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Aims: It is unknown whether there is an interaction between aspirin and angiotensin receptor blockers on outcomes in patients with heart failure (HF). [ABSTRACT FROM PUBLISHER]

Editorial. Comments on the article 'Circulating Levels of Tumor Necrosis Factor Correlate With Indexes of Depressed Heart Rate Variability: A Study in Patients With Mild-to-Moderate Heart Failure' published in the March 2003 issue of the 'Chest' journal. Ways by which heart rate variability is measured; Role of Tumor necrosis factor in causing blunted heart rate variability in chronic heart failure.

Objective: Nitric oxide (NO) has been proposed as a common mediator of tumor necrosis factor-α (TNFα)-induced vasodilation and myocardial dysfunction. Accordingly, we performed an extensive assessment of the influence of NO synthase inhibition on left ventricle (LV) and circulatory performance in conscious dogs at steady state and after establishment of TNFα mediated myodepression. Methods: Autonomically blocked, chronically instrumented dogs were studied at steady state and 6 h after initiation of a 1-h rhTNFα infusion (40 μg/kg). Ventricular performance was evaluated using the pressure–volume framework. Dogs were then treated with either NG-nitro-l-arginine methylester (l-NAME, 40 mg/kg bolus) or angiotensin II (250–500 ng/kg). Results: l-NAME, under control conditions or following recombinant human (rh)TNFα-induced ventricular dysfunction, produced marked increases in afterload with attendant increases in LV pressure, volume, and prolonged isovolumic relaxation without adversely influencing coronary blood flow. Regardless of whether the dogs received rhTNFα, l-NAME did not affect the slopes of the end-systolic pressure–volume and stroke-work (SW)-end-diastolic volume (EDV) relations (force-based measure of contractility), whereas the slope of the dP/dtmax–EDV relation, a velocity dependent parameter of LV systolic function, declined. Overall ventricular performance, as seen by the circulation, was reduced by l-NAME in control as well as rhTNFα-treated dogs, evidenced by rightward shifts of the SW–EDV and dP/dtmax–EDV relations. Similar findings were observed in the separate cohorts of dogs, at steady state and 6 h after rhTNFα, following angiotensin II at matched systolic pressure. Conclusions: Systemic NO synthase inhibition with l-NAME does not acutely reverse rhTNFα-induced myocardial dysfunction. The detrimental influence of l-NAME on LV size, relaxation, and velocity-based measures of contractility is likely attributable to its effects on increasing afterload. [ABSTRACT FROM PUBLISHER]

Examines effect of elevated atmospheric carbon dioxide (CO2) on leaf anatomy and morphology of Panicum species. Changes in leaf thickness and transectional area; Decrease in abaxial stomatal frequency; Relationship between starch concentration and photosynthetic capacity; Determination of increased leaf glaucousness.

It is widely held that the albumins of pea seeds are mainly enzyme proteins. In the present study of Pisum sativum cv. Greenfeast, certain major polypeptides confined to the albumin fraction from the cotyledons were shown to be degraded in vivo following germination, thus functioning as a reserve of amino nitrogen and carbon skeletons. A general definition of seed storage proteins is proposed, to encompass any protein present in major quantity in the seed which is degraded following imbibition, and for which no other function may be demonstrated. [ABSTRACT FROM AUTHOR]

Discusses previous studies regarding the effect of carbon dioxide on plant processes. Stomatal opening and closing; Stomatal density; Inhibition of respiration; Root morphogenesis; Flowering; Yield and limiting factors; Effect on seed parameters.

Pea plants (Pisum sativum 1,. cv. Melbourne Market), each with a single developing pod, were pulse-fed [4- 14C]aspartate through the cut stem at stages from 11 to 32 d after full blossom. The distribution of radioactivity in soluble metabolites of the hull, seedcoats, embryo sac liquid and embryo was determined by 2-dimensional paper chromatography and radioautography after feeding intervals of 6 h, 24 h or 48 h. At the earliest stage, radioactivity was recovered mainly in sucrose, serine, homoserine and threonine in the hull. At the 15-16 d stage, threonine became the major derived amino compound secreted into the embryo sac, and sucrose became the predominant derivative recovered from both hull and seed tissues. Stem-fed aspartate can therefore be transferred to stem phloem, and sucrose synthesized from aspartate in stems and leaves ran be transferred to phloem in both organs. [ABSTRACT FROM AUTHOR]