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H J Harn

Publications and source records attributed to H J Harn.

At least 37 records · Page 2Linked to original sources
PubMed1997

Apoptosis occurs more frequently in intraductal carcinoma than in infiltrating duct carcinoma of human breast cancer and correlates with altered p53 expression: detected by terminal-deoxynucleotidyl-transferase-mediated dUTP-FITC nick end labelling (TUNEL).

AIMS: We examined the relationship between apoptosis and three different major stages of human breast carcinoma: intraductal carcinoma (DCIS), infiltrating duct carcinoma (IDC) and metastatic carcinoma in lymph nodes. We also determined the correlation between apoptosis and oestrogen receptor (ER), progesterone receptor (PR) and p53. METHODS AND RESULTS: The study investigates the extent of apoptosis in 63 breast carcinomas by in-situ end-labelling, in formalin-fixed, paraffin-processed tissue sections. The 63 breast carcinomas, included 22 DCISs, 26 IDCs, three infiltrating lobular carcinomas (ILC) and 12 metastatic lymph nodes. The apoptotic labelling index was higher in DCIS than IDC and metastatic carcinoma (P < 0.001, P < 0.007, respectively). By immunohistochemistry, we also analysed p53, ER and PR. Apoptosis correlated significantly with p53 (r = 0.748, P = 0.0004) in IDC. Also, ER correlated significantly with PR (r = 0.629, P = 0.00001). No apparent correlation was found between the apoptosis and ER or PR. CONCLUSION: Our data suggest that not only does apoptosis differ between intraductal carcinoma and infiltrating carcinoma but also it might be regulated by altered p53 expression.

Apoptosis↗
PubMed1997

Angiotensin I converting enzyme gene polymorphism and insulin resistance in patients with hypertension.

BACKGROUND: The homozygote deletion (DD) genotype of the angiotensin I converting enzyme (ACE) gene has been shown to be associated with an increased risk of coronary heart disease independent of other risk factors. OBJECTIVE: To investigate the possible association of the insertion/deletion (I/D) polymorphism of the ACE gene with insulin resistance in a Chinese population with and without hypertension. SUBJECTS AND METHODS: The I/D polymorphism of the ACE gene was determined for 361 Chinese including 148 women and 96 men with normal blood pressures and 64 male and 53 female patients with mild-to-moderate hypertension. Insulin resistance was estimated by the insulin suppression test and glucose intolerance evaluated with an oral glucose-tolerance test for all of the subjects. RESULTS: Three hypertensive subgroups with DD, DI and II genotypes having similar ages and body mass indexes presented insignificantly different degrees of glucose intolerance and insulin resistance both among men and among women. Similar results were found for normotensive subjects. In addition, ACE genotypes were not significant predictors of insulin resistance and glucose intolerance either among men or among women after adjustment for age, body mass index, and hypertension. CONCLUSION: The present data indicated that the I/D polymorphism of the ACE gene was not related to insulin resistance for Chinese hypertensive and normotensive subjects. The increased risk of coronary heart disease associated with the DD genotype need not be mediated through the mechanism of insulin resistance and glucose intolerance for Chinese patients with hypertension.

Adult↗
PubMed1997

Evidence of transmission of Mycobacterium tuberculosis by random amplified polymorphic DNA (RAPD) fingerprinting in Taipei City, Taiwan.

AIMS: To determine, by strain identification of Mycobacterium tuberculosis, whether transmission has occurred between individuals or whether new strains are present. METHODS: A rapid protocol for random amplified polymorphic DNA (RAPD) analysis was developed. This protocol was applied to 64 strains of M tuberculosis that had been confirmed by culture and microbiological methods. RESULTS: There are five groups of M tuberculosis prevalent in Taipei city, Taiwan. The major types are groups I and III. Groups I and II had been prevalent until the end of last year when, according to our group analysis, they had been eradicated. However, group III was continuously present from the middle of 1995 to the middle of 1996, and group IV was present at the end of both years, which indicated that both groups were transmitted continuously. These clustered strains had demographic characteristics consistent with a finding of transmission tuberculosis. Also, there were 13 of 64 strains with unique RAPD fingerprints that were inferred to be due primarily to the reactivation of infection. In the drug resistance analysis, the major type represented included group III and part of group IV. CONCLUSIONS: Our preliminary data imply, not only that the prevalence of M tuberculosis in Taipei city is due to transmission rather than reactivation, but that drug resistance also may play a role in tuberculosis transmission.

