bluuebunny/crossref_metadata_2025 huggingface dataset:
Interaction between cyclooxygenase and the renin-angiotensin-aldosterone system: rationale and clinical relevance
Authors: Meune Christophe , Mourad Jean-Jacques , Bergmann Jean-François , Spaulding Christian
Published: May 2007

Increased understanding of pathophysiological mechanisms of cardiovascular diseases has shown that the renin-angiotensin-aldosterone system (RAAS) is activated in this setting and suggests a central role for the angiotensin-converting enzyme (ACE). ACE transforms angiotensin I (Ang I) to angiotensin II (Ang II), and also promotes the degradation of bradykinin into inactive metabolites. These bradykinins stimulate nitric oxide synthesis and vasodilatator prostaglandin synthesis via a cyclooxygenase (COX) pathway.

COX inhibitors may therefore be deleterious in cardiovascular disease and/or counteract part of ACE inhibitor (ACE-I) efficacy. This has been clearly demonstrated with non-steroidal anti-inflammatory drugs (NSAIDs), including high-dose aspirin, in avoiding their use in such patients. hypertension, coronary artery disease and chronic heart failure (CHF); most guidelines recommend avoiding their use in such patients.

Theoretically, this effect is dose-mediated and the existence of an identical deleterious effect with low-dose aspirin has been an area of intense debate. In this article, we review studies, most of them conducted in CHF, that pointed out such a possible deleterious effect and a counteraction of ACE-Is with low-dose aspirin , using various criteria of assessment.

However, there are no prospective long-term studies that have validated such an effect, and the role of other anti-aggregating agents has not been evaluated. Until such studies are published, the use of low-dose aspirin (100 mg/day) in such patients can be recommended.
Mineralocorticoid receptor blockade: new insights into the mechanism of action in patients with cardiovascular disease
Authors: Pitt Bertram , Stier Charles T , Rajagopalan Sanjay
Published: May 2007

Mineralocorticoid receptor (MR) blockade is effective in reducing total mortality and the incidence of heart failure in patients with systolic left ventricular dysfunction (SLVD) associated with chronic heart failure or post myocardial infarction.

Pre-clinical and clinical studies in SLVD have shown that MR blockade reduces sudden cardiac death, left ventricular remodelling, left ventricular hypertrophy, endothelial dysfunction, autonomic imbalance, renal dysfunction and improves fibrinolysis.

While MR blockade promotes sodium excretion and the combination of an angiotensin-converting enzyme inhibitor and a MR blocker have been shown to be more effective than either alone in causing natriuresis, it is unlikely that their beneficial effects can be explained solely on this basis.

Aldosterone has been shown to have a number of adverse effects, including activation of other neurohumeral mediators, stimulation of active reactive oxygen species (ROS), activation of the NF-κβ and AP-1 signalling pathways, vascular inflammation and fibrosis, myocardial hypertrophy, autonomic imbalance, and a decrease in fibrinolysis. MR blockade is, however, effective both in situations with and without an increase in serum aldosterone level, since the MR can be occupied and activated by cortisol as well as by aldosterone.

In view of these mechanisms, MR blockade may play an important role not only on SLVD, but also in essential hypertension with normal systolic function, diastolic heart failure, valvular heart disease, vascular stiffening with ageing, progression of renal disease, and diabetes mellitus. This hypothesis will, however, require further prospective evaluation.
Blocking the renin-angiotensin-aldosterone system or lowering the blood pressure: does EUROPA help?
Authors: Mackay Judy A
Published: May 2007

The EUropean trial on Reduction Of cardiac events with Perindopril in stable coronary Artery disease (EUROPA) demonstrated that the angiotensin-converting enzyme inhibitor, perindopril, compared with placebo, in patients with established coronary artery disease, reduced cardiovascular endpoints by 20% over a four-year follow-up period. Although the authors of this study claim that the risk reduction was best explained by blockade of the renin-angiotensin-aldosterone system, reference to recent meta-analyses of blood pressure (BP)-lowering trials provides compelling evidence that the benefits observed in the trial could be explained by the 5/2 mmHg BP difference between active and placebo treatments.
Review: Role of the selective aldosterone receptor blockers in arterial hypertension
Authors: Sierra Cristina , Ruilope Luis M
Published: May 2007

Aldosterone can cause cardiovascular injury in animals and men. The aldosterone blocker, spironolactone, has been shown to reduce mortality in patients with congestive heart failure. The use of this drug in arterial hypertension has been limited by the high frequency of adverse effects. Recently published data with a new aldosterone blocker, eplerenone, have confirmed the benefits of aldosterone blockade in patients post-myocardial infarction, as well as in the regression of left ventricular hypertrophy in hypertensive patients and of microalbuminuria in Type 2 diabetic patients. The fact that eplerenone is much better tolerated open the possibility of this therapy in cardiovascular, as well as in renal disease.
A rare combination consisting of aldosterone-producing adenoma and adrenal myelolipoma in a patient with heterozygosity for retinoblastoma (RB) gene
Authors: Caliumi Chiara , De Toma Giorgio , Bossini Alfredo , Cianci Rosario , Bosman Cesare , Genuardi Maurizio , Cerci Sabrina , Letizia Claudio
Published: May 2007

Various pathological disorders have been associated with primary aldosteronism, including glucagonoma, phaeochromocytoma and primary hyperparathyroidism.

In this report, a case of adrenal myelolipoma (a rare non-functioning tumour composed of mature adipose tissue and normal haematopoietic elements similar to bone marrow cells), aldosterone-producing adenoma and a pituitary microadenoma coexisting in a 62-year-old man with a 15-year history of arterial hypertension, previous ablation of an autonomously-functioning thyroid adenoma, multiple lipomas and an heterozygosity of the retinoblastoma (RB) susceptibility gene is reported.

