Behavior of caregivers to protect their infants from exposure to the sun in Queensland, Australia.

Exposure to the sun by infants has been demonstrated to increase the risk of the development of melanoma and other skin cancers later in life. A cohort of 508 women who delivered healthy Caucasian babies were followed up at 1 year to determine their knowledge, attitudes and practices regarding sun protection towards themselves and their child. In addition, the 1-year-old infants were assessed by a trained nurse for the number of nevi they had on their skin. Results indicate caregivers reported a high level of sun-protection practices towards their child, with 93% of the caregivers reporting usually or always placing the child in the shade when going outside. Further, 81% of the caregivers reported usually or always placing a hat on the child, while 64% reported usually or always applying sunscreen to the child's exposed skin. Interestingly, only 61% of the caregivers reported that they stayed in the shade to reduce sun exposure and only 42% wore a hat when out in the sun. Mother's own personal sun-protection methods predicted the method of sun protection that she would most likely use for the child. While children appear to be reasonably protected from the sun, they are influenced by their mother's own behaviors.

Effects of purine and pyrimidine nucleotides on intracellular Ca2+ in human eosinophils: activation of purinergic P2Y receptors.

BACKGROUND: Extracellular adenosine 5'-triphosphate (ATP) increases human eosinophil intracellular Ca(2+) concentration; the mechanism of action is not fully known. ATP, a physiologic regulator, acts through 2 purinergic receptor types: cation channels (P2X) and G protein-coupled receptors (P2Y). OBJECTIVE: This study is aimed at identifying the functional purinergic receptors in human eosinophils. METHODS: The relative potency of ATP, uridine (UTP), cytidine (CTP), and inosine (ITP) 5'-triphosphates (P2Y agonists); 2-methylthio-ATP (P2Y(1) agonist); and 2 P2X agonists, alpha,beta-methylene-ATP and beta,gamma-methylene-ATP on intracellular Ca(2+) concentration was examined in Ca(2+)-sensitive Fura-2-labeled human eosinophils. For comparison, ATP effects were similarly studied in human neutrophils. P2X/P2Y mRNA expression in cells was examined by reverse transcription and PCR. RESULTS: The nucleotide potency order was UTP > or = ATP > ITP >>> 2-methylthio-ATP > alpha,beta-methylene-ATP = beta,gamma-methylene-ATP = CTP = 0 in eosinophils. Pertussis toxin (500 ng/mL) pretreatment abolished the effect of lower (10(-6) mol/L) but not higher (10(-5) mol/L) concentrations of ATP in eosinophils, whereas it attenuated the effects of 10(-4) mol/L ATP in neutrophils. The phospholipase C inhibitor U73122 (2 micromol/L) partially inhibited the effect of ATP in eosinophils but totally blocked it in neutrophils. Both cells constitutively express mRNA for P2X(1), P2X(4), P2X(5), P2Y(1), and P2Y(2), but not P2X(7), with much weaker expressions of P2X(4) and P2X(5) in neutrophils. Eosinophils cultured with the T(H)1 cytokine, IFN-gamma, expressed mRNA for P2X(7), a receptor linked to apoptosis. CONCLUSIONS: These results suggest that the P2 purinergic receptor signal transduction pathways in eosinophils and neutrophils are different and are mediated by more than 1 subtype of functional P2Y receptors.

Tuberculosis. Part I.