Bacterial Typing Techniques↗
PubMed1997

PGE1, dexamethasone, U-74389G, or Bt2-cAMP as an additive to promote protection by UW solution in I/R injury.

A method to reduce ischemia-reperfusion (I/R) injury can be an important criterion to improve the preservation solution. Although University of Wisconsin solution (UW) works as a lung preservation solution, its attenuation effect on I/R injury has not been investigated. We attempted to determine whether, by adding various protective agents, modified UW solutions will enhance the I/R attenuation by UW. We examined the I/R injury in an isolated rat lung model. Various solutions, e.g., physiological salt solution (PSS), UW, and modified UW solutions containing various protective agents such as prostaglandin E1, dexamethasone, U-74389G, or dibutyryl adenosine 3',5'-cyclic monophosphate were perfused individually to evaluate the I/R injury. Isolated rat lung experiments, with ischemia for 45 min, then reperfusion for 60 min, were conducted in a closed circulating system. Hemodynamic changes, lung weight gain (LWG), capillary filtration coefficient (Kfc), protein content of lavage fluid, concentration of cytokines, and lung histopathology were analyzed. Results showed that the acute I/R lung injury with immediate permeability pulmonary edema was associated with an increase in tumor necrosis factor-alpha (TNF-alpha) production. A significant correlation existed between TNF-alpha and Kfc (r = 0.8, P < 0.0001) and TNF-alpha and LWG (r = 0. 9, P < 0.0001), indicating that TNF-alpha is an important cytokine modulating early I/R injury. Significantly lower levels of Kfc, LWG, TNF-alpha, and protein concentration of lung lavage (P < 0.05) were found in the UW-perfused group than in the control group perfused with PSS. Modified UW promoted the protective effect of UW to further decrease Kfc, LWG, and TNF-alpha (P < 0.05). Histopathological observations also substantiated this evidence. In the UW+U-74389G group, bronchial alveolar lavage fluid contained lowest protein concentration. We conclude that the UW solution attenuates I/R injury of rat lung and that the modified UW solutions further enhance the effect of UW in reducing I/R injury. Among modified solutions, UW+U-74389G is the best. Further investigation of the improved effects of the modified UW solutions would be beneficial in lung transplantation.

Adenosine↗
PubMed1996

Expression of Epstein-Barr virus-encoded RNAs as a marker for metastatic undifferentiated nasopharyngeal carcinoma.

BACKGROUND: Epstein-Barr virus (EBV) is associated with undifferentiated nasopharyngeal carcinoma (NPC). EBV-encoded nonpolyadenlyated RNAs (EBERs) are often used as a marker to detect EBV-infected NPC cells. This study was conducted to document the expression and determine the significance of EBERs in NPC cells at various metastatic sites. METHODS: An in situ hybridization (ISH) technique was used to identify the presence of EBERs in paraffin embedded tissues of primary and metastatic sites obtained from 21 patients with NPC. Nineteen of these patients had undifferentiated lesions, and 2 had squamous cell carcinoma. One hundred and fifty specimens of normal tissues and tissues from patients with a variety of benign and malignant diseases other than NPC served as controls. In the NPC specimens, the expression of latent membrane protein (LMP) and a lytic protein, BZLF-1, were also examined by immunohistochemistry. RESULTS: Tissues from all patients with undifferentiated NPC and one patient with squamous cell carcinoma contained EBERs in the malignant cells; the other case of squamous cell carcinoma was negative. In metastatic NPCs, LMP was expressed in 18% (4 of 22) of tissues whereas BZLF-1 was not expressed in any tissues. EBERs were not detected in the 43 patients with normal tissues and benign lesions. In malignant diseases other than NPC, EBERs were detected in only 2 of 12 cases of non-Hodgkin's lymphoma, 1 of 2 cases of Hodgkin's lymphoma, and 1 of 6 cases of gastric cancer. CONCLUSIONS: By virtue of the direct correlation between latent EBV infection and NPC, the authors conclude that EBERs can be used as a sensitive marker to identify NPC cells at various metastatic sites by techniques of in situ hybridization, and that demonstration of EBERs in lesions of undifferentiated histology may be useful as a diagnostic adjunct for NPC presenting as metastatic cancer of unknown origin.

Biomarkers, Tumor↗
PubMed1996

Postextubation laryngeal edema in adults. Risk factor evaluation and prevention by hydrocortisone.