We believe that this case probably represents another variant of the multiple neoplasia syndrome and we speculate that structural alteration of the RB gene may play a role in the tumorogenesis.
Tonic levels of angiotensin II reduce tonic levels of vascular nitric oxide even in salt-replete man
Authors: Sim Justein SN , Farquharson Colin , Struthers Allan D
Published: May 2007

Introduction

Losartan improves stimulated endothelial function in patients with cardiovascular disease, but there are no data to establish whether losartan has this effect in normal man. Furthermore, whether losartan improves basal nitric oxide (NO) activity is controversial. We therefore examined whether treatment with losartan improved basal NO activity in normal, salt-replete man. If so, this would imply that tonic levels of angiotensin II (Ang II) reduce tonic basal levels of NO, even in salt-replete normal man.

Methods

We performed a randomised, placebo-controlled, double-blind crossover study in 24 healthy volunteers, comparing losartan 50 mg daily for one month versus placebo. Brachial artery endothelial function was assessed by bilateral venous occlusion plethysmography, measuring the response to intra-arterial infusions of the endothelial-dependent and endothelial-independent vasodilators, acetylcholine and sodium nitroprusside respectively and the endothelial-dependent vasoconstrictor NG-monomethyl-L-arginine. Results were analysed by multiple analysis of variance and statistical significance was taken as a p value of ≤ 0.05.

Results

Losartan significantly increased the vasoconstriction in response to N G-monomethyl-L-arginine (-37 2% vs. -32+2%, losartan vs. placebo; p=0.05). Losartan improved the vasodilatation response to acetylcholine; however, this result did not reach significance (214+2 0% vs. 174+20%, losartan vs. placebo; p=0.15). Losartan did not affect the response to nitroprusside (172+15% vs. 176+16%, losartan vs. placebo; p=0.84). There was no significant difference in blood pressure between the two study days.

Conclusions

Losartan improves basal NO bioactivity in healthy salt-replete volunteers. Even in salt-replete man, basal Ang II levels exert a tonic effect, which reduces basal NO.
Reassessing guidelines for heart failure
Authors: Drexler Helmut , Wollert Kai C
Published: May 2007

Significant progress has been made in the last few years in the management of heart failure. In particular several trials have given significant results. It has become apparent that heart failure may be prevented in some patients by treatment of risk factors such as coronary artery disease.

Experience with angiotensin-converting enzyme (ACE) inhibitors has shown that the survival and symptomatic benefits do last in the long term, and confirm that they are the first-line treatment in heart failure.

The results of a number of trials using the angiotensin receptor blockers (ARBs) candesartan, valsartan and losartan are presented and discussed. There is also some experience now in the use of candesartan for patients with heart failure and preserved left ventricular systolic function.

The COMET trial compared the β-blockers carvedilol and metoprolol tartrate, and suggests that there may be differences in clinical effect between β-blockers.

The selective aldosterone receptor blocker eplerenone was evaluated in the EPHESUS trial in post-MI patients with signs of heart failure.

Based on these clinical trials, heart failure guidelines are now being updated.
Statin therapy increases vascular sensitivity to angiotensin II in hypercholesterolaemic patients
Authors: Sim Justein SN , Dick John BC , Struthers Allan D
Published: May 2007

Introduction Cross-talk between various cardiovascular risk factors has been suggested by a number of studies. This study examines the interaction between hypercholesterolaemia and the renin-angiotensin system in vivo in man.

Methods We performed a randomised, placebo-controlled, double-blind crossover study on 40 hypercholesterolaemic patients, comparing cholesterol-lowering therapy with a statin for six months versus placebo. Brachial artery function was assessed by bilateral venous occlusion plethysmography using intra-arterial infusions of the endothelial-dependent vasoconstrictors, angiotensin I (Ang I) and angiotensin II (Ang II), to measure vascular angiotensin-converting enzyme (ACE) and Ang II receptor response respectively. The endothelial-independent vasoconstrictor, noradrenaline, was used as a control vasoconstrictor. Results were analysed by multiple analysis of variance and statistical significance

Cholesterol-lowering treatment with a statin was taken as a p value <0.05. Results Cholesterol-lowering treatment with alstatin significantly reduced the mean total cholesterol level to 5.71 mmol/L vs. 7.57 mmol/L on placebo (p<0.0001). Hypercholesterolaemia significantly increased the vasoconstriction response to noradrenaline (placebo versus statin treatment; p=0.046). In hypercholesterolaemia, there was a strong trend towards a reduction in the vasoconstriction response to Ang I (placebo versus statin treatment; p=0.089). In hypercholesterolaemia, the vasoconstriction response to Ang II was significantly reduced (placebo versus statin treatment; p=0.01).

Conclusions Our in vivo results show that, unlike some other previous work, hypercholesterolaemia is associated with down-regulation of the vasoconstrictor response to Ang II and that statin therapy up-regulates the local vasoconstrictor response to Ang II. The possibility now arises that, in man, statins alter the balance between AT1-receptors and AT2-receptors.
Prevention of recurrences in patients with lone atrial fibrillation. The dose-dependent effect of angiotensin II receptor blockers
Authors: Madrid Antonio H , Marín Irene Marín , Escobar Cervantes Carlos , Bernal Morell Enrique , Escudero Estévez Jaime , Moreno Gerardo , Rondón Parajón Jorge , Jian Peng  , Limón Lilianna , Nannini Sebastian , Moro Concepción
Published: May 2007

Background

Atrial fibrillation (AF) leads to the activation of the renin-angiotensin system (RAS), which seems to play an important role in atrial remodelling. It is not known yet whether RAS blockade may prevent recurrences in patients with lone AF.

