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At least 73 records · Page 4Linked to original sources

PubMed1996

A revised cold water immersion test for assessing peripheral circulatory function.

To improve the conventional cold water immersion test for assessing peripheral circulatory function, the immersed area of the hand was changed in this study. Twenty-seven healthy medical students with a mean age of 24 years participated in the study. The cold water immersion tests were carried out using two methods (in 5 degree C water for 1 min), in which the immersed area was up to the metacarpophalangeal (MP) joints (hereafter, MP-method) which is a new method, or to the wrist (hereafter, W-method) which is a conventional method. The recovery of skin temperature, vibratory perception threshold and complaints of finger pain were determined during cold immersion tests with the two methods. The mean skin temperature for the MP-method after immersion recovered more quickly than that for the W-method. However, the time courses of recovering were parallel for the two methods. Significant differences were noted at 3 min, 5 min and 10 min after cessation of immersion. There was a significant positive correlation in the recovery rates at 5 min after immersion between the two methods (correlation coefficient = 0.65, p < 0.01). The mean vibratory thresholds for the W-method were higher than those for the MP-method, and the difference was significant (p < 0.01). All subjects preferred the MP-method to the W-method because there was less finger pain. These results indicate that the MP-method, immersion up to the MP joint of a hand, for assessing peripheral circulatory function is better than the W-method.

Adult↗

PubMed2001

Effect of regular winter swimming on the activity of the sympathoadrenal system before and after a single cold water immersion.

This study deals with the adaptation of the sympathoadrenal responses to an acute cold water immersion in ordinary winter swimmers. Hormonal responses were determined at the beginning of the winter swimming period in the autumn and after regular swimming for one and three months. Water temperature in the river was 10 degrees C at the beginning and 4 degrees C after one and three months. The mean duration of the test immersion was 36 s. Plasma catecholamine levels determined before the test immersion decreased with the winter swimming period for one month (NA, p < 0.001, A, p < 0.01). The test immersion significantly increased noradrenaline levels (p < 0.001). Plasma adrenaline and serum cortisol levels were increased or decreased by the immersion. After 1 month's swimming the test immersion to 4 degrees C increased noradrenaline to a similar level than the immersion to 10 degrees C at the beginning. Regularly practiced winter swimming for three months led to diminished catecholamine levels measured immediately after the test immersion (p < 0.01). The results suggest that cold adaptation induced by winter swimming attenuates the catecholamine responses to cold water. Adrenaline responses are also affected by its level prior to the immersion.

Adaptation, Physiological↗

PubMedDate not supplied

[The influence of water immersion on the course of first stage of parturition in primiparous women].

THE AIM: To find whether, and if so to which degree, water immersion may influence the duration of the first stage of labour and to what extent progression of delivery depends on the timing of immersion. MATERIAL AND METHODS: The analysis was conducted for 205 deliveries including 100 in the control group. The following parameters were measured: 1. degree in gaping of the external opening of the uterine cervix during immersion in water; 2. time elapsed between the end of immersion and full gaping of the uterine cervix, 3. course of uterine contraction activity during and after the immersion in water. RESULTS: It was observed that the immersion in water applied to primiparae at any stage of labour, beginning from the 2-cm gaping of the external opening of the uterine cervix, decreased significantly the duration of parturition in comparison to those delivered in a traditional way. In no case the water immersion caused disturbances in the contraction activity of the uterus, instead, it raised both the amplitude and frequency of uterine contractions in a degree proportional to the uterine cervix gaping. CONCLUSIONS: In the authors' opinion the optimal timing for the application of water immersion in the primiparae is determined by a 3-cm gaping of the uterine cervix. An earlier bath at the 2-cm uterine cervix gaping also accelerated the labour but required either repeating of the immersion or a correction of weakened uterine contraction activity by oxytocin.

Adult↗

PubMed1991

Tonic changes in alpha power during immersion of the hand in cold water.

Phasic event-related desynchronization (ERD) of alpha activity briefly follows many types of stimulation. In order to define EEG changes resulting from longer stimulation. EEG records were made before and during hand immersion into cool and painfully cold water (cold pressor). Five minutes of 13-lead EEG records were obtained from 14 subjects for each condition. EEG frequency analysis was performed on artifact-free epochs from 60 to 240 sec following immersion. Following an initial phasic decrease in alpha power during cold water immersion, there was an augmentation of alpha power (8-12 Hz) in bilateral frontal and posterior electrodes. This augmentation was largely the result of an increase in the low alpha band (8-10 Hz). Alpha power at both central electrodes C3 and C4 changed little during cold water immersion. Cool water immersion produced less alpha power augmentation than cold water immersion. These observed changes were primarily in the high alpha band (10-12 Hz) and were larger in electrodes ipsilateral rather than contralateral to the stimulation. There was also an increase of beta bilaterally in frontal and posterior regions with cold water immersion. Our data demonstrate sustained topographic EEG responses during tonic stimulation from hand immersion in painfully cold water. These changes differ from those produced by stimulation with cool water immersion.

