0902 The Use Of Auto-titrating Continuous Positive Airway Pressure (auto Cpap) For Obstructive Sleep Apnea In Children With Neurological Disorder

Introduction

Multiple studies have demonstrated the effectiveness of auto-titrating continuous positive airway pressure (auto CPAP) in the adult population, but there is limited literature on the use of auto CPAP in the pediatric population. Specifically, the use of auto CPAP in children with neurological disorder(s) has not been established. Thus, we conducted a study to review the use of auto CPAP in children ages 18 years old and younger with Obstructive Sleep Apnea Syndrome (OSAS) and associated neurological disorder to document its effectiveness, adverse events and outcomes of its use.

Methods

A retrospective chart review was performed on patients 18 yo and younger diagnosed with OSAS and associated neurological disorder(s) who have good compliance with auto CPAP use. Good compliance was defined as >4 hours/night and >20/30 days of auto CPAP use. Compliance from the most recent 30 days was downloaded.

Results

5 children met our criteria for inclusion, with a mean age of 11 years (6-18 years old). All had initial baseline sleep studies performed without PAP titration polysomnography. Associated neurological disorders were cerebral palsy, Arnold Chiari Malformation, seizure disorder and intellectual disability. The average length of use of auto CPAP was 4 months. Auto CPAP was used on average of 24/30 nights, with a mean of 7.35 hours/night. The mean baseline obstructive apnea-hypopnea (OAHI) index was 42 (8.2-94.4). The mean AHI on a 30 day download report showed a mean decrease in AHI to 2.9 (0.5-5.2) while on auto CPAP. Review of patient charts did not reveal any adverse outcomes associated with the use of auto CPAP in these patients.

Conclusion

This study showed that auto CPAP significantly improved the AHI in pediatric patients treated for OSA with associated neurological disorder. There were no reported adverse outcomes. Further research is needed to establish the effectiveness and safety of auto CPAP use in the pediatric population, specifically those with neurological disorder. The use of auto CPAP will help decrease the wait time for treatment in children with OSA. These patients can use auto CPAP while waiting for a titration study and for long term use.

Support

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Assessment of new application system in Portuguese patients with relapsing-remitting multiple sclerosis

OBJECTIVE

To evaluate the satisfaction level of multiple sclerosis (MS) patients treated with interferon beta-1b (IFNbeta-1b, Betaferon*) using a newly developed application system compared to their currently used application system.

METHODS

A survey was conducted in Portugal in patients treated with IFNbeta-1b for relapsing-remitting MS with the Betaject or Betaject Lite autoinjector. Nurses demonstrated the new application system and supervised the first injection. Patients rated their overall satisfaction retrospectively with their current application system and prospectively after the first, the seventh and the 15th injection with the newly developed application system. Additionally, the ease of use was evaluated for both application systems using a questionnaire consisting of 13 questions. Responses were compiled and descriptive analyses performed.

RESULTS

A total of 249 patients evaluated the current and the new system after the first, 235 after the seventh and 174 after the 15th injection. The satisfaction level was high with the current system (70.3%, 'satisfied' or 'very satisfied'). However, compared with the current system, more patients were either 'satisfied' or 'very satisfied' (98%) with the new system after first injection. Only a minority of patients rated 'somewhat satisfied': 2.0% after the first, 8.6% after the seventh, and 4.4% after the 15th injection. Increased overall satisfaction level ('satisfied' or 'very satisfied') with the newly developed system was maintained over time (98% - first, 90.5% - seventh, 93.8% - 15th injection). The thinner, pre-attached 30-gauge needle and the visual signalling of injection completion were among the changes considered as strong improvements to the new system by up to 80.3% of patients.

LIMITATION

Retrospective analysis of current system.

CONCLUSIONS

This survey documented patient satisfaction with different application systems of IFNbeta-1b. The increased satisfaction with the new application system indicates an improvement to the currently used injection system, which may contribute to further advancement in adherence and consequently higher clinical efficacy of treatment.

