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Wounds : a Compendium of Clinical... May 2024Full-thickness skin defects often are managed with split-thickness skin grafting. The wound healing process, including formation of new vessels during the healing of...
BACKGROUND
Full-thickness skin defects often are managed with split-thickness skin grafting. The wound healing process, including formation of new vessels during the healing of skin grafts, is complex.
OBJECTIVE
To evaluate the microcirculatory changes in the treated tissue after skin grafting to analyze perfusion dynamics during the wound healing process.
MATERIALS AND METHODS
Fourteen full-thickness skin defects were created on the back of 14 adult male Lewis rats. All wounds were treated with autologous split-thickness skin grafts. The perfusion dynamics were assessed for 84 days with an O2C device that combines a laser light to determine blood flow and white light to determine postcapillary SO2 and the rHb.
RESULTS
Blood flow increased for 50 days after grafting. SO2 decreased in superficial skin layers (depth of 2 mm) and increased in deep skin layers (depth of 8 mm) during the entire observation period. The rHb increased until day 10 in superficial layers and until day 20 in deep tissue layers.
CONCLUSION
The microcirculatory changes reflect the different phases of wound healing. Long after the skin transplants were macroscopically healed, alterations in microcirculation were still detected. These alterations were caused by the long-lasting changes in tissue metabolism due to the formation, conversion, and degradation of the dermal matrix and vessels during wound healing and scar formation.
Topics: Animals; Wound Healing; Microcirculation; Skin Transplantation; Rats; Male; Rats, Inbred Lew; Skin; Disease Models, Animal
PubMed: 38861214
DOI: 10.25270/wnds/23112 -
Scientific Reports Jun 2024
PubMed: 38858541
DOI: 10.1038/s41598-024-64285-0 -
Biochimie Jun 2024Uropathogenic strains of E. coli (UPEC) is a leading cause of sepsis, deploying multiple virulence factors to evade host immune responses. Notably, alpha-hemolysin...
Uropathogenic strains of E. coli (UPEC) is a leading cause of sepsis, deploying multiple virulence factors to evade host immune responses. Notably, alpha-hemolysin (HlyA) produced by UPEC is implicated in septic symptoms associated with bacteremia, correlating with thrombocytopenia, a critical indicator of organ dysfunction and a predictor of poorer patient prognosis. This study meticulously explores the impact of sublytic concentrations of HlyA on platelets. Findings reveal that HlyA triggers an increase in intracellular calcium, activating calpain and exposing phosphatidylserine to the cell surface, as validated by flow cytometric experiments. Electron microscopy reveals a distinctive balloon-like shape in HlyA-treated platelets, indicative of a procoagulant state. The toxin induces the release of procoagulant extracellular vesicles and the secretion of alpha and dense granules. Overall, the results point to HlyA inducing a necrotic-like procoagulant state in platelets. The effects of sublytic concentrations of HlyA on both erythrocytes and platelets could have a potential impact on capillary microcirculation. Targeting HlyA emerges as a viable therapeutic strategy to mitigate the adverse effects of UPEC infections, especially in South American countries where these infections are endemic, underscoring its significance as a potential therapeutic target.
PubMed: 38857695
DOI: 10.1016/j.biochi.2024.06.001 -
IEEE Transactions on Medical Imaging Jun 2024Glomeruli are the filtration units of the kidney and their function relies heavily on their microcirculation. Despite its obvious diagnostic importance, an accurate...
Glomeruli are the filtration units of the kidney and their function relies heavily on their microcirculation. Despite its obvious diagnostic importance, an accurate estimation of blood flow in the capillary bundle within glomeruli defies the resolution of conventional imaging modalities. Ultrasound Localization Microscopy (ULM) has demonstrated its ability to image in-vivo deep organs in the body. Recently, the concept of sensing ULM or sULM was introduced to classify individual microbubble behavior based on the expected physiological conditions at the micrometric scale. In the kidney of both rats and humans, it revealed glomerular structures in 2D but was severely limited by planar projection. In this work, we aim to extend sULM in 3D to image the whole organ and in order to perform an accurate characterization of the entire kidney structure. The extension of sULM into the 3D domain allows better localization and more robust tracking. The 3D metrics of velocity and pathway angular shift made glomerular mask possible. This approach facilitated the quantification of glomerular physiological parameter such as an interior traveled distance of approximately 7.5 ± 0.6 microns within the glomerulus. This study introduces a technique that characterize the kidney physiology which can serve as a method to facilite pathology assessment. Furthermore, its potential for clinical relevance could serve as a bridge between research and practical application, leading to innovative diagnostics and improved patient care..
