scholarly journals THE EFFECTS OF SEASONAL VARIATIONS IN TEMPERATURE ON EXTRACELLULAR ACID-BASE STATUS IN A WILD POPULATION OF THE CRAYFISH AUSTROPOTAMOBIUS PALLIPES

1993 ◽  
Vol 181 (1) ◽  
pp. 295-311
Author(s):  
N. M. Whiteley ◽  
E. W. Taylor
Keyword(s):  
Seasonal Variations ◽  
Low Temperatures ◽  
Seasonal Changes ◽  
Wild Population ◽  
Late Summer ◽  
Co2 Solubility ◽  
Acid Base ◽  
Austropotamobius Pallipes ◽  
Ph Values ◽  
Acid Base Status

Between February 1990 and February 1991, a wild population of Austropotamobius pallipes (L.) inhabiting a large, shallow, freshwater pool in Staffordshire, central England, experienced environmental fluctuations in water temperature (1–21°C) and pH (8.2-9.5). Moulting was seasonal, with crayfish entering pre- and postmoult between May and August. Haemolymph pHa levels declined in the spring when temperatures increased from 8 to 18°C (deltapH/deltat=−0.013 pH units°C-1). This decrease was accompanied by a fall in [HCO3-] (of 4.12 mmol l-1) and [lactate] (of 4.71 mmol l-1) and a premoult elevation in PCO2 to 0.59 kPa. After ecdysis, when water temperatures and pH were at their maxima, pHa levels increased, they continued to increase as temperature fell in late summer, reaching 7.97 in intermoult crayfish at 13°C during September. This increase was accompanied by a decrease in PCO2 to 0.22 kPa at constant [HCO3-] (5–6 mmol l-1). Between September (13°C) and October (11°C) pHa fell to 7.87 with an elevation in PCO2 (of 0.18 kPa) and [lactate] (of 1.84 mmol l-1). As temperature continued to decrease (11–1°C), pHa remained unchanged despite an elevation in [HCO3-] by 2.4 mmol l-1 at constant PCO2. A mechanism accounting for the unvarying haemolymph pH values at low temperatures is proposed, stressing the importance of temperature-related seasonal changes in CO2 solubility and measured values for pK1′ in addition to adjustments in [HCO3-] and PCO2. These were apparently unaffected by changes in collecting and holding protocols.

scholarly journals Effects of External Acidification on the Blood Acid-Base Status and Ion Concentrations of Lamprey

1988 ◽  
Vol 136 (1) ◽  
pp. 351-361
Author(s):  
LEONA MATTSOFF ◽  
MIKKO NIKINMAA
Keyword(s):  
High Sensitivity ◽  
Co2 Concentration ◽  
Acid Base ◽  
Ion Concentrations ◽  
Ph Response ◽  
Ph Values ◽  
Blood Ph ◽  
Acid Base Status ◽  
The Difference ◽  
K Concentration

We studied the effects of acute external acidification on the acid-base status and plasma and red cell ion concentrations of lampreys. Mortality was observed within 24 h at pH5 and especially at pH4. The main reason for the high sensitivity of lampreys to acid water appears to be the large drop in blood pH: 0.6 and 0.8 units after 24 h at pH5 and pH4, respectively. The drop of plasma pH is much larger than in teleost fishes exposed to similar pH values. The difference in the plasma pH response between lampreys and teleosts probably results from the low buffering capacity of lamprey blood, since red cells cannot participate in buffering extracellular acid loads. Acidification also caused a decrease in both Na+ and C− concentrations and an elevation in K+ concentration of plasma. The drop in plasma Na+ concentration occurred faster than the drop in plasma Cl− concentration which, in turn, coincided with the decrease in total CO2 concentration of the blood.

Electrochemical heterogeneity of the cochlear endolymph: effect of acetazolamide

1984 ◽  
Vol 246 (1) ◽  
pp. F47-F53 ◽  
Author(s):  
O. Sterkers ◽  
G. Saumon ◽  
P. Tran Ba Huy ◽  
E. Ferrary ◽  
C. Amiel
Keyword(s):  
Inner Ear ◽  
Endocochlear Potential ◽  
Electrochemical Gradient ◽  
Acid Base ◽  
Basal Turn ◽  
Ph Values ◽  
Blood Ph ◽  
Acid Base Status ◽  
Electrochemical Heterogeneity ◽  
Inner Ear Fluids

