Impact of catheter ablation procedure on optical coherence tomography angiography findings in patients with ventricular arrhythmia

SUMMARY OBJECTIVE: Catheter ablation procedure may cause retinal complications associated with the risk of thromboembolism. We aimed to evaluate retina and optic disc microvascularity with optical coherence tomography angiography before and after the catheter ablation process in patients with ventricular arrhythmia. METHODS: A total of 40 eyes of 21 ventricular arrhythmia patients were included in this cross-sectional study. Demographic characteristics and ophthalmic examination findings of patients were recorded. optical coherence tomography angiography measurements were evaluated before (group 1) and after (group 2) catheter ablation. Optical coherence tomography angiography was applied to all eyes with 6×6 mm sections for the macula and 4.5×4.5 mm sections for the optic nerve head. Foveal retinal thickness, peripapillary retinal nerve fiber layer thickness, vessel density in different parts of the retina, and optic disc were analyzed. RESULTS: The mean age of ventricular arrhythmia patients was 53.48±13.02 years. In all, 13 (61.9%) of the patients were males and 8 (38.1%) were females. There was no significant difference between the groups in terms of average, inferior, superior, and temporal retinal nerve fiber layer thicknesses, foveal avascular area, flow areas, superficial and deep vessel densities, and optic disc capillary densities of the optic disc. However, when compared with group 1, significantly lower values in foveal retinal thickness and higher values in nasal retinal nerve fiber layer thickness were observed in group 2 (248.42±20.50 vs. 247.20±20.44, p<0.001 and 94.22±18.43 vs. 96.12±20.18, p=0.044, respectively). CONCLUSION: Although foveal retinal thickness and nasal retinal nerve fiber layer thickness are affected in patients undergoing catheter ablation for ventricular arrhythmia, the stable retinal and optic disc vessel densities can be explained by the administration of effective anticoagulants during the procedure.

El fondo de ojo, una ventana a la microvasculatura del paciente hipertenso / The fundus, a window to microvasculature in hypertensive patients

Introducción: La hipertensión arterial constituye una de las enfermedades más frecuentes en la población general. En la actualidad llega a una prevalencia global del 30 al 45 %. La microcirculación retiniana puede considerarse como una representación anatómica de las características fisiológicas y funcionales de la circulación coronaria y cerebral. Objetivos: Profundizar en la relación existente entre los niveles de presión arterial y el daño del órgano diana, específicamente a través del fondo de ojo, así como de las posibles complicaciones oftalmológicas derivadas de la hipertensión arterial, y la comparación de algunas de las clasificaciones existentes sobre los cambios oftalmológicos que esta provoca. Métodos: Se emplearon los métodos de análisis-síntesis y análisis bibliográfico y documental. Los motores de búsqueda utilizados fueron: Google y Google Académico, y las bases de datos Hinari, SciELO Cuba, Pubmed, entre otras. Conclusiones: La retinopatía hipertensiva es una de las complicaciones adversas de la hipertensión arterial aguda o crónica. Por su parte, las oclusiones venosas y la formación de macroaneurismas, constituyen otras de gran envergadura. Mientras más eficaz sea el diagnóstico y seguimiento de los pacientes hipertensos, menos recursos se necesitarán para su tratamiento, y se evitarán así las complicaciones de otros órganos diana como el cerebro y el riñón, lo que provocaría en los pacientes una mayor discapacidad.

Introduction: arterial hypertension is one the most frequent diseases in general population. Nowadays, it reaches a global prevalence of 30 to 45 %. Retinal microcirculation can be considered as an anatomical representation of the physiological and functional characteristics of the coronary and cerebral circulation. Objectives: to delve into the relationship between blood pressure levels and target organ damage, specifically through the fundus, as well as the possible ophthalmological complications derived from arterial hypertension, and the comparison of some of the existing classifications on the ophthalmological changes that it causes. Methods: analysis - synthesis and bibliographic- documentary analyses were the used methods. Google and Google Scholar as well as Hinari, SciELO Cuba, Pubmed and others databases were the search engines. Conclusions: hypertensive retinopathy is one of the adverse complications of acute or chronic arterial hypertension. On the other hand, venous occlusions and the formation of macroaneurysms constitute other serious ones to consider. The more effective the diagnosis and follow-up of hypertensive patients, the fewer resources will be needed for their treatment, thus avoiding complications in other target organs such as the brain and kidney, which would cause greater disability in patients.

