PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Salinity”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5Linked to original sources
PubMed2007

Osmotherapy with hypertonic saline attenuates water content in brain and extracerebral organs.

OBJECTIVE: Because of their beneficial effects in patients with hemorrhagic shock and multiple-system trauma, hypertonic saline solutions are increasingly being used perioperatively for volume resuscitation. Although the anti-edema effects of hypertonic saline on brain are well documented in a variety of brain injury paradigms, its effects on the water content on other organs has not been studied rigorously. In this study, we tested the hypothesis that a) hypertonic saline when given as an intravenous bolus and continuous infusion attenuates water content of small bowel, lung, and brain in rats without neuro-injury; and b) attenuation of stroke-associated increases in lung water is dependent on achieving a target serum osmolality. DESIGN: Prospective laboratory animal study. SETTING: Research laboratory in a teaching hospital. SUBJECTS: Adult male Wistar rats. INTERVENTIONS: In the first series of experiments, under controlled conditions of normoxia, normocarbia, and normothermia, spontaneously breathing, halothane-anesthetized (1.0-1.5%) adult male Wistar rats (280-320 g) were treated in a blinded randomized fashion with 7.5% hypertonic saline or 0.9% normal saline in a 8-mL/kg intravenous infusion for 3 hrs followed by a continuous intravenous infusion (1 mL/kg/hr) of 5% hypertonic saline or normal saline, respectively (n=10 each), for 48 hrs. A second group of rats were treated with continuous infusion only for 48 hrs of either 7.5% hypertonic saline or normal saline (1 mL/kg/hr) (n=10 each) without an intravenous bolus. Naïve rats served as controls (n=10). Tissue water content of small bowel, lung, and brain was determined by comparing the wet-to-dry ratios at the end of the experiment. In a second series of experiments, rats (n=94) were subjected to 2 hrs of transient middle cerebral artery occlusion by the intraluminal occlusion technique. At 6 hrs following middle cerebral artery occlusion, rats were treated in a blinded randomized fashion with a continuous intravenous infusion of normal saline, 3% hypertonic saline, or 7.5% hypertonic saline for 24, 48, 72, and 96 hrs. Surgical shams served as controls (n=7). Hypertonic saline was instituted as chloride/acetate mixture (50:50) in all experiments. Serum osmolality was determined at the end of the experiment in all animals. MEASUREMENTS AND MAIN RESULTS: In rats without neuro-injury that received intravenous bolus followed by a continuous infusion, lung water content was significantly reduced with hypertonic saline (73.9+/-1.1%; 359+/-10 mOsm/L) (mean+/-sd) compared with normal saline treatment (76.1+/-0.53%; 298+/-4 mOsm/L) as was water content of small bowel (hypertonic saline, 69.1+/-5.8%; normal saline, 74.7+/-0.71%) and brain (hypertonic saline, 78.1+/-0.87%; normal saline, 79.2+/-0.38%) at 48 hrs. Stroke-associated increases in lung water content were attenuated with 7.5% hypertonic saline at all time points. There was a strong correlation between serum osmolality and attenuation of stroke-associated increases in lung water content (r=-.647) CONCLUSIONS: Bowel, lung, and brain water content is attenuated with hypertonic saline when serum osmolality is >350 mOsm/L without adverse effect on mortality in animals with and without neuro-injury. Attenuation of water content of extracerebral organs with hypertonic saline treatment may have therapeutic implications in perioperative fluid management in patients with and without brain injury.

Animals↗
PubMed1997

In vivo model of muscle pain: quantification of intramuscular chemical, electrical, and pressure changes associated with saline-induced muscle pain in humans.

