Biomedical subjects

C J Huang

Publications and source records attributed to C J Huang.

At least 91 records · Page 5Linked to original sources

PubMed1996

Genomic structure of carp mitogen-activated protein kinase kinase 1 gene.

Carp mitogen-activated protein kinase kinase 1 (cMKK1) gene was isolated from a liver genomic library. The sequence around the exon-intron boundaries and 2 kb of the promoter region were determined. Our data indicate that this gene is composed of 11 exons and 10 introns spanning about 9 kb. Multiple potential transcription initiation sites were located by primer extension analysis. Examination of 2 kb of 5'-flanking sequence revealed potential binding sites for a variety of transcription factors such as E2F, Ets-1, GATA-1, Myb, NF-IL6, Sp1, and NF-kB.

Amino Acid Sequence↗

PubMed1996

Clinicopathologic study of advanced gastric cancer without serosal invasion in young and old patients.

Fifty-seven patients treated by radical gastric resections were retrospectively studied to understand the clinicopathologic characteristics of advanced gastric cancer without serosal invasion (the depth of tumor invasion limited to the muscularis propria or subserosal layer) in young and old age persons. There were 36 patients in the old age group (age > 60 years) and 21 in the young age group (age < or = 40 years). The clinical and pathologic parameters for this study included sex, gross type, location, maximum tumor size, depth of invasion, lymph node metastasis, tumor stage, histologic type, and rate of curative resection. The old patients had a higher percentage of small tumors, subserosal invasion and lymph node metastasis, but these parameters were not significantly different from those of the young patients, nor did the sex ratio, gross type, location, and rate of curative resection show significant differences. The histologic feature was the only statistically significant parameter, determined by univariate and multivariate analyses. Poorly differentiated adenocarcinoma and signet ring cell carcinoma were detected in 10 (47.6%) and 4 (19.0%) of the 21 younger patients, respectively, while there were 4 (11.1%) and 2 (5.6%) in the old age group. Although the gastric cancer in young patients had more aggressive histologic characteristics than it did in elderly patients, survival rates between the two groups did not differ to any great degree. Our findings indicate that the prognosis for younger patients with advanced gastric cancer without serosal invasion was favorable when curative resection was performed.

Adenocarcinoma↗

PubMed1996

Characterization of Perina nuda nucleopolyhedrovirus (PenuNPV) polyhedrin gene.

The Perina nuda nucleopolyhedrovirus (PenuNPV) polyhedrin gene was located in EcoRI-G (6.3 kilobase pairs; kbp) and PstI-G (4.3 kbp) fragments of its genomic DNA. A portion of 1333 nucleotides (nt) containing this gene was sequenced. An open reading frame of 735 nt encoded a 245-amino-acid-long polyhedrin. A conserved TAAG motif which is associated with transcriptional start sites was identified 51 nt upstream of the translation initiation codon of PenuNPV polyhedrin gene. A putative polyadenylation signal, AATAAA, was found 116 nt downstream of the termination codon (TAA). Comparison of the amino acid sequences of PenuNPV polyhedrin with those of other NPVs showed that PenuNPV polyhedrin was most closely related to Orgyia pseudotsugata multiple NPV (OpMNPV) polyhedrin.

Amino Acid Sequence↗

PubMed1996

Purification and molecular cloning of carp ovarian cystatin.

The ovarian fluid of carp consists of many components. Using the antiserum against carp serum, Western blot analysis of ovarian fluid was done in order to distinguish substances synthesized by the ovary from those derived from the serum. Several ovary-specific substances were detected including a protein of 12 kDa (p12), which was purified to homogeneity. Purified p12 displays a single band in SDS-PAGE under nonreducing condition and it can inhibit the enzymatic activity of papain with an apparent inhibition constant of 0.01 nM. The primary structure of p12 was partially determined by Edman degradation and fully elucidated by molecular cloning. A cDNA of 531 bp encoding p12 was obtained. The precursor of p12 has 129 residues, including a signal peptide of 18 residues and a mature protein of 111 residues. The N- and C-terminus of p12 are threonine and methionine, respectively. The p12 shares many common features of the family 2 cystatins of other species, including the similarity of the protein size (in the range of 110 to 120 residues), the presence of 4 cysteine residues and the occurrence of invariant residues throughout the molecule.

