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1.
Vasc Health Risk Manag ; 15: 375-384, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695398

RESUMO

Background: Survivors of myocardial infarction (MI) are at high risk of new major adverse cardiovascular events (MACE). Coronary flow reserve (CFR) is a strong and independent predictor of MACE. Understanding the prevalence of impaired CFR in this patient group and identifying risk markers for impaired CFR are important steps in the development of personalized and targeted treatment for high-risk individuals with prior MI. Methods: PROFLOW is a prospective, exploratory, cross-sectional open study. We used information from the SCAAR (Swedish Coronary Angiography and Angioplasty Registry) to identify high-risk patients with a history of type-1 MI. We measured CFR non-invasively in a left anterior descending artery (LAD) using transthoracic Doppler echocardiography. Coronary flow velocity was measured at rest and at maximal flow after induction of hyperemia by intravenous infusion of adenosine (140 µg/kg/min). Independent predictors of CFR were assessed with multiple linear regression. Results: We included 619 patients. The median age was 69 (IQR 65-73), and 114 (18.4%) were women. Almost one-half of the patients, 285 (46.0%) had the multi-vessel disease, and 147 (23.7%) were incompletely revascularized. The majority were on optimal standard treatment eg ASA (93.1%), statins (90.0%), ACEI/ARB (82.6%) and beta-blockers (80.8%). The majority, 547 (88.4%) had no angina pectoris, and 572 (92.2%) were in NYHA class I. Evaluation of CFR was possible in 611 (98.7%) patients. Mean CFR was 2.74 (±0.79 (mean ± SD)). A substantial number of patients (39.7%) had CFR ≤2.5. In a multiple linear regression model age, dyslipidemia, smoking, hypertension, body mass index, incomplete revascularization, and treatment with angiotensin receptor blockers were independent predictors of CFR. Conclusion: In this high-risk group of patients with prior MI, the prevalence of impaired CFR was high. Further risk stratification with CFR in addition to traditional cardiovascular risk factors may improve predictive accuracy for future MACE in this patient population.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Ecocardiografia Doppler , Reserva Fracionada de Fluxo Miocárdico , Infarto do Miocárdio/diagnóstico por imagem , Adenosina/administração & dosagem , Idoso , Velocidade do Fluxo Sanguíneo , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/terapia , Vasos Coronários/fisiopatologia , Estudos Transversais , Feminino , Humanos , Hiperemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Valor Preditivo dos Testes , Prevalência , Prognóstico , Estudos Prospectivos , Sistema de Registros , Fatores de Risco , Prevenção Secundária , Suécia/epidemiologia , Vasodilatadores/administração & dosagem
2.
Biomed Res ; 40(4): 145-152, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413235

RESUMO

We investigated the mechanisms by which propiverine hydrochloride influenced bladder activity in rats with pelvic venous congestion (PC) and urinary frequency. To create PC rats, female rats were anesthetized with isoflurane and the bilateral common iliac veins and bilateral uterine veins were ligated. At 4 weeks after ligation, we assessed voiding behaviour, locomotor activity, and urinary 8-hydroxydeoxyguanosine (8-OHdG) and nitric oxide metabolites (NOx). We also performed cystometry and measured mRNAs for nitric oxide synthase (NOS) and several receptors in the bladder wall. PC rats showed a decrease in locomotor activity and an increased frequency of urination. There was a decrease in endothelial NOS (eNOS), M3, and TRPV1 mRNA expression in the bladder wall, as well as an increase in inducible NOS (iNOS) mRNA. Administration of propiverine to PC rats increased locomotor activity to the level in sham rats, improved bladder function, decreased urinary 8-OHdG excretion, and increased urinary NOx excretion. In addition, propiverine increased neuronal NOS (nNOS) mRNA expression, and decreased expression of iNOS, M3 and TRPV1 mRNA in the bladder wall. Therefore, propiverine not only improved bladder dysfunction through its previously reported actions (anti-muscarinic effect, Ca antagonist effect, and inhibition of noradrenaline re-uptake), but also by reducing inflammation.


Assuntos
Benzilatos/farmacologia , Hiperemia/tratamento farmacológico , Doenças da Bexiga Urinária/tratamento farmacológico , Bexiga Urinária/fisiopatologia , Animais , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Hiperemia/metabolismo , Hiperemia/patologia , Hiperemia/fisiopatologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Inflamação/fisiopatologia , Óxido Nítrico Sintase Tipo I/biossíntese , Óxido Nítrico Sintase Tipo III/biossíntese , Ratos , Ratos Sprague-Dawley , Canais de Cátion TRPV/biossíntese , Bexiga Urinária/metabolismo , Bexiga Urinária/patologia , Doenças da Bexiga Urinária/metabolismo , Doenças da Bexiga Urinária/patologia , Doenças da Bexiga Urinária/fisiopatologia
3.
Optom Vis Sci ; 96(7): 507-512, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31274739

