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H S Liu

Publications and source records attributed to H S Liu.

At least 37 records · Page 2Linked to original sources
PubMed2000

[The applied anatomy of transposition of the distal dorsal ulna bone flap pedicled with dorsal metacarpal artery].

OBJECTIVE: To investigate the anatomic basis for transposition of the distal dorsal ulna bone flap pedicled with dorsal metacarpal artery to repair the defect of the 3rd or 4th and 5th metacarpal bone head. METHODS: In 30 adult cadaveric upper limbs, the branches and constitutions of the dorsal carpal arterial networks were observed. RESULTS: The dorsal carpal arterial networks were consisted of the dorsal carpal branches of ulnar and radial arteries, the terminal branches of posterior interosseous artery and the dorsal carpal branch of anterior interosseous artery, and then the 2nd, 3rd, 4th dorsal metacarpal branches were originated from the networks. The dorsal metacarpal branches were anastomosed with the deep branches of deep palmar arch to constitute the dorsal metacarpal artery. CONCLUSION: Transposition of the distal dorsal ulna bone flap pedicled with the 3rd, 4th dorsal metacarpal arteries can be used in repairing the defect of 3rd, 4th and 5th metacarpal bone head.

Adult↗
PubMed1999

Favorable clinical outcome of cervical cancers infected with human papilloma virus type 58 and related types.

To determine whether the status of human-papillomavirus (HPV) infection affects the clinical outcome of cervical carcinoma (CC), HPV genotype was prospectively determined in 94 consecutive CC cases subsequently followed for a median duration of 37.5 months. With a consensus PCR-RFLP method of HPV genotyping, 81 (86.2%) cancers were positive for HPV DNA. They were classified, according to the phylogenic similarities, into HPV-16-related (type 16, n = 45; type 31, n = 2), HPV-58-related (type 58, n = 17; type 33, n = 3; type 52, n = 2) and HPV-18-related (type 18, n = 8; type 68, n = 1) groups, and analyzed in relation to clinical outcome. The following results were observed: (i) Type-58-related HPVs were more prevalent in the old age (older than the median age of 52) group than in the young age group (41% vs. 14.6%, p = 0.045); (ii) 63% (5/8) of patients with advanced stages (III and IV) were HPV-negative, a figure much higher than that (9.3%, 8/84) of patients with early stages (stage I and II) (p = 0.002); (iii) the occurrence of adenocarcinoma or adenosquamous carcinoma was higher in the HPV-18-related group (50%) than in the HPV-16-related (33.3%) or the HPV-58-related (16.7%) groups (p = 0.024); (iv) the status of lymph-node metastasis and tumor grade did not correlate with HPV status; (v) 5-year survival rates were 90.2%, 80% and 74% for HPV-58-, HPV-16- and HPV-18-related groups, respectively (p = 0.03, after adjustment for tumor stage); (vi) in comparison with the HPV-16-related group, the relative risk of death in the HPV-58- and the HPV-18-related groups were 0.32 [95% CI, 0.07-1.49] and 1.87 [0.36-14.9] respectively. HPV genotype appears to affect the clinical behavior and outcome of cervical cancer. HPV-58-related types are prevalent in the older population, and appear to confer a favorable prognosis. Int. J. Cancer (Pred. Oncol.) 84:553-557, 1999.

Adult↗
PubMed1999

Bad overexpression sensitizes NIH/3T3 cells to undergo apoptosis which involves caspase activation and ERK inactivation.

The effect of Bad overexpression on apoptosis was demonstrated by a mouse Bad transgene stably expressed in NIH/3T3 cells. The cells overexpressing Bad treated with either serum starvation or ceramide showed apoptotic characteristics evident at 18 and 8 h, respectively. Whether serum deprivation and ceramide utilize a common death pathway requires further investigation. The time for the first apoptosis detection was shortened to 2 h and was prominent at 4 h, while above that time cells were maintained under serum-depleted conditions in the presence of ceramide (40 microM). Further investigation revealed that the activity of caspase-3 (CPP32) was elevated after ceramide treatment in Bad-transfected cells compared to that of the cells without Bad transfection, indicating the involvement of caspase cascade. Furthermore, the Bad-transfected cells showed reduced phosphorylation of extracellular signal-regulated kinase (ERK). Taken together, we hypothesize that Bad-overexpressing NIH/3T3 cells in the presence of ceramide undergo apoptosis by activating caspase cascade. Simultaneously, the cell survival pathway was blocked possibly by inactivation of the MAPK pathway such as the down-regulation of ERK.