Methods and results

Patients with an episode of persistent AF for >7 days, in the absence of cardiac or extracardiac causes and with normal blood pressure values (`lone AF'), were recruited. Ninety patients were randomised and scheduled for electrical cardioversion. Three groups of patients were compared: Group I was treated with amiodarone 400 mg daily (30 patients), group II was treated with amiodarone 400 mg daily plus irbesartan 150 mg daily (30 patients) and group III with amiodarone 400 mg daily plus irbesartan 300 mg daily (30 patients). The primary endpoint was the time to a first recurrence of AF. The patients were cardioverted and followed. The Kaplan-Meier analysis of time to first recurrence during the follow-up period showed that patients treated with amiodarone 400 mg plus irbesartan 300 mg had a greater probability of remaining free of AF (77% vs. 52% for amiodarone and 65% for amiodarone+irbesartan 150 mg), hazard 0.27—0.82; p=0.001). ratio for a recurrence in group III: 0.47 (95% CI

Conclusions

The combination of irbesartan plus amiodarone decreased the rate of AF recurrences, with a dose-dependent effect, in lone AF patients.
Angiotensin II may mediate apoptosis via AT1-receptors in the rat cardiac conduction system
Authors: Vongvatcharanon Uraporn , Vongvatcharanon Surapong , Radenahmad Nisaudah , Kirirat Pornpimol , Intasaro Pranom , Sobhon Prasert , Parker Terry
Published: May 2007

Introduction

Apoptosis and angiotensin II (Ang II) have been suggested as possible causes of arrhythmias. In addition, Ang II via Ang II type I (AT1-) receptors, has been demonstrated to induce cardiomyocyte apoptosis. The transgenic m(Ren-2)27 (TG) rat carries the additional Ren-2 gene, the expression of which results in an increase in cardiac Ang II, thus potentially affecting the cell growth/death equilibrium. In this study we have investigated the effect of Ang II, via AT1-receptors, on mediating apoptosis in a cardiac conduction system (SA node and AV nodes).

Materials and methods

Heart sections from male two-day, one-week and two-week TG and Sprague-Dawley (SD) rats were stained with Masson Trichrome to localise the SA and AV nodes. The sections containing SA or AV nodes were processed for quantitation of apoptotic nuclei and AT1-receptors.

Results

The number of apoptotic nuclei/mm2 in the SA and AV nodes were found to decrease from two days to two weeks in both the TG and the SD rats, and the number of apoptotic nuclei/mm2 in the TG groups was significantly higher than that of the SD groups for all ages (p<0.05). The number of AT1-receptors/mm2 in the SA node were found to decrease with increasing age, whereas the number of AT1-receptors/mm 2 in the AV node was increased in both TG and SD rats and the number of AT1-receptors/mm2 in the three TG groups was significantly more than that of the three SD groups (p<0.05).

Discussion and conclusion

As a consequence of the additional renin gene in the TG rats, which results in the alteration of the local renin-angiotensin system, the numbers of AT1-receptors/mm 2 and apoptotic nuclei/mm2 are increased. The number of apoptotic nuclei/mm2 and AT1-receptors/mm2 in the SA node decrease with maturation, whereas, the number of AT1-receptors in the AV node increase. Thus, there may be a correlation between Ang II and apoptosis in the SA node, which does not appear to be present in the AV node.
Renal targeting of captopril using captopril-lysozyme conjugate enhances its antiproteinuric effect in adriamycin-induced nephrosis
Authors: Windt Willemijn AKM , Prakash Jai , Kok Robbert Jan , Moolenaar Frits , Kluppel C Alex , de Zeeuw Dick , van Dokkum Richard PE , Henning Robert H
Published: May 2007

Introduction

High-sodium intake blunts the renoprotective efficacy of angiotensin-converting enzyme (ACE) inhibitors. We investigated whether targeting the drug to the kidneys may attenuate the inferior response to ACE inhibitor (ACE-I) under high-sodium conditions. The ACE-I, captopril, was coupled to the low molecular weight protein (LMWP) lysozyme, yielding captopril-lysozyme conjugates that accumulate specifically in the proximal tubular cells of the kidneys.We compared the antiproteinuric efficacy of captopril to that of the captopril-lysozyme conjugate in adriamycin-induced proteinuric rats fed with a high-sodium diet.

Materials and methods

Rats with adriamycin (single injection 2 mg/kg)-induced proteinuria were put on a high-sodium diet (HS; 3% NaCl). When stable proteinuria developed at 5.5 weeks, animals were assigned to the following subcutaneous treatments: (1) vehicle (n=7); (2) lysozyme (equivalent to the amount in conjugate) (n=7); (3) captopril (5 mg/kg/24 hours) (n=8); (4) captopril-lysozyme conjugate (captopril content equivalent to 1mg captopril/kg/24 hours) (n=7). Blood pressure and proteinuria were monitored. After 10 days of treatment the rats were sacrificed and kidneys and plasma were removed.

Results

Results are given as mean + S.E.M. After injection with adriamycin at t=0, stable proteinuria developed, amounting to 547+79 mg/24 hours at week 5.5. Subsequently, after seven and nine days of treatment, no reduction of proteinuria was observed in the captopril-treated group. In contrast, a significant reduction in proteinuria, amounting to 35+4% (day seven) and 25+2% (day nine), was observed in the captopril-lysozyme conjugate group (p<0.05 compared with the captopril group). In contrast, blood pressure was reduced in the captopril-treated group by 13.9+2.9 mmHg, while in the captopril-lysozyme treated group, an increase of 7.9+3.3 mmHg was found. Renal ACE activity was lowered by 30% in the captopril, as well as in the captopril-lysozyme conjugate treated group, compared with control. Furthermore, the ratio of kidney: plasma levels of captopril almost doubled as a consequence of coupling to lysozyme.

