Effects of Na^+/K^+ Ratio of Groundwaters on the Gill Ion-Transport Enzyme Activity,Plasma Osmolality and Growth of Cynoglossus semilaevis Juveniles

The effects of environmental Na+/K+ ratio on the gill ion-transport enzyme activity,plasma osmolality and growth of Cynoglossus semilaevis juveniles were investigated. The results showed that,plasma osmolality was similar among flounder adapted to different Na+/K+ ratios of saline groundwaters (P>0.05),while the growth,gill Na+,K+-ATPase and HCO3--ATPase activities were affected by Na+/K+ ratio significantly (P<0.05). The gill Na+,K+-ATPase activity reached its maximum on day 3,then decreased gradually from day 3 to day 9 and remained constant from day 9 to day 15. The peak values of gill Na+,K+-ATPase activity were detected on day 3 for all Na+/K+ ratios of saline groundwaters,then the enzyme activities descended,and on day 9 the enzyme activi-ties achieved steady state,and the gill HCO3--ATPase activity increased rapidly and achieved steady state after one day. During steady state,the gill Na+,K+-ATPase and HCO3--ATPase activity of Na+/K+ ratios 20 and 40 treatments were significantly higher than those in the control group (Na+/K+ ratio 27.5),while there were no significant differences between the Na+/K+ ratio 30 treatment and the control group; the gill Na+,K+-ATPase activity of Na+/K+ ratio 20 and 40 treatments were significantly higher than that for ratio 30 treatment,but there were no significant differences of gill HCO3--ATPase activity among these treatments. At the end of the 15-day experiment,the weight gain (%) and specific growth rate (SGR) of flounders maintained in seawater were significantly higher than those in groundwaters; significant differences also occurred among the treatments; Na+/K+ ratio 30 treatment had the highest values (33.7% and 1.94 respectively),which were significantly higher than those under Na+/K+ ratios 20 and 40 treatments. There-fore,for the saline groundwater used in this experiment,it is suggested that the Na+/K+ ratio be adjusted to approximately 30,i.e.,as close to that of natural seawater as possible in the culture of flounder.

Oxygen permeability of soft contact lenses in different pH, osmolality and buffering solution

AIMTo determine the effect of pH, osmolality, and buffering system on the oxygen permeability (Dk) of soft contact lenses.METHODSTwo hydrogel lenses (nelfilcon A and etafilcon A) and 2 silicone hydrogel lenses (lotrafilcon A and balafilcon A) were used in the study. These lenses were incubated in phosphate-buffered saline (PBS) and borate-buffered saline (BBS) solutions adjusted by 0.8 pH increments to a pH in the range of 5.8-9.0 or in hypotonic (280 mOsmol/kg), isotonic (310 mOsmol/kg) and hypertonic (380 mOsmol/kg) PBS solutions. Polarographic method was used for measuring the Dk and lenses were stacked as 4 layers to correct the boundary effect.RESULTSDk values of all contact lenses measured in BBS solutions were more stable than those in PBS solutions. Especially the etafilcon A lens showed a relative big change compared with other types of contact lenses at the same conditions. When the osmolality of PBS solution increased from hypotonic to hypertonic, Dk of all contact lenses decreased. Variations in Dk existed depending on lens materials, etafilcon A lens was the most affected and nelfilcon A was the least affected by osmolality.CONCLUSIONFrom the result obtained, it is revealed that Dk of contact lenses is changed by the pH, osmolality, and buffering condition of tear. Thus, Dk of contact lens can be varied by the lens wearers' physiological and/or pathological conditions.