Different acute tolerance development to EEG, psychomotor performance and subjective assessment effects after two intermittent oral doses of alprazolam in healthy volunteers

BACKGROUND/AIMS

Benzodiazepines (BZDs) are the most effective of the psychotropic drugs in the treatment of anxiety disorders. Tolerance has been reported for the majority of BZDs after chronic administration. However, little attention has been paid to the possibility that tolerance might be present after the intermittent oral administration of BZDs. The objectives of the present study were to assess tolerance development after the administration of two intermittent single oral doses of alprazolam given 15 days apart in healthy volunteers, and to compare the results obtained using measures from different domains: neurophysiological, psychomotor and subjective.

METHODS

Twenty-four healthy volunteers received 2 mg of alprazolam orally on two experimental days, 15 days apart. Plasma concentrations and pharmacodynamics (PD) were assessed before drug intake and at different times in the following 24 h. PD was assessed through EEG (relative alpha and relative beta-1 activities), cancellation task (total and correct number of responses) and visual analogue scales (activity and drowsiness).

RESULTS

No differences were observed in the PKs of alprazolam between occasions. A proteresis was present in both administrations for impairments of psychomotor performance and relative beta-1 activity, whereas it was present only after the second administration for subjective assessments and relative alpha activity. The proteresis on the second occasion was higher than on the first one.

CONCLUSIONS

The administration of two single oral doses of alprazolam, 2 weeks apart in healthy volunteers, yielded the same PKs on both occasions, but significant changes were observed in the PD profile. Acute tolerance was observed after the second administration. Two patterns of acute tolerance development were obtained: (1) impairments of psychomotor performance and relative beta-1 activity, and (2) subjective assessments and relative alpha activity.

Differential effects of alprazolam on the baseline and fear-potentiated startle reflex in humans: a dose-response study

RATIONALE

The "fear-potentiated startle" paradigm has been extensively used in animal studies, and more recently in human experimental psychopharmacology to evaluate the effects of anxiogenic and anxiety-relieving drugs. Previous human studies have shown that both the baseline and the fear-potentiated responses can be inhibited by anxiety-relieving drugs, suggesting drug activity on two different emotional states, the former reflecting a resting condition and the latter more akin to pathological anxiety.

OBJECTIVES

To examine to which extent the reductions induced by a benzodiazepine on the basic and the fear-potentiated startle responses are of equal intensity, and whether or not the drug shows a predominant, i.e., selective, effect on either.

METHODS

The effects of three increasing doses of the benzodiazepine alprazolam (0.25, 0.5, and 1.0 mg) were assessed on the human baseline and fear-potentiated startle responses. Twelve healthy volunteers attended the laboratory on four experimental days and received either alprazolam or placebo according to a double-blind crossover balanced design. Startle recordings were undertaken 2 h after drug intake. Fear potentiation was implemented by means of an electric-shock-anticipation experimental procedure. Additionally, subjective self-reports of sedation and anxiety and psychomotor performance were obtained at 2 and 3 h, respectively, after drug administration.

RESULTS

Alprazolam dose-dependently impaired psychomotor performance and produced increases in subjective anxiolytic activity and sedation, although the latter did not reach statistical significance. Additionally, the drug reduced the magnitude of the startle response both in the absence and in the presence of a threat-related cue, although a differentially greater inhibitory effect was seen on the fear-potentiated response as the dose increased.

CONCLUSIONS

Alprazolam showed a greater inhibitory effect on the fear-potentiated startle than on the baseline reflex, suggesting a more selective action of the drug on those structures mediating potentiation of the behavioral response by anxiety.

Subjective effects and tolerability of the South American psychoactive beverage Ayahuasca in healthy volunteers

RATIONALE

Ayahuasca is a South American psychoactive beverage that contains the naturally occurring psychedelic agent N,N-dimethyltryptamine (DMT). This "tea" has been used for centuries in religious and medicinal contexts in the rain forest areas of South America and is presently gaining the attention of psychedelic users in North America and Europe.

OBJECTIVES

In the present study, the psychological effects and tolerability of ayvahuasca were assessed.