Mechanism of Tongmai Yangxin pill to reduce the no-reflow after myocardial ischemia and reperfusion by activating HIF-1α/eNOS signaling pathway up-regulated by GPER / 药学学报

The Tongmai Yangxin pill (TMYX) has potential clinical effects on no-reflow (NR); however, the effective substances and mechanisms by which this occurs remain unclear. This study evaluates the cardioprotective effects and molecular mechanisms of TMYX against NR. We used a myocardial NR rat model (2 h after myocardial ischemia and 2 h after reperfusion) to confirm the effect and mechanism of action of TMYX in alleviating NR. In vitro studies in isolated coronary microvasculature of NR rats and in silico network pharmacology analyses were performed to reveal the underlying mechanisms of TMYX and determine the main components, targets, and pathways of TMYX, respectively. The experiment was approved by the Ethics Committee of Hunan University of Chinese Medicine (LLBH-202212160001). TMYX showed therapeutic effects on NR by improving cardiac structure and function, reducing NR, ischemic areas, and cardiomyocyte injury, and decreasing the content of cardiac troponin I (cTnI). Moreover, the mechanism of TMYX predicted by network pharmacology is related to the hypoxia inducible factor-1 (HIF-1), nuclear factor kappa-B (NF-κB), and tumor necrosis factor (TNF) signaling pathways. TMYX increased the expression of G protein-coupled estrogen receptor (GPER), phospho-extracellular signal-regulated kinase (p-ERK), and HIF-1α. In vitro, TMYX enhanced the diastolic function of coronary microvascular cells; however, this effect was inhibited by GPER inhibitor (G-15), eNOS inhibitor (L-NAME), and sGC inhibitor (ODQ). This study integrates pharmacology and experimental evaluation to reveal that TMYX activates HIF-1α/eNOS signaling pathway by upregulating GPER to relax coronary microvessels, thereby significantly alleviating NR.

Short-term effects of anti-VEGF drugs on macular perfusion in patients with diabetic macular edema / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To evaluate the effect of Conbercept or Aflibercept on macular perfusion status in patients with diabetic macular edema(DME), and the changes in foveal avascular zone(FAZ)areas and capillary density in macular regions were measured quantitatively by optical coherence tomography angiography(OCTA).<p>METHODS: Twenty-six patients with DME received intravitreal injections of Conbercept or Alfibercept. The changes of FAZ areas, PERIM, AI, and macular vessel density in fovea of 300μm width(FD-300)were measured by OCTA in baseline 1, 7, and 30d after injection, and the effect of anti-VEGF drugs on blood circulation in macular area was analyzed. The best-corrected visual acuity(BCVA), central foveal thickness(CFT)were observed, the BCVA was converted to LogMAR. The changes of BCVA, CFT, FAZ, FD-300, PERIM, AI treated with anti-VEGF by methods repetitive measure analysis of variance on 1, 7, 30d after treatment were compared. Bonferroni was used to analyze the differences at different time points in pairwise comparison. Pearson correlation analysis was used to evaluate the correlation between changes in BCVA(LogMAR)and FAZ, CFT.<p>RESULTS: The FAZ area was 0.296±0.022mm² in baseline. After 1d drug injection, the FAZ increased to 0.339±0.024mm²(<i>P</i>=0.015). There was no significant difference in FAZ on the 7 and 30d after surgery(<i>P</i>=0.084, <i>P</i>=0.224). Compared with before treatment, BCVA and CFT decreased significantly, the anti-VEGF therapy was effective. The changes in PERIM, AI, and FD-300 did not reach significant level(<i>F</i>=2.598, <i>P</i>=0.059; <i>F</i>=0.438, <i>P</i>=0.726; <i>F</i>=0.594, <i>P</i>=0.621). The results of correlation analysis showed that BCVA(LogMAR)was positively correlated with FAZ and CFT(<i>r</i>=0.273, <i>P</i>=0.005; <i>r</i>=0.200, <i>P</i>=0.042)which had influence on BCVA.<p>CONCLUSION: With an increase in the avascular area of macular fovea was detected within 1d after intravitreal injection of anti-VEGF drug in patients with DME, and decrease in the area of avascular area in macular fovea after 1wk, accompanied by improved visual acuity. The selected appropriate index of OCTA can provide a reliable means to measure retinal circulation.

