidant, plays a pivotal role in the maturation of spermatozoa within the reproductive tract. The aim of the present paper was to determine the protective effect of L-carnitine on testicular I/R-induced injury. Thirty-two male rats were divided into 4 groups (n = 8). Testicular torsion was created by rotating the right testis 720 degrees in a clockwise direction. Group 1: sham-operated control; group 2: ischaemia; group 3: I/R; group 4: ischaemia-L-carnitine treatment-reperfusion group. L-carnitine (500 mg kg(-1), intraperitoneally) was administered before 30 min of detorsion in Group 4. After torsion (5 h) and detorsion (5 h), bilateral orchidectomy was performed. The malondialdehyde (MDA) level was evaluated in testes. Histopathologically, Johnsen's spermatogenesis criteria and mean seminiferous tubule diameter (MSTD) measurements were used. Testicular MDA levels were higher in the torsion group compared to the sham-control group (p < 0.05). Detorsion (reperfusion) caused a further increase in MDA levels (p < 0.05). Pretreatment with L-carnitine prevented a further increase in MDA levels (p < 0.05). Histologically, torsion caused some separation among germinal cells in the seminiferous tubules, which became much more prominent in the I/R group but was attenuated with L-carnitine pretreatment. In conclusion, L-carnitine pretreatment may have a protective effect in experimental testicular torsion-detorsion model in rats by its well-known antioxidant potential.
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PMID:Protective effect of L-carnitine on testicular ischaemia-reperfusion injury in rats. 1688 24

Several studies have shown a decline in human semen quality and increased risks of male subfertility. This paper provides an overview of the mechanisms of pesticide-induced reproductive toxicity and the effects on male fertility since exposure to pesticides may be one of the causes of these disorders. Pesticides may directly damage spermatozoa, alter Sertoli cell or Leydig cell function, or disrupt the endocrine function in any stage of hormonal regulation (hormone synthesis, release, storage, transport, and clearance; receptor recognition and binding; thyroid function; and the central nervous system). These mechanisms are described with respect to the effects of pesticide exposure in vitro and in vivo. In epidemiologic studies, effects on sperm quality and time to pregnancy are reviewed. Clear effects on male fertility have been demonstrated for some pesticides [eg, dibromochloropropane, ethylene dibromide]. But results from more recent studies are inconsistent, and no uniform conclusion can be drawn about the effects of pesticides on male reproduction.
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PMID:Influence of pesticides on male fertility. 1735 61

Male patients with diabetes type I and type II present more frequently with subfertility. On a subcellular level, increased apoptosis signalling and the rate of DNA fragmentation have an impact on sperm fertilizing capacity. The aim of this study was to evaluate apoptosis signalling and the role of DNA fragmentation in sperm of patients with diabetes type I and type II to gain further insight into the pathophysiology of diabetes-related subfertility in men. Semen specimens collected from 18 healthy fertile donors and 27 donors with diabetes type I (n=13) or type II (n=14) were prepared via density gradient centrifugation. High- and low-density sperm subpopulations were assessed for apoptosis markers (disrupted transmembrane mitochondrial potential, activated caspase 3) and reactive oxygen species, as well as DNA fragmentation, by flow cytometry. The results show that ejaculates of diabetic men contain significantly (P<0.05) higher concentrations of spermatozoa with disrupted transmembrane mitochondrial potential, activated caspase 3, reactive oxygen species and fragmented DNA when compared with healthy fertile donors. The effect is more pronounced in men with diabetes type II. All measured parameters were inversely correlated with the sperm fertilizing potential, indicating a possible mechanism of subfertility in diabetic men. Diabetes mellitus can affect male fertility. Earlier studies have proved reduced sperm motility and lower DNA integrity in germ cells of diabetic patients. It was postulated that higher levels of oxidative stress may contribute to this findings. However, until now the pathophysiology of diabetes-related male subfertility is not fully understood. Our study showed for the first time that apoptosis signalling, measured by disrupted transmembrane mitochondrial potential and activated caspase 3, is significantly increased in sperm from males with diabetes type-I and type-II. Particularly, a disrupted transmembrane mitochondrial potential contributes to the reduced sperm motility. Together with the increased presence of intracellular reactive oxygen species and higher levels of sperm DNA fragmentation, several subcellular factors are now available to explain subfertility in diabetic males.
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PMID:Sperm apoptosis signalling in diabetic men. 2279 31


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