Alternative routes of immunization for the induction of experimental autoimmune uveoretinitis (EAU) in rodents: a comparison

Experimental autoimmune uveoretinitis (EAU) in rodents is a widely used model of ocular autoimmunity. EAU has traditionally been elicited by injecting the uveitogenic protein in complete Freund's adjuvant (CFA) into the footpad(s) (FP). Because this route of immunization causes severe arthritis and inflammation, it is being banned by many institutions and investigators are switching to the subcutaneous (SC) route. However, there are no studies that systematically compare the outcome of these two immunization routes using defined clinical, histopathological and immunological criteria. We therefore undertook to compare the FP and SC routes of immunization in the Lewis rat and in the B 10. A mouse models of EAU. Animals were immunized with interphotoreceptor retinoid-binding protein (IRBP) or the retinal soluble antigen (S-Ag) in CFA, either by the traditional FP route or by the SC route. The parameters studied were kinetics and severity of EAU by clinical observation and by histopathology, respectively, as well as immunological responses by delayed-type hypersensitivity (DTH), serum antibody titers and lymphocyte proliferation to the uveitogen. In mice immunized with graded doses of IRBP, development of disease induced by the FP and SC methods had essentially identical kinetics. However, the SC method resulted in a somewhat higher incidence and severity of disease as well as higher DTH at the lower antigen doses. Antibody titers tended to be higher with FP immunization. In rats immunized with S-Ag, kinetics and severity of disease, DTH, proliferative responses of draining lymph node cells to the immunizing antigen, and serum antibody titers induced by FP and SC methods were similar. In rats immunized with IRBP, SC immunization resulted in somewhat higher responses across the board than FP. We conclude that at higher doses of antigen disease scores and immunological responses in animals immunized SC are comparable to those of FP-immunized animals. At limiting doses of antigen, however, the SC route appears to result in more severe disease than the traditional FP method.     

Variations in the behavioral responses to apomorphine in different strains of rats

The present experiments compared patterns of locomotor activity during repeated acclimation sessions and determinations of locomotion and stereotypy elicited by administration of the direct dopamine receptor agonist apomorphine in five inbred strains of rats: the results suggest that each strain can be differentiated phenotypically according to these behavioral responses. Brown Norway rats demonstrated the greatest locomotion during acclimation sessions. Low doses of apomorphine (0.1 and 0.32mg/kg) produced a flat body posture in Lewis animals. A higher dose of apomorphine (1.0mg/kg) markedly increased locomotion in Fisher rats. Buffalo animals showed licking during control sessions and the greatest increase in gnawing at higher doses of apomorphine. DA rats were less responsive than the other strains of apomorphine. Between-strains autoradiographic determination of dopamine receptor densities revealed several differences in D1 receptors labeled by (3)H-SCH 23390 and D2/D3 receptors labeled by (125)I-NCQ 298 in the caudate-putamen and nucleus accumbens. However, the heterogeneity of dopamine receptor densities was not sufficient to explain the strain-specific behavioral responses. These experiments demonstrate variations in behavioral and neurochemical characteristics of inbred strains of rats which could be used to model genetically determined differences in dopamine-mediated behavioral responses.     

Epidemiology of sexually transmitted diseases among pregnant adolescents

Objective: The purpose of this study was to determine the epidemiology of sexually transmitted diseases (STDs) among pregnant adolescents.Methods: Charts of all patients (n = 735) who attended the Maternal and Infant Care Clinic at University Hospital, Newark, NJ, between July 1, 1991, and June 30, 1992, were reviewed for STDs which included gonorrhea, chlamydia, syphilis, and human immunodeficiency virus (HIV). At the first prenatal visit, each registrant had endocervical specimens obtained to detect gonorrhea and chlamydia. A serum sample was obtained for syphilis screening. HIV testing was made available to all patients and testing was done on a voluntary basis. The same STD screening that was done at the initial visit was repeated at 28 and 36 weeks.Results: Twenty-five percent of patients tested positive for one or more STDs. The mean patient age was 17.3 years. The mean gestational age at first visit was 19.5 weeks. The mean number of visits was 7.3. The following STDs were identified: 4.8% of patients tested positive for gonorrhea, 20.9% tested positive for chlamydia, and 1.7% tested positive for syphilis. Twenty-one percent of patients had a positive STD diagnosed at the initial visit. Another 4.8% of patients had an STD diagnosed at some time after the initial visit when the initial screen was negative for STDs. An additional 1% of patients who initially tested positive for an STD had subsequent screening which revealed another STD (different organism). Seven patients tested HIV positive. Sixty-one percent of patients with STDs agreed to HIV testing. One patient had HIV coexistent with another STD.Conclusions: Pregnant adolescents are at risk for multiple STDs. HIV testing should be offered. STD screening should be repeated in the third trimester in adolescent patients.     