3T3 Cells↗
PubMed1999

Is green fluorescent protein toxic to the living cells?

Green fluorescent protein (GFP) has become more popular to be used as a living marker for positively transfected clones in many studies. To establish stable cell lines constitutively expressing GFP, three GFPs expressed from plasmid pBIEGFP, pSG5GFP, and pRSGFP were introduced into NIH/3T3, BHK-21, Huh-7, and HepG2 cells. All the GFPs we used are the mutant forms of a common wild phenotype. The pBIEGFP expressed enhanced GFP (EGFP). The pRSGFP and pSG5GFP expressed red shift GFP (RSGFP). The RSGFP gene in pSG5GFP was driven by a strong SV40 promoter and showed at least 20-fold higher RSGFP expression by western blot analysis. Despite of the variation in the levels of GFP expression, many GFP expressing cells contracted, rounded-up, and died, which was confirmed by decreasing luciferase activity. CPP32 activity and flow cytometric analyses further demonstrate that cells expressing GFP underwent apoptosis. Our observation is contradictory to other reports that GFP is nontoxic to the cells. Most importantly, this paper shows for the first time the link between expression of GFP and induction of apoptosis. This finding should promote studies of GFP cytotoxicity and attempts to isolate new non-toxic mutants of GFP.

Animals↗
PubMed1999

Selective activation of Ha-ras(val12) oncogene increases susceptibilityof NIH/3T3 cells to TNF-alpha.

This is the first report demonstrating that NIH/3T3 fibroblasts utilize the Raf-1/MAPK pathway to sensitize themselves to tumor necrosis factor-alpha (TNF-alpha) cytotoxicity under Ha-rasVal12 oncogene-overexpressed conditions. This paper clearly shows that the sensitivity of NIH/3T3 cells to TNF-alpha cytotoxicity positively correlated with the expression level of activated Ha-ras transgene, which was manipulated either positively by isopropyl-beta-d-thiogalactoside (IPTG) induction or negatively by a ribozyme or a dominant negative Ras suppression. Further analysis revealed that after TNF-alpha treatment, Ha-ras-overexpressed transformants underwent apoptosis. Overexpression of dominant negative Raf-1, Rac1, or RhoA in the Ha-ras transformants clarified that among these factors, only dominant negative Raf-1 could reverse the cell sensitivity to TNF-alpha, indicating that Raf-1, as a proapoptotic factor, indeed participates in TNF-alpha cytotoxicity. The anti-apoptotic roles of Bcl-2 and PI(3) kinase are also demonstrated by the Ha-ras transformants which became more resistant to TNF-alpha while overexpressing Bcl-2 or the activated p110 catalytic subunit. The analyses of the cell cycle and nuclear transcription factor activities revealed that TNF-alpha treatment caused the Ha-ras overexpressed transformants to shift from S to G0/G1 phase and increased the responses of AP-1, c-fos, and c-myc. Taken together, we suggest that the possible action of Ha-ras overexpression to sensitize TNF-alpha-treated fibroblasts is predominantly through the Ras/Raf-1/MAPK pathway to increase the responses of AP-1, c-fos, and c-myc, which are possibly involved in the aberration of cell cycle machinery, and subsequently to turn on the death program.

Apoptosis↗
PubMed1999

Frequent aberration of the transforming growth factor-beta receptor II gene in cell lines but no apparent mutation in pre-invasive and invasive carcinomas of the uterine cervix.

