Glycogen synthase kinetics in isolated human adipocytes: an in vitro model for the effects of insulin on glycogen synthase

Glycogen synthase which catalyzes the incorporation of uridine dipophosphate glucose into glycogen is found in muscle, liver, and fat. The activity of this enzyme is increased by insulin through a dephosphorylation mechanism. Because of the critical role of glycogen synthase in glucose storage and overall glucose metabolism, it is important to assess the status of the activity of this enzyme in normal humans as well as in individuals with pathological conditions, such as non-insulin-dependent diabetes mellitus. However, in human subjects, studies of the regulation of glycogen synthase in vivo are time consuming and tedious. The present study was, therefore, undertaken to establish whether adipocytes isolated from subcutaneous adipose tissue biopsies from normal human subjects could be used to assess the effect of insulin in vitro on glycogen synthase activity. Regulation of glycogen synthase in human adipocytes by glucose 6-phosphate and uridine disphosphate glucose was found to be somewhat different than that reported for the regulation of this enzyme in tissues from other species. The adipocyte was found to be a sensitive model for insulin activation of this enzyme. Glycogen synthase was stimulated twofold by an insulin concentration of as low as 1 ng/ml, while half-maximal activation of enzyme activity occurred at 0.4 +/- 0.1 ng insulin/ml. The present studies indicate that the isolated human subcutaneous adipocyte may serve as a useful model for in vitro investigation of the effects of insulin on glycogen synthase.

Impaired morphological development of the dorsal cochlear nucleus in hamsters treated postnatally with alpha-difluoromethylornithine

The dorsal cochlear nucleus is a highly organized nucleus in the auditory system in which the ramifications of depletion of specific cell types during development can be studied. Granule cells, small interneurons that are located in all layers of the DCN in the adult hamster, proliferate postnatally and are, therefore, potentially vulnerable to anti-mitotic agents that are administered after birth. The present experiments describe the effects of alpha-difluoromethylornithine, a drug that inhibits proliferation of cerebellar granule cells, on the granule cells in the dorsal cochlear nucleus. As in the cerebellum, the density of granule cells in the dorsal cochlear nucleus is reduced after alpha-difluoromethylornithine treatment. In hamsters treated with alpha-difluoromethylornithine (200 or 500 mg/kg subcutaneously (s.c.), twice daily on postnatal days 4-14), the numerical density of granule cells was reduced in the superficial dorsal cochlear nucleus at 15 days; by 40 days this effect was also apparent in the deep layer, suggesting that cells located superficially that would have migrated into the deep dorsal cochlear nucleus had either failed to develop or did not arrive at their final location. This evidence suggests that the cells normally migrate down from the superficial proliferative zone into the deeper layers. In the drug-treated animals, a layer of mixed granule cells and fusiform cells was thinner than in controls probably due to the reduction in interspersed granule cells since the number of fusiform cells was unaffected. There was also a dose-dependent effect on cell growth; fusiform cells were affected at both doses, while giant cells were only affected at the highest dose. Granule cells form a major input to the fusiform cells and their depletion may account for some of the effects on fusiform cell growth. There could also be additional direct actions of alpha-difluoromethylornithine on this population.

Biochemical determinants of growth sparing during neonatal nutritional deprivation or enhancement: ornithine decarboxylase, polyamines, and macromolecules in brain regions and heart

In order to elucidate the biochemical mechanisms operating to protect the brain from growth retardation in response to nutritional deprivation, comparisons were made of markers of cellular development in brain regions (cerebellum, cerebral cortex, midbrain + brainstem) and in a tissue which is not spared (heart). Nutritional status of neonatal rats was manipulated by increasing or decreasing the litter size beginning at birth, and development of DNA, RNA, and proteins followed throughout the neonatal period. In addition, we assessed the activity and levels of ornithine decarboxylase and its metabolic products, the polyamines, which are known to coordinate macromolecule synthesis in immature tissue and to provide an early index of perturbed development. Cardiac ornithine decarboxylase and polyamines were altered within 48 h of initiating the changes in litter size, and the direction and magnitude of these biochemical effects were predictive of subsequent impairment or enhancement of organ growth and of cellular development. All three brain regions were buffered from growth alterations relative to the heart, but the cerebellum, which undergoes major phases of cell replication later than the other two regions, was somewhat less protected. The spared brain regions also showed evidence of compensatory hypertrophy in nutritional deprivation (increased protein/DNA ratio) which accounts for maintenance of growth in the presence of reduced cell numbers. Thus, brain growth sparing involves specific cellular responses which are dependent on the maturational profile of each brain region.

