Showing papers by "Christina Wang published in 1989"

Predictive value of sperm morphology and movement characteristics in the outcome of in vitro fertilization of human oocytes.

Abstract: One hundred fourteen semen samples from Chinese males were analyzed for routine semen parameters including the semen volume, sperm count, percentage motility, and percentage normal morphology. Of these 114 samples, 54 also had movement characteristics of seminal and swim-up sperm evaluated by the computer image analyzer system (Cellsoft; Cryo Resources Co., New York). All semen samples were subjected to the swim-up procedure to harvest the motile sperm before inseminations of human oocytes. Fertilization was considered to have occurred when at least one oocyte was observed with two or more pronuclei. Semen samples were classified as infertile (0% fertilization rate;N=32) or fertile (>0% fertilization rate;N=82) before statistical analyses. There was a significant difference (P<0.005) in percentage normal morphology of seminal sperm between the fertile (mean±SE; 67.3±1.2%) and the infertile (59.3±2.2%) samples. The percentage normal morphology of seminal sperm correlated (r=0.3049;P<0.002) with the fertilization rate and this parameter was selected by the multivariate stepwise discriminant analysis as the discriminator capable of predicting the fertilization rate with 57.9% accuracy. Statistical analyses of samples where sperm movement was also evaluated demonstrated that there was significant differences (P<0.01) between the fertile (N=38) and the infertile (N=16) samples in percentage normal morphology of seminal sperm (67.8±1.8% vs 56.2±2.6%) and curvilinear velocity of swim-up sperm (89.2±3.5 vs 68.2±7.2 μm/sec). The fertilization rates correlated with the percentage normal morphology of seminal sperm (r=0.3868;P<0.005) and velocity of swim-up sperm (r=0.3842;P<0.005). Multivariate stepwise discriminant analysis demonstrated that these two sperm parameters in combination were capable of predicting the fertilization rate with 74.1% accuracy. Our results indicate that seminal sperm morphology, coupled with computerassisted image analysis of movement characteristics of swim-up sperm, can help to predict the outcome of in vitro fertilization of human oocytes.

Comparison of the effectiveness of 2-hourly versus 8-hourly subcutaneous injections of a somatostatin analog (SMS 201-995) in the treatment of acromegaly.

Abstract: To determine whether sc injections of a somatostatin analog (SMS 201-995) every 2 h (q2h) is more effective than sc injections every 8 h (q8h) in achieving a constant suppression of GH levels and a more satisfactory clinical response, we studied 10 patients with acromegaly (4 newly diagnosed and 6 previously treated with bromocriptine/pituitary irradiation/transfrontal hypophysectomy). The dose of SMS 201-995 was increased from 300 micrograms/day to a maximum of 600 micrograms/day when the mean serum GH (hourly samples for 12 h) failed to be suppressed to undetectable levels in over 75% of the samples. Five patients received a 200-micrograms sc injection q8h (600 micrograms/day), and the other 5 received sc injections q2h [418 +/- 46 micrograms/day (mean +/- SE); range, 288-504 micrograms/day]. In the group receiving q2h sc SMS 201-995 there was a marked suppression of mean GH from a basal level of 77.3 +/- 24.7 mU/L to less than 5 mU/L in all five subjects. In the group receiving q8h sc SMS 201-995, mean GH was suppressed from a basal level of 82.2 +/- 21.7 to 15.4 +/- 3.3 mU/L after 6 months of therapy, and none of the patients had a mean GH level consistently less than 5 mU/L. Despite the difference in the level of GH suppression, mean serum somatomedin-C levels were decreased promptly in both groups of subjects. Associated with the decrease in somatomedin-C levels there was a marked clinical response in both groups, but improvement in clinical features and decreases in hand volumes and ring size occurred earlier in the group receiving SMS 201-995 q2h. Significant tumor shrinkage (25% to greater than 50% reduction) was observed in two patients receiving q2h injections, while a 25-50% reduction in tumor size was noted in another patient receiving q8h injections. Because of the small doses of SMS 201-995 used side-effects of abdominal discomfort and flatulence were mild and rapidly disappeared. Our results show that increasing the frequency of sc administration of the somatostatin analog from q8h to q2h leads to more marked and consistent suppression of GH levels and more rapid improvement of clinical signs. Increasing the frequency of delivery of SMS 201-995 may be an alternative to increasing the dose in some patients with acromegaly.

