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Clinical Hemorheology and... 2023Cannabinoids play critical roles in human pathophysiology through the cannabinoid (CB) receptors and non-CB receptors on variety of cells, tissues, and organs.... (Review)
Review
Cannabinoids play critical roles in human pathophysiology through the cannabinoid (CB) receptors and non-CB receptors on variety of cells, tissues, and organs. Microvasculature with the inside bloodstream containing the plasmatic and cellular components exerts multiple functions in maintaining tissue and organ physiology through microcirculation. This review focusses on the impact of cannabinoids on the microvasculature, including mechanisms mediated by both CB receptor-related pathways and CB receptor-independent pathways.
Topics: Humans; Cannabinoids; Microvessels; Receptor, Cannabinoid, CB2; Receptors, Cannabinoid; Microcirculation
PubMed: 36591655
DOI: 10.3233/CH-221677 -
Nature Reviews. Nephrology Jul 2022
Topics: Humans; Kidney; Microcirculation; Renal Circulation
PubMed: 35668234
DOI: 10.1038/s41581-022-00595-8 -
Microcirculation (New York, N.Y. : 1994) Jul 2017A challenge for basic and applied microvascular research is the lack of ex vivo experimental platforms that mimic the structural and functional complexity that is...
A challenge for basic and applied microvascular research is the lack of ex vivo experimental platforms that mimic the structural and functional complexity that is inherent to the microcirculation in living organisms. This Special Topic Issue highlights the emergence of microfluidic-based approaches as tools for recapitulating physiologically relevant network architectures and hemodynamics to study biochemical and biomechanical mechanisms of microvascular function and adaptation. This collection of review and original research articles showcases the value of microfluidics in bridging the gap between in vivo and in vitro model systems by demonstrating the utility of this technology for investigating microvascular dynamics spanning angiogenesis to blood cell rheology and for preclinical evaluation of therapeutic strategies that target the microcirculation.
Topics: Humans; Microcirculation; Microfluidics
PubMed: 28470950
DOI: 10.1111/micc.12377 -
Journal of Endocrinological... Sep 2017Diabetic retinopathy (DR) is the leading cause of visual impairment and preventable blindness and represents a significant socioeconomic cost for healthcare systems... (Review)
Review
Diabetic retinopathy (DR) is the leading cause of visual impairment and preventable blindness and represents a significant socioeconomic cost for healthcare systems worldwide. In early stages of DR the only therapeutic strategy that physicians can offer is a tight control of the risk factors for DR (mainly blood glucose and blood pressure). The currently available treatments for DR are applicable only at advanced stages of the disease and are associated with significant adverse effects. Therefore, new treatments for the early stages of DR are needed. However, in early stages of DR invasive treatments such as intravitreal injections are too aggressive, and topical treatment seems to be an emerging route. In the present review, therapeutic strategies based on the main pathogenic mechanisms involved in the development of DR are reviewed. The main gap in the clinical setting is the treatment of early stages of DR and, therefore, this review emphasizes in this issue by giving an overview of potential druggable targets. By understanding of disease-specific pathogenic mechanisms, biological heterogeneity and progression patterns in early and advanced DR a more personalised approach to patient treatment will be implemented.
Topics: Animals; Blood Glucose; Blood Pressure; Diabetic Retinopathy; Humans; Hypoglycemic Agents; Microcirculation; Neurodegenerative Diseases; Risk Factors
PubMed: 28357783
DOI: 10.1007/s40618-017-0648-4 -
Critical Care (London, England) Mar 2018This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2018. Other selected articles can be found online at... (Review)
Review
This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2018. Other selected articles can be found online at https://www.biomedcentral.com/collections/annualupdate2018 . Further information about the Annual Update in Intensive Care and Emergency Medicine is available from http://www.springer.com/series/8901 .
Topics: Administration, Intravenous; Decision Support Techniques; Fluid Therapy; Humans; Intensive Care Units; Microcirculation
PubMed: 29558989
DOI: 10.1186/s13054-018-1993-1 -
Perfusion Jan 2018Cardiac arrest represents a leading cause of mortality and morbidity in developed countries. Extracorporeal cardiopulmonary resuscitation (ECPR) increases the chances... (Review)
Review
Cardiac arrest represents a leading cause of mortality and morbidity in developed countries. Extracorporeal cardiopulmonary resuscitation (ECPR) increases the chances for a beneficial outcome in victims of refractory cardiac arrest. However, ECPR and post-cardiac arrest care are affected by high mortality rates due to multi-organ failure syndrome, which is closely related to microcirculatory disorders. Therefore, microcirculation represents a key target for therapeutic interventions in post-cardiac arrest patients. However, the evaluation of tissue microcirculatory perfusion is still demanding to perform. Novel videomicroscopic technologies (Orthogonal polarization spectral, Sidestream dark field and Incident dark field imaging) might offer a promising way to perform bedside microcirculatory assessment and therapy monitoring. This review aims to summarise the recent body of knowledge on videomicroscopic imaging in a cardiac arrest setting and to discuss the impact of extracorporeal reperfusion and other therapeutic modalities on microcirculation.
