Renal Artery Denervation for the Management of Hypertension: Current Trends and Future Direction.

Renal artery denervation has re-emerged as a potential therapeutic option for patients with hypertension, especially those resistant to conventional pharmacotherapy. This comprehensive review explores the importance of careful patient selection, procedural techniques, clinical efficacy, safety considerations, and future directions of renal artery denervation in hypertension management. Drawing upon a wide range of available evidence, this review aims to provide a thorough understanding of the procedure and its role in contemporary hypertension treatment paradigms.

Lack of Vesicular Zinc Does Not Affect the Behavioral Phenotype of Polyinosinic:Polycytidylic Acid-Induced Maternal Immune Activation Mice.

Zinc is important in neural and synaptic development and neuronal transmission. Within the brain, zinc transporter 3 (ZnT3) is essential for zinc uptake into vesicles. Loss of vesicular zinc has been shown to produce neurodevelopmental disorder (NDD)-like behavior, such as decreased social interaction and increased anxiety- and repetitive-like behavior.

Binding of l-kynurenine to X. campestris tryptophan 2,3-dioxygenase.

The kynurenine pathway is the major route of tryptophan metabolism. The first step of this pathway is catalysed by one of two heme-dependent dioxygenase enzymes - tryptophan 2,3-dioxygenase (TDO) and indoleamine 2,3-dioxygenase (IDO) - leading initially to the formation of N-formylkynurenine (NFK). In this paper, we present a crystal structure of a bacterial TDO from X.

Examination of Zinc in the Circadian System.

Zinc is a trace element that is essential for a large number of biological and biochemical processes in the body. In the nervous system zinc is packaged into synaptic vesicles by the ZnT3 transporter, and synaptic release of zinc can influence the activity of postsynaptic cells, either directly through its own cognate receptors, or indirectly by modulating activation of receptors for other neurotransmitters. Here, we explore the anatomical and functional aspects of zinc in the circadian system.

Effects of enriched housing on the neuronal morphology of mice that lack zinc transporter 3 (ZnT3) and vesicular zinc.

In the central nervous system, certain neurons store zinc within the synaptic vesicles of their axon terminals. This vesicular zinc can then be released in an activity-dependent fashion as an intercellular signal. The functions of vesicular zinc are not entirely understood, but evidence suggests that it is important for some forms of experience-dependent plasticity in the brain.

Influence of case definition on incidence and outcome of acute coronary syndromes.

Objective: Acute coronary syndromes (ACS) are common, but their incidence and outcome might depend greatly on how data are collected. We compared case ascertainment rates for ACS and myocardial infarction (MI) in a single institution using several different strategies.

Methods: The Hull and East Yorkshire Hospitals serve a population of ∼560 000.

Behavioral characterization of female zinc transporter 3 (ZnT3) knockout mice.

Zinc is an important element in all cells of the body, having structural, enzymatic, and regulatory functions. In some neurons, zinc is loaded into synaptic vesicles by zinc transporter 3 (ZnT3) and released into the synaptic cleft, where it can modulate neuronal function. ZnT3 knockout (KO) mice lack ZnT3 and thus lack synaptic zinc.

Biomarkers of coronary endothelial health: correlation with invasive measures of collateral function, flow and resistance in chronically occluded coronary arteries and the effect of recanalization.

Objectives: In the presence of a chronically occluded coronary artery, the collateral circulation matures by a process of arteriogenesis; however, there is considerable variation between individuals in the functional capacity of that collateral network. This could be explained by differences in endothelial health and function. We aimed to examine the relationship between the functional extent of collateralization and levels of biomarkers that have been shown to relate to endothelial health.

Renal artery sympathetic denervation: observations from the UK experience.

Background: Renal denervation (RDN) may lower blood pressure (BP); however, it is unclear whether medication changes may be confounding results. Furthermore, limited data exist on pattern of ambulatory blood pressure (ABP) response-particularly in those prescribed aldosterone antagonists at the time of RDN.

Methods: We examined all patients treated with RDN for treatment-resistant hypertension in 18 UK centres.

Microvascular dysfunction in the immediate aftermath of chronic total coronary occlusion recanalization.

Objectives: The aim of this study was to compare microvascular resistance under both baseline and hyperemic conditions immediately after percutaneous coronary intervention (PCI) of a chronic total occlusion (CTO) with an unobstructed reference vessel in the same patient

Background: Microvascular dysfunction has been reported to be prevalent immediately after CTO PCI. However, previous studies have not made comparison with a reference vessel. Patients with a CTO may have global microvascular and/or endothelial dysfunction, making comparison with established normal values misleading.

Medical therapy, percutaneous coronary intervention and prognosis in patients with chronic total occlusions.

Objective: There is little published data reporting outcomes for those found to have a chronic total coronary occlusion (CTO) that is electively treated medically versus those treated by percutaneous coronary intervention (PCI). We sought to compare long-term clinical outcomes between patients treated by PCI and elective medical therapy in a consecutive cohort of patients with an identified CTO.

