Biomedical subjects

S Kunathikom

Publications and source records attributed to S Kunathikom.

8 recordsLinked to original sources

PubMed2003

Design of delay elements in a binary optical true-time-delay device that uses a White cell.

A White-cell-based binary optical true-time-delay device has two parts: the controller, or switching engine, and the delay elements. Here we discuss in detail the design of both glass blocks and lens trains as delay elements. Glass blocks can be used in our design for delays ranging from one to a few hundred picoseconds. Lens trains are suitable for longer delays. We also analyze the loss associated with each design and give design limits.

Journal Article↗

PubMed2001

Chromosomal analysis of "failed-fertilized" human oocytes resulting from in-vitro fertilization and intracytoplasmic sperm injection.

To evaluate the incidence of chromosomal abnormalities in "failed-fertilized" oocytes derived from in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) procedure, a cytogenetic analysis was performed on 164 IVF and 64 ICSI oocytes. One hundred and eleven (67.7%) of the IVF and 56 (87.5%) of the ICSI oocytes were successfully karyotyped. Of 111 IVF oocytes, 73 (65.8%) exhibited normal haploid and 38 (34.2%) were abnormal. The abnormalities included 25 aneuploid (22.5%) (7 hyperhaploid and 18 hypohaploid), 11 diploid (9.9%) and 2 structural anomalies (1.8%). Of 56 ICSI oocytes, 52 (92.8%) were normal haploid and only 4 (7.2%) were aneuploid, with 2 hyperhaploid and 2 hypohaploid. The sperm nuclei were observed in 43 IVF oocytes (38.7%), composed of 38 (34.2%) premature chromosome condensation (PCC) and 5 (4.5%) decondensed sperm heads. Evidence of successful sperm delivery was found in all 56 ICSI oocytes; 25.0 per cent (14/56) showed PCC, 17.9 per cent (10/56) showed decondensed sperm heads, and 57.1 per cent (32/56) showed intact sperm heads. This study suggested that about one-third of unfertilized oocytes exhibited chromosomal abnormalities. The difference of aneuploidy between IVF and ICSI oocytes needs further studies analysing a larger number of oocytes.

Adult↗

PubMed1999

Comparison of pronuclear stage embryo transfer and in vitro fertilization-embryo transfer following intracytoplasmic sperm injection.

To determine whether the mode of embryo transfer (PROST vs IVF) affected the outcome in intracytoplasmic sperm injection (ICSI) cycles, 237 ICSI cycles (106 PROST and 131 IVF) were analyzed. Several parameters, including patient age, duration of infertility, amounts of hMG used, number of mature eggs retrieved and injected, fertilization rate, number of embryos transferred, and clinical pregnancy rate, were compared. Most of the variable factors were not significantly different, except the mean numbers of transferred embryos which were significantly higher in the PROST group. The clinical pregnancy rate showed no statistical difference between PROST and IVF cycles (25.5 and 16.8%; p = 0.139). This study suggests that even the pregnancy rate in PROST cycles was slightly higher than IVF cycles, but there was no statistically significant difference between the two groups.

Adult↗

PubMed1998

Comparison of two-layer Percoll gradient and mini-Percoll methods for sperm preparation.

To compare the efficiency of sperm preparation between the two-layer Percoll gradient and mini-Percoll methods, 50 normal and 33 abnormal semen samples from male partners of infertile couples were studied. The number of recovered spermatozoa, percentage of motility, percentage of normal morphology, and their survival at 24 and 48 hours were assessed. Both Percoll gradient techniques resulted in a significantly higher percentage of motility and percentage of normal morphology compared with the original semen samples (p < 0.0001). The two-layer Percoll gradient showed a higher sperm recovery than the mini-Percoll method (p < 0.001), but the latter resulted in a higher percentage of motility (p > 0.001) and a higher sperm survival rate at 24 hours (p < 0.05) than the former, regarding normal semen samples. These differences did not appear with abnormal semen samples when analyzed as a group. Considering each of the abnormal parameters separately, sperm recovery was significantly higher after the two-layer Percoll gradient in the case of astheno- and teratozoospermia (p < 0.05), but sperm survival at 48 hours was higher after the mini-Percoll gradient in the case of teratozoospermia (p < 0.05). It is concluded that both the two-layer Percoll gradient and mini-Percoll method can be used effectively for sperm preparation. The former yields a higher sperm recovery, but the latter should be considered regarding teratozoospermic samples and semen samples of very low volume.

Factor Analysis, Statistical↗

PubMed1997

Primary amenorrhoea: a retrospective study at Siriraj Hospital.