PubMed: 38857150
DOI: 10.1109/TMI.2024.3411669 -
World Journal of Emergency Medicine 2024This study aims to explore whether Xuebijing (XBJ) can improve intestinal microcirculation dysfunction in sepsis and its mechanism.
BACKGROUND
This study aims to explore whether Xuebijing (XBJ) can improve intestinal microcirculation dysfunction in sepsis and its mechanism.
METHODS
A rat model of sepsis was established by cecal ligation and puncture (CLP). A total of 30 male SD rats were divided into four groups: sham group, CLP group, XBJ + axitinib group, and XBJ group. XBJ was intraperitoneally injected 2 h before CLP. Hemodynamic data (blood pressure and heart rate) were recorded. The intestinal microcirculation data of the rats were analyzed via microcirculation imaging. Enzyme-linked immunosorbent assay (ELISA) kits were used to detect the serum levels of interleukin-6 (IL-6), C-reactive protein (CRP), and tumor necrosis factor-α (TNF-α) in the rats. Histological analysis and transmission electron microscopy were used to analyze the injury of small intestinal microvascular endothelial cells and small intestinal mucosa in rats. The expression of vascular endothelial growth factor A (VEGF-A), phosphoinositide 3-kinase (PI3K), phosphorylated PI3K (p-PI3K), protein kinase B (Akt), and phosphorylated Akt (p-Akt) in the small intestine was analyzed via Western blotting.
RESULTS
XBJ improved intestinal microcirculation dysfunction in septic rats, alleviated the injury of small intestinal microvascular endothelial cells and small intestinal mucosa, and reduced the systemic inflammatory response. Moreover, XBJ upregulated the expression of VEGF-A, p-PI3K/total PI3K, and p-Akt/total Akt in the rat small intestine.
CONCLUSION
XBJ may improve intestinal microcirculation dysfunction in septic rats possibly through the VEGF-A/PI3K/Akt signaling pathway.
PubMed: 38855370
DOI: 10.5847/wjem.j.1920-8642.2024.035 -
The Journal of International Medical... Jun 2024Treatment of lower limb ischemia in patients with diabetes is challenging because of the location of the ulcers and the complexity of their pathogenesis. Carbon dioxide...
Use of carbon dioxide fractional laser in the management of lower limb ischemia in patients with diabetes: a case report : CO fractional laser in the treatment of diabetic foot.
Treatment of lower limb ischemia in patients with diabetes is challenging because of the location of the ulcers and the complexity of their pathogenesis. Carbon dioxide fractional laser (COFL) therapy in conjunction with tibial periosteum distraction could become a substitute for conventional methods. We herein describe a patient diagnosed with ischemic diabetic foot with a complex ulcer in the upper third of the tibia. Laser irradiation (Deep FX mode with 30 mJ of energy and 10% density) was applied to the entire region of skin below the knee after surface anesthesia, and this treatment was performed twice a week until the ulcer healed. Computed tomography angiography showed successful establishment of a blood supply to the back of the right foot after treatment. Skin grafting was successfully performed, with only a few wounds remaining on the foot 8 months after treatment. The pain score was significantly decreased at the last follow-up. No complications occurred. This case report provides guidance for the performance of COFL, a fast, easy, accurate treatment in patients with diabetes. COFL can target lower limb arterial occlusive disease accompanied by refractory ulcers, addressing the underlying vascular occlusion and dysfunction as well as promoting microcirculation and wound healing.
Topics: Humans; Diabetic Foot; Lasers, Gas; Ischemia; Male; Lower Extremity; Aged; Middle Aged; Wound Healing; Treatment Outcome
PubMed: 38853406
DOI: 10.1177/03000605241253759 -
Contact Lens & Anterior Eye : the... Jun 2024To explore the changes in microcirculation and microvasculature of the bulbar conjunctiva during the short-term wearing of the scleral lenses (ScCL). And investigate the...
OBJECTIVE
To explore the changes in microcirculation and microvasculature of the bulbar conjunctiva during the short-term wearing of the scleral lenses (ScCL). And investigate the factors affecting the microcirculation and microvasculature of the bulbar conjunctiva.
