Antioxidant Effects of Lovastatin and Vitamin E on Experimental Atherosclerosis in Rabbits

The effects of the administration of vitamin E (10 mg/day) plus lovastatin (2 mg/day; group A, n = 10), lovastatin alone (2 mg/day; group B, n = 10), and placebo (group C, n = 10) were compared over 24 weeks in a randomized, single-blind controlled trial. All groups of rabbits received a trans fatty acid (TFA)–rich diet (5–10 g/day) for 36 weeks. Treatment with vitamin E plus lovastatin (group A) and lovastatin (group B) started after 12 week of administration of TFA-rich diet was associated with a significant but similar decline in serum cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides in both groups at 36 weeks. Lipid peroxides and diene conjugates showed a significant decline in association with a significant increase in the plasma level of vitamin E in group A rabbits at 36 weeks. However, the lovastatin group B showed a lesser but significant decrease in lipid peroxides and diene conjugates at 36 weeks, indicating that lovastatin may have antioxidant activity. In control group C, the increase in blood lipids and oxidative stress at 36 weeks was much greater than the decrease in groups A and B. After experimental lipid peroxidation at 24 weeks in all of the rabbits, 2 of 10 group B and 3 of 10 group C rabbits died due to coronary thrombosis; there were no deaths in group A. Thus antioxidant therapy with vitamin E can provide protection against death due to free radical stress. Aortic lipids and sudanophilia indicating athorosclorosis were significantly lower in groups A and B than in group C. The atherosclerotic coronary plaque sizes were significantly smaller in group A (18.5 ± 3.6 μm) than in groups B (41.6 ± 4.2 μm) and C (85 ± 6.7 μm). Aortic plaque sizes were also smaller in group A than in group B and C. It is possible that antioxidant therapy with vitamin E, as an adjunct to lipid lowering with lovastatin, can provide additional benefit in the inhibition of oxidative stress and atherosclerosis. The antioxidant activity of lovastatin has not been reported, to our knowledge. This revised version was published online in July 2006 with corrections to the Cover Date.     

Serum levels of soluble CD21 in patients with systemic sclerosis

Systemic sclerosis (SSc) is a systemic disorder that typically results in fibrosis of the skin and multiple internal organ systems. Although the precise mechanism is unknown, overproduction of extracellular matrix proteins, including collagens and fibronectins, and aberrant immune activation might be involved in the pathogenesis. The soluble cluster of differentiation 21 (sCD21) represents the extracellular portion of the CD21 glycoprotein that is released by shedding from the cell surfaces into plasma. sCD21 binds complement fragments and activates monocytes through binding to membrane CD23. The present study was undertaken to investigate the serum levels of sCD21 in patients with SSc. Serum sCD21 levels were reduced with age both in patients with SSc and normal controls. Serum sCD21 levels in patients with SSc were significantly decreased compared to those in control subjects. When we divided patients with SSc into limited cutaneous SSc (lcSSc) and diffuse cutaneous SSc (dcSSc), patients with lcSSc had lower levels of serum sCD21 than those with dcSSc. Moreover, the prevalence of pulmonary fibrosis in the patients with dcSSc inversely correlated with serum sCD21 levels. Our finding may support the notion that B-cell activation is involved in the mechanism for pulmonary fibrosis and skin sclerosis.     

Actions anchored by concepts: defective action comprehension in semantic dementia

Objective

To study the ability of patients with semantic dementia to understand actions, in order to examine the contribution of semantic memory to action comprehension.

Methods

The ability to comprehend symbolic and instrumental actions was assessed in 6 patients with semantic dementia and 10 healthy controls. The patients were also given the imitation test of meaningful and meaningless actions.

Results

In all patients with semantic dementia, comprehension of both symbolic and instrumental actions was defective. The comprehension of symbolic actions was more impaired than that of instrumental actions. Their ability to imitate other''s actions was well preserved.

