Neutrophil inhibition contributes to cardioprotection by postconditioning.

BACKGROUND: Postconditioning (postcon) reduces infarct size, myocardial superoxide ((•)O(2)) generation, and neutrophil (PMN) accumulation. It is unknown whether inhibition of PMNs influence cardioprotection by postcon. The present study tested the following hypotheses: (1) myocardial salvage by postcon is modified by inhibition of PMNs and (2) postcon directly inhibits PMN (•)O(2) generation. METHODS: For hypothesis 1, a deductive approach was used to determine infarct size in vivo with and without PMNs in rats, and for hypothesis 2, blood sampled from the anterior interventricular vein (AIV) in a canine model was used. Protocol 1: anesthetized rats, subjected to 30 min of coronary artery occlusion and 3 h of reperfusion, were randomized to control (n = 13), postcon (n = 13), PMN-depletion: (n = 9), and postcon in PMN-depleted rats (n = 9). Protocol 2: blood was sampled at baseline, 2 h and 24 h from the AIV, draining the area at risk (AAR) in anesthetized dogs with 60 min coronary occlusion ± postcon; whole blood was analyzed for (•)O(2) by luminol-enhanced chemiluminescence. RESULTS: Postcon and PMN depletion reduced infarct size (42.6 ± 2.1%, P < 0.05 vs. control, and 43.9 ± 3.0%, P < 0.05 vs. control, respectively) vs. control (58.8 ± 0.9%), with no further decrease with postcon in PMN-depleted rats (37.2 ± 2.9%, P = 0.34 vs. postcon). PMN accumulation in AAR was less in postcon (21.2 ± 0.3%, P < 0.05 vs. control) and PMN-depleted (9.4 ± 0.3%, P < 0.05 vs. control) vs. control (30.5 ± 1.2%), with a further decrease in the postcon + PMN depletion group (5.4 ± 0.6%, P < 0.05 vs. control). In dogs, (•)O(2) release by PMNs increased at 2 h and 24 h of R, which was reduced to baseline levels by postcon. CONCLUSIONS: These data imply PMN involvement in cardioprotection by postconditioning.

Agonists at PPAR-gamma suppress angiotensin II-induced production of plasminogen activator inhibitor-1 and extracellular matrix in rat cardiac fibroblasts.

BACKGROUND AND PURPOSE: Peroxisome proliferator-activated receptor (PPAR)-gamma ligands have been shown to inhibit cardiac fibrosis. However, the underlying mechanisms are poorly understood. We investigated the regulation by PPAR-gamma ligands of angiotensin (Ang) II-induced plasminogen activator inhibitor (PAI)-1, extracellular matrix (ECM) production and cell growth in cardiac fibroblasts. EXPERIMENTAL APPROACH: The effects of PPAR-gamma ligands on Ang II-induced PAI-1, ECM expression and cell growth were assessed in primary-cultured rat cardiac fibroblasts; cardiac PAI-1 and ECM production was examined in Ang II-infused rats. KEY RESULTS: In growth-arrested cardiac fibroblasts, PPAR-gamma ligands rosiglitazone and 15-deoxy-Delta(12,14)-prostaglandin J2 (15d-PGJ2) dose-dependently attenuated Ang II-induced cell proliferation and expression of PAI-1, collagen type-I, collagen type-III and fibronectin. An accompanying increase in PPAR-gamma expression and activation was also observed. These suppressive effects were attenuated by the PPAR-gamma antagonists GW9662 and bisphenol A diglycidyl ether (BADGE). Moreover, rosiglitazone and 15d-PGJ2 inhibited in part the expression and phosphorylation of Ang II-induced transforming growth factor (TGF)-beta1, Smad2/3 and c-Jun NH(2)-terminal kinase (JNK). Ang II infusion in rats markedly increased left ventricular production of PAI-1, collagen and fibronectin, with a concurrent increase in the ratios of heart weight/body weight and left ventricle weight/body weight. Co-treatment with rosiglitazone significantly decreased these levels and upregulated PPAR-gamma expression. CONCLUSIONS AND IMPLICATIONS: Rosiglitazone and 15d-PGJ2 suppress Ang II-induced production of PAI-1 and ECM probably via interactions between PPAR-gamma and TGF-beta1/Smad2/3 and JNK signalling pathways. It is suggested that PPAR-gamma and its ligands may have potential applications in preventing cardiac fibrosis.

