Biomedical subjects

T F Wang

Publications and source records attributed to T F Wang.

At least 37 records · Page 2Linked to original sources

PubMed1997

Gall-bladder wall thickening in patients with liver cirrhosis.

Gall-bladder wall thickening is commonly seen in patients with cirrhosis, but its exact causes have not been well established. We evaluated clinical, biochemical and haemodynamic data of patients with cirrhosis with respect to the presence of thickening of the gall-bladder wall. After excluding patients who presented with gallstones, acute or chronic cholecystitis, heart failure, a serum creatinine level greater than 2 mg/dL and/or a serum alanine aminotransferase level greater than 400 U/L, 77 patients with cirrhosis (75 male, two female; mean age 58 +/- 8 years) were enrolled in the study. Clinical, biochemical, ultrasound and haemodynamic data were obtained in every patient. Forty-one (53%) of 77 patients with cirrhosis had gall-bladder wall thickening (> 4 mm). Compared with patients with a normal gall-bladder wall, patients with gall-bladder wall thickening had significantly lower serum albumin levels (3.6 +/- 0.6 vs 2.9 +/- 0.7 gm/dL, respectively; P < 0.05), a longer prothrombin time (13 +/- 6 vs 16 +/- 6 s, respectively; P < 0.05), more patients with Child-Pugh class C (6 vs 37%, respectively; P < 0.05) and more patients with ascites (8 vs 50%, respectively; P < 0.05). In addition, compared with patients with a normal gall-bladder wall, those patients with gall-bladder wall thickening had a higher hepatic venous pressure gradient (13.9 +/- 4.5 vs 17.1 +/- 4.1 mmHg, respectively; P < 0.01) and a lower systemic vascular resistance (SVR; 1144 +/- 332 vs 1010 +/- 318 dyn.s/cm5, respectively; P < 0.05). Using a multivariate analysis, the presence of ascites and SVR lower than 900 dyn.s/cm5 were independently correlated with the presence of gall-bladder wall thickening, while a hepatic vein pressure gradient greater than 10 mmHg had only a marginally significant association. The presence of ascites, decreased SVR and portal hypertension are related to the occurrence of gall-bladder wall thickening in patients with cirrhosis, indicating that the development of gall-bladder wall thickening may be multifactorial.

Ascites↗

PubMed1996

CD39 is an ecto-(Ca2+,Mg2+)-apyrase.

CD39, a 70- to 100-kDa molecule expressed primarily on activated lymphoid cells, was previously identified as a surface marker of Epstein Barr virus (EBV)-transformed B cells. In this report, we show that an ecto-(Ca2+,Mg2+)-apyrase activity is present on EBV-transformed B cells, but not on B or T lymphomas. The coincidence between CD39 expression and ecto-apyrase activity on immune cells suggests that CD39 may be an ecto-apyrase. This supposition is supported by the observation that the amino acid sequence of CD39 is significantly homologous to those of several newly identified nucleotide triphosphatases. Finally, we show that CD39 indeed has ecto-apyrase activity by expression in COS-7 cells.

Adenosine Triphosphatases↗

PubMed1996

Plasma interleukin-8 levels in patients with post-hepatitic cirrhosis: relationship to severity of liver disease, portal hypertension and hyperdynamic circulation.