RESUMO

SIGNIFICANCE: The conjunctiva is an integral component of the ocular surface, and its vasculature forms a terminal vascular bed of the human internal carotid artery. No research on the response of conjunctival vasculature to ocular surface stimulation exists; however, it is essential to understand the local physiological and pathological responses to such a stimulus. PURPOSE: The purpose of this study was to characterize the ocular redness levels in healthy participants after the application of noxious corneal stimulation. METHODS: A computerized Belmonte pneumatic esthesiometer was used to determine detection thresholds (using ascending method of limits) and to randomly deliver mechanical and chemical stimuli from levels of detection threshold to twice the threshold in 50% steps to the central cornea of 15 healthy subjects. For each suprathreshold stimulus, a spectrophotometer was used to measure ipsilateral and contralateral conjunctival redness before and after delivery of the corneal stimulus. Redness between the stimulated and unstimulated eyes was analyzed using dependent t tests. The effects of stimulus intensity and modality on conjunctival redness were analyzed using repeated-measures analysis of variance (ANOVA). Tukey honestly significant difference tests were used for all post hoc analyses. P ≤ .05 was considered statistically significant. RESULTS: In mechanical and chemical stimulation experiments, the stimulated eye became redder than the unstimulated eye (all t tests, P > .05). On average, redness increased from baseline as the corneal stimulus intensity increased with corneal stimulation (ANOVA, P < .05). Chemical stimulation produced greater conjunctival redness than did mechanical stimulation at all stimulation levels (ANOVA, P < .05; all Tukey honestly significant difference tests, P < .05). CONCLUSIONS: Stimulation of the central cornea by noxious mechanical and chemical stimuli evokes a dose-dependent autonomic conjunctival redness response. Chemical stimulation of the cornea seems to evoke a greater response compared with mechanical stimulation. This study serves as a basis for the characterization of the local stimulus-response neural circuitry relating nociceptive ocular surface stimuli to autonomic responses.


Assuntos
Artéria Carótida Interna/fisiologia , Túnica Conjuntiva/irrigação sanguínea , Hiperemia/fisiopatologia , Estimulação Física , Estimulação Química , Adulto , Ar , Dióxido de Carbono/administração & dosagem , Córnea/fisiologia , Feminino , Voluntários Saudáveis , Humanos , Hiperemia/etiologia , Masculino , Sensação/fisiologia , Adulto Jovem
4.
Comput Methods Biomech Biomed Engin ; 22(12): 1009-1019, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31084210

RESUMO

Monitoring of skin blood flow oscillations related with mechanical activity of vessels is a very useful modality during diagnosis of peripheral hemodynamic disorders. In this study, we developed a new model and technique for real-time conversion of skin temperature into skin blood flow oscillations, and vice versa. The technique is based on the analogy between the thermal properties of the human skin and electrical properties of the special low-pass filter. Analytical and approximated impulse response functions for the low- and high-pass filters are presented. The general algorithm for the reversible conversion of temperature into blood flow is described. The proposed technique was verified using simulated or experimental data of cold stress, deep inspiratory gasp, and post-occlusive reactive hyperaemia tests. The implementation of the described technique will enable to turn a temperature sensor into a blood flow sensor.


Assuntos
Sistemas de Computação , Temperatura Cutânea/fisiologia , Pele/irrigação sanguínea , Temperatura Ambiente , Adulto , Algoritmos , Difusão , Feminino , Hemodinâmica , Humanos , Hiperemia/fisiopatologia , Masculino , Fluxo Sanguíneo Regional , Fatores de Tempo , Adulto Jovem
5.
Angiology ; 70(8): 719-725, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31137942

RESUMO

The effects of nicotine replacement therapy (NRT)-aided smoking cessation on vascular function are not fully clarified. We investigated 100 healthy smokers who were motivated to quit and received NRT for a 3-month period. Vascular endothelial function (measured by reactive hyperemia-peripheral arterial tonometry [RH-PAT]), arterial stiffness (measured by augmentation index [AI] and brachial-ankle pulse wave velocity [baPWV]), and systemic inflammation markers (including serum soluble intercellular adhesion molecule-1 [sICAM-1] and interleukin-1ß [IL-1ß]) were assessed at baseline and 3 and 12 months of follow-up. After 3 months of intervention, endothelial function, arterial stiffness, and inflammatory markers significantly improved (RH-PAT increased, AI and baPWV decreased, sICAM-1 and IL-1ß decreased, all P < .05) for the participants who abstained from smoking completely, but for those who did not abstained completely, RH-PAT, AI, baPWV, and IL-1ß remained unchanged. At 12 months follow-up, endothelial function (RH-PAT), arterial stiffness (AI and baPWV), and inflammatory markers (sICAM-1 and IL-1ß) were further improved in participants who abstained from smoking (P < .001), while the above parameters deteriorated in continued smokers (P < .05). In conclusion, vascular dysfunction can be reversible after NRT-aided smoking cessation in healthy smokers and vascular function could be further damaged if they continue smoking.