Regional cerebral palmitate incorporation following transient bilateral carotid occlusion in awake gerbils

[14C]Palmitate was injected intravenously in awake gerbils at various times after 5 minutes of bilateral carotid artery occlusion or a sham operation. Regional rates of incorporation of plasma palmitate into the hippocampus and other regions of the anterior circulation were determined relative to the mean rate of incorporation into regions of the posterior circulation using quantitative autoradiography and a ratio method of analysis. One day after bilateral carotid occlusion, relative palmitate incorporation was elevated significantly by 16% in the CA4 pyramidal cell layer and by 20% in the dentate gyrus of the hippocampus compared with sham-operated gerbils. At 3 days, significant elevations of this magnitude were found in the CA3 and CA4 cell layers, whereas relative incorporation was reduced by 26% in the CA1 pyramidal cell layer. At 7 days, the only significant difference from control was a 15% elevated incorporation in the CA3 pyramidal cell layer. Histologic examination indicated substantial cell death in the CA1 pyramidal layer at 3 days, with extensive glial reaction and phagocytic invasion at 7 days. Our results suggest that the turnover of palmitate-containing lipids is reduced in the CA1 layer of the gerbil hippocampus but that lipid synthesis is stimulated in hippocampal regions (CA3, CA4, dentate gyrus) affected by but recovering from transient bilateral carotid occlusion.

Effects of insulin infusion on human skeletal muscle pyruvate dehydrogenase, phosphofructokinase, and glycogen synthase. Evidence for their role in oxidative and nonoxidative glucose metabolism

To determine whether activation by insulin of glycogen synthase (GS), phosphofructokinase (PFK), or pyruvate dehydrogenase (PDH) in skeletal muscle regulates intracellular glucose metabolism, subjects were studied basally and during euglycemic insulin infusions of 12, 30, and 240 mU/m2 X min. Glucose disposal, oxidative and nonoxidative glucose metabolism were determined. GS, PFK, and PDH were assayed in skeletal muscle under each condition. Glucose disposal rates were 2.37 +/- 0.11, 3.15 +/- 0.19, 6.71 +/- 0.44, and 11.7 +/- 1.73 mg/kg X min; glucose oxidation rates were 1.96 +/- 0.18, 2.81 +/- 0.28, 4.43 +/- 0.32, and 5.22 +/- 0.52. Nonoxidative glucose metabolism was 0.39 +/- 0.13, 0.34 +/- 0.26, 2.28 +/- 0.40, and 6.52 +/- 1.21 mg/kg X min. Both the proportion of active GS and the proportion of active PDH were increased by hyperinsulinemia. PFK activity was unaffected. Activation of GS was correlated with nonoxidative glucose metabolism, while activation of PDH was correlated with glucose oxidation. Sensitivity to insulin of GS was similar to that of nonoxidative glucose metabolism, while the sensitivity to insulin of PDH was similar to that of glucose oxidation. Therefore, the activation of these enzymes in muscle may regulate nonoxidative and oxidative glucose metabolism.

Critical development periods for inhibition of ornithine decarboxylase by alpha-difluoromethylornithine: effects on ontogeny of sensorimotor behavior

The roles of ornithine decarboxylase and the polyamines in behavioral development were examined through the use of alpha-difluoromethylornithine, a specific irreversible inhibitor of ornithine decarboxylase. alpha-Difluoromethylornithine was administered either prenatally during gestation (days 15-17) or postnatally (days 1-20) to examine critical periods of sensitivity. Prenatal alpha-difluoromethylornithine administration resulted in a deficit in early sensorimotor ontogeny: latencies in surface righting reflex (postnatal days 1-5) and negative geotaxis (postnatal days 5-8) were prolonged, and time spent pivoting (postnatal days 7, 9, and 11) was reduced. In contrast, postnatal alpha-difluoromethylornithine primarily influenced later maturing, complex integrative behaviors such as swimming and open field activity. Thus, the behavioral effects of alpha-difluoromethylornithine exposure are highly dependent upon the age at which the drug is administered, a finding in keeping with the participation of the ornithine decarboxylase/polyamine system in cell replication and differentiation during discrete periods of neural development. The behavioral consequences of ornithine decarboxylase inhibition during these critical periods are thus related primarily both to the timetable for cellular maturation in each brain region.