Adolescent↗

PubMed1996

The influence of immersion solutions on the viscoelasticity of temporary soft lining materials.

OBJECTIVES: The purpose of this study was to examine the influence of laboratory immersion in a number of solvents on the viscoelasticity of temporary soft lining materials. It was an initial attempt to reproduce the changes seen clinically with a view to formulating more clinically relevant immersion regimes for the evaluation of these materials. METHODS: Changes in the viscoelasticity of four temporary soft lining materials following immersion at 37 + or - 1 degree C in 10% acetone/90% water, 20A% acetone/80% water and hexane was compared to a control immersion in distilled water using a penetrometer modified to record creep strain and strain during recovery. Testing was performed at 2 h and 24 h and then at 2, 4, 7, 21 and 28 d after sample preparation. Summary measures were used to describe individual specimen changes in derived values of initial and time dependent compliance and elastic recovery from 0-7, 7-28 and 0-28 d. RESULTS: Immersion in hexane resulted in at least a 50% reduction in compliance of 28 d. There was a significantly greater reduction in compliance for hexane immersion than for any other solvent (p<0.01). Immersion in 20% acetone resulted in an increase in compliance of around 1 mm/N after 1 wk compared with a reduction of up to 1 mm/N in distilled water. There was a reduction in elastic recovery for 3 out of 4 materials with 20% acetone/80% water solution. Changes in elastic recovery were smaller than those of compliance. SIGNIFICANCE: The reduction in compliance with hexane immersion suggests that this, or similar solvents, may form the basis of more clinically relevant immersion regimes. This may contribute to the development of improved temporary soft lining materials.

Acetone↗

PubMed2003

Changes in heart rate variability in horses during immersion in warm springwater.

OBJECTIVE: To determine the effects of immersion in warm springwater (38 degrees to 40 degrees C) on autonomic nervous activity in horses. ANIMALS: 10 male Thoroughbreds. PROCEDURE: Electrocardiograms were recorded from horses for 15 minutes during a warm springwater bath after being recorded for 15 minutes during stall rest. Variations in heart rate (HR) were evaluated from the power spectrum in terms of low frequency (LF, 0.01 to 0.07 Hz) power and high frequency (HF, 0.07 to 0.6 Hz) power as indices of autonomic nervous activity. RESULTS: Mean (+/- SE) HR during stall rest and immersion in warm springwater was 31.1 +/- 1.7 and 30.3 +/- 1.0 beat/min, respectively. No significant difference was found between the HR recorded during stall rest and that recorded during immersion in warm springwater. The HF power significantly increased from 1,361 +/- 466 milliseconds2 during stall rest to 2,344 +/- 720 milliseconds2 during immersion in warm springwater. The LF power during stall rest and immersion in warm springwater was 3,847 +/- 663 and 5,120 +/- 1,094 milliseconds2, respectively, and were not significantly different from each other. Similarly, the LF:HF ratio did not change during immersion in warm springwater. The frequency of second-degree atrioventricular block, which was observed in 2 horses, increased during immersion in warm springwater, compared with during stall rest. CONCLUSIONS AND CLINICAL RELEVANCE: Increases in HF power indicates that the parasympathetic nervous activity in horses increases during immersion in warm springwater. Thus, immersion in warm springwater may provide a means of relaxation for horses.

Animals↗

PubMed1993

Renal and cardiovascular responses to water immersion in trained runners and swimmers.