METHODS

Three increasing doses of encapsulated freeze-dried ayahuasca (0.5, 0.75, and 1.0 mg DMT/kg body weight) were administered to six healthy male volunteers with prior experience in the use of this tea, in a single-blind crossover placebo-controlled clinical trial.

RESULTS

Ayahuasca produced significant dose-dependent increases in five of the six subscales of the Hallucinogen Rating Scale, in the LSD, MBG, and A scales of the Addiction Research Center Inventory, and in the "liking", "good effects" and "high" visual analogue scales. Psychological effects were first noted after 30-60 min, peaked between 60-120 min, and were resolved by 240 min. The tea was well tolerated from a cardiovascular point of view, with a trend toward increase for systolic blood pressure. Modified physical sensations and nausea were the most frequently reported somatic-dysphoric effects. The overall experience was regarded as pleasant and satisfactory by five of the six volunteers, while one volunteer experienced an intensely dysphoric reaction with transient disorientation and anxiety at the medium dose and voluntarily withdrew from the study.

CONCLUSIONS

Ayahuasca can be described as inducing changes in the perceptual, affective, cognitive, and somatic spheres, with a combination of stimulatory and visual psychoactive effects of longer duration and milder intensity than those previously reported for intravenously administered DMT.

The role of phytic acid in legumes: antinutrient or beneficial function?

This review describes the present state of knowledge about phytic acid (phytate), which is often present in legume seeds. The antinutritional effects of phytic acid primarily relate to the strong chelating associated with its six reactive phosphate groups. Its ability to complex with proteins and particularly with minerals has been a subject of investigation from chemical and nutritional viewpoints. The hydrolysis of phytate into inositol and phosphates or phosphoric acid occurs as a result of phytase or nonenzymatic cleavage. Enzymes capable of hydrolysing phytates are widely distributed in micro-organisms, plants and animals. Phytases act in a stepwise manner to catalyse the hydrolysis of phytic acid. To reduce or eliminate the chelating ability of phytate, dephosphorylation of hexa- and penta-phosphate forms is essential since a high degree of phosphorylation is necessary to bind minerals. There are several methods of decreasing the inhibitory effect of phytic acid on mineral absorption (cooking, germination, fermentation, soaking, autolysis). Nevertheless, inositol hexaphosphate is receiving increased attention owing to its role in cancer prevention and/or therapy and its hypocholesterolaemic effect.

Extra-virgin olive oil increases the resistance of LDL to oxidation more than refined olive oil in free-living men with peripheral vascular disease

Patients with peripheral vascular disease (Fontaine stage II) are characterized by ischemia of the lower extremities, atherosclerosis and alteration of blood coagulation and fibrinolysis. A randomized, two-period, crossover design was used to compare the effects of extra-virgin (VO) and refined olive (RO) oils on plasma lipids and lipoprotein composition and LDL oxidation susceptibility in free-living men with peripheral vascular disease. The oils differed in their antioxidant profile (alpha-tocopherol: 300 vs. 200 mg/kg; phenolic compounds 800 vs. 60) and concentration but not in their fatty acid composition. Subjects were randomly assigned to two groups. The first group (n = 12) received VO with which to freely cook all meals for 3 mo, followed by a 3-mo wash-out period; they then received RO for the final 3 mo. The second group (n = 12) consumed the oils in the opposite order. Energy, fat, polyunsaturated fatty acids (PUFA) and alpha-tocopherol intakes were not different when patients consumed the two oils. Profiles of the major fatty acids in plasma and LDL were not different after consumption of VO and RO. The slope of the line for LDL oxidation vs. the line for copper concentration was significantly higher after the intake of RO than after the intake of VO. Total LDL taken up by macrophages was significantly greater when the men consumed RO rather than VO. We suggest that antioxidants present in VO may protect LDL against oxidation more than does RO in men with peripheral vascular disease.