Adipocyte glycogen synthase and pyruvate dehydrogenase in obese and type II diabetic subjects

To determine whether 1) insulin stimulates pyruvate dehydrogenase (PDH) and glycogen synthase (GS) in isolated human adipocytes and 2) adipocytes from subjects with obesity or noninsulin-dependent diabetes mellitus (NIDDM) are resistant to the effects of insulin, PDH and GS were assayed in adipocytes from 11 control, 8 obese, and 9 NIDDM subjects. Basal PDH activities were 123 +/- 20, 129 +/- 21, and 128 +/- 25 pmol pyruvate oxidized/min per 2 X 10(5) adipocytes in these groups. Insulin stimulated PDH activity to a maximum of 223 +/- 38 pmol/min per 2 X 10(5) in adipocytes from control subjects, but did not significantly increase values from obese subjects. Insulin significantly decreased PDH activity in cells from NIDDM subjects (99 +/- 20 pmol/min per 2 X 10(5) cells, P less than 0.05). PDH activity assayed with high magnesium and calcium concentrations was significantly stimulated by insulin in adipocytes from control, but not obese or NIDDM subjects. GS assayed with 1 mM glucose 6-phosphate did not differ significantly among control, obese, or NIDDM subjects (446 +/- 110, 451 +/- 156, and 291 +/- 35 pmol incorporated into glycogen, respectively). Insulin significantly stimulated glycogen synthase in all three groups (827 +/- 179, 764 +/- 177, and 569 +/- 51 pmol incorporated) to a similar extent. Glycogen synthase assayed with 10 mM glucose 6-phosphate was decreased in NIDDM (1,335 +/- 131 pmol incorporated) compared with obese or control subjects (2,512 +/- 451 and 2,239 +/- 230 pmol incorporated, respectively, P less than 0.01).

Incorporation of plasma palmitate into the brain of the rat during development

Jpalm, the rate of incorporation of plasma palmitate into brain, was determined in awake Fischer-344 rats at 15, 20, 25 and 38 days of age, by a modification of the method of Kimes et al. [14C]palmitate was injected intravenously and plasma-specific activity of unesterified palmitate was followed until the animals were killed at 4 h, when radioactivity was determined by quantitative autoradiography in 45 individual brain regions. Jpalm was calculated as the 4 h brain radioactivity divided by integrated plasma palmitate-specific activity to 4 h. Jpalm rose between 15 and 20 days of age in gray and white matter regions, then declined 4-5-fold in gray matter and 7-10-fold in white matter by 38 days and reached adult levels by 3 months. The white/gray ratio for Jpalm declined significantly between 20 and 38 days, and between 38 days and 3 months of age, consistent with a lower rate of turnover of white matter lipids in the mature brain. The results support the use of the Jpalm technique to measure brain lipid synthesis and turnover. They show that Jpalm corresponds to the time course of myelination during development of the rat brain, when there are parallel changes in the rates of palmitate incorporation into gray and white matter regions.

Perinatal dietary supplementation with a soy lecithin preparation: effects on development of central catecholaminergic neurotransmitter systems

Previous work has shown that exposure of developing rats to soy lecithin preparations (SLP) influences macromolecular constituents of immature brain cells and causes abnormal behavioral patterns. To determine if synaptic mechanisms are adversely affected by SLP, we examined the developmental characteristics of noradrenergic and dopaminergic pathways in discrete brain regions. Although transmitter levels were unaffected, the utilization rates of both catecholamines were profoundly disturbed in an age-dependent, regionally-selective manner. Utilization tended to be subnormal in the preweanling stage, but demonstrated a postweaning elevation in cerebellum and midbrain + brainstem. Enhanced utilization persisted in the latter region only, and cerebral cortex actually showed a lowered utilization rate in adulthood (60 days of age). Transmitter uptake capabilities were also affected by developmental exposure to SLP, as was tyrosine hydroxylase activity. The patterns of effects on these two variables indicated that the altered transmitter utilization rate probably reflected a change in impulse activity in the affected neuron populations, with promotion of activity in the midbrain + brainstem and reduced activity in the cerebral cortex. These data indicate that dietary supplementation with SLP throughout perinatal development alters synaptic characteristics in a manner consistent with disturbances in neural function.

Perinatal dietary exposure to soy lecithin: altered sensitivity to central cholinergic stimulation

The effects of perinatal exposure to soy lecithin preparation (SLP) on the development of cholinergic responses in the rat brain were examined by assessing the ability of intracisternally administered carbachol to stimulate 33Pi incorporation into phospholipids in vivo, an effect of carbachol mediated by muscarinic cholinergic receptors. Maternal intake of SLP produced a suppression of the cholinergic response in the offspring, an effect which was specific in that basal (unstimulated) incorporation rates were not reduced (in fact, they eventually became elevated), nor was the response to another neurotransmitter (dopamine) compromised. The effect occurred early in the preweanling stage, a period in which SLP exposure also enhances development of cholinergic nerve terminals. These results suggest that SLP exposure has a major effect on cholinergic synaptic development and reactivity, followed by secondary changes in other neurotransmitter pathways and by more generalized effects on basal membrane phospholipid turnover.