Assuntos
Hiperemia/tratamento farmacológico , Inflamação/tratamento farmacológico , Abandono do Hábito de Fumar , Dispositivos para o Abandono do Uso de Tabaco , Rigidez Vascular/fisiologia , Adolescente , Adulto , Idoso , Artérias/efeitos dos fármacos , Artérias/fisiopatologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Hiperemia/fisiopatologia , Inflamação/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fumantes , Dispositivos para o Abandono do Uso de Tabaco/efeitos adversos , Adulto Jovem
6.
Intern Med ; 58(10): 1383-1390, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31092771

RESUMO

Objective Type 2 diabetes mellitus (T2DM) and rheumatoid arthritis (RA) are both complicated by arteriosclerosis, resulting in increased rates of cardiovascular events. No previous studies have compared the index between RA and T2DM. We assessed the vascular endothelial function in early-stage arteriosclerosis for each disease to determine the influential factors and compared the extent to which these two diseases cause vascular endothelial dysfunction. Methods This study is a retrospective study based on medical records. Differences in the reactive hyperemia index (RHI) among the groups and factors affecting the RHI in each group was analyzed. The vascular endothelial function was assessed by measuring the RHI using peripheral arterial tonometry. Patients The study subjects were 114 patients with non-functional thyroid tumors (healthy n=14), T2DM (T2DM n=64), and RA (RA n=36). Results The RHI was 2.29 in the control, 1.85 in the T2DM, and 1.83 in the RA group, with values lower in the T2DM and RA groups than in the control group (p=0.033) but not markedly different between the two disease groups. The RHI distribution (<1.68/1.68 to <2.10/≥2.1) was as follows: control group: 14.3%/28.6%/57.1%; T2DM group: 42.2%/39.1%/18.8%; and RA group: 36.1%/44.4%/19.4% (p=0.031), respectively. A multivariate analysis identified the triglyceride level and dyslipidemia in the control group and the Disease Activity Score in 28 joints with the erythrocyte sedimentation rate and fasting plasma glucose level in the RA group to influence the RHI. Conclusion The vascular endothelial function was impaired in approximately 80% of patients with T2DM and RA, with comparable degrees of impairment between the two diseases. No factors affecting the function were identified in the T2DM group, while the function was more impaired in patients with a higher disease activity in the RA group.


Assuntos
Arteriosclerose/fisiopatologia , Artrite Reumatoide/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Endotélio Vascular/fisiopatologia , Hiperemia/fisiopatologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Manometria/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença
7.
PLoS One ; 14(4): e0214919, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30958851

RESUMO

BACKGROUND: Caffeine is reported to be the most widely used pharmacologically active substance. It causes mental stimulation and increases blood pressure. Acute systolic and diastolic blood pressure response to caffeine attenuates in the course of regular caffeine use; tolerance to cardiovascular responses develops in some people. For some hypertension-prone people coffee ingestion may be harmful, and for others it may be beneficial. The aim of our work was to evaluate the effect of caffeine on postocclusive reactive hyperaemia (PORH), a test of microvascular function, and at the same time to monitor the central effects of caffeine on blood pressure and heart rate. METHODS: Heart rate, arterial pressure, and cutaneous laser-Doppler (LD) flux were monitored in 32 healthy volunteers (aged 25.2 ± 4.3 years) before and after they ingested 200 mg of caffeine. LD flux was measured on a finger at rest and after the release of an 8-minute occlusion of digital arteries above the place of LD flux measurement. All parameters obtained after the ingestion of caffeine were compared to the values obtained before caffeine and to the values obtained after a placebo. RESULTS: We found slightly increased arterial pressure as well as decreased heart rate and resting LD flux (Dunnett's test, p<0.05) after the ingestion of caffeine. Caffeine significantly reduced the PORH response (Dunnett's test, p<0.01). The power of the low-frequency oscillations (0.06-0.15 Hz) of LD flux, representing vascular myogenic activity, increased significantly after the ingestion of caffeine at rest and during the PORH response. A correlation was found between the number of cups of coffee regularly consumed and resting LD flux values (R = 0.492, p = 0.00422), peak LD flux values during PORH (R = 0.458, p = 0.00847), and the PORH area (R = 0.506, p = 0.00313) after caffeine consumption. CONCLUSIONS: From the results, we can conclude that caffeine affects cutaneous microvascular function during rest and during a PORH response, and that it increases blood pressure and decreases heart rate.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Cafeína/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Hiperemia/fisiopatologia , Pele , Adulto , Feminino , Humanos , Masculino , Pele/irrigação sanguínea , Pele/fisiopatologia
8.
Clin Hemorheol Microcirc ; 72(4): 339-351, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31006670

