Development of respiratory control instability in heart failure: a novel approach to dissect the pathophysiological mechanisms.

Observational data suggest that periodic breathing is more common in subjects with low F(ETCO(2)), high apnoeic thresholds or high chemoreflex sensitivity. It is, however, difficult to determine the individual effect of each variable because they are intrinsically related. To distinguish the effect of isolated changes in chemoreflex sensitivity, mean F(ETCO(2)) and apnoeic threshold, we employed a modelling approach to break their obligatory in vivo interrelationship.

The effect of machine perfusion on the arteries of porcine kidneys.

Objectives: Machine perfusion is an excellent method of assessing the viability of a kidney graft and can also potentially improve the quality of an equivocal kidney. Several authors have expressed concerns that machine perfusion can potentially damage the vessels of the kidney but until now, no studies have been performed to clarify this issue. We aimed to examine the effect of machine perfusion on the renal arteries of porcine kidneys.

Optimization of the arterial input function for myocardial perfusion cardiovascular magnetic resonance.

Purpose: To determine how injection rate, cardiac function, and breathhold influence the arterial input function (AIF), in order to optimize the AIF in the clinical setting for quantitative myocardial perfusion cardiovascular magnetic resonance (CMR).

Materials And Methods: Gd (0.1 mmol/kg) bolus was injected at 3, 5, or 7 mL/second in 35 patients.

Electromechanical left ventricular resynchronisation by coronary artery bypass surgery.

Objective: In patients with coronary artery disease (CAD), the normal electromechanical response to dobutamine stress is deranged: QRS duration lengthens rather than shortens, left ventricular asynchrony develops, post-ejection shortening appears, and total isovolumic time (the time in the cardiac cycle when the ventricle is neither ejecting nor filling) increases rather than falls, all of which blunt the normal rise in cardiac output. We aimed to study the effect of revascularisation on these stress-induced electromechanical abnormalities and their effect on peak cardiac output after coronary artery bypass grafting (CABG).

Method: 20 unselected patients were studied before and after CABG.

Mapping of the immunodominant T cell epitopes of the protein topoisomerase I.

Objectives: To identify the immunodominant T cell epitopes of the topoisomerase I protein in patients with systemic sclerosis (SSc) and control subjects, using computational analysis software (TEPITOPE) and T cell proliferation assays.

Methods: Six oligopeptides, predicted by TEPITOPE software as potential topoisomerase protein epitopes, were used to perform T cell proliferation assays in 21 patients with SSc and 15 healthy controls.

Results: A positive response to at least one of the peptides was seen in 10/21 patients and 7/15 healthy controls.

Clinical results with direct thrombin inhibitors.

Direct thrombin inhibitors inactivate thrombin without the need for antithrombin and some inactivate not only thrombin but also fibrin-bound thrombin. Hirudin has been shown to be more effective than low-dose unfractionated heparin and low molecular weight heparin for the prevention of deep vein thrombosis in high-risk orthopaedic patients. Major studies are assessing the value of direct thrombin inhibitors in patients with acute coronary syndromes.

Limitation of cardiac output by total isovolumic time during pharmacologic stress in patients with dilated cardiomyopathy: activation-mediated effects of left bundle branch block and coronary artery disease.

Objectives: We sought to separate the effects of associated left bundle branch block (LBBB) and coronary artery disease (CAD) on peak cardiac output (CO) during dobutamine stress in patients with dilated cardiomyopathy (DCM).

Background: The mechanisms limiting CO during stress in patients with DCM are unclear. Both LBBB and CAD may do so by prolonging the total isovolumic time (t-IVT).

Morphologic spectrum of estrogen receptor-negative breast carcinoma.

Context: Estrogen receptor (ER)-negative breast carcinomas are a heterogeneous group of breast cancers that are generally thought to be aggressive.

Objective: To determine the morphologic and immunohistochemical spectrum of a consecutive series of ER-negative breast carcinomas, in an attempt to understand the pathogenesis and behavior of these lesions.

Design: Seventy-four consecutive cases of ER-negative invasive carcinomas were studied.

Super-Charged Porphyrazines: Synthesis and Physical Properties of Octacationic Tetraazaporphyrins.

We report the synthesis of octacationic macrocycles based on the porphyrazine (tetraazaporphyrin) core. The first stage is the synthesis of Mg(II) 2,3,7,8,12,13,17,18-octakis(4-pyridyl)porphyrazine, [Mgpz(pyr)(8)], and the parent [H(2)pz(pyr)(8)]. Both compounds are freely soluble in aqueous acid due to protonation of the pyridyl groups but with concomitant loss of Mg(2+) by the latter.

