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Yu-Feng Huang

Bio: Yu-Feng Huang is an academic researcher from Nanjing University. The author has contributed to research in topics: Male infertility & Sperm. The author has an hindex of 10, co-authored 34 publications receiving 293 citations.

Papers
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Journal ArticleDOI
TL;DR: This review focuses on the concept of CASA, the development course of CAS a technology, the clinical application of CASa systems and the factors influencing the accuracies of results, such as frame rate, sperm counting chambers affiliated to the CASA system, algorithms and sperm concentration.
Abstract: Computer-aided sperm analysis (CASA) system has been accepted and used commonly as a routine semen analysis instrument in hospital clinical laboratories worldwide. However, technicians in clinical laboratories have little informed knowledge about the principles of CASA system and the sources of analysis errors. In this review, we focus on the concept of CASA, the development course of CASA technology, the clinical application of CASA systems and the factors influencing the accuracies of results, such as frame rate, sperm counting chambers affiliated to the CASA system, algorithms and sperm concentration. These factors and lack of internal quality control may result in huge errors of the CASA between systems and laboratories. It is therefore necessary to perform the standardisation and quality control for CASA.

98 citations

Journal ArticleDOI
TL;DR: The results suggested that detection of MDA concentrations in seminal plasma by HPLC has an indicative value on the diagnosis of male infertility induced by overproduction of reactive oxygen species in male reproductive system.
Abstract: For the purpose to evaluate the significance of lipid peroxidative products on male infertility, the levels of malondialdehyde (MDA), which is one of the final products of lipid peroxidation in seminal plasma, were determined. Ninety-three male infertile patients were divided into obstructive azoospermic group (12 cases), non-obstructive azoospermic group (15 cases), oligozoospermic group (21 cases), asthenozoospermic group (19 cases), oligoasthenozoospermic group (16 cases) and oligoasthenoteratozoospermic group (10 cases). Eighteen fertile males were included in the control group. MDA concentrations of seminal plasma in the fertile and infertile men were detected by high-performance liquid chromatography (HPLC). The results showed that the concentration of MDA in seminal plasma differed significantly between the control group and all the infertile groups (P < 0.01) except the obstructive azoospermic group, between the oligoasthenozoospermic group and the oligozoospermic and asthenozoospermic groups (P <...

31 citations

Journal Article
TL;DR: ROS can damage the mitochondrial function of sperm by affecting MMP of spermatozoa and the activity of SDH, but melatonin can protect sperm mitochondria from the damage induced by ROS through its effective antioxidative potential.
Abstract: Objective To study the damage of mitochondrial function of sperm induced by reactive oxygen species (ROS), and the protection of melatonin (MLT) against the damage. Methods Spermatozoa of normal physiological function selected from semen samples by Percoll gradient centrifugation technique were used as normal sperm models in the present study. Reactive oxygen species were generated by hypoxanthine xanthine oxidase system, and in the presence (or absence) of MLT (6 mmol/L), incubated with normal sperm models for 30 and 60 minutes. After incubation, the activity of succinate dehydrogenase (SDH) in mitochondria of spermatozoa was assessed by histochemical method, and spermatozoa were labeled with specific fluorescent probe of Rhodamine 123 to measure mitochondrial membrane potential (MMP) by flow cytometry. Results After normal spermatozoa were incubated with ROS, MMP of spermatozoa significantly decreased, and the activity of SDH almost decreased to zero. However, MLT had effect on reducing the damage of the mitochondrial function of sperm induced by ROS. Conclusion ROS can damage the mitochondrial function of sperm by affecting MMP of spermatozoa and the activity of SDH. MLT can protect sperm mitochondria from the damage induced by ROS through its effective antioxidative potential.

