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Biomedical subjects

C J Liu

Publications and source records attributed to C J Liu.

At least 19 recordsLinked to original sources
PubMed1999

The interferon-inducible nucleolar p204 protein binds the ribosomal RNA-specific UBF1 transcription factor and inhibits ribosomal RNA transcription.

p204, a member of the interferon-inducible p200 family of murine proteins, is primarily nucleolar. We generated cell lines in which p204 was inducible by muristerone. This induction resulted in retardation of cell proliferation and inhibition of rRNA transcription in vivo. Interferon treatment, resulting in p204 induction and retardation of proliferation, also caused inhibition of rRNA transcription in vivo. p204 also inhibited rRNA transcription in vitro. This inhibition was overcome by addition of UBF1, the rRNA-specific transcription factor. A direct interaction between p204 and UBF1 was revealed in vitro in pull-down assays, and in vivo by co-immunoprecipitation from cell extracts. UBF1 bound strongly to at least two regions of p204: the N-terminal segment linked to the conserved 200 amino acid a segment, and the conserved 200 amino acid b segment. Cleavage of the a or b segments into two segments (encoded by single exons) resulted in a strong decrease or loss of binding. The inhibition of rRNA transcription by p204 may be due to the inhibition by p204 of the specific DNA binding of UBF1. This was revealed in electrophoretic mobility shift, magnetic bead and footprinting assays. Thus, p204 serves as a mediator of the inhibition of rRNA transcription by interferon.

Animals↗
PubMed1999

Coordinated accumulation of (+)-delta-cadinene synthase mRNAs and gossypol in developing seeds of Gossypium hirsutum and a new member of the cad1 family from G. arboreum.

A new member of the (+)-delta-cadinene synthase (CAD1) family was isolated from a Gossypium arboreum cDNA library. This cDNA encodes a protein that showed 97.3%, 96.9%, and 79.2% sequence identities with the proteins encoded by previously isolated cDNAs of cad1-C1, cad1-C14, and cad1-A, respectively. It may be grouped into the cad1-C subfamily as cad1-C2. Seeds of a glanded cotton cultivar, G. hirsutum cv. Sumian-6, were collected at different intervals during maturation, and the cad1 mRNA levels were analyzed by quantitative RT-PCR. The transcripts could be detected in seeds of 27 DPA (days postanthesis) and increased dramatically along with the seed maturation, which coordinated with an increase in sesquiterpene cyclase activities and subsequently the accumulation of gossypol. The transcription level detected with primers specific to cad1-C (including at least C1, C14, and cdn1) was higher than that detected with primers specific to cad1-A, and mRNA was detected also with cad1-C2-specific primers. This investigation indicates that, in developing seeds of the glanded cotton cultivar, genes of both the CAD1-C and CAD1-A subfamilies are expressed and there is an active biosynthesis of cadinene-type sesquiterpenes.

Amino Acid Sequence↗
PubMed1999

Minimal role of GB virus-C/hepatitis G virus in fulminant and subfulminant hepatitis in Taiwan.

BACKGROUND: The role of GB virus-C/hepatitis G virus (GBV-C/HGV) in fulminant hepatitis (FH) and subfulminant hepatitis (SFH) remains unclear. METHODS: Thirty-two FH or SFH patients, with adequate clinical information and serum specimens, were studied. Serum samples were tested for hepatitis markers and genomes of hepatitis A-E viruses, as well as GBV-C/HGV. RESULTS: Of the cases of FH/SFH studied, one (3%) was caused by anti-tuberculosis agents, 26 (81%) had hepatotropic virus infection, and five (16%) had no identifiable cause. Of the 26 patients with hepatotropic virus infection, five had acute hepatitis B infection (one with acute hepatitis D virus (HDV) co-infection), one had acute hepatitis C infection, 16 were hepatitis B surface antigen carriers with reactivation or superimposed by unidentified agent(s) (two had triple virus infections), three were hepatitis B carriers with HDV superinfection, and one had GBV-C/HGV infection in addition to exposure to halothane. GBV-C/HGV-RNA was detected in only three of 32 patients (9%) and all had a history of blood transfusion or co-existing causative factors. Of the 26 patients with hepatotropic virus infection, 18 were tested for antibodies against GBV-C/HGV envelope protein and seven were reactive, suggesting past infection. CONCLUSIONS: The role of GBV-C/HGV in causing FH and SFH is minimal in Taiwan and HBV infection remains the major aetiology. These findings also suggest the existence of as yet unrecognized agents, responsible for such catastrophic illnesses.

