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Wirawit Piyamongkol

Publications and source records attributed to Wirawit Piyamongkol.

12 recordsLinked to original sources
PubMed2006

A successful strategy for Preimplantation Genetic Diagnosis of beta-thalassemia and simultaneous detection of Down's syndrome using multiplex fluorescent PCR.

OBJECTIVES: Preimplantation Genetic Diagnosis (PGD) is an alternative to prenatal diagnosis providing couples the chance to start a pregnancy with an unaffected fetus. The objective of the present study was to develop and apply quick, sensitive and accurate single cell PCR protocols for PGD of beta-thalassemia and Down's syndrome detection. MATERIAL AND METHOD: Two couples carrying beta-thalassemia codon41-42 mutation underwent routine IVF procedures. Embryo biopsy was performed on Day-3 post-fertilisation and single cell multiplex fluorescent PCR was employed for mutation analysis, contamination detection and diagnosis of trisomy 21 cases. RESULTS: Seventeen embryos were tested in two clinical PGD cycles. This resulted in the first birth following PGD for a single gene disorder in Thailand and South East Asia, confirmed by prenatal testing. Two embryos were shown to be affected by Down's syndrome. CONCLUSION: Successful strategy for PGD of beta-thalassemia and Down's syndrome detection using multiplex fluorescent PCR was introduced.

Adult↗
PubMed2006

Comparison of the manual stimulation test and the nonstress test: a randomized controlled trial.

OBJECTIVE: To evaluate manual fetal stimulation (MST) through the maternal abdomen in comparison to standard nonstress test (NST) in terms of nonreactive rates and testing time. MATERIAL AND METHOD: Five hundred and forty high-risk singleton pregnancies at 28 gestational weeks or more were assigned to have either NST or MST using blocked randomization (270 each). All fetal heart rate (FHR) tracings were analyzed blindly using standard NST criteria by one perinatologist. RESULTS: The MST group provided a significantly higher reactive rate than that of the NST group, 98.9% and 84.4% respectively, p < 0.001. Mean testing time of the reactive results of the MST group was also significantly shorter than that of the NST group, 7.94 +/- 6.27 min and 13.91 +/- 9.58 min respectively, p < 0.001. CONCLUSION: This is the first randomized controlled trial (RCT) to demonstrate the distinctive benefit of the simple and less expensive MST. MST significantly reduces the time to reactivity and increases the frequency of reactivity when compared to NST alone.

Adult↗
PubMed2005

Accuracy of fetal heart-rate variability interpretation by obstetricians using the criteria of the National Institute of Child Health and Human Development compared with computer-aided interpretation.

AIM: To evaluate the accuracy of fetal heart rate variability interpretation by obstetricians using the criteria of the National Institute of Child Health and Human Development (NICHD), compared with computer-aided analysis as a gold standard. METHODS: One hundred and fourteen panels of fetal heart-rate tracings derived from electrocardiogram via scalp electrodes obtained from women with high-risk pregnancies during the intrapartum period. The tracings were interpreted using computer analysis and recorded as a gold standard. The same tracings were distributed to six observers: three residents in the third year of training and three faculty members. All observers blindly interpreted the fetal heart-rate variability without the knowledge of the computer analysis. The main outcome measures were: (i) the accuracy of fetal heart-rate variability interpretation by obstetricians using the NICHD criteria compared with computer-aided analysis was presented as a percentage value; and (ii) the agreement of fetal heart-rate variability interpretation between the obstetricians and the computer analysis using the NICHD criteria was presented as a kappa-value. RESULT: When using the computer analysis as a gold standard, the accuracy of fetal heart-rate variability interpretation in the residents group was 81.58%, 86.84% and 82.46%, respectively, with a mean of 83.62%, whereas the accuracy of the faculty members was 79.82%, 67.54% and 79.82%, respectively, with a mean of 75.73%. kappa-values, representing the agreement of interpretation, were 0.70, 0.78 and 0.72, with a mean of 0.73 +/- 0.04 among the residents, and 0.67, 0.50 and 0.68, with a mean of 0.62 +/- 0.10 among the faculty members. Agreements in the two groups were not significantly different (Student's t-test, P=0.14). CONCLUSION: Using the NICHD criteria, the accuracy and agreement of fetal heart-rate variability interpretation in the third-year residents and faculty members are substantial. There was no difference between the groups with regard to the agreement of fetal heart-rate variability interpretation.

Arrhythmias, Cardiac↗
PubMed2005

One year study of Implanon on the adverse events and discontinuation.

