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OBJECTIVE: To understand arterial remodeling and the pathophysiology of arterial diseases, it is necessary to understand the baseline qualities and variations in arterial structure. Arteries could differ in wall thickness, laminar structure, and laminar fenestration depending on their position within the arterial tree. We endeavored to evaluate and compare the extracellular matrix structure of different arteries throughout the arterial tree, from the aorta to the adductor muscle arteriole, with a particular focus on the internal elastic lamina (IEL). METHODS: Arterial segments were harvested from male Sprague-Dawley rats and imaged using multiple modalities. En face scans by multiphoton microscopy were used to compare native-state adventitial collagen undulation and IEL fenestration. RESULTS: Collagen undulation was similar across most examined arteries but straighter in the skeletal muscle arterioles (P < .05). The elastic lamellae showed several differences. The IEL fenestrae were similar in average size among abdominal aorta and celiac, renal, common iliac, and common femoral arteries (range, 14-24 µm2), with wide within-vessel variance (square of the standard deviation, 462-1904 µm4). However, they tended to be smaller (9.08 µm2) and less variable (square of the standard deviation, 88.3 µm4) in the popliteal artery. Fenestrae were greater in number in the superior mesenteric artery (SMA; 6686/mm2; P < .05) and profunda femoris artery (PFA; 11,042/mm2; P < .05) compared with the other examined vessels, which ranged in surface density from 3143/mm2 to 4362/mm2. The SMA and PFA also showed greater total fenestration as a proportion of the IEL surface area (SMA, 15.04%; P < .05; PFA, 24.11%; P < .001) than the other examined arteries (range of means, 4.7%-9.4%). The arteriolar IEL was structurally distinct, comparable to a low-density wireframe. Other structural differences were also noted, including differences in the number of medial lamellae along the arterial tree. CONCLUSIONS: We found that vessels at different locations along the arterial tree differ in structure. The SMA, PFA, and intramuscular arterioles have fundamental differences in the extracellular matrix structure compared with other arteries. Location-specific features such as the medial lamellae number and elastic laminar structure might have relevance to physiology and confer vulnerabilities to the development of pathology.

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Abstract Introduction: Calciphylaxis is an infrequent disease that almost exclusively affects patients with chronic kidney disease, although cases have been observed in patients without renal function impairment. The diagnosis is mainly made by clinical manifestations and subsequently confirmed by radiological and histological study. The optimal treatment is not known, although there is a consensus that a multifactorial approach is required. Clinical Case: A 68-year-old woman on hemodialysis for 2 years, who presented a painful nodular lesion in the left thigh, a skin biopsy was performed resulting in a diagnosis of calciphylaxis. Treatment and Outcome: Treatment was started with intravenous sodium thiosulfate. Pamidronate is added intravenously, three months later, due to an unfavorable evolution. After 6 months of treatment, improvement in nodular lesions and healing of the ulcerated lesion was observed to be generally well tolerated treatment. Conclusion: The combined treatment of sodium thiosulfate, pamidronate and calcitomimetics has been effectiveand safe for the treatment of calciphylaxis, inducing complete remission.

Resumen: Introducción: La calcifilaxis es una enfermedad infrecuente que afecta casi exclusivamente a pacientes con insuficiencia renal, aunque se han observado casos en pacientes sin deterioro de la función renal. El diagnóstico es clínico confirmándose con estudio radiológico e histológico. No se conoce con exactitud el tratamiento óptimo, aunque hay consenso en que se requiere un abordaje multifactorial. Caso Clínico: Mujer de 68 años en hemodiálisis desde hace 2 años, que presenta una lesión nodular dolorosa en muslo izquierdo, resultando un diagnostico compatible con calcifilaxis, tras biopsia cutánea. Tratamiento y resultado: Inicia tratamiento con tiosulfato de sodio vía venosa. Tres meses más tarde y ante la evolución desfavorable, se añade al tratamiento pamidronato vía intravenosa. Tras 6 meses de tratamiento se observa mejoría de las lesiones nodulares y cicatrización de la lesión ulcerada, habiéndose experimentado buena tolerancia. Conclusión: El tratamiento combinado de tiosulfato de sodio, pamidronato y calcimiméticos ha resultado efectivo y seguro para el tratamiento de la calcifilaxis, induciendo su remisión completa.

