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Biomedical subjects

S Y Chang

Publications and source records attributed to S Y Chang.

At least 163 records · Page 9Linked to original sources

T cell recognition and cytokine production elicited by common and type-specific glycoproteins of herpes simplex virus type 1 and type 2.

T cell recognition of common and type-specific herpes simplex virus (HSV) glycoproteins was measured in 72 subjects. T cells were stimulated with whole HSV-2 antigen and glycoproteins gB2, gD2, and gG2. T cell proliferation in response to HSV-2 antigen and gG2 was significantly higher in subjects with HSV-2 infection than in those with HSV-1 infection only; responses to gB2 and gD2 were the same. T helper (Th) type 1 and Th2 cytokine production in response to whole HSV-2 antigen, gB2, and gD2 was evaluated in 33 subjects. Interleukin (IL)-2 and interferon-gamma responses to most antigens were significantly higher among HSV-2-seropositive subjects than among seronegative subjects. IL-4 synthesis was negligible; IL-10 was produced in seronegative and seropositive persons, but HSV-2 antigen responses were significantly higher in HSV-2-seropositive persons. Naturally acquired immunity to HSV involves T cell recognition of common and type-specific glycoproteins, prominent Th1 responses, and discordant Th2 responses with little IL-4 but substantial IL-10 production.

Antigens, Viral↗

The relationship between ultrasonic volume and actual weight of pathologic uterus.

Our purpose was to assess the correlation between the estimated volume based on ultrasonic measurement in vivo and the actual weight of the diseased uterus after hysterectomy, and then retrospectively tried to establish a simple equation to convert the volume into the weight in grams. A total of 105 women with nonmalignant diseased uteri which were prepared to undergo laparoscopy-assisted vaginal hysterectomy had had preoperative ultrasound scanning to estimate the uterine size by measuring three dimensions including the length (L), width (W) and anteroposterior (AP) diameter. The uterine volume was calculated by the use of a prolate ellipsoid formula (4/3 x pi x L/2 x W/2 x AP/2). Actual uterine weight was immediately taken after extirpation of the uterus. Linear regression analysis revealed uterine weight (g) = 50.0 + 0.71 x volume (cm3), with correlation coefficient = 0.93 and SE = 49.6 g. There was a close, positive correlation between the estimated uterine volume and actual uterine weight. With utilization of this equation, the uterine size in vivo can thus be expressed as a concrete, objective value in weight instead of "weeks' size' by comparison with pregnant uterus, which has been commonly used in traditional gynecologic practice.

Adult↗

Relationship of uterine perfusion to outcome of intrauterine insemination.

This prospective study was undertaken to evaluate the prognostic value of uterine perfusion on the day of human chorionic gonadotropin administration in patients who were undergoing intrauterine insemination. Uterine perfusion was evaluated by measuring the pulsatility index of the ascending branch of the uterine arteries on the day of administration of human chorionic gonadotropin. No pregnancy occurred when the pulsatility index of the ascending branch of the uterine arteries was more than 3. The fecundity rate was 18% when the pulsatility index was less than 2 and was 19.8% when the pulsatility index was between 2 and 3 (not significant). The continuing pregnancy rate was 18% when the pulsatility index was less than 2, compared with 12.1% when the pulsatility index was between 2 and 3 (P < 0.05). Our data suggest that the measurement of uterine perfusion on the day of human chorionic gonadotropin administration may have predictive value regarding fecundity and the continuation of pregnancy in intrauterine insemination.

Adult↗

Coexpression of beta 1 with cardiac sodium channel alpha subunits in oocytes decreases lidocaine block.

Coexpression of the rat beta 1 subunit with rat brain and skeletal muscle sodium channel alpha subunits in Xenopus oocytes normalizes currents by accelerating sodium current decay kinetics, shifting steady state availability relationships, and accelerating recovery from inactivation. Unlike brain and skeletal muscle, the heart alpha subunit expressed without beta 1 has native-like decay kinetics in oocytes. Messenger RNA for beta 1 has been found in heart, but whether and how it affects cardiac sodium channel function are unclear. We studied coexpression of human heart alpha subunit with beta 1 in Xenopus oocytes using two microelectrode voltage-clamp and macropatch techniques. Coexpression with beta 1 caused a significant positive shift of 3-7 mV in the midpoint of the steady state inactivation relationship but did not affect single-channel conductance, activation, current decay, or recovery from inactivation. Sensitivity to lidocaine block, however, was decreased for both resting state block (Kd = 0.5-1.3 mM) and phasic block in response to pulse trains, but inactivated state block was not affected (Kd = approximately 10 microM). Coexpression with beta 1 increased the rate of recovery from lidocaine block, which accounted for the major part of the observed differences in tonic and phasic block. A beta 1 construct with the cytoplasmic tail removed also produced these effects, demonstrating that the beta 1 cytoplasmic tail was not involved in altering lidocaine block. We conclude that the beta 1 subunit is capable of affecting function of the cardiac sodium channel in oocytes by decreasing tonic and phasic lidocaine block with small effects on gating.

