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Previous independent studies have indicated that abnormally low parameters of sperm DNA integrity and sperm membrane integrity correlate to reduced fertility due in part to implantation disorders. The purpose of our study was to evaluate the relationship between sperm plasma membrane functional integrity assessed by the hypo-osmotic swelling test (HOST) and sperm DNA integriy test assesed by DNA fragmentation index (DFI). Semen samples from 102 random patients were evaluated in terms of standard semen parameters and assessed by DFI and HOST. Both tests showed a significant correlation to standard semen parameters (p < .05). In addition, patients with abnormal HOST results had a higher likehood of a subnormal or abnormal DFI result (p < .001). Our results suggest that a common sublethal insult may manifest as abnormalities in both the nucleus and the plasma membrane that act at the implantation and/or subsequent levels of development rather than at the fertilization stage.  相似文献   

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The goal of total phallic reconstruction in the genetic male is the creation of a sensate and cosmetically acceptable phallus with an incorporated neo-urethra that allows the patient to void while standing, engage in penetrative sexual intercourse with confidence and ejaculate in the vagina.  相似文献   

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Background and ObjectiveConventional semen analysis (SA) remains an essential tool in the initial male fertility evaluation and subsequent follow-up. However, it neither provides information about the functional status of spermatozoa nor addresses disorders such as idiopathic or unexplained infertility (UI). Recently, assessment of sperm DNA fragmentation (SDF) has been proposed as an extended sperm test that may help overcome these inherent limitations of basic SA. In this review, we aim to: (I) discuss the pathophysiological aspects of SDF, including natural repair mechanisms, causes, and impact on reproductive outcomes; (II) explain different assessment tools of SDF, and describe potential therapeutic options to manage infertile men with high SDF; and (III) analyse the strengths, weaknesses, opportunities and threats (SWOT) of current research on the topic.MethodsThis review was constructed from original studies, systematic reviews and meta-analyses that were published over the years up until August 2021, related to the various aspects of SDF.Key Content and FindingsDifferent mechanisms lead to high SDF, including defective chromatin packaging, apoptosis, and seminal oxidative stress. The relevance of sperm DNA integrity to male fertility/infertility has been supported by the frequent observation of high levels of SDF in infertile men, and in association with risk factors for infertility. Additionally, high SDF levels have been inversely correlated with the outcomes of natural pregnancy and assisted reproduction. Terminal deoxynucleotidyl transferase dUTP nick end labelling, sperm chromatin structure assay, sperm chromatin dispersion, and Comet assay are four commonly used assays for measurement of SDF. Addressing lifestyle risks and underlying conditions, antioxidants, hormonal therapy, and advanced sperm selection techniques have all been proposed as potential therapeutic options to lower SDF.ConclusionsThe sum of literature provides evidence of detrimental effects of high SDF on both natural and assisted fertility outcomes. Standardization of the techniques used for assessment of SDF and their incorporation into the work up of infertile couples may have significant implications on the future management of a selected category of infertile men with high SDF.  相似文献   

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The human Y-chromosome contains genetic material responsible for normal testis development and spermatogenesis. The long arm (Yq) of the Y-chromosome has been found to be susceptible to self-recombination during spermatogenesis predisposing this area to deletions. The incidence of these deletions is estimated to be 1/4,000 in the general population but has been found to be much higher in infertile men. Currently, Y-microdeletions are the second most commonly identified genetic cause of male infertility after Klinefelter syndrome. This has led to testing for these deletions becoming standard practice in men with azoospermia and severe oligospermia. There are three commonly identified Y-microdeletions in infertile males, termed azoospermia factor (AZF) microdeletions AZFa, AZFb and AZFc. With increased understanding and investigation of this genetic basis for infertility a more comprehensive understanding of these deletions has evolved, with several other deletion subtypes being identified. Understanding the genetic basis and pathology behind these Y-microdeletions is essential for any clinician involved in reproductive medicine. In this review we discuss the genetic basis of Y-microdeletions, the various subtypes of deletions, and current technologies available for testing. Our understanding of this issue is evolving in many areas, and in this review we highlight future testing opportunities that may allow us to stratify men with Y-microdeletion associated infertility more accurately  相似文献   

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无精子症或严重少精子症男性(5×10 6/ml)在接受治疗之前应通过遗传学检测确定其不育的真正原因。正确区分梗阻性无精子症(obstructive azoospermia,OA)与非梗阻性无精子症(non-obstructive azoospermia,NOA)至关重要,因为相比于NOA(睾丸体积小、质地柔软、FSH水平升高),OA(正常的睾丸功能、睾丸体积以及FSH水平)的遗传学检测有所不同。在NOA患者人群中,病史回顾、体格检查和实验室检测对于遗传学检测方法的选择是必须的,尤其针对原发性睾丸衰竭或先天性低促性腺激素型性腺功能低下症的NOA患者。遗传学检测包括由于先天性输精管缺如所致OA的囊性纤维化跨膜传导调节因子的检测,和针对严重少精子症或NOA患者的染色体核型分析、Y染色体微缺失等其他特殊检测方法。这些遗传学检测能够帮助判定哪些患者适合药物和/或手术治疗。最新的遗传学分析技术将有助于男性不育的诊断和掌控。  相似文献   