Glucocorticoids stimulate plasminogen activator production by rat granulosa cells.

Abstract: We studied the direct effects of glucocorticoids on plasminogen activator (PA) production by rat granulosa cells. PA production was assayed by culturing rat granulosa cells on [125I]fibrin plates and determining the extent of fibrinolysis after addition of the specific substrate plasminogen. In granulosa cells from preantral follicles of immature rats, treatment with FSH caused dose-dependent increases in PA production whereas glucocorticoids by itself was without effect. Increasing concentrations (10-10 to 10-8 M) of both natural and synthetic glucocorticoids potentiated the stimulating effect of FSH on PA production by 120 to 170%. The stimulatory potencies of the natural corticosteroids correlated with the glucocorticoid potencies (cortisol/ corticosterone > aldosterone/11-deoxycorticosterone). In granulosa cells from Graafian follicles of mature rats, glucocorticoids on its own had direct stimulating effect on PA production. The stimulatory action of glucocorticoids on FSH-dependent PA production was ...

Computer‐assisted image analysis of sperm concentration in human semen before and after swim‐up separation: comparison with assessment by haemocytometer

Abstract: Evaluation of male fertility is based predominantly on results from semen analysis and determination of the sperm concentration is one of the main parameters of the analysis. The availability of a fully automated videomicrographic digital image analyser would offer both an objective and rapid method for determination of the sperm concentration. In the present study the sperm concentration in 327 semen samples was determined by haemocytometer according to the World Health Organization guidelines, and also by a computer-assisted digital image analyser system. Results were classified according to the routine procedure (haemocytometer) before statistical analyses. The computerized measurements caused a shift to the right in the frequency distribution of sperm concentration. Sperm concentrations were more often overestimated significantly (P less than 0.001) by the computerized measurements in semen samples with concentrations up to 80.0 x 10(6)/ml. This overestimation seemed to be caused by the presence of particles in seminal plasma that were recognized incorrectly as sperm by the computer program. The computerized digital image analyser gave an average sperm concentration of 2.2 +/- 0.6 x 10(6)/ml (mean +/- SEM) in 17 azoospermic semen samples while the routine procedure did not detect the presence of sperm cells. After removing the seminal plasma by washing and centrifugation with culture medium, and using the swim-up procedure to harvest motile sperm, the computerized measurements showed comparable results with the routine procedure for those sperm preparations (n = 44) with sperm concentrations greater than 5.0 x 10(6)/ml.(ABSTRACT TRUNCATED AT 250 WORDS)

Intrauterine Insemination Is Not Useful in Oligoasthenospermia

Abstract: A prospective randomized study was conducted in 47 couples with infertility due to subnormal semen to compare luteinizing hormone (LH)-timed intrauterine insemination with LH-timed natural intercourse. No pregnancy occurred in 114 cycles of intrauterine insemination with washed sperm. Only one patient conceived during 1 of the 124 natural intercourse cycles. The only complication that occurred after intrauterine insemination was mild abdominal cramp in 3 cycles. The authors conclude that intrauterine insemination is not useful in the management of subfertility due to oligoasthenospermia.

Erythrocyte sodium-potassium pump in thyrotoxic periodic paralysis.

Abstract: To search for a genetic marker in patients with thyrotoxic periodic paralysis (TPP), we studied the erythrocyte sodium-potassium pump activity in 13 patients with TPP; 30 thyrotoxic patients with no history of paralysis (T) and 69 euthyroid controls. In thyrotoxic patients (TPP and T), erythrocyte ouabain binding and ouabain sensitive sodium efflux rate constant were decreased while erythrocyte sodium content was increased. All these changes reverted to normal when the patients became euthyroid. Maximal ouabain binding capacity correlated positively with ouabain sensitive sodium efflux rate constant (r = 0.542; p less than 0.001; n = 155) and negatively with serum thyroxine concentration (r = -0.571; p less than 0.001; n = 60) and erythrocyte sodium content (r = -0.521; p less than 0.001; n = 155). In the thyrotoxic state, maximal ouabain binding capacity was just significantly higher in TPP when compared with T (0.268 +/- 0.014 and 0.234 +/- 0.009 pmol/10(9) cells respectively; p less than 0.05). This difference could not be demonstrated when the patients became euthyroid. Our findings suggest that patients with TPP respond to thyrotoxicosis with a smaller decrement in erythrocyte sodium-potassium ATPase activity than patients without a history of paralysis. However, the difference is too small to represent a useful genetic marker for this disease entity