Topics: Diagnostic Imaging; Heart Arrest; Humans; Microcirculation; Perfusion
PubMed: 28812428
DOI: 10.1177/0267659117723455 -
Einstein (Sao Paulo, Brazil) 2015The early recognition and treatment of severe sepsis and septic shock is the key to a successful outcome. The longer the delay in starting treatment, the worse the... (Review)
Review
The early recognition and treatment of severe sepsis and septic shock is the key to a successful outcome. The longer the delay in starting treatment, the worse the prognosis due to persistent tissue hypoperfusion and consequent development and worsening of organ dysfunction. One of the main mechanisms responsible for the development of cellular dysfunction is tissue hypoxia. The adjustments necessary for adequate tissue blood flow and therefore of oxygen supply to metabolic demand according to the assessment of the cardiac index and oxygen extraction rate should be performed during resuscitation period, especially in high complexity patients. New technologies, easily handled at the bedside, and new studies that directly assess the impact of macro-hemodynamic parameter optimization on microcirculation and in the clinical outcome of septic patients, are needed.
Topics: Critical Care; Early Diagnosis; Hemodynamics; Humans; Lactic Acid; Microcirculation; Oxygen; Sepsis; Shock, Septic
PubMed: 26313438
DOI: 10.1590/S1679-45082015RW3148 -
Critical Care Medicine Jul 2023This observational study was conducted to investigate capillary refill time (CRT) during the early phase of ICU admission in relationship with microvascular flow... (Observational Study)
Observational Study
OBJECTIVES
This observational study was conducted to investigate capillary refill time (CRT) during the early phase of ICU admission in relationship with microvascular flow alteration and outcome in critically ill patients.
DESIGN
Prospective, observational, pilot study.
SETTING
ICU in a university hospital.
PATIENTS
Two hundred eighty-two critically ill adult patients admitted to the ICU.
INTERVENTIONS
None.
MEASUREMENTS AND MAIN RESULTS
All patients underwent simultaneous measurements by CRT and sidestream dark field imaging within 24 hours of ICU admission. Other clinical data such as demographic characteristics, hemodynamics, laboratory values, treatment, and physiologic parameters were also included simultaneously. Microcirculatory measurements were performed at 10.2 ± 5.7 hours after ICU admission. Of the 282 included patients, 106 (37.6%) were female, the median (interquartile range) age was 63 years (53-74 yr), and the median Sequential Organ Failure Assessment (SOFA) score was 5 (2-7). The primary finding was the association between CRT and simultaneous the condition of peripheral circulation (microvascular flow index [MFI]: r = -0.4430, p < 0.001; proportion of perfused vessels: r = -0.3708, p < 0.001; heterogeneity index: r = 0.4378, p < 0.001; perfused vessel density: r = -0.1835, p = 0.0020; except total vessel density: p = 0.9641; and De Backer score: p = 0.5202) in critically ill patients. In addition, this relationship was also maintained in subgroups. Microcirculatory flow abnormalities, 28-day mortality, and SOFA score appeared to be more severe for increasing CRT. In a multivariable analysis, prolonged CRT was independently associated with microvascular flow abnormalities (MFI < 2.6; odds ratio [OR], 1.608; 95% CI, 2.1-10.2; p < 0.001). Similarly, multivariable analysis identified CRT as an independent predictor of 28-day mortality (OR, 1.296; 95% CI, 1.078-1.558; p = 0.006).
CONCLUSIONS
In our ICU population, a single-spot prolonged CRT was independently associated with abnormal microcirculation and increased mortality.
Topics: Adult; Humans; Female; Middle Aged; Male; Microcirculation; Prospective Studies; Critical Illness; Pilot Projects; Mouth Floor; Hemodynamics; Intensive Care Units
PubMed: 36942969
DOI: 10.1097/CCM.0000000000005851 -
Acta Anaesthesiologica Scandinavica Nov 2015Severe sepsis is defined by organ failure, often of the kidneys, heart, and brain. It has been proposed that inadequate delivery of oxygen, or insufficient extraction of... (Review)
Review
Severe sepsis is defined by organ failure, often of the kidneys, heart, and brain. It has been proposed that inadequate delivery of oxygen, or insufficient extraction of oxygen in tissue, may explain organ failure. Despite adequate maintenance of systemic oxygen delivery in septic patients, their morbidity and mortality remain high. The assumption that tissue oxygenation can be preserved by maintaining its blood supply follows from physiological models that only apply to tissue with uniformly perfused capillaries. In sepsis, the microcirculation is profoundly disturbed, and the blood supply of individual organs may therefore no longer reflect their access to oxygen. We review how capillary flow patterns affect oxygen extraction efficacy in tissue, and how the regulation of tissue blood flow must be adjusted to meet the metabolic needs of the tissue as capillary flows become disturbed as observed in critical illness. Using the brain, heart, and kidney as examples, we discuss whether disturbed capillary flow patterns might explain the apparent mismatch between organ blood flow and organ function in sepsis. Finally, we discuss diagnostic means of detecting capillary flow disturbance in animal models and in critically ill patients, and address therapeutic strategies that might improve tissue oxygenation by modifying capillary flow patterns.
Topics: Capillaries; Critical Illness; Humans; Microcirculation; Oxygen; Regional Blood Flow; Sepsis
PubMed: 26149711
DOI: 10.1111/aas.12581 -
European Heart Journal Dec 2015
Topics: Collateral Circulation; Coronary Circulation; Heart Diseases; Humans; Microcirculation; Plaque, Atherosclerotic
PubMed: 26628568
DOI: 10.1093/eurheartj/ehv629