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Chromatin structure in globozoospermia: a case report   总被引:6,自引:0,他引:6  
Sperm nuclear abnormalities in patients with globozoospermia have not been well characterized and may lead to the high rates of fertilization failure and embryo loss reported in patients with this form of teratozoospermia. This study used transmission electron microscopy (TEM), the sperm chromatin structure assay (SCSA), and single cell gel eletrophoresis assay (COMET) to assess if globozoospermia is associated with sperm chromatin structure abnormalities, DNA fragmentation, or both. The flow cytometric SCSA measures abnormal chromatin structure based on the susceptibility of sperm nuclear DNA to acid-induced denaturation in situ. COMET measures DNA fragmentation in individual sperm nuclei based upon gel electrophoretic patterns. Although sperm concentration (113 million/mL) and motility (66%) were normal in the patient, there was complete acrosome deficiency. TEM and SCSA data confirmed light microscopic examination that showed that sperm populations included a mixture of round and elongated sperm heads. Even though 100% of sperm had abnormal head morphology, only 13% demonstrated DNA denaturation (COMPalpha(t)), which is below our threshold of 15% COMPalpha(t), and consistent with high-fertility patients. Of interest, 13% of the sperm were also positive in the COMET assay, supporting our previous observations that SCSA-positive cells are also positive for DNA fragmentation. It was unexpected but of great interest that a human sperm population with 100% sperm morphology abnormalities had a chromatin integrity at the molecular level that is equivalent to sperm populations shown in previous studies to be highly fertile. These data are the first reported using SCSA and COMET assays to evaluate a patient with globozoospermia and support previous reports that intracytoplasmic sperm injection of globozoospermia may result in fertility/pregnancy. Lower success rates seen in some patients may be due to unrelated factors.  相似文献   

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Prope tolerance: a step in the search for tolerance in the clinic   总被引:3,自引:0,他引:3  
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OBJECT: The authors of previous studies based on diffusion tensor imaging have indicated that there are two types of peritumoral edema-namely, edema with preserved structural integrity of the glial matrix and edema with compromised glial matrix. The authors of this study hypothesized that functionality of the glutamate (Glu)-glutamine shuttle, a vital neuron-glia interaction, may be differentially affected by peritumoral edema. They tested this hypothesis using proton magnetic resonance (MR) spectroscopy on a 3.0-tesla system that is capable of quantifying Glu without need of editing. METHODS: Twenty-three patients, each with a single brain tumor mass and peritumoral edema (nine high-grade gliomas, eight metastatic brain tumors, and six meningiomas), and nine healthy individuals participated in this study. Single-voxel proton MR imaging targeting the region of peritumoral edema was performed using a 3.0-tesla system. Glutamate levels in the peritumoral edema of nonglial tumors was significantly elevated (p < 0.01) compared with edema associated with glial tumors or normal white matter. The finding confirmed that peritumoral edema in nonglial tumors is distinct from that of glial tumors, as previously indicated in diffusion tensor imaging studies. The authors hypothesized that the former condition represents a compensatory increase in activities of the Glu-glutamine shuttle brought about by simple expansion of the extracellular space due to edema. CONCLUSIONS: The assessment of Glu concentrations in peritumoral edema using 3.0-tesla proton MR spectroscopy may be developed into an objective index of the structural integrity of the glial matrix.  相似文献   

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Concern has arisen over human exposures to radio frequency electromagnetic radiation (RFEMR), including a recent report indicating that regular mobile phone use can negatively impact upon human semen quality. These effects would be particularly serious if the biological effects of RFEMR included the induction of DNA damage in male germ cells. In this study, mice were exposed to 900 MHz RFEMR at a specific absorption rate of approximately 90 mW/kg inside a waveguide for 7 days at 12 h per day. Following exposure, DNA damage to caudal epididymal spermatozoa was assessed by quantitative PCR (QPCR) as well as alkaline and pulsed-field gel electrophoresis. The treated mice were overtly normal and all assessment criteria, including sperm number, morphology and vitality were not significantly affected. Gel electrophoresis revealed no gross evidence of increased single- or double-DNA strand breakage in spermatozoa taken from treated animals. However, a detailed analysis of DNA integrity using QPCR revealed statistically significant damage to both the mitochondrial genome (p < 0.05) and the nuclear beta-globin locus (p < 0.01). This study suggests that while RFEMR does not have a dramatic impact on male germ cell development, a significant genotoxic effect on epididymal spermatozoa is evident and deserves further investigation.  相似文献   