Conclusion

In proteinuric rats fed with a high-sodium diet, captopril induced a reduction in blood pressure without an effect on proteinuria. In contrast, renal targeting of a five times lower dose of the ACE-I with the captopril-lysozyme conjugate reduced proteinuria without reducing blood pressure. Therefore, renal targeting of ACE-I may be a promising strategy to optimise the therapeutic response of ACE-I.
The DIabetic REtinopathy Candesartan Trials (DIRECT) Programme: baseline characteristics
Authors:   The DIRECT Programme Study Group
Published: May 2007

Renin-angiotensin system blockade has been shown to be superior to other antihypertensive therapy in slowing progression of renal disease in diabetic patients, but questions remain regarding diabetic retinopathy. The primary objective of the DIabetic REtinopathy Candesartan Trials (DIRECT) Programme is to examine primary (incidence) and secondary (progression) prevention of diabetic retinopathy when blocking angiotensin II type 1-receptors with candesartan in normoalbuminuric, normotensive Type 1 diabetic patients, and secondary prevention only in normoalbuminuric, normotensive or treated hypertensive Type 2 diabetic patients. The secondary objectives include examining the effect of candesartan treatment on urinary albumin excretion rate (UAER) in each of the three studies and to examine the incidence of proliferative retinopathy in all three populations combined.

Standardised investigations for patients at enrolment include blood pressure measurement analysis of HbA1C and serum lipids, and a detailed ophthalmological examination. Retinopathy and UAER outcomes are assessed yearly. Retinopathy is graded centrally, based on seven-field stereo photographs using the Early Treatment Diabetic Retinopathy Study (ETDRS) protocol. Randomisation was performed when the results of retinal gradings were available, and treatment with 16 mg candesartan cilexetil or matching placebo was initiated; the dose was increased to 32 mg after one month. Calculations of UAER are based on two timed overnight urine collections.

A sample size re-assessment was carried out when approximately 70% of the patients had been randomised in the DIRECT Programme to ensure the results to be conclusive.

In total, 5,231 patients were randomised in the DIRECT Programme in 30 countries. One thousand, four hundred and twenty one and 1,905 patients are evaluated in the primary and secondary prevention studies in Type 1 diabetes, respectively and 1,905 patients in the secondary prevention study in Type 2 diabetes.

HbA1C showed mean values of 8.1, 8.5 and 8.2% for the Type 1 primary, Type 1 secondary and Type 2 secondary prevention studies, respectively. In the Type 1 secondary prevention study, 49% of the patients had mild nonproliferative retinopathy (level 20) in at least one eye, and 9% had moderate-moderately severe non-proliferative retinopathy (level 43—47). In Type 2 patients, 17% had level 43—47 and the remainder less severe retinopathy.
Additive effects of endothelial progenitor cells combined with ACE inhibition and β-blockade on left ventricular function following acute myocardial infarction
Authors: Boyle Andrew J , Schuster Michael , Witkowski Piotr , Guosheng Xiang  , Seki Tetsunori , Way Kerrie , Itescu Silviu
Published: May 2007

Animal studies have demonstrated the efficacy of endothelial progenitor cells (EPCs) in preventing left ventricular (LV) remodelling following myocardial infarction (MI). Preliminary human studies are underway, yet no studies have demonstrated efficacy in combination with standard medical therapy, i.e. angiotensin-converting enzyme (ACE) inhibitors and β-blockers. Nude rats underwent left anterior descending coronary artery ligation to induce MI. Animals were randomised to receive no treatment (MI, n=5), quinapril 200 mg/L + metoprolol 2 g/L (ACE/BB, n=5), two million EPCs intravenously (EPC, n=5)or both (ACE/BB + EPC [n=5]), then sacrificed after two weeks treatment. ACE/BB resulted in a 75% reduction in fibrosis in the region remote from the MI (p<0.05), but EPC therapy had little effect here. Conversely, EPC therapy induced neovascularisation at the peri-infarct rim, thereby preventing peri-infarct apoptosis by 81% (p<0.05). Acting via different but complementary mechanisms, the combination of ACE/BB + EPCs resulted in a greater overall improvement in LV function on echocardiography than either therapy alone. Clinical trials using stem cell therapy in conjunction with standard medical treatment are warranted.
Review: Preventing End-Stage Renal Disease in Diabetic Patients — Dual Blockade of the Renin-Angiotensin System (Part II)
Authors: Jacobsen Peter Karl
Published: May 2007

Diabetic nephropathy is a major cause of diabetes related morbidity and mortality. The first part of the current review was published in the last issue of this journal and discussed the impotant role of the renin-angiotensin system (RAS) in diabetic nephropathy and the genetic influence on development of end-stage renal disease (ESRD) in diabetic patients. This second part of the review focus on the potential improvement of the current treatment strategy to slow down the loss of kidney function using dual blockade of the RAS with both ACE-inhibitors (ACE-I) and angiotensin II receptor blockers (ARBs). Substantial evidence from short-term studies using surrogate endpoints indicates a beneficial impact of dual blockade of the RAS, not obtainable with single agent blockade alone, both in diabetic and non-diabetic renal disease. This conclusion has been confirmed and extended in a longterm trial with regard to prevention of ESRD in non-diabetic renal disease. Results indicate that dual blockade of the RAS may further slow down, but not arrest progressive loss of renal function. However, studies defining the optimal dose of ACE-I / ARBs without additional adverse effects are essential to ensure relevant comparison with dual blockade therapy. Trials using primary renal endpoints in diabetic nephropathy are still needed, and will finally establish the role of dual blockade of the RAS in a clinical setting.
Implications of CIBIS III: A Commentary
Authors: Willenheimer Ronnie
Published: May 2007