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Abstract Background: Alterations in the structure of resistance vessels contribute to elevated systemic vascular resistance in hypertension and are linked to sympathetic hyperactivity and related lesions in target organs. Objective: To assess the effects of exercise training on hemodynamic and autonomic parameters, as well as splenic arteriolar damages in male Wistar Kyoto (WKY) and Spontaneously Hypertensive Rats (SHR). Methods: Normotensive sedentary (WKYS) and trained (WKYT) rats, and hypertensive sedentary (SHRS) and trained (SHRT) rats were included in this study. After 9 weeks of experimental protocol (swimming training or sedentary control), arterial pressure (AP) and heart rate (HR) were recorded in freely moving rats. We assessed the autonomic control of the heart by sympathetic and vagal autonomic blockade. Morphometric analyses of arterioles were performed in spleen tissues. The statistical significance level was set at p < 0.05. Results: Resting bradycardia was observed in both trained groups (WKYT: 328.0 ± 7.3 bpm; SHRT: 337.0 ± 5.2 bpm) compared with their respective sedentary groups (WKYS: 353.2 ± 8.5 bpm; SHRS: 412.1 ± 10.4 bpm; p < 0.001). Exercise training attenuated mean AP only in SHRT (125.9 ± 6.2 mmHg) vs. SHRS (182.5 ± 4.2 mmHg, p < 0.001). The WKYT showed a higher vagal effect (∆HR: 79.0 ± 2.3 bpm) compared with WKYS (∆HR: 67.4 ± 1.7 bpm; p < 0.05). Chronic exercise decreased sympathetic effects on SHRT (∆HR: -62.8 ± 2.8 bpm) in comparison with SHRS (∆HR: -99.8 ± 9.2 bpm; p = 0.005). The wall thickness of splenic arterioles in SHR was reduced by training (332.1 ± 16.0 µm2 in SHRT vs. 502.7 ± 36.3 µm2 in SHRS; p < 0.05). Conclusions: Exercise training attenuates sympathetic activity and AP in SHR, which may be contributing to the morphological improvement of the splenic arterioles.

Resumo Fundamento: Alterações na estrutura dos vasos de resistência contribuem para elevar a resistência vascular sistêmica na hipertensão, estando ligadas à hiperatividade simpática e lesões em órgãos-alvo. Objetivo: Avaliar os efeitos do treinamento físico nos parâmetros hemodinâmicos e autônomos, assim como as lesões arteriolares esplênica em ratos machos Wistar Kyoto (WKY) e espontaneamente hipertensos (SHR). Métodos: Ratos normotensos sedentários (WKYS) e treinados (WKYT), e ratos hipertensos sedentários (SHRS) e treinados (SHRT) foram incluídos neste estudo. Após nove semanas de aplicação do protocolo experimental (treinamento de natação ou controle sedentário), registraram-se a pressão arterial (PA) e a frequência cardíaca (FC) dos ratos em movimento livre. Avaliamos o controle autônomo do coração através de bloqueio autônomo simpático e vagal. Análises morfométricas das arteríolas esplênicas foram realizadas. Adotou-se o nível de significado estatístico de p < 0,05. Resultados: Observou-se bradicardia de repouso nos dois grupos treinados (WKYT: 328,0 ± 7,3 bpm; SHRT: 337,0 ± 5,2 bpm) em comparação aos seus respectivos grupos sedentários (WKYS: 353,2 ± 8,5 bpm; SHRS: 412,1 ± 10,4 bpm; p < 0,001). O treinamento físico atenuou a PA média apenas no grupo SHRT (125,9 ± 6,2 mmHg vs. 182,5 ± 4,2 mmHg no SHRS; p < 0,001). O grupo WKYT mostrou maior efeito vagal (∆FC: 79,0 ± 2,3 bpm) em comparação ao grupo WKYS (∆FC: 67,4 ± 1,7 bpm; p < 0,05). Exercício crônico diminuiu os efeitos simpáticos em SHRT (∆FC: -62.8 ± 2.8 bpm) em comparação a SHRS (∆FC: -99,8 ± 9,2 bpm; p = 0,005). A espessura da parede das arteríolas esplênicas nos SHR foi reduzida pelo treinamento (332,1 ± 16,0 µm2 nos SHRT vs. 502,7 ± 36,3 µm2 nos SHRS; p < 0,05). Conclusões: O treinamento físico atenua a atividade simpática e a PA em SHR, o que pode contribuir para melhorar a morfologia das arteríolas esplênicas.