Tumor suppressor activity of RB and p53 genes in human breast carcinoma cells.

Breast cancer is the most common cancer of women in Western countries. Various genetic alterations have been implicated in its development. Two tumor suppressor genes, the retinoblastoma susceptibility gene (RB) and the gene encoding the p53 protein, are frequently found to be deleted or mutated in breast cancer cell lines and primary tumor samples. Breast carcinoma cell lines MDA-MB468 and BT549 both harbor partial RB gene deletions as well as point mutations of their p53 genes, thus providing an excellent model system for testing the roles played by these two genes in the oncogenesis of breast cancer. Single copies of wild-type RB or p53 were delivered to these cells by retrovirus-mediated gene transfer. Restoration of RB expression in cells reduced their ability to grow in soft agar and their tumorigenicity in nude mice, although no significant alteration of growth rate in culture could be detected. Introduction of wild-type p53 into these cells exerted a similar effect on the neoplastic phenotypes. This effect occurred even in the presence of their endogenous mutated p53 alleles, which argues for the phenotypical dominance of the wild-type p53 over mutated p53 during human oncogenesis. The ability of RB and p53 genes to suppress the tumorigenicity of breast carcinoma cells provides functional evidence that deletion or mutational inactivation of tumor suppressor genes represents an important step in the genesis of breast cancer.

Cholesterol enrichment upregulates intercellular adhesion molecule-1 in human vascular endothelial cells.

Hypercholesterolemia is a major risk factor for atherosclerosis, but the mechanism by which cholesterol activates the endothelium remains undocumented. The present investigation was undertaken to investigate the role of cholesterol, one of the bioactive moieties of the low-density lipoprotein (LDL) particle, in initiating of intracellular signaling in endothelial cells (ECs) and culminating in increased abundance of the intercellular adhesion molecule-1 (ICAM-1). Cholesterol was delivered to human umbilical vein ECs (HUVECs) via cholesterol-enriched liposomes. In HUVECs, the cellular cholesterol:phospholipid ratio increased after 1 h of exposure to cholesterol. The level of ICAM-1 increased in both mRNA and protein after 24 h of cholesterol exposure. ICAM-1 mRNA half-life was not affected by cholesterol exposure. Promoter studies showed greater than two-fold activation of the ICAM-1 gene expression after cholesterol exposure. Electrophoretic mobility shift assay showed that activator protein-1 (AP-1) activity substantially increased after 2 h of exposure to cholesterol. In contrast, cholesterol did not affect nuclear factor-kappaB (NF-kappaB) activity. Results of trans-reporting assay revealed 2.5-fold increased expression of the AP-1-dependent reporter gene after cholesterol exposure whereas NF-kappaB-dependent expression was not affected. The AP-1/Ets (-891 to -908) site, one of the three AP-1-like sites in the ICAM-1 promoter, was most responsive to cholesterol. These data demonstrate for the first time that cholesterol enrichment phenotypically modulates ECs by transcriptionally upregulating ICAM-1 expression.

Glutathione reverses endothelial damage from peroxynitrite, the byproduct of nitric oxide degradation, in crystalloid cardioplegia.