The purpose of this study was to determine if fluid-electrolyte, renal, hormonal, and cardiovascular responses during and after multi-hour water immersion were associated with aerobic training. Additionally, we compared these responses in those who trained in a hypogravic versus a 1-g environment. Seventeen men comprised three similarly aged groups: six long-distance runners, five competitive swimmers, and six untrained control subjects. Each subject underwent 5 h of immersion in water [mean (SE)] 36.0 (0.5) degrees C to the neck. Immediately before and at each hour of immersion, blood and urine samples were collected and analyzed for sodium (Na), potassium, osmolality, and creatinine (Cr). Plasma antidiuretic hormone and aldosterone were also measured. Hematocrits were used to calculate relative changes in plasma volume (% delta Vpl). Heart rate response to submaximal cycle ergometer exercise (35% peak oxygen uptake) was measured before and after water immersion. Water immersion induced significant increases in urine flow, Na clearance (CNa), and a 3-5% decrease in Vpl. Urine flow during immersion was greater (P < 0.05) in runners [2.4 (0.4) ml.min-1] compared to controls [1.3 (0.1) ml.min-1]. However, % delta Vpl, CCr, CNa and CH2O during immersion were not different (P > 0.05) between runners, swimmers, and controls. After 5 h of immersion, there was an increase (P < 0.05) in submaximal exercise heart rate of 9 (3) and 10 (3) beats.min-1 in both runners and controls, respectively, but no change (P > 0.05) was observed in swimmers.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1996

The effect of water leakage on the results obtained from human and thermal manikin tests of immersion protective clothing.

The effect of both the volume and location of water leakage on the protection provided by an uninsulated immersion suit was investigated using human subjects and, in corresponding experiments, an immersion thermal manikin. Three volumes of "leakage" to the torso (200, 500 and 1000 ml) were examined, as were two conditions in which no leakage was simulated and one condition in which a 500-ml leak to the limbs was simulated. All leakages were introduced in a standardised way before immersion. The measurements of clothing insulation obtained, both from the manikin and the humans, were in general agreement. The human experimentation provided some support for a 200-ml limit to water leakage in tests of immersion suits. Rectal and aural temperatures remained significantly (P < 0.05) higher when a 500-ml leak was applied to the limbs rather than the torso; this was primarily due to greater heat flow through and from the torso (back) during the immersions with torso wetting. The physiological responses and anthropometric characteristics which determine this response are not present in manikins; the implications of this for the application and design of immersion thermal manikins, as well as the protection of those at risk of immersion in cold water, are discussed. It is concluded that using immersion thermal manikins to provide a single overall measure of clothing insulation will not necessarily distinguish between suits which provide quite different levels of protection for humans.

Body Temperature↗

PubMed1999

Ultrasound measurement on the calcaneus: influence of immersion time and rotation of the foot.

The aim of this study was to evaluate the influence of immersion time and rotation of the heel around the leg axis on the reproducibility of measurements using an ultrasound bone imaging scanner (UBIS) with a temperature-controlled water bath. Measurements were obtained in 10 men, 11 premenopausal women and 10 postmenopausal women. The right foot of all subjects was scanned 12 times with an interval of 3 min between each scan. The first 10 measurements, performed to study the effect of immersion time, were taken without intermediate repositioning. Measurements 11 and 12 were also taken without removing the foot, but the calcaneus position was varied by an angle of +/-2.5 degrees with respect to the reference position used during the first 10 measurements. Prolonged immersion of the heel led to a decrease in the variations of quantitative ultrasound (QUS) parameters between successive measurements. Following rapid variations with immersion time, the QUS parameters reached a plateau. The effect of immersion time on measurement error remained significant until the first two or three scans for broadband ultrasound attenuation (BUA) and until the sixth or seventh scans for speed of sound (SOS). The variation in BUA was more pronounced (p<0.05) for the group of postmenopausal women (20. 7% change in BUA between the first and tenth scans; p<0.005) than for the group of premenopausal women (6.8% change in BUA between the first and tenth scans; p<0.005). The variations in SOS were similar in the two groups (0.8% variation; p<0.005). The impact of immersion time was smaller for men than for women [2.5%, (p<0.01) and 0.4% (p<0.005) of the change between the first and tenth scans for BUA and SOS respectively]. On the whole, the measurement errors due to rotation of the heel were lower than those caused by immersion time. The variations were significant only in men and premenopausal women. Both immersion time and rotation of the heel may play a role in the precision of QUS and should be carefully standardized, particularly for longitudinal studies. In addition, following these results we have adopted a standardized protocol to derive the technique reproducibility in groups of premenopausal and postmenopausal women. The coefficients of variation were 1.1% for BUA and 0.1% for SOS in premenopausal women, and 1.4% for BUA and 0.13% for SOS in postmenopausal women.

Adult↗

PubMed2005

Effects of waterproof covering on hand immersion tests using water at 10 degrees C, 12 degrees C and 15 degrees C for diagnosis of hand-arm vibration syndrome.

