Biomedical subjects

H Ren

Publications and source records attributed to H Ren.

At least 163 records · Page 9Linked to original sources

PubMed1993

[Evaluation of local resection for primary tracheal tumor: a clinical analysis of 23 cases].

During a 17 year period, 23 patients with primary tracheal tumor underwent surgery in the PUMC Hospital. Of them, 11 cases were benign tumors and 12 had low malignancies. 11 patients with benign tumors received 14 times of apoxesis of the tumor. 12 cases with low malignancies underwent 15 times of operations including local resection of the tracheal wall and tumor in 4 cases, and tumor apoxesis as well as electrocautery on the basis in 10 cases. Eight of 9 patients with adenoid cystic carcinoma were treated postoperatively with irradiation. Eleven cases with benign tumors were followed up for an average 6.3 of years. Nine cases with adenoid cystic carcinoma were followed up for an average 7.6 of years and 5 year survival rate was 75% (6/8). Among them 3 cases survived longer than 10 years. The authors consider that the local resection and tumor apoxesis can yet be regarded as a simple and effective way of surgical treatment for primary tracheal tumor.

Adolescent↗

PubMed1993

Thymic carcinoid tumor--a report of 7 cases.

The thymic carcinoid tumor is a rare neoplasm which is often clinically misdiagnosed as thymoma. But the two differ in origin, biological behavior, accompanying syndromes, pathological features, and prognosis. The characteristics of the thymic carcinoid tumor are: difficulty in diagnosis, high malignancy, frequent recurrence and extrathoracic metastasis over a prolonged period postoperatively. Complete surgical resection of original and recurrent tumors is the important treatment. Microscopic, electron microscopic and immunohistochemical examinations may be required in making an accurate pathological diagnosis. This paper reports 7 cases of thymic carcinoid tumor.

Adult↗

PubMed1993

Misdiagnosis of lung cancer in patients under age 40--a clinical analysis of 47 cases.

Diagnosis of lung cancer in 47 patients aged younger than 40 years was delayed as a result of misdiagnosis, accounting for 70.1% of all cases of lung cancer in those aged less than 40 years treated in PUMC Hospital in the same period. Pulmonary tuberculosis and tuberculous pleurisy were diagnosed in 26 cases (55.3%). Pulmonary inflammation was suspected in 24 cases (51.1%). The delay in diagnosis was one to three months in 28 cases and longer than 3 months in 19 cases. Twenty-eight (59.6%) of the 47 patients underwent surgery, including exploratory thoracotomy (21.4%) and pneumonectomy (40.9%). The five-year survival rates in the resectable group and in the non-surgical group were 31.6% and 5.3%, respectively. We recommend that accessory examinations should be performed wherever possible in younger patients with suggestive pulmonary nodules in order to collect sufficient evidence to confirm or rule out the diagnosis of lung cancer and thereby reduce the rate of misdiagnosis in such younger people.

Adenocarcinoma↗

PubMed1993

Apoxesis of primary tracheal tumor. A clinical analysis of 23 cases.

During a 17-year period, 23 patients with primary tracheal tumors underwent surgical treatment in the Department of Thoracic Surgery, PUMC Hospital (11 cases of benign tumor of the trachea, 12 cases of low malignancies). Fourteen times of apoxesis were performed in 11 patients with benign tumors who were followed up for an average of 6.3 years. Fifteen operations were performed in 12 cases including local resection of the tracheal wall and tumor in 4, and curettage of tumor plus electric cauterization on the basis in 10. Eight of 9 patients with adenoid cystic carcinoma received postoperative adjuvant irradiation, with a 5-year postoperative survival rate of 75% (6/8) and 3 cases survived over ten years. The desirability of apoxesis and local resection of tracheal tumor is discussed. The authors suggest that these two surgical patterns can be regarded as a simple and effective treatment for patients with primary tracheal tumors.

Adolescent↗

PubMed1993

Serum tumor necrosis factor (TNF) in the pathogenesis of clinical hepatic failure of HCV and/or HBV infection.