Amino Acid Sequence↗

PubMed1996

Expression, characterization, and genomic structure of carp JAK1 kinase gene.

A 3.7-kb cDNA encodes the carp JAK1 kinase of 1,156 amino acid residues. The overall amino acid sequence identity between carp JAK1 and murine JAK1, JAK2, JAK3, and human TYK2 is 57%, 35.5%, 31.3%, and 42.4%, respectively. In addition, carp JAK1 shows higher sequence homology to mammalian JAK1 in both the kinase-like (JH2) and kinase (JH1) domains (approximately 70% identity). Therefore, carp JAK1 is a homolog of mammalian JAK1. To investigate the possible function of JH2 domain, full-length, and various truncated forms of carp JAK1 were produced in the baculovirus system. Our results demonstrate that c-JH1 and c-JH2 associate with each other and c-JH2 can be tyrosine-phosphorylated by c-JAK1 and by c-JH(1 + 2). The JAK1 gene was also isolated from a carp genomic library and characterized. This gene is divided into 24 exons spanning at least 31 kb of genomic DNA. Exon 1 contains the 5'-untranslated region and exon 2 contains the putative translation initiation site. The 2.5-kb DNA region upstream of the transcription initiation site contains numerous potential binding sites for transcription factors including NF-IL6, HNF-5, AP1, GHF-5, and E2A. When this DNA fragment was placed upstream of the chloramphenicol acetyltransferase (CAT) reporter gene and transfected into a carp CF cell line, it could drive the synthesis of CAT enzyme 16 times more efficiently than the promoterless pCAT-Basic. Deletion analysis defined a positive regulatory region between -1,023 and -528. A smaller region (-181 to +59) without any typical TATA-box sequences, G + C-rich sequences, or other binding sequences for known transcription factors still had promoter activity. Constructs without this region did not have detectable promoter activity. This suggests that this region of DNA may play an important role in the expression of carp JAK1 gene.

Amino Acid Sequence↗

PubMed1996

Dietary oxidized frying oil enhances tissue alpha-tocopherol depletion and radioisotope tracer excretion in vitamin E-deficient rats.

Rats fed a diet containing 15% oxidized frying soybean oil (OFO) have been shown to have significantly lower tissue alpha-tocopherol (alpha-T) concentration than rats fed a 15% fresh soybean oil diet. To examine the turnover of alpha-tocopherol, a depletion-repletion experiment and a radioisotope tracer study were conducted. Two groups of male weanling Long-Evans rats were fed vitamin E-deficient diets containing either 15% OFO or 15% vitamin E-stripped fresh soybean oil (control). After 9 wk of depletion, rats fed the OFO diet had significantly higher plasma pyruvate kinase (PK) activity and lower concentrations of alpha-T in RBC, adrenal gland, heart, kidney, liver, spleen, testis and muscle compared with controls (P < 0.05), indicating that the vitamin E-deficient status was aggravated by feeding the OFO diet. After 12 wk, the depleted rats were intraperitoneally injected with a dose of all-rac-alpha-T (2.5 mg/rat, dissolved in Vitamin E-stripped corn oil) every other day. Three doses were administered to each rat during the 1-wk repletion period. Plasma PK activity decreased in both groups (P < 0.05) after repletion but that of the OFO rats was still significantly higher than that of the control group. The repleted OFO gorup also had significantly lower alpha-T concentration in adrenal gland, epididymal fat, liver and spleen than the repleted control group. Two rats from each group that had been vitamin E-depleted for 16 wk were injected intraperitoneally with a single dose of 5-methyl-14C-RRR-alpha-T (740 kBq/kg body weight). During the week after dosing, the radioactivity excreted in urine and feces of the OFO group was 1.3- and 1.7-fold, respectively, that of the control group. Tissue retention of radioactivity was also lower in the OFO rats than in the control rats. The results suggest that more of the alpha-T in the body was catabolized or turned over in rats fed the OFO-containing diet.

