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Biomedical subjects

Z Liao

Publications and source records attributed to Z Liao.

67 records · Page 4Linked to original sources
PubMed1995

Decreased tobacco-glycoprotein-induced lymphocyte proliferation in vitro in pulmonary eosinophilic granuloma.

Pulmonary eosinophilic granuloma is a disorder caused by localized collections of proliferating histiocytes in the lung. Little is known about its etiology except that the majority (58 to 97%) of patients are current or ex-smokers, making the potential etiologic role of tobacco products an important area for research. Tobacco glycoprotein (TGP) is a potent immunostimulator that has been isolated from cigarette smoke. TGP-specific lymphocyte proliferation, and cytokine production in vitro, were measured in three patients with pulmonary eosinophilic granuloma in remission and in three closely matched normal subjects with similar smoking histories. One patient with eosinophilic granuloma of bone and a matched control subject were also studied. Peripheral blood mononuclear cells were cultured with TGP, the recall antigen streptokinase (SK), and the mitogen concanavalin A (Con A). All three of the patients with pulmonary eosinophilic granuloma exhibited significant decreases in lymphocyte stimulation to TGP, despite normal responses to SK and Con A. In contrast, the response of the patient with eosinophilic granuloma of bone was higher than her matched control. The mean responses of the patients with pulmonary eosinophilic granuloma to TGP was significantly lower than the mean of nondiseased smokers or of normal nonsmokers. Twenty-four-hour culture supernatants were collected and assayed for cytokine levels (IL-1, IL-2, and IL-6). TGP-stimulated IL-2 production was significantly lower in the patients with pulmonary eosinophilic granuloma than in the normal subjects, confirming the reduced T-cell proliferative response.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

[Statistical analysis of 4,547 burn patients and the mortality in different periods].

4,547 burn patients from 1983-1993 were reviewed by analysing the general data, mortality, and the causes of the death, and the mortality of 606 burn patients in different periods from 1958 to 1993. The purpose was to present some statistical and epidemiological data. The results showed: The incidence of burn injury in children, whose ages were less than 5 years, reached 36.2%, and the causes of burn was mainly thermal injury. The total mortality was 3.2%, and the main cause of the death was burn wound sepsis. No significant difference in the relationship between the mortality and the burn wound area was observed in these burn patients. In different age groups, the size of III degree burn, which accounted for higher mortality, was much different. The incidence of burn wound sepsis, which was the main cause of mortality, was on the increase, as the analysis of 606 burn patients in four different periods from 1958-1963 showed. In regard to the cure rate, the improvement had not been obvious since 1983.

Adolescent↗
PubMed1994

A study on superoxide dismutase activity of some model compounds.

The synthesis and characteristics of a binuclear ligand N,N,N',N'-tetrakis (2'-benzimidazolyl methyl)-1,4-diethylene amino glycol ether (EGTB) and its series of coordination compounds containing copper(II), iron(III), and manganese(II) with and without exogenous bridging ligand which was imidazolate ion (Im-), bipyridine (bpy), or 1,10-phenanthroline (phen) are reported. Depending on the redox potentials by cyclic voltammetry, the coordination compounds can act as catalysts for the dismutation of superoxide radicals (O2-). The detection of the rate constant of the reaction of superoxide ion with nitroblue tetrazolium (NBT) which is inhibited by superoxide dismutase (SOD) and its model compounds of the EGTB system has been performed by a modified illumination method. The rate constants kQ of the catalytic dismutation have been obtained.

Copper↗
PubMed1994

Objective response of multiple myeloma to cyclosporin A.

Two patients with advanced multiple myeloma were treated with oral low-dose cyclosporin A. one without other therapy and one in conjunction with chemotherapy to which the patient had been previously unresponsive. Both patients had objective laboratory and clinical responses. In the patient treated with cyclosporin A alone, decreasing serum IL-6 and beta-2-microglobulin levels fell as the clinical response evolved. Cyclosporin A deserves further evaluation in the therapy of multiple myeloma.

Administration, Oral↗
PubMed1994

An experimental methodology for the study of postmortem changes in toxic concentrations of drugs, using secobarbital as an example.