Perinatal dietary supplementation with a commercial soy lecithin preparation: effects on behavior and brain biochemistry in the developing rat

Rats exposed perinatally to dietary commercial soy lecithin preparation (SLP) showed alterations in sensorimotor development and brain cell maturation. Latencies for righting responses (measured on postnatal Days 1-4) and negative qeotaxis (measured on postnatal Days 5-8) were shorter in the SLP treated animals. This pattern was accompanied by specific alterations in cerebellar development; biochemical markers for cellular maturation indicated a compression of the ontogenetic time course, as assessed by ornithine decarboxylase (ODC) activity, and levels of nucleic acids and proteins. In contrast, cellular development in the cerebral cortex indicated a generalized slowing of the time course of maturation and a deficit in the number of cells which persisted into adulthood. Behavioral abnormalities also did not disappear in adulthood, as morphine analgesia was markedly reduced in the SLP group. These results indicate that exposure of the fetus and neonate to dietary SLP during development leads to regionally specific alterations in brain cell maturation associated with disruption or behavioral patterns.

Effects of a commercial soy lecithin preparation on development of sensorimotor behavior and brain biochemistry in the rat

Pregnant rat dams and offspring were exposed to a 5 or 2% soy lecithin preparation or a control diet. Enrichment was either lifelong beginning at gestation, limited to the time preceding, or the time following weaning, or absent (constituting a "pure" control group). The most marked early sensorimotor deficits (reflex righting and swimming development) were seen in the 5% soy lecithin preparation group, although all soy lecithin preparation-exposed offspring had elevated brain/body weight ratios and choline acetyltransferase levels. Later, animals exposed to lifelong 5 or 2% soy lecithin preparations were hypoactive, had poor postural reflexes, and showed attenuated morphine analgesia. The results indicate that dietary soy lecithin preparation enrichment during development leads to behavioral and neurochemical abnormalities in the exposed offspring.

The swollen leg: ultrasonographic demonstration of non-thrombotic causes

Grey-scale ultrasound is a useful investigation in selected patients with a painful swollen leg. It is of particular value in cases in which there is a clinical suspicion of deep vein thrombosis (DVT) but other features, such as an atypical history or equivocal radiology, suggest alternative pathology. Five such cases are presented in which ultrasound showed transonic lesions. The cause of the swelling of the leg was thus shown to be "cystic' in nature and therefore not due to DVT. This enabled inappropriate and potentially harmful therapy to be avoided and the correct therapy, such as surgical drainage, to be undertaken.

Leaf Gland Flavonoids in Comptonia peregrina and Myrica pensylvanica (Myricaceae)

Natural products are formed in some Myricaceae by secretory glands on leaves, young twigs, and fruits. Leaf glands of Myrica pensylvanica and Comptonia peregrina produce flavonoid aglycones along with terpenoid material. This is the first study on exudate flavonoids of the two species. In M. pensylvanica rare C-methylated flavonones and chalcones, such as cryptostrobin, desmethoxymatteucinol, aurentiacin, and myrigalon-D, are the major constituents. In C. peregrina chrysin, galangin, pinocembrin, and their methyl ethers are dominant. They are accompanied by some of the C-methyl flavonoids found in M. pensylvanica. A novel natural flavanone, 7-hydroxy-5-methoxy-6-C-methyl flavanone (comptonin) was isolated from C. peregrina, where it was encountered along with trace amounts of the corresponding 2',4'-dihydroxy-6'-methoxy-5'-C-methyl chalcone.

A comparison of two high-density barium sulphate preparations for double-contrast barium meals

The mucosal coating properties, liability to bubble formation and palatability of a new barium sulphate suspension (Micropaque HD) were compared with those of the barium suspension shown by previous trials to produce the best results (E-Z-HD). The results show that E-Z-HD gave significantly better mucosal coating and was less liable to bubble formation. There was no significant difference in the palatability of the two preparations.