BACKGROUND: NO has been advocated as an adjunct to cardioplegia solutions. However, NO undergoes a rapid biradical reaction with superoxide anions to produce peroxynitrite (ONOO(-)). ONOO(-) in crystalloid cardioplegia solution induces injury to coronary endothelium and to systolic function after cardioplegia and reperfusion. However, ONOO(-) may be degraded to less lethal or cardioprotective intermediates with glutathione (GSH) in reactions separate from its well known antioxidant effects. We hypothesized that GSH detoxifies ONOO(-) and reverses defects in endothelial function and systolic function when present in crystalloid cardioplegia. METHODS AND RESULTS: In anesthetized dogs on cardiopulmonary bypass, a 45-minute period of global normothermic ischemia was followed by 60 minutes of intermittent cold crystalloid cardioplegia (Plegisol) and 2 hours of reperfusion. The cardioplegia solution contained 5 micromol/L authentic ONOO(-); catalase was included to attenuate the potential antioxidant effects of GSH and to unmask the effects on ONOO(-). In 1 group (CP+GSH, n=5), the cardioplegia contained 500 micromol/L GSH, whereas 1 group received crystalloid cardioplegia without GSH (CCP, n=6). There were no group differences in postcardioplegia left ventricular systolic function (end-systolic pressure-volume relation, impedance catheter: CCP 10.0+/-2.4 versus CP+GSH 10.6+/-1.3 mm Hg/mL) or diastolic chamber stiffness (ss-coefficient: CCP 0.35+/-0.2 versus CP+GSH 0.31+/-0.18). Myocardial neutrophil accumulation (myeloperoxidase activity) was attenuated in CP+GSH versus CCP (2.2+/-0.7 versus 5.4+/-1.2, P:<0.05). In postexperimental coronary arteries, maximal endothelium-dependent relaxation was greater in CP+GSH than in CCP (118+/-6% versus 92+/-5%, P:<0.05), with a smaller EC(50) value (-7. 10+/-0.05 versus -6.98+/-0.03, respectively, P:<0.05). Smooth muscle relaxation was complete in both groups. The adherence of neutrophils to postexperimental coronary arteries as a measure of endothelial function was less in CP+GSH than in CCP (98+/-18 versus 234+/-36 neutrophils/mm(2), P:<0.05). Nitrosoglutathione, a byproduct of the reaction between ONOO(-) and GSH, was greater in CP+GSH than in CCP (4.1+/-2.3 versus 0.4+/-0.2 microg/mL, P:<0.05). CONCLUSIONS: GSH in crystalloid cardioplegia detoxifies ONOO(-) and forms cardioprotective nitrosoglutathione, resulting in attenuated neutrophil adherence and selective endothelial protection through the inhibition of neutrophil-mediated damage.

Reperfusion induces myocardial apoptotic cell death.

OBJECTIVE: The purpose of the present study was to investigate whether apoptosis is triggered during ischemia (I) and reperfusion (R) and whether I/R-induced apoptosis is correlated with changes in expression of Bcl-2 and Bax. METHODS: Anesthetized open-chest dogs were divided into two groups. Group I: 7 h of permanent I without R (PI, n = 7); Group II: 60 min I followed by 6 h R (I/R, n = 8). Apoptosis was identified as "DNA ladder" by agarose gel electrophoresis or confirmed histologically using the terminal transferase UTP nick end labeling (TUNEL) assay. RESULTS: Collateral myocardial coronary blood flow during I, confirmed by colored microspheres was comparable in both groups. Although PI caused 72 +/- 5% infarct size, very few TUNEL-positive cells were detected in the necrotic area (0.2 +/- 0.1% of total normal nuclei), consistent with an absence of DNA laddering. In contrast, the appearance of TUNEL-positive cells was significantly displayed after 6 h R in the necrotic area in I/R group (26 +/- 4%, P < 0.001 vs. PI group), and DNA ladder occurred in all experimental animals, suggesting that myocardial apoptosis is primarily elicited by R. Densitometrically, Western blot analysis showed significant reduction in expression of Bcl-2 (16 +/- 1%) and increase in Bax (29 +/- 8%) after 6 h R in the necrotic area compared with normal tissue while expression of these two proteins was not changed in the PI group. Polymorphonuclear neutrophil (PMN) accumulation in the necrotic area determined either by immunohistochemistry with anti-CD18 antibody or by myeloperoxidase activity was significantly increased in the I/R group compared to the PI group (358 +/- 24 vs. 24 +/- 2, mm2 myocardium, P < 0.01) and (2.9 +/- 0.3 vs. 0.4 +/- 0.1, U/100 mg tissue, P < 0.01). There was a significant linear relationship between CD18-positive PMNs and TUNEL-positive cells (P < 0.05) in the I/R group. CONCLUSIONS: These results indicate that (1) PI without R did not induce apoptotic cell death, while two types of cell death, necrosis and apoptosis were found after I/R, (2) the Bcl-2 family may participate in early R-induced myocardial apoptosis, (3) PMN accumulation may play a role in the development of apoptosis.

