The effects of alcohol withdrawal and acute doses of alcohol on the acid-base balance in mice and rats

While respiratory alkalosis has been reported to occur in human alcoholics during the withdrawal period, and may causally contribute to the expression of the withdrawal syndrome, we found no evidence of this in either alcohol physically-dependent mice (DBA/2J) or rats (Sprague-Dawley) as reflected in blood pH, plasma pCO2, or intracellular brain pH relative to pair-fed control (no alcohol) animals. The inhalation of atmospheres high in CO2 (5% and 15%), which would be expected to reverse a respiratory alkalotic state, had no effect on the expression of the withdrawal syndrome in alcohol-dependent mice. These results indicate that a withdrawal syndrome of considerable intensity can develop in mice and rats in the absence of an alkalotic state.     

Blood gas tensions and acid-base status in the fetal guinea-pig

To establish reference values for blood gas tensions in the fetal guinea-pig, blood was obtained by cardiac puncture or by puncture of the umbilical vein and analysed for pH, PCO2, PO2, haemoglobin concentration (Hb), oxyhaemoglobin saturation (SO2), and packed red cell volume. The measurements were made near term of pregnancy, on the 61st-66th day, and the dams were anaesthetized with diazepam and sodium pentobarbitone. In the umbilical venous blood, mean values for pH, PCO2, PO2, Hb and SO2, respectively, were 7.324, 45.1 mmHg, 29.5 mmHg, 8.8 mmol 1(-1), and 0.57 mol O2 per mol of haemoglobin monomer. The corresponding values for arterial blood from the heart were 7.265, 53.4 mmHg, 18.6 mmHg, 9.2 mmol 1(-1) and 0.25. Thus, blood gas tensions in the fetal guinea-pig are much closer to those of fetal primates and ungulates than has been recognized previously.     

Effect of exercise on acid-base status and ventilatory kinetics

OBJECTIVES: To study the clinical spectrum of an acute severe encephalopathy occurring in 2 patients after recovery from falciparum malaria infection and to compare it with the reported clinical features of the postmalaria neurological syndrome. DESIGN: Case report. SETTING: Tertiary care hospital. PATIENTS: Two patients presented with acute onset of fluctuating motor aphasia, severe generalized myoclonus, and postural tremor. Additional signs were cerebellar ataxia, and in 1 patient, generalized epileptic seizures. Magnetic resonance imaging of the brain revealed patchy white matter lesions in 1 patient. Clinically, the patients' conditions continued to worsen until corticosteroids were introduced, the use of which induced a rapid, albeit incomplete, recovery. CONCLUSIONS: We describe a new, severe variant of the still poorly defined postmalaria neurological syndrome. We propose a preliminary classification of this syndrome, according to its clinical characteristics, as follows: a mild or localized form, characterized by isolated cerebellar ataxia or postural tremor; a diffuse, but relatively mild encephalopathic form, characterized by acute confusion or epileptic seizures; and a severe, corticosteroid-responsive encephalopathy that is characterized by motor aphasia, generalized myoclonus, postural tremor, and cerebellar ataxia.     

Single and repetitive maternal glucocorticoid exposures reduce fetal growth in sheep

OBJECTIVE: We evaluated the effects of single or three repeated doses of maternal betamethasone on fetal growth at preterm and term delivery in sheep. STUDY DESIGN: Pregnant ewes were randomly assigned to receive one dose of 0.5 mg/kg betamethasone at 104 days' gestational age; three doses of betamethasone at 104, 111, and 118 days' gestational age; or saline for controls. Lambs were delivered at 125 days' (preterm) or at 145 days' (term) gestational age for assessments of fetal growth. RESULTS: The single betamethasone exposure at 104 days' gestational age caused symmetric growth retardation of 11% at 125 days' gestational age and 14% at term. The three-dose exposures decreased body weights by 25% in preterm lambs and by 19% at term. Organ protein and deoxyribonucleic acid per kilogram of body weight were selectively decreased in preterm lambs. At term the decreases in organ weight, protein, and deoxyribonucleic acid were proportionate to the decreased birth weight. CONCLUSION: One or three doses of maternal glucocorticoids begun at an early gestational age caused symmetric growth retardation in lambs delivered prematurely, and the decreased fetal size persisted to term.     