Nutrients and toxicants in rapeseed meal: a review

The composition of rapeseed meal and hulls is reviewed with emphasis on components of nutritional interest. Carbohydrates in rapeseed meal are mainly pectins, pentosans and cellulose and comprise nearly one-half the gross energy. The digestibility of energy is lower for rapeseed than for soybean meal. Protein is well digested, but the protein digestion coefficient and the availability of amino acids are lower than for soybean meal. Data on digestible and metabolizable energy are summarized. The kinds of glucosinolates present in high (HG) and low (LG) glucosinolate rapeseed meal and the nature of their hydrolytic products are discussed. The toxic effects of oxazolidinethione , isothiocyanates, thiocyanates and nitriles, and their relationship to their parent glucosinolates , to myrosinase action and to conditions during rapeseed processing are reviewed briefly. The effects of glucosinolates in animal tissues and products and the effects of converting to LG rapeseed meal are presented. Finally, a brief review is given of the responses of swine and cattle to the feeding of HG and LG rapeseed meal. The nutritional advantages of LG rapeseed meal, over the older type HG meal, are clearly evident from the feeding trials.

Neurofibrosarcoma in Von Recklinghausen's disease presenting with hypochromic anaemia

A patient with Von Recklinghausen's disease who developed a retroperitoneal neurofibrosarcoma is described. The presenting clinical picture was one of hypochromic anaemia with a large mass palpable in the left hypochondrium. At operation the tumour was found to be invading the small intestine with resultant blood loss. The patient had presented 21 years before with unexplained severe iron deficiency anaemia.

Amino acid requirements of growing mice: arginine, lysine, tryptophan and phenylalanine

Linear programmed diets designed to maximize the use of proteins and to minimize the use of free (1-) amino acids, and containing five dietary levels of each amino acid under test, were fed to weanling crossbred Carworth Farms No. 1 x Swiss mice in 14-day growth trials. Arginine dietary levels were 0.1, 0.2, 0.3, 0.4 and 0.7%; lysine: 0.2, 0.3, 0.4, 0.5 and 1.0%; tryptophan: 0.03, 0.07, 0.10, 0.13 and 0.17%; and phenylalanine: 0.10, 0.25, 0.40, 0.55 and 0.89%. Growth, feed consumption and regression-adjusted growth rates indicated the following minimum requirements: arginine less than 0.1% and probably zero, lysine 0.4%, tryptophan 0.1% and phenylalanine 0.4%. The AIN '76 reference diet was included in each amino acid test and resulted in superior growth and feed utilization. It was postulated that the greater content of free amino acids in our diets may have affected the efficiency of feed utilization adversely.

Influence of weed seed oil contamination on the nutritional quality of diets containing low erucic acid rapeseed (Brassica napus, Tower cultivar) oil when fed to rats

Oils from three samples of rapeseed screenings and a sample of stinkweed seeds (Thlaspi arvense) were added to Tower rapeseed oil at three levels (5, 10 and 15%). The contaminated Tower oils were fed at 20% (w/w) of a purified diet to male weanling Sprague-Dawley rats for 16 weeks. The screenings oils caused no increase in the focal myocardial lesion index or lipidosis of the rat hearts. Stinkweed oil gave a significant increase in myocardial lipidosis and a non-significant increase of the myocarditis index. These were attributed to an imbalance in the fatty acid composition of the Tower oil for the specific requirements of the growing rat. Screenings oil contamination had no significant effects on the feed intake or growth of the animals. The growth of rats fed stinkweed oil-contaminated diets was significantly lower than other treatments when it was adjusted for feed intake by analysis of covariance. No treatment effects on body organ weights nor on blood lipid parameter were observed. The presence of week seed oils, at the highest levels likely to be encountered in low erucic acid rapeseed oil, was concluded to have a significant influence on its nutritional value.

Effects of fetal and early postnatal thiamin deficiency on avoidance learning in rats

Thiamin deficiency was induced in two groups of young rats during two stages of growth: deficiency 1, from 8 days prepartum to 10 days postpartum or deficiency 2, from 1 to 18 days postpartum. The deficiency was reversed by thiamin injections for 5 days and return to a normal diet following which animals were tested at 35 days of age. Body weights at 21 and 36 days of age were not significantly reduced by the deficiency nor was brain weight affected. Activity levels were not significantly reduced by deficiency 1 but were reduced in deficiency 2. Both active and passive avoidance learning were significantly impaired in both deficiency 1 and 2, a finding which could not be attributed to alterations in pain sensitivity, motor ability or reduced activity levels. The results indicate that the developing brain is vulnerable to reduced thiamin intake and that the period of vulnerability may be different for activity and avoidance learning.