Preconditioning decreases Bax expression, PMN accumulation and apoptosis in reperfused rat heart.

OBJECTIVE: Recent studies suggest that ischemic preconditioning (IPC) inhibits myocardial apoptosis after ischemia and reperfusion. This study tested the hypothesis that IPC reduces ischemia/reperfusion-induced myocardial apoptosis by inhibiting neutrophil (PMN) accumulation and altering expression of Bcl-2 and Bax proteins. METHODS: Eighteen rats were subjected to 30 min of left coronary artery occlusion followed by 180 min of reperfusion with IPC (5 min ischemia and 10 min of reperfusion, n = 10) or without IPC (n = 8). Myocardial apoptosis was detected histologically using the terminal transferase UTP nick end labeling (TUNEL) assay and confirmed by DNA ladder on agarose gel electrophoresis. PMN accumulation was detected immunohistochemically with anti-rat CD18 antibody (WT3) and expression of Bcl-2 and Bax proteins was analyzed using Western blot assay. RESULTS: IPC significantly decreased TUNEL positive cells (% total nuclei) in the ischemic zone from 28.6 +/- 2.8 to 3.4 +/- 0.9 (P < 0.05), consistent with the absence of DNA ladders in the IPC group. IPC significantly attenuated PMN accumulation (cells/mm2 myocardium) in the ischemic zone from 243 +/- 19 to 118 +/- 19 (P < 0.05). By regression analysis, there was a significant correlation between TUNEL positive cells and accumulated CD18 positive PMNs in the ischemic zone (r = 0.8, P < 0.001), which was shifted downward by IPC. Densitometrically, IPC significantly attenuated the ischemia/reperfusion-upregulated expression of Bax protein in the ischemic zone from 204 +/- 57% in the control group to 76 +/- 7% (P < 0.05), while the expression of Bcl-2 was not different from the non-ischemic zone in either group. CONCLUSION: These data suggest that ischemic preconditioning may reduce myocardial apoptosis by inhibiting PMN accumulation and down-regulating expression of Bax.

Purification and characterization of [3H]mepyramine (histamine H1 antagonist)-binding protein from rat liver: a highly homologous protein with cytochrome P450 2D.

A protein having a high-affinity binding site for [3H]mepyramine (MBP) was purified to homogeneity from rat liver membranes. The purified MBP has a single type of binding site for [3H]mepyramine with Kd value of 18.5 nM, and its molecular weight was determined to be 56,000 by SDS polyacrylamide gel electrophoresis. Amino acid sequences of twelve tryptic peptides derived from MBP are highly homologous with those of rat debrisoquine 4-hydroxylase (cytochrome P450 2D1) and other rat P450 2D subfamily members. In immunoblotting analysis, an antibody against rat P450 2D1 stained a band corresponding to MBP with Mr of 56,000; its migration position was clearly different from that of rat P450 2D1. Substrates and inhibitors of debrisoquine 4-hydroxylase potently displace [3H]-mepyramine binding to MBP. Quinine and quinidine showed 400 and 80 times, respectively, higher affinity for MBP than for debrisoquine 4-hydroxylase. These results suggest that MBP is a novel P450 2D family member.