Animals↗

Early discontinuation of gonadotropin-releasing hormone agonist in controlled ovarian hyperstimulation: a preliminary report.

The purpose of this study was to evaluate the applicability of continuing daily injectable GnRHa, after pituitary desensitization, for the first 4 or 5 days of ovarian stimulation. We proposed a new calculation and estimated that it took as early as 6 to 7 days for pituitary and gonadotropin release to return after cessation of daily administered leuprolide acetate. A modified regimen based on this new calculation, i.e. Daily administered GnRHa continued for the first 4 or 5 days with ovarian stimulation after pituitary desensitization had been achieved was applied to patients undergoing assisted reproductive technology (ART). Thirty-five patients prospectively assigned to use this early discontinuation regimen were analyzed with respect to age, indications, duration of ovarian stimulation, dose of exogenous gonadotropin required, ovarian response and oocytes obtained, rate of fertilization, and rates of pregnancy. There was no spontaneous LH surge occurred. Premature luteinization occurred in one patient. We concluded that, after pituitary desensitization, there was no spontaneous LH surge when daily administered GnRHa continued for 4 or 5 days only with ovarian stimulation. Impacts on the ART outcome required further evaluation in a prospectively randomized study. Based on theoretical estimation, cessation of GnRHa at the beginning of ovarian stimulation might eliminate most, but not all, spontaneous LH surges.

Adult↗

Child malnutrition in China--present status and changing trend.

Halving the malnutrition of under five of years has been set as one of the goals to be achieved by the year of 2000 by Chinese government. So it is important to know the present status of child malnutrition and its trend of changing, in order to predict the possible outcome of the achievement of the goal. According to the Child Survey carried out by the State Statistic Bureau (SSB) in 26 provinces and autonomous regions and 3 municipalities in 1992, the prevalence of malnutrition of under five was: moderate and severe underweight, stunting and wasting were 17.9%, 34.7% and 4.7% respectively. But there are significant differences among urban and rural children and between different provinces. The highest prevalence rate usually occurred in the second year of life of the children, and this may be the result of inadequate weaning food provided to the children. As compared with the data collected in 1987 by SSB in 9 provinces and autonomous regions, an impressive improvement in underweight has occurred within these 5 years. The average declined prevalence was 20.5%. It is specially true for urban children. To stunting, there was also improvement for urban children but not in the rural, resulting and over all increasing of prevalence by 5.9%. To wasting, the prevalence for urban children was low and remained at the same level while there was some what increase in the rural. So, according to these results, with constant economic development and more attempt made in areas and groups at risk, the goal to decrease malnutrition in half in terms of underweight could be reached by the year of 2000.

Body Height↗

Autogenous fat intracordal injection as treatment for unilateral vocal palsy.

BACKGROUND: Intracordal injection, which is less time-consuming and avoids neck incision, remains an important method to correct glottic insufficiency induced by unilateral vocal palsy. Among the various new materials proposed for intracordal injection, autogenous fat draws our attention for its availability without cost and high bio-compatibility. This article reports our preliminary experiences of intracordal injection using autogenous fat to treat glottic insufficiency induced by unilateral vocal palsy. METHODS: Autogenous fat is collected under local anesthesia by syringe aspiration from femoral or lower abdomen. Precautions to reduce resorption are taken while collecting and processing the fat. Under the guidance of flexible laryngovideostroboscopy, Bruning syringe with a bended needle is inserted transorally to make the intracordal injection. Serial pre-operation and postoperation evaluations by flexible laryngovideostroboscopy, the patient's selfassessment on the voice, the speech pathologist's perceptual ratings on the breathiness and roughness of the patient's voice, maximum phonation time, and mean airflow rate are made. RESULTS: A total of 19 cases were recruited for the treatment, and 17 of them completed the procedure. The clinical applicability was 89.5%. The fat injection had no obvious effect on the posterior glottic gap correction. The postoperative glottic gap estimated by the videostroboscopy, was improved in 15 of the 16 cases two weeks after operation, and in five of the seven cases who has been followed up for three months. Twelve of the 16 cases felt improved voice in two postoperative weeks, and six of the seven cases still felt the improvement three months after operation. The rate and amount of resorption varied greatly among individuals. None of the injected cords showed untoward morphological or vibratory changes up to three months after injection. CONCLUSIONS: Intracordal injection of autogenous fat to treat unilateral vocal palsy by the method we propose is relatively simple with high clinical applicability and no extra-cost. None of the injected cords showed unfavorable changes. Most of the patients were improved after injection, at least for a short period of time. The long-term effectiveness remains to be observed. Repetition of the injection is also simple, if the voice results deteriorate due to resorption of the injected fat.