Nutritional evaluation of oilseeds and legumes as protein supplements to cereals

Several oilseed and legume protein products were fed to rats as the sole source of dietary protein, and in blends with cereals for the determination of protein efficiency ratio (PER) and biological availability of amino acids. In addition oilseed protein isolates were fed to mice for the determination of PER. Results of the mouse study revealed that the adjusted PER (casein = 100)for Target rapeseed isolate (108) was higher than those of sunflower (74), safflower (77), soybean (86) or flax (92) isolates. Results of the rat trials revealed that the adjusted PER for Twoer rapeseed meal (88) was higher than those of fababean (21), field pea (59) and soybean meal (72). Supplementation with methionine (0.2%) resulted in improved PER for fababean (84), field pea (101) and soybean meal (97). Mustard flour and rapeseed flour gave PER of 109 and 106, respectively, while the value of sunflower flour was low (56). Protein isolates of Tower rapeseed and soybean gave PER of 92 and 80, respectively. Blending of legumes and oilseeds with wheat flour (PER = 28) gave high PER values (60--85), as also occurred in rice blends (71--88). Supplementation of wheat-legume blends with lysine (0.4%), methionine (0.2%) and threonine (0.1%) brought all PER values above 100. It appeared that differences in PER of the diets paralleled the levels of the first limiting amino acid for rat growth. Results of balance trials indicated that the availability of the limiting amino acid(s) was lower than other essential amino acids for each protein source.

Effects of plant and animal lipids rich in docosenoic acids on the myocardium of Cynomolgus monkeys

Cynomolgus monkeys (Macaca fascicularis) were fed diets containing 25% rapeseed oil (RSO), partially-hydrogenated herring oil (PHHO) or a 3:1 mixture of lard/corn oil as control (CON) for 4 months. The RSO contained approximately 25% of the fatty acids as erucic acid (cis-docos-13-enoic, 22:1w9) while the PHHO contained a similar concentration of mainly cetoleic acid (cis-docos-11-enoic, 22:1w11). The CON contained no 22:1 acids. The monkeys developed the expected myocardial lipidosis, somewhat more pronounced in the RSO than the PHHO group, but small foci of mononuclear cell infiltration, while infrequent, occurred in all three groups. Significant intergroup differences in biochemical or hematologic measurements of serum constituents were an increase in serum cholesterol concentration in the RSO group and an increase in serum glutamicoxaloacetic transaminase activity in both RSO and PHHO groups at certain intervals. The shorter proportion of M. fascicularis life span represented by this experiment may account for the absence of clear intergroup differences such as are reported in rats used in similar studies.

Problems in general anaesthesia. Dental

Administration of general anaesthetics in the dentist's surgery is widely practised in Australia. There is considerable demand for this service, and those doctors who supply it fill a very real need. Where medical practitioners fail to supply this service, dentists are forced to use sedation techniques and may be tempted to push these beyond the limits of safety.

Stressful life events and coping methods in mental-illness and -wellness behaviors

A descriptive comparative study examined not only the relationship between stressful life events and mental-illness and -wellness behaviors but also the coping methods used by individuals exhibiting each behavior. Data collection included the use of the Holmes and Rahe Social Readjustment Rating Scale and an 18-item coping scale administered to experimental and control samples. The experimental group consisted of 30 psychiatric inpatients in three general hospitals who were oriented in three spheres. Control group subjects had no history of psychiatric illness, were currently not receiving medical treatment, and were adequately functioning in socially accepted roles. They were randomly selected to match the patient on the basis of age, sex, and county of residence. The experimental group reported that significantly more stressful life events had occurred in the last six months and significantly more short-term than long-term coping methods had been used when compared with the control group. Sex and age differences were noted. A significant association was found between high stress scores and short-term coping methods for subjects in both groups. The concept of change as it relates to stress and its effect on health is an important consideration for health care professionals whose goals are health maintenance and illness prevention.

Amino acid requirements of the growing mouse

Using diets based on rat amino acid requirements, containing 2.0% nitrogen and 4.1 digestible kcal/g, the dietary levels of ten essential amino acids required for normal post-weaning growth of Swiss X Carworth Farms No. 1 crossbred mice were estimated. The response criteria used were growth rate, dry matter intake, energy and protein contents of body weight gain, protein efficiency ratio and apparent biological value. Maximum responses were obtained when the dietary dry matter contained less than or equal 0.3% arginine, 0.2% histidine, 0.4% isoleucine, 0.7% leucine, less than or equal 0.4% lysine, 0.5% methionine, less than or equal 0.4% phenylalanine, 0.4% threonine, less than or equal 0.1% tryptophan and 0.5% valine.

Dental anaesthesia in children

Traditional methods of out-patient general anaesthesia for dentistry in children are critically examined.

A method is described which is acceptable to anaesthetists; the safety of performing this on an out-patient basis is discussed in detail.