Methods: Patients found to have a CTO on angiography between January 2002 and December 2007 in a single tertiary centre were identified using a dedicated database.

Collateral donor artery physiology and the influence of a chronic total occlusion on fractional flow reserve.

Background: The presence of a concomitant chronic total coronary occlusion (CTO) and a large collateral contribution might alter the fractional flow reserve (FFR) of an interrogated vessel, rendering the FFR unreliable at predicting ischemia should the CTO vessel be revascularized and potentially affecting the decision on optimal revascularization strategy. We tested the hypothesis that donor vessel FFR would significantly change after percutaneous coronary intervention of a concomitant CTO.

Methods And Results: In consecutive patients undergoing percutaneous coronary intervention of a CTO, coronary pressure and flow velocity were measured at baseline and hyperemia in proximal and distal segments of both nontarget vessels, before and after percutaneous coronary intervention.

Differences between community professional and patient perceptions of chronic obstructive pulmonary disease treatment outcomes: a qualitative study.

Aims And Objectives: This study aims to define, compare and order 'assessed needs and defined outcomes' of professional providers of chronic obstructive pulmonary disease services with patients' 'prioritised needs and defined outcomes' and relate these to service provision.

Background: Long-term morbidity and death rates from respiratory diseases in the UK are increasing. Few studies report patient views and perceptions of needs or priorities for respiratory conditions in primary care.

Atherosclerotic disease of the abdominal aorta and its branches: prognostic implications in patients with heart failure.

Aortic atherosclerosis reduces compliance in the systemic circulation and increases peripheral resistance, afterload and left ventricular wall stress. In patients with heart failure, these changes can impair left ventricular systolic function and energy efficiency, which could reduce exercise capacity. Though the interaction and the impact of aortic atherosclerosis on left ventricular function have been investigated, its prognostic implications in patients with heart failure are unclear.

The mechanism of formation of N-formylkynurenine by heme dioxygenases.

Heme dioxygenases catalyze the oxidation of L-tryptophan to N-formylkynurenine (NFK), the first and rate-limiting step in tryptophan catabolism. Although recent progress has been made on early stages in the mechanism, there is currently no experimental data on the mechanism of product (NFK) formation. In this work, we have used mass spectrometry to examine product formation in a number of dioxygenases.

Structure and reaction mechanism in the heme dioxygenases.

As members of the family of heme-dependent enzymes, the heme dioxygenases are differentiated by virtue of their ability to catalyze the oxidation of l-tryptophan to N-formylkynurenine, the first and rate-limiting step in tryptophan catabolism. In the past several years, there have been a number of important developments that have meant that established proposals for the reaction mechanism in the heme dioxygenases have required reassessment. This focused review presents a summary of these recent advances, written from a structural and mechanistic perspective.

Clinical indications for intravascular ultrasound imaging.

Intravascular ultrasound (IVUS) is a catheter-based imaging modality, which provides high resolution cross-sectional images of the coronary arteries. Unlike angiography, which displays only the opacified luminal silhouette, IVUS permits imaging of both the lumen and vessel wall and allows characterization of the type of the plaque. Although IVUS provides accurate quantitative and qualitative information regarding the lumen and outer vessel wall, it is not routinely used during coronary angiography or in angioplasty procedures because the risk to benefit ratio (additional expense, procedural time, certain degree of risk, and complication versus improvement in the outcome) does not justify routine utilization.

Probing the ternary complexes of indoleamine and tryptophan 2,3-dioxygenases by cryoreduction EPR and ENDOR spectroscopy.

We have applied cryoreduction/EPR/ENDOR techniques to characterize the active-site structure of the ferrous-oxy complexes of human (hIDO) and Shewanella oneidensis (sIDO) indoleamine 2,3-dioxygenases, Xanthomonas campestris (XcTDO) tryptophan 2,3-dioxygenase, and the H55S variant of XcTDO in the absence and in the presence of the substrate L-Trp and a substrate analogue, L-Me-Trp. The results reveal the presence of multiple conformations of the binary ferrous-oxy species of the IDOs. In more populated conformers, most likely a water molecule is within hydrogen-bonding distance of the bound ligand, which favors protonation of a cryogenerated ferric peroxy species at 77 K.

Echocardiographic identification of ventricular septal rupture caused by acute stent thrombosis.

Coronary stenting is an increasingly common procedure. Complications are rare. However, when they do occur, they often require urgent invasive treatment.

Reassessment of the reaction mechanism in the heme dioxygenases.

Indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO) are heme enzymes that catalyze the O(2)-dependent oxidation of L-tryptophan to N-formyl-kynurenine. Previous proposals for the mechanism of this reaction have suggested that deprotonation of the indole NH group, either by an active-site base or by oxygen bound to the heme iron, as the initial step. In this work, we have examined the activity of 1-Me-L-Trp with three different heme dioxygenases and their site-directed variants.