Central and Peripheral Circulation after an Isotonic Volume Expansion with Saline in Human Subjects

2015 ◽  
pp. 88-92 ◽  
Author(s):  
J. Bahlmann ◽  
U. M�ller-Barth�l ◽  
W. Hubrich ◽  
J. Brod
Keyword(s):  
Volume Expansion ◽  
Human Subjects ◽  
Peripheral Circulation

AN EFFECT OF REDUCED BAROMETRIC PRESSURE ON THE PERIPHERAL CIRCULATION

1957 ◽  
Vol 35 (10) ◽  
pp. 777-783
Author(s):  
F. Girling ◽  
F. A. Sunahara
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Forearm Blood Flow ◽  
Human Subjects ◽  
Arterial Oxygen Saturation ◽  
Barometric Pressure ◽  
Peripheral Circulation ◽  
Arterial Oxygen ◽  
Blood Flows ◽  
The Past

Several groups of investigators have noted in the past that exposure to a reduced barometric pressure results in a decrease in peripheral blood flow.In the present study human subjects were exposed to a pressure of 225 mm. Hg with maintenace of arterial oxygen saturation, and forearm and hand blood flows were measured plethysmographically. Forearm blood flow was not affected by the exposure whereas hand blood flow was reduced in all subjects. Blood pressure and heart rate were also measured and showed no change during the experiment.

FREE AND SOLVOLYSABLE DEHYDROEPIANDROSTERONE AND ANDROSTERONE IN BLOOD OF MAMMALS UNDER PHYSIOLOGICAL CONDITIONS AND FOLLOWING ADMINISTRATION OF DEHYDROEPIANDROSTERONE

1977 ◽  
Vol 85 (1) ◽  
pp. 126-133 ◽  
Author(s):  
T. Fehér ◽  
L. Bodrogi ◽  
K. G. Fehér ◽  
E. Poteczin ◽  
I. S. Kölcsey
Keyword(s):  
Human Plasma ◽  
Chromatographic Method ◽  
Human Subjects ◽  
Peripheral Circulation ◽  
Plasma Samples ◽  
Dehydroepiandrosterone Sulphate ◽  
Pronounced Increase ◽  
Physiological Conditions ◽  
Gas Chromatographic Method

ABSTRACT A gas chromatographic method has been employed for the determination of dehydroepiandrosterone (D), androsterone (A), dehydroepiandrosterone sulphate (DS) and androsterone sulphate (AS) in the peripheral blood of human subjects and in various mammals under physiological conditions and after the administration of D or DS. Unconjugated D has been isolated and the resting level determined in the rat, rabbit, dog, sheep, pig and cow, while DS was detectable in the peripheral circulation of the rat, dog and pig. Unconjugated A was present in blood of the rodents and domestic ungulates studied, while the parent sulphate could be demonstrated only in rat, dog, pig and cow. The plasma of lower mammals contained D in higher (0.8–10.9 μg/100 ml), and DS, if any, in lower level (1.5–5.7 μg/100 ml) than the human plasma samples (0.1–2.7 and 86–308 μg/100 ml, respectively). There was a more pronounced increase in D and A than in the DS and AS level in the rat and dog following administration of D. On the contrary, exogenous D hardly affected unconjugated D and appreciably enhanced the DS level in human plasma. The conclusion drawn for human subjects, that D is the metabolically active and DS the reserve hormone, does not seem to be valid for all the animals here studied.

Dissociation between circulating concentrations of immunoreactive growth hormone releasing factor and growth hormone in normal human subjects

1987 ◽  
Vol 72 (2) ◽  
pp. 181-185 ◽  
Author(s):  
A. M. Sopwith ◽  
Elizabeth S. Penny ◽  
N. Lytras ◽  
G. M. Besser ◽  
Lesley H. Rees
Keyword(s):  
Growth Hormone ◽  
Human Growth Hormone ◽  
Human Subjects ◽  
Hormone Secretion ◽  
Growth Hormone Secretion ◽  
Human Growth ◽  
Normal Subjects ◽  
Peripheral Circulation ◽  
Growth Hormone Releasing Factor ◽  
Specific Radioimmunoassay

1. Using a highly specific radioimmunoassay we have measured immunoreactive human growth hormone releasing factor (ir-hGRF) concentrations in the peripheral circulation of a total of 12 normal subjects. 2. Neither insulin-induced hypoglycaemia, intravenous arginine nor oral carbohydrate caused any change in venous plasma ir-hGRF concentrations, despite the expected stimulation and suppression respectively of growth hormone secretion. 3. Growth hormone secretion was not increased by oral fat or protein but each of these two foods stimulated ir-hGRF concentrations two- to fourfold. 4. Spontaneous pulses of growth hormone secretion on control days were unaccompanied by any increase in plasma ir-hGRF. 5. The dissociation between peripheral circulating ir-hGRF and growth hormone responses demonstrated under different circumstances suggests that an important source of human growth hormone releasing factor lies outside the hypothalamus and that secretion from this source is unconnected with the normal control of pituitary growth hormone secretion.