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INTRODUCTION: Calciphylaxis is an infrequent disease that almost exclusively affects patients with chronic kidney disease, although cases have been observed in patients without renal function impairment. The diagnosis is mainly made by clinical manifestations and subsequently confirmed by radiological and histological study. The optimal treatment is not known, although there is a consensus that a multifactorial approach is required. CLINICAL CASE: A 68-year-old woman on hemodialysis for 2 years, who presented a painful nodular lesion in the left thigh, a skin biopsy was performed resulting in a diagnosis of calciphylaxis. TREATMENT AND OUTCOME: Treatment was started with intravenous sodium thiosulfate. Pamidronate is added intravenously, three months later, due to an unfavorable evolution. After 6 months of treatment, improvement in nodular lesions and healing of the ulcerated lesion was observed to be generally well tolerated treatment. CONCLUSION: The combined treatment of sodium thiosulfate, pamidronate and calcitomimetics has been effectiveand safe for the treatment of calciphylaxis, inducing complete remission.

INTRODUCCIÓN: La calcifilaxis es una enfermedad infrecuente que afecta casi exclusivamente a pacientes con insuficiencia renal, aunque se han observado casos en pacientes sin deterioro de la función renal. El diagnóstico es clínico confirmándose con estudio radiológico e histológico. No se conoce con exactitud el tratamiento óptimo, aunque hay consenso en que se requiere un abordaje multifactorial. CASO CLÍNICO: Mujer de 68 años en hemodiálisis desde hace 2 años, que presenta una lesión nodular dolorosa en muslo izquierdo, resultando un diagnostico compatible con calcifilaxis, tras biopsia cutánea. TRATAMIENTO Y RESULTADO: Inicia tratamiento con tiosulfato de sodio vía venosa. Tres meses más tarde y ante la evolución desfavorable, se añade al tratamiento pamidronato vía intravenosa. Tras 6 meses de tratamiento se observa mejoría de las lesiones nodulares y cicatrización de la lesión ulcerada, habiéndose experimentado buena tolerancia. CONCLUSIÓN: El tratamiento combinado de tiosulfato de sodio, pamidronato y calcimiméticos ha resultado efectivo y seguro para el tratamiento de la calcifilaxis, induciendo su remisión completa.

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ABSTRACT Objective. To determine the effect of hypobaric hypoxia exposition in pulmonary arterioles expression of endothelin-1 (ET-1). Materials and methods. Two groups of commercial broiler chickens were used: one of them were raised at 2638 (hypobaric hypoxia) and the other one at 300 m (relative normoxia) above sea level. Incidence of pulmonary hypertension (PH) was evaluated by calculating the cardiac mass index values and ET-1 protein expression was established in pulmonary arterioles by immunohistochemistry and morphometry. Results . ET-1 expression was higher in arterioles of animals exposed to hypoxia as compared to the low altitude exposed broilers (p<0.01). Arterioles from pulmonary hypertensive chickens (PHC) showed ET-1 higher expression than arterioles from healthy chickens (non-hypertensive, NHC) at low altitude, those exposed to hypobaric hypoxia (p<0.01). 53% of chickens subjected to altitude conditions developed pulmonary hypertension. Under normoxia, no chickens developed that pathology. Conclusions. Quantitative characteristics and sites of ET-1 expression in the lungs are important in the understanding of PH pathogenesis in broilers and the adapting mechanisms to hypobaric hypoxia, as to design new pharmacological approaches. This is a first approach which accounts for the abovementioned features in broilers subjected to natural conditions of normoxia and hypobaric hypoxia.

RESUMEN Objetivo. Determinar el efecto de la exposición a hipoxia hipobárica sobre la expresión de Endotelina-1 en arteriolash pulmonares. Material y métodos. Se utilizaron 2 grupos de pollos de engorde de una estirpe comercial: uno de ellos criados a 2638 y el otro, a 300 m de altitud. La incidencia de HAP se evaluó según los valores del índice de masa cardiaca y se compararon los niveles de expresión de la proteína ET-1 en arteriolas pulmonares de pollos de engorde sanos y enfermos por HAP mediante inmunohistoquímica y morfometría. Resultados. La expresión de la proteína ET-1 fue mayor en las arteriolas de los pollos expuestos a hipoxia hipobárica que en los criados bajo condiciones de normoxia relativa (p<0.01). Los animales enfermos por HAP presentaron mayor expresión de la proteína ET-1 en las arteriolas pulmonares que los animales sanos ubicados en las dos altitudes (p<0.01). 53% de los animales desarrollaron hipertensión pulmonar y ninguno de los mantenidos en normoxia lo hicieron. Conclusiones. El conocimiento de las características cuantitativas y lo sitios de expresión de la ET-1 son elementos importantes para entender aún más la patogenia de la HAP y el diseño de fármacos para su control. Este estudio constituye la primera aproximación cuantitativa relacionada con la expresión de ET-1 en pollos de engorde con HAP de origen hipóxico no inducida.

