Biomedical subjects

J L Hwang

Publications and source records attributed to J L Hwang.

At least 37 records · Page 2Linked to original sources

PubMed1992

Effect of the number and depth of embryos transferred and unilateral or bilateral transfer in tubal embryo transfer (TET).

PURPOSE: Our purpose was to evaluate the possible effects of the number of embryos transferred, the depth of embryos placed within the tube(s), and unilateral or bilateral tubal transfer on pregnancy initiation in tubal embryo transfer (TET). METHODS: One hundred eight consecutive TET cycles were analyzed. Oocyte retrievals were carried out by transvaginal ultrasound-guided aspiration of follicles. Forty-eight hours after oocyte retrieval, the developing embryos at the stage of two to four cells were transferred into the fallopian tube(s) by laparoscopy. A maximum of four embryos was transferred to each patient. RESULTS: The pregnancy rates were similar among the cycles in which two, three, or four embryos were transferred. In addition, there was no significant difference in the pregnancy rate whether the embryos were deposited > 4 cm or between 3 and 4 cm into the tube(s). Although the pregnancy rate was greater in cycles of bilateral tubal transfer, the difference from that of unilateral transfers was not significant. CONCLUSION: Our data indicate that when two to four embryos were transferred and the embryos were placed > or = 3 cm within the tube(s), unilateral or bilateral tubal transfer had little influence on the ultimate success of TET.

Embryo Transfer↗

PubMed1992

The role of blocking factors and antipaternal lymphocytotoxic antibodies in the success of pregnancy in patients with recurrent spontaneous abortion.

OBJECTIVE: To elucidate the role of mixed lymphocyte reaction blocking factors (BF) and complement-dependent antipaternal lymphocytotoxic antibodies on the outcome of pregnancy in unexplained recurrent spontaneous aborters. DESIGN: A controlled study of immunotherapy in which the treated group was immunized with the husband's or a third party donor's lymphocytes and the control group received autologous lymphocytes. SETTING: Tertiary care institution. PATIENTS: Forty-three patients in the control group and 48 patients in the treated group. INTERVENTION: The before and after immunization levels of BF and antipaternal lymphocytotoxic antibodies were measured. MAIN OUTCOME MEASURES: The existence or changing pattern of BF and antipaternal lymphocytotoxic antibodies levels before and after immunization had no influence on the pregnancy outcome in either group of patients. CONCLUSION: Neither BF nor antipaternal lymphocytotoxic antibodies is essential for successful pregnancy. They probably reflect the immunological response of the mother to exposure to fetal antigens.

Abortion, Habitual↗

PubMed1992

Treatment and outcome of unexplained recurrent spontaneous abortions in subclinical autoimmune disorders.

Patients with a history of three or more fetal losses before a gestational age of 20 weeks were examined. Only patients with normal chromosomal, hormonal and anatomic findings were included in this study. These patients were tested for the antinuclear antibody, the C3 and C4 levels, anti-ENA [Ro(SSA), La(SSB), SM, RNP, scl-70], anti-single-stranded DNA and anti-double-stranded DNA, lupus anticoagulant, anticardiolipin and antiphosphotidylserine. All of these patients were free of any symptoms, except for the repeated abortions. The results showed that 10 out of 213 (4.7%) patients with unexplained recurrent spontaneous abortions had abnormal serologic tests, and 28% of the abortions (nine out of 32 abortions) occurred during the second trimester. With treatment of low-dose aspirin alone, or in combination with prednisolone, two out of 11 pregnancies in these 10 patients resulted in repeated abortions (18%), which was significantly lower than their previous abortion rate where 32 out of 33 pregnancies resulted in abortions (97%). Four babies (three term and one premature) were delivered without any abnormalities and the other five pregnancies are beyond the 28th week of gestation and are progressing smoothly. This study revealed that subclinical autoimmune disorders may play a role in recurrent spontaneous abortions and adequate treatment can improve the pregnancy outcome.