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The impact on outcomes resulting from crystalloids used with hemostatic close ratio resuscitation (HCRR) in intraoperative hemorrhage (IOH) has not been analyzed. We hypothesize a survival advantage in patients with IOH managed with a low-volume resuscitation (LVR) protocol during HCRR. A 4-year case-control study was conducted to determine the impact on mortality of LVR versus conventional resuscitation efforts (CRE) during HCRR. A total of 45 patients managed with a HCRR + LVR protocol (combination Hextend? and 3% hypertonic saline) and 55 historical cohorts managed with HCRR + CRE (lactated Ringer's) were included. Patient demographics, number of intraoperative units of packed red blood cells (PRBCs) and fresh-frozen plasma (FFP) received, and FFP:PRBC ratio were similar between groups. The mean intraoperative fluid volume was 0.76 L in the HCRR + LVR group versus 4.7 L in the HCRR + CRE group (P = 0.003). In a linear regression model HCRR + LVR versus HCRR + CRE, mean trauma intensive care unit length of stay was 6 versus 11 days (P = 0.009); 30-day overall mortality was 11.1 versus 32.7 per cent (P = 0.009); perioperative mortality was 2.2 to 10.9 per cent (P = 0.13); and intensive care unit mortality 8.8 to 21.8 per cent (P = 0.07). LVR protocol conveyed a survival benefit to patients undergoing HCRR (odds ratio for mortality, 0.07 [95% confidence interval 0.07-0.54]). This is the first civilian study to analyze the impact of LVR in patients managed with HCRR during IOH. Patients with IOH managed with HCRR and a predefined LVR protocol with Hextend? and 3 per cent hypertonic saline had an overall survival advantage and shorter trauma intensive care unit length of stay. LVR can be an effective alternative to CRE when used in combination with HCRR in patients with IOH.  相似文献   

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M Jochum  W Pabst  W B Schill 《Andrologia》1986,18(4):413-419
Elastase, a specific inflammatory parameter of polymorphonuclear (PMN) granulocytes, was quantified with a sensitive enzyme immunoassay in the ejaculates of 188 patients consulting the andrological outpatient service. Correlations of the elastase concentrations to other parameters used up to now for the diagnosis of silent male genital tract inflammation were statistically evaluated by the CHI2-test. A correlation was found neither to the percentage of morphologically intact spermatozoa in the differential spermiocytogram and the total number of spermatozoa nor to the pH-value and viscosity of the ejaculate. However, release of elastase into the ejaculates was clearly associated with the occurrence of bacteria in native and stained smears or with the numbers of round cells present. Moreover, leukocyte counts in stained smears as well as an inflammation coefficient were highly significantly correlated to elastase concentrations. Obviously, quantification of granulocyte elastase in seminal plasma enables a rapid diagnosis of silent male genital tract inflammation, since even a single determination gives a reliable criterion and sequential determinations may allow the control of the course of the disease during therapy.  相似文献   

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Sex reversal syndrome is a kind of human genetic disease about gender dysplasia, which is characterised by inconsistency between gonadal sexuality and chromosome sexuality; the incidence rate was about 1 : 20 000–100 000. The clinical manifestations, hormonal levels and cytogenetic findings in a patient of 46, XX male sex reversal syndrome retrospectively were analysed and related published reports were reviewed. The DNA fragments of sex-determining region Y (SRY) gene from the patient was found by polymerase chain reaction, but the fluorescent in situ hybridisation analysis revealed that the SRY translocated from Y to X chromosome. We concluded that the Y chromosomal SRY gene is required for the regulation of male sex determination. The detection of SRY is important for the clinical diagnosis of sex reversal syndrome. Translocation of SRY to X chromosome or other autosomes would be one of the key factors that induced XX male SRS.  相似文献   

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As a result of fatigue, bone sustains microdamage, which is then repaired by bone-remodeling processes. How osteoclastic activity is targeted at the removal of microdamaged regions of bone matrix is unknown. In the current studies, we tested the hypothesis that changes in osteocyte integrity, through the initiation of regulated cell death (apoptosis), are associated with fatigue-related microdamage and bone resorption. Ulnae of adult rats were fatigue-loaded to produce a known degree of matrix damage. Osteocyte integrity was then assessed histomorphometrically from terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-nick end labeling (TUNEL)-stained sections to detect cells undergoing DNA fragmentation associated with apoptosis; toluidine blue-stained sections were used for secondary morphological confirmation. Ten days after loading, large numbers of TUNEL-positive osteocytes were found in bone surrounding microcracks and in bone surrounding intracortical resorption spaces (approximately 300% increases over controls, p < 0.005). TUNEL labeling in loaded ulnae at sites distant from microcracks or resorption foci did not differ from that in control bone. Osteocytes in toluidine blue-stained sections showed equivalent trends to TUNEL-stained sections, with significant increases in pyknotic nuclei and empty lacunae associated with microcracks and intracortical resorption spaces. TUNEL-positive osteocytes were observed around bone microdamage by 1 day after loading (p < 0.01 relative to baseline), and their number remained elevated throughout the entire experimental period. Increases in empty lacunae and decreases in normal osteocyte numbers were observed over time as well. These studies show that (1) osteocyte apoptosis is induced by bone fatigue, (2) this apoptosis is localized to regions of bone that contain microcracks, and (3) osteoclastic resorption after fatigue also coincides with regions of osteocyte apoptosis. The strong associations between microdamage, osteocyte apoptosis, and subsequent bone remodeling support the hypothesis that osteocyte apoptosis provides a key part of the activation or signaling mechanisms by which osteoclasts target bone for removal after fatigue-induced matrix injury.  相似文献   

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