Characteristics of ATSDR's adult and pediatric environmental neurobehavioral test batteries

In 1991 the Agency for Toxic Substances and Disease Registry selected a group of neurobehavioral tests to be used in the screening of individuals living near hazardous waste sites. Data from a review of 185 work site studies show that the Adult Neurobehavioral Environmental Test Battery (AENTB) is comprised of tests that have been used to study a wide range of toxic chemicals and that have proved to be capable of detecting impaired populations. Efforts to evaluate potentially impaired populations will be aided by an extensive planning and test administration manual. Progress toward the development of a pediatric counterpart (Pediatric Neurobehavioral Environmental Test Battery [PENTB]) is also reviewed.     

4-[(1H-imidazol-4-yl) methyl] benzamidines and benzylamidines: novel antagonists of the histamine H3 receptor

A series of amidine substituted phenyl-, benzyl-, and phenethylimidazoles based on the known H3 agonist SK&F 91606 (4) has been synthesized and tested as ligands for the histamine H3 receptor. Insertion of a phenyl ring between the imidazole ring and the amidine moiety produces antagonists. The benzyl series was found to be the most potent and was further investigated. Compounds 9c and 18 (entries 5 and 12, Table 1) are potent ligands for the H3 receptor with K(i) values of 16 nM and 7.2 nM respectively. In vivo, both compounds were shown to be equipotent to thioperamide (2), the standard H3 antagonist.     

Osmolality changes in perilymph after systemic administration of glycerin

Blood osmolality was altered in guinea pigs by intravenous administration of glycerin (glycerol). After glycerin administration, serum osmolality increased rapidly, reaching a plateau within 15 minutes. Perilymph osmolality lagged significantly behind the increase of serum osmolality and equalled serum osmolality only after one hour. While perilymph osmolality responded to changes of serum osmolality, there was some time lag noted in the response of perilymph, suggesting the existence of a blood-labyrinth barrier. It was observed that this barrier is permeably to glycerin and water, suggesting the possibility of transient reduction of hydrostatic pressure in the labyrinth by the injection of an osmotic agent into the systemic circulation.     

Gossypiboma of the abdomen

Intra-abdominal cysts may rise from a variety of organs. However, foreign-body reaction and cyst formation should be considered in the differential diagnosis. In this report, we describe the finding of a preoperatively undetected gossypiboma. A gossypiboma is a mass within the body that is composed of a cotton matrix; in this case, an unmarked laparotomy sponge. The evaluation, findings, and prevention of gossypiboma are discussed.     

Influence of retained austenite on the fatigue endurance of carbonitrided steels

The influence of retained austenite on the rotary bending fatigue endurance of carbonitrided specimens of two different steels is investigated. Results obtained in this work support the existence of a value of retained austenite for which the fatigue limit is maximum. A model for the influence of retained austenite, based on that generally accepted for superficial residual compressive stresses, is presented. According to this model, fatigue cracks could nucleate at different sites, surface or case bottom, in specimens with austenite contents at each side of the fatigue maximum, and this maximum should occur at lower values of retained austenite in notched specimens.     

Concrete/mortar water phase transition studied by single-point MRI methods

A total of 231 pigs were anesthetized and then scanned by DXA using a Lunar DPXL instrument. The weight of the pigs ranged from 5 to 97 kg (av. = 37.7 kg). Of the total, 98 pigs were scanned using the pediatric mode and 133 pigs were scanned using the adult mode. After scanning, the pigs were euthanized, the entire body homogenized by grinding, and analyzed chemically for fat, water, protein and total body mineral content. The mean value for the DXA total tissue mass (37.1 kg) was not significantly (P > 0.05, n = 231) different from the mean body weight. The mean DXA value for percent fat was 14.6 and was significantly less (P < 0.05) than the mean value (17.6%) measured by CHEM analysis. The greatest discrepancy occurred in pigs with < 15% body fat. From a prediction equation using the DXA R value [% fat = 493-349(DXA R value)], the DXA estimated percent fat was 18.0%, compared to 17.6% by CHEM analysis (P > 0.05). Using a prediction equation [g protein = -1.062 + 0.22(g DXA lean)], the DXA estimate for body protein content was 17.8%, compared to 17.1% (P < 0.05, n = 131) by CHEM analysis. The DXA estimate for body water content [g water = 508 + 0.74 (g DXA lean)] was 63.8%, compared to 62.6% (P < 0.05, n = 231) by CHEM analysis. The bone mineral content of 83 of the pigs measured by DXA was 2.40%, compared to 2.54% (P < 0.05, n = 83) estimated from CHEM analysis of total body ash [g bone mineral = g total body ash -0.0085(g DXA lean)].