Effect of chronic hypoxemia on the regulation of nitric-oxide synthase in the fetal sheep brain

We undertook a prospective study to determine the type and distribution of foot and ankle snowboarding injuries. Reports of 3213 snowboarding injuries were collected from 12 Colorado ski resorts between 1988 and 1995. Of these, 491 (15.3%) were ankle injuries and 58 (1.8%) were foot injuries. Ankle injuries included 216 (44%) fractures and 255 (52%) sprains. Thirty-three (57%) of the foot injuries were fractures and 16 (28%) were sprains. The remaining injuries were soft tissue injuries, contusions, or abrasions. There was no significant correlation between boot type (soft, hybrid, or hard) and overall foot or ankle injury rate. There were significantly fewer ankle sprains in patients wearing hybrid boots and fewer fractures of the lateral process of the talus in patients wearing soft boots. An unexpectedly high number of fractures of the lateral process of the talus were noted. These 74 fractures represented 2.3% of all snowboarding injuries, 15% of all ankle injuries, and 34% of the ankle fractures. Many of these fractures are not visible on plain radiographs and require computed tomography imaging to be diagnosed. Diagnosis of this fracture pattern is paramount; the physician should be very suspicious of anterolateral ankle pain in the snowboarder, where subtle fractures that may require surgical intervention can be confused with anterior talofibular ligament sprains.     

Effects of maternal alcohol intake on fractal properties in human fetal breathing dynamics

Fractal methods have been found to be useful in characterizing biomedical signals. The use of fractal estimation requires the estimation of parameter H, which is directly related to the fractal dimension D. Here, we propose a new approach which is a combination of the wavelet transform and fractal estimators to characterize the human fetal breathing signals before and after the intake of two glasses of wine by a mother. This study was performed on 26 fetuses. The variances of the wavelet coefficients were estimated at each scale. The slope of the representation on a logarithmic plot from the scales 5 to 1 was found to be increased after alcohol intake. Our results suggested that fetal breathing rates have a rough structure before the alcohol intake and a smooth structure after alcohol intake.     

Acceleration of fetal head induced by vibration of maternal abdominal wall in sheep

OBJECTIVE: The human body is often exposed to significant vibration stress in the workplace, at home, and during recreational activities. The current study was designed to evaluate whether low- to midfrequency vibrations present at the extraabdominal wall would be attenuated across this wall and what the levels of exposure would be once these vibrations reached the fetal head. STUDY DESIGN: Four pregnant sheep were instrumented with acceleration transducers to obtain acceleration levels at the extraabdominal and intraabdominal walls and at the fetal head. Sine-wave vibration stimulation was applied over a frequency range of 3 to 150 Hz at a constant acceleration level of 2.5 m/sec2 (root-mean-square). RESULTS: Vibration of the extraabdominal wall resulted in a frequency-dependent rise in vibration levels at the intraabdominal wall, from 4% to 140% of the input level. At the fetal head a broad peak in response was noted between 6 and 12 Hz, but the overall levels never exceeded 4% of the input level. CONCLUSION: Fetal exposure to localized vibratory stimulation of the maternal abdomen is maximal in the range of 6 to 12 Hz.     

Effect of fetal alcohol exposure on adult symptoms of nicotine, alcohol, and drug dependence

The Tap (taxis toward peptides) receptor and the periplasmic dipeptide-binding protein (DBP) of Escherichia coli together mediate chemotactic responses to dipeptides. Tap is a low-abundance receptor. It is present in 5- to 10-fold-fewer copies than high-abundance receptors like Tar and Tsr. Cells expressing Tap as the sole receptor, even from a multicopy plasmid at 5- to 10-fold-overexpressed levels, do not generate sufficient clockwise (CW) signal to tumble and thus swim exclusively smoothly (run). To study the signaling properties of Tap in detail, we constructed reciprocal hybrids between Tap and Tar fused in the linker region between the periplasmic and cytoplasmic domains. The Tapr hybrid senses dipeptides and is a good CW-signal generator, whereas the Tarp hybrid senses aspartate but is a poor CW-signal generator. Thus, the poor CW signaling of Tap is a property of its cytoplasmic domain. Eighteen residues at the carboxyl terminus of high-abundance receptors, including the NWETF sequence that binds the CheR methylesterase, are missing in Tap. The Tart protein, created by removing these 18 residues from Tar, has diminished CW-signaling ability. The Tapl protein, made by adding the last 18 residues of Tar to the carboxyl terminus of Tap, also does not support CW flagellar rotation. However, Tart and Tapl cross-react well with antibody directed against the conserved cytoplasmic region of Tsr, whereas Tap does not cross-react with this antibody. Tap does cross-react, however, with antibody directed against the low-abundance chemoreceptor Trg. The hybrid, truncated, and extended receptors exhibit various levels of methylation. However, Tar and Tapl, which contain a consensus CheR-binding motif (NWETF) at their carboxyl termini, exhibit the highest basal levels of methylation, as expected. We conclude that no simple correlation exists between the abundance of a receptor, its methylation level, and its CW-signaling ability.     

The effect of segmental epidural analgesia on maternal and foetal acid-base balance, lactate, serum potassium and creatine phosphokinase during labour

Maternal and foetal acid-base balance, PaO2, lactate, potassium and creatine phosphokinase (CPK) were studied during the course of 28 induced labours. Every second mother received segmental epidural analgesia during the first stage of labour (epidural group), while the remaining mothers (who were given pethidine for pain relief, if necessary) acted as a control group. In the epidural group the patients had only minimal changes in acid-base balance and lactate concentration during the first stage. During the second stage lactate concentration increased. In the control group, on the other hand, the acid-base balance showed signs of hyperventilation and lactic acid accumulation during the first stage. The potassium changes were quite minimal and were not significantly different between the groups. The CPK level did not change during labour, but 2 and 4 h after delivery it was significantly elevated in both groups. The foetal acid-base balance, potassium, lactate and PaO2 values revealed no differences between the groups at any time. The CPK level in umbilical venous blood was significantly higher in the epidural group.     