OBJECTIVE: To evaluate the risk factors for postextubation laryngeal stridor and its prevention by hydrocortisone in adult patients. DESIGN: Prospective, randomized, double-blind, placebo controlled study. SETTING: Medical and surgical ICU of a tertiary teaching hospital. PATIENTS: 77 consecutive patients of both sexes, who had undergone tracheal intubation for more than 24 h and fulfilled the weaning criteria, were eligible for the study. Patients were excluded if they were less than 15 years of age, had a disease or the surgery of the throat, or had been extubated during the current hospitalization. INTERVENTION: The control group received placebo (normal saline 3 cc) and the experimental group received hydrocortisone 100 mg by intravenous infusion 60 min before extubation. MAIN OUTCOME MEASURES: Patients were observed 24 h after extubation for symptoms or signs of laryngeal edema or stridor: prolonged inspiration with accessory usage of respiratory muscles or crowing sound with inspiration or reintubation. RESULTS: The overall incidence of postextubation stridor was 22% (17/77). Only one patient (1%), who belonged to the control group, needed reintubation. 39% of female patients and 17% of male patients developed stridor. The relative risk of females developing this complication was 2.29. 7/39 of the hydrocortisone group and 10/38 of patients in the control group developed postextubation stridor. CONCLUSIONS: Hydrocortisone did not significantly reduce the incidence of postextubation laryngeal edema or stridor. From the risk factors evaluated, we were unable to demonstrate a statistical correlation between postextubation stidor and the duration of the intubation, the patient's age, the internal diameter of the endotracheal tube, or the route of intubation. However, female patients were more likely to develop this complication.

Aged↗
PubMed1996

Down regulation of bcl-2 by p53 in nasopharyngeal carcinoma and lack of detection of its specific t(14;18) chromosomal translocation in fixed tissues.

High levels of bcl-2 protein have been found in a wide variety of human cancers. Since p53 gene inactivation occurs in over half of human cancers, it is possible that loss of p53-mediated repression of bcl-2 gene expression accounts, at least in part, for the frequent abnormalities in bcl-2 protein production seen in tumours. By using immunohistochemical methods, we have analysed thirty-three nasopharyngeal carcinomas for p53 and bcl-2 expression. We found an inverse correlation between the expression of these two proteins (P < 0.001). Moreover, we utilized universal oligonucleotide primers of a region 5' to the bcl-2 MBR and at the 3' end of JH segments to initiate a DNA polymerase chain reaction that amplified these bcl-2-JH junctures. Of the twelve nasopharyngeal carcinomas expressing bcl-2, none showed a t(14;18) chromosome translocation. These findings may indicate potential mechanisms by which bcl-2 regulates apoptosis.

Base Sequence↗
PubMed1996

Soluble CD44 isoforms in serum as potential markers of metastatic gastric carcinoma.

A splice variant of CD44 (exon V4-V7) confers metastatic behavior in a rat carcinoma model; aberrant expression of splice variants has been detected on a variety of human tumor cell lines as well as primary and metastatic human tumors, including lymphomas, carcinomas (colon, thyroid, mamma, bladder), and glioma. We used enzyme-linked immunosorbent assay to determine the concentration of soluble CD44 in the serum samples of 10 normal individuals and 41 patients with various stages of gastric cancer. Soluble CD44S and its isoforms, V5 and V6, were present in the serum of normal individuals (288.53 +/- 18.33, 25.49 +/- 1.70, and 148.32 +/- 3.15 ng/ml, respectively). The concentrations of soluble CD44 V5 and V6 were elevated in patients with advanced gastric carcinoma (69.39 +/- 6.06 and 216.62 +/- 32.98 ng/ml, respectively). Serum CD44 V5 concentrations correlated with the extent of tumor invasion (T), the status of lymph node involvement (N), and distant metastasis (M) (TNM staging) (p < 0.05), whereas CD44S did not. These results suggest that detection of abnormal regulation of CD44 splicing could be helpful in gastric cancer diagnosis and disease evaluation.

Biomarkers, Tumor↗
PubMed1995

Differential expression of the human metastasis adhesion molecule CD44V in normal and carcinomatous stomach mucosa of Chinese subjects.