Adolescent↗

The effects of Vero cell co-culture on human zygotes resulting from in vitro fertilization and oocytes following subzonal insemination.

A variety of co-culture systems have been devised to enhance the human embryo development in vitro. Vero cells were selected because they can be highly controlled and are easy to handle. To evaluate the embryotrophic effects of Vero cell monolayers, when they were co-cultured with human in vitro fertilized zygotes or subzonal inseminated oocytes. Total 1695 two-pronuclear embryos resulting from in vitro fertilization were cultured with Vero cells or medium alone for 24 hours. Similarly, sixty-six two-pronuclear embryos resulted from subzonal insertion of sperm (SUZI) with co-culture starting immediately following SUZI were compared with fifty-two two-pronuclear embryos resulted from SUZI, without co-culture. The numbers of blastomere and morphology of embryos were compared between the co-culture group and control group using student's t-test. Cell numbers in each embryo were greater in the IVF/co-culture group than in the control group (4.01 +/- 1.32 vs. 3.86 +/- 1.45, p < 0.05). The rates of poor quality embryo with major fragmentation were lower in the co-culture group than in the control group(11.5% vs. 19.9%, p < 0.001, for IVF embryos; 9% vs. 27%, p < 0.005, for SUZI oocytes). Co-culture SUZI oocytes on Vero cells prior to fertilization did not positively influence embryo cleavage, but improved embryo quality. We conclude that Vero cells can enhance human embryo development; however, the period for one-day or two-day co-culture is too short to provide a maximal support. Short term co-culture did not increase implantation rates. Immediate co-culture following SUZI might somewhat rescue the microinseminated oocytes. However, a longer duration of co-culture is necessary to exert the maximal effects on embryo development and implantation.

Adult↗

Multivariate analyses of the relationship between umbilical cord length and obstetric outcome.

To investigate the clinical significance of umbilical cord length in human pregnancies, 1087 deliveries at Kaohsiung Chang Gung Memorial Hospital from May 1995 to August 1995 were studied. Our data showed that male fetuses had longer cord length than female and vertex presentation had longer cord length than breech presentation. The cord length and placental weight were significantly related to the birth weight. We found that: 1) only intrauterine growth retardation was associated with the increased risk of fetal distress; 2) secondary arrest of labor and advanced gestational age were correlated with meconium stain; and 3) birth weight and presence of meconium stain were correlated with the secondary arrest (p < 0.05). However, there was no significant correlation between umbilical cord length and fetal well-being. As a result of multivariate analyses, we conclude that the umbilical cord length does not significantly correlate with either maternal age, gestational age (> or = 28 weeks), parity fetal outcome or intrauterine fetal well-being. Birth weight is the only characteristic that is correlated with cord length.

Adult↗

Second trimester diagnosis of thanatophoric dysplasia.

Thanatophoric dysplasia is one of the most common skeletal dysplasia, with an incidence from 1:6,400 to 1:100,000 births. While the etiology is unknown, either autosomal recessive or polygenic transmission with 0.2% recurrence risk had been suggested. It is a lethal disorder characterized by extremely short ribs, tubular bones and macrocephaly. Death is often secondary to pulmonary hypoplasia caused by the small thoracic cavity. We present a fetus with shortening of four limbs, typical thanatophoric dwarfism, diagnosed by sonography at the 25th week of gestation. The second trimester diagnosis by ultrasound was crucial, because it gave an alternative option of pregnancy termination when the affected fetus was discovered.

