Parental influences on childhood fitness and activity patterns.

The purpose of this study was to determine the effect of parental attitudes and self-reported exercise habits on the fitness and activity levels of their children. One parent from each of 1,253 families was asked about exercise habits and completed the Exercise Benefits and Barriers Scale (EBBS) to determine their personal attitudes toward exercise. The children completed a self-reported activity questionnaire (SRA) and had their aerobic power predicted using a cycle ergometer test. Multiple regression indicated that the parents' EBBS scores were weakly associated with the child's maximal oxygen uptake (VO2max); the mothers' association was significant, but the fathers was not. The children's SRA scores were not correlated with parents' attitudes or exercise habits. These results suggest either that factors other than parental attitudes and exercise habits are more influential in determining the fitness and activity levels of children or that the instruments lack precision. Thus, to improve the cardiovascular fitness of children, we need to examine factors in the child's environment that may be more influential than parental attitudes and examples.

Effect of reduced sodium chloride concentration and tetrasodium pyrophosphate on pH, water-holding capacity and extractable protein of prerigor and postrigor ground beef.

The effect of tetrasodium pyrophosphate (TSPP) (0, 0·25, 0·5% w/w) alone or in combination with salt (NaCl) (0, 0·5, 1·0% w/w) on water-holding capacity (WHC), pH, the ratio of absorbance at 250 nm over the absorbance at 260 nm (R-values) and 150m CaCl extractable protein (EP) was studied in prerigor and postrigor sternomandibularis homogenates over time. The 0 h samples were defined as when the NaCl was incorporated with the muscle. R-values verified that 0 h samples were in a prerigor or postrigor state. In prerigor homogenates, increasing phosphate concentration increased the time required to reach ultimate pH. Ultimate pH values of prerigor homogenates containing phosphate were lower (P < 0·05) than homogenates without phosphate and similarly treated postrigor homogenates. After six hours, no differences (P > 0·10) were noted in EP or WHC at different phosphate concentrations when averaged over NaCl concentrations in prerigor homogenates. With increasing phosphate concentration of postrigor homogenates, there was an increase (P < 0·05) in pH and EP at the initial sampling time. However, 0 and 0·25% phosphate WHC values could not be differentiated (P > 0·10). Results of this study indicate no advantages, after six hours post mortem, to using TSPP alone or in combination with NaCl in prerigor meat homogenates at concentrations added in this study.

Effect of sodium chloride concentration on pH, water-holding capacity and extractable protein of prerigor and postrigor ground beef.

Fifteen beef cattle of similar age and management history were randomly allotted by slaughter days into three groups. Paired sternomandibularis were removed immediately following bleeding and trimmed of visible fat and connective tissue. They were randomly labelled as prerigor and postrigor and assigned to a 0, 0·5, 1·0, 2·0 or 4·0% NcCl treatment. Water-holding capacity (WHC), pH, the ratio of absorbance at 250 nm over the absorbance at 260 nm (R-values), and 1·0m NaCl extractable protein (EP) were monitored over treatment times. The 0 h samples were defined as when the NaCl was incorporated with the muscle. R-values verified that 0 h samples were in the prerigor or postrigor state. Ultimate pH remained higher (P < 0·05) in prerigor homogenates with increasing NaCl concentration. EP and WHC were higher (P < 0·05) in prerigor than in postrigor homogenates with 2 and 4% NaCl at all time periods. Prerigor homogenates containing 0·5 and 1·0% NaCl had higher (P < 0·05) WHC at 12, 24, 24, 48 and 96h than similarly treated postrigor homogenates and as high or higher WHC than any postrigor treatment. Results of this study indicate an advantage to using low NaCl concentrations in prerigor salted beef.

Cerebral CT scan abnormalities in cholestatic and hepatocellular disease and their relationship to neuropsychologic test performance.

Forty-nine nonalcoholic cirrhotic patients, on whom cranial CT scans were available, were administered a battery of neuropsychological tests. Although none of the subjects exhibited clinical signs or symptoms of hepatic encephalopathy, quantification of the CT scan image implicated cerebral edema and cortical atrophy. In addition numerous significant correlations were observed between the CT variables and neuropsychological test performance. The findings are conjectured to reflect previously unrecognized cerebral morphologic changes associated with chronic subclinical portal-systemic encephalopathy.

Role of norepinephrine in the rabbit ganglionectomy response.

Superior cervical ganglionectomy (SCG) produced delayed mydriasis and ocular hypotension in rabbits. Norepinephrine (NE) was lost from the iris-ciliary body exponentially with onset of about 11 h. NE in aqueous humor peaked at twice control levels (from 7 to 14 ng/ml) at 16.5 h and subsequently declined to below control levels by 24 h. Intracameral administration of radiolabeled NE (150 ng) to control eyes resulted in a calculated outflow of 1.6 microliter/min, comparable to that seen with fluorescein (1.7 microliter/min). NE administered to ganglionectomized eyes (26 h after surgery) resulted in a calculated outflow of 3.1 microliter/min. These results suggest that mydriasis following SCG may be due to NE released from degenerating sympathetic nerve endings. However, NE concentration in the aqueous humor appears inadequate to produce the delayed increase in outflow observed in rabbits after SCG.

Use of Antioxidant-Coated Salts as N-Nitrosamine Inhibitors in Dry- and Brine-Cured Bacon 1.