The present study investigated plasma levels of interleukin-8 (IL-8) in patients with post-hepatitic cirrhosis and correlated it with the severity of liver diseases and haemodynamic parameters. Plasma IL-8 levels were significantly higher in 57 post-hepatitic cirrhotic patients (7.5 +/- 1.8 pg/mL; P < 0.005) than those in 41 healthy subjects (2.0 +/- 0.2 pg/mL). Elevated (> 5 pg/mL) plasma IL-8 levels were found in up to 30% of cirrhotic patients. In cirrhotic patients, plasma IL-8 levels progressively increased in relation to the severity of liver dysfunction (4.5 +/- 1.0, 4.9 +/- 1.4 and 20.5 +/- 8.3 pg/mL for Pugh's class A, B and C, respectively; P < 0.005). A significant correlation was observed between plasma IL-8 levels and serum bilirubin levels (r = 0.72; P < 0.001). There were no differences in the hepatic venous pressure gradient (15.4 +/- 1.1 vs 15.1 +/- 0.9 mmHg; P > 0.05) and systemic vascular resistance (1119 +/- 118 vs 1199 +/- 54 dyn.s/cm5; P > 0.05) between cirrhotic patients with and without elevated plasma IL-8 levels. In addition, plasma IL-8 levels did not correlate with hepatic venous pressure gradient (r = 0.26; P > 0.05) and systemic vascular resistance (r = -0.24; P > 0.05). These results demonstrate that plasma IL-8 levels are increased in patients with post-hepatitic cirrhosis. The severity of liver cirrhosis is an important factor for the occurrence of enhanced IL-8 levels. IL-8 does not play a role in the hyperdynamic circulation observed in patients with post-hepatitic cirrhosis.

Bilirubin↗

PubMed1995

Generation of cytotoxic effector cells against human melanoma.

Metastatic or tumor-draining lymph nodes from six of nine melanoma patients undergoing lymph node dissection for metastatic melanoma generated cytotoxic T cells against autologous melanoma when these lymph node cells were treated by in vitro sensitization and recombinant interleukin-2 (IL-2). During the initial lymphocyte culture (2-6 weeks), cross-reactivity with autologous tumor cells, K562 and Daudi cells was usually noted. Cold-target inhibition assay with K562 and Daudi showed K562/Daudi-associated antigens on melanoma cells. During the later phase of lymphocyte culture with repeated in vitro sensitization (over 6-10 weeks), cytotoxicity was noted against autologous and allogeneic melanoma cells but not against K562. Daudi cells or autologous fibroblasts. Repeated in vitro sensitization resulted in the selection of specific cytotoxic lymphocytes against melanoma. Cold-target inhibition assay with autologous and allogeneic melanoma cells revealed shared and individual antigens. Using blocking monoclonal antibodies, MHC-restricted killing was noted in the autologous system. Further, both the autologous and allogeneic systems could be mediated through adhesion molecules such as ICAM-1 and LFA-3 on melanoma cells and LFA-1 on T cells. This study suggests that a constellation of cytotoxic effector cells and melanoma-associated antigens may be pivotal in tumor killing. Thus, future adoptive immunotherapy should modulate and enhance this complex interaction.

Adult↗

PubMed1995

Eosinophil differentiation and hypodensity alteration activities in Dermatophagoides pteronyssinus-stimulated mononuclear cell culture supernatants derived from asthmatics.

We investigated the contributing effect of Dermatophagoides pteronyssinus-stimulated mononuclear cell (MNC) cultured supernatants on the differentiation and density alteration of eosinophils. MNC, obtained from either normal subjects or asthmatics, were cultured with or without D. pteronyssinus. The supernatants were tested for the activity of eosinophil differentiation and density alteration. The results showed a significant increase in eosinophil differentiation activity in D. pteronyssinus-stimulated MNC supernatants of asthmatics when compared with normal subjects. This activity can be blocked by anti-IL-5 antibodies. Eosinophil hypodensity change was also noted after treatment with D. pteronyssinus-stimulated MNC supernatants or IL-5, but not after D. pteronyssinus treatment. In conclusion, MNCs, activated by D. pteronyssinus, might contribute to the eosinophil differentiation and hypodensity change in asthmatics.

Allergens↗

PubMed1995

The modulatory effect of tetrandrine on the CD23, CD25 and HLA-DR expression and cytokine production in different groups of asthmatic patients.