Serum TNF and IL-6 levels were measured in 48 patients with liver disease positive for anti-HCV only or concurrent HBV infection. High serum TNF levels were observed in patients with liver disease positive for anti-HCV and/or HBV infection (P < 0.001). Serum TNF levels varied with the severity of liver disease. Serum TNF levels of anti-HCV positive patients with hepatic failure were higher than those with CAH (P < 0.01). Serum TNF levels of patients infected with HCV or concurrent HBV were also significantly higher than those with HBV infection alone (P < 0.001). However, no difference in serum IL-6 levels was observed in either group of patients. Serum TNF in the deceased patients with hepatic failure induced by HBV and HCV infection was higher than in those who survived (P < 0.05), and it also seemed significantly different in patients with and without multiple organ failure (P < 0.05). In vitro, HSS showed marked inhibitory activity on TNF production from PBM induced by endotoxin, but had no significant effect on the TNF cytotoxicity of L929 cells. It seems that high serum TNF level is an important mediator in the pathogenesis of liver necrosis and failure of microcirculation in HCV and/or HBV infection. These observations favor the attempt to treat hepatic failure with HSS or anti-TNF. Encouraging results were achieved using HSS in the treatment of subacute liver necrosis in our institute.(ABSTRACT TRUNCATED AT 250 WORDS)

Enzyme-Linked Immunosorbent Assay↗

PubMed1993

Hepatitis B virus infection in Honolulu students.

OBJECTIVES: To determine hepatitis B virus (HBV) carrier and infection rates and HBV epidemiology in Honolulu students. DESIGN: Cross-sectional survey. SETTING: Honolulu public elementary, intermediate, and high schools. PATIENTS: A volunteer sample of 4936 students from 43 Honolulu schools. MAIN OUTCOME MEASURES: HBV carrier rate (presence of hepatitis B surface antigen) and infection rate (presence of either hepatitis B surface antigen, antibody to hepatitis B surface antigen, antibody to hepatitis B core antigen, or any combinations of these) by school grade, ethnicity, and place of birth. RESULTS: Eighty-three (1.68%) students were identified as HBV carriers, and a total of 353 (7.15%) students had serologic evidence of infection. Infection rates increased from elementary school age to high school age, more so in Asian/Pacific Island-born students. The prevalence of infection was higher in Asian/Pacific Island-born students than in those born in the United States. The majority of infected Hawaiian-born students were first-generation Asian/Pacific Island Americans. CONCLUSIONS: Horizontal transmission of HBV occurs in Honolulu school-age children. HBV immunization of all infants in Hawaii, not just those born to carrier mothers, is necessary to reduce HBV transmission in Hawaii.

Adolescent↗

PubMed1993

Long survival with giant cell myocarditis.

Several aspects of giant cell myocarditis remain controversial, including the natural history of the disease and the nature of the giant cells. We have observed three patients who had long survival with chronic active giant cell myocarditis. The first patient was a 59-yr-old female who had a 10-yr history of complete heart block which was found at autopsy to have been caused by giant cell myocarditis. The second patient is a 36-yr-old female who received a heart transplant 5 yr after a biopsy proven episode of active myocarditis, and examination of the explanted heart revealed giant cell myocarditis. The third patient was a 41-yr-old male who received a heart transplant 2 yr after developing progressive heart failure, and the explanted heart had giant cell myocarditis. On immunohistochemical study of the three hearts, the giant cells stained with the macrophage markers lysozyme and KP-1 (CD-68). Staining of the same cells with desmin and actin was focally positive in a punctate pattern, correlating with the ultrastructural presence of myofibrils within giant cell phagolysosomes. The associated lymphocytic infiltrate stained primarily for the T-cell markers CD-3, CD-45RO, and CD-43 whereas only a few of the lymphocytes stained with the B-cell marker CD-20. The long histories of cardiac dysfunction in the three patients show that giant cell myocarditis may have a protracted course. The morphologic studies show that the giant cells are of histiocytic origin but can contain phagocytosed components of myocytes, observations that may account for the controversy surrounding the nature of the giant cells in giant cell myocarditis.

Adult↗

PubMed1992

Cloning, expression, and characterization of the unique bovine A1 adenosine receptor. Studies on the ligand binding site by site-directed mutagenesis.

The bovine brain A1 adenosine receptor (A1AR) is distinct from other A1ARs in that it displays the unique agonist potency series of N6-R-phenylisopropyladenosine (R-PIA) greater than N6-S-phenylisopropyladenosine (S-PIA) greater than 5'-N-ethylcarboxamidoadenosine and has a 5-10-fold higher affinity for both agonists and antagonists. The cDNA for this receptor has been cloned from a size-selected (2-4-kb) bovine brain library and sequenced. The 2.0-kb cDNA encodes a protein of 326 amino acid residues with a molecular mass of 36,570 daltons. The amino acid sequence fits well into the seven-transmembrane domain motif typical of G protein-coupled receptors. Northern analysis in bovine tissue using the full length cDNA demonstrates mRNAs of 3.4 and 5.7 kb with a tissue distribution consistent with A1AR binding. Subcloning of the cDNA in a pCMV5 expression vector with subsequent transfection into both COS7 and Chinese hamster ovary cells revealed a fully functional A1AR which could inhibit adenylylcyclase and retained the unique pharmacologic properties of the bovine brain A1AR. The A1AR was found to have a single histidine residue in each of transmembrane domains 6 and 7. Histidine residues have been postulated by biochemical studies to be important for ligand binding. Mutation of His-278 to Leu-278 (seventh transmembrane domain) dramatically decreased both agonist and antagonist binding by greater than 90%. In contrast, mutation of His-251 to Leu-251 decreased antagonist affinity and the number of receptors recognized by an antagonist radioligand. In contrast, agonist affinity was not perturbed but the number of receptors detected by an agonist radioligand was also reduced. These data suggest that both histidines are important for both agonist and antagonist binding, but His-278 appears critical for ligand binding to occur.