Several experiments were completed to further evaluate use of α-tocopherol-coated salts as inhibitors of N-nitrosamine formation in fried bacon. Studies with dry-cured bacon prepared with various levels of α-tocopherol indicated that the chemical did not contribute to formation of N-nitrosodimethylamine (NDMA). N-Nitrosopyrrolidine levels for the α-tocopherol-treated bacon samples were generally below 5 µg/kg, which represents an average reduction of approximately 70%. Experiments were also done to evaluate the role of lecithin as a possible precursor of NDMA in brine-cured bacon. At concentrations used to disperse α-tocopherol in the curing brine, lecithin did not contribute to NDMA formation in bacon prepared with α-tocopherol-coated salts.

Evidence for two distinct sympathoinhibitory bulbo-spinal systems.

Yohimbine hydrochloride (0.5 mg/kg, i.v.) caused a long-lasting potentiation of electrodermal (sympathetic-cholinergic) reflexes in intact anaesthetized and decerebrate unanaesthetized cats. Transection of the cervical spinal cord also resulted in an increased amplitude of the sudomotor reflex in unanaesthetized decerebrate preparations. Depletion of monoamines in the CNS by pretreatment with reserpine (5 mg/kg, i.p.) and alpha-methyl-p-tyrosine (2 X 300 mg/kg, i.p.) reduced the concentrations of norepinephrine, dopamine and serotonin to less than 93% of control levels in the thoracic spinal cord. In monoamine-depleted preparations, yohimbine no longer facilitated the reflex amplitude whereas the effect of spinal transection was not altered. These results suggest that there are two distinct sympathoinhibitory systems in the lower brain stem that converge on spinal sympathetic neurons, one of which is monoaminergic and one of which is not. Evidence for the baroreceptor-independent nature of these descending inhibitory systems is discussed.

Use of a sympathetic-cholinergic system in the analysis of sympatho-inhibition produced by clonidine and some congeneric derivatives of clonidine.

The effects of clonidine and five analogs of clonidine were tested with regard to their ability to depress centrally and peripherally evoked electrodermal responses (EDR) in control cats, as well as in animals pretreated with yohimbine hydrochloride. With the exception of St-91, all of the clonidine-like substances selectively reduced the amplitude of centrally (hypothalamic) evoked responses in a dose-dependent fashion. Clonidine was found to have no significant inhibitory effect at the level of the sympathetic ganglion. The order of central nervous system sympatho-inhibitory potency of these compounds was clonidine (St-155) greater than St-375 greater than St-606 greater than St-600 greater than St-608 much much greater than St-91. Prior treatment with yohimbine hydrochloride (0.5 mg/kg i.v.) antagonized the depressant effect of all of these drugs. These results indicate that clonidine and the clonidine congeners tested (with the exception of St-91) all produce sympatho-inhibition by an action on a CNS alpha-adrenergic mechanism and demonstrate the usefulness of this electrodermal model system for the analysis of drugs affecting central sympathetic reactivity.

Leptospirosis in Nepal.

We present here a case report of a suspected leptospiral infection in a Nepali soldier, and the results of a serological survey of 188 residents of Eastern Nepal that indicate the infection may be common there. This is the first report of leptospirosis in Nepal although it is known to affect man and animals in most of the temperate and tropical regions of the world, and apparently occurs widely in India (Das Gupta, 1938; Khanna & Iyer, 1971).

Effects of clonidine and chlorpromazine on a sympathetic-cholinergic reflex.

Intravenous administration of clonidine and chlorpromazine resulted in a dose-dependent inhibition of the amplitude of reflexly evoked electrodermal responses in intact and spinal cats. Yohimbine pretreatment (0.5 mg/kg, i.v.) antagonized the effects of clonidine but not chlorpromazine in both preparations. These findings confirm and expand previous observations that both clonidine and chlorpromazine inhibit the amplitude of centrally evoked responses in this sympathetic-cholinergic system. In addition, both drugs appeared to have a spinal site of action. The antagonism of the effects of clonidine by yohimbine suggests that the mechanism of the action of clonidine may be a result of activation of central inhibitory alpha-adrenergic receptors. The failure of yohimbine to antagonize the effects of chlorpromazine suggests that clonidine and chlorpromazine may depress these sympathetic reflexes by different mechanisms.

Some physiologic characteristics of the electrodermal reflex in the cat.

The amplitudes of electrodermal reflexes evoked in intact cats were compared under a variety of anesthetic conditions. Electrodermal reflexes were elicited in both decerebrate and spinal preparations with and without anesthesia. Reflex amplitude was significantly depressed in the anesthetized preparation after decerebration or spinal transection. In contrast, spinal transection performed after decerebration in unanesthetized preparations significantly increased the amplitude of the reflex. The evidence presented in this study supports the concept of a primarily inhibitory lower brainstem system with regard to this reflex. The relative stability of the reflex amplitude in the anesthetized cat suggests that this reflex system could be useful in the analysis of the effects of drugs acting on the central nervous system.

Epinephrine inhibition of the electrodermal response in the cat.

Intravenous administration of epinephrine results in a dose-dependent inhibition of the peripherally evoked electrodermal response (EDR) in the cat. The magnitude of this depression of the EDR was greater when the responses were evoked by a single shock than by a train of shocks (10-12 Hz). The observation that this epinephrine-induced inhibition is antagonized by phentolamine suggests that an alpha-adrenergic mechanism is involved. It is unlikely that this effect is due primarily to the vascular actions of epinephrine because the inhibition of the EDR was much more prolonged than was the pressor action. Angiotensin was ineffective in inhibiting these responses.