Abortion, Habitual↗

PubMed1992

Pregnancy after transfer of frozen-thawed human embryos.

Cryopreservation of human embryos has been successfully applied in in vitro fertilization (IVF) and embryo transfer (ET) programs at the National Taiwan University Hospital since 1988. Our preliminary results with 120 frozen-thawed embryos in 31 transfer cycles showed that the survival rate of frozen embryos was 66%. Following transfer, the implantation rate and clinical pregnancy rate were 6.5% and 13%, respectively. Four clinical pregnancies and one preclinical pregnancy following a frozen-thawed embryo transfer were achieved. Two normal male babies have been delivered and another pregnancy is progressing without any problem.* Unfortunately, one pregnancy was terminated due to intrauterine fetal death discovered at the 10th week of gestation; chromosome abnormality (47, XX, +5) of the fetus was found. The single preclinical pregnancy showed an elevation of serum beta-human chorionic gonadotropin levels for three consecutive weeks following ET, but no definite gestational sac was visualized by transvaginal ultrasound.

Adult↗

PubMed1991

Translaparoscopic tubal embryo transfer: preliminary experience at National Taiwan University Hospital.

Forty-six couples with various causes of infertility were treated by tubal embryo transfer. Oocyte retrievals were carried out under ultrasound guidance transvaginally and embryos were transferred 48 hours later by laparoscopy into fallopian tubes. Totally 52 cycles were stimulated and 45 retrievals were performed with an average of 8.1 oocytes per retrieval. The average fertilization rate was 54.8%. The implantation rate was 23.8% and the pregnancy rate was 53.5% per transfer. The pregnancy rate per transfer was comparable whether 3 or 4 embryos were transferred. Nine (39.1%) of the 23 pregnancies had multiple pregnancies. Six cases (26.1%) aborted in the first trimester and the remaining 17 were ongoing or term delivery.

Adult↗

PubMed1991

Pregnancy following oocyte donation and tubal embryo transfer in patients with premature ovarian failure: report of two cases.

Two pregnancies in patients with premature ovarian failure utilizing donated oocytes, in-vitro fertilization (IVF) and tubal embryo transfer (TET), are reported. The recipients received cyclic hormone replacement therapy for six months to prepare the endometrium for implantation. An evaluation cycle was tested to document that the hormone milieu established by the hormone replacement protocol was similar to that of a natural ovulatory cycle. During the oocyte donation cycle, the recipient received incremental estrogen replacement treatment of flexible length during the follicular phase of the donor's stimulated cycle to synchronize the recipient's endometrium to the donor's embryo. Concurrently, the donor underwent controlled ovarian hyperstimulation and transvaginal ultrasound-guided oocyte retrieval. After fertilization of the donated oocytes with sperm from the recipient's husband and cleavage of the fertilized oocytes into the 2- to 4-cell stage, laparoscopic embryo transfer into the recipient's fallopian tube was performed. Case 1 received 4 embryos by the TET procedure. Pregnancy was confirmed by visualization of a gestational sac in the uterine cavity 3 weeks after TET, but miscarriage occurred at the tenth gestational week. In Case 2, the pregnancy was established after TET of 2 embryos. Estrogen and progesterone supplements were maintained until day 100 after TET. The patient delivered a healthy male baby, weighing 2,520 g at 38 weeks of gestation.

Adult↗

PubMed1991

The use of a long-acting gonadotropin-releasing hormone analog(D-Trp-6-LHRH) for improvement of ovarian stimulation in assisted conception programs.