Intramuscular injection of hypertonic saline is a good model to study human muscle pain (Kellgren 1938). The present study concerns the intramuscular (i.m.) pain mediators in saline-induced muscle pain. In experiment 1, the diffusion of infused hypertonic and isotonic saline (0.5 ml) in m. tibialis anterior was illustrated by magnetic resonance imaging (MRI) in one subject. In experiment 2, six volunteers received four sequential infusions (0.5 ml given at 5 min intervals) of isotonic saline and thereafter four sequential infusions (0.5 ml given at 5 min intervals) of hypertonic saline into m. tibialis anterior. The isotonic and hypertonic saline infusions were computer-controlled and separated by 20 min. The muscle pain intensity was assessed by continuous recordings on a visual analogue scale (VAS). One microdialysis probe was inserted 1 cm from the infusion needle in m. tibialis anterior and another probe in the other m. tibialis anterior. Concentrations of the i.m. sodium, potassium, magnesium, and prostaglandin E2 (PGE2) were assessed from the dialysates. Intramuscular electromyography (EMG) and pressure were assessed in the area of the infused saline. In experiment 1, the infusion of hypertonic and isotonic saline created a visible saline-pool on the MRI scans. These saline-pool volumes were stable and not correlated to the pain scores. In experiment 2, infusion of isotonic saline produced little pain compared to infusion of hypertonic saline. Maximal pain was reported after the first infusion of hypertonic saline and thereafter the pain gradually decreased with subsequent infusions of hypertonic saline. During infusion of hypertonic saline the i.m. sodium and potassium concentrations increased significantly, i.m. magnesium concentration tended to be increased, and the i.m. PGE2 concentration tended to be decreased although these changes were not significant. The i.m. EMG was smaller during and after infusions of hypertonic saline compared with isotonic saline. The i.m. pressure was not different during the infusions of hypertonic and isotonic saline but was increased between the infusions of hypertonic saline. This study has shown that i.m. infusion of hypertonic saline produced a saline-pool, causing the i.m. pressure to increase. Possibly, pain activation and cessation are related to increased intramuscular sodium and potassium content respectively.

Adult↗
PubMed2006

Hypertonic saline enhances host defense to bacterial challenge by augmenting Toll-like receptors.

OBJECTIVE: To determine whether hypertonic saline infusion modulates thermal injury-induced bacterial translocation and host response to bacterial challenge through the augmentation of Toll-like receptors (TLRs). DESIGN: Prospective, experimental study. SETTING: Research laboratory at a university hospital. SUBJECTS: Thermal injury models in the mice. INTERVENTIONS: In experiment 1, mice underwent burn were given with 10 mL/kg hypertonic saline (7.5% NaCl), 10 mg/kg saline (N/S1), or 80 mL/kg saline (N/S2) at 4 or 8 hrs after burn. At 24 hrs after burn, mesenteric lymph nodes were harvested for bacterial translocation assay. In experiment 2, mice receiving hypertonic saline or saline after thermal injury received peritoneal challenge with Escherichia coli, and bacterial clearance was measured. In experiment 3, peritoneal cells from mice receiving hypertonic saline or saline after thermal injury were incubated with E. coli, and bacterial count, TLR2, TLR4, MIP2, CXCR2, pp38, and ERK expression were evaluated. In experiment 4, reactive oxygen species production, CXCR2, MIP2, TLR2, and TLR4 expression of bone marrow neutrophil from mice receiving hypertonic saline or saline treatment after thermal injury were evaluated. In experiment 5, neutrophil were cultured with hypertonic saline or N/S and incubated with E. coli. TLR2 and TLR4 expression and bacterial count were evaluated. In experiment 6, mice were fed with oral antibiotics with or without lipopolysaccharide, a TLR ligand, supplements. At 24 hrs after burn, mesenteric lymph nodes were harvested for bacterial translocation assay, and neutrophils were harvested for TLR2 and TLR4 protein assay. MEASUREMENTS AND MAIN RESULTS: Hypertonic saline decreased thermal injury-induced bacterial translocation. Hypertonic saline increased bacterial clearance, phagocytic activity, and TLR2, TLR4, CXCR2, pp38, and p44/42 expression of peritoneal cells. Hypertonic saline treatment at 4 or 8 hrs after thermal injury decreased reactive oxygen species production of neutrophil. Hypertonic saline injection increased TLR2, TLR4, and pp38 expression of neutrophil. In vitro treatment of neutrophil with hypertonic saline increased phagocytic activity and TLR2 and TLR4 expression. Commensal depletion with oral antibiotics decreased TLR2 and TLR4 expression of neutrophil; lipopolysaccharide increased TLR4 expression of neutrophil and decreased thermal injury-induced bacterial translocation. CONCLUSIONS: Restoration of extracellular fluid in burn shock with hypertonic saline decreased thermal injury-induced bacterial translocation. Hypertonic saline increased the phagocytic activity and TLR2, TLR4, CXCR2, pp38, and P44/42 expression of peritoneal cells. Hypertonic saline decreased reactive oxygen species but increased TLR2, TLR4, and pp38 expression and phagocytic activity of bone marrow neutrophil. Stimulation of the TLRs with lipopolysaccharide in commensal depleted mice increased TLRs expression of neutrophil and decreased thermal injury-induced bacterial translocation. Taken together with the fact that stimulation of TLRs with hypertonic saline increases phagocytic activity of systemic inflammatory cells, we conclude that TLRs play a critical role in the innate immunity by recognizing bacteria and that hypertonic saline enhances host response to bacterial challenge by increasing TLRs of inflammatory cells.

