Long-term Effects of Dietary Anion-Cation Balance on Acid-Base Status and Bone Morphology in Reproducing Ewes

2003 ◽  
Vol 50 (10) ◽  
pp. 488-495 ◽  
Author(s):  
L. Espino ◽  
F. Guerrero ◽  
M. L. Suarez ◽  
G. Santamarina ◽  
A. Goicoa ◽  
...  
Keyword(s):  
Long Term Effects ◽  
Bone Morphology ◽  
Acid Base ◽  
Acid Base Status

The Effect of Long-Term Aerial Exposure on Heart Rate, Ventilation, Respiratory Gas Exchange and Acid-Base Status in the Crayfish Austropotamobius Pallipes

1981 ◽  
Vol 92 (1) ◽  
pp. 109-124
Author(s):  
E. W. TAYLOR ◽  
MICHÈLE G. WHEATLY
Keyword(s):  
Heart Rate ◽  
Lactic Acid ◽  
O2 Consumption ◽  
Aerial Exposure ◽  
Acid Base ◽  
Bicarbonate Buffer ◽  
Content Difference ◽  
Acid Base Status ◽  
Lactate Levels

1. When first removed into air, crayfish showed transient increases in heart rate (fH) and scaphognathite rate (fR) which rapidly recovered to submerged levels and were unchanged for 24 h. The rate of O2 consumption(Moo2) increased from an initially low level and was then maintained for 24 h in air at the same level as in settled submerged animals. 2. There was an initial acidosis in the haemolymph which was both respiratory and metabolic due to the accumulation of CO2 and lactate. Progressive compensation by elevation of the levels of bicarbonate buffer in the haemolymph and reduction of circulating lactate levels returned pH towards submerged levels after 24 h in air. 3. Exposure to air resulted in a marked internal hypoxia with haemolymph O2, tensions, both postbranchial Pa, oo2 and prebranchial Pv, oo2, remaining low throughout the period of exposure. The oxygen content or the haemolymph was initially reduced, with a - vOO2 content difference close to zero. Within 24 h both Ca, oo2 and Cv, OO2 had returned towards their levels in submerged animals. These changes are explained by the Bohr shift on the haemocyanin consequent upon the measured pH changes. 4. After 48 h in air, MO2 and fH were significantly reduced and ventilation became intermittent. There was a slight secondary acidosis, increase in lactic acid levels and reduction in a - vO2 content difference in the haemolymph. 5. When crayfish were returned to water after 24 h in air, MOO2, fHfR were initially elevated by disturbance and there was a period of hyperventilation. In the haemolymph there was an initial slight alkalosis, and an increase in Ca, OO2 lactic acid. All variables returned to their settled submerged levels within 8 h.

No Long-Term Effects of Ultrasound Therapy on Bioabsorbable Screw-Fixed Lateral Malleolar Fracture

2005 ◽  
Vol 94 (3) ◽  
pp. 239-242 ◽  
Author(s):  
L. Handolin ◽  
V. Kiljunen ◽  
I. Arnala ◽  
M. J. Kiuru ◽  
J. Pajarinen ◽  
...  
Keyword(s):  
Bone Mineral Density ◽  
Clinical Outcome ◽  
Bone Mineral ◽  
Ultrasound Therapy ◽  
Long Term Effects ◽  
Bone Morphology ◽  
Mineral Density ◽  
Bioabsorbable Screw ◽  
Malleolar Fractures

Background and Aims: The present study was initiated to evaluate the long-term effects of low-intensity ultrasound therapy on bioabsorbable screw-fixed lateral malleolar fractures, which has not been studied earlier. Patients and Methods: The study design was prospective, randomized, double-blinded, and placebo-controlled. Sixteen dislocated lateral malleolar fractures were fixed with one bioabsorbable self-reinforced poly-L-lactide screw. The patients used an ultrasound device 20 minutes daily for six weeks without knowing it was active (eight patients) or inactive (eight patients). The follow-up time was 18 months. The radiological bone morphology was assessed by multidetector computed tomography (MDCT) scans, the bone mineral density by dual-energy X-ray absorptiometry scans, and the clinical outcome by Olerud-Molander scoring and clinical examination of the ankle. Results: The MDCT scans revealed that all fractures were fully healed, and no differences were observed in radiological bone morphology at the fracture site. The bone mineral density of the fractured lateral malleolus tended to increase slightly during the 18-month follow-up, the increase being symmetrical in both groups. No differences were observed in the clinical outcome or Olerud-Molander scores. Conclusions: The six-week low-intensity ultrasound therapy had no effect on radiological bone morphology, bone mineral density or clinical outcome in bioabsorbable screw-fixed lateral malleolar fractures 18 months after the injury.