The type II transforming growth factor-beta (TGF-beta) receptor (RII) gene located at 3p22 plays an important role in regulating growth and differentiation of epithelium, including that of the uterine cervix. Loss-of-function mutations of RII have frequently been found in gastrointestinal cancers, with a replication-error (RER) phenotype characterized by the presence of microsatellite instability (MI). In this study, genomic PCR, SSCP and DNA sequencing were conducted to investigate the coding sequences of the RII gene in cell lines (n = 5) and tissues (n = 15) of squamous carcinomas of the uterine cervix. Intragenic deletions were noted in 2 of 5 cervical-cancer cell lines (ME180 and HeLa cells). However, no mutation, other than DNA polymorphisms, was found in 15 cervical cancers with either alleleic loss at 3p22 (n = 11) or MI (n = 4). Further analysis of squamous intraepithelial lesions (SIL) with (n = 12) or without (n = 4) MI for the (A)10 change, a prototypic mutation found in over 90% of RER-positive colon cancers, also showed no aberration. Our study concludes that the RII gene is frequently disrupted in cervical-cancer cell lines, but is rarely mutated in CC and SIL tissues, including those showing MI or alleleic loss at 3p22. The underlined mechanism of genomic instability in CC and SIL may thus differ from that of colorectal cancer. The allelic loss at 3p22-24 in CC does not involve the coding sequence of the RII gene. The non-coding sequence of RII or an unidentified gene may be responsible for it.

Carcinoma, Squamous Cell↗
PubMed1999

Monoclonality and surface lesion-specific microsatellite alterations in premalignant and malignant neoplasia of uterine cervix: a local field effect of genomic instability and clonal evolution.

Invasive squamous carcinoma of the uterine cervix (CC) arises from sequential progression of low-grade (L) and high-grade (H) squamous intraepithelial lesions (SILs). In clinical observations, these lesions are frequently found as synchronous multiple foci. The nature and evolutionary mechanism of these lesions are largely unknown. We have performed allelotyping of three 3p markers (at 3p14, 3p22-24, and 3p25) on 22 LSILs and 15 HSILs microdissected from patients with multiple (n = 21) or uniform (n = 6) cervical lesions. The results were analyzed together with our previous allelotyping of 57 deeply invasive CCs. Loss of heterozygosity at one of the three markers was observed in 23%, 27%, and 31 % of LSILs, HSILs, and CCs, respectively. Frequent and early allelic loss was noted (in 30% of LSILs and 50% of HSILs) at 3p14, which may harbor tumor suppressor genes involved in early stages of cervical carcinogenesis. A high frequency of microsatellite alteration (MA) was found in LSIL (41%) and HSIL (67%) but not in CC (5.3%). In particular, MA was more frequently found in low-grade lesions in association with invasive cancers (75%, 6/8) than in those associated with SILs (29%, 4/14) (P < 0.05). Together with the finding of a monoclonal origin of premalignant and malignant cervical lesions, the present results allow us to propose a model of local field effect of genomic instability that progressively affects the clonal evolution of SIL of uterine cervix.

Carcinoma in Situ↗
PubMed1999

Intracervical misoprostol as an effective method of labor induction at term.

OBJECTS: The purpose of this study was to evaluate the safety and effectiveness of intracervical misoprostol for the induction of labor at term. METHODS: Eighty-nine term pregnancies requiring induction of labor were treated intracervically with 50 microg of misoprostol. The dose was repeated every 4 h until adequate uterine contraction and cervical dilatation were achieved. Status of cervical ripening, uterine contraction, cervical dilatation, labor course and side effects were recorded and analyzed. RESULTS: Among the 89 patients, 58 had an unfavorable cervix (Bishop score < or = 4) and 31 had a favorable cervix (Bishop score > 4). Labor was successfully induced in all cases, most (93.3%) of which required a single dose of misoprostol. Seventy-two patients (81%) proceeded to spontaneous vaginal delivery, and 61 (85%) deliveries were achieved within 12 h. The other 17 cases received cesarean delivery with indications of fetopelvic disproportion (six cases), failure of induction (seven cases) and acute fetal distress (four cases). The mean duration from induction to regular uterine contraction and to delivery was 483+/-537 min and 79.2+/-38.2 min, respectively, with no significant difference between the two groups with differing status of cervical ripening. Complications of uterine contraction, including tachysystole (15 cases), hypertonus (one case) and hyperstimulation (10 cases) were more common in the group of unfavorable cervix (45%) than that of favorable cervix (23%) (P < 0.05). CONCLUSION: In addition to the oral and intravaginal routes of administration, intracervical misoprostol at a single dose of 50 microg appears to be an effective method for induction of labor at term, but caution should be taken with cases with unfavorable cervix.