Adenylyl Cyclase Inhibitors↗

PubMed1992

A study of the effect of magnetized water on enzyme activities by potentiometric enzyme electrode method.

A very promising glutamate decarboxylase electrode, which has linear response range of 5.6 x 10(-5)-1.2 x 10(-2) mol/L. Nernstian slope of 50 mV/decade, detection limit of 3.2 x 10(-5) mol/L and response time less than 3 min, has been designed to observe and evaluate quantitatively the effect of magnetized water on enzyme activities by potentiometric enzyme electrode method. It was found that the activity of glutamate decarboxylase can increase by 30% in magnetized water. The mechanism of increased enzyme activity was discussed in the present paper. Such a new finding will probably lead to some new explanations for the physiological and biological mechanism of the effect of magnetized water on living organisms, thus providing a new approach to the study of the effect of magnetized water.

Electrodes↗

PubMed1992

[Tumor necrosis factor and interleukin 6 in hepatitis C virus infection].

Tumor necrosis factor (TNF) was determined with ELISA in 72 patients with hepatitis C and hepatitis B virus infections. Interleukin 6 (IL-6) was determined at the same time. TNF and IL-6 were significantly increased in patients with hepatitis C virus infections when compared with normal subjects and hepatitis B patients. There was a significant positive correlation between TNF and IL-6. It is suggested that increased TNF and IL-6 may play an important role in pathogenesis of hepatitis C virus infection.

Adult↗

PubMed1992

[Effect of compound and minor prescription of heat-nature products radix Aconiti lateralis preparata, rhizoma Zingiberis and cortex Cinnamomi on the sympathetic nervous system, adrenal gland, TSH and LH].

The effect of compound and minor prescriptions of Radix Aconiti Lateralis Preparata, Rhizoma Zingiberis and Cortex Cinnamomi on sympathetic nervous system, adrenal gland, TSH and LH of rats was studied. Results showed that both prescriptions made the heart rate quicken, estrous cycle shorten, improved the adrenal cortex hormone and promote TSH and LH synthesis and secretion. The two Heat-nature products (Radix Aconiti Praeparata and Rhizoma Zingiberis) may be used instead of all the three products to make a Heat Syndrome animal model.

17-Hydroxycorticosteroids↗

PubMed1992

[Hepatocyte stimulatory peptide and its clinical significance in viral hepatitis].

Hepatocyte stimulator peptide (HSP) is a new hepatic stimulator substance. Its monoclonal antibodies have been obtained in our laboratory. In this study, HSP was determined in the sera of 315 subjects including patients with various forms of hepatitis and healthy persons with enzyme-linked immunosorbent assay (sandwich method). It is shown that HSP level in the sera of patients with fulminant hepatitis was high and correlated with the level of tumour necrosis factor (TNF), serum bilirubin (SB) or prothrombin time (PT). It is suggested that level of HSP in the sera of the patients reflected the degree of hepatocyte injury. A formula was recommended to predict the outcome of the patients with fulminant hepatitis.

Enzyme-Linked Immunosorbent Assay↗

PubMed1992

The effect of multi-glycosides of Tripterygium wilfordii Hook f. (GTW) on the survival time of cardiac allografts in rats.

Heterotopic heart transplantation was carried out in rats and the influence of multi-glycosides of Tripterygium wilfordii Hook f. (GTW) and a subtherapeutic dose of cyclosporine A (CsA) on the mean survival time (MST) of the cardiac allografts was investigated. The results showed that the MSTs of cardiac allografts in both the GTW and CsA-treated groups were significantly prolonged (P < 0.01 vs control). The rate of allograft rejection in the drug-treated groups was much lower than that in the control group.

Abdomen↗

PubMed1992

[Primary pulmonary chemodectoma. Report of 2 cases and review of the literature].