Conclusion

This study showed that comprehension of action was impaired in semantic dementia, suggesting that semantic memory has an important role in comprehension of human action.When we observe people''s actions, we immediately understand what they are doing. This ability is arguably a fundamental basis for the imitation of other people''s behaviours and efficient skill learning. Recent neurophysiological studies propose that mirror neurones in the premotor and inferior parietal cortices of primates, which activate both when a monkey executes a particular action and when it observes similar actions by others, have a pivotal role in production and comprehension of action.^1,2 According to this view, direct matching between observed actions and the motor representations stored in mirror neurones is a common, crucial process. In humans, however, actions have a much more complex role in social interactions than they have in monkeys. Human actions often serve as a representational system and can convey complex and abstract concepts, as exemplified by symbolic gestures and sign languages.³ In such situations, a simple reference to motor representation is not sufficient, and conceptual knowledge presumably has an important role.Semantic dementia is a clinical syndrome characterised by the progressive breakdown of semantic memory or conceptual knowledge and the relative preservation of other cognitive domains.^4,5 Several studies provide evidence that semantic memory impairment is not modality‐specific and, in fact, object naming, single‐word comprehension, object categorisation, identification of the faces of famous and familiar people, environmental sound recognition and object use are defective in semantic dementia.^6,7,8 In this study, we investigated comprehension of action in patients with semantic dementia. If conceptual knowledge markedly contributes to comprehension of human action, this ability should be affected in patients with semantic dementia.     

Systemic sclerosis complicated with localized scleroderma-like lesions induced by Köbner phenomenon

Background

Scleroderma is a chronic disease of unknown etiology characterized by skin fibrosis and is divided into two clinical entities: systemic sclerosis (SSc) and localized scleroderma (LSc). In general, LSc is rarely complicated with SSc, but a certain portion of SSc patients manifests bilateral symmetric LSc-like lesions on the trunk and extremities.

Effects of isosorbide dinitrate on coronary and systemic circulation in children: comparison with dipyridamole]

The effects of isosorbide dinitrate (ISDN) on the coronary and systemic circulation were evaluated in comparison with the effects of dipyridamole (DP) in 8 children with histories of Kawasaki disease and angiographically normal coronary arteries. ISDN (100 micrograms/kg) was administered as an intracoronary injection. DP was administered intravenously at the rate of 0.56 mg/kg for 4 min. In the coronary circulation, DP induced a significant reduction of the afterload, resulting in an increase in cardiac output. However, the pulmonary artery pressure, pulmonary capillary wedge pressure and left ventricular end-diastolic pressure, which are related to the preload, were significantly reduced one min after the ISDN injection. The systolic blood pressure was reduced, while the heart rate was increased. The cardiac output, pressure-rate product or systemic vascular resistance showed no significant change. The systolic work index, however, was significantly reduced. In the coronary circulation, DP significantly increased the coronary sinus blood flow due to dilatation of the resistant vessels. However, ISDN significantly dilated the conductant vessels by 4.0 to 12.9% in diameter. There was, however, no change in the coronary blood flow, coronary perfusion pressure nor coronary vascular resistance. The grade of dilatation of the coronary vessels caused by ISDN was lower in children than in adults.     

Cardiac involvement and prognosis in acute mucocutaneous lymph node syndrome.

Cardiac involvement and prognosis were studied in the acute febrile mucocutaneous lymph node syndrome which recently has been found among Japanese infants and younger children. The reason for its particular predilection for the main coronary arteries and the pathologic process are discussed in relation to the pathogenesis and nutrient of the main coronary arteries.     

Sex differences in acquired cystic disease of the kidney on long-term dialysis

Acquired cystic disease of the kidney in chronic glomerulonephritic patients who had been on hemodialysis more than 3 years (4.5 +/- 1.2 years at the base line examination), were followed for 3.6 +/- 0.5 years (at the follow-up examination) by computed tomography (CT scan). The renal volume in the 25 male patients was significantly greater at the follow-up examination than at the base line examination. On the other hand, the renal volume in the 12 female patients was similar on both examinations. The enlargement of kidney volume more than twofold during the follow-up was seen in 9 of 25 male and none of 12 female patients. The grade of cystic transformation was increased in male patients during the follow-up period. These results indicate that sex-related endogenous substances might play a role in the pathogenesis of acquired cystic disease.