OBJECTIVE: To determine adverse events and discontinuation of Implanon in healthy Thai women between 16 and 45 years of age. DESIGN: Prospective descriptive study. SETTING: Family Planning Unit, Department of Obstetrics and Gynecology, Faculty of Medicine, Chiang Mai University. SUBJECTS: Ninety-two female volunteers with eligible criteria, no contraindication for hormonal contraceptive and wished to have long-term contraception were recruited. MAIN OUTCOME MEASURES: Determination of adverse events was done three months after Implanon insertion. Discontinuation of Implanon use was reviewed during the study period of one year RESULTS: Amenorrhea (40.2%) and infrequent bleeding (39.1%) were the most menstrual adverse events. While most non-menstrual adverse events were headache/dizziness (27.2%) and lower abdominal pain (23.9%). Severe non-menstrual side effect was rare (1-2%). Seven subjects (7.6%) discontinued using Implanon during the one year period of study. CONCLUSION: Implanon demonstrated a high continue rate at the first year of insertion. It produced similar adverse events like other progestin-only contraceptives. Counseling before insertion is important for increased client satisfaction and a higher continuation rate.

Adolescent↗
PubMed2005

Feto-maternal hemorrhage after cordocentesis at Maharaj Nakorn Chiang Mai Hospital.

OBJECTIVE: To evaluate the incidence and volume of feto-maternal hemorrhage following cordocentesis. STUDY DESIGN: Descriptive study. MATERIAL AND METHOD: One hundred and sixteen asymptomatic non-anemic pregnant women with an indication for cordocentesis at 18-22 weeks of gestation between January and June 2004 were recruited. Maternal blood samples were obtained immediately before and 30 minutes after cordocentesis. Fetal cells in the maternal blood were counted using Kleihauer Betke test. About 25,000 maternal cells per slide were scanned by the same examiner. Feto-maternal hemorrhage was considered significant if the fetal bleeding was more than 0.25 ml. RESULTS: There was a significant increase in fetal blood volume in maternal circulation after cordocentesis (Paired Students t test, p < 0.001). A significant hemorrhage (> 0.25 ml) occurred in 63 from 116 women (54. 7%). Only one had marked hemorrhage of more than 5.0 ml and none had massive hemorrhage (> 15 ml). CONCLUSION: Cordocentesis at 18-22 weeks of gestation can be associated with feto-maternal hemorrhage in more than half of the cases but nearly all cases had only minimal hemorrhage and none had massive hemorrhage.

Adolescent↗
PubMed2005

Experience of the first 50 cases of cordocentesis after training with model.

OBJECTIVE: To describe the experience of the first 50 cases of cordocentesis after practicing with cordocentesis model. MATERIAL AND METHOD: Cordocentesis model consisted of a water-filled transparent glass box covered with a rubber latex sheet with or without piece of pork skin. A 30-cm umbilical cord filled with mercurochrome, hung inside the container, was the target for the puncture. As in real practice, the trainee had to try to aspirate the red mercurochrome from the umbilical cord using a spinal needle under ultrasonographic guidance. After practicing with the model for 300 procedures, the trainee was allowed to perform cordocentesis on pregnant women at gestational age of 18-22 weeks by herself under expert supervision with time limit of 30 minutes. The procedure not successful in 30 minutes was considered failure. Duration of procedures, placental site, puncture site, and related complications were recorded for subsequent analysis. RESULTS: After practicing with model for 300 procedures, real cordocentesis was performed by the trainee on 50 pregnant women. The success rate in obtaining fetal blood within 30 minutes was 100%. Most of them (92%) took less than 10 minutes to complete the procedure. Puncture site bleeding and fetal bradycardia were the most common immediate complications, found in 30% and 8% respectively, and spontaneously resolved within few minutes. CONCLUSION: Without any fetal and maternal jeopardy, cordocentesis model is simple, inexpensive but highly effective for the beginner to gain their experience, skill and prepare themselves for cordocentesis with confidence. However, the reduction of fetal loss rate with the training program remains to be further tested.

Cordocentesis↗
PubMed2004

Mammographic change in hysterectomized women on 0.625 mg/day of conjugated equine estrogen.

OBJECTIVE: To compare the mammographic change before and after conjugated equine estrogen (CEE) 0.625 mg/day in hysterectomized women. DESIGN: A retrospective descriptive study. SETTING: Menopause clinic, Maharaj Nakorn Chiang Mai Hospital. MATERIAL AND METHOD: Dedicated mammograms and demographic data of 66 women who had been hysterectomized were reviewed. Post surgical menopausal women were recruited for the study. CEE 0.625 mg/day was given just after the operation. The baseline mammography was done before the initiation of HRT and they were compared with the follow-up mammography performed 12-18 months after therapy. The degree of increase in mammographic density was classified as follows: minimal changes (10-25% increased density), moderated change (26-50% increased density), and marked change (> 50% increased density). RESULTS: The mean age +/- SD was 47 +/- 4.3 years old. The mean duration +/- SD of hormone used was 13.5 +/- 2.4 months. The most common indication for operation was myoma uteri (43.9%). On the baseline mammogram, 5 cases had cystic change and one case had a small circumscribed solid mass suspected to be fibroadenoma. On the follow-up mammograms, there were 2 cases (3.0%) detected to have significantly increased breast density. One was moderately increased and the other was markedly increased, but cystic changes and one fibroadenoma were not changed. CONCLUSION: CEE has little effect on increased mammographic density.

Adult↗
PubMed2004

Immediate complications of laparoscopic tubal sterilization: 11 years of experience.