Combined therapy with optimum doses of a beta-blocker and an angiotensin-converting enzyme inhibitor (ACE-I) is the mainstay for the treatment of chronic heart failure (CHF). However, patients cannot be started on full doses of both drugs and treatment has to be initiated one way or the other. The Cardiac Insufficiency Bisoprolol Study (CIBIS) III was the first trial investigating the optimum sequence of initiating treatment of CHF, in terms of mortality and morbidity. CIBIS III compared randomised, open-label initial monotherapy with bisoprolol or enalapril for six months, followed by their combination for six to 24 months, in 1,010 patients at least 65 years of age, with stable, mildly or moderately symptomatic, systolic CHF. The two strategies were similarly efficacious in terms of the combined primary endpoint of mortality or all-cause hospitalisation, and showed similar safety. The bisoprolol-first approach showed a 28% lower mortality at the end of the monotherapy phase (p=0.24) and a 31% lower mortality at the end of the first year (p=0.06), but a 25% increase in worsening of CHF events (p=0.23). The main conclusion is that, CHF therapy may be started with bisoprolol or enalapril in patients like those in CIBIS III. However, it may be argued that the primary therapeutic goal in the early phase of CHF should be improved survival, whereas the long-term aim, achievable during combined therapy with optimum doses of several drugs, should be improved quality of life, physical function, morbidity and survival. In such case, the CIBIS III findings would tend to support starting CHF therapy with bisoprolol rather than enalapril in stable patients with mild or moderate symptoms.
Review: Brain Aminopeptidases and Hypertension
Authors: Banegas Inmaculada , Prieto Isabel , Vives Francisco , Alba Francisco , de Gasparo Marc , Segarra Ana Belen , Hermoso Francisco , Durán Raquel , Ramírez Manuel
Published: May 2007

The brain aminopeptidases that participate in the enzymatic cascade of the renin-angiotensin system play a major role in blood pressure (BP) control, and their study offers new perspectives for the understanding of central BP control and the treatment of hypertension. In this system, angiotensin II is converted to angiotensin III (Ang III) by glutamyl aminopeptidase (GluAP) and Ang III is further metabolised to angiotensin IV by alanyl aminopeptidase or arginine-aminopeptidase. It is now clear that Ang III is the key active form of the central angiotensins, exerting tonic stimulatory control over BP Therefore, the development of GluAP inhibitors as potential antihypertensive agents offers new perspectives for therapy. Brain aspartyl JR aminopeptidase, which converts angiotensin I to angiotensin 2-10, is also a possible target for antihypertensive therapy because of its potential role in BP control. Finally, since changes in BP levels, that paralleled changes in brain and plasma aminopeptidase activities, were observed after unilateral lesions of the nigrostriatal system, brain asymmetry, aminopeptidase activities and BP control appear to be related, resulting their interplay in an asymmetrical neuroendocrine response that differentially affect BP control.The study of this interaction may contribute to our understanding of how the brain controls BP
Review: Imidapril in Heart Failure
Authors: Dolezal Tomas
Published: May 2007

Angiotensin-converting enzyme (ACE) inhibitors improve the prognosis in mild, moderate and severe heart failure, as well as preventing the onset of heart failure in patients with chronic asymptomatic left-ventricular dysfunction and in those with reduced ejection fraction after myocardial infarction (MI). Imidapril is a long-acting ACE inhibitor that is rapidly converted in the liver to its active metabolite, imidaprilat. Maximum plasma concentrations of imidapril and imidaprilat are achieved after 2 and 5—6 hours, respectively, with corresponding elimination half-lives of 1.1—2.5 and 10—19 hours. Imidapril is used in the treatment of hypertension, chronic heart failure, acute MI and diabetic nephropathy. In patients with mild-tomoderate chronic heart failure, imidapril 10 mg once-daily increased exercise time and physical working capacity, decreased plasma atrial natriuretic peptide and brain natriuretic peptide levels and reduced blood pressure. It also improved left ventricular ejection fraction, being significantly more effective than bisoprolol, in patients with acute MI. Imidapril is well tolerated and preliminary studies suggest it has an advantage over captopril and enalapril in terms of a lower incidence of cough. In conclusion, imidapril is a well-investigated versatile ACE inhibitor for the treatment of a range ofACE inhibitor for the treatment of a range of cardiovascular diseases.
On the persistence of positive events in life scripts
Authors: Erdoğan Ahu , Baran Bengi , Avlar Billur , Taş A. Çağlar , Tekcan Ali İ.
Published: May 2007

The life script account of the reminiscence bump in autobiographical memories suggests that cultural expectations about the nature and timing of transitional events lead to the bump. The empirical evidence for life scripts is limited. We tested the generality of the life script by looking at the effects of culture, gender and cohorts. Turkish participants were asked (a) to list the seven most important events a newborn or an elderly would experience during his/her lifetime and (b) to estimate the prevalence, importance, age‐at‐event and emotional valence of each event. We obtained a clear life script containing more positive than negative events; there was also stronger agreement about the timing of positive than of negative events. The life script for this sample overlapped substantially with earlier data from Denmark. Events and their characteristics were not influenced by the gender of either the participants or the target person. Finally, many aspects of the life script, but not the bump, changed depending on for whom the script was constructed (newborn vs. elderly). Copyright © 2007 John Wiley & Sons, Ltd.
Effects of rote versus gist strategy on the verbatim retention of theatrical scripts
Authors: Noice Helga
Published: May 2007

