Sexual precocity: sex incidence and aetiology.

The aetiology of 197 girls and 16 boys presenting with sexual precocity was reviewed. Ninety one girls and four boys had central precocious puberty (M:F 23:1); a cause was identified in all the boys but in only six girls. All boys with precocious puberty need detailed investigation; in girls investigation should be based on clinical findings, particularly the consonance of puberty.

Bilateral communicating bronchopulmonary foregut malformations in an infant with multiple congenital anomalies.

Communicating bronchopulmonary foregut malformations (BPFMs) are uncommon congenital lesions which usually present in infancy with respiratory distress, which is exacerbated during feeding. We present an unusual case of bilateral oesophageal BPFM in an infant with multiple congenital anomalies.

Cognitive, behavioral, and family factors in the differentiation of depressive and anxiety disorders during childhood.

Contribution of cognitive, behavioral, and family environment variables to the differentiation of depressive and anxiety disorders in children was explored. Fifty-nine children from Grades 4-7 (14 diagnosed with a depressive disorder, 16 diagnosed with depressive and anxiety disorders, 11 diagnosed with an anxiety disorder, and 18 nondisturbed controls) completed measures of the depressive cognitive triad, depressive cognitions, social skills, family environment, and maladaptive family messages. Results of a stepwise discriminant function analysis indicated that 2 discriminant functions composed of 7 variables from the cognitive, behavioral, and family environment domains accounted for 91% of the between-groups variance.

Social-skills interventions with adolescents. Current issues and procedures.

During adolescence, the interpersonal interactions and behaviors necessary for successful social functioning become increasingly complex. In recent years, social-skills training with adolescents has made a variety of advances beyond basic skill acquisition toward techniques designed to promote generalization and maintenance of an effective interpersonal repertoire. This article reviews relevant empirical literature for current issues and procedures in social-skills training with adolescents, including use of social-skills interventions for a variety of adolescent populations and problems, use of innovative and promising intervention procedures, and issues regarding generalization and social validity of intervention procedures.

Resistance to Acetolactate Synthase-Inhibiting Herbicides in Annual Ryegrass (Lolium rigidum) Involves at Least Two Mechanisms.

WLR1, a biotype of Lolium rigidum Gaud. that had been treated with the sulfonylurea herbicide chlorsulfuron in 7 consecutive years, was found to be resistant to both the wheat-selective and the nonselective sulfonylurea and imidazolinone herbicides. Biotype SLR31, which became cross-resistant to chlorsulfuron following treatment with the aryloxyphenoxypropionate herbicide diclofop-methyl, was resistant to the wheat-selective, but not the nonselective, sulfonylurea and imidazolinone herbicides.

Differential plasma duration of antiplatelet-activating factor and antihistamine activities of oral Sch 37370 in humans.

Preclinical studies have established that Sch 37370 (1-acetyl-4-(8-chloro-5,6-dihydro-11H-benzo[5,6]-cyclohepta [1,2-b]pyridin-11-ylidene)piperidine) is an orally active antagonist of platelet-activating factor (PAF) and histamine H1-receptors with potential therapeutic use in the treatment of asthma. To evaluate the efficacy and duration of anti-PAF and antihistamine actions of oral Sch 37370 in humans, a single dose (5 mg/kg) of Sch 37370 was given orally to each of 10 male subjects in a placebo-controlled, double-blind crossover study. Blood samples were drawn before and at various times (2 to 48 hours) after Sch 37370 or placebo.

Cross-Resistance to Herbicides in Annual Ryegrass (Lolium rigidum) : II. Chlorsulfuron Resistance Involves a Wheat-Like Detoxification System.

Lolium rigidum Gaud. biotype SLR31 is resistant to the herbicide diclofop-methyl and cross-resistant to several sulfonylurea herbicides. Wheat and the cross-resistant ryegrass exhibit similar patterns of resistance to sulfonylurea herbicides, suggesting that the mechanism of resistance may be similar.

Effectiveness of a peer-helper intervention to increase children's social interactions. Generalization, maintenance, and social validity.

Peer-mediated interventions are being used increasingly with a variety of populations. This study examined the impact of a peer-helper intervention on the low rates of prosocial interactions of three-elementary-school children. Two peers from each child's classroom were trained as helpers to increase the social interactions of the socially isolated children.

Predictor variables related to the classification of learning disabilities.

Psychoeducational assessment variables for high school students were subjected to a discriminant function analysis. Variables predictive of learning disability classification were spelling, IQ, and a student interview question.

Antihypertensive effect of dilevalol is directly related to dose and plasma concentrations.