The therapeutic effect and mechanism of action of tetrandrine on asthma are not defined. Recently, it has been proposed that mononuclear cell (MNC) infiltration in the airway plays a role in the pathogenesis of asthma. In this study, we evaluated the effect of tetrandrine on the cell receptor expression and cytokine production of MNC from two groups (young atopic and old non-atopic) of stable asthmatic patients. MNC separated from peripheral blood of both asthmatic patients and normal individual were cultured in serum free RPMI-1640, with or without phytohemagglutinin (5 micrograms/ml) and tetrandrine (2 micrograms/ml). After culture, MNCs were harvested and stained with monoclonal antibodies for HLA-DR, CD23, CD25 and CD3. MNC supernatants were collected for the measurement of IL-2, IL-4 and interferon-gamma (IFN-gamma). The results show that tetrandrine may inhibit (1) MNC proliferation, (2) the production of IL-2, IL-4 and IFN-gamma, and (3) the expression of HLA-DR, CD23 and CD25 on CD3 positive T cells. They were inhibited to a similar extent in both groups of asthmatic patients. These results suggest that tetrandrine might have some therapeutic role in relation to the suppression of lymphocyte function in asthmatics.

Adult↗

PubMed1994

Liposuction-derived human fat used for vascular graft sodding contains endothelial cells and not mesothelial cells as the major cell type.

PURPOSE: Endothelial cell transplantation has been suggested as a method to improve the patency of prosthetic grafts used for vascular reconstruction. A major technical concern of all cell transplantation studies has been the purity of cells in the primary isolate used for subsequent transplantation. Accordingly we have evaluated the cellular constituents of liposuction-derived human fat with immunocytochemistry and scanning electron microscopy. METHODS: Samples of liposuction-derived human fat were processed for immunohistochemistry and subsequently stained for the presence of von Willebrand factor (vWF), alpha-smooth muscle cell actin, cytokeratin (peptide 18), and the endothelial cell-specific marker EN4. We also performed histochemistry studies on the cells derived from this fat after collagenase dispersion of the liposuction far. RESULTS: Immunohistochemistry revealed that 86.1% of the cells in intact, liposuction-derived fat express vWF, whereas 5.7% of the cells exhibited alpha-smooth muscle cell actin, and 1.0% expressed the mesothelial cell-related antigen, cytokeratin peptide 18. Expression of EN4 was found in 89.6% of the cells counted in intact far. After digestion of fat with collagenase and centrifugal separation of adipocytes from vascular and stromal cells, the expression of vWF, alpha-smooth muscle cell actin, and cytokeratin was 77.5%, 5.8%, and 2.1%, respectively. EN4 expression was observed in 74.6% of the isolated cells. Thus most cells present in liposuction-derived fat, even before tissue digestion and cell isolation, were characterized as endothelium. Although other cells common to mesodermally derived tissue were identified (e.g., adipocytes, smooth muscle cells, and mesothelium), they represented a minor fraction of the total cells present. On isolation, the number of cells expressing vWF- and EN4-specific antigens was less than that observed in intact fat. CONCLUSIONS: This finding suggests that a portion of cells reacting with antibodies in situ lose vWF and EN4 staining during the isolation procedure. Unlike omentum, liposuction-derived fat predominantly contains adipocytes and endothelial cells. On digestion of liposuction-derived fat and separation of cells, vascular endothelial cells represent the major cellular component.

Adipocytes↗

PubMed1994

The inhibitory effect of methotrexate on PAF-induced neutrophil and eosinophil locomotion in asthmatic patients.

We have tested the effect of methotrexate (MTX) on platelet activating factor (PAF)-induced neutrophil and eosinophil locomotion, neutrophil leukotriene B4 (LTB4) generation and mononuclear cell DNA synthesis. Neutrophils from patients treated with low dose methotrexate showed reduced PAF-induced chemotactic responses (727.8 +/- 72.2/10 HPF vs 481.9 +/- 87.3/10 HPF, p < 0.05). Both MTX and the specific PAF antagonist BN-52021 significantly inhibited PAF-induced eosinophil and neutrophil locomotion in a dose-dependent manner. MTX also reduced calcium ionophore-driven LTB4 generation from the neutrophils of asthmatics (358.9 +/- 39.5 pg/10(6) cells vs 240.1 +/- 29.1 pg/10(6) cells, p < 0.05) and attenuated PHA-induced mononuclear DNA synthesis as shown by a reduction in 3H-thymidine uptake and propidium iodide staining. These findings support the view that the beneficial effects of MTX in asthma may be due not only to its anti-mitotic effects on the proliferation of mononuclear cells but also to direct effects on granulocyte locomotion and production of LTB4.