Optical coherence tomography angiography features of retinitis post-rickettsial fever

The intraocular manifestations of rickettisial retinitis include retinal vasculitis, maculopathy, optic neuritis, and neurosensory detachment. Extensive leakage of dye on the fundus fluorescein angiography may obscure visualization in eyes with retinitis. We report the vascular changes in eyes with rickettsial retinitis and its response to treatment using optical coherence tomography angiography. The microvascular abnormalities we noted were, capillary drop out areas corresponding to retinitis patches, vascular loops, and pruning of vessels. The choriocapillary slabs showed signal void areas. Post-treatment there was vascular remodeling with decrease in non-perfused area, appearance of new vascular lateral branching, and appearance of collaterals.

Microvascular anatomy of olfactory and accessory olfactory (vomeronasal) organs in adult Xenopus laevis: scanning electron microscopy of vascular corrosion casts / Anatomía microvascular de órganos olfatorios y accesorios (vomeronasal) en adultos Xenopus laevis: microscopía electrónica de barrido de moldes de corrosión vascular

Microvascular anatomy and histomorphology of olfactory and vomeronasal organs in adult Xenopus laevis Daudin were studied by scanning electron microscopy of vascular corrosion casts and paraplast embedded stained serial tissue sections. Results show that the arterial supply is bilaterally by terminal arterioles of the medial branch of the nasal artery and by the palatal artery. Arterioles give rise to a capillary meshwork characteristic for respiratory surfaces in principal chambers and in dorsal and caudal areas of middle chambers. Anterior and inferior areas of the middle chambers own a distinctly different capillary network with conspicuous short capillary loops. Loops have a dilated tip and extend in acute angles towards the chamber lumen. The vomeronasal organ (VNO) locates beneath the olfactory organ. It has a medial to lateral extension and attaches with its caudal circumference to the medial nasal glands. Its capillary bed displays rectangular meshes which preferentially orientate along the long axis of the VNO. Locally, capillaries form short hairpin-like or strongly twisted loops with dilated tips which point towards the lumen of the VNO. These capillaries slow-down blood velocity and may lead to an increased exchange of oxygen, nutrients and water-borne odorants in the middle chambers and of pheromones in the VNO. In the latter vascular structures are present which might serve as a vascular pump.

Se estudiaron la anatomía microvascular e histomorfología de los órganos olfatorios y vomeronasales de Xenopus laevis Daudin adultos, mediante microscopía electrónica de barrido de moldes de corrosión vascular y secciones de tejido seriadas, teñidas e incluídas en paraplast. Los resultados muestran que el suministro arterial es bilateral por arteriolas terminales de la rama medial de la arteria nasal y por la arteria palatina. Las arteriolas dan lugar a un lecho capilar característico de las superficies respiratorias en las cámaras principales y en las áreas dorsal y caudal de las cámaras intermedias. Las áreas anterior e inferior de las cámaras centrales poseen una red capilar significativamente diferente con llamativos bucles capilares cortos. Los bucles tienen una punta dilatada y se extienden en ángulos agudos hacia la luz de la cámara. El órgano vomeronasal (VNO) se ubica debajo del órgano olfatorio. Se extiende de medial a lateral y se une con su circunferencia caudal a las glándulas nasales mediales. El lecho capilar muestra mallas rectangulares que se orientan preferentemente a lo largo del eje longitudinal del VNO. Localmente, los capilares forman bucles cortos en forma de horquilla o fuertemente retorcidos con puntas dilatadas que apuntan hacia la luz del VNO. Estos capilares ralentizan la velocidad de la sangre y pueden conducir a un mayor intercambio de oxígeno, nutrientes y odorizantes, a base de agua en las cámaras intermedias y de feromonas, en el VNO. En este último, están presentes estructuras vasculares que podrían servir como una bomba vascular.

Progresses of pericytes in central nervous system microvascular diseases / 国际儿科学杂志

Pericyte is a type of important cellular constituents in the central nervous system (CNS),which is located at periphery of the microvessel wall,surrounded by basement membrane (BM) and connected with endothelial cell (EC) and astrocytes endfeet.As such important components of microvasculature,diverse functions have been assigned to pericytes,including control of brain blood flow,development and maintenance of the blood-brain barrier,regulation of the neuroinflammation and may function as pluripotent stem cells.The dysfunction of brain pericytes is associated with the progression of many CNS diseases.The occurrence of the disease leads to pericytes injury.The dysfunction of the brain pericytes make the disease worse.Increasing evidence suggests a highly specialized role for pericytes in a wide range of CNS diseases like Alzheimer's disease,stroke,subarachnoid hemorrhage,epilepsy and so on.