The authors report two cases of primary pulmonary chemodectoma. The patients were admitted to the PUMC Hospital because of nodular lesion in the lung. The diagnosis was documented by postoperative pathology. Primary pulmonary chemodectoma is rare. Ten cases has been reported in the English literature. The clinical characteristic features is pulmonary single lesion on chest X-ray film. No correct diagnosis was made pre-operatively. A typical histopathological finding is observed. NSE and S-100 proteins is positive with immuno-histological stain. Surgery operation is the only reliable treatment.

Diagnostic Errors↗

PubMed1991

A PCR procedure to determine the sequence of large polypeptides by rapid walking through a cDNA library.

A procedure that uses the PCR to make rapid successive steps through a random-primed cDNA library has been developed to provide a method for sequencing very long genes that are difficult to obtain as a single clone. In each successive step, the portions of partial clones that extend out from the region of known DNA sequence are amplified by two stages of PCR with nested, outward-directed primers designed approximately 50 bases in from the end of the known sequence, together with a general primer based on the sequence of the vector. This procedure has been used to determine the coding sequence of the cDNA for the beta heavy chain of axonemal dynein from embryos of the sea urchin Tripneustes gratilla. By starting from a single parent clone, whose translated amino acid sequence overlapped the microsequence of a tryptic peptide of the beta heavy chain, and making 3 such walk steps downstream and 14 walk steps upstream, we obtained a sequence of 13,799 base pairs that had an open reading frame of 13,398 base pairs. This sequence encodes a polypeptide with 4466 residues of Mr 511,804 that is believed to correspond to the complete beta heavy chain of ciliary outer arm dynein.

Amino Acid Sequence↗

PubMed1991

Prevention of syngeneic graft-versus-host disease by recovery of thymic microenvironment after cyclosporine.

Following a course of cyclosporine, syngeneic rat radiation chimeras consistently develop a GVHD-like syndrome. Correlation of the thymic immunopathology with conditions leading to syngeneic graft-versus-host disease (sGVHD) suggested the hypothesis that reconstitution of the normal thymic microenvironment after CsA is necessary for self-tolerance. When thymic regeneration is impaired, as in rats receiving previous mediastinal irradiation, then self-reactive effector cells are not regulated and proceed to damage the target tissues. Alternately, it could be argued that the observed thymic abnormalities are irrelevant to sGVHD. To test the primary hypothesis, post-CsA thymic reconstitution was prevented by total thymectomy in unirradiated rats. These rats consistently developed acute type sGVHD seen at 7 and 21 days post-CsA while rats from the CsA-treated sham thymectomy control group failed to develop sGVHD. Because thymectomy prior to CsA blocks sGVHD, most likely the peripheral effector cells in the post-CsA thymectomy group were derived from the CsA-altered thymus. The absence of sGVHD in the sham group indicates that the thymus led to active regulation of these cells after stopping CsA. If regeneration of the thymus restored only negative selection, then the sham thymectomy group should have also developed sGVHD. Flow cytometry and morphology of the spleen and lymph nodes demonstrated that the thymectomized rats, like CsA-treated radiation chimeras, experienced a significant delay in maturation of T cells following CsA. In contrast to the usual model in radiation chimeras, however, the post-CsA thymectomized rats did not convert to chronic type sGVHD. The importance of an abnormal thymus for this transition was confirmed in syngeneic radiation chimeras. Thymectomy after CsA in these rats also blocked the rapid transition to chronic sGVHD.

Acute Disease↗

PubMed1991

Treatment of small cell lung cancer.

During a 28-year period, 110 patients with small cell lung cancer were treated at our hospital. Fifty-nine patients received surgery, and 58 patients (including 7 cases after exploratory thoracotomy) received chemotherapy and/or radiotherapy. The 5-year survival rate of the surgically treated group was 17%, while none in the non-surgical group survived for more than 5 years.

Adult↗

PubMed1991

Midazolam as a main anesthesia induction agent--a comparison with thiopental and diazepam.

A clinical randomized investigation was undertaken to determine the value of midazolam as a narcotic adjuvant for anesthetic induction. Thirty ASA I-II adult patients undergoing selective surgery were allocated randomly into two groups to receive one of the following agents: midazolam 0.3 mg/kg, thiopental 5 mg/kg, or diazepam 0.4 mg/kg. The induction time as measured from the onset of injection to loss of the eyelash reflex was shortest in the case of thiopental; while a lower frequency of apnea, lesser suppression of circulation, and lack of venous irritation were points favoring midazolam. However, further study is needed to clarify the moderate cardiovascular response seen during intubation in some cases as well as to elucidate any patient population differences.

Adams-Stokes Syndrome↗