BACKGROUND: CD44 is a cell surface adhesion molecule involved in cell-cell and cell-matrix interactions. Tumor cells transfected to overexpress the isoform CD44V readily gain access to lymph nodes and form distant metastases. METHODS: Monoclonal antibodies directed at epitopes common to known CD44 isoforms were used to investigate CD44V expression in 30 normal gastric mucosa tissues, 64 different gastric adenocarcinomas, 20 metastatic adenocarcinoma lymph nodes and 4 established gastric carcinoma cell lines. In addition, CD44V gene expression in six gastric adenocarcinoma tissues and four gastric cancer cell lines were investigated by northern blotting. RESULTS: Immunohistochemistry screening of 30 subjects with normal gastric mucosa did not reveal expression of CD44 variants. Areas of intestinal metaplasia, a precancerous lesion, were stained with antibodies against either V5- or V6-containing isoforms of CD44. Tubular and signet-ring cell types of adenocarcinoma were strongly positive for epitopes encoded by CD44 variants containing exons V5 (41/49 and 10/10, respectively). Some tubular type adenocarcinomas (15/49) also expressed CD44 variants containing the V6 epitope. Tumor differentiation was closely related to CD44 V5 expression (P < 0.001). In addition, 18 of 20 gastric adenocarcinomas metastatic to lymph nodes expressed the V5 epitope of CD44 and 4 of 20 expressed the V6 epitope. Analysis of four established gastric adenocarcinoma cell lines revealed that two had moderate to strong expression of exons V5 and V6 of CD44. An antibody directed against CD44 variants containing exons V8 to V10 strongly stained all gastric adenocarcinoma cell lines. Northern blotting demonstrated that all four tumor cell lines and six gastric carcinoma mucosa tissues expressed CD44V. CONCLUSIONS: Generation of CD44 splice variants may be closely linked with gastric carcinoma tumorigenesis and differentiation. In addition, expression of CD44 variants containing exons V5 and V6 may be used as an indicator of evolving gastric cancer.

Adenocarcinoma↗
PubMed1995

Establishment and characterization of TSGH9201, a human gastric carcinoma cell line that is growth inhibited by epidermal growth factor.

A human signet ring gastric carcinoma cell line TSGH9201 was established in vitro. The cells grew in vitro as a monolayer with polygonal morphology and had a population doubling time of 34 hours. The cells secreted tumor markers CEA and CA 125. They were, however, not tumorigenic in athymic nude mice. Karyotypic analysis demonstrated a near tetraploidy with a modal chromosome number of 98. Northern blotting and immunocytochemical analysis revealed the expression of both transforming growth factor alpha and high levels of epidermal growth factor receptor. Cell growth was inhibited by the epidermal growth factor in vitro. The cell line may be a useful tool to study autocrine growth regulation through the epidermal growth factor receptor.

Animals↗
PubMed1995

Rapid diagnosis of tuberculous meningitis by polymerase chain reaction assay of cerebrospinal fluid.

A polymerase chain reaction (PCR) method for the rapid diagnosis of tuberculous meningitis (TBM) was used to study prospectively 47 cerebrospinal fluid (CSF) samples from 45 patients. Twenty CSF samples were from patients with clinically suspected TBM and another 27 samples came from patients without clinically suspected TBM. Mycobacterial DNA was detected in 15 CSF samples (14 from patients with clinically suspected TBM and 1 from a patient not suspected of having TBM). Of the PCR-positive samples, 4 were also positive for mycobacterial culture. However, 32 PCR-negative samples were all culture-negative. All samples were negative for the acid-fast bacillus by direct smear. The single PCR-positive patient in the clinically unsuspected TBM group was initially diagnosed as suffering from aseptic meningitis on the basis of his clinical features. The mycobacterial culture of his CSF specimen was also positive and a revised diagnosis of an aseptic type of TBM was made. The estimations of specificity and sensitivity in this study were 100% and 70% respectively. The results showed that using a PCR to detect mycobacterial DNA in CSF for the early diagnosis of TBM is not only a rapid but also an accurate method.

Base Sequence↗
PubMed1995

Epstein-Barr virus-associated gastric adenocarcinoma in Taiwan.

Fifty-five gastric carcinoma tumors from Chinese patients in Taiwan, including 40 tubular type (one lymphoepthelioma-like carcinoma subtype), eight signet ring cell type, one papillary type, and six mucinous type gastric carcinomas, were investigated for the presence of Epstein-Barr virus (EBV) transcripts by in situ hybridization using fluorescein-conjugated EBV oligonucleotides for EBERs (Epstein-Barr virus early RNAs) expression and the polymerase chain reaction for viral DNA. Epstein-Barr virus was detected in six of 55 lesions (11%), a significantly lower proportion than has been observed in a North American series. Epstein-Barr virus involvement was more common among male patients. Epstein-Barr virus DNA and its EBERs were specifically present within gastric carcinoma and adjacent dysplastic cells but were absent in surrounding lymphocytes and normal gastric mucosa. Epstein-Barr virus DNA and EBERs were found in one sample of lymphoepithelioma-like carcinoma (LELC) and five specimens of typical gastric adenocarcinoma. Among the EBV-positive gastric adenocarcinomas, four were tubular type of varied differentiation and one was signet ring cell type. Furthermore, we evaluated the expression of the latent membrane protein (LMP) with monoclonal antibodies. We found that LMP was expressed in two EBV-positive samples. In addition, the presence of the EBV receptor was studied by probing samples with CD21 monoclonal antibody. Epstein-Barr virus receptor was not detected in any sample. Southern blot analysis indicated single clonal proliferation of tumor cells. These findings confirm and extend the results of Shibata et al. They also indicate that EBV infection might be related to oncogenesis not only in rare gastric cancers that resemble nasopharyngeal lymphoepithelioma but also in typical gastric adenocarcinoma.