To assess the efficacy of gonadotropin-releasing hormone analog (GnRHa) as an adjuvant in controlled ovarian stimulation in assisted conception programs, 114 infertile patients, who were treated by in vitro fertilization and embryo transfer (n = 61) or tubal embryo transfer (n = 53), were randomized sequentially to receive ovarian stimulation according to two protocols. In protocol 1 (n = 57), long-acting GnRHa (D-Trp-6-LHRH) microcapsules were administered intramuscularly at menstruation and ovarian stimulation using follicle-stimulating hormone (FSH) and human menopausal gonadotropin (hMG) was started 2 to 3 weeks later when the pituitary was completely suppressed. In protocol 2 (n = 57), patients received FSH and hMG from day 3 of the cycle without GnRHa pre-treatment. We found that premature luteinization did not occur in patients treated with protocol 1, and the number of cycles cancelled was also decreased. The days of ovarian stimulation and the amount of hMG required to achieve adequate follicular development were significantly higher in protocol 1 than that in protocol 2. Similarly, the mean serum estradiol levels on the day of human chorionic gonadotropin administration, number of large follicles (mean diameter greater than 10 mm), number of oocytes recovered and number of embryos obtained were also significantly higher in patients treated with protocol 1. The data suggest that the use of D-Trp-6-LHRH as an adjuvant in ovarian stimulation is associated with a lower incidence of cycle cancellation and an improvement in ovarian response in assisted conception programs.

Adult↗

PubMed1990

Induction of topoisomerase II gene expression in human lymphocytes upon phytohemagglutinin stimulation.

The carboxyl-terminal one-third of human topoisomerase II polypeptide expressed in Escherichia coli was used as antigen to generate polyclonal antibodies in rabbits. With the use of antiserum, DNA topoisomerase II levels of phytohemagglutinin-stimulated human lymphocytes were measured by immunoblotting. Our results showed that the increase in intracellular topoisomerase II level paralleled the entry of cells into proliferation. We also found that the increase in the topoisomerase II level resulted from an increase in the amount of topoisomerase II mRNA. The time course study indicated that the appearance of topoisomerase II mRNA was first observed at 36 h after phytohemagglutinin stimulation. The maximal level of topoisomerase II mRNA was seen at 45 h after stimulation. The same RNA blot was rehybridized with a thymidine kinase probe. The maximal level of thymidine kinase mRNA was observed at 39 h after phytohemagglutinin stimulation. In a comparison of the time course of topoisomerase II gene expression with that of [3H]thymidine incorporation and thymidine kinase gene expression, it was found that the expression of the topoisomerase II gene was later than the onset of DNA replication. Thus, this study suggests that topoisomerase I, which is constantly expressed throughout the cell cycle, might participate in the initiation of DNA replication, while topoisomerase II is involved in solving the DNA topological problems accompanying DNA strand separation during DNA replication.

Cells, Cultured↗

PubMed1990

Characterization of adriamycin-resistant human breast cancer cells which display overexpression of a novel resistance-related membrane protein.

Development of multidrug resistance due to overexpression of P-glycoprotein (Pgp), a cell membrane drug efflux pump, occurs commonly during in vitro selections with adriamycin (Adr). Pgp-mediated drug resistance can be overcome by the calcium channel blocker verapamil (Vp), which acts as a competitive inhibitor of drug binding and efflux. In order to identify other mechanisms of Adr resistance, we isolated an Adr-resistant subline by selecting the human breast cancer cell line MCF-7 with incremental increases of Adr in the presence of 10 microgram/ml verapamil. The resultant MCF-7/AdrVp subline is 900-fold resistant to Adr, does not overexpress Pgp, and does not exhibit a decrease in Adr accumulation. It exhibits a unique cross-resistance pattern: high cross-resistance to the potent Adr analogue 3'-deamino-3'-(3-cyano-4-morpholinyl)doxorubicin, lower cross-resistance to the alkylating agent melphalan, and a sensitivity similar to the parental cell line to vinblastine. The levels of glutathione and glutathione S-transferase are similar in the parental line and the Adr-resistant subline. Topoisomerase II-DNA complexes measured by the potassium-sodium dodecyl sulfate precipitation method shows a 2-3 fold decrease in the resistant subline. The MCF-7/AdrVp cells overexpress a novel membrane protein with an apparent molecular mass of 95 kDa. Polyclonal antibodies raised against the P-95 protein demonstrate a correaltion between the level of expression and Adr resistance. Removal of Adr but not verapamil from the selection media results in a decline in P-95 protein levels that parallels a restoration of sensitivity to Adr. Immunohistochemistry demonstrates localization of the P-95 protein on the cell surface. The demonstration of high levels of the protein in clinical samples obtained from patients refractory to Adr suggests that this protein may play a role in clinical drug resistance.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1990

Serum copper and zinc levels in patients with cervical cancer.