Asthma↗

PubMed1994

The prognostic value of ambulatory blood pressure monitoring in untreated mild-to-moderate hypertensive patients: correlation with echocardiography.

BACKGROUND: Target organ damage by hypertension should be related to the daily duration of blood pressure elevation. METHODS: Thirty-six previously untreated patients with mild to moderate hypertension were examined by 2-D, M-mode, Doppler echocardiography and with 24-hour ambulatory blood pressure monitoring. The resulting parameters were compared with those of normotensive subjects. Elevated BP values during the waking hours (> 125/85 mmHg) and sleeping hours (> 115/80 mmHg) were used to calculate the total percentage of abnormal BP values (load) in each patients. RESULTS: In patients with hypertension, left atrial index and left ventricular mass index were significantly greater than those of normotensive subjects (21 +/- 4 vs 18 +/- 3 mm/m2, p < 0.05; 127 +/- 25 vs 94 +/- 19 gm/m2, p < 0.01). Doppler measurement of diastolic filling velocity was significantly different between the two groups, with an early LV filling velocity lower (38 +/- 11 vs 45 +/- 10 cm/sec, p < 0.05) and a late LV filling velocity higher (50 +/- 9 vs 45 +/- 12 cm/sec, p < 0.05) in the hypertensives. Casual systolic and diastolic BP values did not correlate with cardiac structural and functional variables. There were significantly inverse correlations between both sleeping diastolic blood pressure and sleeping DBP load and fractional shortening (r = -0.39, p < 0.05; r = -0.43, p < 0.01, respectively). CONCLUSIONS: These data showed that the majority of patients with hypertension have either cardiac structural or functional abnormalities, or both. High nocturnal diastolic blood pressure and DBP load may have a more determinant effect on systolic function in mild to moderate hypertensive patients.

Adult↗

PubMed1993

Identification of the peptide binding domain of hsc70. 18-Kilodalton fragment located immediately after ATPase domain is sufficient for high affinity binding.

Recombinant hsc70, a purified glutathione S-transferase (GST) fusion protein containing the C-terminal domain of hsc70 (GST-Ct), and an internal 18-kDa polypeptide located immediately after the 44-kDa ATPase domain of hsc70 were investigated for their peptide binding properties. The dissociation constants of the S-peptide for native hsc70 (Kd = 5-8 microM), GST-Ct (Kd = 6.5 microM), and the 18-kDa fragment (Kd = 8.1 microM) are virtually identical. In addition, polylysine and (Pro-Pro-Gly)5 do not show high affinity toward hsc70, GST-Ct, and the 18-kDa fragment, whereas peptide GT4 and P3a show comparably high affinity toward these polypeptides. These observations indicate that the peptide binding domain of hsc70 is confined in the internal 18-kDa fragment.

Adenosine Triphosphatases↗

PubMed1993

Chronic tonsillitis and IgA nephropathy.

The authors studied the effect of tonsillectomy for IgA nephropathy and the relationship between chronic tonsillitis and IgA nephropathy. Forty-five patients with IgA nephropathy were treated by tonsillectomy in our department. The effective rate of hematuria type IgA nephropathy was 86.2% and that of non-hematuria type 62.5%. We also determined the immunoglobulin composition of the tonsilla tissue in 18 IgA nephropathy patients and compared it with that of 18 chronic tonsillitis patients. The immunoglobin level of the IgA nephropathy group was higher than that of the contrast group, indicating that the disorder of tonsilla immunity may be one of the pathogenic factors for IgA nephropathy. Since no specific method has been available for the treatment of IgA nephropathy, we use tonsillectomy as an effective procedure.