Comparison of air-displacement plethysmography with hydrostatic weighing and bioelectrical impedance analysis for the assessment of body composition in healthy adults

BACKGROUND: Over the past decade, considerable attention has been paid to accurately measuring body composition in diverse populations. Recently, the use of air-displacement plethysmography (AP) was proposed as an accurate, comfortable, and accessible method of body-composition analysis. OBJECTIVE: The purpose of this study was to compare measurements of percentage body fat (%BF) by AP and 2 other established techniques, hydrostatic weighing (HW) and bioelectrical impedance analysis (BIA), in adults. DESIGN: The sample consisted of healthy men (n = 23) and women (n = 24). %BF was measured by AP, HW, and BIA. RESULTS: In the total group, %BF(AP) (25.0+/-8.9%) was not significantly different from %BF(HW) (25.1+/-7.7%) or %BF(BIA) (23.9+/-7.7%), and %BF(AP) was significantly correlated with %BF(HW) (r = 0.944, P < 0.001) and with %BF(BIA) (r = 0.859, P < 0.01). Compared with HW, AP underestimated %BF in men (by -1.24+/-3.12%) but overestimated %BF in women (by 1.02+/-2.48%), indicating a significant sex effect (P < 0.05). The differences in estimation between AP and BIA and between BIA and HW were not significantly different between the sexes. CONCLUSION: AP is an accurate method for assessing body composition in healthy adults. Future studies should assess further the cause of the individual variations with this new method.     

Error-related processing during a period of extended wakefulness

The nature of error detection as manifested by the error-related negativity was examined in both a Sternberg memory search task and a visual search task. Both tasks were performed in conditions with consistent or varied stimulus-response mapping and loads of three or six letters. After subjects were trained extensively in all conditions, they performed the tasks throughout the night without sleeping. The data suggest that the effectiveness of error detection decreases over time because of a decrease in the quality of perceptual processing. Error detection also suffers when performance requires more search-related resources. In both cases, the representation of the correct response is compromised. These results indicate that error detection depends on the same perceptual and cognitive processes that are required for correct performance.     

The splay angle: A new measure for assessing neuromuscular dysfunction in rats

This report describes a new method, the splay angle measures, to determine neuromuscular dysfunction. Splay angles are measured from a standard splay test and define hind limb orientation quantified, in degrees, by the paw strike of the hind limbs. We used mutant rats, presenting with a chronic central nervous system demyelinating disease, characterized by tremor, ataxia, immobility, epilepsy, and paralysis (taiep). Significant differences between taiep (n = 12) and normal control rats (n = 10) were found for Linear Splay, AngleLeft, AngleRight, and AngleBoth. These results suggest that the splay angles are a sensitive measure of hind limb orientation and may reflect an underlying pathology.     

A simplified technique for laparoscopic jejunostomy and gastrostomy tube placement

BACKGROUND: Percutaneous endoscopic gastrostomy and jejunostomy tube placement have long been considered the standard for supplying enteral nutrition when oral intake is not possible. Both have well-documented roles and limitations and are associated with a higher than generally appreciated incidence of aspiration. A distally placed tube in the jejunum decreases the chance of this morbid complication. Additionally, when percutaneous endoscopic gastrostomy is indicated but cannot be done for technical reasons, a minimally invasive alternative is desirable. METHODS: In prior series, the techniques suggested for laparoscopic enteral access have characteristics that are either difficult for the average surgeon to duplicate, or use nonstandard anchoring techniques of the bowel to the abdominal wall. A simple, laparoscopically directed, percutaneous technique utilizing cost-effective appliances is described, and suggested indications are outlined. RESULTS: This technique has been successfully applied in 46 patients with minimal complications. CONCLUSIONS: A simplified technique for laparoscopic jejunostomy and gastrostomy tube placement is described. This has been successfully deployed in 46 patients with minimal morbidity. The procedure lessens the need for sophisticated suturing skills and duplicates standard small bowel to abdominal wall fixation methods.     

Metastasis of hepatocellular carcinoma to the right colon manifested by gastrointestinal bleeding

An 82-year-old black woman with a history of hepatocellular carcinoma presented with gastrointestinal bleeding. Barium enema and fibrocolonoscopy revealed a 4-cm polypoid mass at the level of the ascending colon with evidence of active bleeding. Biopsies of the lesion proved it to be metastatic hepatocellular carcinoma. Exploratory laparotomy revealed no further dissemination of the tumor, and the patient underwent an ileocolectomy. The serosal side of the colonic lesion was free from tumor, and there was no peritoneal implantation, direct extension, or lymph node involvement. This case represents an extremely rare presentation of metastatic hepatocellular carcinoma.