OBJECTIVES: To compare effects of waterproof covering on finger skin temperature (FST) and subjective hand pain during immersion tests using cold water at 10 degrees C, 12 degrees C and 15 degrees C. In the (Draft International Standard) of the International Organization for Standardization (ISO/DIS 14835-1), a water temperature of 12 degrees C and use of water covering are proposed. METHODS: Six healthy male subjects took part in the immersion tests and immersed both hands into water at 10 degrees C, 12 degrees C and 15 degrees C for 5 min, repeatedly, with waterproof covering (polyethylene gloves) or without (bare hands). The FST data from middle fingers and subjective pain scores for hand pain were analyzed. Furthermore, the test with water at 12 degrees C was repeated to assess the repeatability of the test. RESULTS: The glove and water temperature factors for FST were significant at every minute from 1 min during immersion up to 2 min after recovery, showing higher values for waterproof covering than for bare hands and showing lowest values for water temperature of 10 degrees C and highest for 15 degrees C. The glove and water temperature factors for subjective pain score were significant at the 1-min and 2-min points during immersion, showing lower scores for waterproof covering than for bare hands and showing highest scores for water temperature of 10 degrees C and lowest for 15 degrees C. The results of the first and second tests using water of 12 degrees C showed no systematic difference in FST and hand pain between the tests, with a few exceptions. CONCLUSIONS: Subjective pain during the cold immersion test with polyethylene gloves and water at 12 degrees C can be reduced, while the differences in FST between water temperatures of 10 degrees C and 12 degrees C were small or not apparent at some points during immersion and recovery. The test also seems to be suitable for repeatability. Further investigation on hand-arm vibration syndrome (HAVS) patients to validate the use of the immersion test with gloves to obtain sufficient data for diagnostic value is required.

Adult↗

PubMed2003

Direct and indirect methods for determining plasma volume during thermoneutral and cold-water immersion.

Plasma volume (PV), determined indirectly from changes in haematocrit (Hct) and haemoglobin concentration ([Hb]), underestimates the absolute PV change (Evans blue dye) during thermoneutral immersion. Since PV changes during cold-water immersion have only been determined indirectly, we hypothesised that a similar underestimation may occur. Therefore, we compared the indirectly-measured PV with a direct-tracer dilution method (Evans blue dye column elution) in seven healthy males, during three, 60-min exposures: air (control; 21.2 degrees C), thermoneutral immersion (34.5 degrees C) and cold-water immersion (18.6 degrees C). During thermoneutral immersion, the directly-measured PV increased by 16.2 (1.4)% (P<0.05) and the indirectly-measured by 8.5 (0.8)% (P<0.05), with the latter underestimating the former by 43 (9.1)% (P<0.05). During cold immersion, the direct PV decreased by 17.9 (3.0)% (P<0.05) and the indirect by 8.0 (1.2)% (P<0.05), with the latter representing a 52 (6.8)% (P<0.05) underestimation of the direct PV change. Directionally-equivalent underestimations of PV change occur when using the indirect method during both thermoneutral and cold-water immersion. The assumptions inherent in the indirect method (constant F-cell ratio) appear to be violated during water immersion.

Adult↗

PubMed1997

The effect of blood alcohol on the initial responses to cold water immersion in humans.

Many drowning victims have alcohol in their blood, but it is not clear whether there is a causal relationship. This study examined the effect of moderate alcohol consumption on the initial responses to cold water immersion. Sixteen subjects wearing swimming costumes undertook two, 3-min head-out seated immersions in water at 15 degrees C. One hour before immersion, subjects drank either 3.7 ml.kg body water-1 of 40% v:v alcohol as vodka, or an equivalent volume of water (control) mixed with squash. On immersion, the average blood alcohol concentration was 23 mmol.l-1 (105 mg.100 ml-1) after alcohol consumption and zero in the control condition. Respiratory frequency in the first 20 s of immersion was found to be reduced (P < 0.05) by 10% (a total of 2-3 breaths) after alcohol consumption compared to the control immersion. Tidal volume, heart rate, rectal temperature and skin temperatures did not differ significantly between immersions. It is concluded that moderate alcohol consumption does not attenuate the initial "cold shock" responses to a practically significant extent and is thus unlikely to reduce the risk of drowning on immersion in cold water.

Adult↗

PubMed1988

Role of atrial natriuretic peptide in the natriuretic response to central volume expansion induced by head-out water immersion in sodium-retaining cirrhotic subjects.

