Decreased expression of phospholipase C-beta 2 isozyme in human platelets with impaired function

Platelets from a patient with a mild inherited bleeding disorder and abnormal platelet aggregation and secretion show reduced generation of inositol 1,4,5-trisphosphate, mobilization of intracellular Ca2+, and phosphorylation of pleckstrin in response to several G protein mediated agonists, suggesting a possible defect at the level of phospholipase C (PLC) activation (see accompanying report). A procedure was developed that allows quantitation of platelet PLC isozymes. After fractionation of platelet extracts by high-performance liquid chromatography, 7 out of 10 known PLC isoforms were detected by immunoblot analysis. The amount of these isoforms in normal platelets decreased in the order PLC- gamma 2 > PLC-beta 2 > PLC-beta 3 > PLC-beta 1 > PLC-gamma 1 > PLC- delta 1 > PLC-beta 4. Compared with normal platelets, platelets from the patient contained approximately one-third the amount of PLC-beta 2, whereas PLC-beta 4 was increased threefold. These results suggest that the impaired platelet function in the patient in response to multiple G protein mediated agonists is attributable to a deficiency of PLC-beta 2. They document for the first time a specific PLC isozyme deficiency in human platelets and provide an unique opportunity to understand the role of different PLC isozymes in normal platelet function.     

Possible effect of secretor locus on plasma concentration of factor VIII and von Willebrand factor

A significant fraction (30%) of the genetically determined variance in plasma concentration of the von Willebrand factor antigen (vWf:Ag) has been shown to be related to ABH determinants. Individuals with blood group O, who have the highest amounts of blood group H substance, have the lowest concentration of vWf:Ag. The Lewis substances, Le(a) and Le(b), are biochemically closely related to the ABH substances as both can be produced from the same precursor substance. We studied the effect of the presence of the Lewis antigens on the plasma concentration of vWf:Ag and factor VIII antigen (VIII:Ag) in 323 individuals of different ABO groups from a series of twins and in 58 blood donors of blood group O. Among persons belonging to blood group O, those with the Le(a) antigen had a higher concentration of both vWf:Ag and VIII:Ag than individuals lacking Le(a). Le(a+b-) people are nonsecretors and Le(a-b+) people are secretors of ABH substance. Thus, the lowest concentration of vWf:Ag and VIII:Ag was found in group O secretors. The effect is most likely due to an effect of the secretor locus. This finding may be of importance for the detection of carriers of hemophilia A and for the diagnosis of type I von Willebrand disease.     

Clinical safety of drug-eluting stents in the Korea acute myocardial infarction registry.

BACKGROUND: Percutaneous coronary intervention (PCI) with drug-eluting stents (DES) may be useful in patients with acute myocardial infarction (AMI), but safety issues still need to be solved. This study was undertaken to investigate the incidence of major adverse cardiac events (MACE) and stent thrombosis in DES-implanted AMI patients in real-life clinical practice. METHODS AND RESULTS: On-line registry of AMI cases at the web site www.kamir.or.kr has been performed in 41 primary PCI centers in Korea and between November 2005 and September 2006, 1,541 surviving patients who had been implanted with either Cypher or Taxus stents were enrolled for analysis during a 6-month clinical follow-up. There were 2 groups: group I [834 patients, 61.9+/-11.9 years: sirolimus-eluting stent (Cypher)], group II [707 patients, 62.9+/-12.0 years: paclitaxel-eluting stent (Taxus)]. At both 1 and 6 months the incidence of MACE was not significantly different between the 2 groups. There were 17 cases of stent thrombosis, but the incidence of stent thrombosis was not significantly different between the 2 groups (group I:II=9 (1.1%):8 (1.1%), p=1.000). The stent type, length, number, lesion complexity and diabetes were not significant for the incidence of MACE or stent thrombosis after adjustment. CONCLUSION: MACE and stent thrombosis rates did not differ between 2 types of DES identified in Korea Acute Myocardial Infarction Registry (KAMIR). DES can be used in patients with AMI with a relatively low 6-month MACE rate.     