Adrenal Glands↗

PubMed1996

Pyogenic hepatic abscess. Changing trends over 42 years.

OBJECTIVE: The authors document changes in the etiology, diagnosis, bacteriology, treatment, and outcome of patients with pyogenic hepatic abscesses over the past 4 decades. SUMMARY BACKGROUND DATA: Pyogenic hepatic abscess is a highly lethal problem. Over the past 2 decades, new roentgenographic methods, such as ultrasound, computed tomographic scanning, direct cholangiography, guided aspiration, and percutaneous drainage, have altered both the diagnosis and treatment of these patients. A more aggressive approach to the management of hepatobiliary and pancreatic neoplasms also has resulted in an increased incidence of this problem METHODS: The records of 233 patients with pyogenic liver abscesses managed over a 42-year period were reviewed. Patients treated from 1952 to 1972 (n = 80) were compared with those seen from 1973 to 1993 (n = 153). RESULTS: From 1973 to 1993, the incidence increased from 13 to 20 per 100,000 hospital admissions (p < 0.01. Patients managed from 1973 to 1993 were more likely (p < 0.01) to have an underlying malignancy (52% vs. 28%) with most of these (81%) being a hepatobiliary or pancreatic cancer. The 1973 to 1993 patients were more likely (p < 0.05) to be infected with streptococcal (53% vs. 30%) or Pseudomonas (30% vs. 9%) species or to have mixed bacterial and fungal 26% vs. 1%) infections. The recent patients also were more likely (p < 0.05) to be managed by percutaneous abscess drainage (45% vs. 0%). Despite having more underlying problems, overall mortality decreased significantly (p < 0.01) from 65% (in 1952 to 1972 period) to 31% (in 1973 to 1993 period). The reduction was greatest for patients with multiple abscesses (88% vs. 44%; p < 0.05) with either a malignant or a benign biliary etiology (90% vs. 38%; p < 0.05). Mortality was increased (p < 0.02) in patients with mixed bacterial and fungal abscesses (50%). From 1973 to 1993, mortality was lower (p = 0.19) with open surgical as opposed to percutaneous abscess drainage (14% vs. 26%). CONCLUSIONS: Significant changes have occurred in the etiology, diagnosis, bacteriology, treatment, and outcome patients with pyogenic hepatic abscesses over the past 4 decades. However, mortality remains high, and proper management continues to be a challenge. Appropriate systemic antibiotics and fungal agents as well as adequate surgical, percutaneous, or biliary drainage are required for the best results.

Age Distribution↗

PubMed1996

The herpes simplex virus type 1 VP5 promoter contains a cis-acting element near the cap site which interacts with a cellular protein.

The promoter controlling the expression of the transcript encoding the major herpes simplex virus type 1 capsid protein (VP5, UL19) extends only 60 bases or so from a functional Sp1 site at --48 to include a cis-acting element 3' of the transcript start site. In the present communication, we report the generation of recombinant viruses bearing mutations between --6 and + 8 relative to the cap site in the VP5 promoter controlling expression of a reporter gene. Analysis of the effects of these mutations upon reporter gene expression along with the results of protein binding assays demonstrates that this cap transcription element functionally interacts with a cellular protein of a normal size of 40 kDa. Thus, like the strict late UL38 promoter characterized earlier, the late VP5 promoter has the essential properties of a cellular promoter.

Animals↗

PubMed1996

Red cell vitamin E and oxidative damage: a dual role of reducing agents.