Regulation of Muscle Microcirculation in Health and Diabetes

Insulin increases microvascular perfusion and substrate exchange surface area in muscle, which is pivotal for hormone action and substrate exchange, by activating insulin signaling cascade in the endothelial cells to produce nitric oxide. This action of insulin is closely coupled with its metabolic action and type 2 diabetes is associated with both metabolic and microvascular insulin resistance. Muscle microvascular perfusion/volume can be assessed by 1-methylxanthine metabolism, contrast-enhanced ultrasound and positron emission tomography. In addition to insulin, several factors have been shown to recruit muscle microvasculature, including exercise or muscle contraction, mixed meals, glucagon-like peptide 1 and angiotensin II type 1 receptor (AT1R) blocker. On the other hand, factors that cause metabolic insulin resistance, such as inflammatory cytokines, free fatty acids, and selective activation of the AT1R, are capable of causing microvascular insulin resistance. Therapies targeting microvascular insulin resistance may help prevent or control diabetes and decrease the associated cardiovascular morbidity and mortality.

Numerical simulation and post processing of tumor microvasculature / 医用生物力学

Objective In order to provide a more realistic microvasculature model for the study on tumor hemodynamics and drug delivery, a simulated tumor microvascular network was developed by the technique of numerical simulation and post processing. Method We constructed a tumor microvascular model with host arteriole venule system, in which the variation in vascular branching and dimensions was taken into account. A sensitivity analysis was made for the parameters of the model to evaluate the adjustability of simulated results. The connectivity of the vascular network was tested to ensure the integrity of the network. The vascular network was smoothed afterwards to reduce flow resistance resulting from numerical networks. Results The simulated results are consistent with the characteristics of real tumor microvasculature, which show intact circulation, local adjustability, high network connectivity and smooth degree. Conclusions This study provid a numerical microvasculature model for the research on tumor hemodynamics, drug delivery and vascular targeted therapy.

The Role of Angiopoietin-1 and Thrombospondin-1 in the Kidney of Rats Subject to 5/6 Nephrectomy / 华中科技大学学报（医学）（英德文版）

The expression of angiopoietin-1 (Ang-1) and thrombospondin-1 (TSP-1) in 5/6 subtotal nephrectomy (STN) rats model, and its correlation to the renal microvasculature injury were investi-gated. Rat 5/6 STN model was established in adult male SD rats, and the sham-operated group and 5/6 STN group were set up. The renal function and histopathological changes were examined at the 1 st, 2nd, 4th, 8th and 12th week after operation. The expression of Ang-1, TSP-1 and CD31 in renal tissues was detected by using immunohistochemistry. From 2nd to 8th week after operation, Ang-1 was significantly expressed in glomeruli of rats with STN. Ang-1 staining in glomeruli of STN group was increased significantly as compared with that in sham-operated group at 4th and 8th week after operation, and subsequently decreased after the 12th week. The expression of TSP-1 was increased significantly in STN group. As compared with sham-operated group, the CD31 expression was sig-nificantly down-regulated from the 2nd week. The expression orAng-1 mRNA was detected by using RT-PCR at the same time points. The expression of Ang-1 mRNA in renal tissue of rats with STN was significantly up-regulated at the 2rid, 4th and 8th week after operation as compared with that in STN group at other time points or in sham-operated group at the same time points, while decreased evidently at the 12th week as compared with that in sham-operated group. It is concluded that there are changes in the mRNA expression of Ang-1, and the significant up-regulation of the expression of TSP-1 in renal tissue of rats with STN, which may be involved in the remnant renal microvasculature injury.

Microvasculature in the Streptozotocin Induced Diabetic Rat Retina / 대한해부학회지

Diabetic retinopathy is characterized by the pericyte loss, microaneurysms and neovascularization eventually leads to blindness. The present study was examined changes of the microvasculature histochemically and immunochemically in the diabetic rat retina previously documented neuronal alterations, in order to verify the usefulness of the animal model of diabetes for the pathophysiology of angiogenesis. Diabetic condition was induced by a single intravenous injection of streptozotocin in Sprague-Dawley rats aged of 8weeks. The animals showing high blood glucose levels (above 300 mg/dL) were cared for 1, 4, 8, and 12 weeks, respectively. The retinas were processed for Griffonia simplicifolia isolection (GSI) B4 histochmistry, and anti-alpha-smooth muscle actin (alpha-SMA) and anti-NG2 immunochemical techniques. The retinal vasculature was well demarcated by endothelial profiles with GSIB4 histochemistry. alpha-SMA immunoreactivity appeared in the arterioles and the primary capillaries, and NG2 in the arterioles and the whole capillary beds. Changes evoked by diabetes were largely occurred in the capillary. Compared to the retina at normal state, the capillary networks were more complicated, enlarged, and dense. NG2 reactivity was reduced especially under the cytoplasmic processes of the pericytes. In the near periphery of the capillary mainly in the ganglion cell layer of the diabetes, GSIB4 reactive microglia were distributed. These results suggest that the retinal microvasculature showed the precedent events of neovascularization due to diabetes and rat model of diabetes is useful for study of neovascularization mechanism of the diabetic retinopathy.