Dilevalol is a novel antihypertensive agent combining vasodilation due to selective beta 2-adrenergic receptor agonism with nonspecific beta antagonism. To determine the relation of dilevalol dose and plasma concentration to antihypertensive effect, dilevalol (n = 15) or placebo (n = 3) was administered to 18 hypertensive subjects. The study was performed under blinded conditions during a 21-day hospitalization after a 3-week drug-free outpatient phase.

Toxicology Studies of Irradiation-Sterilized Chicken.

Results of nutritional, genetic, and toxicological studies of shelf-stable chicken sterilized by ionizing radiaiton are presented. No evidence of genetic toxicity or teratogenic effects in mice, hamsters, rats, and rabbits was observed. There was an unexplained reduction in the hatchability of eggs of Drosophila melanogaster reared on gamma-irradiated meat.

Lymphomas: membrane markers and cell flow cytometric diagnosis.

Lymphocytes are characterized by membrane markers which, in part, reflect biological and functional activity. This is particularly true for T lymphocyte subsets identified by monoclonal antibodies. The B lymphocytes can be identified but in a more general manner.

Immunity during pregnancy: lymphocyte subpopulations and mitogen responsiveness.

Many hypotheses have been proposed to explain the alteration of maternal immune status that allows the fetus to escape rejection. Published data using monoclonal antibodies have stated that there are small variable reductions in circulating T-lymphocytes and little or no change in helper-to-suppressor ratios. Specific decreased levels of helper T-cells have been claimed by other workers.

Effect of cryopreservation on lymphocyte markers evaluated by monoclonal antibodies.

Lymphocytes were frozen at a density of 5 to 10 X 10(6) cells per ml at 1 degree C per minute in a programmable liquid nitrogen freezer. T-subsets were determined by using monoclonal antibodies. A fluorescein-conjugated polyvalent antisera with B-cell specificity was used to define B-cells.

The effect of exposure of acetylcholinesterase to 2,450-MHz microwave radiation.

The effect of 2,450-MHz pulsed microwave radiation on the enzyme activity of membrane-free acetylcholinesterase was studied while the enzyme was in the microwave field. We found no significant effect of microwave radiation on enzyme activity using a wide variety of power densities, pulse widths, repetition rates, and duty cycles. This suggests that simple, direct modification by microwave energy of acetylcholinesterase structure and enzymic activity is not related to microwave alteration of acetylcholinesterase central nervous system levels.

Menogaril: a new anthracycline agent entering clinical trials.

Menogaril [menogarol, 7(R)-O-methylnogarol, 7-OMEN] is a new anthracycline agent which was chosen for clinical trials based on: broad spectrum activity against a panel of murine tumors, lower cardiotoxicity than doxorubicin in the chronic rabbit model, differences in biochemical effects from other anthracyclines suggesting a possible difference in mechanism of action, murine antitumor activity by oral as well as parenteral routes. Biochemical studies indicated that, in comparison to doxorubicin, menogaril is bound weakly to DNA, inhibits RNA synthesis less, and has different cell cycle phase-specific cytotoxicity. Pharmacology studies in the mouse and dog using HPLC analytical methodology have shown multiexponential clearance from plasma and metabolism of menogaril to a material which co-chromatographs with N-demethylmenogaril in addition to at least two other metabolites of unknown structure.

Photodestruction of acetylcholinesterase.

Ultraviolet irradiation of 11S acetylcholinesterase (acetylcholine acetylhydrolase, EC 3.1.1.

Acridine araphanes: a new class of probe molecules for biological systems.

The bis-acridine ring system forms the basis for new biophysical probes of novel stereochemistry. Spectral data indicate that certain alkylene bridged bis-9-aminoacridines have a parallel plane conformation of predictable interplane distance. The parallel plane conformation is independent of solvent and thus is different from nucleic acid systems.

Inhibition of acetylcholinesterase by TX-100.

At high detergent concentrations, approximately the equivalent of 2 micelles of TX-100 reversibly bind to acetylcholinesterase and fully inhibit the enzyme. This result suggests that the appropriate lipid environment might regulate this neuronal enzyme's function.

Megavitamins for minimal brain dysfunction. A placebo-controlled study.

Preliminary to a stimulant comparison study, 31 children with minimal brain dysfunction randomly received either placebo or a megavitamin combination. During a two-week trial, only two children responded so well that stiumlants were not considered necessary; both were in the placebo group. Change scores from pretest to posttest on four blind ratings by teachers and parents did not show a significant difference between the placebo and vitamin groups.

Evidence that eel acetylcholinesterase is not an integral membrane protein.

Detergent binding studies indicated that the neural enzyme, acetylcholinesterase, did not exhibit the properties of an integral membrane protein. The 11S form was isolated by affinity chromatography from a tryptic digest and the 14S and 18S forms in like manner from an undigested preparation. Studies were performed with [3H]TX-100 to determine the extent of binding by these forms and with catalase and human low density lipoprotein as reference proteins.