RESUMO

OBJECTIVE: To assess sex-related differences in forearm skin microvascular reactivity to vascular occlusion and cardiovascular health in young healthy women and men. METHODS: 203 young healthy individuals (67 men/136 women) participated in this study. Post-occlusive reactive hyperemia (PORH) in skin microcirculation following 1', 2' and 3' vascular occlusion period was assessed using laser Doppler flowmetry. Anthropometric parameters, body composition, blood pressure, heart rate and biochemical parameters were measured in all participants. Correlations between PORH and measured parameters were determined by using corresponding tests. RESULTS: Women had significantly higher forearm PORH following 1', 2' and 3' vascular occlusion than men. Women had lower body mass index and waist-to-hip ratio, but higher fat mass than men. Men had significantly higher blood pressure and lower heart rate than women. Also, women had lower hemoglobin, urea, creatinine and serum uric acid, but higher HDL cholesterol level than men. PORH was negatively associated with waist-to-hip ratio and systolic blood pressure only in women. CONCLUSIONS: Young healthy women exhibit higher skin microvascular reactivity to vascular occlusion compared to age-matched men. Increased systolic blood pressure or central obesity (waist-to-hip ratio) may pose greater risk to young healthy women than men by adversely affecting peripheral microvascular function.


Assuntos
Antebraço/irrigação sanguínea , Hiperemia/fisiopatologia , Microcirculação/fisiologia , Pele/irrigação sanguínea , Adulto , Feminino , Voluntários Saudáveis , Humanos , Masculino , Caracteres Sexuais , Adulto Jovem
9.
Indian Heart J ; 71(1): 74-79, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31000187

RESUMO

OBJECTIVE: Fractional flow reserve (FFR) using adenosine has been the gold standard in the functional assessment of intermediate coronary stenoses in the catheterization laboratory. We aim to study the correlation of adenosine-free indices such as whole cycle Pd/Pa [the ratio of mean distal coronary pressure (Pd) to the mean pressure observed in the aorta (Pa)], instantaneous wave-free ratio (iFR), and contrast-induced submaximal hyperemia (cFFR) with FFR. METHODS: This multicenter, prospective, observational study included patients with stable angina or acute coronary syndrome (>48 h since onset) with discrete intermediate coronary lesions (40-70% diameter stenosis). All patients underwent assessment of whole cycle Pd/Pa, iFR, cFFR, and FFR. We then evaluated the correlation of these indices with FFR and assessed the diagnostic efficiencies of them against FFR ≤0.80. RESULTS: Of the 103 patients from three different centers, 83 lesions were included for analysis. The correlation coefficient (r value) of whole cycle Pd/Pa, iFR, and cFFR in relation to FFR were +0.84, +0.77, and +0.70 (all p values < 0.001), respectively, and the c-statistic against FFR ≤0.80 were 0.92 (0.86-0.98), 0.89(0.81-0.97), and 0.91 (0.85-0.97) (all p values < 0.001), respectively. The best cut-off values identified by receiver-operator characteristic curve for whole cycle Pd/Pa, iFR, and cFFR were 0.94, 0.90, and 0.88, respectively, for an FFR ≤0.80. By the concept of "adenosine-free zone" (iFR = 0.86-0.93), 59% lesions in this study would not require adenosine. CONCLUSION: All the three adenosine-free indices had good correlation with FFR. There is no difference in the diagnostic accuracies among the indices in functional evaluation of discrete intermediate coronary stenoses. However, further validation is needed before adoption of adenosine-free pressure parameters into clinical practice.


Assuntos
Adenosina/administração & dosagem , Cateterismo Cardíaco/métodos , Estenose Coronária/fisiopatologia , Vasos Coronários/fisiopatologia , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Hiperemia/induzido quimicamente , Angiografia Coronária , Estenose Coronária/diagnóstico , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/efeitos dos fármacos , Feminino , Humanos , Hiperemia/fisiopatologia , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Vasodilatadores/administração & dosagem
11.
Nat Commun ; 10(1): 1110, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30846689

RESUMO

Imaging based on blood flow dynamics is widely used to study sensory processing. Here we investigated the extent to which local neuronal and capillary responses (two-photon microscopy) are correlated to mesoscopic responses detected with fast ultrasound (fUS) and BOLD-fMRI. Using a specialized chronic olfactory bulb preparation, we report that sequential imaging of the same mouse allows quantitative comparison of odour responses, imaged at both microscopic and mesoscopic scales. Under these conditions, functional hyperaemia occurred at the threshold of neuronal activation and fUS-CBV signals could be detected at the level of single voxels with activation maps varying according to blood velocity. Both neuronal and vascular responses increase non-linearly as a function of odour concentration, whereas both microscopic and mesoscopic vascular responses are linearly correlated to local neuronal calcium. These data establish strengths and limits of mesoscopic imaging techniques to report neural activity.