PURPOSE: It is possible that abnormalities in atrial natriuretic peptide may be involved in the pathogenesis of sodium retention in edema states. We performed a study in a group of 12 sodium-retaining cirrhotic subjects to determine the role of this peptide in mediating differences in the natriuretic response to central volume expansion induced by head-out water immersion. PATIENTS AND METHODS: Each patient was maintained for seven days on a 20-mmol sodium intake, and then studied on both control and immersion days. On each day, measurements of the following were obtained: plasma atrial natriuretic peptide, hematocrit, electrolytes, creatinine, plasma renin activity, serum aldosterone, urinary cyclic guanosine monophosphate (cGMP), blood pressure, and pulse rate. RESULTS: In six subjects, immersion resulted in a marked natriuresis sufficient to induce negative sodium balance by the third hour, and these subjects were termed "responders." In these six patients, baseline pre-immersion levels of plasma renin activity and serum aldosterone were all below 3 ng/liter/second and 4 nmol/liter, respectively. In the other six subjects, the natriuretic response to immersion was markedly blunted and insufficient to induce negative sodium balance, and these subjects were termed "non-responders." In these subjects, baseline pre-immersion levels of plasma renin activity and aldosterone were all above 3.5 ng/liter/second and 5 nmol/liter, respectively, and were significantly elevated compared with the responders, and compared with the normal range for control subjects consuming the same sodium intake. In both groups of cirrhotic subjects, baseline levels of plasma atrial natriuretic peptide and cGMP excretion were significantly and comparably elevated compared with the normal range for control subjects ingesting the same sodium intake. Despite the marked difference in the natriuretic response to immersion in both responders and non-responders, there was a significant and comparable further elevation of plasma atrial natriuretic peptide and urinary cGMP excretion during immersion, compared with the control day. CONCLUSION: These results suggest that the relative resistance to the natriuretic action of atrial natriuretic peptide in the non-responders compared with the responders is mediated by anti-natriuretic factors acting at a level parallel with or beyond atrial natriuretic peptide release or coupling to its cGMP-linked receptors.

Adult↗

PubMed2006

Water immersion in preeclampsia.

OBJECTIVE: Preeclampsia is associated with profound vasoconstriction in most organ systems and reduced plasma volume. Because water immersion produces a marked central redistribution of blood volume and suppresses the renin-angiotensin system response and sympathetic activity, we hypothesized that water immersion might be useful in the treatment of preeclampsia. STUDY DESIGN: The effects of thermoneutral water immersion for 3 hours on central and peripheral hemodynamics were evaluated in 7 preeclamptic patients, 7 normal pregnant control patients, and 7 nonpregnant women. Finger plethysmography was used to determine hemodynamic measurements (cardiac output and total peripheral resistance), and forearm blood flow was measured by strain gauge plethysmography. Postischemic hyperemia was used to determine endothelium-dependent vasodilation. Analysis was by analysis of variance for repeated measurements. RESULTS: During water immersion cardiac output increased while diastolic blood pressure and heart rate decreased, although systolic blood pressure remained unchanged in each group. Forearm blood flow increased significantly in the normal pregnant and preeclamptic subjects. Total peripheral resistance decreased in all groups, but values in preeclamptic patients remained above those of normotensive pregnant women. Water immersion had no effect on endothelium-dependent vasodilation in the preeclamptic group, and most hemodynamic changes that were observed reversed to baseline within 2 hours of completion of the procedure. CONCLUSION: Although water immersion results in hemodynamic alterations in a manner that is theoretically therapeutic for women with preeclampsia, the effect was limited and short-lived. In addition water immersion had no effect on endothelium-dependent vasodilation in women with preeclampsia. The therapeutic potential for water immersion in preeclampsia appears to be limited.

Adult↗

PubMed2003

Increased efficacy of immersion vaccination in fish with hyperosmotic pretreatment.

Immersion vaccination is common practice in aquaculture, because of its convenience for mass vaccination with sufficient protection. However, the mechanisms of antigen uptake and presentation, resulting in a protective immune response and the role of the innate immune system therein are largely unknown. The impact of immersion vaccination on fish physiology and on the ensuing innate and specific immune response was characterized with fluorescently labeled particulate and soluble model antigens. Vaccination of common carp by direct immersion (DI) or hyperosmotic immersion (HI; direct immersion, preceded by a brief immersion in a hypertonic solution) greatly enhanced the uptake of soluble, but not particulate antigen through temporary disruption of the integrity of the epithelia of gills and skin. Damage induced is mild and does not impose additional stress over the handling associated with immersion vaccination. Especially HI briefly but strongly activates the innate immune system. We conclude that HI more effectively increased the uptake of vaccine and enhanced the efficacy by which vaccine components are processed and presented by the innate immune system, dually enhancing the mucosal immune response. Understanding the mechanisms involved in uptake and processing of vaccine in the early phase of the immune response will greatly benefit the design of immersion vaccination.