The purpose of this study was to determine the role of reducing agents in maintaining the integrity of vitamin E-deficient red cells. Three groups of one-month-old male Wistar rats were fed a basal vitamin E-deficient diet supplemented with either 0, 10 or 100 mg d, 1-alpha-tocopheryl acetate per kg diet for up to 12 weeks. Washed red blood cells (5%) were resuspended in saline-phosphate buffer, pH 7.4, and were incubated at 37 degrees C with or without containing 12.5 mM 2, 2'-azobis (2amino- propane) dihydrochloride (AAPH), 2.8 mM glucose, 1 mM ascorbic acid, 10 mM hydrogen peroxide (H2O2), 250 microM dimethylsulfoxide (DMSO) or 2.8 mM deoxyribose (DR) for up to 20 hours. Addition of either glucose, AAPH, ascorbic acid or H2O2 markedly accelerated the rates of hemolysis and lipid peroxidation in the red cells of vitamin E-deficient rats. On the contrary, both glucose and ascorbic acid were protective against oxidative damage to the red cells of vitamin E-supplemented rats in a dose-dependent manner. Also, vitamin E-supplemented red cells were more resistant to AAPH and H2O2 than the deficient cells. DMSO or. DR had no significant effects on the rates of hemolysis or lipid peroxidation. Glucose, but not others, maintained or slowed down the loss of glutathione (GSH) during incubation. The results obtained suggest a dual role of ascorbic acid and GSH in the function of vitamin E in maintaining red cell integrity: these reducing agents may exert antioxidant function by participating in vitamin E regeneration when certain levels of vitamin E is maintained, but promote oxidative damage by enhancing free radical generation when vitamin E is low or depleted.

Amidines↗

PubMed1996

Patterns of distant metastases in nasopharyngeal carcinoma.

The distant metastasis in nasopharyngeal carcinoma has remained the major cause of mortality and treatment failure despite better locoregional control of the disease in the past decades. Between 1987 and 1992, 125 out of 629 cases of nasopharyngeal carcinoma were found to have distant metastasis. The location of metastatic site, the timing and median survival were analyzed. The diagnosis of distant metastasis in the retrospective study was based on radiography, computed tomography, skeletal scintigraphy, abdominal sonography and pathology reports. The results showed that the frequencies of metastases were as follows: bone (75% of total metastatic patients), lung (46%), liver (38%), retroperitoneal lymph nodes (10%). Multiple organ involvement was high (57%). Most of the distant metastases (95%) occurred within 3 years after completion of radiotherapy, the first year (52%), the second year (23%) and the third year (20%). The median survival time from the discovery of distant metastasis was 11.2 months for bone metastasis, 16.3 months for pulmonary metastasis, and 3.2 months for hepatic metastasis. The results revealed that the skeletal system was the most common site of distant metastasis, followed by lung and liver. The incidence of retroperitoneal lymphadenopathy is higher than previous reports.

Adult↗

PubMed1996

Expression of P53 protein and it's prognostic significance in breast cancer patients.

Nuclear accumulation of p53 protein is associated with a poor clinical outcome in breast cancer patients. This study was designed to determine the frequency of p53 protein immunoreactivity in primary breast cancer to correlate the presence of p53 protein with established risk factors including the estrogen receptor and progesterone receptor status, and to evaluate the prognostic significance of p53 protein immunoreactivity regarding patient survival in Taiwan. To assess the p53 protein immunoreactivity, 104 patients with breast cancer were examined using immunohistochemical methods. P53 protein was detected in 40 (38.5%) of these primary breast cancer specimens. Highly significant associations were found between p53 protein expression and negative steroid receptors, histologic grade III. There were no statistically significant references in p53 protein expression with respect to age, tumor size, lymph node status, or clinical stage. Patients with p53 positive tumor showed poorer survival but this did not achieve significance. However, there were more patients with poor survival in the axillary node-positive group (p < 0.05) than in node-negative group. This suggests that the p53 protein expression is marginal as a prognostic indicator in breast cancer with axillary-node metastasis.

Adult↗

PubMed1995

Jun-B oncogene aberrations in cervical cancer cell lines.