Adult↗

Improved sperm recovery rate with Percoll gradient method in intrauterine insemination.

The purpose of this study was to compare the different sperm manipulation methods on the recovery rate of motile sperm that was collected to use in the intrauterine insemination. Three hundred and thirty-five IUI (intrauterine insemination) cycle from a total of 963 treatment cycles was performed for non-peritoneal factor infertility couples. The sperm separation methods were swim-up, swim-down and Percoll gradient (since Mar. 1992). We compared the different sperm preparation methods in normal and abnormal semen analysis group. Our results show that in the abnormal semen samples (oligospermic approximately, asthenospermic approximately), the Percoll gradient method is superior to the swim-up and swim-down methods on the recovery of a higher number of total, motile and active motile spermatozoa (p < 0.05), even though the sperm quality before preparation was rather poorer than the samples prepared by the other two methods. The pregnancy rate in both groups are not statistically significant. We conclude that the Percoll gradient is an improved method for semen manipulation as it allows greater recovery of sperm with higher motility in intrauterine insemination.

Adult↗

Comparison of laparoscopically assisted vaginal hysterectomy and abdominal hysterectomy in taiwan.

In order to clarify the feasibility of laparoscopically assisted vaginal hysterectomy (LAVH) using a not-for-extra charge instrument and to determine its cost-effectiveness in the Taiwan national health care system, we designed a prospective comparison which recruited candidates with nonmalignant uterine tumors prepared for hysterectomy to assess treatment by the laparoscopic versus the laparotomic approach. There were 144 patients in the laparoscopic group and 157 patients in the laparotomic group. The two groups were similar in characteristics. A total of 138 LAVHs were completed with six conversions (4.2%) to abdominal hysterectomy. Intraoperatively, the mean operating time in the LAVH group was longer than in the laparotomic group (134 vs 112 minutes, p < 0.001). No statistically significant differences were found between the two groups in mean estimated blood loss (260 vs 259 mL) and complications (5.8 vs 4.5%). Postoperatively, mean flatulence-relief time (27.4 vs 31.3 hours) and intramuscular meperidine requirements (1.6 vs 2.5 ampoules, 1 ampoule = 50 mg) were significantly less with LAVH. There were no differences in mean hemoglobin levels (10.7 vs 10.9 g/dL), complications (9.4 vs 13.4%, p = 0.288), or hospital stay (4.9 vs 5.2 days, p = 0.058). The mean total hospital charges (NT$48,390 vs 41,649) and insurance-paid costs (NT$43,992 vs 38,389) were significantly greater in the LAVH group. In conclusion, LAVH when performed by an experienced laparoscopist and for adequately selected patients, permits a better short-term convalescence, but is more expensive compared with conventional abdominal hysterectomy.

Adult↗

Leiomyomatosis peritonealis disseminata (LPD) with acute ascites induced by gonadotropin-releasing hormone (GnRH) agonist: a case report.

Leiomyomatosis peritonealis disseminata (LPD) is a rare disorder characterized by the development of numerous leiomyomata throughout the peritoneal cavity. We present a case of a 29-year-old woman who had LPD with acute ascites induced by a GnRH agonist (Supremon; buserelin acetate nasal solution 400 micrograms/per day). We found abdominal wall leiomyomata under the left rectus muscle. Because the disorder tended to recur with acute ascites in this patient, castration was performed to eliminate the hormonal stimulation of tumor growth. We suggest postponing hormone replacement therapy post-operatively for 6 months, and we recommend close follow-up to prevent tumor recurrence and hypoestrogenism.

Acute Disease↗

Comparison between short-term and long-term post-operative evaluation of sleep apnoea after uvulopalatopharyngoplasty.

For a long time uvulopalatopharyngoplasty (UPPP) has been used to treat the obstructive sleep apnoea syndrome (OSAS). The diverse surgical effects, the inadequate understanding of operation effect consistency, the possibility of disease progression, and the few reported papers for long-term evaluation after UPPP aroused our interest in designing this study. Fifteen OSAS patients who had undergone UPPP with pre-operative, initial post-operative and long-term post-operative polysomnographic studies were included in this study. Long-term post-operative polysomnography was undertaken more than five years after surgery. The polysomnographic evaluations included respiratory disturbance index (RDI), duration of saturation SaO2 < 85 per cent (DOS), and the lowest O2 saturation (LOS). Amongst them, 10 patients with initial post-operative RDI reduction > 50 per cent were considered responders. In these responders, the long-term follow-up results of all three parameters showed improvement compared to the pre-operative data. In a comparison between the initial and long-term post-operative sleep study results, LOS and DOS showed no significant difference. However, the long-term post-operative RDI result became significantly worse. More than 80 per cent of all cases had subjective symptomatic improvement in the long-term post-operative evaluation. The subjective improvement after operation is not adequately correlated to the polysomnographic result. We suggest that long-term follow-up for patients after UPPP is necessary.