Abortifacient Agents, Nonsteroidal↗
PubMed1999

Fetal Doppler hemodynamic changes in spontaneous versus prostaglandin E1-induced active labor.

BACKGROUND: To assess fetal hemodynamic changes before and during active labor, either spontaneous or prostaglandin E1 (PGE1)-induced labor. MATERIALS AND METHODS: This is a prospective longitudinal study and a cohort of 49 healthy women at 37-41+ weeks gestation without signs of fetal distress was investigated until in labor. One group of 23 healthy women had spontaneous active labor, the second group of 26 women was in active labor induced by an intra-cervical administration of PGE1 for elective induction. Blood flow waveform indices (S/D ratio, RI, PI) were assessed by pulsed Doppler ultrasonography from the umbilical artery (UA) and fetal middle cerebral artery (MCA) before and in labor. Both groups were compared for the waveform indices and perinatal outcome including duration of labor, meconium stain, baby sex, birthweight, UA blood gas measurements at delivery, Apgar's scores, prolonged nursery stay (> or =5 days), and NICU admission. RESULTS: Demographic data of the two groups were comparable. During spontaneous active labor, the S/D ratio and RI became significantly decreased in the UA (p<0.05) and the three wave-form indices were decreased more in the MCA (p<0.01, 0.005, 0.05, respectively) compared with those measured before labor. During PGE1-induced active labor, all the waveform indices were not significantly decreased in either the UA or the MCA. The occurrence of abnormal UA blood gas values was significantly more in the PGE1-induced group than in the spontaneous labor group (23.1% v.s. 4.3%; p<0.05). No other adverse perinatal outcomes were observed in either group. CONCLUSIONS: Decreasing impedance in both the UA and MCA during spontaneous labor is a physiological fetal adaptation to labor to prevent fetal cerebral hypoxia by maintaining adequate brain blood flow during normal parturition. This fetal adaptation phenomenon was not observed in the group of PGE1-induced labor with the result of a high incidence of abnormal UA blood gas values.

Adult↗
PubMed1998

Ha-rasVal12 oncogene increases susceptibility of NIH/3T3 cells to lovastatin.

This study demonstrates that Ha-rasVal12 oncogene overexpression sensitizes NIH/3T3 fibroblasts to lovastatin (LOV) cytotoxicity. This sensitization is through apoptosis, which was characterized by increasing CPP32 (caspase-3) activity and DNA fragmentation. Bcl-2 overexpression increased the resistance of the Ha-ras transformants to LOV and rescued the cells from apoptosis, further confirming that the LOV-sensitive cells died of apoptosis. Further analysis showed that Ha-ras activity inversely correlated with WAF1 activity. LOV treatment suppressed Ha-ras activity but induced WAF1 activity and disrupted the cell population in G0/G1 and S phases. The Ha-ras transformants expressing either dominant negative RasAsn17 or Raf-1CB4 showed reverted susceptibility to LOV. These data confirm the involvement of Ras and demonstrate that Raf-1 signalling is required for LOV-induced cell death. Taken together, the possible action of LOV-induced apoptosis is through suppressing Ha-ras activity and increasing WAF1 activity, which alters cell cycle progression and finally activates suppressed apoptotic pathway in a Fas/Fas-L- and p53-independent fashion.

3T3 Cells↗
PubMed1998

Neoadjuvant chemotherapy followed by radiotherapy should not be a standard approach for locally advanced cervical cancer.

PURPOSE: To investigate the role of neoadjuvant chemotherapy followed by radiotherapy in locally advanced cervical cancer. METHODS AND MATERIALS: This study cites all known literature on the subject in the English language. Articles were selected for analysis by MEDLINE and CANCERLINE computer searches. In Phase II trials, the response rates of some selective series were analyzed. However, This article will specially emphasize the result of all Phase III randomized trials. RESULTS: Several investigators did obtain promising results from Phase II trials of neoadjuvant chemotherapy, mostly cisplatin-based combinations, followed by radiotherapy. However, most Phase III trials failed to demonstrate any benefit in terms of loco-regional relapse and/or survival by up-front chemotherapy. CONCLUSION: The role of neoadjuvant chemotherapy remains to be defined, and the search for more active new agents must be continued. The neoadjuvant setting is still experimental and could not be recommended as a standard treatment at the present.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

HPV-associated cervical cancers show frequent allelic loss at 3p14 but no apparent aberration of FHIT mRNA.