Lifestyle changes in free-living patients with peripheral vascular disease (Fontaine stage II) related to plasma and LDL lipid composition: a 15 month follow-up study

Peripheral vascular disease (PVD) is characterized by arteriosclerosis and lower extremity ischemia which cause intermittent claudication. Patients grouped in the Fontaine stage II have more than 75% organic stenosis in their large coronary arteries and exhibit a number of alterations in blood coagulation and plasma lipids. The aim of this study was to evaluate an intervention program of lifestyle habits including dietary recommendations, moderate exercise and decreased smoking in a population of patients with PVD for a period of 15 months, with respect to plasma-lipid and lipoprotein composition as well as LDL susceptibility to peroxidation. These parameters are well known risk indicators of arteriosclerosis and coronary heart disease. A total 13 subjects diagnosed with PVD (Fontaine stage II) were selected, while a healthy age-matched group (n=20) was used as a reference. This study design was an uncontrolled trial of lifestyle interventions. The group of patients was examined at 0, 3, 6, 9, 12 and 15 months. Patients smoking one or more packets of cigarettes per day at the beginning of the study (54.2%) decreased smoking by as much as 7.7% 15 months later. In addition, physical activity intensified significantly (walking > 1 km: 13.1-77%) and treadmill running increased over the study period while the energy intake decreased by 10%. The percentage of saturated fat in the diet decreased by 10% while the intake of polyunsaturated fat rose, and monounsaturated-fat intake showed a parallel trend to increase; the average intake of cholesterol also fell by 10% and plasma triglycerides and HDL-cholesterol showed a trend to decrease and increase, respectively. No permanent changes in LDL lipid fractions for patients were detected during the follow-up period and no differences between patients and the age-matched reference group were found. The macrophage uptake of plasma-oxidized LDL was significantly higher in patients than in the reference group and no differences due to the intervention period were detected. In conclusion, the education in lifestyle and nutritional habits of patients with PVD led to reduced energy intake parallel with augmented physical activity as well to a fall in plasma triglycerides and a rise in HDL-cholesterol, which are good indicators of a reduced risk of vascular and myocardial complications.

Effect of processing methods on the calcium, phosphorus, and phytic acid contents and nutritive utilization of chickpea (Cicer arietinum L.)

The effect of chickpea (Cicer arietinum L.) processing methods on the nutritive utilization of calcium and phosphorus and on phytic acid, a seed component that affects mineral utilization, was studied. Chemical and biological methods were used for nutritional determinations in growing rats. The digestive utilization of calcium from raw chickpea was adequate for growing rats; however, processing resulted in a slight decrease. The metabolic utilization of chickpea calcium was low because of the low rates of net absorption. This was reflected in the decreased calcium levels in longissimus dorsi muscle in the absence of mobilization of calcium from the femur. Soaking in acid solution followed by cooking decreased phytic acid content, suggesting that processing made part of the phytic acid phosphorus available. The absorbed phosphorus was greater than the nonphytic phosphorus supplied by the diet. The digestive utilization of phosphorus was similar in processed and raw chickpeas, despite the loss of soluble anion as a result of processing. These results may indicate the contribution of phosphorus in the form of inositol hexaphosphate-phosphorus.

Augmentation of vincristine cytotoxicity by megestrol acetate

PURPOSE

To determine the effect of a semisynthetic progesterone, megestrol acetate (MA), on the cytotoxicity of various chemotherapeutic agents including vincristine, doxorubicin, actinomycin-D, taxol, vinblastine and colchicine in cell lines with or without P-gp expression.

METHODS

Three cell lines with high P-gp expression (two colon cancer and one leukemia), and a control cell line with no P-gp expression were exposed to chemotherapeutic agents in the presence or absence of MA and drug sensitivity was determined using the MTT colorimetric assay. P-gp-170 expression was detected by flow cytometry using JSB-1 monoclonal antibody and the functionality of MDR expression was tested by rhodamine-123 uptake studies. In vitro drug accumulation studies were performed using [3H]-vincristine. The results were subjected to paired t-test analysis and 95% confidence intervals were determined in cytotoxicity tests.