28 citations

Journal ArticleDOI
TL;DR: Factor settings and evaluation algorithms could significantly affect the results obtained from these two branded CASA systems and great attention should also be paid to the quality control in semen analysis with CASA.
Abstract: Summary The study evaluated the comparability of two branded computer-aided sperm analysis (CASA) systems commonly used in andrology laboratories in China. The same semen sample was analysed using two branded CASA systems (WLJY-9000 and CFT-9200) by one well-trained technician. Results of semen analysis obtained from two branded CASA systems were then compared. The accuracy of counting results of CASA systems was evaluated using latex bead solutions with known concentrations of (35 ± 5) × 106 ml−1 and (18 ± 2.5) × 106 ml−1. There were significant differences in all parameters (P < 0.01) except for LIN and WOB. The counting results of CFT-9200 were close to the standard solutions [(38.86 ± 3.79) × 106 ml−1 and (19.03 ± 1.99) × 106 ml−1], while those of WLJY-9000 were underestimated [(28.53 ± 2.06) × 106 ml−1 and (14.62 ± 0.95) × 106 ml−1]. But the coefficient of variation of WLJY-9000 was lower than that of CFT-9200 (7.22%, 6.50% vs. 9.82%, 10.46%). It is concluded that factors such as parameter settings and evaluation algorithms could significantly affect the results obtained from these two branded CASA systems. Great attention should also be paid to the quality control in semen analysis with CASA.

26 citations

Journal ArticleDOI
TL;DR: Flow cytometry can result in an overestimation of both bead counting and sperm concentration, suggesting that flow cytometry is an inappropriate method for sperm counting, especially in the case of azoospermia.
Abstract: It has been reported that flow cytometry can be used as a reference procedure to determine sperm concentrations in quality control schemes in andrology laboratories, but there are no convincing quality control data. To understand comprehensively whether flow cytometry can be used to determine sperm concentration, sperm concentrations of 85 human semen samples were detected using three different methods, namely flow cytometry, computer-assisted semen analysis (CASA) and manual counting with a cell-VU chamber. The bead concentrations of both low [(18+/-2.5)x10(6)/mL] and high [(35+/-5)x10(6)/mL] pre-calibrated standard latex bead solutions were also determined with flow cytometry. The results showed that bead concentrations of both low and high pre-calibrated standard latex bead solutions counted five times with flow cytometry were (21.37+/-0.85)x10(6)/mL and (45.95+/-1.76)x10(6)/mL, respectively. Coefficient variances (CVs) and relative errors (REs) were 4%, 15.51% and 3.84%, 31.3% for low and high latex bead solutions, respectively. The overall correlation between values measured with flow cytometry and values measured with the cell-VU chamber and the CASA system was significant. However, flow cytometry overestimated the sperm concentration by 109% compared to the results with the cell-VU chamber. Moreover, for the azoospermic samples analysed, the sperm concentration was estimated at 0.12 (range from 0.04 to 0.24)x10(6)/mL. In conclusion, the data demonstrated that flow cytometry can result in an overestimation of both bead counting and sperm concentration, suggesting that flow cytometry is an inappropriate method for sperm counting, especially in the case of azoospermia.

18 citations


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Journal ArticleDOI
TL;DR: This review will provide an overview of oxidative biochemistry related to sperm health and identify which men are most at risk of oxidative infertility, and outline methods available for diagnosing oxidative stress and the various treatments available.
Abstract: Oxidative stress occurs when the production of potentially destructive reactive oxygen species (ROS) exceeds the bodies own natural antioxidant defenses, resulting in cellular damage. Oxidative stress is a common pathology seen in approximately half of all infertile men. ROS, defined as including oxygen ions, free radicals and peroxides are generated by sperm and seminal leukocytes within semen and produce infertility by two key mechanisms. First, they damage the sperm membrane, decreasing sperm motility and its ability to fuse with the oocyte. Second, ROS can alter the sperm DNA, resulting in the passage of defective paternal DNA on to the conceptus. This review will provide an overview of oxidative biochemistry related to sperm health and will identify which men are most at risk of oxidative infertility. Finally, the review will outline methods available for diagnosing oxidative stress and the various treatments available.