scholarly journals Effects of sevoflurane and clonidine on acid base status and long-term emotional and cognitive outcomes in spontaneously breathing rat pups

PLoS ONE ◽  
2017 ◽  
Vol 12 (3) ◽  
pp. e0173969 ◽  
Author(s):  
Nicole Almenrader ◽  
Paola Colucci ◽  
Valentina De Castro ◽  
Daniela Valeri ◽  
Maura Palmery ◽  
...  
Keyword(s):  
Cognitive Outcomes ◽  
Acid Base ◽  
Rat Pups ◽  
Acid Base Status ◽  
Spontaneously Breathing

Acid—Base Status in Dogs during Long Term Anaesthesia

1975 ◽  
Vol 80 (2) ◽  
pp. 77-82 ◽  
Author(s):  
B. Danielson ◽  
G. Grängsjö ◽  
B. Karlmark ◽  
H. R. Ulfendahl ◽  
M. Wolgast
Keyword(s):  
Acid Base ◽  
Acid Base Status

scholarly journals Acid-base status and cardiovascular function in mink (Mustela vison) anaesthetized with ketamine/midazolam

1996 ◽  
Vol 30 (1) ◽  
pp. 55-66 ◽  
Author(s):  
S. Wamberg ◽  
P. Svendsen ◽  
B. Johansen
Keyword(s):  
Heart Rate ◽  
Sodium Bicarbonate ◽  
Isotonic Saline ◽  
Cardiovascular Function ◽  
Spontaneous Respiration ◽  
Acid Base ◽  
Arterial Blood ◽  
Intravenous Solution ◽  
Acid Base Status

Heart rate, arterial blood pressure and blood acid-base status were determined in 18 adult female mink (mean (±SEM)body weight 1052±34 g)during long-term anaesthesia with either controlled ventilation ( n=12) or spontaneous respiration ( n=6) Surgical anaesthesia was induced by intramuscular injection of ketamine hydrochloride (Ketaminol Vet®, 40.0±1.7mg/kg) and midazolam hydrochloride (Dormicum® 2.8±0.1 mg/kg) and maintained for at least 5 h by continuous intravenous infusion of this drug combination in 0.9% saline. For all animals, the mean rates of infusion of ketamine and midazolam were 48.4±1.6 and 1.61±0.12 mg/h, respectively. Following continuous infusion of the anaesthetics in isotonic saline, at a rate of 20 ml/h, a moderate 'dilution acidosis' developed, which could be corrected by replacement of part of the saline with sodium bicarbonate to a final concentration of approximately 25 mmol NaHCO3 per litre. However, when the animals were allowed to breathe spontaneously, an increase in heart rate and a combined respiratory and metabolic acidosis occurred, due to severe respiratory depression. Apart from these effects and a few cases of increased salivation, no adverse effects over time were observed on the arterial blood acid-base status and cardiovascular function of the animals during ketamine/midazolam anaesthesia. It is concluded that the procedure described for long-term anaesthesia in mink is convenient and safe for acute physiological experiments in this species, provided normal body temperature and pulmonary gas exchange is sufficiently maintained. Thus, the need for an adequately controlled artificial ventilation is strongly emphasized. Finally, a proposal for the composition of an intravenous solution, containing ketamine and midazolam hydrochloride, and sodium bicarbonate in saline, suitable for long-term anaesthesia in adult mink is presented.

scholarly journals The importance of metabolism in acid–base regulation and acid–base methodology

1989 ◽  
Vol 67 (12) ◽  
pp. 3005-3017 ◽  
Author(s):  
Hans-Otto Pörtner
Keyword(s):  
Integrated Control ◽  
Feedback Regulation ◽  
Urea Synthesis ◽  
Acid Base ◽  
Base Parameters ◽  
Recent Developments ◽  
Acid Base Status ◽  
The Relationship ◽  
Aerobic And Anaerobic

Metabolism not only affects the acid–base status of an animal by means of proton stoichiometries but, by feedback regulation, acid–base parameters (pH, [Formula: see text], bicarbonate) influence metabolic rates and the pathways used. This leads to a significant contribution of metabolism to acid–base regulation under both aerobic and anaerobic conditions. The relationship between amino acid metabolism, urea synthesis, and [Formula: see text] excretion is discussed as an example important for steady-state metabolic acid–base regulation during aerobiosis. Generally, acid–base relevant metabolism may be regulated through the effect of acid–base disturbances on hormonal mediation, allosteric modulation of enzyme proteins, pH optima, and the levels of substrates or products, some of these being acid–base relevant substances like bicarbonate, CO2, inorganic phosphate, and NH3. During functional or environmental anaerobiosis the same relationships prevail. Metabolic proton accumulation is counterbalanced by phosphagen depletion and ammonia accumulation in adenylate catabolism. In addition, in integrated control of metabolic and acid–base status, long-term (mitochondrial) anaerobiosis leads to reductions in metabolic rate and increased removal of acidic groups. The importance of metabolic processes in acid–base methodology is discussed in terms of traditional concepts and recent developments.