Adult↗

Founding mutations and Alu-mediated recombination in hereditary colon cancer.

By screening members of Finnish families displaying hereditary nonpolyposis colorectal cancer (HNPCC) for predisposing germline mutations in MSH2 and MLH1, we show that two mutations in MLH1 together account for 63% (19/30) of kindreds meeting international diagnostic criteria. Mutation 1, originally detected as a 165-base pair deletion in MLH1 cDNA comprising exon 16, was shown to consist of a 3.5-kilobase genomic deletion most likely resulting from Alu-mediated recombination. Mutation 2 destroys the splice acceptor site of exon 6. A simple diagnostic test based on polymerase chain reaction was designed for both mutations. Our results show that these two ancestral founding mutations account for a majority of Finnish HNPCC kindreds and represent the first report of Alu-mediated recombination causing a prevalent, dominantly inherited predisposition to cancer.

Base Sequence↗

Neurotoxin quinolinic acid is selectively elevated in spinal cords of rats with experimental allergic encephalomyelitis.

Experimental allergic encephalomyelitis (EAE) is an autoimmune, animal model of multiple sclerosis (MS) in which demyelination and paralysis are evident. Quinolinic acid (QUIN) is a neurotoxin and endogenous N-methyl-D-aspartate receptor agonist formed from tryptophan. The role of neurotoxins in general and QUIN in particular in EAE or MS is unknown. Lewis rats inoculated with myelin basic protein developed signs of EAE by day 12, were killed, and their tissues assayed for QUIN by gas chromatography with mass spectrometry. QUIN levels were significantly elevated in the more caudal regions of the spinal cords of animals with EAE. Brain, serum, and liver levels of QUIN were not altered. In a similar manner, QUIN in mylin basic protein-injected, asymptomatic animals was not different from control animals. The time course for QUIN was similar to the neurological signs of the disorder; however, the initial elevation in QUIN occurred before the appearance of behavioral signs. Last, treatment with the glucocorticoid dexamethasone prevented both the signs of EAE and the elevation in spinal cord QUIN. It is not known whether QUIN contributes to the paralysis in EAE. However, if QUIN is pathogenic in EAE this finding could have therapeutic implications for MS.

Animals↗

Unexpected pregnancies exposed to leuprolide acetate administered after the mid-luteal phase for ovarian stimulation.

Leuprolide acetate (Lupron) belongs to the group of gonadotrophin-releasing hormone agonists (GnRHa). It is used in conjunction with human menopausal gonadotrophin (HMG) and/or follicle stimulating hormone (FSH) for ovarian stimulation in the so-called ultra-short, short or long protocols. In our programme, the long protocol is mainly used, which starts routinely with s.c. administration of Lupron, 1 mg/day, from day 21 of the cycle preceding ovum retrieval. After pituitary desensitization is achieved, gonadotrophin administration is started. However, unexpected, spontaneous pregnancy may occur during the flare-up phase of Lupron administration. We present six pregnancies and four deliveries which have occurred under these circumstances. The mechanisms by which pregnancy may occur and escape from luteolytic, abortifacient and teratogenic effects of prolonged use of GnRHa are discussed, as well as pregnancy outcome.

Adult↗

The expression of ferritin on renal cancers and its relationship with cellular differentiation and tumour stage.

OBJECTIVES: To investigate ferritin expression in renal carcinoma and the correlation of expression with tumour differentiation and stage. PATIENTS AND METHODS: Ferritin was immunohistologically detected in 35 patients (23 men and 12 women; mean age 58.2 years, range 40-82) with renal carcinoma and the findings compared with cellular type, tumour stage and the ferritin expression of a similar control population of 16 patients. RESULTS: The incidence of ferritin expression in renal carcinomas was 51%. Expression was significantly related to tumour stage and not cellular type. CONCLUSION: The results of this study re-emphasize the high expression of ferritin in renal cell carcinoma and the correlation of expression with tumour behaviour.

Adenocarcinoma↗