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The aim of this research is to evaluate the influence of the moisture content of wood on stress wave velocity, as a nondestructive technique for estimating the mechanical properties of gross cross-section Spanish Scots pine (Pinus sylvestris) lumber for structural use. 26 100 x 150 x 3000 mm pieces from Segovia, Spain, were tested with different moisture content values, from 35,5 to 9%. Measurements of longitudinal stress wave velocity were carried out during the natural drying process by using three commercial portable devices based on ultrasonic, acoustic and vibrational techniques. The results can be summarized as three percentage points of decreasing velocity per percentage point of increased wood moisture content in the range from 11,8 to 21,4%: 0,48% for ultrasonic, 0,50% for acoustic wave and 0,65% for longitudinal vibration. [ABSTRACT FROM AUTHOR]

Background and Purpose: The aim of this study was to investigate the effect of chronic treatment with antihypertensive and non-antihypertensive doses of zofenopril on cardiovascular changes in spontaneously hypertensive rats (SHR).Experimental Approach: Male SHR were treated with 0.5 or 10 mg kg(-1) per day of zofenopril (Z(0.5) and Z(10)) for 3 months. SHR and Wistar-Kyoto rats (WKY) receiving vehicle were used as controls. Systolic blood pressure was measured using the tail cuff method. Left ventricular weight/body weight ratio was calculated as cardiac hypertrophy index. Angiotensin converting enzyme (ACE) activity was determined in plasma and tissues by a fluorimetric method. Vascular reactivity was evaluated on aortic rings by acetylcholine and sodium nitroprusside relaxations. Effects on vascular structure were assessed by lumen diameter, wall thickness and medial cross-sectional area determination. Superoxide anion generation was quantified using lucigenin-amplified chemiluminescence in aorta.Results: Long-term daily administration of zofenopril (10 mg kg(-1)) to SHR reduced blood pressure to WKY values, decreased cardiac hypertrophy, improved the acetylcholine-induced relaxant response and reversed the vascular remodelling. ACE inhibition and antioxidant activity were involved in these effects. 0.5 mg kg(-1) per day of zofenopril slightly modified blood pressure and the other effects were weaker.Conclusions and Implications: Antihypertensive effects of chronic treatment with zofenopril were accompanied by recovery of endothelial function and improvement of cardiovascular structure. Low-dose zofenopril had little effect on blood pressure, with some benefits on cardiovascular structure and function. Inhibition of ACE and antioxidant activity were involved in these effects. [ABSTRACT FROM AUTHOR]

Background and Purpose: This study investigates the effect of pravastatin on blood pressure, cardiovascular remodelling and impaired endothelial function induced as early signs of cardiovascular disease in young spontaneously hypertensive rats (SHR).Experimental Approach: Eight-week-old SHR were treated for 4 weeks with pravastatin (20 mg kg(-1) day(-1)). Systolic blood pressure was measured periodically during the study using the tail-cuff method. At the end of the study, the left ventricular weight /body weight ratio was used as an index of left ventricular hypertrophy (LVH). Vascular function, superoxide (O(2)(-*)) production and structure were studied in aortic rings. Lipid peroxidation was measured in plasma (thiobarbituric acid reactive substances assay).Key Results: Systolic blood pressure was lower in treated SHR than in control SHR, at the end of the study (171 +/- 1 vs. 159 +/- 2 mmHg, P < 0.05), and LVH was significantly reduced by pravastatin (2.7 +/- 0.02 vs. 2.5 +/- 0.01 mg g(-1), P < 0.05). Vascular responses to sodium nitroprusside and phenylephrine were similar in both groups; nevertheless, the relaxation response to acetylcholine was higher in the treated rats (45.6 +/- 2.6 vs. 58.1 +/- 3.2 %, P < 0.05). Vascular O(2)(-*) and plasma thiobarbituric acid reactive substances were reduced by pravastatin treatment, and urinary nitrites was elevated. Finally aortic wall became thinner after pravastatin treatment.Conclusions and Implications: Chronic treatment with pravastatin attenuated the increase of systolic blood pressure in SHR, prevented early LVH and improved vascular structure and function. These effects were accompanied by decreased measures of oxidative stress and improvements in NO production. [ABSTRACT FROM AUTHOR]