Correlation Between the Serum Bilirubin Level and the Coronary Microvascular Integrity in Diabetic Patients

BACKGROUND AND OBJECTIVES: Bilirubin has a protective role in suppressing atherosclerosis and coronary artery disease by its potent physiological antioxidant properties. There has been no comparative study on the relation between the bilirubin level and the coronary microvascular function in diabetic patients. This study investigated whether the bilirubin level correlates with the coronary microvascular integrity in diabetes by assessing the coronary flow velocities after successful percutaneous coronary intervention (PCI). SUBJECTS AND METHODS: Fifty patients (31 males and 19 females, mean age 60+/-11) with angina and who received elective PCI were studied. Using an intracoronary Doppler wire, the coronary flow velocity reserve (CFR), the hyperemic microvascular resistance index and the phasic coronary flow velocity patterns were measured after PCI. RESULTS: The mean value of the fasting blood glucose was 211+/-88 mg/dL, the man value of glycated hemoglobin A1c (HbA1c) was 8.1+/-1.6% and the mean serum total bilirubin level was 0.59+/-0.21 mg/dL. CFR was significantly correlated with the serum bilirubin level (r=0.485, p<0.001), HbA1c (r=-0.432, p=0.003) and the fasting blood glucose (r=-0.361, p=0.011). On multivariate analysis, HbA1c, bilirubin and left ventricular hypertrophy showed independent relationships with coronary microvascular dysfunction (p=0.003, p=0.004, p=0.033, respectively). CONCLUSION: These results suggest that glycemic control and elevated serum bilirubin may protect diabetic patients from coronary microvascular dysfunction.

Gastrocnemius skeletal muscle microvasculature and neuromuscular junction alterations in mice with experimental acute chagas infection / Alteraciones en la microvasculatura y unión neuromuscular del músculo esquelético Gastrocnemius de ratones con infección experimental de Chagas agudo

A light and transmission electron microscopy study was performed in skeletal muscles (SM) Gastrocnemius (G) from mice experimentally infected with Trypanosoma cruzi to determine changes on microvessels (MV) and neuromuscular junction (NMJ) of G. In this study 10 male (mus musculus) (20 g) were infected subcutaneally with 1.10(4) bloodstream trypomastigotes M/DID/Ve/02/DSM strain. Five mice were kept as uninfected controls. The parasites induced a complete paralysis of the rear limbs and death while still in the acute Chagas´disease. The histopathology of SM showed inflammatory cell infiltration by mononuclear and polymorphonuclear leukocytes associated with marked parasitism in the muscle fibers of G. Indirect immunofluorescence revealed interstitial IgG deposit as bands regularly spaced along the nerve terminals at 40 days post-infection (pi). At this time T. cruzi antigens and intracellular amastigotes nests were also observed. The marked inflammatory response and morphological changes in the SM were confirmed by transmission electron microscopy. Capillary ultrastructure was seen to be altered, with points of cell cytoplasm discontinuity that appear to represent holes in the microvessel walls. This finding coincided with amastigote nests in myofibers, close contacts between trypomastigotes and endothelial cells and marked thickening of the basement membrane of the muscle vessels. Loss of capillary lumen and a process of ischemia also were observed in the SM of infected mice. The neuromuscular junction showed degeneration of intramuscular nerve fibers, reduction in the axon caliber, swollen mitochondrial, increase in the actin filaments and microtubules in the axoplasm, and swelling of the Schwann cells. Increase in the nerve terminal perimeter and most of the synaptic vesicles were localized near the presynaptic active zones and scarces in the axoplasm. At this stage of infection the changes findings in MV and NMJ of G infected with ...