RESULTS

MA augmented the cytotoxicity of vincristine, but not doxorubicin, actinomycin-D, taxol, vinblastine or colchicine in the three P-gp-expressing cell lines, whereas verapamil augmented the cytotoxicity of doxorubicin and vincristine. MA did not augment the cytotoxicity of vincristine in the P-gp-negative HUT-102 cell line.

CONCLUSION

MA augmented vincristine cytotoxicity in P-gp-expressing cell lines. However, this phenomenon did not occur with the other classic MDR drugs. Therefore, the augmentation of vincristine cytotoxicity by MA can be explained either by involvement of a different mechanism that coexists with the mdr-1 phenotype or by the presence of a different affinity or binding site on the P-gp molecule for MA compared to that for the other classic MDR drugs and verapamil.

Dual chamber pacing in the treatment of congestive heart failure

The present work reviews current literature and the authors' experience of dual chamber pacing in the treatment of patients with congestive heart failure (CHF). In these patients, the atrial contribution to ventricular filling may be less than optimal, especially in the presence of first degree atrioventricular block or mitral insufficiency, both of which are common in the elderly subject with CHF. Dual chamber pacing with short atrioventricular delays has proved effective in enhancing ventricular filling and, in selected cases, cardiac output, with improvement in clinical and instrumental parameters of heart failure. However, for an appropriate atrioventricular synchronization of the left chambers during pacing, the interatrial conduction time must be considered, to avoid atrial contraction against a closed mitral valve. Thus, dual chamber pacing may be a treatment option for CHF that fails to respond to medical therapy.

Influence of dietary supplementation with fish on plasma fatty acid composition in coronary heart disease patients

The effects of dietary supplementation with fish on plasma fatty acid levels were studied in 20 coronary heart disease patients who had suffered acute myocardial infarction. The study was divided into three periods: hospital admission, after 8 weeks on a heart-healthy diet designed for patients with ischemic heart disease, and after 4 weeks on an n-3 fatty acid-supplemented diet in which red meat was replaced with lean and fatty fish. At the end of each period, the subjects responded to a 48-hour recall questionnaire, so that we could assess their compliance with the diet, and blood samples were collected for the determination of plasma fatty acids. Stearic fatty acid was significantly decreased after the fish diet. n-7 and n-9 fatty acids showed no significant changes throughout the study. At the end of the 4-week period when the fish diet was consumed, linoleic acid and its long-chain derivative docosapentaenoic acid (22:5 n-6) were significantly increased. The most notable changes in n-3 series fatty acids at the end of the third period were the significant decrease in linolenic acid and the significant increase in its long-chain derivatives eicosapentaenoic (20:5 n-3) and docosahexaneoic acid (22:6 n-3). These changes in plasma fatty acid levels may have beneficial effects on coronary heart disease.

Influence of hydrocortisone acetate administered to the lactating rat on protein and lactose content in milk and serum protein, glucose and insulin levels in dams and pups

The influence of i.m. administration to the mother of hydrocortisone acetate (doses of 0.4, 0.8 or 2.0 mg/100 g body weight/day) during the first 15 days of lactation on milk protein and lactose composition and serum levels of protein, glucose and insulin in dams and pups is studied. Total serum proteins and albumin/globulin ratio in dams were unchanged by treatment. The daily injection of 0.4 or 0.8 mg/100 g body weight failed to alter serum levels of glucose or insulin in dams, whereas a dose of 2.0 mg/100 g body weight led to a rise in glucemia (from 118 +/- 3.2 to 133 +/- 5.3) which was accompanied by a sharp change in insulinemia (from 40.7 +/- 4.1 to 83.6 +/- 6.9). All three doses raised protein levels in milk. The smallest increase was recorded with 2.0 mg/100 g body weight; this dose also reduced milk lactose content. Total serum proteins in pups rose slightly but nonsignificantly, and no significant effects were noted on albumin/globulin ratio or serum glucose and insulin levels.