Adolescent↗

PubMed1993

Left atrial appendage smoke-like echo in dilated cardiomyopathy: its clinical significance and relation to left atrial appendage function.

To elucidate the clinical significance and pathogenesis of left atrial appendage smoke-like echo in dilated cardiomyopathy (DCM), clinical history and transesophageal echocardiographic assessment of left atrial appendage (LAA) anatomy and function were studied in 18 DCM patients with smoke-like echo (SE), 34 patients with DCM but no smoke-like echo and in 14 age-matched normal subjects. Patients with SE had a larger left atrial appendage area, a lower peak LAA systolic flow velocity (PLAAV), a greater incidence of atrial fibrillation, with both left atrial appendage thrombi and a history of arterial embolic episodes, than did patients without SE. Patients in sinus rhythm with SE had a minimal LAA area (5.0 +/- 3.0 cm2) larger than that in the no SE group (3.0 +/- 1.6 cm2) (p < 0.05), and LAA ejection fraction (18 +/- 10%) and PLAAV (24 +/- 9 cm/sec) less than that in the no SE group (40 +/- 11% and 39 +/- 16 cm/sec, respectively) (P < 0.05). Patients with atrial fibrillation (AF) and SE had PLAAV (15 +/- 6 cm/sec) less than that in AF patients without SE (30 +/- 12 cm/sec) (p < 0.05). It is concluded that smoke-like echo in LAA is an indicator of DCM patients with an increased thromboembolic risk usually associated with dilated and poorly contractile LAA.

Adult↗

PubMed1993

Duodenal ulcer is a multifactorial disorder--the role of pepsinogen I.

Serum pepsinogen I (PGI) levels were measured in 231 duodenal ulcer (DU) patients and 100 sex- and age-comparable healthy controls. Significantly higher mean serum PGI levels were found in DU patients than in controls (124.7 +/- 3.4 ng/ml v. 92.9 +/- 2.3 ng/ml; P < 0.001) (mean +/- SE). These levels were higher in male DU patients than in female DU patients (128.5 +/- 3.9 ng/ml v. 107.4 +/- 6.4 ng/ml; P < 0.05). Smoking was associated with elevated serum PGI levels in DU patients (145.3 +/- 5.1 ng/ml v. 109.0 +/- 4.2 ng/ml; P < 0.001). Healed DUs were associated with lower mean serum PGI levels than active ulcers (110.9 +/- 7.6 ng/ml v. 129.4 +/- 3.8 ng/ml, P < 0.05). Whether patients were positive or negative for Helicobacter pylori, infection did not affect mean serum PGI levels. All the risk factors for DU may not affect serum PGI levels and DU may therefore be considered a multifactorial disease.

Duodenal Ulcer↗

PubMed1993

[Kimura's disease: a case report].

Kimura's disease is endemic in Orientals. The pathogenesis of Kimura's disease is currently unknown, and the methods of treatment are undefined. The patient was a 21-year-old male, suffering from neck mass left over the parotid region of which the mass gradually increased and which combined with lymphadenopathy and pruritus over both lower limbs more than two years. The patient was diagnosed with Kimura's disease by neck lymph node biopsy, then received simple excision of mass and oral prednisolone therapy. The symptoms of lymphadenopathy and pruritus were improved without recurrence of neck mass.

Adult↗

PubMed1992

Serum pepsinogen I levels of gastric ulcer patients are determined by the location of the ulcer crater.

To examine the relation between gastric ulcer (GU) location and serum pepsinogen I (PGI) level, we measured this marker in 284 endoscopically proved GU patients. Their ulcer locations were further divided according to Johnson's criteria modified to the corpus (type 1a), gastric angle (type 1b), combined with duodenal ulcer (type 2) and prepyloric area (type 3). The number of each subset were 96, 81, 58 and 49, respectively. Mean serum PGI level (99.6 +/- 44.8 ng/ml) of all GU patients showed no difference from that of their sex and age matched controls. Mean serum PGI levels in both type 1a and 1b patients, did not differ from each other but were significantly lower than in controls, in contrast to those in type 2 and 3 patients which were significantly higher than in controls and comparable to the PGI levels of patients with duodenal ulcer. Smoking did not affect mean serum PGI levels in all subsets except the smoking type 2 patients who manifested a significantly higher mean PGI level. Helicobacter pylori infection did not show different serum PGI levels in any subset. In conclusion, different location of ulcer in the stomach results in a characteristic serum PGI level.