Adult↗
PubMed1999

Evaluation of ocular arterial changes in glaucoma with color Doppler ultrasonography.

The purpose of this study was to evaluate hemodynamic changes of the retrobulbar vasculature caused by different intraocular pressures with color Doppler ultrasonography. Fifty normal eyes in 25 patients, 13 patients with normal tension glaucoma, and 19 patients with acute glaucoma and increased intraocular pressure (greater than 30 mm Hg) were enrolled in this study. In 15 of 19 patients with acute glaucoma patients, follow-up color Doppler ultrasonography was also undertaken after laser peripheral iridectomy when the intraocular pressure had returned to normal. The peak systolic velocity, end diastolic velocity, resistive index, time average maximum velocity, and pulsatility index were compared in different vessels, including the central retinal artery, lateral posterior ciliary artery, medial posterior ciliary artery, and ophthalmic artery in each orbit. The peak systolic velocity, end diastolic velocity, and time average maximum velocity of the central retinal artery were significantly lower (P<0.01) in acute glaucoma patients than in the control group. The resistive index and pulsatility index of the central retinal artery were significantly higher (P<0.01) in acute glaucoma patients than in the control group. The end diastolic velocity of the lateral and medial posterior ciliary arteries was significantly lower in patients with acute glaucoma than in the control group, and the resistive index and pulsatility index of both of these arteries were significantly higher (P<0.001) in patients with acute glaucoma than in the control group. However, no statistical significantly differences were found in the peak systolic velocity or time average maximum velocity in either of the posterior ciliary arteries; similarly, no statistically significant differences were noted in any of the parameters in the ophthalmic artery between the control group and the group with acute glaucoma. The pulsatility index of the central retinal artery and of the lateral and medial posterior ciliary arteries was significantly lower (P<0.01) in acute glaucoma patients after laser therapy than in acute glaucoma patients before laser therapy. The resistive index of both posterior ciliary arteries was also significantly lower (P<0.004) in acute glaucoma patients after laser therapy than before laser therapy. All parameters for all vessels examined among the normal subjects, the patients with normal tension glaucoma, and the patients with acute glaucoma after laser therapy when the intraocular pressure had returned to normal showed no statistically significant differences. Color Doppler ultrasonography is a good modality for both imaging and studying the hemodynamics of the perioptic nerve vessels.

Aged↗
PubMed1998

Efficacy and safety of cefepime treatment in Chinese patients with severe bacterial infections: in comparison with ceftazidime treatment.

An open label, randomized comparative study was conducted to evaluate the safety and efficacy of cefepime, in comparison with ceftazidime, in the treatment of adult hospitalized Chinese patients with severe bacterial infections. Forty patients with severe infections including septicemia, urinary tract infection and bacterial pneumonia were randomly assigned to receive treatment with cefepime (2 g intravenously every 12 h) or ceftazidime (2 g intravenously every 8 h). The cefepime group (20 evaluable patients) and ceftazidime group (16 evaluable patients) were comparable with respect to age, sex, underlying diseases and distribution of infection type. In both groups urinary tract infection was the most common type of infection and Escherichia coli was the most common etiologic microorganism. The rates of satisfactory clinical response were similar in the cefepime and ceftazidime groups (95 versus 93.7%; 95% confidence interval: -0.14 - 0.17, P = 0.87). The bacteriological response rates of the cefepime and ceftazidime groups did not differ significantly (88.9 versus 85.7%; 95% confidence interval: -0.30 - 0.36, P = 0.85). Both cefepime and ceftazidime were well tolerated, with similar incidence of side effects. The results of this study suggest that cefepime is as safe and effective as ceftazidime for the treatment of serious infections in adult hospitalized Chinese patients.

Asian People↗
PubMed1998

Involvement of tyrosine phosphorylation of p185(c-erbB2/neu) in tumorigenicity induced by X-rays and the neu oncogene in human breast epithelial cells.