Adenocarcinoma↗
PubMed1995

Application of the polymerase chain reaction to monitor Mycobacterium tuberculosis DNA in the CSF of patients with tuberculous meningitis after antibiotic treatment.

The polymerase chain reaction (PCR) was used to detect Mycobacterium tuberculosis DNA in 29 CSF specimens from seven patients with tuberculous meningitis after the start of antituberculous chemotherapy. Ten of the 13 CSF specimens taken from these patients with an initial treatment of three weeks were positive for the PCR study. By contrast, only one of the other 16 CSF specimens taken from patients treated for more than three weeks was positive. This study shows that M tuberculosis DNA can exist in the CSF of a patient with tuberculous meningitis for three weeks after treatment and that PCR can still be a sensitive method to detect M tuberculosis DNA in the CSF after the start of treatment in patients with tuberculous meningitis.

Adolescent↗
PubMed1995

Evidence that polymorphism of the angiotensin I converting enzyme gene may be related to idiopathic dilated cardiomyopathy in the Chinese population.

Angiotensin I-converting enzyme (ACE) is responsible for the production of angiotension II and the breakdown of kinins, leading to increased blood pressure (BP), induction of vascular smooth muscle cell proliferation, and the stimulation of myocardial-cell hypertrophy. A 287 bp insertion/deletion polymorphism in intron 16 of the ACE gene was examined by polymerase chain reaction in a cross-sectional study of 35 patients with idiopathic dilated cardiomyopathy (IDC) and 35 patients with normally functioning hearts (NT). Compared with the deletion/deletion (D/D) frequency in the control population, the frequency of the deletion allele was 0.757 in IDC patients and 0.600 in NTs; the difference between observed alleles in all subjects in each group was significant (x2 = 3.96; P < 0.05). The data thus provide evidence in favor of an association between idiopathic dilated cardiomyopathy and a polymorphism at the ACE locus (17q23), thus implicating this locus, and possibly a genetic variant of ACE, itself, in human idiopathic dilated cardiomyopathy.

Adult↗
PubMed1995

A young adult with tuberculous meningitis diagnosed by polymerase chain reaction on serial CSF samples: a case report.

A polymerase chain reaction (PCR) assay was used to diagnose a young adult with tuberculous meningitis who presented with unusual clinical symptoms of an acute illness. He had repeated cerebrospinal fluid (CSF) samples taken, and the PCR assay for detecting mycobacterial deoxyribonucleic acid was negative for the first two CSF specimens, but was positive in the third. He was then treated with antituberculous drugs and had complete restoration three months later. A follow-up PCR of the CSF was still positive after one month of therapy using antituberculous drugs, but converted to a negative result one month later. It is concluded that it is valuable to repeatedly sample CSF specimens for PCR study in patients with clinically suspected tuberculous meningitis.

Adult↗
PubMed1994

The variant mRNA isoform of human metastasis gene (CD44V) detected in the cell lines of human hepatocellular carcinoma.

The interaction of the cell surface receptor CD44 molecular with its ligands (addressin, extracellular matrix etc.,) plays an important role in fulfilling the lymphocyte homing and immune reaction. Recently alternatively spliced products of CD44 gene are found to be involved in tumor metastasis as well. Our report found that CD44 prototype RNA (CD44S) was present in all five tumor cell lines. Isoform CD44 RNA (CD44V) was recognized in three metastasized hepatocellular carcinoma cell lines, J5, HCC36, HEP3B. In addition, the J5 CD44 RNA isoform expressed two distinct transcripts which are of the same size as MDA-231 breast tumor cell line. The MDA-231 CD44 RNA variant (CD44V) has been confirmed to contain metastasis domain 4 and 5. It is implicated that the alternative RNA splicing may also play a major role in hepatocellular carcinoma metastasis.

Base Sequence↗