RELATIONSHIP BETWEEN IN VITRO DIGESTIBILITY AND FINENESS OF SUBSTRATE GRIND AS AN INDICATOR OF VOLUNTARY INTAKE OF HAY BY SHEEP

Hay of two alfalfa varieties and four grass species harvested at six maturity stages each was fed to sheep. Voluntary intakes were measured in grams of dry matter daily per kg of metabolic size. Samples were ground coarsely and finely and digested in vitro. Fine grinding did not increase the digestibility of immature hay, but with advancing maturity the fine substrate was progressively more digestible than the coarse. This difference was inversely related (P < 0.05) to voluntary feed intake. The regression of voluntary intake of dry matter (g/day/kg0.75 body weight) on the difference of in vitro digestibility of organic matter in finely and coarsely ground substrate was −2.32 g in the alfalfa hay and −4.18 g in the grass hay. The coefficient of variation from regression was 14% in the alfalfa and 17% in the grass hays. Fine grinding had a greater effect on the in vitro digestibility of organic matter than of dry matter. This resulted in a higher significance of the relationship of intake with the effect of grinding on the digestibility of organic matter than on that of dry matter.

NUTRIENT DIGESTIBILITY BY NEW-BORN CALVES FED MILK REPLACER

The digestibilities of nutrients in milk replacer were determined with eight male Holstein-Friesian calves from 6 to 24 days of age. The milk replacer contained dried skim-milk supplemented with mixed animal–vegetable fat, fine oat meal, vitamins and minerals.The digestibilities of all nutrients were low at 6 days of age but improved throughout the experiment. Marked improvement (P < 0.05) occurred from 5 to 14 days of age. The digestibility of fat improved from 29 to 82% between 6 and 24 days of age and showed the greatest overall improvement. A temporary diarrhea characterized by soft feces with no detectable systemic effects was present in each calf for the first week.Over the test period, the digestibility of energy improved from 72 to 88%. The digestibility of "calculated" non-fat, non-protein energy increased from 54 to 77%. Oat meal energy was calculated to be totally indigestible at 6 days and improved to only 26% digestible at 24 days of age, confirming previous work that cereal starch was not well utilized by calves under 24 days of age.The digestibilities of the fatty acids capryllic, capric and lauric were all 90 to 100%; those of palmitoleic, oleic and linoleic were 89, 75 and 79%, and palmitic and stearic acids only 42 and 26% digestible, respectively.The digestibility coefficients of amino acids were generally high, averaging 70 to 86%, with some low values during the first week of life and with methionine averaging 11% digestible. In several periods during the first half of the experiment, methionine showed negative coefficients. Cystine was only moderately well digested.

FURTHER OBSERVATIONS ON LYSINE AND PROTEIN REQUIREMENTS OF 23 TO 89 KILOGRAM PIGS

The results of four related experiments are presented. The first involved three levels of lysine (0.58, 0.68, 0.78%) and cross-treatments of brewers’ yeast and alfalfa meal. The pigs were individually fed linear-programmed rations based on National Research Council standards from 23 to 57 kg. The pigs averaged 0.64 kg gain/day. No response was obtained to lysine beyond 0.58%. Feeding alfalfa resulted in increased feed intakes. In the second trial, the 0.68 and 0.78% lysine levels were obtained by adding lysine to the 0.58% lysine formula. The pigs fed 0.68% lysine gained faster and more efficiently. In the third trial, pigs were fed 0.58 and 0.78% lysine rations ad libitum and responded better to the 0.78% level. In the fourth experiment, the pigs were fed 0.68% lysine rations ad libitum and gained 0.74 kg/day, equal to the response to the 0.78% level in the previous trial.It was concluded that the lysine requirement for 23- to 57-kg pigs fed rations containing 3,330 kcal digestible energy/kg is about 0.7%. After they reached 57 kg, the pigs were fed 14 or 16% finisher rations. In general, responses to the high-energy rations tested were equal. Some carryover effects of grower rations on carcass characteristics were observed.

EFFECT OF FERMENTATION TIME IN THE ARTIFICIAL RUMEN ON THE RELATIONSHIP OF IN VITRO DIGESTIBILITY TO DIGESTIBILTY AND INTAKE OF HAY BY SHEEP