Serum osmolality and ions,and gill Na^(+)/K^(+)-ATPase of spottedtail goby Synechogobius ommaturus(R.)in response to acute salinity changes

This study was carried out to determine the effects of abrupt salinity change on osmoregulatory ability of the spottedtail goby Synechogobius ommaturus.720 juvenile fish(65.3±11.8 g)were transferred to 200 L tanks(with 40 juveniles in each tank),in which salinities were abruptly changed from 10 to 20,30,40,50 and freshwater.Survival rate,serum osmolality,electrolytes(Na^(+),Cl^(-),and K^(+))and gill Na^(+)/K^(+)-ATPase(NKA)activity were assessed successively in 528 h.Results showed serum osmolality,ion concentrations and gill Na^(+)/K^(+)-ATPase activity increased significantly when fish were transferred to salinity 40 and 50 and all fish in these groups died by the end of the experiment.Serum osmolality,Na^(+),Cl^(-)and K^(+)in fish transferred to a salinity of 20,30 and freshwater were not affected and no mortality was detected.Compared with the control group,a significantly decrease of NKA activity happened in the freshwater group,but the activity in 20 and 30 groups was not affected significantly.The results indicated that S.ommaturus could adapt rapidly and maintain homeostasis in a wide range of salinities(from freshwater to salinity 30)and this species may be suitable for aquaculture in estuarine and coastal areas where rapid salinity fluctuations commonly occur.

Clinical characteristics of non-alcoholic fatty liver disease in Chinese adult hypopituitary patients

BACKGROUND Patients with hypothalamic-pituitary disease have the feature of central obesity,insulin resistance, and dyslipidemia, and there is increased prevalence of liver dysfunction consistent with non-alcoholic fatty liver disease(NAFLD) in this population. The causes of hypopituitarism in the reported studies varied and combined pituitary hormone deficiency including central diabetes insipidus is much common in this population. This retrospective cross-sectional study was performed to analyze the clinical characteristics and related factors with NAFLD and cirrhosis in Chinese adult hypopituitary/panhypopituitary patients.AIM To analyze the clinical characteristics of and related risk factors for NAFLD in Chinese adult hypopituitary patients.METHODS Adult Chinese patients with hypopituitarism and/or panhypopituitarism were enrolled at the Pituitary Center of Peking Union Medical College Hospitalbetween August 2012 and April 2018. According to abdominal ultrasonography,these patients were divided into an NAFLD(-) group and an NAFLD(+) group,and the latter was further divided into an NAFLD group and a cirrhotic group.The data, such as patient characteristics, diagnosis, and treatment, were extracted from medical records, and statistical analysis was performed.RESULTS A total of 36 male and 14 female adult Chinese patients with hypopituitarism were included in this retrospective study; 43(87.0%) of these patients exhibited growth hormone(GH) deficiency, and 39(78.3%) had diabetes insipidus. A total of 27(54.0%) patients were diagnosed with NAFLD, while seven patients were cirrhotic. No significant differences were noted in serum GH or insulin-like growth factor 1 among patients with cirrhosis, subjects with NAFLD, and those without NAFLD. However, plasma osmolality and serum sodium concentration of the cirrhotic patients were 314.9 mOsm/kgH2 O and 151.0 mmol/L,respectively, which were significantly higher than those of the NAFLD patients(P = 0.036 and 0.042, respectively). Overweight/obesity and insulin resistance were common metabolic disorders in this population. The body mass index(BMI)and homeostasis model assessment of insulin resistance parameters of the cirrhotic patients were 27.7 kg/m2 and 9.57, respectively, which were significantly higher than those of the patients without NAFLD(P = 0.011 and0.044, respectively). A correlation analysis was performed, and fasting insulin concentration was positively associated with plasma osmolality in patients with NAFLD, after adjusting for gender, age, and BMI(r = 0.540, P = 0.046), but no correlation was noted in patients without NAFLD.CONCLUSION NAFLD is common in patients with hypopituitarism. Plasma osmolality and serum sodium levels of hypopituitary patients with cirrhosis are higher than those of subjects with NAFLD, and fasting insulin concentration is positively associated with plasma osmolality in patients with NAFLD, which suggests that hyperosmolality might be a contributor to the worsening of NAFLD in hypopituitary patients.