Ischemic preconditioning reduces neutrophil accumulation and myocardial apoptosis.

BACKGROUND: This study tested the hypothesis that ischemic preconditioning (IP) inhibits myocardial apoptosis after a short period of ischemia and reperfusion. METHODS: In 9 anesthetized dogs, the left anterior descending (LAD) coronary artery was occluded for 30 min and reperfused for 3 h (control), while in 9 others, LAD occlusion was preceded by 5 min of occlusion and 5 min of reperfusion (IP). DNA from frozen myocardial tissue samples was extracted, and apoptosis were identified as "ladders" by agarose gel electrophoresis or confirmed histologically using the terminal transferase UTP nick end-labeling (TUNEL) assay. Neutrophil accumulation was detected by measuring cardiac myeloperoxidase activity. RESULTS: Thirty minutes of LAD occlusion caused a significant decrease in blood flow (colored microspheres), which was comparable between groups. In the control group, DNA ladders occurred in the area at risk (AAR) in six out nine experiments. In contrast, DNA laddering in the AAR was not observed in any of the IP group. AAR in the control group showed a greater percentage of apoptotic cells than IP (6.7 +/- 0.9% vs 1.2 +/- 0.2%; p < 0.01). Cardiac myeloperoxidase activity (U/g tissue) was significantly reduced from 0.07 +/- 0.004 in control to 0.04 +/- 0.01 in IP group (p < 0.05). CONCLUSIONS: We conclude that ischemic preconditioning attenuates apoptosis and neutrophil accumulation in the AAR in a model of nonlethal acute ischemia and reperfusion.

Hypothermic circulatory arrest causes multisystem vascular endothelial dysfunction and apoptosis.

BACKGROUND: Multiple organ failure after deep hypothermic circulatory arrest (DHCA) may occur secondary to endothelial dysfunction and apoptosis. We sought to determine if DHCA causes endothelial dysfunction and apoptosis in brain, kidney, lungs, and other tissues. METHODS: Anesthetized pigs on cardiopulmonary bypass were: (1) cooled to 18 degrees C, and had their circulation arrested (60 minutes) and reperfused at 37 degrees C for 90 minutes (DHCA, n = 8); or (2) time-matched normothermic controls on bypass (CPB, n = 6). Endothelial function in cerebral, pulmonary, and renal vessels was assessed by vasorelaxation responses to endothelial-specific bradykinin (BK) or acetylcholine (ACh), and smooth muscle-specific nitroprusside. RESULTS: In vivo transcranial vasorelaxation responses to ACh were similar between the two groups. In small-caliber cerebral arteries, endothelial relaxation (BK) was impaired in CPB vs DHCA (maximal 55% +/- 2% [p < 0.05] vs 100% +/- 6%). Pulmonary artery ACh responses were comparable between CPB (110% +/- 10%) and DHCA (83% +/- 6%), but responses in pulmonary vein were impaired in DHCA (109% +/- 3%, p < 0.05) relative to CPB (137% +/- 6%). In renal arteries, endothelial (ACh) responses were impaired in DHCA (71% +/- 13%) relative to CPB (129% +/- 14%). Apoptosis (DNA laddering) occurred primarily in duodenal tissue, with a greater frequency in DHCA (56%, p < 0.05) compared with normothermic CPB (17%) and nonbypass controls (0%). CONCLUSIONS: DHCA is associated with endothelial dysfunction in cerebral microvessels but not in the in vivo transcranial vasculature; in addition, endothelial dysfunction was noted in large-caliber renal arteries and pulmonary veins. DHCA is also associated with duodenal apoptosis. Vascular endothelial dysfunction and apoptosis may be involved in the pathophysiology of multisystem organ failure after DHCA.