Duodenal Ulcer↗

PubMed1992

Relationship of portal pressure, anorectal varices and hemorrhoids in cirrhotic patients.

In a prospective study of 103 consecutive cirrhotic patients a high prevalence (43%) of anorectal varices was found compared with only 2% in 103 age- and sex-matched control subjects (p less than 0.001). However, there was no significant difference between the prevalences of hemorrhoids in cirrhotic patients and in control subjects (79% vs. 83%, p greater than 0.05). The hepatic venous pressure gradient of cirrhotic patients with anorectal varices was similar to cirrhotic patients without anorectal varices (14 +/- 6 mmHg, n = 22, vs. 16 +/- 7 mmHg, n = 39, p greater than 0.05. There was no significant difference in the hepatic venous pressure gradient between cirrhotic patients with and without hemorrhoids (15 +/- 6 mmHg, n = 47, vs. 16 +/- 8 mmHg, n = 14, p greater than 0.05). The prevalence of anorectal varices and hemorrhoids in cirrhotic patients had no relation to Child-Pugh's grading, esophageal varices with and without sclerotherapy and ascites. We conclude that anorectal varices are common in cirrhotic patients. Anorectal varices and hemorrhoids are not related to the degree of portal pressure.

Aged↗

PubMed1992

Location and type of gastric carcinoma in relation to pepsinogen I level in blood.

Serum pepsinogen I (PGI) levels were measured in 192 gastric carcinoma (GC) patients and 70 controls. Among GC patients serum PGI levels were not influenced by the following variables: age, sex, smoking, Borrmann's or Lauren's classification, tumor size, cellular differentiation, and layer of invasion. The mean serum PGI levels of tumors restricted to the body, antrum, or involving both areas were 64.8 +/- 37.6 ng/ml, 76.0 +/- 47.0 ng/ml, and 51.1 +/- 25.5 ng/ml, respectively (P < 0.005). Odds ratios of GC patients from the quartile of 262 serum PGI levels in the limits > or = 100 ng/ml, 70-99.9 ng/ml, 45-69.9 ng/ml, and < 45 ng/ml were 1.00, 0.76, 3.44, and 37.1, respectively (P < 0.001). The lower serum PGI levels of Chinese GC patients seem to be related to disease location rather than other characters of the tumor.

Adult↗

PubMed1991

In vivo dissociation kinetics of [3H]quinuclidinyl benzilate: relationship to muscarinic receptor concentration and in vitro kinetics.

The in vivo washout kinetics of [3H]quinuclidinyl benzilate ([3H]QNB) varies significantly in various structures in the rat brain. The slowest washout rates are from the hippocampus, corpus striatum, and cortex, intermediate rates are exhibited from the thalamus and colliculi, while the fastest washout rate is from the cerebellum. We have also demonstrated a difference in the in vitro dissociation rates (k-1) of [3H]QNB from various structures. The k-1 for the hippocampus, corpus striatum and cortex, is two-fold slower than that observed in the thalamus, colliculi, and cerebellum. The differences in the in vitro dissociation kinetics are not, however, sufficient to explain the differences in the in vivo washout kinetics. We have developed a theoretical formulation which describes conditions under which the washout kinetics are a function of the concentration of receptor in a structure. Furthermore, we present a graphical method in which a plot of the reciprocal of the observed washout rate constant, 1/k(obs), vs receptor concentration is linear. Analysis of the washout kinetics of [3H]QNB from various structures of the CNS of rat were well described by this theory when the differences in in vitro k-1 are included.

Animals↗