Recovery study in Mg-deficient rats given an organic source of Mg

Recovery from Mg deficiency was studied in rats given an organic source of Mg derived from yeast (Saccharomyces cerevisiae) cultured in an Mg gluconate-enriched medium, as the only source of Mg. Magnesium was given either at a rate above the RDA or as a supplement to the regular laboratory diet at the rate of 70 mg Mg/100 g food, of which 40 mg Mg was in the form of MgCO3 and the remaining 30 mg Mg was in the form of the organic product under study. The results showed a good degree of digestive and metabolic utilization of the organic compound, which led to the recovery of normal Mg levels in blood and bone by the end of the 1st week of treatment, and in muscle by the 3rd week of treatment. Muscle Mg content appears to be a good indicator of deficiency. Supplementation above the RDA failed to improve recovery rates in deficient animals.

Influence of hydrocortisone acetate administered to the lactating rat on lipid composition of the milk and serum lipid levels in dams and pups

The influence of i.m. administration of hydrocortisone acetate to the mother (doses of 0.4, 0.8 or 2 mg/100 g body weight/day) during the first 15 days of lactation on milk composition in fatty acids mother and pups serum levels of lipids and their effect on pups' growth is studied. Serum levels of cholesterol and triglycerides in mothers increase at any of the experimental doses. Daily injections of 2 mg/100 g bw to the mother cause an increase in the percentage of C16 as well as in the level of fatty acids derived from linoleic and linolenic acids while reducing the percentage of C18:1. The treatment brings about a higher level in total lipids in the milk which is proportional to the dose. Doses of 0.4 and 0.8 mg increase the percentage of C8 and C10, while the dose of 2 mg enhances the % of C16. A fall in the uptake of linoleic acid by the mammary gland is observed when using any of the experimental doses. No change is observed either in the weight of pups or in serum cholesterol levels while triglyceride level is increased by the effect of treatment. The higher dose increases the level of linolenic acid and some of its derivates.

Nutritional availability of magnesium and calcium in magnesium-supplemented diets

The nutritive utilization of magnesium and calcium was studied using two different formulations of Mg: MgCO3 and an organic dietary Mg preparation. The influence of supplementation with the latter was also studied. The dietary organic magnesium did not modify food intake, which remained adequate in all animals used in the present experiments. Magnesium in both inorganic compound and organic preparation form was well absorbed; furthermore, absorption levels of the latter remained quite stable throughout the different experimental periods. Mg balance in both muscle and femur was similar in all groups studied. Digestive utilization of Ca and Ca content in the longissimus dorsi were higher in animals fed the organic Mg preparation while Ca levels in blood and femur were not affected.

Nutritive utilization of Ca and Mg in Mg-deficient rats: a recovery study

Recovery from Mg deficiency was studied in adult Wistar rats fed a semisynthetic diet containing 0.04% Mg in the form of magnesium carbonate. Daily administration of a diet containing recommended levels of calcium carbonate to Mg-deficient rats led to the recovery, within the first seven days of treatment, of normal values in most of the parameters studied: gain in weight/day, and Mg retention and content in the Longissimus dorsi muscle and femur. Mg levels in whole blood, however, did not fully recovery until the second week of treatment. Net Ca absorption (ADC) and balance were significantly higher in Mg-deficient rats than in controls and remained elevated although to a lesser extent in the femur. Longissimus dorsi muscle, blood and plasma were unchanged by Mg deficiency.

Influence of hydrocortison acetate on the evolution of the nutritive utilization of calcium and phosphorus and their contents on the longissimus dorsi muscle during gestation in the rat

The evolution of the nutritive utilization and plasma and muscular content of calcium and phosphorus in rats is studied, as well as the influence that hydrocortisone acetate has (4 mg/100 g weight and day), on them. In pregnant rats injected with saline solution, the retention of calcium is higher on the days 15-18 as a consequence of the increase on the net absorption of the cation. The balance of phosphorus reaches its maximum hight on days 18-21 of gestation, due to the decrease of the urinary excretion during these days. The administration of hydrocortisone acetate to pregnant rats originate a decrease of the net absorption and an increase of the urinary excretion of calcium and phosphorus, which leads to significantly lower balances than those of animals injected with saline solution. The hormone maintains the animals in a negative balance of phosphorus until day 18 of gestation. Besides, it impedes the high retention of calcium which is found with the control pregnant rats on days 15-18. In general, the content in calcium and phosphorus by gram of dry matter of Longissimus dorsi muscle is not modified during gestation. From day 9 of the treatment with hydrocortisone acetate a significant decrease of calcium and phosphorus of the muscle is observed, that in calcium is the more marked the more the treatment is prolonged. This effect seems to be due to the catabolic action of the hormone.