We describe here structural and expression analysis of the jun-B oncogene in two cervical cancer cell lines. In the CC7T-a cell line, results from both Southern analysis and cDNA cloning studies revealed the existence of two structurally altered jun-B alleles besides the normal gene. One of the altered alleles was due to a type 16 human papillomavirus (HPV-16) integration event, whereas the other allele was a consequence of a chromosomal translocation involving chromosome 19 (jun-B) and an EST182 locus residing in chromosome 15. In the HeLa cell line, which contains integrated HPV-18, an apparent structural aberration, a 3-fold amplification and a 3-fold overexpression of the jun-B gene were observed. Our observations suggest that deregulation of the jun-B gene expression may have contributed to the transformation process in these two cervical cancer cell lines.

Alleles↗

PubMed1995

A protease inhibitor of the serpin family is a major protein in carp perimeningeal fluid: I. Protein purification and characterization.

Two isoforms of a protease inhibitor of the serpin family (p62) have been purified from bighead carp perimeningeal fluid. Both isoforms migrate with an apparent molecular mass of 62 kDa on reducing and nonreducing sodium dodecyl sulfate-polyacrylamide gels. Both proteins inhibited the activities of bovine trypsin, bovine chymotrypsin, and porcine pancreatic elastase. They also formed complexes with these proteases that were resistant to sodium dodecyl sulfate treatment. p62 exists in the extracts of all tissues examined, including brain, head kidney, kidney, liver, muscle, ovary, pituitary, and spleen. It is also present in serum, ovarian fluid, and milt as well as perimeningeal fluid. The protease inhibitor is a glycoprotein, and its carbohydrate moiety could be removed by endoglycosidase F. Because p62 resembles mammalian alpha 1-antitrypsin in many aspects, it is likely a fish equivalent of alpha 1-antitrypsin.

Animals↗

PubMed1995

A protease inhibitor of the serpin family is a major protein in carp perimeningeal fluid: II. cDNA cloning, sequence analysis, and Escherichia coli expression.

A cDNA clone, pCP9, has been isolated from a common carp liver cDNA library by immunoscreening with polyclonal antiserum raised against purified bighead carp alpha 1-antitrypsin. This clone is 1,396 bp in length and has an open reading frame encoding a protein of 410 amino acid residues. The deduced amino acid sequence shows moderate homology to human alpha 1-antitrypsin (38%), guinea pig contrapsin (35%), human alpha 1-antichymotrypsin (34%), and human proteinase C inhibitor (31%), all members of the serine protease inhibitor (serpin) family. To confirm further that the cDNA clone was derived from the authentic carp alpha 1-antitrypsin gene, the presumptive mature protein of pCP9 was expressed in Escherichia coli. The molecular mass of the recombinant protein matched that predicted from the nucleotide sequence. This recombinant protein, which was recognized by antiserum against native alpha 1-antitrypsin, was capable of formation of serpin-enzyme complexes with trypsin, chymotrypsin, and elastase. Therefore, we conclude that the protein encoded by the pCP9 clone is indeed carp alpha 1-antitrypsin. Expression of alpha 1-antitrypsin in brain was confirmed by reverse transcription and polymerase chain reaction performed on mRNA derived from both common carp and bighead carp brain.

Amino Acid Sequence↗

PubMed1995

Tissue alpha-tocopherol retention in male rats is compromised by feeding diets containing oxidized frying oil.

To investigate the effect of dietary oxidized frying oil (OFO) on tissue retention of alpha-tocopherol (alpha-T). Long-Evans male weanling rats were divided to four groups based on a 2 x 2 factorial design. Two groups were fed 15% OFO diets, and the remaining two groups were fed control diets in which OFO was replaced by vitamin-E-stripped fresh soybean oil. Vitamin E as all-rac-alpha-tocopheryl acetate was added at the concentration of either 50 (normal E) or 500 (high E) mg/kg diet. The OFO sample was prepared by deepfrying sticks in fresh soybean oil at 205 +/- 5 degrees C for four 6-h periods. After 6 wks of feeding, alpha-T concentrations in most tissues were significantly lower in rats fed OFO diets (P < 0.05) than in the control groups. For rats fed the OFO diet with the normal vitamin E concentration, the alpha-T concentration is epididymal fat pad, plasma, liver, kidney, muscle, brain and lung were 29-64% those of the corresponding control group (P < 0.05). The interaction between the two dietary factors on tissue alpha-T was significant in liver, spleen, and adrenal gland. In these three tissues, the differences between the normal and high dietary vitamin E groups were less in rats fed the OFO diets than in rats fed the control diets. The tissue alpha-T concentrations of the high vitamin E OFO group were comparable with or higher (P < 0.05) than those of the normal vitamin E control group, indicating that the negative effect of OFO on tissue alpha-T concentration can be alleviated by dietary supplementation of vitamin E. Compared with the controls, rats OFO diets had significantly higher tissue thiobarbituric acid reactive substances (P < 0.05). Because the amount of alpha-T directly added into the test oil samples was not significantly decreased through an incubation (at 37 degrees C) period of up to 10 d, the inefficient absorption and/or enhanced catabolism or turnover of vitamin E may be involved in the inferior tissue alpha-T retention of OFO fed rats.