Osmoregulatory inhibition of thermally induced cutaneous vasodilation in passively heated humans

1997 ◽  
Vol 273 (1) ◽  
pp. R197-R204 ◽  
Author(s):  
A. Takamata ◽  
K. Nagashima ◽  
H. Nose ◽  
T. Morimoto
Keyword(s):  
Volume Expansion ◽  
Room Temperature ◽  
Human Subjects ◽  
Plasma Osmolality ◽  
Passive Heating ◽  
Plasma Volume Expansion ◽  
Thermally Induced ◽  
Time Control ◽  
Cutaneous Vasodilation ◽  
Vasodilatory Response

We examined the effect of increased plasma osmolality (P(osm)) on cutaneous vasodilatory response to increased esophageal temperature (T(es)) in passively heated human subjects (n = 6). To modify P(osm), subjects were infused with 0.9, 2, or 3% NaCl infusions (Inf) for 90 min on separate days. Infusion rates were 0.2, 0.15, and 0.125 ml.min-1.kg body wt-1 for 0.9, 2, and 3% Inf, respectively, which produced relatively similar plasma volume expansion. Thirty minutes after the end of infusion, subjects immersed their lower legs in a water bath at 42 degrees C (room temperature 28 degrees C) for 60 min after 10 min of preheating control measurements. Passive heating without infusion (NI) served as time control to account for the effect of volume expansion. P(osm) (mosmol/kgH2O) values at the onset of passive heating were 289.9 +/- 1.4, 292.1 +/- 0.6, 298.7 +/- 0.7, and 305.6 +/- 0.6 after NI, 0.9% Inf, 2% Inf, and 3% Inf, respectively. The increases in T(es) (delta T(es)) at equilibrium during passive heating (mean delta T(es) during 55-60 min) were 0.47 +/- 0.08, 0.59 +/- 0.08, 0.85 +/- 0.13, and 1.09 +/- 0.12 degrees C after NI, 0.9% Inf, 2% Inf, and 3% Inf, respectively, which indicates that T(es) at equilibrium increased linearly as P(osm) increased. delta T(es) required to elicit cutaneous vasodilation (delta T(es) threshold for cutaneous vasodilation) also increased linearly as P(osm) increased as well as the delta T(es) threshold for sweating. The calculated increases in these thresholds per unit rise in P(osm) from regression analysis were 0.044 degree C for the cutaneous vasodilation and 0.034 degree C for sweating. Thus the delta T(es) thresholds for cutaneous vasodilation and sweating are shifted to higher delta T(es) along with the increase in P(osm), and these shifts resulted in the higher increase in T(es) during passive heating.

AN EFFECT OF REDUCED BAROMETRIC PRESSURE ON THE PERIPHERAL CIRCULATION

1957 ◽  
Vol 35 (1) ◽  
pp. 777-783
Author(s):  
F. Girling ◽  
F. A. Sunahara
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Forearm Blood Flow ◽  
Human Subjects ◽  
Arterial Oxygen Saturation ◽  
Barometric Pressure ◽  
Peripheral Circulation ◽  
Arterial Oxygen ◽  
Blood Flows ◽  
The Past

Several groups of investigators have noted in the past that exposure to a reduced barometric pressure results in a decrease in peripheral blood flow.In the present study human subjects were exposed to a pressure of 225 mm. Hg with maintenace of arterial oxygen saturation, and forearm and hand blood flows were measured plethysmographically. Forearm blood flow was not affected by the exposure whereas hand blood flow was reduced in all subjects. Blood pressure and heart rate were also measured and showed no change during the experiment.

Radiation Damage Studies with the HVEM

1972 ◽  
Vol 30 ◽  
pp. 680-681
Author(s):  
J. J. Laidler ◽  
B. Mastel
Keyword(s):  
Radiation Damage ◽  
Stainless Steels ◽  
Volume Expansion ◽  
Austenitic Stainless Steels ◽  
Test Facility ◽  
Fast Breeder Reactors ◽  
Breeder Reactors ◽  
Under Construction ◽  
Development Laboratory ◽  
Insight Into

One of the major materials problems encountered in the development of fast breeder reactors for commercial power generation is the phenomenon of swelling in core structural components and fuel cladding. This volume expansion, which is due to the retention of lattice vacancies by agglomeration into large polyhedral clusters (voids), may amount to ten percent or greater at goal fluences in some austenitic stainless steels. From a design standpoint, this is an undesirable situation, and it is necessary to obtain experimental confirmation that such excessive volume expansion will not occur in materials selected for core applications in the Fast Flux Test Facility, the prototypic LMFBR now under construction at the Hanford Engineering Development Laboratory (HEDL). The HEDL JEM-1000 1 MeV electron microscope is being used to provide an insight into trends of radiation damage accumulation in stainless steels, since it is possible to produce atom displacements at an accelerated rate with 1 MeV electrons, while the specimen is under continuous observation.