Influence of hydrocortisone acetate of the longissimus dorsi muscle during gestation of rats

The evolution in detail of the N retention during gestation was studied, dividing it in short periods of time, and how that retention affects Longissimus dorsi muscle. Simultaneously, the same study in pregnant rats treated with hydrocortisone acetate was done. During gestation N balance maintains high values that tend to increase at days 18 to 21. The greatest metabolic utilization of the N dietary corresponds to this period in which the percentage of the N retained in relation to the N absorbed is markedly higher than in previous days of gestation. In spite of the excellent quality and adequate concentration of protein in the diet, the administration of 4 mg/100 g weight and day of hydrocortisone acetate maintains the pregnant rat in a negative balance until day 18, as a consequence of the decrease in food intake and faecal and urinary N losses. From day 18 to day 21 of gestation the balance of N increases and the metabolic utilization of the dietary N is similar between pregnant rats injected with NaCl 0.9% and pregnant rats injected with hydrocortisone acetate. The Longissimus dorsi normal growth pattern (in relation to weight and N content) in young adult rats is not modified by gestation. The catabolic effects of hydrocortisone acetate on Longissimus dorsi muscle in pregnant rats can be observed from day 9 of treatment. The longer the treatment the higher the effect is.

Influence of hydrocortisone acetate on the magnesium metabolism during pregnancy in rats

The influence of hydrocortisone acetate i.m. administered (4 mg/100 g of body weight and day) to pregnant rats, on magnesium nutritive utilization and bone magnesium content in the mothers and its possible repercussions on newborn Mg content are studied. Hydrocortisone acetate treatment significantly reduces Mg content in the litters, which can be explained on the basis of a significant decrease in both the magnesium absorption and retention by the hormone-treated mothers. The mobilization of femoral magnesium and the increase in the urinary excretion of the cation provoke a reduction in magnesium retention in the treated mothers.

Magnesium utilization during gestation in the rat and effect of hydrocortisone on it

The changes of magnesium utilization during pregnancy in rat and the influence of hydrocortisone acetate on it was studied. In the late days of gestation the Mg balance and magnesium content of bone increased significantly. This may be due to a greater requirement at this stage and to bone acting as a store for this cation. Hydrocortisone acetate at a dose of 4 mg/100 g body weight/day decreased the magnesium balance but did not modify the bone content of this mineral. The hormone had a catabolic effect on Longissimus dorsi muscle, producing a loss in magnesium. The effect is directly proportional to the duration of treatment.

Influence of gestation and hydrocortisone-acetate treatment on the nutritive utilization of protein

The effect of pregnancy and of cortisol on the digestive and metabolic utilization of protein in Wistar rats was studied. The cortisol is i.m. administered during 21 days in a pharmacological dose (4 mg/100 g weight per day) to female Wistar rats. Pregnancy is observed to increase and cortisol to decrease significantly the food intake (g dry matter/rat per day); the intake of nitrogen follows the same pattern. Pregnancy significantly increases the weight of both groups: pregnant rats as comparison to non-pregnant rats saline injected and pregnant rats cortisol-treated in relation to the animals pregnant but not hormone-treated. The increase being greater in the last 5 days of pregnancy. Cortisol in the pregnant and non pregnant rats considerably reduces the weight. The protein absorption is unaltered by pregnancy but is diminished by the effect of cortisol. Pregnancy increases the balance of nitrogen in both sets of rats; the increase being significantly greater in the last period of pregnancy. When administered to non pregnant rats, cortisol produces a negative balance of nitrogen. The protein of good quality (casein + 5% DL-methionine at a level of 12%) partially equalizes the negative effect of cortisol in spite of the long treatment and high doses used.

