Microvascular research
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Microvascular research · Jul 2018
Comparative Study Observational StudyAlterations of conjunctival glycocalyx and microcirculation in non-septic critically ill patients.
As of now the relationship between glycocalyx degradation and microcirculatory perfusion abnormalities in non-septic critical ill patients is unclear. In addition, conjunctival sidestream dark field-imaging for the purpose of glycocalyx thickness estimation has never been performed. We aimed to investigate whether changes in glycocalyx thickness in non-septic patients are associated with microcirculatory alterations in conjunctival and sublingual mucosa. ⋯ We detected a weak correlation between syndecan-1 and sublingual PBR but no correlations between global glycocalyx damage and conjuctival glycocalyx thickness. We found significantly lower perfused vessel density (PVD) of small vessels in sublingual mucosa in patients after cardiac surgery in comparison with healthy subjects. In neuro-critical, but not cardiac surgery patients conjunctival TVD and PVD of small vessels were found to be significantly lower in comparison with controls.
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Microvascular research · Jul 2018
Comparative StudyNear-infrared spectroscopy assessment of microvasculature detects difference in lower limb vascular responsiveness in obese compared to lean individuals.
Microvascular dysfunction is an early complication in obesity-related cardiovascular disease (CVD) that can lead to changes in hemodynamic function and endothelial cell expression throughout the vasculature that is vessel specific. This study aimed to evaluate whether the near-infrared spectroscopy (NIRS) combined with a vascular occlusion (VOT) assessment was capable of detecting differences in vascular responsiveness within the microvasculature of the lower limb between lean and obese individuals. ⋯ This study demonstrated differences in vascular responses within the microvasculature of the lower limb between lean and obese individuals.
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Microvascular research · May 2018
Numerical modeling of fluid and oxygen exchanges through microcirculation for the assessment of microcirculation alterations caused by type 2 diabetes.
Type 2 diabetes mellitus (DM2) is frequently accompanied by microcirculation complications, including structural and functional alterations, which may have serious effects on substance exchanges between blood and interstitial tissue and the health of organs. In this paper, we aim to study the influence of microcirculation alterations in DM2 patients on fluid and oxygen exchanges through a model analysis. A fluid flow and oxygen transport model were developed by considering the interplay between blood in capillary network and interstitial tissue. ⋯ Simulated results show that the impaired connectivity of the network could result in poor robustness in maintaining blood flow and perfused surface; under high fluid permeability conditions of capillary walls, the pressure gradient was much larger around the capillary bed, and this alteration led to a saturation level of the interstitial pressure when lymphatic flow drainage can't work effectively; the variations in network connectivity and permeability of capillary wall also had unfavorable influence on oxygen distributions in interstitial tissue. In addition, when the oxygen releasing capacity of hemoglobin was confined by glycosylated hemoglobin (HbA1) in the case of diabetes, the plasma could not be complemented with adequate oxygen and thus the hypoxic tissue range will be extended. This study illustrates that when microcirculation disturbances, including the structure of capillary network, the wall osmosis property and the capacity of blood binding oxygen occur in DM2, some negative impacts are raised on microvascular hemodynamics and metabolism circumstance of interstitial tissue.
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Microvascular research · Jan 2018
GTS-21 reduces microvascular permeability during experimental endotoxemia.
No effective pharmacological therapy is currently available to attenuate tissue edema formation due to increased microvascular permeability in sepsis. Cholinergic mediators have been demonstrated to exert anti-inflammatory effects via the α7 nicotinic acetylcholine receptor (α7nAChR) during inflammation. GTS-21, a partial α7nAChR agonist, is an appealing therapeutic substance for sepsis-induced microvascular inflammation due to its demonstrated cholinergic anti-inflammatory properties and its favorable safety profile in clinical trials. This study evaluated the effect of GTS-21 on microvascular permeability and leukocyte adhesion during experimental endotoxemia. ⋯ GTS-21 has a protective effect on microvascular barrier function during endotoxemia. Considering its anti-inflammatory efficacy and safety profile, its clinical use might prove beneficial for the treatment of capillary leakage in sepsis therapy.
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Microvascular research · Nov 2017
Nailfold capillaroscopic changes in patients with idiopathic pulmonary arterial hypertension and systemic sclerosis-related pulmonary arterial hypertension.
Pulmonary arterial hypertension (PAH) represents one of the main clinical expressions of the vascular changes in systemic sclerosis (SSc). Lung microvascular changes can play a role in the pathogenesis of idiopathic PAH (IPAH) also. The aim of this study is to investigate the presence of capillaroscopic abnormalities in patients with IPAH and to evaluate the differences in capillary nailfold changes between patients with IPAH and patients with SSc with and without PAH.