The serum copper (SCL) and zinc (SZL) levels were measured in 99 patients with cervical cancer and 50 patients with uterine myoma as controls. The mean SCL in the control group was 109.4 +/- 17.4 micrograms/ml as compared to 117.1 +/- 14.6 micrograms/dl and was not significant (NS) in 17 carcinoma in situ (CIS) patients, 142.3 +/- 14.2 micrograms/dl in 30 stage I patients (p less than 0.001), 159.0 +/- 16.6 micrograms/dl in 22 stage II patients (p less than 0.001), 171.6 +/- 25.7 micrograms/dl in 10 stage III or IV patients (p less than 0.001), and 166.2 +/- 32.2 micrograms/dl in 20 recurrent patients (p less than 0.001). The SCL returned to control level 2 weeks after surgical treatment for the stage I and II patients (mean 110.6 +/- 19.6 and 108.7 +/- 20.4 micrograms/dl, respectively, p less than 0.001). The SZL was 97.2 +/- 15.8 micrograms/dl in control patients and only showed a significant decrease in stage III or IV and recurrent patients (67.2 +/- 16.6 and 70.4 +/- 17.2 micrograms/dl, respectively). Concerning the copper/zinc ratio, the control group was 1.13 +/- 0.07 as compared to 1.17 +/- 0.07 in CIS (p = 0.06), 1.51 +/- 0.24 in stage I (p less than 0.001), 1.85 +/- 0.37 in stage II (p less than 0.001), 2.66 +/- 0.61 in stage III or IV (p less than 0.001), and 2.50 +/- 0.75 in recurrent patients (p less than 0.001). Taking mean +/- 2.5 SD of the control values as cut off points, the percentages of the recurrent patients with abnormal SCL, SZL, and a Cu/Zn ratio were 65, 30 and 90%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1990

Placenta increta in the second trimester of pregnancy: report of a case.

A rare case of placenta increta in the second trimester of pregnancy is reported. The patient was at 15 weeks gestation when the pregnancy, which had been complicated by a maternal rubella infection, was terminated at a regional hospital. However, vaginal bleeding persisted after the operation in spite of medication to control bleeding. Curettage of the uterine cavity one month later failed to reveal any retained placental tissue or other pathology. Therefore, an exploratory laparotomy was performed, yet nothing particular was found in the peritoneal cavity. So, the patient was transferred to our department. Sonography revealed a lower uterine mass of 4.0 x 3.3 cm in size. A persistently low serum hCG titer was also found. Placenta accreta was highly suspected. Three doses of methotrexate were given to control bleeding, yet without results. Hysterectomy was finally performed. A histological study revealed placenta increta.

Adult↗

PubMed1989

Phorbol ester transiently increases topoisomerase I mRNA levels in human skin fibroblasts.

Exposure of human skin fibroblasts to phorbol 12-myristate 13-acetate (PMA) results in a transient increase in the level of topoisomerase I mRNA. A maximal increase (about 10-fold) in the level of topoisomerase I mRNA was observed 3 h after adding 200 nM PMA, but a decrease to the basal level was observed within 12 h of PMA treatment. The lowest PMA concentration to give an observable induction of topoisomerase I gene expression was found to be 20 nM. In addition, the induction of topoisomerase I gene expression by 20 nM PMA pulse treatment for 10 min followed by incubation for an additional 3 h attained the same level of induction seen with 3 h of continuous exposure to 20 nM PMA. This observation suggests that once the signal for protein kinase C activation is transduced, continuous exposure to PMA is not necessary for the maximal effect. To gain insight into the mechanism by which PMA stimulates topoisomerase I gene expression, cells were treated with PMA, cycloheximide, and actinomycin D, either alone or in various combinations. The results show that actinomycin D, but not cycloheximide, specifically abolishes the stimulatory effect of PMA, suggesting that PMA affects topoisomerase I gene expression at the transcriptional level.