Proteic-anabolic capacity in rats--influence of the quality and quantity of dietary protein

The effect of quality (casein + 5% DL-methionine, normal or heated at 180 degrees C for 20 min) and quantity (4%, 6%, 10%, 15% and 20%) of dietary protein on food intake, weight increase and nitrogen retention, has been studied in both sexes weaning Nestle rats. Our results show that food intake, when expressed as g dry matter/100 g body weight and day, is not dependent on the quality and quantity of dietary protein. Weight increase goes up at a 10% dietary protein level. At higher protein levels (15% and 20%) values are only maintained. Protein quality do not cause any difference. Nitrogen retention goes up on increasing dietary protein level, with a maximum at 10% casein-methionine and 15% heated protein, being retention heated casein-methionine significantly lower. At a higher protein level, the maximal anabolic capacity for protein is maintained. Maximum Protein Productive Value (PPV) is obtained from diets containing 10% protein level (normal or heated). There is a significant decrease at higher protein levels (15% and 20%). The PPV of heated casein-methionine is lower than PPV of normal one at 6%, 10%, 15% and 20% protein levels. The results state that in our assays, in spite of the good quality of heated casein-methionine, its metabolic efficiency is below non heated protein values even when protein contribution is increased. We can assume that protein quantity is not a balancing factor for protein quality.

Effect of cortisol on some nutritional and biochemical parameters in pregnant rats and their foetuses

The influence of hydrocortisone acetate treatment (4 mg/100 g body weight i.m. and daily injected) was studied in pregnant rats and their litters. The parameters controlled were: food intake, body weight and body nitrogen, and liver enzimatic activity of PEPCK, in the mothers and number of foetus, weight, body nitrogen content and liver PEPCK activity in the litter. The hormonal treatment induces a significant reduction of food intake and weight of the mothers. In the same way the total body nitrogen content, is reduced but not its concentration (body nitrogen content/g body weight). Likewise, cortisone injection reduces the number of newborns, and, significantly, the individual weight of the same. At the 21st gestation day, the nitrogen content of the litter, given by g of weight, is also significantly reduced. Liver activity of PEPCK was significantly increased in the pregnant rat in all days under study and was not detected in the foetus in the 21st day.

[Effect of the dietary protein level and hydrocortisone acetate treatment to pregnant rats on the newborns]

The influence of dietary protein level (three diets provided with 4% (D1), 12% (D2) and 14% (D3) of protein were tested) and hydrocortisone acetate administration (4 mg/100 g body wt. were daily injected), to rats during pregnancy, were studied. The parameters considered were the number, weight and nitrogen content of the litter. The D3 diet caused a significant increase in the newborns number, whether the mothers were hormone-treated or not. Cortisol associated to the D1 diet led to an appreciable fall in this parameter. Total N content of the litter, which had revealed independent of the dietary protein level in the control groups (rats without hormonal treatment), decreased significantly after cortisol administration in both the three experimental groups. This latter effect was more intense in litters coming from rats fed on the D1 diet. When the N content is expressed as mg N/g litter weight, this parameter decreased significantly only when the cortisol treatment was associated to the D1 diet.

[Intestinal resections in rat: influence on protein absorption (author's transl)]

The effect of resections of 50% and 80% of small intestine, starting from the ileocecal valve on the nutritive utilization of protein, has been studied in rats. As a result of the resections, in the second week after the operation, the intake and weight of the animals decreased in both kinds of resections. The biggest decrease occurred in rats with 80% resection, while the loss of nitrogen in the faeces was greatly increased and, as a result, the digestibility coefficient was significantly reduced. The resected animals tended to recover gradually, but it was hardly noticeable at six and nine weeks after the operation. However, after three months, the recovery, although not total, was quite obvious, and the recovery rate was greater in the rats with 50% than in those with 80% resection.