METHODS
In this prospective cross-sectional study, functional slit lamp biomicroscopy (FSLB) was used to image the ocular surface microcirculation and microvascular images at two different sites (under the area of ScCL and outside of the area of ScCL) before (baseline) and during the wearing of ScCL at 0 h, 1 h, 2 h and 3 h. Anterior segment optical coherence tomography (AS-OCT) (RTVue, Optovue Inc, USA) was also used to image central post-lens tear film (PoLTF) and the morphology changes of the conjunctiva under the landing zone at the same time period. The semi-automatic quantification of microcirculation and microvasculature including vessel density (D), vessel diameter (D), axial blood flow velocity (Va) and blood flow volume (Q). And the morphological changes of conjunctiva and PoLTF fogging grading were evaluated manually. The changes in the microcirculation and microvasculature of the ocular surface, PoLTF fogging grade and conjunctival morphology were compared before and during the ScCL wearing at different time periods, and the relationship between them was analyzed.
RESULTS
Nineteen eyes (11 right eyes, 8 left eyes) were analyzed in this study. Outside of the area of ScCL, the D before wearing lenses was less than that at 0 h (P = 0.041). The Q at baseline was greater than that after 1 h ScCL wearing (P = 0.026). Under the area of the ScCL, the Q at 1 h was less than that at baseline and 3 h. During the ScCL wearing, statistically significant conjunctival morphology changes were found among different time stages (baseline (0 μm), 0 h (113.18 μm), 2 h (138.97 μm), 3 h (143.83 μm) (all P <0.05). Outside the area of the ScCL, the morphology changes of the conjunctiva were negatively correlated with the changes of Va (P<0.001,r = -0.471) and Q (P = 0.003,r = -0.348),but positively correlated with the D (P = 0.001,r = 0.386). Under the area of ScCL, the morphology changes of the conjunctiva were negatively correlated with the Q (P = 0.012, r = -0.291). The fogging grade was positively correlated with the Q under the area of the ScCL (P = 0.005, r = 0.331).
CONCLUSIONS
The microcirculation and microvasculature of the ocular surface and conjunctival morphology were changed after wearing ScCL in wearers, which indicated that the microvascular responses happened in the ScCL wearers and the severity of microvascular responses of the ocular surface related to the morphology changes of the conjunctiva. The quantification methods and findings in this study provide clues for the safety of ScCL wearing and may supervise the health of the wearer's ocular surface.
PubMed: 38851944
DOI: 10.1016/j.clae.2024.102159 -
American Journal of Cardiovascular... Jun 2024The clinical advantage of alprostadil [prostaglandin E1 (PGE1)] in the treatment of microcirculatory disturbances (defined as no-reflow or slow-flow) in acute...
OBJECTIVE
The clinical advantage of alprostadil [prostaglandin E1 (PGE1)] in the treatment of microcirculatory disturbances (defined as no-reflow or slow-flow) in acute percutaneous coronary intervention (PCI) is still disputed. The purpose of our study was to review the efficacy of PGE1 supplements in patients with acute myocardial infarction (AMI) who had urgent PCI.
DESIGN
This study was a meta-analysis of randomized controlled trials.
DATA SOURCES
PubMed, Embase, the Cochrane Library, Ovid, ProQuest, Scopus, the Chinese BioMedical Literature Database, China National Knowledge Internet, the China Science and Technology Journal Database, and the Wanfang Data Knowledge Service Platform were used as sources.
ELIGIBILITY CRITERIA FOR SELECTING STUDIES
We included randomized controlled trials including PGE1 for the treatment of intraoperative microcirculatory disorders and major cardiovascular adverse events in emergency PCI in people with AMI. Independent data extraction was conducted, and study quality was assessed. The meta-analysis was carried out by using random effects models to calculate the risk ratio (RR) of microcirculatory disorders between groups receiving PGE1 and those receiving placebo, nitroglycerin, or tirofiban.
MAIN OUTCOME MEASURES
The primary endpoint of the study was the incidence of microcirculatory disturbances. Secondary outcomes included corrected thrombolysis in myocardial infarction (TIMI) frame count (cTFC), the percentage of patients with TIMI myocardial perfusion grade 3 (TMPG3), and the percentage of patients with myocardial blush grade 3 (MBG3) as efficacy indicators. Additionally, major adverse cardiovascular events (MACE) at 30 days and 180 days were assessed as safety indicators.
RESULTS
There were 18 trials involving a total of 1458 participants. PGE1 significantly reduced the occurrence of microcirculation disorders compared with conventional medications and placebo [risk ratio 0.48, 95% confidence interval (CI) 0.36-0.63, I = 46%; cTFC (RR -4.74, 95% -6.85 to -2.63, I 93%); percentage of patients with TMPG3 (RR 1.34, 95% CI 1.07-1.68, I 70%) or MBG3 (RR 1.33, 95% CI 1.19-1.49, I 0%); major adverse cardiovascular events (MACEs) in 30 days (RR 0.48, 95% CI 0.27-0.86, I 0%); and MACEs in 180 days (RR 0.41, 95% CI 0.28-0.60, I 0%)].