Animals↗
PubMed1988

Salinity Effects on Photosynthesis, Carbon Allocation, and Nitrogen Assimilation in the Red Alga, Gelidium coulteri.

The long-term effects of altered salinities on the physiology of the intertidal red alga Gelidium coulteri Harv. were assessed. Plants were transfered from 30 grams per liter salinity to media with salinities from 0 to 50 grams per liter. Growth rate, agar, photosynthesis, respiration, and various metabolites were quantified after 5 days and 5 weeks adaptation. After 5 days, growth rates were lower for plants at all altered salinities. Growth rates recovered from these values with 5 weeks adaptation, except for salinities of 10 grams per liter and below, where tissues bleached and died. Photosynthetic O(2) evolution was lower than control values at both higher and lower salinities after 5 days and did not change over time. Carbon fixation at the altered salinities was unchanged after 5 days, but decreased below 25 grams per liter and above 40 grams per liter after 5 weeks. Respiration increased at lower salinities. Phycobili-protein and chlorophyll were lower for all altered salinities after 5 days. These decreases continued at lower salinities, then were stable after 5 weeks. Chlorophyll recovered over time at higher salinities. Decreases in protein at lower salinities were quantitatively attributable to phycobili-protein loss. Total N levels and C:N ratios were nearly constant across all salinities tested. Carbon flow into glutamate and aspartate decreased with both decreasing and increasing salinities. Glycine, serine, and glycolate levels increased with both increasing and decreasing salinity, indicating a stimulation of photorespiration. The cell wall component agar increased with decreasing salinity, although biosynthesis was inhibited at both higher and lower salinities. The storage compound floridoside increased with increasing salinity. The evidence suggests stress responses to altered salinities that directly affected photosynthesis, respiration, and nitrogen assimilation and indirectly affected photosynthate flow. At low salinities, respiration and photorespiration exceeded photosynthesis with lethal results. At higher salinities, although photosynthesis was inhibited, respiration was low and carbon fixation adequate to offset increased photorespiration.

Journal Article↗
PubMed2003

Saline, mannitol, and furosemide hydration in acute cisplatin nephrotoxicity: a randomized trial.

OBJECTIVE: To determine which hydration (saline, saline + mannitol, or saline + furosemide) is associated with least cisplatin nephrotoxicity. METHODS: We randomized 49 women who received cisplatin (75 mg/m(2) every 3 weeks) into one of the three hydration arms. The 24-h creatinine clearance was measured before and on day 6 after cisplatin infusion. The patients of each arm received 2 l of saline hydration. In the saline + furosemide arm, 40 mg of furosemide was given after hydration. In the saline + mannitol arm, 50 g of mannitol was mixed with the cisplatin. RESULTS: For the first cycle of chemotherapy, 15 women were randomized to saline, 17 to saline + furosemide, and 17 to saline + mannitol. For each group, the creatinine clearances before cisplatin infusion were (means+/-SD, milliliters per minute) 84.5+/-26.8, 82.5+/-24.0 and 87.4+/-25.6, and after cisplatin infusion were 79.1+/-31.9, 68.7+/-21.5, and 56.4+/-22.9, respectively. The decreases in creatinine clearance were similar between the saline group and the saline + furosemide group ( P=0.66), but different between the saline + mannitol group and the saline group ( P=0.02) or the saline + furosemide group ( P=0.02). As each woman received multiple courses of cisplatin, 15 who received saline contributed 41 paired datasets, 17 who received saline + furosemide contributed 49 paired datasets, and 17 who received saline + mannitol contributed 36 paired datasets showed similar patterns. CONCLUSIONS: Hydration with saline or saline + furosemide appears to be associated with less cisplatin nephrotoxicity than saline + mannitol.