The electrochemical composition of endolymph (EL) of two adjacent cochlear turns was studied in anesthetized rats. Differences in [K]EL, [Cl]EL, and endocochlear potential (EP) were found between the basal turn (165.6 +/- 3.0 mM, n = 14; 144.6 +/- 2.1 mM, n = 14;96.6 +/- 1.9 mV, n = 5, respectively) and the middle turn (155.7 +/- 2.5 mM, n = 15; 133.2 +/- 1.5 mM, n = 15; 87.0 +/- 1.6 mV, n = 6, respectively). The pH values of inner ear fluids were evaluated with 5,5-dimethyloxazolidine-2,4-dione: EL pH of either turn was not different from blood and perilymph (PL) pH. Acetazolamide (40 mg X kg body wt-1) reduced EP and [Cl]EL at each turn by about 20 and 6%, respectively, but [K]EL was unchanged. The electrochemical differences between the two turns persisted. Acetazolamide produced a 0.2-unit decrease in blood pH while the pH values of EL and PL remained unchanged. These results suggest the existence of an electrochemical gradient within EL from the base to the apex of the cochlea involving K+ and Cl- concentrations. H+ and HCO-3 do not appear to participate in this gradient, and the acid-base status in EL could be maintained both by active H+ transport into EL and by HCO-3 formation in the cochlear epithelium.

scholarly journals Analysis of Haemolymph and Muscle Acid-Base Status During Aerial Exposure in the Crayfish Austropotamobius Pallipes

1988 ◽  
Vol 134 (1) ◽  
pp. 409-422 ◽  
Author(s):  
R. TYLER-JONES ◽  
E. W. TAYLOR
Keyword(s):  
Base Excess ◽  
Abdominal Muscle ◽  
Internal Source ◽  
Intracellular Acidosis ◽  
Aerial Exposure ◽  
Acid Base ◽  
Bicarbonate Buffer ◽  
Air Exposure ◽  
Austropotamobius Pallipes ◽  
Acid Base Status

Exposure of the crayfish Austropotamobius pallipes to air resulted in an acidosis in the postbranchial haemolymph (pHa) and the abdominal muscle. The haemolymph acidosis was subsequently compensated and, after 24 h in air, pHa had returned to the settled, submerged value. The intracellular acidosis remained uncompensated throughout the period of aerial exposure. When crayfish were first removed into air, lactate concentrations in the haemolymph and abdominal muscle increased substantially. After 24 h in air lactate concentrations in both compartments had returned towards submerged levels. Possibilities for the fate of lactate are discussed. Re-analysis of haemolymph acid-base data for crayfish exposed to air (Taylor & Wheatly, 1981) revealed discrepancies between observed and expected base excess. Initially these may arise from exchanges of H+ or HCO3− with other compartments. During long-term air exposure, the removal of lactate from the haemolymph and an independent accumulation of base, probably from the mobilization of an internal source of bicarbonate buffer, result in the observed pH compensation. Determination of base excess for the changes in abdominal muscle acid-base status after 3 h of exposure to air corroborated the results of the haemolymph analysis, suggesting a retention of H+ despite the efflux of lactate.

Seasonal changes in blood oxygen transport and acid–base status in the tegu lizard, Tupinambis merianae

2004 ◽  
Vol 140 (2) ◽  
pp. 197-208 ◽  
Author(s):  
Denis V. Andrade ◽  
Simone P. Brito ◽  
Luı́s Felipe Toledo ◽  
Augusto S. Abe
Keyword(s):  
Oxygen Transport ◽  
Seasonal Changes ◽  
Blood Oxygen ◽  
Acid Base ◽  
Acid Base Status ◽  
Tupinambis Merianae ◽  
Tegu Lizard

The Effect of Acidosis on Lactate Removal by the Perfused Rat Kidney

1976 ◽  
Vol 50 (3) ◽  
pp. 185-194 ◽  
Author(s):  
J. Yudkin ◽  
R. D. Cohen
Keyword(s):  
Rat Kidney ◽  
Acid Base ◽  
Ph Values ◽  
Constant Rate ◽  
Perfused Rat Kidney ◽  
Lactate Removal ◽  
Acid Base Status ◽  
Glucose Output ◽  
Normal Acid

1. The isolated perfused kidneys of fed rats in normal acid-base status showed a constant rate of lactate removal from the perfusate between 5 and 90 min of perfusion at a perfusate pH of 7·4–7·5. 2. Lactate removal by kidneys of rats in normal acid-base status was stimulated within 30 min by a reduction in perfusate pH to 7·1–7·2, but depressed when perfusate pH was reduced further. 3. Kidneys taken from rats previously made acidotic and perfused with media of various pH values showed a progressive fall in the rate of lactate removal during the perfusion. 4. Glucose output by the kidneys of rats in normal acid—base status perfused with lactate as substrate was not affected by an alteration in perfusate pH. The kidneys of acidotic rats generally showed an increased rate of glucose output compared with those of control rats.

scholarly journals Log-Jam in Acid-Base Education and Investigation: Why Make it so Difficult?