Binding, Competitive↗

PubMed1989

Studies of topoisomerase-specific antitumor drugs in human lymphocytes using rabbit antisera against recombinant human topoisomerase II polypeptide.

A complementary DNA fragment of the human DNA topoisomerase II gene was cloned into a T7 expression vector and overproduced in Escherichia coli. Rabbit polyclonal antibodies were raised against the recombinant topoisomerase II polypeptide which corresponds to the C-terminal one-third of human topoisomerase II polypeptide. Using the antiserum, DNA topoisomerase II levels were measured by immunoblotting human lymphocytes following phytohemagglutinin (PHA) stimulation. Our results showed that the intracellular topoisomerase II but not the topoisomerase I level increased in parallel with the entry of cells into proliferation. At least a 100-fold increase in topoisomerase II was observed at 50 h after PHA stimulation. As topoisomerase II levels increased upon PHA stimulation, DNA damage induced by teniposide (VM26) increased in parallel, as measured by both DNA synthesis inhibition and chromosomal aberrations. However, the damage induced by camptothecin also increased upon PHA stimulation, while the level of topoisomerase I remained relatively constant. Our results suggest that, in addition to cellular contents of topoisomerases, the state of cell proliferation is another important determinant of drug action.

Animals↗

PubMed1989

Recurrent fetal loss with circulating lupus anticoagulant: report of 2 cases.

Lupus anticoagulant (LAC), an autoantibody, in maternal circulation is responsible for a high incidence of fetal loss. We record 2 cases of recurrent fetal loss in association with LAC. The presence of LAC was diagnosed by prolonged activated partial thromboplastin time (aPTT), but was not correctable by dilution with normal plasma. During their subsequent pregnancies, these two women were treated with prednisolone and a low dose of aspirin (100 mg/day). Normal values of aPTT were achieved in both cases after treatment. Preeclampsia developed in one of the women, and a live premature infant was delivered by cesarean section. However, a successful term pregnancy was achieved in the other case. Corticosteroid and low-dose aspirin appear to improve fetal outcome in cases with LAC.

Abortion, Habitual↗

PubMed1989

Free alpha subunit of human chorionic gonadotropin in women with non-trophoblastic tumors.

Patterns of secretion of free alpha subunit in 242 women with non-trophoblastic tumors were studied. In 4 patients molecular forms of alpha subunit were investigated. In normal menstruating women, day to day fluctuations of alpha subunit (36 to 4871 ng/day) with a peak at midcycle were commonly observed. This makes measurement of the alpha subunit as a tumor marker difficult to interpret in this group of women. On the other hand, the secretion of alpha subunit in postmenopausal women was relatively stable (from 50 to 450 ng/day). Thus the incidence of elevated alpha subunit secretion (greater than 400 ng/day) in postmenopausal patients with non-trophoblastic tumors was as follows; cervical cancer (29.9%), ovarian cancer (50%), corpus cancer (37.5%), vulvar cancer (33.3%), lung cancer (53.3%), gastrointestinal tract cancer (80%). The elevation of the alpha subunit was unrelated to the histological type of cancer. Discordant secretion of hCG and its subunits were noted. The incidence of elevated hCG secretion (greater than 100 ng/day) for the same group of postmenopausal patients with non-trophoblastic tumors was 44.8% for cervical cancer, 100% for ovarian cancer, 62.5% for corpus cancer, 33.3% for vulvar cancer, 26.7% for lung cancer and 40% for gastrointestinal tract cancer. The incidence of isolated alpha subunit secretion in cervical cancer stages III and IV, lung cancer and gastrointestinal tract cancer (40-43%) was higher than that in other cancers (0-27%). For cervical cancer, the more advanced disease was associated with higher alpha subunit levels. The molecular forms of alpha subunit in 4 patients with non-trophoblastic tumors were studied by gel HPLC.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗

PubMed1989

Human chorionic gonadotropin and its subunits in pre-eclampsia.