Peripheral Palladium(II) and Platinum(II) Complexes of Bis(dimethylamino)porphyrazine.

The unsymmetrical porphyrazine (tetraazaporphyrin) bearing a single peripheral bis(dimethylamino) functionality, Mg[pz(NMe(2))(2)(Pr)(6)], was prepared by base-catalyzed cross condensation of dipropyl maleonitrile (in excess) with dimethylamino maleonitrile. The freebase (2H[pz(NMe(2))(2)(Pr)(6)]) and centrally metalated forms (M[pz(NMe(2))(2)(Pr)(6)]; M = Ni(II), Cu(II), Mn(III)) were prepared by treatment of Mg[pz(NMe(2))(2)(Pr)(6)] with trifluoroacetic acid and then the appropriate metal salt. PdCl(2) and PtCl(2) were coordinated to the peripheral bis(dimethylamino) chelates, yielding the bimetallic complexes, M[pz(NMe(2))(2)(Pr)(6)]M'Cl(2) (M = Ni, Cu; M' = Pd, Pt).

Acute respiratory distress syndrome secondary to cardiopulmonary bypass: do compromised plasma iron-binding anti-oxidant protection and thiol levels influence outcome?

Objectives: Cardiopulmonary bypass (CPB) surgery is often associated with mild lung injury and in some patients leads to acute lung injury and acute respiratory distress syndrome (ARDS). Aberrant plasma iron chemistry (increased iron loading of transferrin and/or the presence of redox-active low molecular mass iron) and increased plasma thiol levels are features of this type of surgery and represent a potential pro-oxidant risk for oxidative damage. Oxidative damage is a feature of ARDS, and we hypothesized that pro-oxidant forces may contribute to the onset and progression of ARDS.

Five day moxifloxacin therapy compared with 7 day clarithromycin therapy for the treatment of acute exacerbations of chronic bronchitis.

In this multinational, randomized, double-blind study, the efficacy and safety of a 5 day course of moxifloxacin 400 mg orally od was compared with that of a 7 day course of clarithromycin 500 mg orally bd. in 750 patients with acute exacerbations of chronic bronchitis, characterized by at least two of the symptoms: sputum purulence, increased sputum volume or increased dyspnoea. Seven days after the end of therapy, clinical cure was achieved for 89% (287 of 322) of efficacy-evaluable patients in the moxifloxacin group and 88% (289 of 327) of patients in the clarithromycin group (95% CI, -3.

Administration of albumin to patients with sepsis syndrome: a possible beneficial role in plasma thiol repletion.

1. Albumin is often administered intravenously to critically ill patients as a volume expander, to combat hypoalbuminaemia, and to decrease hyperbilirubinaemia. There is, however, an ongoing debate concerning the therapeutic benefit of the former which is an expensive form of treatment.

Diheteroarylmethanes. 6.(1) Probing the Electron-Withdrawing Rank of Heteroaryl Groups by Conformational Studies of Push-Pull Ethylenes. Isolation of NH-Enamine Tautomers of alpha,alpha-Diheteroarylacetaldehydes (Heteroaryl = 2-Benzoxazolyl, 2-Benzothiazolyl).

Enamines and enol ethers substituted in the beta position by the 2-benzoxazolyl and 2-benzothiazolyl group have been obtained by condensing dimethylformamide dimethyl acetal and ethyl orthoformate, respectively, with bis(2-benzoxazolyl)methane and bis(2-benzothiazolyl)methane. A dynamic NMR and semiempirical (PM3) investigation on rotational energy barriers has been carried out in order to rank the electron-withdrawing capacity of the heterocyclic rings. The NMR-based evaluation of the energy barriers corresponding to the rotation along the enaminic double bond has shown that the pi-electron-withdrawing power of benzothiazole is larger than that of benzoxazole, in full accord with previously obtained charge demand values based on (13)C and (15)N pi-charge/shift relationships.

Is the relationship between angiogenesis and metastasis in breast cancer real?

The suggested link between angiogenesis in breast cancer and metastasis remains unsubstantiated. We tested this relationship in primary breast carcinomas from 37 patients with a median follow-up 9.5 years (Cohort 1) and 50 patients with a median follow-up of 1.