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Biomedical subjects

C Y Hong

Publications and source records attributed to C Y Hong.

194 records · Page 11Linked to original sources
PubMedDate not supplied

Measurement of testosterone in seminal plasma, saliva and serum by solid-phase enzymeimmunoassay.

When testosterone concentrations in serum, saliva and seminal plasma were measured with a solid-phase enzymeimmunoassay in which antitestosterone antibody was bound to CNBr-Sepharose-4B, we found the ratios of testosterone in saliva and seminal plasma to that in serum were 2.5 +/- 0.2% and 5.19 +/- 0.42%. Testosterone level in saliva could be an index of free serum testosterone. In addition, we found a correlation between sperm motility and testosterone level in seminal plasma when sperm motility was measured with a transmembrane migration method. This enzymeimmunoassay could be applied to clinical studies of testosterone.

Adult↗
PubMedDate not supplied

Evaluation of human sperm motility by means of transmembrane migration method and computer assisted semen analysis: a comparison study.

Comparing motility parameters with a trans-membrane migration method and a Hamilton-Thorn HTM-2000 computer assisted semen analyzer, we found that trans-membrane migration ratio (TMMR) correlated best with critical motility which indicated the fraction of fastest and straightest sperm in a semen sample. We also found that TMMR correlated better with progressive velocity than with track speed. It is concluded that nonprogressive sperm were not included in the estimation of TMMR and the trans-membrane migration method is most suitable for studying drug effect on straight and rapid sperm motility.

Computers↗
PubMedDate not supplied

Human follicular fluid stimulates motility and velocity of washed human sperm in vitro.

Human follicular fluid collected by laparoscopic oocyte pick-up during IVF was studied with a computer-assisted semen analyser to evaluate the effect of hFF on human sperm motility and velocity. Freshly ejaculated human sperm were washed with phosphate buffered saline and mixed with either PBS or hFF. At various incubation periods of time, hFF increased both sperm motility and velocity as compared with control (P less than 0.01). After incubation of sperm with hFF at 37 degrees C and 5% CO2 in air for 0, 1, 3, 6, and 12 h, the amplitude increase of motility were 49%, 77%, 330%, 2020%, and 3340% when individual control motility was considered to be 100%. The amplitude increase of curvilinear velocity were 43%, 51%, 67%, 152%, 278%, respectively. Comparison of the motility and velocity of the sperm treated with hFF between 0 and 12 h, showed that hFF preserved both motility and velocity in vitro (P less than 0.01). The stimulatory effect of hFF was retained after boiling at 100 degrees C for 30 min, or after being filtered through Amicon membrane cones, but it disappeared if the hFF had been pre-treated with chymotrypsin. However, hFF did not stimulate the motility and velocity of unwashed sperm in freshly ejaculated human semen. A non-dialyzable and heat-stable factor(s) with a molecular weight below 50,000 in hFF may improve and maintain the motility and velocity of washed human sperm. Whether this factor could be used to improve pregnancy rate in assisted reproduction awaits further investigation.

Centrifugation↗
PubMedDate not supplied

A motile human sperm head fixation method.

In a solution containing less than 5% seminal fluid, human sperm has a tendency to attach its head on the smooth surface of an object. Based on such a phenomenon, a simple method was developed to fix sperm head on the surface of glass slide. This method was demonstrated by studying caffeine effect on the tail movement of human sperm in phosphate buffered saline. By analysing the images recorded on a videocassette, caffeine, a well known stimulator of human sperm motility, was shown to induce an immediate increase of sperm TBF (tail beat frequency) and the amplitude of TBF increase was found to be larger in sperm with lower basal TBF value. This method can provide a flock of head-fixed motile sperm for a precise sperm tail movement assessment or for other purposes.

Caffeine↗
PubMedDate not supplied

Effect of lipid peroxidation on beating frequency of human sperm tail.

The tail beat frequency (TBF) of sperm was measured with a sperm-head fixation method which was based on the tendency of sperm to attach its head to the surface of a glass slide. Ferrous sulphate, a promotor of lipid peroxidation, inhibited TBF within 5 min of mixing with sperm. This inhibition can be reversed dose-dependently by superoxide dismutase, catalase, glutathione, and albumin. It was concluded that TBF could be a new pharmacological model for studying the effect of lipid peroxidation and antioxidant on sperm motility. Both enzymatic and non-enzymatic antioxidants can be screened with this method.