Characterization of histamine H1-receptors on astrocytes in primary culture: [3H]mepyramine binding studies.

The characteristics of histamine H1-receptors on astrocytes from the cerebral cortex of newborn rats in primary culture were analyzed with a [3H]mepyramine binding assay, and compared with those in the cerebral cortex. The apparent dissociation constant (KD) of [3H]mepyramine binding, the apparent inhibition constants (Ki) of various H1-ligands for [3H]mepyramine binding and the stereoselectivity of d- and l-chlorpheniramine for the inhibition of [3H]mepyramine binding to receptors on cultured astrocytes and to receptors in the brain tissue were very similar, indicating that these receptors are identical. The apparent density of H1-receptors (Bmax) on astrocytes was 262 +/- 60 fmol/mg protein, which was comparable to that in the brain tissue (194 +/- 24 fmol/mg protein). The development of H1-receptors on cultured astrocytes resembled the postnatal development of the receptors in the rat brain. These results suggest that astrocytes could be one of the main targets of the central histaminergic system.

Administration of adenosine during reperfusion reduces injury of vascular endothelium and death of myocytes.

INTRODUCTION: To test the hypothesis that administration of adenosine during reperfusion attenuates endothelial dysfunction and extension of infarct size by inhibiting polymorphonuclear neutrophil (PMN)-mediated events and apoptosis. METHODS: Anesthetized dogs were subjected to 1 h coronary artery occlusion and 6 h of reperfusion with infusion of saline (vehicle, n = 8) or 140 micrograms/kg per min adenosine, n = 8) continuously into the left atrium starting 5 min before reperfusion and continuing for 2 h. RESULTS: There was no intergroup difference in collateral myocardial blood flow measured by using colored microspheres in the area at risk during ischemia. Infusion of adenosine transiently improved segmental shortening (4.1 +/- 3.1% versus -2.5 +/- 2.3%, P < 0.05) and segmental work (41.4 +/- 22 versus 15 +/- 13 mmHg/mm, P < 0.05) after 4 h of reperfusion. Infusion of adenosine reduced size of infarct (determined by staining with triphenyltetrazolium chloride) from 27 +/- 2% with vehicle to 14 +/- 1%, (P < 0.05). This was confirmed by measuring that it lowered activity of plasma creatine kinase (from 19 +/- 2 versus 8 +/- 1 IU/g protein, P < 0.05). It also reduced the proportion of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive nuclei in the perinecrotic zone from 17.3 +/- 1.6 to 10.3 +/- 1.0% (P < 0.05) and reduced the appearance of DNA ladders in gel electrophoresis. In addition, it significantly decreased accumulation of PMN in the ischemic area (determined by immunohistochemistry with anti-CD18 antibody) and activity of cardiac myeloperoxidase compared with vehicle (439 +/- 52 versus 183 +/- 20 PMN/mm2 myocardium and 1.1 +/- 0.1 versus 2.4 +/- 0.2 U/100 mg tissue, P < 0.05, respectively). Furthermore, infusion of adenosine during reperfusion preserved vascular endothelial function expressed in terms of a decrease in adherence of PMN to postischemic coronary artery endothelium (63 +/- 3 versus 36 +/- 4 PMN/mm2 endothelium, P < 0.05, basal function) and agonist (acetylcholine)-induced endothelium-dependent relaxation (negative logarithm to base 10 of concentration (mol/l) for half-maximal effect 7.7 +/- 0.1 versus 7.2 +/- 0.1, P < 0.05, stimulated function). Infusion of adenosine directly inhibited generation of superoxide radical from canine PMN in vitro dose dependently from 27.8 +/- 6.3 to 5.8 +/- 2.1 nmol/l/5 x 10(6) PMN (P < 0.05). CONCLUSION: Intra-atrial infusion of adenosine during reperfusion reduced accumulation of PMN in area at risk, preserved vascular endothelial function after ischemia-reperfusion by inhibiting interaction between PMN and endothelial cells, and decreased extension of infarct, possibly by limiting apoptosis.