1,231 citations

Journal ArticleDOI
TL;DR: Adequately powered, placebo-controlled comprehensive clinical trials are now required to establish a clear role for antioxidants in the prevention of oxidative stress in the male germ line, such that the clinical utility of this form of therapy becomes established once and for all.
Abstract: Oxidative stress in the male germ line is thought to affect male fertility and impact upon normal embryonic development. Accordingly, fertility specialists are actively exploring the diagnosis of such stress in spermatozoa and evaluating the possible use of antiox- idants to ameliorate this condition. In this review, evidence for the presence of oxidative stress in human spermatozoa, the origins of this phenomenon, its clinical significance in the aetiology of male infertility and recent advances in methods for its diagnosis and treatment are re- examined. Moreover, an extensive review of the results presented in published clinical studies has been conducted to evaluate the overall impact of oral antioxidants on measures of sperm oxidative stress and DNA damage. Administration of antioxidants to infertile men has been assessed in numerous clinical studies with at least 20 reports highlighting its effect on measures of oxidative stress in human spermatozoa. A qualitative but detailed review of the results revealed that 19 of the 20 studies conclusively showed a significant reduction relating to some measure of oxidative stress in these cells. Strong evidence also supports improved motility, particularly in asthenospermic patients. However, of these studies, only 10 reported pregnancy-related outcomes, with 6 reporting positive associations. Adequately powered, placebo-con- trolled comprehensive clinical trials are now required to establish a clear role for antioxidants in the prevention of oxidative stress in the male germ line, such that the clinical utility of this form of therapy becomes established once and for all.

443 citations

Journal ArticleDOI
TL;DR: Current CASA systems provide information important for quality assurance of semen planned for marketing, and for the understanding of the diversity of sperm responses to changes in the microenvironment in research.

348 citations

Journal ArticleDOI
TL;DR: The recognition of vitamin C is associated with a history of an unrelenting search for the cause of the ancient haemorrhagic disease scurvy, and further continuous uninterrupted efforts may open new vistas to understand its significance in disease management.
Abstract: The recognition of vitamin C is associated with a history of an unrelenting search for the cause of the ancient haemorrhagic disease scurvy. Isolated in 1928, vitamin C is essential for the development and maintenance of connective tissues. It plays an important role in bone formation, wound healing and the maintenance of healthy gums. Vitamin C plays an important role in a number of metabolic functions including the activation of the B vitamin, folic acid, the conversion of cholesterol to bile acids and the conversion of the amino acid, tryptophan, to the neurotransmitter, serotonin. It is an antioxidant that protects body from free radical damage. It is used as therapeutic agent in many diseases and disorders. Vitamin C protects the immune system, reduces the severity of allergic reactions and helps to fight off infections. However the significance and beneficial effect of vitamin C in respect to human disease such as cancer, atherosclerosis, diabetes, neurodegenerative disease and metal toxicity however remains equivocal. Thus further continuous uninterrupted efforts may open new vistas to understand its significance in disease management.

344 citations

Journal ArticleDOI
TL;DR: A critical review of the literature describing the role of oxidative stress on decreased sperm function, as well as the roleof antioxidants in the treatment of male factor infertility is presented.
Abstract: Male infertility continues to be a clinical challenge of increasing significance. While male factors such as decreased semen quality are responsible for 25% of all infertility issues, the etiology of suboptimal semen quality is poorly understood. Many physiological, environmental, and genetic factors have been implicated, including oxidative stress. Oxidative stress is induced by reactive oxygen species (ROS), or free radicals, and although ROS are required for critical aspects of sperm function, excessive levels of ROS can negatively impact sperm quality. The origin of ROS generation, and the etiologies of increased ROS in men with suboptimal sperm quality have only recently been elucidated, offering multiple targets for potential therapy. Here, we present a critical review of the literature describing the role of oxidative stress on decreased sperm function, as well as the role of antioxidants in the treatment of male factor infertility.

247 citations