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H.-R. Xu

Bio: H.-R. Xu is an academic researcher from Nanjing Normal University. The author has contributed to research in topics: Sperm. The author has an hindex of 2, co-authored 2 publications receiving 25 citations.
Topics: Sperm

Papers
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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

Journal ArticleDOI
TL;DR: In conclusion, centrifugal velocity and abstinence time should be standardized in the alpha-glucosidase determination and Frozen seminal plasma may serve as the sample for quality control among clinical laboratories.
Abstract: We attempted to provide an instruction for the standardization of alpha-glucosidase level determination and quality controls within the same laboratory and among different laboratories. Each of 51 semen samples was divided into two aliquots, centrifuging at 1000 g for 10 min or 3000 g for 15 min. The alpha-glucosidase level and sperm concentration of each sample were assayed. The alpha-glucosidase level in seminal plasma obtained at 3000 g for 15 min centrifugation was significantly lower than that at 1000 g for 10 min (p = 0.001). An additional 6 samples of seminal plasma with or without phenylmethylsulfonyl fluoride (PMSF), obtained at 3000 g for 15 min centrifugation, were frozen for 20 days, and each of 6 samples was determined for their alpha-glucosidase levels after thawing every other day. There was no significant difference between alpha-glucosidase levels in seminal plasma regardless of the presence of PMSF. The alpha-glucosidase level increased with the length of abstinence period. In conclusion...

11 citations


Cited by
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Journal ArticleDOI
TL;DR: The systematic review's research questions relate to the caries-reducing benefits and associated potential health risks of providing fluoride systemically and the use of topical fluoride agents and the hierarchy of study types considered most relevant for answering each of the clinical questions defined in this review was chosen.
Abstract: The systematic review was commissioned by the Australian National Health and Medical Research Council (NHMRC) to evaluate the scientific literature relating to the health effects of fluoride and fluoridation. The systematic review's research questions relate to the caries-reducing benefits and associated potential health risks of providing fluoride systemically (via addition to water, milk and salt) and the use of topical fluoride agents, such as toothpaste, gel, varnish and mouthrinse. Although the review summarises the recent evidence, it does not constitute health policy or clinical practice recommendations. A literature search was undertaken using the Medline and Embase databases (via www.embase.com ). In addition, the Cochrane Systematic Review and Clinical Trial databases were searched to help identify additional systematic reviews and original studies. Because of the availability of recent systematic reviews, searches were limited to publications from 1996 onwards . The search was conducted in December 2006 and limited to English-language publications. Based on types of intervention (individual or population) and the outcomes assessed (efficacy or safety), the hierarchy of study types considered most relevant for answering each of the clinical questions defined in this review was chosen (Table 1). The levels of evidence used by NHMRC for intervention and aetiological studies are summarised in Table 2. Screening of eligible studies was conducted by three reviewers. Data were extracted for all of the included systematic reviews and individual studies using standardised data-extraction forms. This included information about the study design, NHMRC level of evidence, population, intervention, comparator, outcome definitions and results. Information relating to potential biases and study quality were also extracted. Where appropriate, study results were pooled using standard meta-analysis techniques. In total, 5418 nonduplicate citations were identified. After applying the inclusion and exclusion criteria, 408 citations were considered potentially eligible for inclusion in the review. After the review of the full papers of potentially eligible articles, 77 citations were included in the review. The summary of findings was presented in the context of the research questions (Table 3). Fluoridation of drinking water remains the most effective and socially equitable means of achieving community-wide exposure to the caries prevention effects of fluoride. It is recommended (see also www.nhmrc.gov.au/news/media/rel07/_files/fluoride_flyer.pdf ) that water be fluoridated in the target range of 0.6–1.1 mg/l, depending on the climate, to balance reduction of dental caries and occurrence of dental fluorosis.n particular with reference to care in hospital for those following stroke.

226 citations

Journal ArticleDOI
TL;DR: The literature is revised, describing fluorescent probes that have been used for analysing spermatozoa by flow cytometry, regarding viability, acrosomal status, capacitation, mitochondrial status, apoptotic markers, oxidative stress markers, DNA damage, sperm counting and sperm sizing.
Abstract: CONTENTS: Flow cytometry has become an important technique in sperm evaluation and is increasingly used both for routine assessment and for research in veterinary science. We have revised the liter ...

159 citations

Journal ArticleDOI
TL;DR: The present and future capabilities of flow cytometry for the diagnostics of potential fertility and for the development of current reproductive technologies such as sperm freezing, sperm selection and sperm sorting are critically evaluated.
Abstract: Flow cytometry is now a recognized methodology within animal spermatology, and has moved from being a research tool to become routine in the assessment of animal semen destined to breeding. The availability of 'bench-top' flow cytometers and of newer and versatile markers for cell structure and function had allowed the instrumentation to measure more sperm parameters, from viability to reactiveness when exposed to exogenous stimuli, and to increase our capabilities to sort spermatozoa for potential fertilizing capacity, or chromosomal sex. The present review summarizes the state of the art regarding flow cytometry applied to animal andrology, albeit keeping an open comparative intent. It critically evaluates the present and future capabilities of flow cytometry for the diagnostics of potential fertility and for the development of current reproductive technologies such as sperm freezing, sperm selection and sperm sorting. The flow cytometry methods will probably further revolutionize our understanding of the sperm physiology and their functionality, and will undoubtedly extend its application in isolating many uncharacterized features of spermatozoa. However, continuous follow-up of the methods is a necessity owing to technical developments and the complexity of mapping spermatozoa.

143 citations

MonographDOI
01 Apr 2010
TL;DR: A Practical Guide to Basic Laboratory Andrology - Libros de Medicina - Fertilidad y embarazo - 39,42
Abstract: This practical, extensively illustrated handbook covers the procedures that are undertaken in andrology and ART laboratories to analyse and assess male-factor infertility, and to prepare spermatozoa for use in assisted conception therapy. The content is presented as brief, authoritative overviews of the relevant biological background for each area, plus detailed, step-by-step descriptions of the relevant analytical procedures. Each technical section includes pertinent quality control considerations, as well as the optimum presentation of results. In addition to the comprehensive 'basic' semen analysis, incorporating careful analysis of sperm morphology, the handbook provides established techniques for the use of computer-aided sperm analysis and sperm functional assessment. Throughout the handbook the interpretation of laboratory results in the clinical context is highlighted, and safe laboratory practice is emphasized. It is an invaluable resource to all scientists and technicians who perform diagnostic testing for male-factor infertility.

99 citations

Journal ArticleDOI
TL;DR: It is demonstrated that there is a systematic overestimation in the proportion of unstained (viable) cells detected by flow cytometry in cases where the non-sperm particles are not excluded from analysis by additional identification other than light-scatter characteristics.

55 citations