1998 ◽  
Vol 35 (1) ◽  
pp. 85-93
Author(s):  
James Hooper ◽  
William J Marshall ◽  
Arthur L Miller
Keyword(s):  
Medical Students ◽  
Acid Base ◽  
Logical Interpretation ◽  
Ph Values ◽  
Safe Management ◽  
Acid Base Status ◽  
Base Data ◽  
Base Education

Medical students frequently have difficulty in interpreting acid-base data particularly when pH values are used. The difficulty persists when students qualify and has implications for the safe management of patients who require investigation of acid-base status. Simplification of tuition is required together with a change of practice in the reporting of acid-base data by the laboratories. To improve understanding, we recommend that the teaching and reporting of acid-base status should be changed to use [H+] instead of pH, and a greater emphasis placed on the logical interpretation of primary measurements—that is [H+] and PCO2-with less reliance on derived variables.

To Manage Infantile Hypertrophic Pyloric Stenosis by "Double-Y Pyloromyotomy" is a better Surgical Approach

2014 ◽  
Vol 1 (2) ◽  
pp. 143-147
Author(s):  
Md. Ansar Ali ◽  
Kaniz Hasina ◽  
Shahnoor Islam ◽  
Md. Ashraf Ul Huq ◽  
Md. Mahbub-Ul Alam ◽  
...  
Keyword(s):  
Weight Gain ◽  
Pyloric Stenosis ◽  
Hypertrophic Pyloric Stenosis ◽  
Treatment Modalities ◽  
Infantile Hypertrophic Pyloric Stenosis ◽  
Postoperative Vomiting ◽  
Acid Base ◽  
Feeding Regimes ◽  
Acid Base Status ◽  
Postoperative Feeding

Background: Different treatment modalities and procedures have been tried for the management of infantile hypertrophic pyloric stenosis. But surgery remains the mainstay for management of IHPS. Ramstedt’s pyloromyotomy was described almost over a hundred years ago and to date remains the surgical technique of choice. An alternative and better technique is the double-Y pyloromyotomy, which offer better results for management of this common condition.Methods: A prospective comparative interventional study of 40 patients with IHPS was carried out over a period of 2 years from July 2008 to July 2010. The patients were divided into 2 equal groups of 20 patients in each. The study was designed that all patients selected for study were optimized preoperatively regarding to hydration, acid-base status and electrolytes imbalance. All surgeries were performed after obtaining informed consent. Standard preoperative preparation and postoperative feeding regimes were used. The patients were operated on an alternate basis, i.e., one patient by Double-Y Pyloromyotomy(DY) and the next by aRamstedt’s Pyloromyotomy (RP). Data on patient demographics, operative time, anesthesia complications, postoperative complications including vomiting and weight gain were collected. Patients were followed up for a period of 3 months postoperatively. Statistical assessments were done by using t test.Results: From July 2008 through July 2010, fourty patients were finally analyzed for this study. Any statistical differences were observed in patient population regarding age, sex, weight at presentation, symptoms and clinical condition including electrolytes imbalance and acid-base status were recorded. Significant differences were found in postoperative vomiting and weight gain. Data of post operative vomiting and weight gain in both groups were collected. Vomiting in double-Y(DY) pyloromyotomy group (1.21 ± 0.45days) vs Ramstedt’s pyloromyotomy (RP) group(3.03 ± 0.37days) p= 0.0001.Weight gain after 1st 10 days DY vs RP is ( 298 ± 57.94 gm vs193±19.8 gm p=0.0014), after 1 month (676.67±149.84 gm vs 466.67 ± 127.71 gm, p=0.0001), after 2months (741.33± 278.74 gm vs 490±80.62 gm, p=0.002) and after 3 months (582±36.01gm vs 453.33±51.64 gm, p=0.0001).No long-term complications were reported and no re-do yloromyotomy was needed.Conclusion: The double-Y pyloromyotomy seems to be a better technique for the surgical management of IHPS. It may offer a better functional outcome in term of postoperative vomiting and weight gain.DOI: http://dx.doi.org/10.3329/jpsb.v1i2.19532

Synthesis, Characterization and Thermal studies of Novel Organomercury Driven from Sulfa Drugs Part 1

2011 ◽  
Vol 7 (2) ◽  
pp. 1338-1347
Author(s):  
Tarek Ali Fahad ◽  
Shaker.A.N. AL-Jadaan
Keyword(s):  
Thermal Decomposition ◽  
Thermal Behavior ◽  
1H Nmr ◽  
Elemental Analysis ◽  
Thermal Studies ◽  
Spectroscopic Techniques ◽  
Sulfa Drugs ◽  
Acid Base ◽  
Ph Values ◽  
Multi Stage

Two new heterocyclic Organmercury compounds   were prepared from the reaction of Sulfamethaxazole and Sulfadiazine with 4-acetaminophenol as a coupler and separated as solids with characteristic colors. these compounds were characterized by F.T.IR-spectroscopy 1H-NMR , Micro-elemental Analysis and UV-Vis spectroscopic techniques . The work involves a study of acid – base properties compounds at different pH values, the ionization and protonation constants were calculated. The thermal behavior of these two compounds   were investigated on the basis of thermogravimetric (TGA) and differential thermogravimetric (DTG) analyses, Thermal decomposition of these compounds is multi-stage processes.

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