The digestibility and intake of several kinds of hay at several growth stages were measured with sheep. The in vitro digestibility was determined by a two-stage procedure. Because the in vitro digestibility of dry matter was unduly affected by a high solubility of the ash fraction, organic matter digestibility was the preferred criterion. In vitro digestibility was measured after fermentation times of 6, 12, 24, 48 or 96 hr. Significant correlations (P < 0.001) were found between in vivo and in vitro digestibility at each of these times. Near-maximal correlations occurred for most hays at 48 to 96 hr. Regressions for each duration were calculated and were used to estimate durations where equal in vitro and in vivo values should occur. Differences between kinds of hay and interactions between growth stages hindered improvement of the assay procedure by simple adjustments in fermentation duration.Optimal estimates of digestibility and intake occurred at the same fermentation durations. This was attributed to the recognized relationship between digestibility and intake of forage. A change of one unit in the in vitro digestibility was associated with an 18% greater change in intake of grass hay than of alfalfa hay, but at 70% digestibility both kinds of hay were eaten in equal amounts.The optimal fermentation duration for a general assay to predict digestibility and intake was about 48 hr. Further improvements appeared to require knowledge about differences in kinds and growth stages of hay, in their physical and chemical reaction to in vivo mastication and digestion as compared with grinding and in vitro digestion.

EFFECTS OF VARIOUS HEAT AND MOISTURE TREATMENTS ON MYROSINASE ACTIVITY AND NUTRITIVE VALUE OF SOLVENT-EXTRACTED CRAMBE SEED MEAL

Solvent-extracted crambe meal, uncooked, dry-heated, autoclaved or steam-stripped, was fed as 0, 5 or 10% of the diet to weanling mice. Ground rapeseed (1% of the diet) was fed in a cross-treatment as a source of myrosinase.Uncooked crambe meal significantly depressed (P < 0.05) feed intakes and gains. Heating by any method tested resulted in significant improvement, but feeding value remained below that of the casein-soybean protein control diet. The addition of the myrosinase source had little effect.In a second experiment, ground seed of crambe, rape and camelina (Crambe abyssinica Hochst., Brassica napus L. and Camelina sativa Crantz) were compared as myrosinase sources when incorporated 1:4 into cooked crambe meal and allowed to react overnight at room temperature with 0 or 30% moisture in the mixture. After this enzyme treatment, half of each mixture was autoclaved to destroy myrosinase prior to ration mixing and feeding.Appreciable hydrolysis of thioglucosides occurred in vitro at 30% moisture, resulting in marked growth depression. The feeding of active myrosinase similarly depressed animal responses, apparently through in vivo thioglucoside hydrolysis. All sources of enzyme were effective.The failure to obtain more enzyme response in the first experiment was attributed to lower enzyme concentration and inferior enzyme-substrate proximity during the time when conditions were otherwise appropriate for thioglucoside hydrolysis.

DICOUMAROL STUDIES: IV. ANTIDOTAL AND ANTAGONISTIC PROPERTIES OF VITAMINS K1 AND K3 IN CATTLE

Oral vitamin K3 was found to be a moderately effective antagonist to dicoumarol in cattle. Given as single massive doses, however, vitamins K1 (intravenous) and K3 (oral) displayed high antidotal properties, although vitamin K3 was much less effective. It was concluded that the most effective treatment for cattle suffering from "sweetclover disease" was the intravenous administration of vitamin K1 as a single massive dose of 2000 mg. This restored prothrombin times to near normal within 24 hours, with a minimum subsequent rebound. A less effective but still useful antidote was a massive oral dose of 5000 mg of vitamin K3.

THE FEEDING VALUE OF SOLVENT-EXTRACTED CAMELINA MEAL EFFECTS OF LEVELS FED, HEAT TREATMENTS AND FLAVOR SUPPLEMENTS

Camelina seed was ground, solvent-extracted, and fed at levels of 0, 5, 10, 15, 20 and 25% of the diet to weanling mice. Licorice (0 and 0.025%) was tested as a cross-treatment to modify flavor. Levels up to 10% resulted in no adverse effects on growth of mice but each increase in level beyond 10% resulted m a significant (P <.05) reduction in gains and feed intakes. Licorice was ineffective.In a second experiment 20 to 22% of camelina meal was fed m all diets. Raw meal was compared with dry-heated meal (12 hours, 135 °C), autoclaved meal (15 min, 1.2 kg/cm2), steam-stripped (2 hours, 110 °C) and a casein–methionine–supplemented control diet. In each case, four myrosinase-source supplements were added: nil, crambe seed, rapeseed, and camelina seed (Crambe abyssinica Hochst., Brassica napus L., and Cameline sativa Crantz).Destruction of myrosinase by any method of heating resulted in significantly better feeding value of camelina meal, but steam stripping was superior to dry heating or autoclaving.It was concluded that camelina meal is probably superior to rapeseed and crambe meals, in that more than 10% of raw meal is tolerated in the diet before growth depression occurs. Near maximum growth was obtained with myrosinase-free diets containing about 20% meal. Growth depression that occurred at the higher levels of intake exceeded that which could be accounted for by the content of volatile isothiocyanates.