Postmortem changes in alcohol and drug concentrations are well known today. The authors used an HPLC assay of barbiturates in postmortem tissue, and developed a rat model in order to evidence postmortem changes in toxics concentrations. Postmortem changes in secobarbital concentrations were evidenced using a rat-secobarbital model. This work emphasizes the difficulty of postmortem toxicology, as concentrations found at the time of autopsy may be different from concentrations at the time of death.

Animals↗
PubMed1993

Increased urine interleukin-1 levels in aging.

Our laboratory previously noted an increase in thymocyte mitogenic activity in the urine of many elderly patients. The present study was performed to verify this finding and to determine if this activity was actually due to an increase in interleukin-1 (IL-1). IL-1 levels were measured in the urine of 33 healthy, ambulatory, elderly subjects (ages 83-95 years), using both a murine thymocyte bioassay, measuring activation by the incorporation of tritiated thymidine and an MTT dye reduction assay. There was a significant increase in urine IL-1 in 85% of elderly individuals. In the MTT dye reduction assay, mean elderly urine IL-1 levels were 0.88 U/ml, in comparison with a young control group (ages 23-37 years) in which urine IL-1 levels were very low (mean IL-1 < or = 0.05 U/ml). Urine levels of IL-1 beta were also measured by using a sensitive immunoassay (ELISA) and were found to be significantly increased in the elderly (mean = 57.4 pg/ml), compared to the young (mean = 2.5 pg/ml). In contrast, IL-2 levels in urine were very low, with no difference between the young and the elderly. Mean urine protein and creatinine levels did not differ significantly between young and old, and did not account for the increase in urine IL-1 levels. Although its immunologic significance is not yet understood, this striking increase in IL-1 is an unusual and interesting finding that merits further investigation.

Adult↗
PubMed1992

Electrocardiographic activity and cardiac function in copper-restricted rats.

The temporal sequence of events leading to cardiac dysfunction during copper restriction in the Long-Evans rat was studied over a 6-week period. Weanling rats were fed either copper-adequate (6 mg Cu/kg diet, n = 25) or copper-restricted (less than 1 mg Cu/kg diet, n = 25) diets for varying periods of time for up to 6 weeks. Beginning at 2 weeks after weaning and weekly thereafter, five rats from each diet were evaluated for cardiac function, and sacrificed, and indicators of copper deficiency were determined on several tissues. Electrocardiograms began showing indications of cardiac disease at Week 3 in the copper-restricted rats, at which time cardiac hypertrophy and other signs of copper deficiency were apparent. Greater QT intervals and QRS amplitudes were observed in copper-restricted rats at various weeks. Peak + and - dP/dt maxs did not differ by diet copper treatment for any of the time intervals studied, nor was any notable difference in developed left ventricular pressure apparent. Hematocrit and liver copper levels were decreased in copper-restricted rat hearts at all weeks. These results suggest that the onset of cardiac dysfunction in copper deficiency is rapid, with both dysfunction and hypertrophy apparent within 3 weeks after copper restriction and when liver copper levels have declined.

Animals↗
PubMed1992

Effects of low copper intake on dimethylhydrazine-induced colon cancer in rats.

Rats fed low copper show a high incidence of dimethylhydrazine (DMH)-induced colon tumors compared with rats fed very high Cu. The difference could be due to Cu deficiency in the low group or to Cu toxicity in the high group. In the present study, rats fed low Cu (0.2 ppm) showed greater DMH-stimulated colon tumorigenesis than rats fed adequate Cu (8 ppm). Differences were seen in the number of rats developing tumors (5 of 11 vs 1 of 10), total tumors (7 vs 2), and average tumor mass (1.02 g vs 0.29 g). Low Cu intake did not cause any general DMH toxicity as assessed by body weight gain. To prevent Cu deficiency-induced mortality, low Cu feeding was begun in postweanling rats (weight, about 80 g) housed in groups of five to six, rather than individually. This limited the effects of low Cu feeding to only a moderate Cu deficiency based on several parameters, including three Cu antioxidant enzyme activities. Group-housed rats fed marginal Cu levels (2.5 ppm) showed normal Cu status, and DMH produced only one tumor in 10 rats. In conclusion, high DMH-induced colon tumorigenesis can be found in rats with low activities of Cu antioxidant enzymes.