The genetic aberration involved in the loss of heterozygosity (LOH) at 3p14 has recently been attributed to the disruption of the FHIT gene in many cancers. This study analyzed HPV DNA and allelic status of 5 microsatellite markers spaning 3p13-3p25 in 57 cases of cervical cancer. With no homozygous deletion found in any case, a 39% overall frequency of LOH was noted. The presence of tumorigenic HPV DNA (91%) did not correlate with the allelic loss at any marker, including THRB (3p22-24) and D3S1228 (3p14) which were found with high LOH rates of 43% (12/28) and 37% (11/30), respectively. Further analysis of FHIT mRNA in 29 cancers by reverse transcription (RT)-PCR showed a full-length transcript in all cases. However, additional minor transcripts were occasionally observed in cancer tissues (9/29) as well as in normal tissues (12/31) by nested PCR of the RT products. Sequence analysis of these transcripts showed exclusive internal exon deletions, suggesting a source of minor splicing variants. No apparent mutation of the mRNA sequences was found in 8 transcripts examined, except for a silent polymorphism and a site of alternative splicing. The results suggest that, although frequently reported to be abrogated in several cancers, the mRNA of FHIT remains intact in cervical cancer. Other genes closely linked to FHIT may be responsible for frequent LOH at 3p14 observed in cervical cancer.

Acid Anhydride Hydrolases↗
PubMed1998

Using 2-step PCR and restriction endonuclease digestion to detect K-ras mutation in paraffin-embedded tissues: is it reliable?

In this study, we detected the existence of both wild type and mutant K-ras DNA on the cutting board and in the solutions for tissue processing in our pathology laboratory. The detection rate of K-ras mutant DNA inversely correlated with the frequency of the solution changed, implying that DNA contaminant including K-ras mutant may be accumulated while increasing specimens were processed. The exact routes of contamination during tissue processing remain to be determined. Nevertheless, this study unveils the possibility of DNA contamination in the laboratory that can be amplified by PCR analysis, and precaution should be taken while we interpret our PCR data from paraffin-embedded specimens. The work also highlights the necessity of contamination control procedures, including specific laboratory construction, environmental control, and strict hygiene standards for laboratory equipment and personnel. Moreover, fresh specimens seem more reliable than archival materials for PCR diagnosis.

DNA Restriction Enzymes↗
PubMed1998

Second and early third trimester pregnancy termination by extra-amniotic balloon and intracervical PGE2.

OBJECTIVE: The aim of the study was to investigate the efficacy and safety of an alternative modality using extra-amniotic balloon and intracervical prostaglandin (PG) E2 for termination of second and early third trimester pregnancies. METHOD: Thirty-three pregnant women scheduled for legal termination of pregnancy at 15-32 weeks' gestation were included in the study. Each case received extra-amniotic balloon containing 500-800 ml normal saline and two PGE2 tablets inserted into the cervical canal. RESULTS: All 33 patients achieved a successful termination. The mean induction-to-abortion interval was 12.85 h. There was no significant difference in induction-to-abortion interval between second trimester group and third trimester group. However, the mean duration of balloon distention was longer in the second trimester group. There were no severe complications. CONCLUSION: The combined use of extra-amniotic balloon and intracervical PGE2 tablets is effective, safe and convenient for termination of second and early third trimester pregnancy.

Abortion, Legal↗
PubMed1998

Thromboxane and prostacyclin in maternal and fetal circulation in pre-eclampsia.