Adult↗
PubMed1998

Interactive effects of salinity on metabolic rate, activity, growth and osmoregulation in the euryhaline milkfish (Chanos chanos)

The euryhaline milkfish (Chanos chanos) is an excellent subject for studies of the physiological and behavioral processes involved in salinity adaptation. In this study, energy partitioning for metabolism, activity and growth, maximal activity performance and blood osmotic concentrations were assessed at two activity levels in juvenile milkfish fed equal rations and maintained at a relatively constant temperature (262 C) and at salinities (15, 35 and 55 ?) that represented a wide range of osmoregulatory challenges. Changes in the measured parameters were not consistently related to the magnitude of the trans-integumentary osmotic gradients. Routine oxygen consumption rates were high in 35 ? salinity (mean 1 s.e.m. 1678 mg O2 kg-1 h-1) and comparably low in 15 and 55 ? salinity (1336 and 1273 mg O2 kg-1 h-1, respectively). Routine activity levels (relative swimming velocity) were highest in 35 ? salinity (0. 960.04 L s-1), where L is standard length, intermediate in 15 ? salinity (0.770.03 L s-1) and lowest in 55 ? salinity (0.670.03 L s-1). Growth was significantly higher in 55 ? salinity (3.40.2 % increase in wet body mass per day) than in 35 ? salinity (2.40.2 % increase per day) and intermediate in 15 ? salinity (2.90.5 % increase per day). Maximum swimming velocities decreased with increases in salinity, from 9.90.7 L s-1 in 15 ? salinity to 6.60. 5 L s-1 in 55 ? salinity. Sustained swimming activity above routine levels for 2 h resulted in an increase in blood osmotic concentrations in milkfish in 55 ? salinity, but osmoregulation was re-established during the second 2 h of activity. Thus, patterns of variation in metabolic rate and growth were largely parallel to variations in routine activity although, comparing 15 and 55 ? salinity, elevated maintenance costs for osmoregulation at the high salinity were detectable. Reduced osmoregulatory abilities and reductions in maximal swimming performance suggest that high salinity may constrain activity. The results demonstrate that investigations of salinity adaptation in euryhaline fishes should take into account the interactive effects of salinity on physiology and behavior.

Journal Article↗
PubMed2006

Hemodynamic effects of combined treatment with oxygen and hypertonic saline in hemorrhagic shock.

OBJECTIVE: In hemorrhagic shock, small volume resuscitation with hypertonic saline transiently increases mean arterial blood pressure (MABP) and cardiac output and augments organ perfusion. Inhalation of 100% oxygen after hemorrhage also increases MABP and redistributes blood flow to the splanchnic and renal vascular beds. We evaluated hemodynamic effects of combined resuscitation with hypertonic saline and oxygen in shock induced by controlled bleeding in rats. DESIGN: Animal study. SETTING: Research laboratory. SUBJECTS: Male Sprague-Dawley rats. INTERVENTIONS: Animals were assigned to four hemorrhage groups that received posttreatment with a) normal saline; b) normal saline + 100% oxygen; c) hypertonic saline; d) hypertonic saline + oxygen, and a fifth sham-shock group that received hypertonic saline + oxygen. MEASUREMENTS AND MAIN RESULTS: Bolus infusion of small volume hypertonic saline markedly increased MABP (p < .001), hindquarter vascular resistance (p < .05), and distal aorta blood flow (p < .01). Hypertonic saline transiently increased superior (cranial) mesenteric artery (SMA) blood flow (p < .001) and small bowel perfusion (p < .01). Inhalation of oxygen after normal saline rapidly increased MABP (p < .01) and hindquarter vascular resistance (p < .02) and decreased distal aorta blood flow (p < .02) and perfusion of the gracilis muscle (p < .05). When given after normal saline, oxygen did not change SMA resistance and increased SMA flow (p < .05). The supplementation of oxygen after hypertonic saline did not exert additional effects on vascular resistance and blood flows in the two vascular beds. However, the combined treatment prevented the oxygen-induced decrease in distal aorta blood flow and gracilis muscle perfusion and maintained MABP at slightly higher values and SMA flow at significantly higher values than hypertonic saline alone until the end of the protocol (p < .01). The two hemorrhaged groups treated with oxygen exhibited the lowest final plasma lactate concentrations (p < .05 from normal saline and hypertonic saline groups). CONCLUSIONS: We suggest that early combined use of hypertonic saline and oxygen exerts a favorable extended profile of hemodynamic effects that amends shortcomings of each treatment alone in hemorrhagic shock.

Analysis of Variance↗
PubMed2003

Inter-population differences in Cd, Cr, Se, and Zn accumulation by the green mussel Perna viridis acclimated at different salinities.