Angiotensin-Converting Enzyme Inhibitor,Captopril, Improves Scar Healing in Hypertensive Rats

Pathological cutaneous scars, with aberrant extracellular matrix accumulation, have multiple origins. Antihypertensive medications, such as calcium channel blockers, have been used to treat pathological scars. However, a relationship between angiotensin-converting enzyme (ACE) inhibitors, pathological scars, and blood pressure (BP) has never been reported. Here, we aimed to compare the differences in scar development and the effects of the administration of systemic ACE inhibitor on scar tissue in a normotensive rat, the Wistar Kyoto rat (WKY), a hypertensive rat, and the spontaneously hypertensive rat (SHR). Using an 8-mm punch, we created two full-thickness skin defects in a total of 32 rats (16 WKY and 16 SHR) to obtain a total of 64 wounds. We established control WKY (n = 16), captopril-treated WKY (n = 16), control SHR (n = 16), and captopril-treated SHR (n = 16) groups and started captopril (100 mg/g per day) treatment on day 21 in the appropriate groups. The BP of all groups was measured at 0, 3, and 5 weeks. The scar area was measured by histopathological examination, and scarring was expressed in terms of scar area and fibroblast and capillary counts. The expression of heat shock protein (HSP) 47, type I and III collagens, alpha-smooth muscle actin (α-SMA), Ki67, and vascular endothelial growth factor (VEGF) was investigated using immunohistochemistry. The scar area and fibroblast count were significantly higher in control SHR than in control WKY. The scar area, fibroblast count, and capillary count were significantly smaller in captopril-treated SHR than in control SHR. Immunostaining for α-SMA, Ki67, and VEGF also showed a noticeable decrease in scarring in the treated SHR compared with that in control SHR. Thus, BP affects scar development in a rat model, and an ACE inhibitor is more effective at reducing scars in hypertensive rats than in normotensive rats.     

Charlson Comorbidity Index Is an Important Prognostic Factor for Long-Term Survival Outcomes in Korean Men with Prostate Cancer after Radical Prostatectomy

Purpose

To analyze overall survival (OS), prostate cancer (PCa)-specific survival (PCaSS), and non-PCaSS according to the Charlson Comorbidity Index (CCI) after radical prostatectomy (RP) for PCa.

Materials and Methods

Data from 336 patients who had RP for PCa between 1992 and 2005 were analyzed. Data included age, preoperative prostate-specific antigen (PSA), prostate volume, clinical stage, and pathologic stage. Pre-existing comorbidities were evaluated by the CCI, and patients were classified into two CCI score categories (0, ≥1).

Results

The mean age of patients was 64.31±6.12 years. The median PSA value (interquartile range, IQR) was 11.30 (7.35 and 21.02) ng/mL with a median follow-up period (IQR) of 96.0 (85.0 and 121.0) months. The mean CCI was 0.28 (0-4). Five-year OS, PCaSS, and non-PCaSS were 91.7%, 96.3%, and 95.2%, respectively. Ten-year OS, PCaSS, and non-PCaSS were 81.9%, 92.1%, and 88.9%, respectively. The CCI had a significant influence on OS (p=0.022) and non-PCaSS (p=0.008), but not on PCaSS (p=0.681), by log-rank test. In multivariate Cox regression analysis, OS was independently associated with the CCI [hazard ratio (HR)=1.907, p=0.025] and Gleason score (HR=2.656, p<0.001). PCaSS was independently associated with pathologic N stage (HR=2.857, p=0.031), pathologic T stage (HR=3.775, p=0.041), and Gleason score (HR=4.308, p=0.001). Non-PCaSS had a significant association only with the CCI (HR=2.540, p=0.009).

Conclusion

The CCI was independently associated with both OS and non-PCaSS after RP, but the CCI had no impact on PCaSS. The comorbidities of a patient should be considered before selecting RP as a curative modality for PCa.