Elevated level of circulatory sTLT1 induces inflammation through SYK/MEK/ERK signalling in coronary artery disease

2019 ◽  
Vol 133 (22) ◽  
pp. 2283-2299
Author(s):  
Apabrita Ayan Das ◽  
Devasmita Chakravarty ◽  
Debmalya Bhunia ◽  
Surajit Ghosh ◽  
Prakash C. Mandal ◽  
...  
Keyword(s):  
Risk Factors ◽  
Coronary Artery Disease ◽  
Coronary Artery ◽  
Chronic Inflammation ◽  
Ex Vivo ◽  
Human Subjects ◽  
Critical Role ◽  
Atherosclerotic Cardiovascular Disease ◽  
Tnf Α ◽  
Artery Disease

Abstract The role of inflammation in all phases of atherosclerotic process is well established and soluble TREM-like transcript 1 (sTLT1) is reported to be associated with chronic inflammation. Yet, no information is available about the involvement of sTLT1 in atherosclerotic cardiovascular disease. Present study was undertaken to determine the pathophysiological significance of sTLT1 in atherosclerosis by employing an observational study on human subjects (n=117) followed by experiments in human macrophages and atherosclerotic apolipoprotein E (apoE)−/− mice. Plasma level of sTLT1 was found to be significantly (P<0.05) higher in clinical (2342 ± 184 pg/ml) and subclinical cases (1773 ± 118 pg/ml) than healthy controls (461 ± 57 pg/ml). Moreover, statistical analyses further indicated that sTLT1 was not only associated with common risk factors for Coronary Artery Disease (CAD) in both clinical and subclinical groups but also strongly correlated with disease severity. Ex vivo studies on macrophages showed that sTLT1 interacts with Fcɣ receptor I (FcɣRI) to activate spleen tyrosine kinase (SYK)-mediated downstream MAP kinase signalling cascade to activate nuclear factor-κ B (NF-kB). Activation of NF-kB induces secretion of tumour necrosis factor-α (TNF-α) from macrophage cells that plays pivotal role in governing the persistence of chronic inflammation. Atherosclerotic apoE−/− mice also showed high levels of sTLT1 and TNF-α in nearly occluded aortic stage indicating the contribution of sTLT1 in inflammation. Our results clearly demonstrate that sTLT1 is clinically related to the risk factors of CAD. We also showed that binding of sTLT1 with macrophage membrane receptor, FcɣR1 initiates inflammatory signals in macrophages suggesting its critical role in thrombus development and atherosclerosis.

Intradermal challenge with interleukin-8 causes tissue oedema and neutrophil accumulation in atopic and non-atopic human subjects

1996 ◽  
Vol 26 (12) ◽  
pp. 1371-1379 ◽  
Author(s):  
J. Douglass ◽  
D. Dhami ◽  
M. Bulpitt ◽  
I. J. Lindley ◽  
J. Shute ◽  
...  
Keyword(s):  
Human Subjects ◽  
Interleukin 8 ◽  
Neutrophil Accumulation ◽  
Tissue Oedema

Research Recommendations for Applying Vitamin A-Labelled Isotope Dilution Techniques to Improve Human Vitamin A Nutrition

2014 ◽  
Vol 84 (Supplement 1) ◽  
pp. 52-59 ◽  
Author(s):  
Sherry A. Tanumihardjo ◽  
Anura V. Kurpad ◽  
Janet R. Hunt
Keyword(s):  
Public Health ◽  
Vitamin A ◽  
Vitamin A Deficiency ◽  
Human Subjects ◽  
The Body ◽  
Pool Size ◽  
Serum Retinol ◽  
Vitamin A Status ◽  
Status Assessment ◽  
Total Body

The current use of serum retinol concentrations as a measurement of subclinical vitamin A deficiency is unsatisfactory for many reasons. The best technique available for vitamin A status assessment in humans is the measurement of total body pool size. Pool size is measured by the administration of retinol labelled with stable isotopes of carbon or hydrogen that are safe for human subjects, with subsequent measurement of the dilution of the labelled retinol within the body pool. However, the isotope techniques are time-consuming, technically challenging, and relatively expensive. There is also a need to assess different types of tracers and doses, and to establish clear guidelines for the use and interpretation of this method in different populations. Field-friendly improvements are desirable to encourage the application of this technique in developing countries where the need is greatest for monitoring the risk of vitamin A deficiency, the effectiveness of public health interventions, and the potential of hypervitaminosis due to combined supplement and fortification programs. These techniques should be applied to validate other less technical methods of assessing vitamin A deficiency. Another area of public health relevance for this technique is to understand the bioconversion of β-carotene to vitamin A, and its relation to existing vitamin A status, for future dietary diversification programs.

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