Cellular physiological approach for treatment of gastric cancer

Recent studies show that ion channels/transporters play important roles in fundamental cellular functions that would be involved in the cancer process. We review the evidence for their expression and functioning in human gastric cancer (GC), and evaluate the potential of cellular physiological approach in clinical management. Various types of ion channels, such as voltage-gated K+ channels, intracellular Cl- channels and transient receptor potential channels have been found to express in GC cells and tissues, and to control cell cycles. With regard to water channels, aquaporin 3 and 5 play an important role in the progression of GC. Regulators of intracellular pH, such as anion exchanger, sodium-hydrogen exchanger, vacuolar H+-ATPases and carbonic anhydrases are also involved in tumorigenesis of GC. Their pharmacological manipulation and gene silencing affect cellular behaviours, suggesting their potential as therapeutic targets for GC. Our studies indicate the intracellular Cl- concentration could act as a mediator of cellular signaling and control cell cycle progression in GC cells. Further, we demonstrate the cytocidal effects of hypotonic shock on GC cells, and indicate that the blockade of Cl- channels/transporters enhances these effects by inhibiting regulatory volume decrease. A deeper understanding of molecular mechanisms may lead to the discovery of these cellular physiological approaches as a novel therapeutic strategy for GC.

Changes in growth and osmoregulation during acclimation to saltwater in juvenile Amur sturgeon Acipenser schrenckii

We evaluated the ability of juvenile Amur sturgeon (Acipenser schrenckii) to osmoregulate and grow in saltwater. Hatchery-reared juveniles (mean weight 106.8 g, 5-month old) were transferred from freshwater to 10, 20, and 25 salinity saltwater over a period of 20 d. We measured the growth, serum osmolality, ion concentrations, and Na+/K+-ATPase activity. In addition, we prepared samples of gill tissue to quantify morphological changes in gill ultrastructure. Rearing in up to 25 saltwater for 30 d had no significant effect on growth. Similarly, serum osmolality and ion concentrations were similar to levels reported in other teleosts following acclimation to saltwater. Serum osmolality and Na+, Cl- concentrations increased significantly with the initial increase in salinity. Afterwards, levels tended to stabilize and then decrease. Serum K+ levels did not change during acclimation to saltwater. Gill Na+/K+-ATPase activity increased initially as salinity was increased. However, the activity later decreased and, finally stabilized at 3.7±0.1 μmol Pi/mg·prot·h in 25 saltwater (1.6 times higher than the level in those in freshwater). In fish that were held only in freshwater, the chloride cells were located in the interlamellar regions of the filament and at the base of the lamella. Following acclimation to 25 saltwater for 30 d, the number and size of chloride cells increased significantly. Our results suggest that juvenile Amur sturgeon is able to tolerate, and grow in, relatively high concentrations of saltwater.

Pathophysiology of Hypertrophic Pyloric Stenosis Revisited: The Use of Isotonic Fluid for Preoperative Infusion Therapy Is Supported

Background: The aim of this study was to elucidate the preoperative clinical and biochemical profile of infants with IHPS to optimize infusion therapy. Patients and Method: We retrospectively analyzed data from 56 infants who were operated for IHPS. Our study includes growth and laboratory data prior to the initiation of therapy. Results: Median duration of propulsive vomiting was 4 d;the median age was 37 d (18 - 108), and the median body weight was 3840 g (2760 -5900). Metabolic alkalosis (MAlk) with a pH of 7.45 ± 0.06 and an stHCO3- of 28.7 ± 4.5 mmol/l was found. In a subgroup of the infants, negative base excess (BE) was observed. The sodium concentration was normal or reduced (mean/median of 137 mmol/l). There was a strong negative correlation between stHCO3- and K+. The carbon dioxide partial pressure tended to increase (5.72 ± 0.84 kPa). Calculations of osmolality revealed a normal osmolarity. Hypoglycemia did not occur. The creatinine clearance according to the Schwartz formula remained at a normal level (85.3 ± 24.3 ml/min/1.73 m2). Discussion: The presented case series is characterized by a short duration of preoperative vomiting. MAlk can be classified as a chloride deficiency syndrome. It is accompanied by normo- or hyponatremic dehydration with normal osmolality. Partial respiratory compensation occurred. A normal creatinine clearance indicated good glomerular renal function. Conclusion: The presented study supports the use of an isotonic infusion fluid with a low glucose concentration for preoperative infusion therapy.