scholarly journals Long Term Effects of Forest Liming on the Acid-Base Budget

2021 ◽  
Vol 11 (3) ◽  
pp. 955
Author(s):  
Martin Greve ◽  
Joachim Block ◽  
Gebhard Schüler ◽  
Willy Werner
Keyword(s):  
Base Cation ◽  
Mineral Weathering ◽  
Seepage Water ◽  
Negative Consequences ◽  
Long Term Effects ◽  
Acid Base ◽  
Nitrogen Emissions ◽  
Acid Load ◽  
Forest Liming

In Rhineland-Palatinate (Germany), a high percentage of the forest area is located on poor soils with low buffering capacity. Extensive liming applications were performed to compensate for the negative consequences of acid deposition. In 1988, three experimental sites with untreated control plots and different liming treatments were established in coniferous stands to investigate the effectiveness of liming on acidification and its effect on forest ecosystems. Measuring deposition and seepage waters for 24 years allowed for calculating long-term acid-base budgets. The original approach was expanded by data from a detailed sampling of the forest stand and mineral weathering rates. Without liming, the acid load exceeded the buffer capacity by base cation release from silicate weathering during the whole observation period. As a result, there was a high release of aluminum. After liming seepage water output of organic anions, nitrate and sulfate increased in some cases, leading to a higher acid load. However, the carbonates of dolomitic limestone compensated for a higher acid load, resulting in less aluminum released compared to the control plots. Until sulfate output by seepage water declines and nitrogen emissions are reduced, liming and restricted biomass harvesting are required for forest stands on base poor soils to prevent further acidification, decline of nutrient stocks, and the destruction of clay minerals.

scholarly journals Acid-base regulation, metabolism and energetics in sipunculus nudus as a function of ambient carbon dioxide level

1998 ◽  
Vol 201 (1) ◽  
pp. 43-55 ◽  
Author(s):  
H O Pörtner ◽  
A Reipschläger ◽  
N Heisler
Keyword(s):  
Ammonium Excretion ◽  
Ion Transfer ◽  
Energy Status ◽  
Intracellular Acidosis ◽  
Acid Base ◽  
Sipunculus Nudus ◽  
Acid Base Status ◽  
Net Release

Changes in the rates of oxygen consumption and ammonium excretion, in intra- and extracellular acid-base status and in the rate of H+-equivalent ion transfer between animals and ambient water were measured during environmental hypercapnia in the peanut worm Sipunculus nudus. During exposure to 1 % CO2 in air, intracellular and coelomic plasma PCO2 values rose to levels above those expected from the increase in ambient CO2 tension. Simultaneously, coelomic plasma PO2 was reduced below control values. The rise in PCO2 also induced a fall in intra- and extracellular pH, but intracellular pH was rapidly and completely restored. This was achieved during the early period of hypercapnia at the expense of a non-respiratory increase in the extracellular acidosis. The pH of the extracellular space was only partially compensated (by 37 %) during long-term hypercapnia. The net release of basic equivalents under control conditions turned to a net release of protons to the ambient water before a net, albeit reduced, rate of base release was re-established after a new steady state had been achieved with respect to acid-base parameters. Hypercapnia also affected the mode and rate of metabolism. It caused the rate of oxygen consumption to fall, whereas the rate of ammonium excretion remained constant or even increased, reflecting a reduction of the O/N ratio in both cases. The transient intracellular acidosis preceded a depletion of the phosphagen phospho-l-arginine, an accumulation of free ADP and a decrease in the level of Gibbs free energy change of ATP hydrolysis, before replenishment of phosphagen and restoration of pHi and energy status occurred in parallel. In conclusion, long-term hypercapnia in vivo causes metabolic depression, a parallel shift in acid-base status and increased gas partial pressure gradients, which are related to a reduction in ventilatory activity. The steady-state rise in H+-equivalent ion transfer to the environment reflects an increased rate of production of protons by metabolism. This observation and the reduction of the O/N ratio suggest that a shift to protein/amino acid catabolism has taken place. Metabolic depression prevails, with completely compensated intracellular acidosis during long-term hypercapnia eliminating intracellular pH as a significant factor in the regulation of metabolic rate in vivo. Fluctuating levels of the phosphagen, of free ADP and in the ATP free energy change values independent of pH are interpreted as being correlated with oscillating ATP turnover rates during early hypercapnia and as reflecting a tight coupling of ATP turnover and energy status via the level of free ADP.

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