Un estudio con microscopía de luz y electrónica de transmisión fue realizado en muestras del músculo esquelético (ME) Gastrocnemius (G) de ratones experimentalmente infectados con Trypanosoma cruzi, a fin de determinar las alteraciones en la microvasculatura y unión neuromuscular (UNM) de G durante la infección chagásica aguda. Un grupo de 10 ratones machos (mus musculus) NMRI (20 g), fueron infectados subcutáneamente con 1,10(4) tripomastigotes sanguícolas de la cepa M/DID/Ve/02/DSM. Cinco ratones NMRI no infectados fueron usados como control. Estos parásitos produjeron completa parálisis de las patas posteriores y muerte de los ratones durante la infección aguda. La histopatología del ME mostró infiltración de células mononucleares y leucocitos polimorfonucleares asociados con marcado parasitismo en la fibra muscular de G. La inmunofluorescencia indirecta reveló IgG a manera de bandas sobre el nervio terminal a los 40 días post-infección (pi). En este tiempo, antígeno y grupos de amastigotes de T. cruzi fueron observados en los cortes del ME. La marcada respuesta inflamatoria y las alteraciones morfológicas en el tejido muscular fueron verificadas por microscopía electrónica de transmisión. La ultraestructura de los capilares estuvo relacionada con puntos de discontinuidad en la microvasculatura. Este encuentro coincidió con la presencia de grupos de amastigotes dentro de las miofibrillas, estrecho contacto entre los tripomastigotes y las células endoteliales y marcado adelgazamiento de la membrana basal de los vasos sanguíneos. La pérdida del lumen capilar y un proceso de ischemia también fue observado en el G de los ratones infectados. La unión neuromuscular mostró degeneración de la fibra nerviosa intramuscular, reducción en el calibre del axón del nervio motor determinada por una retracción de la vaina de mielina, inflamación mitocondrial, aumento en los filamentos de actina y microtúbulos en el axoplasma e inflamación de las células ...

Ultraestructura de la microvasculatura en lesiones premalignas y malignas de la mucosa bucal / Microvasculature ultrastructure in premalignant and malignant lesions of oral mucosa

El proceso de angiogénesis y remodelado vascular es esencial para el crecimiento, la invasión y la metástasis tumoral. Los vasos sanguíneos tumorales presentan anormalidades estructurales y funcionales. El objetivo de este trabajo fue caracterizar las alteraciones ultraestructurales de la microvasculatura de displasias y carcinomas espinocelulares de la mucosa bucal como un modelo de progresión tumoral, mediante microscopía electrónica de transmisión convencional. Las alteraciones encontradas en los casos de displasia leve y moderada incluyeron la distribución y el número variable de las vesículas pinocíticas y cavéolas, así como la proliferación de algunos organelos. Asimismo, en ambos tipos de displasia se apreció la membrana basal reduplicada y el pericito en algunos casos se observó alterado. En los carcinomas espinocelulares bucales también se encontró el engrosamiento y reduplicación de la membrana basal. La hipertrofia del endotelio fue frecuente, con el edema del mismo y del pericito. Las prolongaciones del endotelio hacia la luz fueron observadas en las displasias leve y moderada y en los carcinomas bucales. Tales resultados podrían sugerir anormalidades en el funcionamiento de los capilares, en relación a cambios en la actividad metabólica y la permeabilidad de las células endoteliales y los pericitos.

O processo do angiogénesis e o remodelado vascular é essencial para o crescimento, a invasão e o metástasis do tumor. A embarcação de sangue presente do tumor estruturais e funcionais anomalias. O objetivo deste trabalho era caracterizar o ultrastructural alterações do microvasculatura dos displasias e dos carcinomas os espinocelulares da mucosa oral gostam de um modelo do tumor progressão, por meio do microscopio eletrônico da transmissão convencional. As alterações encontradas nos exemplos do displasia pesam e moderam incluíram a distribuição e o número variável do spinocíticase vesicles dos cavéolas, o proliferacion de alguns organelos. Também, em ambos os tipos de displasia a membrana basal do reduplicada estava engrossada e o pericito em alguns casos foi observado alterou-se. Em carcinomas orais os espinocelulares eram também engrossamento e reduplicación da membrana basal. Hipertrofia do endotelio era freqüente, com o edema do mesmo e o pericito. Os prolongations do endotelio para a luz foram observados dentro displasias ligeiros e moderados e os carcinomas orais. Tais resultados podiam sugerir anomalias na operação do capilar, com relação às mudanças na atividade metabolica e na permeabilidade das pilhas dos endoteliales e dos pericitos.