Catalase↗
PubMedDate not supplied

Human follicular fluid stimulates the motility of washed human sperm.

Human follicular fluid (hFF) was collected by laparoscopic oocyte pickup during IVF to evaluate the effect of hFF on human sperm motility with a transmembrane migration method. Freshly ejaculated human sperm were washed with phosphate buffered saline (PBS) and mixed with either PBS or hFF. Amplitude of motility increases were 38% and 72% in washed fertile sperm and washed asthenozoospermic sperm when individual control motility was considered to be 100%. The stimulatory effect of hFF was lost when preheated at 100 degrees C for 30 minutes. hFF collected from mature follicles stimulated sperm motility better than that collected from intermediate or immature follicles. hFF did not stimulate the motility of unwashed sperm in freshly ejaculated human semen. A heat labile factor(s) in hFF may stimulate the motility of washed human sperm. Whether this factor could be used to improve the success rate of IVF and artificial insemination awaits further investigation.

Female↗
PubMedDate not supplied

Techniques for selection of normal-chromatin sperm preparations.

Various sperm preparation techniques, swim-up and Percoll gradient, and the newly developed Wang's tube system, were evaluated for their ability to recover normal-chromatin sperm. Twenty human semen samples, collected by masturbation, were studied simultaneously with the three methods. Analysis by Acridine orange fluorescence test was performed on all samples. Pretreated semen contains 58 +/- 22% green sperm (fertile/normal). Treatment with Wang's tube system resulted in 99 +/- 1.0% green sperm; Percoll gradient, 78 +/- 11%; and swim-up technique, 72 +/- 15%. It would appear that Wang's tube system yields a high-quality sperm preparation with enough concentration, very active forward progression, and greatly improved sperm morphology, while containing normal-chromatin, double-stranded DNA.

Acridine Orange↗
PubMedDate not supplied

Modification of the Wang tube to improve in vitro semen manipulation.

The Wang tube was modified to improve in vitro semen manipulation, by adding another two racks to the anterior (posterior) wall of the low component of the Wang tube and supplying another four convex lenses symmetrical to those on the bottom wall. The former provides a slanted position leading to a complete real-time sperm separation image and benefiting low-quality sperm preparation when the modified Wang tube is turned on its side. The latter converses the microscope's light better and gives a clearer objective image.

Fertilization in Vitro↗
PubMedDate not supplied

Tail beat frequency of human sperm: evaluated with sperm head fixation method and computer-assisted semen analysis.

Tail beat frequency (TBF) of individual sperm in 15 semen samples was evaluated with a sperm head fixation method (SHFM). Motility parameters of the semen samples were also measured with computer-assisted semen analysis (CASA). The TBF obtained from SHFM correlated best with beat cross-frequency obtained from CASA. The TBF measured soon after sperm head fixation also correlated well with total motility and rapid motility, but not with progress motility and critical motility measured with CASA. SHFM is a simple method for the study of tail beat frequency and the TBF of individual sperm is closely related to the overall motility in a semen sample.

Computers↗
PubMedDate not supplied

Magnolol protects human sperm motility against lipid peroxidation: a sperm head fixation method.

It was previously reported that magnolol, isolated from the Chinese medicinal herb Magnolia officinalis, had a potent inhibitory activity on lipid peroxidation. Since sperm motility could be suppressed by lipid peroxidation, this study examines the protective effect of magnolol on lipid peroxidation-suppressed sperm motility. FeSO4 was used to induced lipid peroxidation and sperm motility was expressed as tail beat frequency (TBF) measured with a sperm head fixation method. Magnolol at 10(-9) to 10(-7) M significantly reversed the FeSO4-suppressed TBF. Magnolol significantly inhibited the generation of malondialdehyde (MDA), the end product of lipid peroxidation, in sperm. Magnolol protected sperm motility by inhibiting lipid peroxidation in sperm.

Biphenyl Compounds↗
PubMedDate not supplied

The effect of curing light intensity on the cytotoxicity of a dentin-bonding agent.