OBJECTIVES: A major pathophysiologic change of pre-eclampsia has been attributed to the overproduction of thromboxane A2 (TXA2) mainly from activated platelets. On the other hand, increased biosynthesis of TXA2 has also been reported from preeclamptic placentas. The systemic role of these different sources of TXA2 has not been clarified. The purpose of this study is to define the changes of TXA2 and the antagonizing prostacyclin (PC) in maternal and fetal circulations. METHODS: The stable metabolites of TXA2 and PC [Thromboxine B2 (TXB2) and 6-keto-prostaglandin F1alpha (6-keto-PGF1alpha), respectively] in the cord and maternal blood of nine patients with pre-eclampsia and nine normal parturients were measured by radioimmunoassay. RESULT: In normal pregnancy, the cord blood contained much higher TXB2 (1697+/-898 vs. 267+/-128 ng/ml, P < 0.01) and 6-keto-PGF1alpha (266+/-263 vs. 12.5+/-3.9 ng/ml, P < 0.05) levels than the maternal blood. In the preeclamptic state, a marked increase of TXB2 was noted in both maternal and cord blood, reaching levels which were significantly higher than during normal pregnancy (2995+/-1103 vs. 267+/-128 ng/ml in maternal blood, P < 0.0001, and 3197+/-1288 vs. 1697+/-898 ng/ml in cord blood, P < 0.005). A less significant increase in 6-keto-PGF1alpha (134+/-10.8 vs. 12.5+/-3.9 ng/ml, P < 0.05) was also noted in the maternal blood. Moreover, the level of TXB2 correlated with the diastolic blood pressure of preeclamptic patients before and after delivery. CONCLUSION: The results suggest an abundant source of eicosanoids in the feto-placental circulation, which does not readily cross the placental barrier. In pregnancy complicated with pre-eclampsia, thromboxane level of both fetal and maternal circulations are markedly increased, which may be responsible for the pathophysiologic changes. The lack of adverse systemic effects on the fetus highlights a placental source of TXA2 of transient bioactivity which is rapidly hydrolyzed to non-active TXB2. Federation of Gynecology and Obstetrics

Adult↗
PubMed1998

Extra-amniotic balloon with PGE2 versus extra-ovular Foley catheter with PGF2alpha in mid-trimester pregnancy termination.

OBJECTIVE: The objective of this study was to compare the efficacy and side effects of two methods of mid-trimester labor induction, extra-amniotic balloon with intracervical prostaglandin (PG) E2 (0.5 mg x 2) vs. extra-ovular Foley catheter with intrauterine PGF2alpha (1 mg/h x6). METHODS: A cohort of 32 and 36 cases indicated for mid-trimester termination was enrolled and managed with extra-amniotic balloon and extra-ovular Foley catheter methods, respectively. Outcomes of induction-to-delivery interval, induction failure, and occurrence of side effects were assessed. RESULTS: There were no statistical differences in maternal age, parity, gestational age or fetal birth weight between the two groups. Compared with the extra-ovular Foley catheter with PGF2alpha group, the induction-to-delivery interval was significantly shorter in the extra-amniotic balloon plus PGE2 group. There was no significant difference in side effects and major complications developed in either groups. CONCLUSIONS: The extra-amniotic balloon with intracervical PGE2 is more efficient in reducing the induction-to-delivery interval for termination of mid-trimester pregnancies than the extra-ovular Foley catheter with intrauterine PGF2alpha.

Abortion, Induced↗
PubMed1998

Potential value of urinary intercellular adhesion molecule-1 determination in patients with bladder cancer.

OBJECTIVE: Intercellular adhesion molecule-1 (ICAM-1) is known to play a role in immunity against bladder cancer and can be detected in the supernatants of cultured bladder cancer cells that constitutively express ICAM-1. This study was performed to examine the relevance of the ICAM-1 urine test in patients with bladder cancer. METHODS: A total of 53 patients with bladder carcinoma, 35 with history of bladder cancer, and 30 normal control subjects were included in this analysis. Urinary ICAM-1 (ulCAM-1) levels were measured by immunoassay and corrected for hydration status. RESULTS: Levels of ulCAM-1 were significantly elevated in patients with bladder cancer or those at tumor-free status compared with normal control subjects (P=0.001). However, there was no apparent difference between the two groups of urothelial disorders (P >0.1). ulCAM-1 did not correlate with clinicopathologic variables of bladder cancer or patient outcome (P >0.1). Six patients at tumor-free status had multiple ulCAM-1 determinations during the study period. Three of these 6 patients had elevated ulCAM-1 levels and proved to have recurrent tumors; 3 of the 6 had stable ulCAM-1 levels and were still free of disease. CONCLUSIONS: Our results suggest that urinary excretion of ICAM-1 is elevated in the early stage of bladder carcinogenesis, but is independent of biologic properties of bladder cancer. Serial monitoring of ulCAM-1 may be helpful in selecting patients who are at risk of tumor recurrence.

Adult↗