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The arterial integrity of the "critical zone" of the rotator cuff has led to much uncertainty regarding rotator cuff tendinopathy. As the region of the supraspinatus tendon is the most common area affected by impingement, its central aspect is situated approximately 10 mm from the insertion at the greater humeral tubercle. Although many studies have investigated the vascularity of the "critical zone", there still appears to be lack of consensus regarding its extent. Through the employment of gross dissection and standard histology analysis of twenty-five adult bilateral cadaveric scapulo-humeral regions (n = 50), this study aimed to quantify the degree of vascularity, or lack thereof, within the "critical zone" by evaluating its relative morphometric features. The demographic representation of the sample was also considered. Results: i) Mean diameter of arteriole lumen: 91.6±75.2 µm; ii) Mean diameter of entire arteriole: 119.8±87.1 µm; iii) Mean arteriole wall thickness: 15.1±9.5 µm; iv) Mean area occupied by an arteriole: 20644.4±3358.0 µm2; v) Mean number of arterioles within "critical zone": 14.6±8.7. All tissue samples displayed a scarce distribution of arterioles along the musculo-tendinous junction relative to the "critical zone". A directly proportional relationship between the morphometric parameters was indicated by positive strong correlations and accompanying statistically significant P values. As 66 % of the number of arterioles within the "critical zone" were distributed between the minimum value and the upper quartile, it was postulated to be hypovascular, therefore confirming the findings of previous studies.

La integridad arterial de la "zona crítica" del manguito rotador ha dado lugar a una gran incertidumbre con respecto a la tendinitis del mismo. A medida que la región del tendón del músculo supraespinoso sea el área más común afectada por el impacto, su aspecto central estará situado aproximadamente a 10 mm desde la inserción en el tubérculo mayor del húmero. Aunque muchos estudios han investigado la vascularización de la "zona crítica", aún parece existir falta de consenso en cuanto a su extensión. A través de la disección macroscópica y análisis de la histología normal de ambas regiones escápulo-humerales, se realizó en 25 cadáveres adultos (n = 50), este estudio que tuvo como objetivo cuantificar el grado de vascularización, o su ausencia, dentro de la "zona crítica" mediante la evaluación de su características morfométricas. También se consideró la representación demográfica de la muestra. Resultados: i) La media de diámetro de lumen de las arteriolas: 91,6 ± 75.2 µm; ii) El diámetro medio de la totalidad de las arteriolas: 119,8 ± 87.1 µm; iii) la media del espesor de la pared de las arteriolas: 15,1 ± 9.5µm; iv) La media de la zona ocupada por una arteriola: 20.644,4 ± 3358.0 µm2; v) La media de las arteriolas dentro de la "zona crítica": 14,6 ± 8,7. Todas las muestras de tejidos tenían una escasa distribución de las arteriolas a lo largo de la unión músculo-tendinosa con relación a la "zona crítica". Una relación directamente proporcional entre los parámetros morfométricos indica fuertes correlaciones positivas y junto a valores de P estadísticamente significativos. Como el 66 % de las arteriolas dentro de la "zona crítica" se distribuyeron entre el valor de cuartil mínimo y superior, se postuló como hipovascular, por lo tanto confirma los resultados de estudios anteriores.

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Circulating adiponectin has been related to vascular diseases, but few studies examined the relationship between plasma adiponectin and microvascular abnormalities among hypertensive individuals. We tested the association between plasma adiponectin level and retinal vessel calibers in patients with hypertension.This study included 172 patients with confirmed hypertension, aged 18-80 years. Subjects with recent cardiovascular events, advanced heart failure and end-stage renal disease were excluded. Arteriolar and venular calibers were measured in retinographies using a microdensitometric image-processing method. Blood pressure was measured using a validated oscillometric device. We observed a statistically significant inverse association between plasma adiponectin and arteriolar caliber among participants aged 60 years or older after controlling for confounders (Adjusted ß = -0.42; P = .001). In the final model, HbA1C and low-density lipoprotein also remained independently associated with arteriolar caliber. There was no association of adiponectin with venular caliber and retinal vessel calibers in participants <60 years old.Adiponectin is inversely associated with retinal arteriolar caliber in elderly hypertensive participants, suggesting that plasma adiponectin may be a marker of microvascular damage and of higher cardiovascular risk in this age stratum.

