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Biomedical subjects

T Chen

Publications and source records attributed to T Chen.

At least 415 records · Page 23Linked to original sources
PubMed1982

Limited squamous cell carcinoma of the lung: a Southwest Oncology Group randomized study of radiation with or without doxorubicin chemotherapy and with or without levamisole immunotherapy.

In 1976, the Southwest Oncology Group activated a four-arm randomized study of limited squamous cell carcinoma of the lung. The purpose of this study was to determine if doxorubicin and/or levamisole added to radiation therapy improved the local control rate and survival in patients with limited squamous cell carcinoma of the lung. Of the 107 eligible patients, 15 (14%) had complete responses and 20 (19%) had partial responses. When compared by chemotherapy, immunotherapy, and performance status, no statistically significant difference was found in response rates or in survival. Although not statistically significant, the survival and response rates of patients in the combined levamisole arms were shorter than those of patients in the combined arms not containing levamisole. Patients receiving radiation therapy alone had the best survival. The irradiated field was the site of failure in 68 (88%) of the 77 patients in whom the site of failure was specified. Fifty (65%) of the patients failed in the radiation therapy field only. Chemotherapy and/or immunotherapy as employed in this protocol were of no benefit.

Carcinoma, Squamous Cell↗
PubMed1982

Phase II study of anguidine in gastrointestinal malignancies: a Southwest Oncology Group study.

The Southwest Oncology Group conducted a phase II study of anguidine in 134 patients with gastrointestinal malignancies. Anguidine was administered as a 4-hour infusion at doses of 3.0 and 4.5 mg/m2 daily x 5. Response rates for patients with colon carcinoma were 22% (four of 18 patients without previous chemotherapy) and 6% (four of 63 patients with previous chemotherapy). There were no responses in patients with pancreatic cancer (four patients) or gastric cancer (six). Toxic effects included thrombocytopenia (19.8%), leukopenia (18.8%), nausea and vomiting (49%), hypotension (37%), and confusion (12%). Antitumor activity of anguidine in patients with colon cancer may be similar to that of 5-FU, but nonhematologic toxicity is substantial.

Aged↗
PubMed1981

Elevated vitamin levels in colon adenocarcinoma as compared with metastatic liver adenocarcinoma from colon primary and normal adjacent tissue.

Twenty-four samples of colon adenocarcinoma removed at surgery and autopsy together with adjacent uninvaded normal colon from the same subjects were analyzed for vitamin B12 and B6, biopterin, nicotinate, riboflavin, pantothenate, thiamin, biotin, and folates. Nine specimens of metastatic liver adenocarcinoma from colon primary together with adjacent uninvaded normal liver were also analyzed for these same vitamins. Primary colon adenocarcinoma contains significantly (P less than 0.001) more of the above vitamins than normal colon; 1.8- to 3.5-fold higher concentrations of vitamins were found in this tumor. In contrast, vitamin B12 levels were almost two-fold lower. Unlike colon tumor, metastatic liver adenocarcinoma from colon primary contained from 1.2- to 28-fold lower vitamin concentration than normal liver tissue. The present findings suggest that those types of primary tumors with conspicuously high vitamin content needed for the enhanced growth and catalysis of tumor metabolism may be arrested with antivitamins targeted at metabolic sites other than those involved with nucleic acid synthesis.

Adenocarcinoma↗
PubMed1981

[Comparison of 99mTc-trend scintigraphy and left ventricular angiography in 33 patients (author's transl)].

In 33 patients (30 male, 3 female, mean age 48 years) 99mTc-Trend Scintigraphy (Schad) was compared with left ventricular angiography. 25 patients suffered of a chronic myocardial infarction. In 26 patients complete or partial agreement between the two methods was seen. The scintigraphy showed false negative results in the apical region and false positive results in the basal segments. The comparison of both methods shows that 99mTc-Trend Scintigraphy can be used to evaluate non-invasively the function of the left ventricle.

Coronary Vessels↗
PubMed1981

Ethanol and cell replication in the digestive tract.