A EPC Approach to the Residual Water in Erythrocytes

A novel approach has been developed to determine the amount of residual water in human erythrocyte at room temperature by electronic particle counter. Nacl solutions of 13 osmolalities were prepared and the equilibrium cell volumes in which were measured one by one.The isotonic volume, V0, was obtained under the isotonic condition. The mean RBC volumes of 5 donors at each osmolality were fitted according to Boyle van’t Hoff relationship, and the osmotically inactive volume, Vb, of erythrocyte was then determined. The results show that Vb50% V0. More importantly, the final cell volume with regard to the solution of the highest concentration found to be kept at about 0.5 V0. The difference between these two volumes is unconspicuous. According to the published data that non-water volume of human erythrocyte is about 28.3% of its isotonic volume, residual water of human erythrocyte can be gained by subtracting V dry from Vf, that is V rw =21.7% V0. Then it was concluded that the residual water of human lays in 2 states, one is bound water, and the other is free water.

Osmol gap method for the detection of diethylene glycol in human serum

BACKGROUND： Measurement of the osmol gap （OG） is a technique that is used frequently in toxic alcohol poisonings （ethylene glycol （EG） and methanol） as a rapid means to estimate exposure, and can be performed in virtually all hospital laboratories. The value of the OG has not been previously evaluated for diethylene glycol （DEG） exposures. The primary objective of this study was to evaluate the utility of the OG in estimating DEG serum concentrations using the most common formula that is currently used for estimating methanol, ethanol, and ethylene glycol concentrations.METHODS： This was a controlled laboratory investigation using serum samples individually spiked with a known quantity of toxic alcohol compared to no toxic alcohol. Test samples were spiked with ethanol, DEG, EG, and methanol. Serum chemistries and osmolality and osmolarity were determined, and the OG was determined for each specimen.RESULTS： The percent error of estimating DEG concentrations of 26.3% was similar to the mean percent error for estimating other alcohol concentrations, 30.5%±5.6% （P〉0.05, 95% confidence interval 16.7%-44.3%）.CONCLUSION： The severity of metabolic effects associated with DEG and the need to appropriately determine rescue treatments mandate early detection of significant exposures for effective triage and patient management. Our results indicate that the percent error of the osmol gap method for estimating DEG concentration is similar to that of other toxic alcohols; this simple technique could be a valuable clinical tool, since quantitative DEG analysis is rarely available.

Physiological response of the razor clam Sinonovacula constricta exposed to hyposalinity stress

The razor clam Sinonovacula constricta is an economically important bivalve species in China,which inhabits the mudflat of intertidal and estuaries areas and frequently suffers the low salinity stress due to heavy rain events.The present study investigated the effects of hyposalinity stress(salinity 10,5,3,and 1)on osmoregulation and haemolymph microbiota in S.constricta after 7 days of exposure.The results showed that the survival rate of razor clams was only significantly reduced in the 1 ppt group compared to the control group(salinity 20)(P<0.05).Haemolymph osmolality in razor clams reduced significantly with decreasing salinities(P<0.05).Taurine,arginine,alanine and ornithine were the dominant free amino acids(FAAs)with higher contents in the haemolymph.Exposure to low salinities altered the composition of haemolymph FAAs,with alanine being the highest in the control group and taurine being the highest in the low salinity(LS)groups.Hyposalinity stress caused an increase in Na+/K+-ATPase(NKA)activity in gills,and histological analysis revealed severe hyperplasia in gills and a significant reduction in the length of gill filaments(P<0.05).The microbial community variation in the haemolymph assessed by 16S rRNA sequencing explains that bacterial communities was shifted under low salinity stress.At the genus level,the relative abundance of Marinobacterium,Marinomonas and Pseudomonas changed significantly under hyposalinity stress(P<0.05).These findings give further insight into the physiological responses and potential adaptation strategies of razor clams to hyposalinity stress and provide information for the development of inland low salinity culture.