Aeromonas↗

PubMed1986

Impaired sodium excretion in response to volume expansion induced by water immersion in insulin-dependent diabetes mellitus.

The renal response to volume expansion produced by water immersion to the neck at 35 degrees C was examined in eight young normotensive uncomplicated insulin-dependent diabetic subjects and in eight matched normal control subjects. Both the diabetic and normal subjects manifested a renal response of natriuresis and kaliuresis on immersion, but the natriuretic response was reduced in the diabetic group. Thus the induced excretion of sodium over the 4 h of immersion was 40 +/- 5 mmol (mean +/- SEM) in the normal group compared with 22 +/- 4 mmol in the diabetic group (P less than 0.02). In the normal subjects creatinine clearance did not change during immersion compared with pre-immersion control values while in the diabetic group it rose from pre-immersion control values of 112 +/- 11 ml/min to a mean value of 127 +/- 11 ml/min during immersion (P less than 0.01). The diabetic subjects thus excreted less sodium despite an increased filtered load during water immersion. Fractional excretion of sodium was significantly reduced in the diabetic subjects compared with the normal control subjects (P less than 0.05). The suppression of plasma renin and aldosterone was similar in normal and diabetic groups. Tubular sodium retention could be an early functional change in the diabetic kidney, and be implicated in the development of diabetic nephropathy.

Aldosterone↗

PubMed2000

Water immersion stress induces heat shock protein 60 expression and protects against pancreatitis in rats.

BACKGROUND & AIMS: Heat shock proteins (Hsps), induced by cell stress, are known to protect against cellular injury. Recent studies have indicated that Hsp60 expression, induced by exposure to water immersion stress, protects against pancreatitis induced by administration of supramaximal doses of cerulein in rats. However, the mechanisms responsible for this protection are not known. METHODS: Rats were water-immersed for 3-12 hours. Pancreatitis was induced by cerulein administration. RESULTS: The results confirm that prior induction of Hsp60 expression by water-immersion stress significantly ameliorates the severity of cerulein-induced pancreatitis as judged by the markedly reduced degree of hyperamylasemia, pancreatic edema, and acinar cell necrosis. Water immersion also prevents the subcellular redistribution of cathepsin B from a lysosome-enriched fraction to a heavier, zymogen granule-enriched fraction that is known to occur in this model of pancreatitis. Intra-acinar cell activation of trypsinogen that occurs shortly after exposure to a supramaximally stimulating dose of cerulein both in vivo and in vitro is prevented by prior water-immersion stress and Hsp60 expression. The protection against pancreatitis that follows water-immersion stress is not caused by alterations of cholecystokinin receptors, because water immersion does not alter the typical biphasic amylase secretory response to stimulation with cerulein. CONCLUSIONS: Water-immersion stress induces Hsp60 expression, ameliorates cerulein-induced pancreatitis, and prevents intra-acinar cell activation of trypsinogen. We suggest that Hsp60 protects against cerulein-induced pancreatitis by preventing trypsinogen activation within acinar cells.

Amylases↗

PubMed1969

Cardiovascular responses to partial and total immersion in man.

1. Short-term cardiovascular effects of partial and total immersion of eighteen human subjects in the horizontal plane have been examined. Brachial arterial pressure, heart rate, forearm blood flow and respiratory movements were monitored simultaneously throughout the experiments. Forearm vascular resistance was calculated from the mean blood pressure and mean flow.2. Total immersion, including the face, with breath-holding resulted in a 61 +/- 43% increase in forearm vascular resistance with an associated 29 +/- 15% reduction in forearm blood flow. The concurrent bradycardia was significantly different from the heart rate changes during breath-holding with the torso only immersed, or during total immersion with snorkel-breathing. Neither breath-holding in air or with only the torso immersed, nor total immersion with snorkel-breathing produced such a diving response.3. Breath-holding, after several minutes of total immersion and snorkel-breathing, produced an attenuated diving response. It therefore appears that a full diving response can be obtained only when the apnoea commences at the moment of face immersion.4. The present investigation supports the concept that in man face immersion is an essential predisposing factor for the diving response, and cortical inhibition of the respiratory centre is important for its initiation and maintenance.

Adolescent↗