Ethanol-induced injury of the intestines, liver and pancreas evokes a regenerative response which is characterized by a series of morphological and biochemical adaptive responses in subcellular organelles, and an increase in chromosomal protein and DNA replication. Patterns of cell replication vary with the system involved, the amount of injury and the presence of essential precursors or catalysts needed for cell replication. Maintenance of normal cell replacement patterns in the digestive tract of the alcoholic requires correction of deficits and interruption of alcohol intake. An inadequate or excessive regenerative response is of key importance in perpetuating tissue injury in the alcoholic. Regenerative capacity has been evaluated in man by measurement of circulating levels of CEA and alpha-fetoprotein; unfortunately, there is often no correlation between cell replication and these parameters in the malnourished alcoholic. Studies of mitoses or organelle changes in biopsies of intestines and liver are valuable; however, accurate monitoring of regeneration is possible only by kinetic studies utilizing incorporation of tritiated thymidine into DNA.

Alcoholism↗
PubMed1981

Use of glycopyrrolate in the parturient: effect on the maternal and fetal heart and uterine activity.

The effects of intravenous glycopyrrolate on maternal and fetal heart rate, heart rate variability, and maternal electromechanical intervals and blood pressure were evaluated in 20 term parturients in labor. Direct continuous fetal heart rate and intrauterine pressure were monitored via an intrauterine catheter. Maternal heart rate and R-pulse-wave intervals were measured and maternal blood pressure was recorded at 5-minute intervals. There were no significant changes in fetal heart rate or fetal heart rate variability. The maternal heart rate increased in all cases and the electromechanical interval decreased with the onset of maternal tachycardia. There were no significant changes in maternal blood pressure. Uterine activity increased in all cases; however, this increase does not appear to be greater than that expected in uterine activity as labor progresses.

Blood Pressure↗
PubMed1980

Demonstration of 1,25-dihydroxyvitamin D3 receptors in human skin biopsies.

In this study we report the demonstration of receptors for 1,25-(OH)2 vitamin D3 in fresh and cultured human skin. Cultured fibroblasts grown from infant foreskin exhibit a binding site which by Scatchard analysis had a Kd for [3H]1,25-(OH)2D3 of 0.2 nM and an Nmax of approximately 40 fmol/mg cytosol protein. On sucrose density gradients the receptor sediments at 3.2S. Receptors could also be identified in skin biopsies from adult patients when assayed either in fresh epidermis or cultured keratinocytes and dermal fibroblasts. The human receptors are similar to rodent receptors assessed in classical target organs such as intestine, bone and kidney. The findings that receptors can be measured in cultured human skin after several arterial passages indicates that skin biopsy may provide a means of assessing the 1,25-(OH)2D3 receptor status of patients.

Adult↗
PubMed1980

Pulmonary manifestations of vinyl and polyvinyl chloride (interstitial lung disease). Newer aspects.

Newer varieties of occupational lung diseases primarily due to the vast increase in industrial technology have been reported recently. Preeminent among such newer agents are vinyl chloride (VC) and polyvinyl chloride. Very few cases have been reported, in Europe only, with descriptive histopathologic changes. To our knowledge, no pathologic studies of VC exposure have been described in the American literature. The biopsy abnormalities in our patients disclosed desquamation of alveolar macrophages into the alveolar lumina and minor interstitial and alveolar inflammatory changes. Pulmonary function abnormalities included restrictive insufficiency. Preventive therapy consists of the avoidance of further exposures, frequent industrial hygiene monitoring, and total avoidance of tobacco smoke, as well as associated atmospheric pollutants. Thus far, none of these patients has exhibited evidence of pulmonary neoplasms. All three patients survived their occupational injuries, and two are still disabled to varying degrees. Urine and blood levels of phthalic acid derivatives were elevated in two patients, the exact significance of which is not fully known. It probably represents a toxicologic response, but must be further pursued before conclusions can be reached.

Adult↗
PubMed1980

[Myocardial scintigraphy (thallium-201) and electrocardiography at rest and during exercise in angina pectoris. A comparison with coronary angiography (author's transl)].

