Opioid-receptor blockade reduces nose-poke self-stimulation derived from medial entorhinal cortex

Rats were trained to nose-poke for intracranial self-stimulation (SS) with electrodes unilaterally implanted in the medial entorhinal cortex. The acute effects of naloxone (NX; 0.1-10 mg/kg, IP) on a continuous reinforcement schedule were determined. Reductions in the self-stimulation rates occurred only at moderate doses (median of individual changes = -36% at 1 and 5 mg/kg), whereas the high dose (10 mg/kg) was ineffective. None of the doses influenced operant behavior. These results are consistent with the hypothesis that endogenous opioid-opiate receptor mechanisms play a modulatory role in SS reward. Considering that NX was administered systemically the action of the drug on reinforcement levels may be mediated by a site distinct from the locus of stimulation.     

The reaction of skin to primers used in the "single-step" bonding systems

A large number of direct bonding systems have been introduced for use by dentists and dental hygienists. Although these agents are used for direct bonding of brackets to enamel, contact with skin, oral mucosa, and gingiva is not uncommon. These products have wide clinical use, but their biocompatibility characteristics have not been extensively investigated. The present study was undertaken to determine the effects of the primer component of Mono-Lok (Rocky Mountain) and the primer component of Control (Lancer Pacific) on skin. Three adult Macaca mulatta monkeys were used in the study. The skin on their backs was shaved and the primer component of Control, primer component of Mono-Lok, and saline solution were applied at different sites every 3 days for up to four applications. The skin was examined clinically and, 5 days after the last application, a biopsy was performed for histologic evaluation. The skin in contact with the primer component of Mono-Lok exhibited pronounced inflammatory changes and was characterized by swelling, vesiculation, and ulceration. Histologic observations confirmed these findings by showing a marked inflammatory cellular response characterized by eosinophils. In contrast to these findings, the skin in contact with the primer component of Control or saline solution exhibited normal architecture. Histologic observations supported this appearance and showed minimal inflammatory cell infiltration. These results show that there are differences in the biocompatibility of direct bonding systems and that further studies are needed to clarify their long-term effects on patients and dental personnel.     

CEA and CA 19.9: an evaluation by new statistical technics on a group of elderly patients

New parametric and non parametric statistical methods have been compared in the evaluation of experimental data of CEA and CA 19.9 using a brief program in BASIC. We have found that the distribution of the two markers is the same of that described in literature except for both the means that we have found being slightly higher than that ones described by other authors.     

Hexamethyldisilazane in preparation of retinal tissue for scanning electron microscopy

A new rapid procedure for desiccating frozen resin-cracked retinal tissue for scanning electron microscopy (SEM) which permits air-drying was found to compare favorably with tissues prepared by critical-point drying: Retinal tissue was fixed in 4% phosphate-buffered neutral formaldehyde, dehydrated by means of graded ethanol, embedded in Epon, cracked and washed in propylene oxide. For desiccation, the specimens were immersed in hexamethyldisilazane (HMDS), air-dried and finally sputter-coated. The method is time-saving, gives extended information in SEM, and the number of good specimens is increased.     

Various problems in the diagnosis and treatment of the broncho-obstructive syndrome

Clinico-x-ray-laboratory investigation, bronchoscopy were performed, respiratory function and ECG were studied in 212 patients with different forms of chronic bronchitis. Six groups of patients were defined with relation to the presence or absence of obstruction, its nature (permanent, transient), prevalence (small, medium and large bronchi), genesis of disease (inflammatory, allergic). The characteristics of the groups and their clinico-x-ray, functional and immunological features were presented. Treatment including methods of climatotherapy, exercise therapy, pharmacological agents (antibacterial, broncholithic and antihistaminic), physiotherapy and administered with relation to the defined groups, proved to be effective. The improvement of bronchial permeability was noted in 49.5% (ranging from 40.0 to 68.7% in different groups).     

Neonatal reference values for ionized calcium, phosphate and magnesium. Selection of reference population by optimality criteria

Thirty-one full-term newborn babies were investigated in order to establish reference values for ionized calcium. Only children fulfilling certain optimality criteria (with best possible maternal and infant conditions and uncomplicated pregnancy and delivery) were included. All infants were breast fed. Capillary blood for analysis of ionized calcium was collected by heel puncture on day 1 (6-36 h post partum, p.p.), day 3 (60-84 h p.p.) and day 5 (108-132 h p.p.). Ionized calcium was measured with a semi-automatic electrode system ICA 1 (Radiometer A/S, Copenhagen, Denmark). The reference ranges (mean +/- 2 SD) for days 1, 3 and 5 were 1.05-1.37, 1.10-1.42 and 1.20-1.48 mmol/l, respectively. The mean ionized calcium concentration on day 1 was significantly lower than on days 3 and 5. Reference values are also given for total calcium, magnesium and phosphate. We emphasize that it is impossible to calculate ionized calcium from total calcium or vice versa.