The research reported here investigated the relative efficiency of rote and gist strategies in the learning of theatrical scripts. Two conditions (rote and gist) and two subject populations (professional actors and psychology students) were used in both immediate and delayed testing. A new scoring scheme to determine accuracy of recall was devised using strict, moderately strict, and lenient measures of accuracy. The primary finding was that a gist strategy led to better literal recall even for material that needed to be remembered verbatim. However, while recall was approximately equal for actors and students in the gist condition, actors' performance was less depressed by the constraints of the rote condition which minimized the possibility of processing for meaning. Post‐test statements of subjects' strategies were analyzed for commonalities. Actors and students in the gist condition pursued similar strategies but with different goals and different emphases. Statements by subjects in the rote condition revealed attempts by actors but not by students to relate speeches currently being repeated to antecedent material.
Route‐finding: A measure of everyday executive functioning in the head‐injured adult
Authors: Boyd Thomas M. , Sautter Scott W.
Published: May 2007

This is an ecological test of adaptation in head‐injured adults, reporting reliability and validity of the Executive Function Route‐finding Task (EFRT; Boyd and Sautter, 1985). A Likert scale was used to rate executive aspects of route‐finding such as task formulation, strategy of approach, detection and correction of errors, and dependence on cueing among 31 head‐injured young adults within a large rehabilitation facility. The Task has high inter‐rater reliability and acceptable concurrent validity with other neuropsychological constructs.
SMC framework in motion control systems
Authors: Şabanoviç A.
Published: May 2007

Design of a motion control system should take into account both the unconstrained motion performed without interaction with environment or another system, and the constrained motion where the system is in contact with environment or has certain functional interactions with another system. In this paper control systems design approach, based on siding mode methods, that allows selection of control for generic tasks as trajectory and/or force tracking as well as for systems that require maintaining some functional relation—like bilateral or multilateral systems, establishment of virtual relation among mobile robots or control of haptic systems—is presented. It is shown that all basic motion control problems—trajectory tracking, force control, hybrid position/force control scheme and the impedance control—can be treated in the same way while avoiding the structural change of the controller and guaranteeing stable behaviour of the system. In order to show applicability of the proposed techniques simulation and experimental results for high precision systems in microsystems assembly tasks and bilateral control systems are presented. Copyright © 2007 John Wiley & Sons, Ltd.
Application of Fourier transform infrared spectroscopy to study the interactions of poly(acrylic acid) and mixtures of poly(acrylic acid) and polyacrylamide with bone powders and hydroxyapatites
Authors: Moharram M. A. , Allam Mousa A.
Published: May 2007

Fourier transform infrared (FTIR) spectroscopy was used to study the interactions of aqueous solutions of poly(acrylic acid) (PAA) and mixtures of aqueous solutions of PAA and polyacrylamide (PAAm) with chemically and thermally treated bone powders (BPs) and two commercial hydroxyapatites (HAs). An analysis of the spectra of the precipitates that resulted from the mixtures of PAA and the chemically treated samples of BP revealed that the spectra exhibited three new bands at 1544, 1552, and 1661 cm−1. The first band was attributed to the formation of calcium–polycarboxylate resulting from the interaction between the carboxylic acid groups of PAA and the calcium ions of BP. The appearance of the other two bands, in addition to the disappearance of the band corresponding to the absorption of the acid groups of PAA, provided strong evidence for the existence of other interactions between the carboxylic acid groups and the amide groups of the organic matrix of BP. On the other hand, the FTIR spectra of the samples that resulted from the mixture of PAA and thermally treated BP and the two commercial HAs showed only a new absorption band at 1544 cm−1. The interactions of mixtures of the aqueous solutions of PAA and PAAm, adjusted at low or high pH values, with the different BPs and HAs were examined. The mixtures of the aqueous solutions of PAA and PAAm interacted with the different BPs and two HAs, resulting in the formation of ternary PAA–BP–PAAm and PAA–HA–PAAm complexes. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Blowing bubbles: An aquatic adaptation that risks protection of the respiratory tract in humpback whales (Megaptera novaeangliae)
Authors: Reidenberg Joy S. , Laitman Jeffrey T.
Published: May 2007

Cetaceans (whales, dolphins, and porpoises) have developed extensive protective barriers to exclude water or food from the respiratory tract, including valvular nostrils, an intranarial elongated larynx, and a sphincteric soft palate. A barrier breach can be lethal, as asphyxiation may occur from incursions of water (drowning) or food (choking). Humpback whales (Megaptera novaeangliae), however, exhibit a possibly unique and paradoxical behavior concerning respiratory protection: they release a “bubble cloud” (a cluster of tiny bubbles) underwater from the mouth. How they do this remains unclear. This study tests the hypothesis that the larynx plays a role in enabling bubble cloud emission. The anatomy and position of the larynx was examined in seven specimens of Megaptera novaeangliae. Results indicate that the epiglottis can be manually removed from behind the soft palate and placed in the oral cavity during dissection. Unlike that of toothed whales (odontocetes), the humpback whale larynx does not appear to be permanently intranarial. The elongated and trough‐shaped epiglottis may function as a tube when placed against the undersurface of the soft palate and, thus, facilitate channeling air from the larynx to the oral cavity. The pointed tip and lateral edges of the epiglottis fit tightly against the undersurface of the soft palate, perhaps functioning as a one‐way valve that lets air out but prevents water from entering. Bubble cloud generation likely involves air passing directly from the larynx into the oral cavity, and then expulsion through the mesh of the baleen plates. A laryngeal–oral connection, however, compromises the anatomical aquatic adaptations that normally protect the respiratory tract. A potential for drowning exists during the critical interval in which the larynx is intraoral and during re‐insertion back to the normal intranarial position. The retention of this risky behavior indicates the importance of bubble clouds in predator avoidance, prey capture, and/or social signaling. Anat Rec, 290:569–580, 2007. © 2007 Wiley‐Liss, Inc.
Effects of ecdysteroid agonist RH‐2485 reveal interactions between ecdysteroids and juvenile hormones in the development of Sesamia nonagrioides
Authors: Eizaguirre Matilde , López Carmen , Schafellner Christa , Sehnal František
Published: May 2007