Trace metal (Cd, Cr, Se, and Zn) uptake from the dissolved phase, assimilation efficiency from the dietary phase, and metal body burden, as well as the clearance rate, apparent water permeability and gill surface area were measured in the green mussel Perna viridis collected from two contrasting salinity sites in Hong Kong coastal waters with following acclimation in the laboratory at different salinities. The concentrations of metals were 1.2-6.4x greater in mussels collected from the low salinity site, i.e. Tai O, as compared with Tap Mun (high salinity) mussels. Influx of Cd and Zn from the dissolved phase increased with decreased salinity. Furthermore, Cr(VI) and Se (selenite) influx were also affected by decreased salinity, in particular below 17 psu, suggesting that speciation was not the only factor to effect metal uptake. Long-term acclimation to different salinity also had an effect on metal uptake. Mussels collected from Tap Mun (high salinity) accumulated metals 1.2-2.2x faster than mussels from Tai O (low salinity) at intermediate and high experimental salinities >17 psu. Metal assimilation efficiencies were unaffected by salinity variation, but gut passage times were significantly longer at low (10 psu) salinities, indicating some effect of lowered salinity on mussels gut physiology. Gill surface area, which was similar in both populations of mussels, and filtration rate, which was generally similar or higher in those groups with low metal uptake, could not explain the inter-population difference in metal accumulation. Although there was no significant difference, due to high inter-individual variability, the apparent water permeability of the Tap Mun population was on average about 1.6x greater compared with Tai O mussels, and may partially account for the difference in metal uptake between these two populations acclimated at salinity >17 psu. Thus, the effect of salinity on metal uptake is dependent on metal biogeochemistry as well as a range of physiological responses. There was a clear effect of acclimation to lowered salinity on metal uptake, which may have important implications for metal accumulation modelling, biomonitoring, and toxicity studies.

Animals↗
PubMed2000

Combined effects of pentachlorophenol and salinity stress on phagocytic and chemotactic function in two species of abalone.

The effect of pentachlorophenol (PCP) combined with salinity stress on specific aspects of cellular immunity was examined in two species of abalone. Chemotactic and phagocytic ability (percent phagocytosis, %P; and phagocytic index, PI), as well as gross morphological characteristics, of hemocytes withdrawn from red (Haliotis rufescens) and black abalone (H. cracherodii) after in vivo exposure to 25, 35, or 45 per thousand seawater salinity plus 1.2 mg/l PCP were determined. Abalone exposures of 3.5 and 6.5 h, respectively, were based on species-specific metabolic endpoints (MEPs) derived from previous NMR data. Hemocyte chemotaxis was found to be augmented by low salinity in red but not black abalone, while high salinity seemed to reduce chemotactic ability in both species. PCP did not potentiate the effects demonstrated by salinity variations alone in red abalone, although chemotaxis was further compromised in black abalone exposed to high salinity stress combined with PCP. Although chemotactic ability was similar among both species, both %P and PI was greater among black abalone. Low salinity may offset the effects of PCP in red but not black abalone. Whereas red abalone demonstrated a reduction in phagocytic ability upon exposure to high salinity alone, black abalone appeared more resilient to high salinity stress alone. Furthermore, while the effect of high salinity plus PCP is subadditive among red abalone, high salinity seems to potentiate the effect of PCP on black abalone. Finally, hemocytes exposed to acute salinity variations plus PCP showed varying morphological characteristics when compared to controls. Over 30% of hemocytes of high salinity plus PCP exposed abalone remained rounded and generally unattached to glass slides with only a few pseudopod extensions. Hemocyte preparations incubated in rhodamine-conjugated phalloidin were observed with fluorescence microscopy and reveal an altered actin filament pattern. Overall, black abalone demonstrate greater phagocytic ability than red abalone both in the presence and absence of PCP. Furthermore, increases in salinity are accompanied with reduced phagocytic ability with red abalone demonstrating particular sensitivity to salinity variations. While PCP inhibits ATP synthesis, salinity variations may impose an additional stress on intertidal animals exposed to transient or seasonal environmental changes.

Journal Article↗
PubMed2002

Complexities in ETS-domain transcription factor function and regulation: lessons from the TCF (ternary complex factor) subfamily. The Colworth Medal Lecture.

The ETS-domain transcription factor family can be divided into a series of subfamilies. Elk-1 represents the founding member of the ternary complex factor (TCF) subfamily. By focusing on the TCF subfamily, we can demonstrate the complexities that exist in the function and regulation of ETS-domain transcription factors. This article focuses on Elk-1 in detail and summarizes the functions of other TCFs. The key themes covered include the domain structure of the TCFs, the mechanisms of complex formation with serum response factor, regulation of TCFs by mitogen-activated protein kinase cascades, and transcriptional regulatory properties of the TCFs. Finally, the emerging role of the TCFs in vivo is discussed. A picture is developing indicating that, while these proteins exhibit significant sequence and functional conservation, key differences in their structure and regulation are being identified which may relate to unique functions of these proteins in vivo.

Amino Acid Sequence↗