Search results for "Blood flow"

2019

The cytokine interleukin-1 (IL-1) is a key contributor to neuroinflammation and brain injury, yet mechanisms by which IL-1 triggers neuronal injury remain unknown. Here we induced conditional deletion of IL-1R1 in brain endothelial cells, neurons and blood cells to assess site-specific IL-1 actions in a model of cerebral ischaemia in mice. Tamoxifen treatment of IL-1R1 floxed (fl/fl) mice crossed with mice expressing tamoxifen-inducible Cre-recombinase under the Slco1c1 promoter resulted in brain endothelium-specific deletion of IL-1R1 and a significant decrease in infarct size (29%), blood-brain barrier (BBB) breakdown (53%) and neurological deficit (40%) compared to vehicle-treated or con…

Interaction of calcitonin gene related peptide (CGRP) and substance P (SP) in human skin.

2016

Calcitonin gene related peptide (CGRP) and substance P (SP) are neuropeptides that are simultaneously released from nociceptive C-fibers. CGRP is a potent vasodilator, inducing a long-lasting increase in superficial skin blood flow, whereas SP induces only a brief vasodilation but a significant plasma extravasation. CGRP and SP may play important roles in the pathophysiology of various pain states but little is known about their interaction. Different concentrations of SP (ranging from 10-5M to 10-9M) were applied to the volar forearm of 24 healthy subjects via dermal microdialysis. SP was applied either alone or in combination with CGRP10-9M and CGRP 10-6M. As expected, SP induced a transi…

Can mild cognitive impairment be stabilized by showering brain mitochondria with laser photons?

2019

There is now substantial evidence that cerebral blood flow (CBF) declines with age. From age 20 to 60, CBF is estimated to dip about 16% and continues to drop at a rate of 0.4%/year. This CBF dip will slowly reduce oxygen/glucose delivery to brain thus lowering ATP energy production needed by brain cells to perform normal activities. Reduced ATP production from mitochondrial loss or damage in the wear-and-tear of aging worsens when vascular risk factors (VRF) to Alzheimer's disease develop that can accelerate both age-decline CBF and mitochondrial deficiency to a level where mild cognitive impairment (MCI) develops. To date, no pharmacological or any other treatment has been successful in r…

Leisure-time physical activity and artery lumen diameters: A monozygotic co-twin control study

2010

Exercise is thought to increase the diameter of the conduit arteries supplying the muscles involved. We studied the effects of a physically active vs inactive lifestyle on artery diameters in monozygotic (MZ) twin pairs discordant over 30 years for leisure-time physical activity habits. In a population-based co-twin control study design, six middle-aged (50-65 years) same-sex MZ twin pairs with long-term discordance for physical activity were comprehensively identified from the Finnish Twin Cohort (TWINACTIVE study). Discordance was initially defined in 1975 and the same co-twin remained significantly more active during the 32-year follow-up. The main outcomes were arterial lumen diameters …

Perfusion MRI in normal and abnormal pituitary gland. A preliminary study.

1997

Perfusion MRI (magnetic resonance imaging) of the pituitary gland was performed in 20 healthy volunteers and 63 patients with various lesions involving the pituitary gland. All patients underwent sequential contrast-enhanced MRI using spoiled gradient recalled sequences with high temporal resolution (7 seconds). Four pituitary areas (pituitary stalk, posterior lobe, postero-superior, and antero-inferior adenohypophysis) were tested with a selected region of interest. Maximal contrast percentual variation was calculated. The timing of enhancement in normal patients matched perfectly with normal pituitary vascularization. Abnormal timing in pathological condition was investigated.

Clinical-anamnestic and instrumental data in outpatients suffering from venous disease

1995

The authors studied 200 consecutive outpatients with symptoms due to venous disease of the lower limbs. All the patients underwent anamnestic, clinical and instrumental evaluation (c.w. Doppler velocimetry and strain-gauge plethysmography). The results of this study showed that some anamnestic and clinical data are significantly related to venous disease detected by instrumental techniques. The superficial and deep vein hypertension were, instead, correlated to oral contraceptive use.

Effect of epidural anesthesia on colorectal anastomosis: a tonometric assessment.

1997

PURPOSE: Epidural anesthesia is believed to benefit colorectal anastomotic blood flow because of the sympathetic blockade it produces. Our purpose is to measure with tonometry the effect of epidural anesthesia on colorectal anastomotic oxygenation. PATIENTS AND METHODS: Fifteen patients operated on for rectal cancer (radical anterior resection) were monitored postoperatively using tonometers placed in the stomach (celiac trunk), transverse colon (superior mesenteric artery), and the anastomotic area during the operation. An epidural catheter was placed at L1-2, and on the first postoperative day, 8 ml of bupivacaine (0.25 percent) was administered. The anesthetic effect extended up to T-4. …

Impact of insulin on microvascular blood flow and endothelial cell function in the postprandial state in patients with Type 1 diabetes.

2005

The aim of the present study was to investigate postprandial microvascular blood flow following a standardized test meal in nondiabetic subjects and in patients with Type 1 diabetes after regular insulin or insulin lispro. In this open-label, randomised cross-over study, 20 nondiabetic participants and 20 patients with Type 1 diabetes were enrolled. To valuate the postprandial time course of skin microvascular blood flow, laser Doppler flux (LDF) readings were obtained at baseline and every 30 min following a standardized test meal. Furthermore, the microvascular response to acetylcholine (Ach) was measured, and blood was collected for the measurement of serum insulin and blood glucose leve…

Microvascular skin blood flow following the ingestion of 75 g glucose in healthy individuals.

2009

It is expected that microvascular blood flow might be affected by blood glucose, blood insulin and C-peptide levels. In our investigation skin microvascular blood flow (LDF) was measured using laser doppler fluxometry at skin temperatures of 37 degrees C and 44 degrees C during a 75 g oral glucose load (OGT) or water in ten healthy volunteers (6 male, 4 female, age: 28.1+/-4.0) who had fasted overnight. The transcutaneous oxygen tension (tcPO2) was measured using a transcutaneous oxygen electrode at a temperature of 44 degrees C. The microvascular response to acetylcholine was investigated before the start of the ingestion period and after 30 minutes. In addition, the capillary blood cell v…

Influence of glucose control and improvement of insulin resistance on microvascular blood flow and endothelial function in patients with diabetes mel…

2005

The study was performed to investigate the effect of improving metabolic control with pioglitazone in comparison to glimepiride on microvascular function in patients with diabetes mellitus type 2.A total of 179 patients were recruited and randomly assigned to one treatment group. Metabolic control (HbA1c), insulin resistance (HOMA index), and microvascular function (laser Doppler fluxmetry) were observed at baseline and after 3 and 6 months.HbA1c improved in both treatment arms (pioglitazone: 7.52 +/- 0.85% to 6.71 +/- 0.89%, p.0001; glimepiride: 7.44 +/- 0.89% to 6.83 +/- 0.85%, p.0001). Insulin-resistance decreased significantly in the pioglitazone group (6.15 +/- 4.05 to 3.85 +/- 1.92, p…