Larvae of Sesamia nonagrioides developing under long day (LD) conditions pupate in the 5th or 6th instar, whereas under the short day (SD) conditions, they undergo several supernumerary larval molts and are regarded as diapausing. The development in early larval instars occurs in the LD larvae at a moderate and in the SD larvae at a high juvenile hormone (JH) titer; ecdysteroid titer cycles similarly under both conditions. The transformation to pupa is initiated by a burst of ecdysteroids at undetectable JH levels, whereas extra larval molts in the diapausing larvae are associated with moderate JH titer and irregular rises of ecdysteroids. Application of 0.2 ppm RH‐2485 to the diet of the 6th instar larvae promotes hormonal changes supporting metamorphosis in the LD larvae and slightly accelerates larval molts in the diapausing SD larvae. The 0.5‐ and 1‐ppm doses revert these patterns of endocrine regulations to a mode typical for early larval instars. Particularly dramatic is a JH titer increase provoked within 24 h in the LD larvae. After the treatment, both the LD and SD larvae undergo a series of larval molts, suggesting that hormonal programming of the larval development has been stabilized. A few insects receiving 1 ppm RH‐2485, and a high proportion of those fed with 5 ppm RH‐2485, deposit two cuticles within a single apolysis and die. Arch. Insect Biochem. Physiol. 65:74–84, 2007. © 2007 Wiley‐Liss, Inc.
Diversity of detoxification pathways of ingested ecdysteroids among phytophagous insects
Authors: Rharrabe Kacem , Alla Salah , Maria Annick , Sayah Fouad , Lafont René
Published: May 2007

The metabolic pathways of ingested ecdysteroids have been investigated in three insect species, the aphid Myzus persicae and two Lepidoptera, Plodia interpunctella and Ostrinia nubilalis. M. persicae produces mainly a 22‐glucoside conjugate, whereas P. interpunctella eliminates a mixture of 20E and its 3‐oxo and 3‐epi derivatives, both in free form and as conjugates with various fatty acids. O. nubilalis only produces fatty acyl ester conjugates. These data point out the great diversity of detoxification mechanisms used by phytophagous insects in order to overcome the potential harmful effects of ecdysteroids present in their food. Arch. Insect Biochem. Physiol. 65:65–73, 2007. © 2007 Wiley‐Liss, Inc.
Über heterocyclische Siebenringsysteme, XI. Ringschlußreaktionen mit o.o′‐Diamino‐biphenyl
Authors: Ried Walter , Storbeck Werner
Published: May 2007

Die Umsetzung von o.o′‐Diamino‐biphenyl mit Carbonsäuren, Acetessigester und Orthoestern, ferner die thermische Kondensation von o‐Acylamino‐o′‐amino‐biphenyl‐Derivaten wird beschrieben.
Synthese der 2‐Oxo‐3.4‐dimethyl‐penten‐(4)‐säure
Authors: Wieland Theodor , Ismail Roshdy M.
Published: May 2007

Die ungesättigte Ketosäure II konnte aus dem Isopentenylchlorid III über die Grignard‐Verbindung mit Oxalester in 10‐proz. Ausbeute erhalten werden. Ihr Strukturbeweis wurde durch IR‐ und Protonenresonanzspektroskopie geführt. Das Phenythydrazon geht bei der katalytischen Hydrierung in eine einheitliche ninhydrin‐positive Verbindung über, die wohl ein β‐Methyl‐leucin ist.

Die Addition substituierter Cyclopentadiene an Äthylen zu einer Reihe alkylsubstituierter Bicyclo‐[1.2.2]‐heptene, deren wichtigster Vertreter das Santen ist.
Phosphororganische Verbindungen, XXXIV. Cyclopropanderivate aus metallierten Phosphinoxyden und Olefinoxyden
Authors: Hoffmann Leopold Horner, Hellmut , Toscano Vicente G.
Published: May 2007

γ‐Hydroxy‐phosphinoxyde, dargestellt aus metallierten Phosphinoxyden und Olefinoxyden, zerfallen beim Erwärmen in Gegenwart von basen in Cyclopropanderivate und Phosphinsäure, γ‐Hydroxy‐phosphinoxyde liefern mit Thionylchlorid γ‐Chlor‐phosphinoxyde, die metallierbar sind und Cyclopropylphosphinoxyde bilden. Diese spalten bei geeigneter Substitution in Cyclopropanderivate und phosphinsäure auf.
Zum Mechanismus der Cyclooctatetraen‐Synthese nach W. Reppe
Authors: Schrauzer Gerhard N. , Eichler Siegfried
Published: May 2007

Die Bildung von Cyclooctatetraen aus Acetylen wird von Nickel(II)‐Komplexen mit schwachem Ligandenfeld katalysiert. Geschwindigkeitsbestimmender Schritt der Reaktion ist die Lösung koordinativer nickel‐Ligand‐Bindungen im Katalysatormoleköl. Die Bildung von Cyclooctatetraen erfolgt innerhalb von labilen Ni11‐Acetylen‐Komplexen. Inhibitionsversuche machen es wahrscheinlich, daß das NiII‐lon im Übergangszustand von vier Acetylemolekülen umgeben ist, die sich ohne weitere faßbare Zwischenstufe direkt zum Cyclooctatetreaen vereinigen.
Virtual reality exposure in the treatment of panic disorder and agoraphobia: A controlled study
Authors: Botella C. , García‐Palacios A. , Villa H. , Baños R. M. , Quero S. , Alcañiz M. , Riva G.
Published: May 2007