[3H]mepyramine binding sites, histamine H1-receptors, in bovine retinal blood vessels.

The presence of histamine H1-receptors in the bovine retinal blood vessels was studied with a [3H]mepyramine binding assay. The membranes of purified vessels obtained from bovine retinas showed specific [3H]mepyramine binding sites with a dissociation constant (KD) of 2.78 +/- 0.32 nM. This was similar to values obtained from the retinal neuronal fractions. The binding capacity (Bmax) was 53.8 +/- 1.7 fmol/mg protein, which was about a half that of the retinal neuronal fractions (108.9 +/- 3.1 fmol/mg protein). Some H1-antagonists proved to be potent competitors for [3H]mepyramine binding sites in bovine retinal blood vessels. These results indicate that histamine H1-receptors exist in the retinal blood vessels which may be involved in the physiological and the pathological responses of blood circulation in retinas.

Comparison of particulate mass, chemical species for urban, suburban and rural areas in central Taiwan, Taichung.

Aerosol samples for PM2.5, PM(2.5-10) and TSP were collected from June to September 1998 and from February to March 1999 in central Taiwan. Ion chromatography was used to analyze the acidic anions: sulfate, nitrate and chloride in the Universal samples. The ratios of fine particle concentrations to coarse particle concentrations displayed that the fine particle concentrations are almost greater than that of coarse particle concentrations in Taichung area. The average concentrations of PM2.5, PM(2.5-10) and TSP in urban sites are higher than in suburban and rural sites at both daytime and night-time. Chloride dominated in the coarse mode in daytime and in fine mode in night-time. Nitrate can be found in both the coarse and fine modes. Sulfate dominated in fine mode in both daytime and night-time.

The study of TSP, PM(2.5-10) and PM2.5 during Taiwan Chi-Chi Earthquake in the traffic site of central Taiwan, Taichung.

Ambient particle concentration was taken on the traffic sampling site over the Chung-Chi Road over bridge (CCROB) in front of Hungkuang Institute of Technology (HKIT). The sampling time was from August 1999 to December 1999. During the sampling period, Taiwan's biggest earthquake in more than a century registered 7.3 on the Richter scale (Taiwan Chi-Chi Earthquake). Besides, there were more than 20,000 aftershocks that followed the Taiwan Chi-Chi Earthquake within three months. Thus, the PM2.5, PM(2.5-10) particle concentrations were also collected then and compared with total suspended particle (TSP) in this study. The average PM(2.5-10), PM2.5 and TSP concentrations are 24.6, 58.0 and 106 microg/m3, respectively, after the Taiwan Chi-Chi Earthquake. The average TSP concentrations before and after Taiwan Chi-Chi Earthquake were 70 and 127 microg/m3, respectively. It is clearly shown that the average concentration of TSP after Taiwan Chi-Chi Earthquake was about 1.8 times as that of TSP concentration before Taiwan Chi-Chi Earthquake in the traffic site of central Taiwan. And the ratios of PM2.5/PM(2.5-10), PM2.5/PM10 and PM2.5/TSP are 2.2%, 67.2%, 38.9%, respectively. The results also indicated about Chi-Chi fine particle concentration (PM25) and the TSP increases in the traffic site of central Taiwan after Taiwan Chi-Chi Earthquake.

Video-assisted thoracoscopic T2 sympathetic block by clipping for palmar hyperhidrosis: analysis of 52 cases.

