Oral contraceptive administration,interfemale relationships,and sexual behavior inMacaca fascicularis

The effects of oral contraceptive administration on the social relationships of adult female cynomolgus monkeys (Macaca fascicularis) were examined. Ten females were administered ethinyl estradiol/ethynodiol diacetate (Demulen), 10 were administered ethinyl estradiol/norgestrel (Ovral), and 10 served as a control group. The monkeys lived in social groups of 5 females each, and patterns of social interaction and social status were recorded. Interfemale relationships were also observed when a vasectomized male was placed in each social group for 50 min, once/week. During the latter observations, preliminary data on the effects of oral contraceptive treatment on sexual interaction were also collected. In the absence of the male, interfemale agonistic interactions and time spent alone were influenced by social status but not by oral contraceptive treatment. Time spent in passive body contact, an affiliative state, was reduced by Ovral treatment. In the presence of the male, dominant females aggressively interfered with the sexual interactions of subordinates. This aggression resulted in the termination of a greater proportion of the sexual interactions of subordinates than dominants in the control group only, indicating suppression of this type of interaction by oral contraceptive treatment. Other effects included a decreased frequency of ejaculation with Ovral-treated females. These results suggest that oral contraceptives may suppress certain types of female agonistic behavior (e.g., in the context of mate competition) and some oral contraceptives may interfere with sexual activity. More broadly, these findings indicate that intrasexual competition for access to mates may occur in females as well as males. This study was supported in part by NICHD Contract #N01-HD-32800 and by Grant #HL14164 from the National Heart, Lung and Blood Institute.     

Autosomal dominant retinitis pigmentosa mapping to chromosome 7p exhibits variable expression.

The genetic locus causing autosomal dominant retinitis pigmentosa (adRP) has recently been mapped in a large English family to chromosome 7p. Eight affected members of this family were studied electrophysiologically and psychophysically with dark adapted static threshold perimetry and dark adaptometry. The phenotypes observed fell into three categories: minimally affected with no symptoms, and normal (or near normal) electrophysiology and psychophysics; moderately affected with mild symptoms, abnormal electroretinograms, and equal loss of rod and cone function in affected areas of the retina; and severely affected with extinguished electroretinograms and barely detectable dark adapted static threshold sensitivities. The mutation in the gene on 7p causing adRP in this family causes regional retinal dysfunction with greatly variable expressivity ranging from normal to profoundly abnormal in a manner not explained by age.     

An approach to fractures of the midface: An interactive tutorial

Purpose: To describe an educational computer aided instruction program dealing with diagnosis and classification of facial fractures. Methods: A program was created for use on Macintosh computers using a graphic presentation package. This program allows for the display of high resolution digitized radiographic images and illustrations, along with integrated voice and text information. Users can interact with the program to review complex concepts or study additional cases. Case material was obtained from selected high quality plain radiographs and computed tomography (CT) scans obtained in the trauma center of one institution, and was scanned on a high resolution digital scanner with image parameters optimized for viewing on the Macintosh high resolution color monitor. Results: The program has been installed in the computer aided instructional laboratories or trauma centers at The University of Texas Health Science Center, Houston; The University of Alabama, Birmingham; Emory University School of Medicine, Atlanta, Georgia; and The University of North Carolina, Chapel Hill. The program is available to radiology residents and medical students rotating on the trauma radiology services at these institutions. Completion of the program requires 30–45 minutes. Conclusion: Based on our initial experience, the program has been used by residents in the training programs of all institutions with favorable results.     

Perceived risk as a factor influencing attitudes toward physically disabled children

The effects of perceptions of risk on attitudes toward handicapped children were studied. Five hundred twenty two nonhandicapped children between the ages of 8 and 19 were assigned to one of four experimental conditions in a basic 2×2 (Risk×Interview) paradigm. Some subjects were assigned to a high risk condition whereby if they indicated they would like to be friends with a handicapped peer, they were told that they might actually have to befriend a handicapped youngster who was about to enter their class; other subjects were not told about any personal involvement with the handicapped child. In the Interview factor, about half the subjects were informed that their attitudes would be known to other group members, the other half of subjects were told their attitudes would remain private. The 2×2 paradigm was studied with children at three ages levels: 8–11; 12–15; 16–19. Results revealed three significant main effects, generally supporting the hypothesis regarding the effects of risk factors.     

First and Second Generation Lithotripsy in Children: Results, Comparison and Followup

During a 5-year period 32 children and adolescents 4 to 18 years old underwent 35 extracorporeal shock wave lithotripsy (ESWL^* ) treatments for 37 calculi. The unmodified Dornier HM3 lithotriptor was used in 21 cases (60 percent) while the remaining cases were treated with the Siemen Lithostar lithotriptor. The HM3 necessitated general anesthesia in 67 percent of patients and the Lithostar necessitated intravenous sedation in 86 percent. The majority of pediatric lithotripsy treatments were performed on an outpatient basis (24) or during an overnight hospital stay (3) while 8 were done on an inpatient basis. Of the 37 stones treated with 1 ESWL session 68 percent resolved, 19 percent had residual fragments less than 4 mm., 8 percent had residual fragments greater than 4 mm. and 5 percent required an endoscopic procedure for resolution. When success rates by lithotriptor were examined no significant difference between the 2 machines was identified although the HM3 treated larger stones (p = 0.0499). There were no statistical differences in regard to success and the use of stents, patient age or stone location between the 2 lithotriptors. Three patients required adjuvant procedures, and complications and morbidity developed in 2 and 5, respectively. All children or parents were contacted for followup (range 7 to 67 months). One child required ESWL for a new stone while another passed a stone without intervention. Only 1 child with a residual fragment less than 4 mm. became symptomatic but needed no intervention while 1 of 3 with fragments greater than 4 mm. needed intervention. No patients required open or percutaneous intervention.     

Platelet dosing.

Many patients with thrombocytopenia require transfusion of platelet concentrates, and numerous factors may influence the observed response to transfusion. One factor gaining growing recognition in recent years is the consideration of the dose of platelets to administer. Review of the available data regarding the effect of platelet dose on transfusion outcome is presented in this summary, with attention to those situations that seem to require higher platelet doses. Appropriate dosing may not only improve the immediate response to transfusion, but also lead to a decrease in further platelet transfusion requirements. Recommendations supported by actual clinical data are outlined, but controlled studies are needed to determine optimum platelet doses for many common clinical situations.     

GM1 ganglioside partially rescues cultured dopaminergic neurons from MPP-induced damage: dependence on initial damage and time of treatment

GM1 ganglioside is believed to be important in promoting the recovery of neurons from injury. The present study assesses the ability of GM1 to repair or prevent the damage of dopamine neurons caused by the neurotoxin 1-methyl-4-phenylpyridinium (MPP⁺). Treatment of mesencephalic cell cultures with 2.5 μM MPP⁺ resulted in the loss of 30% of tyrosine hydoxylase (TH) immunoreactive neurons. In contrast, cultures administered 100 μM GM1 ganglioside for 3 days after toxin treatment contained nearly control numbers of TH⁺ neurons (97%). This reparative effect of GM1 was reflected in parallel increases in TH enzyme activity, dopamine and dopac levels. Cultures sustaining greater insult from higher doses of MPP⁺ (5.0–10.0 μM) did not benefit from ganglioside treatment, suggesting that rescue by GM1 depended on the degree of initial damage to cells. Moreover, the timing of ganglioside treatment was critical; pretreatment with GM1 alone did not prevent or attenuate the damage caused by subsequent incubation in 2.5 μM MPP⁺.