The process of angiogenesis and vascular remodelling is essential for tumor growth, invasion and metastasis. Tumor blood vessels show structural and functional abnormalities. The aim this work was characterize the ultrastructural alterations of microvasculature in dysplasias and squamous carcinomas of oral mucosa as a model of tumor progression by conventional transmission electron microscopy. Alterations included a variable distribution and number of pinocytotic vesicles and caveolae, as well as proliferation of some organelles in slight and moderate dysplasias. Likewise, the basement membrane looked reduplicated in both cases and pericytes in some cases was alterations. In oral squamous carcinomas capillary basement membrane was thickened and reduplicated. Endothelial hypertrophy was frequent with edema and also in the pericytes. Endothelial cell cytoplasm infoldings into the lumen were observed in slight and moderate dysplasias and oral squamous carcinoma. The results could suggest an abnormal capillary funtion in relation to metabolic activity and permeability of endothelial cells and pericytes.

Brain microvascular basement membrane damage and the expression of uPA and uPA mRNA in brain areas after focal cerebral ischemia/reperfusion in renovascular hypertensive stroke-prone rats / 中国病理生理杂志

AIM: To explore the structural changes of brain microvasculature and mechanism in microvascular lesion after focal cerebral ischemia with reperfusion. METHODS: Using the techniques of immunohistochemical staining, in situ hybridization,optical microscopy and transmission electron microscopy, the expression of uPA, uPA mRNA, and changes in miocrovascular structure were examined in ischemic focus and perifocal areas after focal cerebral ischemia 2 hours with various time points of reperfusion in stroke-prone renovascular hypertensive rats (RHRSP). RESULTS: The brain edema and hemorrhage were severe 12 hours to 3 days after reperfusion. Ultrastructural change showed that the damage characterizations of the basement membrane were degradation, defection, and exfoliated of basement membrane, while uPA, which attack the basememt membrane around cerebral capillaries and extra-cellular matrix, and uPA mRNA expression increased significantly in ischemic and perifocal areas 12 hour to 3 day after reperfusion. CONCLUSION: The main pathologic mechanism of brain edema and hemorrhage after cerebral ischemia with reperfusion may result from the basement membrane lesion of brain microvasculature. The increase in the expression of uPA in reperfusion area may be the main cause of the basement membrane lesion .

The investigation of microvasculature changes in osseous regeneration by guided tissue regeneration procedure

Morphometric Study for Muscular and Microvascular Remodeling of Left Ventricular Free Wall and Interventricular Septum in Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCMP) is characterized myofiber hypertrophy and structural remodeling with changes in the proportion of the muscular, vascular, and interstitial compartments. A study was done to determine the structural remodeling patterns and the role of microvasculature of hearts in HCMP. Forty-two postmortem hearts were analyzed including 14 from patients who died of HCMP (group 1), 8 patients with HCMP but who died from extracardiac causes (group 2), 10 patients with ischemic heart disease (group 3), and 10 normal adult hearts (group 4). Macro- and microscopic examination, immunohistochemical study using CD34 antibody, and morphometric studies using image analyzer were performed. Mean cardiac weight and wall thickness were significantly higher in the HCMP group. Myocardial hypertrophy, and a variety of myocardial disarray and fibrosis involved the whole area of the left ventricles with HCMP. The percentage areas of microvessels were 6.40 0.7 in group 1, 5.90 0.6 in group 2, 4.98 0.3 in group 3, 4.85 0.4 in group 4, respectively, and the numbers of microvessels were 198.0 20.7 in group 1, 230.0 22.3 in group 2, 211.7 11.2 in group 3, and 236.4 11.4 in group 4, respectively (mean SE). The percentage area of microvessels was significantly higher in group 1 than in other groups. However, the number of microvessels in that group was lower than in the other groups, although it was statistically insignificant. Since flow-dependent vasodilation is preserved in HCMP, we considered flow-dependent vasodilation the cause of the discrepancy between the area and the number of microvessels. Ischemic changes observed in chronic HCMP and related heart failure were considesed to be due to the relative deficiency of the coronary flow compared to the increasing cardiac mass.