OBJECTIVE: To evaluate the complications of laparoscopic tubal sterilization. METHOD: A retrospective study of laparoscopic tubal sterilization performed at Maharaj Nakorn Chiang Mai Hospital, Faculty of Medicine, Chiang Mai, Thailand was conducted. The details of the operation, including complications and operation time were collected from the operative and family planning registry. RESULTS: Between January 1987 and December 1997, 948 cases of laparoscopic tubal sterilization were performed as an outpatient setting. The combination of intravenous sedation and local anesthesia was employed in all cases. Minor intra-operative complications were found in 4.6% of cases. The most frequent complications were meso-salphingeal and meso-ovarian bleeding. No serious complication was found in this study. The mean operation time was 19.3 minutes (range 5-75 minutes). CONCLUSION: The present study suggested that out-patient laparoscopic tubal sterilization under the combination of intravenous sedation and local anesthesia is a convenient and relatively safe procedure.

Adolescent↗
PubMed2003

Single-cell sequencing and mini-sequencing for preimplantation genetic diagnosis.

There is increasing interest in the use of preimplantation genetic diagnosis (PGD) as an alternative to routine prenatal diagnosis. However, the costs associated with development and testing of new PGD protocols have forced some PGD centres to limit the number of diseases for which PGD is offered. One of the main factors in the design of new protocols, which affects cost and accuracy, is the choice of the mutation-detection technique. We have assessed the reliability of DNA sequencing and mini-sequencing for clinical diagnosis at the single-cell level and have found them to be rapid and accurate. Extensive optimisation for individual mutations is not usually necessary when employing these versatile techniques and consequently a smaller investment of time and resources should be required during development of new protocols. Additionally, we report single-cell protocols for the diagnoses of cystic fibrosis, sickle cell anaemia and beta-thalassaemia, which utilise mini-sequencing. Unlike most mutation-detection techniques, mini-sequencing permits analysis of very small DNA fragments. Small amplicons experience low allele dropout (ADO) rates, and consequently this approach could potentially improve the reliability of PGD.

Anemia, Sickle Cell↗
PubMed2003

Detailed investigation of factors influencing amplification efficiency and allele drop-out in single cell PCR: implications for preimplantation genetic diagnosis.

Preimplantation genetic diagnosis (PGD) of single gene disorders relies on PCR-based tests performed on single cells (polar bodies or blastomeres). Despite the use of increasingly robust protocols, allele drop-out (ADO; the failure to amplify one of the two alleles in a heterozygous cell) remains a significant problem for diagnosis using single cell PCR. In extreme cases ADO can affect >40% of amplifications and has already caused several PGD misdiagnoses. We suggest that an improved understanding of the origins of ADO will allow development of more reliable PCR assays. In this study we carefully varied reaction conditions in >3000 single cell amplifications, allowing factors influencing ADO rates to be identified. ADO was found to be affected by amplicon size, amount of DNA degradation, freezing and thawing, the PCR programme, and the number of cells simultaneously amplified. Factors found to have little or no affect on ADO were local DNA sequence, denaturing temperature (94 or 96 degrees C) and cell type. Consideration of the causal factors identified during this study should permit the design of PGD protocols that experience little ADO, thus improving the accuracy of PGD for single gene disorders.

Alleles↗
PubMed2002

Preimplantation genetic diagnosis for single gene disorders: experience with five single gene disorders.

We report our experience of 14 preimplantation genetic diagnosis (PGD) cycles in eight couples carrying five different single gene disorders, during the last 18 months. Diagnoses were performed for myotonic dystrophy (DM), cystic fibrosis (CF) [Delta F508 and exon 4 (621+1 G>T)], fragile X and CF simultaneously, and two disorders for which PGD had not been previously attempted, namely neurofibromatosis type 2 (NF2) and Crouzon syndrome. Diagnoses for single gene disorders were carried out on ideally two blastomeres biopsied from Day 3 embryos. A highly polymorphic marker was included in each diagnosis to control against contamination. For the dominant disorders, where possible, linked polymorphisms provided an additional means of determining the genotype of the embryo hence reducing the risk of misdiagnosis due to allele dropout (ADO). Multiplex fluorescent polymerase chain reaction (F-PCR) was used in all cases, followed by fragment analysis and/or single-stranded conformation polymorphism (SSCP) for genotyping. Embryo transfer was performed in 13 cycles resulting in one biochemical pregnancy for CF, three normal deliveries (a twin and a singleton) and one early miscarriage for DM and a singleton for Crouzon syndrome. In each case the untransferred embryos were used to confirm the diagnoses performed on the biopsied cells. The results were concordant in all cases. The inclusion of a polymorphic marker allowed the detection of extraneous DNA contamination in two cells from one case. Knowing the genotype of the contaminating DNA allowed its origin to be traced. All five pregnancies were obtained from embryos in which two blastomeres were biopsied for the diagnosis. Our data demonstrate the successful strategy of using multiplex PCR to simultaneously amplify the mutation site and a polymorphic locus, fluorescent PCR technology to achieve greater sensitivity, and two-cell biopsy to increase the efficiency and success of diagnoses.

Adult↗