To determine the incidence of etiologic factors responsible for primary amenorrhoea in Siriraj Hospital on the basis of clinical examination and laboratory investigations. A retrospective study was performed from the records of patients who attended the Reproductive endocrine Clinic at Siriraj Hospital from 1 September 1992 to 31 August 1995. During the 3 years of the study period, there were 110 cases of primary amenorrhoea. One hundred and one cases were analyzed: nine cases were excluded because the patients lost follow-up before the final diagnosis could be concluded. The two most common etiologic factors were mullerian agenesis (39.65%) and gonadal dysgenesis (32.69%). Mean age of the patients when they first consulted the physicians was 22.45 +/- 6.06 years. Karyotyping was done on 28 of 32 cases of gonadal dysgenesis; 46,XX karyotype was found in 50 per cent and 45,XO in 14.29 per cent of analyzed cases. Clinical examination gave wrong diagnosis of absent uterus in 4 cases who were in the hypoestrogenic stage with hypoplastic uterus; ultrasonography and laparoscopy gave the wrong diagnosis in 1 case each in our report. These patients successfully menstruated after hormonal replacement therapy. The incidence of etiologic causes and cytogenetic study of primary amenorrhoea in our study is different from earlier reports. Racial and environmental differences may play a role in these differences. The facilities of diagnostic tools may also play a part. However, both clinical examination and many laboratory investigations have to be completed before final diagnosis of etiologic causes of primary amenorrhoea are elucidated. Diagnosis based on inadequate data can be misleading.

Adolescent↗

PubMed1997

Cryopreservation of human spermatozoa: comparison of two cryoprotectants and two freezing methods.

A prospective experimental study was performed to compare sperm cryosurvival rate between two kinds of cyroprotective media: citrate-egg yolk-glycerol (CEG) and TEST-citrate-egg yolk-glycerol (TEST-EYG), and between two freezing methods: noncontrolled rate (NCR) freezing and computer controlled rate (CR) freezing. One hundred semen samples were included in the study. Each sample was divided into two parts, which were prepared as two CEG and two TEST-EYG mixture straws, then one straw from each mixture was frozen by the NCR-freezing method and the complementary straw was frozen by the CR-freezing method. After one week of cryostorage, the straws were thawed and the post-thaw sperm survival was assessed. As the results, the post-thaw sperm survival rate of the CEG media group was slightly higher than the TEST-EYG group in both the NCR-freezing method (51.2% vs 47.0%, p < 0.05) and the CR-freezing method (48.2% vs 43.4%, p < 0.05); and similarly; the NCR-freezing group yielded a slightly higher post-thaw sperm survival rate than the CR-freezing group in both the CEG media used (51.2% vs 48.2%, p < 0.05) and the TEST-EYG media used (47.0% vs 43.4%, p < 0.05). However, these did not have clinical significance because the differences were too small. In conclusion, the use of either CEG or TEST-EYG media, and either the NCR or CR-freezing method did not have clinical differences on the post-thaw sperm survival.

Adult↗

PubMed1996

Long-acting triptorelin for the treatment of endometriosis.

OBJECTIVE: To evaluate the efficacy and adverse effects of monthly triptorelin injection for the treatment of endometriosis. METHODS: A multicenter clinical trial including 45 women with endometriosis, treated with triptorelin 3.75 mg i.m. every 4 weeks in six consecutive doses. The main outcome measures were symptom relief, reduction according to revised American Fertility Society (rAFS) scores, reduction in size of ovarian endometrioma, effects on hormone and lipid profiles, changes in bone mineral density (BMD), adverse effects, and return of menstruation. Data were analyzed using repeated measures analysis of variance and paired t-tests. RESULTS: Pain-related symptoms decreased in all cases after 8 weeks of treatment. Laparoscopic assessment revealed a reduction in rAFS scores in 21 out of 25 cases (mean pretreatment scores 43.44 +/- 5.75 vs. post-treatment scores 22.30 +/- 3.40, P < 0.001). The size of ovarian endometrioma decreased in eight of nine women but none disappeared. Serum luteinizing hormone, follicle-stimulating hormone and estradiol levels were effectively suppressed during treatment. A slight increase in cholesterol and triglyceride levels was observed but all values were within normal limits. After 24 weeks of treatment there was a slight decrease in BMD of total body, lumbar vertebrae and femoral neck but not radius. The main adverse effects included hot flushes, night sweating, vaginal dryness, headache, dizziness and nausea Menstruation returned 83.76 +/- 2.91 days after the last injection of triptorelin. CONCLUSION: Long-acting triptorelin is efficacious in the treatment of endometriosis and has tolerable side effects.

Adult↗

PubMed1995

Relationship between the direct mixed antiglobulin reaction (MAR) test and spontaneous sperm agglutination in men from infertile couples.

To determine the relationship between the direct MAR test and spontaneous sperm agglutination in men from infertile couples, semen samples from 160 men were studied. Spontaneous sperm agglutination was present in 80 samples, and absent in the others. Routine semen analysis and the direct MAR test were performed on all samples. The incidence of positive MAR tests in samples with and without spontaneous sperm agglutination were 15 and 0 per cent respectively (p < 0.05). There were no significant differences in mean sperm concentration, motility, and morphology between the samples with and without spontaneous sperm agglutination, and between the positive and negative MAR test groups. It can be concluded that spontaneous sperm agglutination relates significantly to antisperm antibodies detected by the direct MAR test, and this factor could be used as indication for antisperm antibody testing of infertile men.

Coombs Test↗