Effect of fetal thymectomy on IgG, IgM, and IgA concentrations in sheep

Serum concentrations of immunoglobulins (Ig) IgG, IgG, IgM, and IgA were compared for normal and thymectomized lambs. Fetal thymectomies were performed in utero from 55 to 67 days of gestation. High serum IgG, IgM, and IgA concentrations occurred in all lambs after they ingested colostrum; however, the concentration of these Ig, as measured by single radial immunodiffusion, decreased exponentially during the first 16 days after birth. The half-life values for IgG, IgM, and IgA during this period in both normal and thymectomized lambs were about 25, 6, and 2 days, respectively. Increasing amounts of IgG were not detected in the serums of either group until 1 month of age. At 64 to 128 days, significantly smaller quantities of IgG and IgG were found in thymectomized lambs, whereas concentrations of IgA and IgM were similar in both groups. The results indicate that the thymus may regulate production of IgG in sheep.     

Effect of chronic maternal methadone exposure on perinatal development

The effect of perinatal exposure to methadone on body growth and brain development was studied in rat. Female Sprague-Dawley albino rats received daily intraperitoneal injections of 5 mg/kg dl-methadone-HCl during gestation and lactation. Body weights were reduced in drug-treated mothers during gestation and the first 2 weeks of lactation. No differences in gestation time, litter size, or infant mortality were recorded, however methadone-treated offspring grew more slowly than controls. Weight deficits persisted in rats observed 5-1/2 weeks after cessationof drug exposure (group 1) and in animals continuing to receive daily interperitoneal injections of 5 mg/kg (group 2). From birth to day 21, brain weight and length, cerebral width and cerebellar weight and width were generally smaller in methadone-exposed rats. Brain measurements of group 1 and group 2 animals on day 60 revealed a reduction in brain and cerebellar weights and cerebral and cerebellar widths from control values. Brain:body weight and cerebellum:brain weight ratios were similar to controls. Analysis of these results indicates that maternal methadone treatment retards the growth of young rats and affects brain development.     

Effect of clenbuterol on endocrine status and nitrogen and energy balance in food-restricted rats

We administered clenbuterol as a dietary admixture (4 mg/kg diet) to three groups of male Wistar rats (n = 8) housed individually in metabolism cages and fed for 15 d at 110, 160, and 235% (ad libitum) of the estimated requirement for energy maintenance. Untreated groups at each level of energy intake and a baseline group were also included. In the diet-restricted rats, clenbuterol induced greater and more persistent increases in nitrogen balance, biological value, and net protein utilization than it did in the ad libitum-fed rats. Energy balance was increased by clenbuterol treatment in the diet-restricted rats, with no significant changes occurring in the ad libitum fed rats. Compared with untreated rats, clenbuterol reduced blood glucose in all diet groups and serum insulin in the ad libitum and the moderately restricted (160%) rats. Serum IGF-I was increased in the highly restricted (110%) rats. Corticosterone levels were increased by clenbuterol treatment in all diet groups. These results are consistent with previous results showing that clenbuterol can help improve growth, but they also show that clenbuterol can offset the effects of food restriction on protein and energy metabolism.     

Effect of microelements on formation of acids and ethyl alcohol by Saccharomyces carlsbergensis yeasts]

The effect of Fe, Zn, Mn, Pb, Al, Cu, and K on the synthesis of pyruvic, alpha-ketoglutaric and total volatile acids and ethanol was studied in the process of fermentation of 6 per cent maltose solution by Saccharomyces carlsbergensis 776. Experiments were conducted using techniques of their mathematical planning. Fe, Pb, and Mn at concentrations of 15.0, 0.5, and 1.5 mg/litre, respectively, had a positive effect on the synthesis of pyruvic acid whose concentration in the medium increased by 3.3 mg per 100 ml to become equal to 43.3 mg per 100 ml. Fe3+ at a concentration of 15 mg/litre had a negative effect on the synthesis of alpha-ketoglutaric acid. The synthesis of volatile acids depended on the presence of Fe, Zn, Pb, Al, and K. Fe and Al at concentrations of 15 mg/litre favoured the synthesis of volatile acids by 2.72 mg/litre. In the presence of Zn (1.5 mg/litre), Pb (0.5 mg/litre), and K (15 mg/litre), the content of volatile acids decreased by 4.48 mg/litre and became equal to 14.94 mg/litre. Zn at a concentration of 1.5 mg/litre inhibited it.