Microvasculature change in the diagnosis of early esophageal carcinoma using magnifying endoscopy / 中华消化内镜杂志

Objective To study the detection rate of early esophageal carcinoma using magnifying endoscopy,and to evaluate the relationship between the imaging patterns of microvasculature change and his- tological diagnosis.Methods Two hundred and fourteen patients with esophageal mucosa roughness,ero- sion,plaque,abnormal color and indentation in conventional endoscopy and 16 healthy volunteers were en- rolled.The magnifying endoscopy images were graded as four patterns by intraepithelial papillary capillary loop(IPCL)changes after iodine dyeing.The biopsies underwent pathologic evaluation.The comparison be- tween the imaging patterns of endoscopy and histological diagnosiswas was evaluated.Results 80.4%(90/ 112)esophagitis was type 2,and 85.7%(12/14)early esophageal carcinoma was type 3 and type 4.The difference was significant between early esophageal carcinoma and normal mueosa(?~2=27.32,P

Study of the relationship between morphological characteristics of tumor microvasculature and blood supply type of primary hepatocellular carcinoma observed under DSA / 介入放射学杂志

Objective To discuss the relationship between morphological characteristics of tumor microvasculature and blood supply type of primary hepatic cell carcinoma (HCC) through DSA. Methods From Jan. 1998 to Feb.2002, 32 cases, male 26,female 6,aged 28-76 (mean 50.56?10.52) years, underwent preoperative digital subtraction angiography (DSA) without therapeutic embolization in the 301 hospital and 307 hospital. The intervals between DSA and curative resections were 13-70 (mean 31.89?19.11) days. The diameters of the tumors were 2-23 (8.05?6.17) cm. The blood supply type of tumor, the tumor microvasculature density(MVD), type and diameter of the tumor microvessels, width of tumor trabecular were recorded for these cases. The outcomes were then statistically analysized. Results ① Blood supply of the tumor observed on DSA tended to be positively correlated with type of the tumor microvasculature. ②MVD of hypovascular tumors were lower than those in moderate and hypervascular tumors.③The ratio of diameters between tumor microvessel to the trabeculae of the tumor went higher with the increase of HCC blood supply on DSA. Conclusions ①The density, the configuration and the distribution of tumor microvasculature were not evenly distributed in HCC. ②The features of tumor microvasculature possessed distinctive characteristics in different stages of tumor growth, simultaneously with some definite developing rules. ③ Distinct differences in morphological characteristics of tumor microvasculature between different blood supply types of HCC.

Endothelial Dysfuntion of Coronary Microvasculature in Patients with Chest Pain and Normal Coronary Angiograms

BACKGROUND: A group of patients with chest pain and normal coronary angiograms without spasm of epicardial artery is known to have decreased coronary flow reserve in response to vasodilatory stimuli, but the mechanisms responsible for the impairment of vasodilatory reserve are undefined. The purpose of this study was to determine whether dysfunction of coronary microvascular endothelium contributes to the reduced vasodilatory responses in patients with chest pain and normal coronary angiograms. METHODS: Twenty patients, 12(group A) with and 8(group B) without ST depression on exercise ECG or 24 hours ambulatory ECG. with chest pain and normal coronary angiograms and no spasm of epicardial coronary artery. were studied. As the endothelium-independent vasodilator, acetylcholine at doses of 20microg, 50microg and 100microg, and as the endothelium-independent vasodilator, nitroglycerin 200microg were infused into left coronary artery. The functional response of coronary vasomotion was studied with atrial pacing. By themodilution pacing catheter. great cardiac vein flow(GCVF) was measured. The changes in the diameter of proximal and distal of left anterior descending artery were analyzed. RESULTS: Intracoronary acetylcholine increased GCVF by 12.3% with 20microg(NS),by 38.9% with 50microg(p<0.05) and by 14.8% with 100microg(NS). The changes in GCVF with 20microg and 50microg dose of acetylcholine were positively related with those with atrial pacing(r=0.59 and r=0.62, respectively), but not at dose of 100microg(r=0.12). Thus, patients with diminished flow response with atrial pacing had reduced endothelium-dependent dilation with low dose acetylcholine. Also changes in GCVF with atrial pacing and acetylcholine were smaller in the patients of group A than group B. However, the changes in GCVF to nitroglycerin was not related with the changes with acetylcholine and did not differ between A and B group, indicating this vasodilatory response was not associated with the endothelium-independent vasodilation. Acetylcholine caused similar degree of change in diameter at proximal and distal epicardial artery in two groups and their changes were not related with changed in GCVF with acetylcholine, suggesting the changes in GCVF with acetylcholine were mainly influenced by the changes at the level of microvasculature. CONCLUSION: In patients with chest pain and normal coronary angiograms without spasm of epicardial artery, reduced vasodilatory response with atrial pacing was associated with the impairment of endothelium-dependent dilation at the level of coronary microvasculature, suggesting the endothelial dysfunction of coronary microvessels is one of the causes of inducible myocardial ischemia.