The main goal of this study was to offer data about the efficacy of virtual reality exposure (VRE) in the treatment of panic disorder with or without agoraphobia (PDA). The study was a between‐subject design with three experimental conditions (VRE group, in vivo exposure [IVE] group and waiting‐list [WL] group) and repeated measures (pre‐treatment, post treatment and 12 month follow‐up). The treatment programmes lasted 9 weekly sessions. Thirty‐seven patients meeting DSM‐IV criteria for PDA participated in this study. The improvement achieved using virtual exposure was superior to a WL condition and similar to that achieved using IVE. Our results support the efficacy of VRE in the treatment of PDA at short and long term. The advantages of VRE for the treatment of PDA regarding cost‐benefit issues are described. Copyright © 2007 John Wiley & Sons, Ltd.
What does viewing a pro‐anorexia website do? an experimental examination of website exposure and moderating effects
Authors: Bardone‐Cone Anna M. , Cass Kamila M.
Published: May 2007

Objective:

This study experimentally examined the effects of viewing a pro‐anorexia website.

Method:

Following construction of a prototypic pro‐anorexia website, 235 female undergraduates were randomly assigned to view either the pro‐anorexia website or one of two comparison websites related to female fashion (using average‐sized models) or home décor. Post‐website affect, cognitions, and behavioral expectations were examined along with moderator effects.

Results:

Study participants exposed to the pro‐anorexia website had greater negative affect, lower social self‐esteem, and lower appearance self‐efficacy post‐website than those who viewed a comparison website. Additionally, they perceived themselves as heavier, reported a greater likelihood of exercising and thinking about their weight in the near future, and engaged in more image comparison. Minimal support was found for moderator effects.

Conclusion:

Results provide an empirical basis for concern (expressed by clinicians, researchers, the media) that pro‐anorexia websites are a troubling new form of thin‐ideal exposure that warrants further examination. © 2007 by Wiley Periodicals, Inc.
Clustering technique to reduce chip area and delay for FPGA
Authors: Kobata Masaki , Iida Masahiro , Sueyoshi Toshinori
Published: May 2007

In this paper, we study the requirements for electronic design automation (EDA) tools in deep‐submicron technologies and identify critical factors for programmable logic devices. We also propose a clustering technique for a cluster‐based FPGA to optimize routability of outer cluster nets. In order to reduce the routing resources used in FPGA, this technique uses two evaluation functions. One evaluation function reduces the routing resources in the outer cluster. The second evaluation function utilizes various characteristics of the local routing resources in the inner cluster. Our clustering technique has the unique ability to optimize routing resources concurrently. As a result, the area is decreased by 13.5%, and the delay is reduced by 9.3% as compared to the latest clustering tool in benchmark circuits. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(6): 34–46, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ ecjb.20361
Synthesis and Spectro‐electrochemical Aspects of [RuII(trpy)(pdt)(X)]n+ (trpy = 2,2′:6′,2″‐Terpyridine, pdt = 5,6‐Diphenyl‐3‐pyridyl‐as‐triazine, X = Cl–, CH3CN, NO2–, NO+, NO·) – Electrophilicity of {RuII–NO+} and Photolability of {RuII–NO·}
Authors: Maji Somnath , Chatterjee Chandrani , Mobin Shaikh M. , Lahiri Goutam Kumar
Published: May 2007

Nitrosylruthenium derivatives having NO+ and NO· states have been synthesized in a stepwise manner starting from [RuII(trpy)(pdt)(Cl)](ClO4) {[1](ClO4)} → [RuII(trpy)(pdt)(CH3CN)](ClO4)2 {[2](ClO4)2} → [RuII(trpy)(pdt)(NO2)](ClO4) {[3](ClO4)} → [RuII(trpy)(pdt)(NO+)](ClO4)3 {[4](ClO4)3} → [RuII(trpy)(pdt)(NO·)](ClO4)2 {[4](ClO4)2} [trpy = 2,2′:6′,2″‐terpyridine, pdt = 5,6‐diphenyl‐3‐pyridyl‐as‐triazine]. The molecular identity of [1](ClO4) and [2](ClO4)2 and the subsequent stereoretentive transformation of [1](ClO4) → [2](ClO4)2 have been authenticated by single‐crystal X‐ray structures. Electrochemical and spectral features are investigated as a function of the monodentate ligands (Cl–, CH3CN, NO2–, NO+, NO·). The kinetic and thermodynamic aspects of the reaction of the moderately strong electrophilic {RuII–NO+} center [ν(NO): 1944 cm–1] in [4]3+ with a nucleophile such as OH– have been studied. The nitrosyl species [RuII(trpy)(pdt)(NO+)]3+ ([4]3+) can be selectively reduced to [RuII(trpy)(pdt)(NO·)]2+ ([4]2+) electrochemically as well as chemically by hydrazine hydrate. On exposure to light an acetonitrile solution of [RuII(trpy)(pdt)(NO·)]2+ ([4]2+) undergoes slow photocleavage of the RuII–NO bond over a period of 4 h, resulting in the corresponding solvated species [RuII(trpy)(pdt)(CH3CN)]2+ ([2]2+). The rate of photolability of the RuII–NO bond in [4]2+ has been monitored spectrophotometrically. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)