Assuntos
Bulbo Olfatório/diagnóstico por imagem , Bulbo Olfatório/fisiologia , Animais , Velocidade do Fluxo Sanguíneo , Mapeamento Encefálico , Sinalização do Cálcio , Circulação Cerebrovascular , Feminino , Neuroimagem Funcional , Hiperemia/diagnóstico por imagem , Hiperemia/fisiopatologia , Imagem por Ressonância Magnética , Masculino , Camundongos , Camundongos Transgênicos , Odorantes , Bulbo Olfatório/irrigação sanguínea , Olfato/fisiologia , Ultrassonografia
12.
Int J Cardiol ; 285: 93-96, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-30857847

RESUMO

AIM: During invasive fractional flow reserve (FFR) adenosine and nitrates are used to obtain maximal hyperemia. Severe coronary artery calcification (CAC) is associated with impaired vasodilation. We investigated the hyperemic response during FFR in vessels with severe versus mild CAC. METHODS AND RESULTS: We retrospectively selected 236 patients who underwent both CAC scoring and invasive FFR. FFR was performed in 304 vessels with intermediate stenoses. Delta (Δ) FFR, the pressure gradient before the administration of adenosine minus FFR after the administration of adenosine, was used to investigate the hyperemic response. Mean age of the total population was 65 ±â€¯10 years, 65% was male. Median CAC score was 510 (range 0 to 6141). Mean pressure gradient before the administration of adenosine was comparable in vessels with severe versus mild CAC. FFR was more often ≤0.80 in vessels with severe CAC (p = 0.045). Patients with a large Δ FFR were younger (p = 0.05). There was no association between Δ FFR and severity of calcifications. Regression analysis did not demonstrate an association between CAC score and the hyperemic response (p = 0.49). CONCLUSION: We did not find an association between the severity of CAC and the hyperemic response during invasive FFR.


Assuntos
Estenose Coronária/fisiopatologia , Vasos Coronários/fisiopatologia , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Hiperemia/fisiopatologia , Calcificação Vascular/diagnóstico , Vasodilatação/fisiologia , Idoso , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Estenose Coronária/diagnóstico , Vasos Coronários/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Calcificação Vascular/fisiopatologia
13.
NMR Biomed ; 32(5): e4072, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30861224

RESUMO

Aging is associated with impaired endothelium-dependent vasodilation that leads to muscle perfusion impairment and contributes to organ dysfunction. Impaired muscle perfusion may result in inadequate delivery of oxygen and nutrients during and after muscle contraction, leading to muscle damage. The ability to study the relationship between perfusion and muscle damage has been limited using traditional muscle perfusion measures, which are invasive and risky. To overcome this limitation, we optimized a diffusion-weighted MRI sequence and validated an intravoxel incoherent motion (IVIM) analysis based on Monte Carlo simulation to study muscle perfusion impairment with aging during post-exercise hyperemia. Simulation results demonstrated that the bias of IVIM-derived perfusion fraction (fp ) and diffusion of water molecules in extra-vascular tissue (D) ranged from -3.3% to 14% and from -16.5% to 0.002%, respectively, in the optimized experimental condition. The dispersion in fp and D ranged from 3.2% to 9.5% and from 0.9% to 1.1%, respectively. The mid-thigh of the left leg of four younger (21-30 year old) and four older (60-90 year old) healthy females was studied using the optimized protocol at baseline and at seven time increments occurring every 3.25 min following in-magnet dynamic knee extension exercise performed using a MR-compatible ergometer with a workload of 0.4 bar for 2.5 min. After exercise, both fp and D significantly increased in the rectus femoris (active muscle during exercise) but not in adductor magnus (inactive muscle), reflecting the fact that the local increase in perfusion with both groups showed a maximum value in the second post-exercise time-point. A significantly greater increase in perfusion from the baseline (p < 0.05) was observed in the younger group (37 ± 12.05%) compared with the older group (17.57 ± 15.92%) at the first post-exercise measurement. This work establishes a reliable non-invasive method that can be used to study the effects of aging on dynamic changes in muscle perfusion as they relate to important measures of physical function.


Assuntos
Imagem de Difusão por Ressonância Magnética , Exercício/fisiologia , Hiperemia/fisiopatologia , Movimento (Física) , Músculo Esquelético/fisiologia , Perfusão , Coxa da Perna/fisiologia , Adulto , Idoso , Simulação por Computador , Humanos , Processamento de Sinais Assistido por Computador , Razão Sinal-Ruído , Adulto Jovem
14.
Rheumatol Int ; 39(3): 489-495, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30706192