Long‐term effects of megavoltage radiotherapy in acromegaly

Abstract: The progress of 41 Chinese patients with acromegaly treated with megavoltage radiotherapy was reviewed after a mean follow-up of 4.5 (one-ten) years. Nine received prior surgery. Radiotherapy was delivered by a 3-field technique to a total of 4000-5000 cGy in 25 fractions. By life table analysis successful treatment of growth hormone (GH) hypersecretion, as defined by a mean GH concentration of less than or equal to 10 mu/L, could be expected in 6, 11, 26, 64 and 67% of the patients after one, two, five, eight and ten years respectively. Median intervals before achieving a mean GH level of less than or equal to 10 mu/L were 6.6 and 8.6 years following radiotherapy with the higher (4500-5000 cGy) and lower (4000 cGy) doses respectively, suggesting a tendency towards earlier response following radiotherapy with the higher dose. The prevalence of acquired hypopituitarism in patients followed up for over five years was 40% for gonadotrophins, 30% for TSH and 20% for ACTH deficiency respectively. In the majority of patients, acquired hypopituitarism was not apparent within five years after radiotherapy. No mortality or major side effects were noted following radiotherapy. In 34 patients on long-term bromocriptine treatment, mean GH concentrations were normalised in 26.5% of patients. We conclude that with judicious selection of patients and use of adjunctive medical therapy, megavoltage radiotherapy remains a safe and satisfactory form of treatment for acromegaly especially if expert transphenoidal surgery is not readily available.

Imaging for adrenal tumours

Abstract: Summary Modern medical imaging has transformed the diagnosis and management of adrenal disease. The various types of adrenal tumours bear different aspects of problems in diagnostic imaging. The investigation used must be determined and monitored individually, as directed by the clinical and biochemical findings. CT plays a central role in the localization of the functioning adrenal tumours. It is regarded as the imaging modality of choice because it combines safety with a high rate of detection. It is highly sensitive in the localization of the large adrenal tumours that account for Cushing's syndrome and phaechromocytomas, as well as the small tumours that account for primary hyperaldosteronism. It is, however, not reliable for the detection of adrenal hyperplasia, and does not yield functional imaging information. For small tumours not detectable by CT, and for ectopic tumours, complementary investigations with appropriate application of venous sampling, radionuclide scintigraphy and occasionally arteriography, will be very useful. CT-guided percutaneous biopsy is employed for the incidentalomas in oncologic patients. MRI appears to hold a great potential for the diagnosis of adrenal disorders, but this modality is awaiting wider availability of instrumentation and clearer documentation of techniques.

Treatment of precocious puberty using an intranasal luteinizing hormone‐releasing hormone analogue: Buserelin

Abstract: Fourteen patients with precocious puberty were treated for 1-3 years with 900-1800 micrograms/day of intranasal (i.n.) Buserelin. The peak luteinizing hormone and follicle-stimulating hormone responses to intravenous luteinizing hormone-releasing hormone were reduced significantly 4 weeks after starting treatment and remained suppressed while the patients were on treatment. Two patients were withdrawn because of drug non-compliance. Three patients showed regression of pubertal changes, four patients showed no progression and five patients showed progression of breast size or pubic hair staging after 1.5-2 years of treatment. Treatment was changed to the subcutaneous route in two patients because of hormonal escape and accelerated skeletal maturation. The mean growth velocity decreased from 10.78 cm/year (s.e.m. = 0.64) to 7.06 cm/year (s.e.m. = 0.85) after 1 year of treatment (P less than 0.005). After an increase in dosage (from 900 micrograms/day to 1800 micrograms/day) in most patients, further significant falls in growth velocity to 5.29 cm/year (s.e.m. = 0.45), 4.63 cm/year (s.e.m. = 0.8) and 5.06 cm/year (s.e.m. = 0.5) were observed at 18, 24 and 30 months, respectively, compared with the pretreatment value (P less than 0.001). With treatment, the increased rate of skeletal maturation normalized. In 10 patients who had completed 2 years of treatment, the height standard deviation score for bone age improved from a pretreatment value of -2.42 +/- 0.42 to -1.6 +/- 0.42 after 2 years of treatment (P less than 0.01), indicating an improvement in height prognosis. It is concluded that i.n. Buserelin at a dose of 1800 micrograms/day is effective in the treatment of most but not all patients with precocious puberty.