Ionizing radiation is the exogenous agent best proven to induce breast cancer. c-erbB2/neu amplification and overexpression are known to occur in breast cancer and are correlated with aggressive tumor growth and poor prognosis. We have developed simian virus 40-immortalized cell lines from normal human breast epithelial cells (HBECs) with luminal and stem-cell characteristics. In this study, we examined whether x-rays and a mutated neu oncogene are capable of inducing tumorigenicity in these cells. The results indicated that x-rays were effective in converting immortal non-tumorigenic HBECs to weakly tumorigenic cells that then could be transformed to highly tumorigenic cells by the neu oncogene. The in vitro growth of these tumorigenic cells was significantly faster than that of the parental non-tumorigenic cells in growth factor- and hormone-supplemented or -depleted media. The neu oncogene, however, had no tumorigenic effect on immortal non-tumorigenic cells. The expression of p185(c-erb82/neu) was elevated in neu-transduced immortal or weakly tumorigenic cell lines. However, only in the latter was p185(c-erbB2/neu) found to be phosphorylated at tyrosine residues. Thus, x-rays appear to induce a genetic alteration that confers weak tumorigenicity on immortal HBECs and interacts with p185(c-erbB2/neu) directly or indirectly to give rise to fast-growing tumors.

Animals↗
PubMed1998

Bacteremia and fungemia in patients with advanced human immunodeficiency virus (HIV) infection in Taiwan.

To understand the etiology and clinical outcome of bacterial and fungal sepsis in patients with advanced human immunodeficiency virus (HIV) infection in Taiwan, we conducted a prospective study of nonmycobacterial bacteremia and fungemia in HIV-infected patients with fever who were admitted to a university hospital in Taiwan during a 42-month period. Of 210 patients, 41 (19.5%) had a total of 52 episodes of sepsis due to nonmycobacterial bacteria or fungi, or both (15.5% of 336 episodes of fever). All but one patient had acquired immunodeficiency syndrome (AIDS), and the mean CD4 lymphocyte count was 29/microL (range, 0-321/microL). A total of 57 pathogens (39 bacteria and 18 fungi) were isolated from blood; polymicrobial sepsis due to both bacteria and fungi occurred in four episodes. Nontyphoid Salmonella (NTS) was the most common cause of community-acquired bacteremia (24/30, 80%). Staphylococcus aureus bacteremia was diagnosed in three episodes while Streptococcus pneumoniae bacteremia was found in only one. Cryptococcus neoformans was the most common cause of fungemia and was responsible for 12 episodes, while fungemia due to Penicillium marneffei and Histoplasma capsulatum, two emerging fungi in Taiwan, were diagnosed in four cases and one case, respectively. Nine episodes, eight of bacteremia and one of candidemia, were nosocomial. The overall in-hospital mortality was 29%, and nosocomial sepsis was associated with a higher mortality rate (56%, p = 0.02). The mean duration of survival after recovery from initial sepsis was 426 days. We conclude that NTS bacteremia was the most common cause of sepsis in patients with advanced HIV infection in Taiwan and clinicians caring for such patients should watch for emerging fungal infections. Nosocomial sepsis was associated with a high mortality rate. The mean survival duration after recovery from sepsis of our patients was short.

AIDS-Related Opportunistic Infections↗
PubMed1997

2-hydroxyethyl methacrylate-terminated polyurethane/polyurethane interpenetrating polymer networks.

The interpenetrating polymer networks (INPs) of polyurethane (PU) and 2-hydroxyethyl methacrylate (MEHA)-terminated polyurethane (HPU) were prepared by solution polymerization. PU prepolymer was synthesized from 4,4-diphenyl methane diisocyanate (MDI) and poly(propylene oxide) glycol (PPG). HPU prepolymer was synthesized from MDI, poly(tetramethylene oxide) glycol and HEMA. Dynamic mechanical analysis showed that the resultant IPN membranes have good compatibility between their constituents. As the HPU content increased, the tensile strength of the IPNs first increased and then decreased. For the highest tensile strength, the optimum HPU content was about 25 wt %. The value of surface tension of IPNs varied from 44.4 to 50.5 dyne/cm, and polarity ranged from 0.59 to 0.91. The relative index of platelet adhesion (RIPA) of the IPN membranes was measured by the dynamic thrombosis test at constant shaking speed and temperature. By the criteria of this test, the IPN membranes with HPU content of about 25 wt% to the minimum platelet adhesion. When measured by the angular dependent ESCA technique on the surface of IPN samples, the variation in the RIPA correlated to the change in the surface soft segment to hard segment ratio. Higher HPU content resulted in more migration of soft segments toward the surface. The platelet adhesion was observed to be minimized when the surface O/N ratio was around 12.

Animals↗
PubMed1997

Further evaluation of the safety and protective efficacy of live attenuated hepatitis A vaccine (H2-strain) in humans.