Tuberculosis has been a disease of human beings for thousands of years. In recent times it has waxed to become the feared White Plague of the eighteenth and nineteenth centuries and waned under the impact of effective chemotherapy until its elimination seemed possible by the early twenty-first century. The resurgence of tuberculosis in the past 10 to 15 years, caused by unanticipated events such as the appearance of the human immunodeficiency virus and deteriorating social conditions, also brought with it the problem of multiple drug resistance. Control measures such as tuberculin skin testing, perhaps somewhat forgotten when tuberculosis seemed to be a disease of the past, again became first-line defenses against spread of the disease. Environmental controls must be well understood and used effectively. Diagnosis of tuberculosis requires knowledge of the strengths and shortcomings of the various diagnostic methods and experience in their use. Practitioners are cautioned to remember that no diagnostic method, by itself, can be relied on to confirm or rule out tuberculosis. Well-tested diagnostic methods of chest radiograph, tuberculin skin testing, smear, and culture have been recently supplemented by rapid diagnostic tests based on amplification of bacterial RNA and DNA. More invasive diagnostic methods are sometimes required to diagnose extrapulmonary disease. Two-drug up to seven-drug therapy may be indicated for a case of tuberculosis, depending on evidence of the presence of multiple drug resistance. Duration of treatment can range from 6 to 12 months, also depending on identification of drug-sensitive or drug-resistant organisms. Failure of compliance can be a significant problem in patients who are homeless, or drug abusers, or who for various reasons cannot or will not complete a course of therapy. Directly observed therapy is strongly recommended for these patients, and for assistance in its administration the physician must cooperate with the local or state health department. The health department also must be notified whenever a case of tuberculosis is identified.

Help-seeking behaviors of people with sexual problems.

Help-seeking activities associated with the sexual problems of community respondents (N = 503) were studied. Major findings include (i) a majority of respondents reported some form of social help-seeking from predominantly informal rather than professional helpers; (ii) a significant increase over early adulthood in the likelihood of reporting a dyadic sexual problem was evidenced, however there was no parallel change in help-seeking behaviors with age; (iii) help-seeking from intimates was associated with obtaining help from other informal contacts; (iv) help-seeking from extrafamilial, but not familial, supports was found to covary with income, and (v) a "normative" sequence to help-seeking behaviors was identified. Also discussed is the present work's relevance to research on human immunodeficiency virus transmission.

Brain areas involved in production of morphine-induced locomotor hyperactivity of the C57B1/6J mouse.

Previous studies reveal a dose-dependent increase in locomotor activity of the C57B1/6J mouse after administration of morphine or amphetamine. Concurrent partial lesions of both the dorsomedial caudate and lateral septal nuclei resulted in a significant decrease in morphine-induced, but not amphetamine-induced, hyperactivity. Concurrent partial lesions of the nucleus accumbens and stria terminalis produced only a nonsignificant decrease in the morphine-induced hyperactivity. Lesions of the individual brain structures did not significantly affect the morphine-induced locomotor hyperactivity. Microinjections of the opiate antagonist naloxone into discrete portions of the caudate and septal nuclei produced suppression of the morphine-induced hyperactivity response without affecting the hyperactivity caused by amphetamine injections. Only a slight suppression of morphine-induced locomotion was produced when naloxone was injected into the nucleus accumbens and stria terminalis. These data suggest that portions of the caudate and septum may be involved in the mediation of morphine-induced hyperactivity in the C57B1/6J mouse.

Estradiol and progesterone suppress feeding induced by 2-deoxy-D-glucose.

The feeding response to 2-deoxy-d-glucose (2DG) was measured in gonadally intact females (NORM) during estrus (EST) or diestrus (DIES) and in ovariectomized (OVEX) rats following injections of estradiol benzoate and progesterone (HORM) or oil (OIL). In both groups the response to 2DG under conditions of EST or HORM was significantly suppressed relative to DIES or OIL. The suppressant effect of hormones on 2DG feeding was not accounted for by the suppressant effects of ovarian hormones on ad lib feeding or a function of the body weight of the subject. The results are discussed in the context of ovarian hormonal effects on glucostatic control of feeding.

The effects of amphetamine or caffeine on the response to glucoprivation in rats with rostral zona incerta lesions.

Lesions in the rostral zona incerta (ZI) of male albino rats severely impaired feeding responses to 2-deoxy-D-glucose (2DG) and drinking responses to hypertonic saline during the first month after surgery. There was evidence of recovery 6 months after surgery but the magnitude of the improvement was small and severe impairments persisted in most subjects. A small but significant deficit in the feeding response to insulin persisted unabated after the 6-month recovery period. Caffeine or amphetamine pretreatment, but not apomorphine, increased ad lib feeding as well as the response to low doses of 2DG in rats with ZI lesions as well as in controls. The increased feeding response to 2DG after caffeine or amphetamine was larger than the sum of the effects of 2DG alone plus the effect of caffeine or amphetamine alone.