Various dentin-bonding agents (DBAs) have been widely used to improve the bonding strength of dental resins and to prevent microleakage at the resin-dentin interface, although DBA may exert potentially detrimental effects upon dental pulp. In this study, a DBA (Scotchbond Multi-purpose) cured at different light intensities (100, 200 and 300-mW/cm2) for 10 seconds was extracted with Dulbecco's modified Eagle's medium (DMEM) for 24 hours. Thereafter, pulp cells (1 x 10(4) cells/well) were exposed to DMEM with or without DBA extract for 12 hours, 24 hours and five days. Pulp-cell cytotoxicity was measured with a modified 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. No significant cytotoxicity of DBA eluents on pulp cells was found for the 12-hour exposure group. Following 24-hour exposure of cells to DBA cured at 100-mW/cm2, pulp cells became rounder, more retracted and lost some cellular processes as compared to controls. Five-day exposure of pulp cells to DBA extract cured by light at levels of 100, 200 and 300 mW/cm2, respectively, led to a growth retardation of 26%, 48% and 70% as analyzed by the inhibition of mitochondrial dehydrogenase activity. These results indicate that DBA may exert some cytotoxic effects upon dental pulp, especially when DBA-curing is insufficiently complete, as may occur at a low light intensity.

Cell Division↗
PubMedDate not supplied

Fluorescence supravital stain of human sperm: correlation with sperm motility measured by a transmembrane migration method.

We developed a supravital stain of human sperm with fluorescent dyes. Either Hoechst 33,258 or fluorescein isothiocyanate could be used, the former stained sperm head while the later stained the whole sperm. Sperm vitality assessed with any of these two fluorescent dyes correlated well with that determined by eosin-nigrosin counterstain. When sperm vitality was compared with sperm motility measured with a transmembrane migration method, we found that many vital sperm were immotile because sperm vitality was higher than sperm motility in tested samples.

Bisbenzimidazole↗
PubMedDate not supplied

Hemodynamic effects of acute tetrandrine and terlipressin administration on portal hypertensive rats.

The purpose of this study was to investigate the therapeutic effects of tetrandrine and terlipressin, alone or in combination, on anesthetized portal hypertensive rats. Portal hypertension was induced by partial portal vein ligation in Sprague-Dawley rats. Each portal hypertensive rat received one of three regimens: vehicle plus terlipressin, tetrandrine (.50 mg.kg-1.min-1) [corrected] plus terlipressin, or tetrandrine (.75 mg.kg-1.min-1) [corrected] plus terlipressin. Terlipressin dosage was 0.025 mg.kg-1.min-1 [corrected] infused for 3 min. Infusion of vehicle followed by terlipressin induced significant reduction of portal venous pressure (PVP, -24.3 +/- 1.5%) and prominent elevation of mean arterial pressure (MAP, 73.3 +/- 4.6%) as well as total peripheral resistance (TPR, 133 +/- 8%) from baseline, and there was a cardiodepressant response (cardiac index, CI, -30.6 +/- 3.8%; heart rate, HR, -10.4 +/- 2.1%). Infusion of tetrandrine (.50 mg.kg-1.min-1) [corrected] induced significant reduction of PVP (-7.2 +/- 0.9%), MAP (-12.5 +/- 1.6%), and TPR (-14.3 +/- 4.2%) from baseline. Infusions of tetrandrine followed by terlipressin induced significant reduction of PVP (-14.2 +/- 2.4%) but an increase in MAP (22.6 +/- 2.7%) and TPR (71.1 +/- 10.5%). Infusion of tetrandrine (.75 mg.kg-1.min-1) [corrected] induced significant reduction of PVP (-9.9 +/- 0.8%). MAP (-19.2 +/- 2.1%), and TPR (-24.1 +/- 2.1%) from baseline. Infusions of tetrandrine followed by terlipressin induced significant reduction of PVP (-14.0 +/- 1.1%) but an increase in MAP (14.0 +/- 2.7%) and TPR (75.2 +/- 5.2%). Compared with vehicle followed by terlipressin, tetrandrine significantly attenuated systemic pressor (MAP and TPR elevation), cardiodepressant (CI reduction) as well as portal hypotensive (PVP reduction) effects of terlipressin. Our results suggest that tetrandrine and terlipressin, alone or in combination, induced portal hypotensive effects in portal hypertensive rats. Combined tetrandrine and terlipressin administration ameliorated systemic pressor and cardiodepressant effects of terlipressin, but it also attenuated the latter's portal hypotensive effects.

Alkaloids↗