A study on the possibility of transmission of live hepatitis A vaccine (H2-strain) from vaccinees to nonvaccinees was conducted. As a result, no seroconversion was found among 87 seronegative nonvaccinees, who had a close contact with their 141 subcutaneously vaccinated classmates nor was it found among 101 seronegative children administered the vaccine orally. The above fundings suggest that by losing the ability to be transmitted orally the vaccine virus may result in a decreasing possibility of dissemination among contacts. A 4-year study on the protective efficacy of the H2-strain vaccine was done at 11 primary schools starting at 1991 in Shaoxing County. Since then, there has been no hepatitis A reported among 18102 cumulative person-years in the vaccination group, while 495 cases occurred among 242168 cumulative person-years in the control groups. A large scale vaccination with a cumulative vaccination coverage of 89.45% was carried out in Jiaojiang City among children 1-15 years old. Hepatitis A in this age group in the city, which had 12-87 cases per annum with an average of 32 for 8 years before vaccination, decreased drastically to 0-1 cases after vaccination. The protective efficacy of H2-strain vaccine proved to be satisfactory.

Administration, Oral↗
PubMed1997

Retrobulbar haemodynamic changes studied by colour Doppler imaging in glaucoma.

PURPOSE: To determine the effect of spontaneously elevated intraocular pressure (IOP) on the ocular circulation, and evaluate the result of IOP-lowering procedures in terms of haemodynamics. METHODS: Colour Doppler imaging (CDI) was employed to determine the peak systolic velocity (PSV), end-diastolic velocity (EDV) and time average maximal velocity (TAMV), as well as the Pourcelot ratio (PR) and pulsatility index (PI), of the central retinal artery (CRA), posterior ciliary arteries (PCA) and ophthalmic artery. Various CDI parameters of the eyes with elevated IOP were compared with those of the clinically healthy fellow eyes and the control eyes, separately. Also, data from CDI of glaucoma eyes obtained during the period of elevated IOP and then following IOP-lowering procedures were compared, deliberately avoiding the influence of glaucoma medications. RESULTS: Eyes (n = 12) with elevated IOP showed significantly decreased flow velocities of the CRA and significantly increased PR and PI of the nasal and temporal PCA, compared with the fellow and control eyes, respectively. Following IOP-lowering procedures, the PR and PI of the nasal PCA decreased significantly. CONCLUSION: Spontaneously elevated IOP may induce haemodynamic changes in the CRA and PCA, but no significant change is identified in the ophthalmic artery. Flow velocities tend to decrease while the resistance indices tend to increase with elevated IOP. Such haemodynamic changes may reverse following normalisation of IOP.

Aged↗
PubMed1997

Benign recurrent intrahepatic cholestasis.

Benign recurrent intrahepatic cholestasis is a rare disorder of unknown etiology and has not yet been reported in Taiwan. We report a case with a typical clinical course. A 17-year-old Taiwanese boy had three episodes of pruritus and jaundice from February 1993 to July 1995, each lasting 3 to 4 months. Jaundice spontaneously subsided and he was symptom-free during periods of remission. A fourth episode of pruritus began in July 1995, with jaundice developing later and lasting for 3 months. Laboratory tests revealed direct hyperbilirubinemia. Endoscopic retrograde cholangiopancreatography showed normal intra- and extrahepatic biliary trees. Light microscopy of a liver biopsy sample revealed hepatocellular and canalicular cholestasis with bile retention in the Kupffer cells. Benign recurrent intrahepatic cholestasis was diagnosed after exclusion of other possible causes of jaundice. The patient made an uneventful recovery.

Adolescent↗
PubMed1997

Interspousal transmission of GB virus-C/hepatitis G virus: a comparison with hepatitis C virus.

Although infection with GB virus-C/hepatitis G virus (GBV-C/HGV) by blood transfusion is well documented, little is known about the other routes of transmission. The prevalence of GBV-C/HGV infection in spouses of index patients and the related risk factors were studied. Hepatitis C virus (HCV) and GBV-C/HGV infections were studied in spouses of 100 patients with hepatitis C, of whom 12 were found to be also positive for GBV-C/HGV RNA. For couples both with GBV-C/ HGV viremia, nucleotide sequences of the divergent envelope region were analyzed by phylogenetic tree constructions. For HCV infection, anti-HCV was found in 14 (14%) of the 100 spouses. Five spouses (42%) of the 12 patients with dual infection of GBV-C/HGV and HCV had evidence of GBV-C/HGV infection, three had viral RNA, and two had antibodies to a recombinant HGV envelope protein E2. Nucleotide sequence comparison and phylogenetic tree analysis of the genome in the GBV-C/HGV infected couple revealed the isolates to be closely related. These results suggest that spouses of patients with GBV-C/HGV infection are at a higher risk of acquiring GBV-C/HGV as compared with HCV, and they should be educated to avoid GBV-C/HGV infection from their spouses, in case GBV-C/HGV is shown to be pathogenic.