Supersensitivity to norepinephrine or dopamine antagonists after knife cuts that produce aphagia and adipsia in rats.

Aphagia and adipsia of equivalent duration were produced by knife cuts along the lateral border of the hypothalamus (PH cuts), or the medial surface of the globus pallidus (MP cuts) in male albino rats. Striatal dopamine (DA) was reduced by 75% in animals with PH cuts but only 50% by MP cuts. Hypothalamic norepinephrine was reduced 25% by PH cuts and was unaffected by MP cuts. Aphagia and adipsia were positively correlated with DA depletions only in rats with PH cuts. Presurgical catecholamine depletions produced by chronic injections of alpha-methyl-p-tyrosine did not alter the duration of aphagia or adipsia resulting from these knife cuts. However, following recovery of ingestive behavior, rats with PH and MP cuts were supersensitive to the anorexic effects of the dopamine-beta-hydroxylase inhibitor, diethyldithiocarbamate. Exaggerated anorexia was also observed after DA blockade by haloperidol or alpha-adrenergic blockade by phenoxybenzamine. The most pronounced effects of catecholamine blockade were observed in rats with PH cuts.

Regulatory deficits after surgical transections of three components of the MFB: correlation with regional amine depletions.

Parasagittal knife cuts along the lateral border of the diencephalon (PS), coronal cuts across the lateral (LMFB) or medial (MMFB) components of the medial forebrain bundle reproduce most of the persisting deficits in responding to glucoprivic and hydrational challenges that characterize rats with lateral hypothalamic lesions or intracranial injections of 6-hydroxydopamine (60HDA). Each of these cuts produced a differnet pattern of regulatory deficits, suggesting that individual components of the LH syndrome may be mediated by different neural substrates. This interpretation is supported by the results of our correlational analysis of the relationships between specific behavioral and biochemical effects of our cuts. For example, feeding responses to insulin were reliably correlated with striatal DA concentrations but feeding responses to 2-deoxy-d-glucose (2DG) were not. Water intake during periods of food deprivation was reliably correlated with striatal DA but water intake after an experimental osmotic challenge was not. Only one of the common persisting deficits (impaired feeding response to peripheral injections of insulin) was positively correlated with the duration of aphagia and adipsia.

A correlational analysis of the effects of surgical transections of three components of the MFB on ingestive behavior and hypothalamic, striatal, and telencephalic amine concentrations.

A retractable wire knife was used to transect medial or lateral components of the MFB or its lateral projections to the striatum and amygdaloid complex. All cuts produced significant depletions of NE, DA, and 5-HT from telencephalon and striatum but little or no effect on hypothalamic NE or 5-HT. Two of our cuts resulted in aphagia and adipsia, the third in hyperphagia and obesity. A detailed correlational analysis of the magnitude and direction of the behavioral and biochemical consequences of our cuts indicated that the ingestive behavior of all of our experimental animals (including animals which had been aphagic and adipsic after surgery as well as animals which were hyperphagic and obese) was positively correlated with the concentration of DA in striatum and telencephalon and negatively correlated with telencephalic 5-HT. Less consistent evidence for facilitatory noradrenergic influences on food intake was also obtained. Our results suggest that the regulation of food intake may be the result of an interaction between telencephalic serotonergic mechanisms and dopaminergic pathways which exert opposite effects on ingestive behavior.

Disinhibitory effects of intrahippocampal of intrahypothalamic injections of anticholinergic compounds in the rat.

The effects of intrahippocampal or intrahypothalamic injections of anticholinergic compounds on operant responding were observed in a multiple schedule paradigm consisting of reinforced, punished, and nonreinforced components and on a punished ingestive passive avoidance task. The pattern of results suggests that cholinergic components of the hippocampus and hypothalamus mediate responding suppressed by nonreinforcement but not by punishment. The data are discussed with reference to Carlton's proposed central cholinergic inhibitory mechanisms.