Analysis of Variance↗
PubMed1991

Copper deficiency in a genetically hypertensive cardiomyopathic rat: electrocardiogram, functional and ultrastructural aspects.

The effect of copper deficiency on cardiac function and structure was studied in a strain of rats (SHHS/Mcc-cp) known to develop cardiac failure as adults. Restriction of dietary copper (less than or equal to 1 mg/kg vs. 6 mg/kg in adequate diets) at weaning in both sexes for a 6-wk period produced cardiac hypertrophy. Male rats developed more severe copper-deficiency symptoms than their female counterparts. In both sexes of copper-deficient rats, there was an increase in cardiac length, width, free ventricular wall thickness and septum thickness. Electrocardiographic tracings revealed greater QRS height among male copper-deficient rats. Heart rate also was substantially reduced in this group. The increased volume of myocardium occupied by mitochondria in the copper-deficient male rats might result in increased electrical resistance that would increase the QRS height; hypertrophy or anemia also could be contributory. Some male copper-deficient rats had prolongation of the QRS in a bundle branch block pattern. Maximal rates of rise and fall for left ventricular pressure were reduced in male copper-deficient rats. The gross histology indicated that this type of heart failure was more concentric than eccentric. The copper-deficient male rat may serve as a useful model for studying the concentric cardiac hypertrophy that occurs in humans.

Animals↗
PubMed1985

Characterization of a human interleukin 1 inhibitor.

Human urine contains a specific inhibitor of interleukin 1 (IL 1) that is found in increased amounts during fever. This inhibitor was purified by using a sequence of ammonium sulfate fractionation, DEAE cellulose ion-exchange chromatography, molecular sieve chromatography on Sephacryl S-200, affinity chromatography on concanavalin A (Con A) Sepharose, and polyacrylamide gel electrophoresis. Two peaks of IL 1 inhibitory material were eluted from the polyacrylamide gels. One peak contained three proteins of 29, 32, and 67 kd, respectively, which could be visualized by silver staining. The second peak contained only a small amount of the 67 kd protein. A partially purified inhibitor fraction was found to cross-react with antisera directed against two low m.w. urine trypsin inhibitors that are cleavage products of the serum inter-alpha-trypsin inhibitor. Although these findings suggest that the urine IL 1 inhibitor may be related to the inter-alpha-trypsin inhibitor, a more exact identification will require either a homogeneous inhibitor preparation or a monospecific antiserum.

Animals↗
PubMed1984

Identification of a specific interleukin 1 inhibitor in the urine of febrile patients.

The urine of febrile patients has been found to contain high concentrations of an inhibitor of interleukin 1 (IL-1)-induced thymocyte proliferation. The inhibitor is specific for IL-1 and does not block the effects of interleukin 2 (IL-2) or phytohemagglutin (PHA) on thymocytes, and it is not nonspecifically toxic for these cells. IL-1 inhibitor can be found in the urine of normal individuals and afebrile patients, but is present in increased concentrations in the urine of patients with fever of diverse etiologies. Preliminary physicochemical characterization indicates that the inhibitor is a 20-40-kdalton protein.

Animals↗
PubMedDate not supplied

Evaluation of the European Spondyloarthropathy Study Group (ESSG) classification criteria in a Chinese population.

OBJECTIVE: To evaluate for thefirst time in a Chinese population, the usefulness of the European Spondyloarthropathy Study Group (ESSG) criteria. METHODS: A total of 193 clinically diagnosed SpA patients were compared to 166 patients with other types of arthritis, using the parameters listed in the ESSG criteria. RESULTS: The sensitivity and specificity of the ESSG criteria in this Chinese population were high at 85.4% and 96.4% respectively. CONCLUSION: The use of ESSG criteria for classifying SpA in Chinese will not lead to significant omission of SpA patients or inclusion of patients who do not have SpA.

China↗