BACKGROUND: Endoscopic thoracic sympathectomy or sympathicotomy is a standard method in treating palmar hyperhidrosis, but postoperative compensatory sweating may be troublesome in some patients. Therefore, we designed a new technique for only T2 sympathetic blocking by clipping instead of interruption of the sympathetic trunk. PATIENTS AND METHODS: Between September 2000 and July 2001, we saw a total of 100 patients with palmar hyperhidrosis who underwent video-assisted thoracoscopic sympathetic blocking of the T2 ganglion. All patients were placed in a semisitting position under single-lumen intubated anesthesia. We performed sympathetic blocking by clipping of the T2 ganglion at the level of the second and third rib beds using an 8-mm, 0 degree thoracoscope (Storz). RESULTS: We supposed that the postoperative improvement in palmar hyperhidrosis would be perfect. The operation could be accomplished within 30 minutes. All patients were discharged within 4 hours after the operation. Surgical complications were minimal, without surgical mortality. A few patients were willing to receive the reverse operation and should get improvement of compensatory sweating after removal of the endo clips. CONCLUSION: We believe that video-assisted thoracoscopic T2 sympathetic block by clipping will be a safe and effective method of treating patients with palmar hyperhidrosis. Compensatory sweating may be improved by the reverse operation: removal of the endo clip.

Determination of age-related changes of cytochrome P-450 sensitive to mepyramine in rat hepatic microsomes.

The cytochrome P-450 (Cyt P-450) sensitive to mepyramine (HP-450) in liver microsome is a protein that possesses properties of both H1 receptor and cytochrome P-450. We used [3H]mepyramine radioligand binding assay and enzymological technique to study the kinetic properties of HP-450 and Cyt P-450. Age-related changes in the Bmax, Kd of HP-450 and Cyt P-450 in rat hepatic microsome were demonstrated. The levels of Bmax for both HP-450 and the Cyt P-450 dramatically increased in the postnatal period from the second to the eighth week, and reached maximum steady status during the eighth to tenth week. The values of Bmax of HP-450 correlated well with the content of Cyt P-450 in rat liver microsome (r = 0.625). The affinity of HP-450 (Kd) decreased with the growth of rats during postnatal. No sexual-related difference was observed in this experiment.

[Preliminary evaluation of inoculation of hepatitis B vaccine in normal adult subjects].

A total of 107 subjects in population without HBsAg, anti-HBs and anti-HBc were inoculated with hepatitis B vaccine in month 0, 1, 6, respectively and followed up for three years. Seven months after the administration of first dose of vaccine response rate of anti-HBs was 94.4%, of which 68.2% had a S/N ratio greater than 10. Three years later the response rate of anti-HBs dropped to 75.7% and the rate of S/N ratio 10 fell to 46.7%, 20 subjects turned negative for anti-HBs and one turned positive for HBsAg. During the same period, of 124 adults who were hepatitis B virus markers negative and were not inoculated, 14 became HBsAg-positive (ALT increased in 3 of them) and 3 turned anti-HBs positive.

[Experimental studies of antitumor effect of artesunate on liver cancer].

OBJECTIVE: To observe the inhibiting effect of Artesunate on liver cancer in vitro and in vivo. METHOD: The mice bearing H22 solid and ascitic liver tumor were applied in vivo experiments. Microculture tetrazolium assay and colony-forming unit assay were applied to test the cytotoxicity to human hepatocarcinoma SMMC-7721 cell line in vitro. RESULT: The growth of solid tumor were obviously inhibited by Artesunate at the dose of 300 mg.kg-1.d-1 ig for 7 days. The tumor inhibiting rates of Artesunate were 49.1%, 48.7%, 46.6% in 3 experiments respectively. After administration of Artesunate, the survival rate of the mice bearing H22 ascitic liver tumor were increased to 45%. Compared with the control groups, the difference was statistically significant (P < 0.01). In additional, Artesunate can synergize the antitumor activity of 5-fluorouracil. Artesunate showed evident cytotoxicity to human hepatocarcinoma SMMC-7721 cells, the IC50 of Artesunate being 2.07 micrograms.ml-1 in MTT experiment and 2.48 micrograms.ml-1 in colony-forming unit experiment. CONCLUSION: Artesunate has marked antitumor activity in vitro and in vivo.