RESUMO

Ocular involvement is present in 50-60% of granulomatosis with polyangiitis (GPA) patients and can affect any part of the ocular globe. The present study describes ophthalmologic manifestations, association with systemic symptoms, disease activity and damage in GPA. A cross-sectional study was conducted including patients with GPA who underwent rheumatologic and ophthalmologic evaluation. Demographics, comorbidities, ophthalmologic symptoms, serologic markers, radiographic studies, disease activity and damage were assessed. Descriptive statistics, correlation, univariable logistic regression analyses, Student's t, Mann-Whitney U, Chi-square and Fisher's exact tests were performed. Fifty patients were included, 60% female, the median age was 56 years, disease duration 72.5 months. Nineteen (38%) patients had ocular manifestations at GPA diagnosis, scleritis being the most frequent; 27 (54%) patients presented ocular involvement during follow-up, repeated scleritis and dacryocystitis being the most common manifestations. Concomitant ophthalmic and sinonasal involvement was present in 12 (24%). Ocular and ENT damage occurred in 58% and 70%, respectively. Epiphora and blurred vision were the most frequent symptoms; scleromalacia and conjunctival hyperemia (27%) the most frequent clinical abnormalities. Ocular involvement at diagnosis was associated with concomitant ocular and sinonasal involvement at follow-up (OR 4.72, 95% CI 1.17-19.01, p = 0.01). Ocular involvement at follow-up was associated with age at GPA diagnosis (OR 0.94, 95% CI 0.90-0.99, p = 0.03), VDI (OR 1.29, 95% CI 1.03-1.61, p = 0.02), and ENT damage (OR 5.27, 95% CI 1.37-20.13, p = 0.01). In GPA, ocular involvement is frequent, therefore, non-ophthalmologist clinicians should be aware of this manifestation to reduce the risk of visual morbidity and organ damage.


Assuntos
Dacriocistite/fisiopatologia , Granulomatose com Poliangiite/fisiopatologia , Doenças Nasais/fisiopatologia , Doenças dos Seios Paranasais/fisiopatologia , Esclerite/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças da Túnica Conjuntiva/etiologia , Doenças da Túnica Conjuntiva/fisiopatologia , Estudos Transversais , Dacriocistite/etiologia , Oftalmopatias/etiologia , Oftalmopatias/fisiopatologia , Feminino , Granulomatose com Poliangiite/complicações , Humanos , Hiperemia/etiologia , Hiperemia/fisiopatologia , Doenças do Aparelho Lacrimal/etiologia , Doenças do Aparelho Lacrimal/fisiopatologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Doenças Nasais/etiologia , Doenças dos Seios Paranasais/etiologia , Esclerite/etiologia , Transtornos da Visão/etiologia , Transtornos da Visão/fisiopatologia , Adulto Jovem
15.
Eur J Appl Physiol ; 119(3): 753-760, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30637458

RESUMO

PURPOSE: The aim of the present study was to investigate why the magnitude of reactive hyperemia (RH) observed by pulse volume amplitude (PVA) after arm occlusion differs greatly among study subjects. METHODS: Healthy subjects (n = 12) in the age range of 22-30 years participated in this study. Vascular reactivity was assessed by measuring the changes in finger PVA simultaneously in the test (occluded arm) and control arm (contralateral non-occluded arm) using two separate Photoplethysmographic sensors. Short-term HRV was computed from simultaneously acquired lead II ECG signal to monitor the changes in cardiac sympathetic nervous activity. RESULTS: The observed coefficient of variation for inter-subject variability in PVA response in test arm during second minute of RH was 115.3%. In the control arm, significantly reduced PVA was observed during the period of occlusion as well as RH. This observation was corroborated by simultaneously acquired short-term HRV which showed a significant rise in total power (p value < 0.005) and low-frequency (LF) power (p value < 0.05) during release of occlusion when compared to the baseline. A significant positive correlation (Spearman r = 0.33; p = 0.02) was observed between % change in PVA in the control arm and in the test arm for first 3 min of RH. CONCLUSIONS: Sympathetic activation possibly plays an important role in mediating the inter-subject variability of vascular responses during reactive hyperemia which warrants simultaneous recording of both the test and the control arm responses during RH to accurately assess endothelial function.


Assuntos
Endotélio Vascular/fisiopatologia , Dedos/irrigação sanguínea , Hiperemia/fisiopatologia , Fotopletismografia , Adulto , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fotopletismografia/métodos , Adulto Jovem
16.
Wound Repair Regen ; 27(3): 225-234, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30667138

RESUMO

Frequent repositioning is important to prevent pressure ulcer (PU) development, by relieving pressure and recovering damages on skin areas induced by repetitive loading. Although repositioning is the gold standard to prevent PU, there is currently no strategy for determining tissue condition under preventive approaches. In this study, the peak reactive hyperemia (RH) trends and ultrasonographic (US) features are compared with the tissue condition under histopathological examination to determine the potential use of these features in determining the tissue condition noninvasively. Twenty-one male Sprague-Dawley rats (seven per group), with body weight of 385-485 g, were categorized into three groups and subjected to different recovery times, each with three repetitive loading cycles at skin tissues above of right trochanter area. The first, second, and third groups were subjected to short (3 minutes), moderate (10 minutes), and prolonged (40 minutes) recovery, respectively, while applying fixed loading time and pressure (10 minutes and 50 mmHg, respectively), to provide different degree of recovery and tissue conditions (tissue damage and tissue recovery). Peak RH was measured in the three cycles to determine RH trend (increasing, decreasing, and inconsistent). All rat tissues were evaluated using ultrasound at pre- and post-experiment and rated by two raters to categorize the severity of tissue changes (no, mild, moderate, and severe). The tissue condition was also evaluated using histopathological examination to distinguish between normal and abnormal tissues. Most of the samples with increasing RH trend is related to abnormal tissue (71%); while inconsistent RH trends is more related to normal tissue (82%). There is no relationship between the tissue conditions evaluated under ultrasonographic and histopathological examination. Peak RH trend over repetitive loading may serve as a new feature for determining the tissue condition that leading to pressure ulcer.