CONCLUSIONS
We found that PGE1 decreased the occurrence of micro-circulation disturbance in AMI and enhanced the outcome of PCI. Additional studies should be conducted to confirm these findings.
PubMed: 38850398
DOI: 10.1007/s40256-024-00655-3 -
Molecular Nutrition & Food Research Jun 2024Alcoholic liver disease (ALD) is a global public health concern. Nobiletin, a polymethoxyflavone abundant in citrus fruits, enhances circadian rhythms and ameliorates...
SCOPE
Alcoholic liver disease (ALD) is a global public health concern. Nobiletin, a polymethoxyflavone abundant in citrus fruits, enhances circadian rhythms and ameliorates diet-induced hepatic steatosis, but its influences on ALD are unknown. This study investigates the role of brain and muscle Arnt-like protein-1 (Bmal1), a key regulator of the circadian clock, in nobiletin-alleviated ALD.
METHODS AND RESULTS
This study uses chronic ethanol feeding plus an ethanol binge to establish ALD models in Bmal1 and Bmal1 liver-specific knockout (Bmal1LKO) mice. Nobiletin mitigates ethanol-induced liver injury (alanine aminotransferase [ALT]), glucose intolerance, hepatic apoptosis, and lipid deposition (triglyceride [TG], total cholesterol [TC]) in Bmal1 mice. Nobiletin fails to modulated liver injury (ALT, aspartate aminotransferase [AST]), apoptosis, and TG accumulation in Bmal1LKO mice. The expression of lipogenic genes (acetyl-CoA carboxylase alpha [Acaca], fatty acid synthase [Fasn]) and fatty acid oxidative genes (carnitine pamitoyltransferase [Cpt1a], cytochrome P450, family 4, subfamily a, polypeptide 10 [Cyp4a10], and cytochrome P450, family4, subfamily a, polypeptide 14 [Cyp4a14]) is inhibited, and the expression of proapoptotic genes (Bcl2 inteacting mediator of cell death [Bim]) is enhanced by ethanol in Bmal1 mice. Nobiletin antagonizes the expression of these genes in Bmal1 mice and not in Bmal1LKO mice. Nobiletin activates protein kinase B (PKB, also known as AKT) phosphorylation, increases the levels of the carbohydrate response element binding protein (ChREBP), ACC1, and FASN, and reduces the level of sterol-regulatory element binding protein 1 (SREBP1) and phosphorylation of ACC1 in a Bmal1-dependent manner.
CONCLUSION
Nobiletin alleviates ALD by increasing the expression of genes involved in fatty acid oxidation by increasing AKT phosphorylation and lipogenesis in a Bmal1-dependent manner.
PubMed: 38850176
DOI: 10.1002/mnfr.202300833 -
Journal of Molecular and Cellular... Jun 2024An increasing body of evidence suggests a pivotal role for the microvasculature in the development of cardiovascular disease. A dysfunctional coronary microvascular... (Review)
Review
An increasing body of evidence suggests a pivotal role for the microvasculature in the development of cardiovascular disease. A dysfunctional coronary microvascular network, specifically within endothelial cells-the inner most cell layer of vessels-is considered a strong, independent risk factor for future major adverse cardiac events. However, challenges exist with evaluating this critical vascular bed, as many of the currently available techniques are highly invasive and cost prohibitive. The more easily accessible peripheral microcirculation has surfaced as a potential surrogate in which to study mechanisms of coronary microvascular dysfunction and likewise may be used to predict poor cardiovascular outcomes. In this review, we critically evaluate a variety of prognostic, physiological, and mechanistic studies in humans to answer whether the peripheral microcirculation can add insight into coronary microvascular health. A conceptual framework is proposed that the health of the endothelium specifically may link the coronary and peripheral microvascular beds. This is supported by evidence showing a correlation between human coronary and peripheral endothelial function in vivo. Although not a replacement for investigating and understanding coronary microvascular function, the microvascular endothelium from the periphery responds similarly to (patho)physiological stress and may be leveraged to explore potential therapeutic pathways to mitigate stress-induced damage.
PubMed: 38848808
DOI: 10.1016/j.yjmcc.2024.06.002