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Neuronal activity must be tightly coordinated with blood flow to keep proper brain function, which is achieved by a mechanism known as neurovascular coupling. Then, an increase in synaptic activity leads to a dilation of local parenchymal arterioles that matches the enhanced metabolic demand. Neurovascular coupling is orchestrated by astrocytes. These glial cells are located between neurons and the microvasculature, with the astrocytic endfeet ensheathing the vessels, which allows fine intercellular communication. The neurotransmitters released during neuronal activity reach astrocytic receptors and trigger a Ca(2+) signaling that propagates to the endfeet, activating the release of vasoactive factors and arteriolar dilation. The astrocyte Ca(2+) signaling is coordinated by gap junction channels and hemichannels formed by connexins (Cx43 and Cx30) and channels formed by pannexins (Panx-1). The neuronal activity-initiated Ca(2+) waves are propagated among neighboring astrocytes directly via gap junctions or through ATP release via connexin hemichannels or pannexin channels. In addition, Ca(2+) entry via connexin hemichannels or pannexin channels may participate in the regulation of the astrocyte signaling-mediated neurovascular coupling. Interestingly, nitric oxide (NO) can activate connexin hemichannel by S-nitrosylation and the Ca(2+)-dependent NO-synthesizing enzymes endothelial NO synthase (eNOS) and neuronal NOS (nNOS) are expressed in astrocytes. Therefore, the astrocytic Ca(2+) signaling triggered in neurovascular coupling may activate NO production, which, in turn, may lead to Ca(2+) influx through hemichannel activation. Furthermore, NO release from the hemichannels located at astrocytic endfeet may contribute to the vasodilation of parenchymal arterioles. In this review, we discuss the mechanisms involved in the regulation of the astrocytic Ca(2+) signaling that mediates neurovascular coupling, with a special emphasis in the possible participation of NO in this process.

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There is accumulating evidence that physical inactivity, associated with the modern sedentary lifestyle, is a major determinant of hypertension. It represents the most important modifiable risk factor for cardiovascular diseases, which are the leading cause of morbidity and mortality for both men and women. In addition to involving sympathetic overactivity that alters hemodynamic parameters, hypertension is accompanied by several abnormalities in the skeletal muscle circulation including vessel rarefaction and increased arteriole wall-to-lumen ratio, which contribute to increased total peripheral resistance. Low-intensity aerobic training is a promising tool for the prevention, treatment and control of high blood pressure, but its efficacy may differ between men and women and between male and female animals. This review focuses on peripheral training-induced adaptations that contribute to a blood pressure-lowering effect, with special attention to differential responses in male and female spontaneously hypertensive rats (SHR). Heart, diaphragm and skeletal muscle arterioles (but not kidney arterioles) undergo eutrophic outward remodeling in trained male SHR, which contributed to a reduction of peripheral resistance and to a pressure fall. In contrast, trained female SHR showed no change in arteriole wall-to-lumen ratio and no pressure fall. On the other hand, training-induced adaptive changes in capillaries and venules (increased density) were similar in male and female SHR, supporting a similar hyperemic response to exercise.

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Objetivo: checar se poluentes do ar urbano de São Paulo induzem alterações sangüíneas e cardiopulmonares. MM: camundongos Balb/c foram expostos por 7, 14, 21, 30 e 45 dias em 3 câmaras: Limpa (controle), Intermediária (seletiva ao PM) e Suja (ar externo). Após exposição, os animais foram ventilados (FlexiVent) e coletados dados de mecânica pulmonar, sangue, coração e pulmão. Foram registrados PM, CO, SO2 e NO2 diários. Resultados: aos 21 e 45 dias coincidentes com picos de poluição houve aumento da resistência de via aérea (45d p=0,012), leucocitose (21d p < 0,001 e 45d p=0,039) e vasoconstricção pulmonar (21d p=0,034) nos animais da Câmara Suja, sem alteração de coronárias. Nenhum poluente excedeu limites de qualidade de ar.

Objective: verify if air pollution of São Paulo city induces alterations in blood and cardiopulmonary systems. MM: Balb/c mice were exposed during 7, 14, 21, 30 and 45 days to 3 chambers: Clean (control), Intermediate (PM only) and Dirty (external air). After exposure, animals were ventilated (FlexiVent) and collected lung mechanics data and blood, heart and lung. PM, CO, SO2 e NO2 were measured daily. Results: on day 21 and 45, coincidently to peak of pollutions, there was proximal airway resistance increase (45d p=0.012), leukocytosis (21d p < 0.001 and 45d p=0.039) and vasoconstriction of peribronchiolar arterioles (21d p=0.034) in animals of Dirty Chamber with no alterations of coronaries. Neither pollutants exceeded the standard limits.

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