Assuntos
Hiperemia/fisiopatologia , Lesão por Pressão/prevenção & controle , Pressão , Fluxo Sanguíneo Regional/fisiologia , Pele/irrigação sanguínea , Ultrassonografia , Suporte de Carga , Cicatrização/fisiologia , Animais , Modelos Animais de Doenças , Técnicas de Imagem por Elasticidade , Masculino , Pressão/efeitos adversos , Lesão por Pressão/patologia , Ratos , Ratos Sprague-Dawley , Pele/diagnóstico por imagem , Pele/lesões
17.
Microvasc Res ; 123: 68-73, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30611746

RESUMO

BACKGROUND: The impairment of endothelial function in type 1 diabetes mellitus (DM1) is considered as the basis of microvascular complications. In DM1 patients autoimmune thyroiditis is a frequent comorbidity which may be responsible for further deterioration of microcirculation function. In studies investigating the relationship between cardiovascular risk factors and microvascular function, skin microcirculation is widely used. The aim of our study was to evaluate the impact of coexisting autoimmune thyroiditis on skin microcirculation in children with type I diabetes mellitus. SUBJECTS: The study group consisted of 25 pediatric DM1 patients, 25 pediatric patients with type 1 diabetes and autoimmune thyroiditis (DM1 + AIT) and 29 control subjects matched for age and gender. The DM1 and DM1 + AIT patients were also matched for age at onset of DM and diabetes duration. METHODS: Performed capillaroscopy studies employed non-selective stimuli such as post-occlusive reactive hyperemia (PORH) and venous occlusion (VO) tests. The relative area covered by capillaries (coverage) and the distance between capillaries were assessed. These measurements were performed before tests as well as after PORH and VO. RESULTS: Coverage at baseline, after PORH and VO and distance after VO differ significantly between control subjects and the group DM1 + AIT. The coverage at baseline, after PORH and VO were significantly smaller in DM1 + AIT compared with the control group. Post-hoc analysis after controlling for lipids levels showed that differences between the DM1 + AIT and control group were remained only for coverage at baseline and after VO. Significant differences between DM1 + AIT and DM1 and control group for coverage after VO were also presented. CONCLUSIONS: Coexisting autoimmune thyroiditis significantly deteriorates skin microcirculation function in pediatric non-complicated type 1 diabetic patients. This process is independent of patient age, diabetes duration and age of diabetes onset.


Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Angiopatias Diabéticas/fisiopatologia , Microcirculação , Microvasos/fisiopatologia , Pele/irrigação sanguínea , Tireoidite Autoimune/fisiopatologia , Adolescente , Fatores Etários , Estudos de Casos e Controles , Criança , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/diagnóstico por imagem , Angiopatias Diabéticas/diagnóstico por imagem , Angiopatias Diabéticas/etiologia , Feminino , Humanos , Hiperemia/fisiopatologia , Masculino , Angioscopia Microscópica , Microvasos/diagnóstico por imagem , Oclusão Terapêutica , Tireoidite Autoimune/complicações , Tireoidite Autoimune/diagnóstico por imagem
18.
PLoS One ; 14(1): e0208612, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30616240

RESUMO

OBJECTIVE: The aim was threefold: 1) expound the independent physiological parameters that drive FFR, 2) elucidate contradictory conclusions between fractional flow reserve (FFR) and coronary flow reserve (CFR), and 3) highlight the need of both FFR and CFR in clinical decision making. Simple explicit theoretical models were supported by coronary data analyzed retrospectively. METHODOLOGY: FFR was expressed as a function of pressure loss coefficient, aortic pressure and hyperemic coronary microvascular resistance. The FFR-CFR relationship was also demonstrated mathematically and was shown to be exclusively dependent upon the coronary microvascular resistances. The equations were validated in a first series of 199 lesions whose pressures and distal velocities were monitored. A second dataset of 75 lesions with pre- and post-PCI measures of FFR and CFR was also analyzed to investigate the clinical impact of our hemodynamic reasoning. RESULTS: Hyperemic coronary microvascular resistance and pressure loss coefficient had comparable impacts (45% and 49%) on FFR. There was a good concordance (y = 0.96 x - 0.02, r2 = 0.97) between measured CFR and CFR predicted by FFR and coronary resistances. In patients with CFR < 2 and CFR/FFR ≥ 2, post-PCI CFR was significantly >2 (p < 0.001), whereas it was not (p = 0.94) in patients with CFR < 2 and CFR/FFR < 2. CONCLUSION: The FFR behavior and FFR-CFR relationship are predictable from basic hemodynamics. Conflicting conclusions between FFR and CFR are explained from coronary vascular resistances. As confirmed by our results, FFR and CFR are complementary; they could jointly contribute to better PCI guidance through the CFR-to-FFR ratio in patients with coronary artery disease.