Adenovirus E2 Proteins↗
PubMed1997

Combined trabeculectomy and extracapsular cataract extraction with mitomycin C.

BACKGROUND: To evaluate the long-term intraocular pressure (IOP) reduction effect and safety of adjunctive mitomycin C (MMC) (0.02%) in combined trabeculectomy and extracapsular cataract extraction (ECCE) procedure. METHODS: Thirty of forty-one consecutive patients who underwent MMC trabeculectomy and ECCE with a minimum follow-up of 12 months were evaluated. RESULTS: The mean IOP was reduced significantly (p < 0.001) from preoperative 19.2 +/- 3.2 mmHg to postoperative 12.1 +/- 2.7 mmHg, while the mean number of medications decreased from 2.1 to 0.2 at 1-year follow-up. Twenty-seven (90%) patients had IOPs controlled at 15 mmHg or less, and 26 (86.7%) patients required no medication. Net astigmatism and polar value converted from keratometric readings were 1.43 +/- 0.94 diopters and 0.07 +/- 1.38 diopters, respectively, in 1-year follow-up, which were not significantly different from the preoperative values. CONCLUSIONS: Intraocular pressure could be maintained in the low teens without the need for medication in a majority of patients even one year after the combined procedure. No adverse effect on corneal endothelium or limbal wound healing was detected with intraoperative application of 0.02% MMC.

Aged↗
PubMed1996

ET-Kyoto solution for 48-hour canine lung preservation.

BACKGROUND: ET-Kyoto (ET-K) solution, proven safe for 20-hour lung preservation, was modified to achieve longer preservation: ET-K2 solution with more buffer capacity and ET-K3 with less potassium. METHODS: Lungs were preserved with one of the three solutions (with prostaglandin E1 at 4 degrees C for 48 hours (n = 5 for each). Left lung transplantation was performed and evaluated for 6 hours. RESULTS: Each solution became acidic after preservation (p < 0.01), though the change was lowest in the ET-K2 solution. All animals in the ET-K and ET-K3 groups survived for 6 hours after reperfusion, but only 1 survived in the ET-K2 group (p < 0.05). In all groups, partial pressure of oxygen in arterial blood decreased gradually after reperfusion. Pulmonary vascular resistance after reperfusion was significantly lower in the ET-K group than in the ET-K3 group (p < 0.01). Scanning electron microscopic examination showed that endothelial cell swelling and disruption were milder in the ET-K group (with the solution containing potassium of 44 mEq/L) than in the ET-K3 group. CONCLUSION: Lung preservation can be achieved for 48 hours in ET-K and ET-K3 solutions. Enhancement of buffer capacity provides no advantage. Potassium at 44 mEq/L does not cause deterioration of endothelial cells.

Animals↗
PubMed1996

Effective 30-hour preservation of canine lungs with modified ET-Kyoto solution.

BACKGROUND: With the aim of developing a preservation solution that can preserve donor lungs reliably for a long time, we prepared a modified ET-Kyoto solution by adding N-acetylcysteine, nitroglycerin, and dibutyryl adenosine 3', 5'-cyclic phosphate to the previously reported ET-Kyoto solution, which contains trehalose, gluconate, and hydroxyethyl starch. In this study, we examined the efficacy of modified ET-Kyoto solution in 30-hour lung preservation. METHODS: Twenty five pairs of adult mongrel dogs were divided into four groups. Donor lungs were flushed with modified ET-Kyoto solution (n = 9), with ET-Kyoto solution (n = 6), with University of Wisconsin solution group (n = 6), or with ET-Kyoto solution plus the solvents of nitroglycerin (ethanol and propylene glycol) (n = 4), then stored at 4 degrees C for 30 hours. All animals were treated with prostaglandin E1. Left lungs were transplanted and reperfused for 6 hours. RESULTS: With respect to arterial oxygen tension, peak inspiratory pressure, and wet-to-dry lung weight ratio, modified ET-Kyoto solution was significantly superior to ET-Kyoto solution. The modified ET-Kyoto solution was significantly superior to University of Wisconsin solution with respect to survival rate, arterial oxygen tension, and wet-to-dry lung weight ratio. Ultrastructural findings supported these results. CONCLUSIONS: These results suggest that modified ET-Kyoto solution is superior to University of Wisconsin solution for 30-hour lung preservation.

Acetylcysteine↗