The serum levels of hCG and its subunits were studied in 11 cases of pre-eclampsia (8 cases of severe pre-eclampsia and 3 cases of mild pre-eclampsia) and 72 normal pregnant women. The hCG (human chorionic gonadotropin) immunoactivity measured by H80 RIA (radioimmunoassay) and Sb6 RIA showed no significant difference between pre-eclampsia and normal pregnancy. This result suggests that no significant amount of free hCG-beta existed, since H80 RIA measured intact hCG but not hCG-beta, and Sb6 RIA measured both hCG and hCG-beta. Furthermore, from the result of elution behavior of gel HPLC (high performance liquid chromatography), hCG of pre-eclampsia and comparison of the Sb6 RIA/H80 RIA ratio between pre-eclampsia and normal pregnancy, it was evident that there was little amount of free hCG-beta secretion in pre-eclampsia as in normal pregnancy. However, the free hCG-alpha was significantly higher in severe pre-eclampsia, probably caused by placental dysfunction. In summary, free hCG-alpha is increased in pre-eclampsia, but its role as a marker of placental function in pre-eclampsia requires further investigation.

Chorionic Gonadotropin↗

PubMed1989

Hypertensive disorders in pregnancy: analysis of 110 cases.

One hundred and ten cases of hypertensive disorders in pregnancy were analyzed retrospectively. There were 16 cases of gestational hypertension, 36 cases of mild preeclampsia, 43 cases of severe preeclampsia, 6 cases of eclampsia, and 9 cases of chronic hypertension with superimposed severe preeclampsia. The principle of management was conservative in order to prolong pregnancy for patients remote from term. Corticosteroids were used to accelerate fetal lung maturity for patients with gestations of less than 36 weeks and magnesium sulfate was administered to prevent seizures. Fetal heart rate monitoring was done routinely and doppler blood flow velocity time wave form study of uterine and umbilical arteries was also performed in the latter part of the study. The cesarean section rate in gestational hypertension and mild preeclampsia was comparable to the general obstetric population in our institute (26.9% vs. 21.2%), but the rate of severe forms of the disease including severe preeclampsia, eclampsia, and chronic hypertension with superimposed severe preeclampsia was as high as 77.6%. Fetal distress was the main indication of section. There were 2 cases (6.9%) of mild respiratory distress syndrome, and all recovered uneventfully. The patients with severe forms of the disease had a higher incidence of small infants for gestational age (72%) and delivery at less than 36 weeks' gestation (48.2%). The corrected perinatal mortality rate was 5.4%. No maternal death was encountered. It was concluded that pregnancy could be prolonged in the interest of fetal lung maturity under meticulous maternal-fetal monitoring without endangering the mother.

Adolescent↗

PubMed1988

Human DNA topoisomerase I is encoded by a single-copy gene that maps to chromosome region 20q12-13.2.

cDNA clones of the human TOP1 gene encoding DNA topoisomerase I (EC 5.99.1.2) have been obtained by immunochemical screening of phage lambda libraries expressing human cDNA segments, using rabbit antibodies raised against purified HeLa DNA topoisomerase I. Hybridization patterns between the cloned cDNA sequences and human cellular DNA and cytoplasmic mRNAs indicate that human TOP1 is a single-copy gene. The chromosomal location of the gene has been mapped to the long arm of chromosome 20, in the region q12-13.2, by hybridization of a radioactively labeled TOP1 cDNA probe to human metaphase chromosomes and to a panel of rodent-human somatic hybrids retaining overlapping subsets of human chromosomes.

Animals↗