Assuntos
Circulação Coronária/fisiologia , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Microvasos/fisiopatologia , Intervenção Coronária Percutânea , Resistência Vascular/fisiologia , Biomarcadores/metabolismo , Hemodinâmica/fisiologia , Humanos , Hiperemia/fisiopatologia , Isquemia Miocárdica/fisiopatologia , Prognóstico , Curva ROC
19.
Perit Dial Int ; 39(2): 155-162, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30661003

RESUMO

BACKGROUND: Peritoneal effluent from peritoneal dialysis (PD) patients contains proteins, mainly transported from the circulation through large pores in the venular part of the peritoneal microvessels. Hydrostatic convection is the major driver for peritoneal protein transport, although in PD there is additional diffusion. Consequently, venous pressure may have a role in peritoneal protein transport. The aim of the study was to investigate the importance of venous congestion on the magnitude of peritoneal protein clearance in incident PD patients using non-invasive measurements. METHODS: A total of 316 adult PD patients, on PD for 8 - 12 weeks and collecting 24-hour urine and dialysate for total protein determination, underwent standard peritoneal equilibration testing (PET) along with measurement of N terminal pro-brain natriuretic peptide (NT-proBNP) and C-reactive protein (CRP), multifrequency bioimpedance analysis, and a transthoracic echocardiogram. RESULTS: Statistically significant univariate relationships for peritoneal protein clearance with a Spearman correlation coefficient > 0.25 were present for 4-hour dialysate/plasma (D/P) creatinine, NT-proBNP, extracellular/total body water, extracellular water excess, left ventricular mass, and right atrial area. Negative correlations were found with serum total protein and residual renal function. On multivariate analysis, logNTproBNP (ß 0.11, p = 0.007) and right atrial area (ß 0.01, p = 0.03) were significant independent predictors of peritoneal protein clearance. CONCLUSION: Indicators of venous congestion showed the most important relationships with peritoneal protein clearance. These indicators have not been assessed in previous studies on the presence or absence of relationships between peritoneal protein clearance and mortality.


Assuntos
Hiperemia/metabolismo , Hiperemia/fisiopatologia , Peritônio/metabolismo , Transporte Proteico , Proteínas/metabolismo , Adulto , Humanos , Microvasos
20.
Appl Physiol Nutr Metab ; 44(4): 425-433, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30257099

RESUMO

This study examined if the degree of aerobic training protects against the lower limb vascular dysfunction associated with a prolonged sitting bout. Ten young, aerobically trained (AT) and 10 young, untrained (UT) individuals completed a prolonged (3 h) sitting bout. Leg vascular function was measured prior to and at 1.5 and 3 h into the prolonged sitting bout using the passive leg movement (PLM) technique. PLM-induced hyperemia was significantly reduced from baseline at 1.5 and 3 h into the prolonged sitting bout in both groups when evaluated as peak change in leg blood flow from baseline (Δ LBF) (UT: 956 ± 140, 586 ± 80, and 599 ± 96 mL·min-1 at baseline, 1.5 h, and 3 h, respectively; AT: 955 ± 183, 789 ± 193, and 712 ± 131 mL·min-1 at baseline, 1.5 h, and 3 h, respectively) and LBF area under the curve (UT: 283 ± 73, 134 ± 31, and 164 ± 42 mL·min-1 at baseline, 1.5 h, and 3 h, respectively; AT: 336 ± 86, 242 ± 86, and 245 ± 73 mL·min-1 at baseline, 1.5 h, and 3 h, respectively), but no significant differences between groups were revealed. No significant correlations were observed when examining the relationship between maximal oxygen uptake (relative and absolute) and reductions in leg vascular function at 1.5 and 3 h into the prolonged sitting bout. This study revealed that aerobic training did not provide a protective effect against prolonged sitting-induced lower limb vascular dysfunction and further highlights the importance of reducing excessive sitting in all populations.


Assuntos
Artéria Femoral/fisiopatologia , Hiperemia/fisiopatologia , Extremidade Inferior/irrigação sanguínea , Aptidão Física , Comportamento Sedentário , Postura Sentada , Adolescente , Adulto , Pressão Arterial , Velocidade do Fluxo Sanguíneo , Feminino , Artéria Femoral/diagnóstico por imagem , Frequência Cardíaca , Humanos , Hiperemia/diagnóstico por imagem , Masculino , Consumo de Oxigênio , Fluxo Sanguíneo Regional , Descanso , Fatores de Risco , Fatores de Tempo , Ultrassonografia Doppler , Adulto Jovem
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