Ecg (at rest and during exercise) was compared to Thallium-201 myocardial perfusion imaging (at rest and after exercise) in 65 patients with coronary heart disease (myocardial infarction in 53 patients) and angina pectoris. These results were compared to coronary angiography and left ventricular angiography. Group I: (48 patients, comparison of Ecg at rest and Thallium-201 imaging at rest): 33 patients showed agreement of results. In comparison to angiography the 201-Thallium imaging showed less false-negative results than the Ecg as rest. Group II: (23 patients, comparison of Ecg during exercise with Thallium-201 imaging after exercise): 8 patients showed agreement, 15 patients did not. In comparison to angiography the imaging showed better agreement in 20 of 23 patients, the exercise Ecg in 14 of 23 patients. Exercise-Ecg showed false-negative results in 7 patients, Thallium-201 imaging in none. Especially in 1-vessel-disease imaging was superior. Group III: (24 patients, comparison of Ecg at rest and during exercise to 201-Thallium at rest and after exercise): In 19 patients results agreed almost. Because of background-correction imaging is inferior to the Ecg in the apical region. Imaging is superior to the Ecg in the septal and inferior-myocardial regions. Combination of both methods gives best correlations. Sensitivity of Ecg-results is 77% and in imaging 93%.

Adult↗
PubMed1978

In vitro interaction of L1210 cells with phospholipid vesicles.

The in vitro uptake of phospholipid vesicles by mouse leukemia L1210 cells was examined. Liposomes were generated by prolonged ultrasonic dispersion of aqueous dispersions of mixed lipids in the presence of radiolabeled inulin. Multilamellar vesicles were separated from unilamellar vesicles by column chromatography. Vesicle populations were examined by electron microscopy. Neutral vesicles were generated from egg yolk phosphatidylcholine and cholesterol, and surface charge was introduced via either phosphatidylserine or octadecylamine. Uptake, measured as cell-associated radioactivity, was temperature dependent and was strongly decreased by metabolic inhibitors. These results suggested that liposomes are taken up to a major extent by an energy-dependent mechanism. The uptake of liposomes by cells of a young culture was about 2-fold higher than was the uptake of liposomes by cells of a stationary culture. The uptake of positively charged liposomes by cells was about 20-fold higher than that of either neutral or negatively charged vesicles. About one-half of the cell-associated radioactivity transferred by positively charged liposomes could be removed by cell surface treatment with trypsin or neuraminidase or by a short exposure to 0.6 N NaCl.

Animals↗
PubMed1977

Alcoholic hyalin antigen (AHAg) and antibody (AHAb) in alcoholic hepatitis.

Complement fixation (CF) and immune adherence (IA) hemagglutination tests demonstrate antigen (Ag) and antibody (Ab) to alcoholic hyalin (AH) in serum of patients with alcoholic hepatitis. Immunoglobulins from postmortem liver of patients dying of alcoholic hepatitis show antibody activity against AH. Isolated purified AH was used to produce AHAb in rabbits. Rabbit antiserum was added to heat-inactivated human serum to detect AHAg; purified AH was added to serum and tissue elutes to detect AHAb. AHAg was present in serum of each of 15 patients with early phase alcoholic hepatitis in CF titers of 8 to 64 and IA titers of 16 to 2048. AHAg became negative within 3 to 5 weeks with abstinence from alcohol and was followed by transient appearance of AHAb. AHAb was present in 11 patients with advanced phases of alcoholic hepatitis in CF titers of 8 to 640 and IA titers of 16 to 4096. Four patients in this group exhibited concomitant AHAb and AHAg. Investigations of liver tissue elute reveal that patients with advanced alcoholic hepatitis or active alcoholic cirrhosis have AHAg-reactive immune complexes containing IgG and IgA immunoglobulins.

Animals↗
PubMed1976

Lymphocyte proliferation inhibitory factor (PIF) in alcoholic liver disease.

Lymphocyte proliferation inhibitory factor (PIF) was determined in the supernatants of PHA-stimulated lymphocytes from patients with alcoholic liver disease. PIF was assayed by determining inhibition of DNA synthesis in WI-38 human lung fibroblasts. A two-fold greater inhibition in thymidine incorporation into DNA by lung fibroblasts was observed in supernatants of PHA stimulated lymphocytes from patients with alcoholic hepatitis or active Laennec's cirrhosis as compared with that found in control subjects or patients with fatty liver. It is suggested that decreased liver cell regeneration seen in some patients with alcoholic hepatitis may be due to increased elaboration of PIF.

Alcoholism↗