Adrenal Glands↗

PubMed1995

Overlapping initiator and TATA box functions in the basal core promoter of hepatitis B virus.

The regulation of transcription of the hepatitis B virus core promoter is an important event in the viral life cycle. Two messages, precore and pregenomic RNAs, that are initiated 30 nucleotides apart are produced by the core promoter. Precore RNA encodes nucleocapsid protein and pregenomic RNA core and polymerase. The latter transcript also serves as a template for viral genome replication via reverse transcription. We have previously defined a basal core promoter, which contains four TA-rich sequences (TA1 through TA4) but no canonical TATA element, that can direct transcription of both messages. In this study, we demonstrated that a stretch of 15 nucleotides containing TA4 is sufficient to direct precise initiation of both precore and pregenomic transcripts. This sequence can function as both an initiator and a TATA element. Mutational analysis further revealed that sequences essential for either function are colocalized. The significance of this finding with respect to the basal transcription mechanism and regulation of viral gene expression is discussed.

Base Sequence↗

PubMed1995

Frozen section of diagnosis of breast lesions.

Frozen section diagnosis rendered in 549 consecutive breast biopsies performed in 5 years in a single pathology laboratory was correlated with the final pathological diagnosis. There were no false positive reports among the 220 (40.1%) biopsies interpreted as benign lesions in paraffin sections. Among 329 (59.9%) malignant biopsies on paraffin sections, 3 cases were interpreted as benign lesions on frozen sections. Three false negatives included 2 ductal carcinoma in situ and one infiltrating ductal carcinoma associated with papillomatosis. The tumors were small and confined to the breast without any evidence of metastasis. There was a very good correspondence between the frozen section diagnosis and the paraffin section diagnosis (K = 0.98). The sensitivity of frozen section diagnosis was 99.1% and the clinical diagnostic specificity was 100%. Our results suggest that frozen section diagnosis is a highly reliable procedure, but small lesions (less than 1 cm in diameter, or non-palpable) should not be subjected to frozen section examination to avoid unnecessary loss of neoplastic tissue during the frozen section. The careful investigation of paraffin-embedded tissue is recommended for small breast lesions in breast conserving lumpectomy.

Breast Diseases↗

PubMed1995

[Effects of pentagastrin with intracerebroventricular injection on blood pressure and heart rate in rats].

Experiments were carried out on 84 artifially ventilated SD rats anaesthetized with urethane and immobilized with gallamine triethiodide. Injection of pentagastrin (G5) into the rat lateral ventricle resulted in a marked elevation in arterial blood pressure which reached its peak at 3 min (from 12.2 +/- 1.5 to 14.1 +/- 1.7 kPa) and also a significant increase in heart rate from 435 +/- 53.9 to 471.6 +/- 53.2 beats/min. This effect of G5 could be partially antagonized by injection of phentolamine (alpha-receptor antagonist, 10 micrograms) into the lateral ventricle, but not by propanolol (beta-receptor antagonist, 4 micrograms) or atropine (M-receptor antagonist, 4 micrograms). These findings indicate that the central effect of G5 on blood pressure and heart rate is partly mediated by alpha-receptor.

Animals↗