Participation of angiotensin II in learning and memory. III. Interactions of angiotensin II with GABAergic drugs

The experiments were carried out on male albino rats trained and tested for retention (24 hr later) in a shuttle-box. Angiotensin II (AT II) 0.10 micrograms intracerebroventricularly (i.c.v.), gamma-aminobutyric acid (GABA) 100 micrograms i.c.v., bicuculline 0.5 and 1.0 mg/kg intraperitoneally (i.p.), and picrotoxin 0.5 and 1.0 mg/kg i.p. administered independently or in combinations immediately after training. AT II was found to improve retention. GABA also facilitated retention. Combination of AT II + GABA potentiated the memory-improving effect of AT II. Bicuculline and picrotoxin at a dose of 0.5 mg/kg did not affect retention, while at a dose of 1.0 mg/kg they improved it. Combinations of AT II + bicuculline (0.5 mg/kg) and AT II + picrotoxin (0.5 mg/kg) abolished the retention-improving effect of AT II. Bicuculline (0.5 mg/kg) or picrotoxin (0.5 mg/kg) abolished the retention-facilitating effect of the combination of AT II + GABA as well as the potentiating action of GABA on the memory effect of AT II. These results suggest the participation of GABAergic transmission in the CNS in the mechanisms of the long-term memory-improving effect of AT II.     

Effects of growth hormone on glucose and fat metabolism in human subjects.

This article focuses on in vivo data from tests performed in normal subjects and in patients who had abnormal growth hormone (GH) status. Experimental data in human subjects demonstrate that GH acutely inhibits glucose disposal in skeletal muscle. At the same time GH stimulates the turnover and oxidation of free fatty acid (FFA), and experimental evidence suggests a causal link between elevated FFA levels and insulin resistance in skeletal muscle. Observational data in GH-deficient adults do not indicate that GH replacement is associated with significant impairment of glucose tolerance, but it is recommended that overdosing be avoided and glycemic control be monitored.     

Combined use of cryotherapy and diode laser photocoagulation for the treatment of threshold retinopathy of prematurity.

PURPOSE: Cryotherapy and indirect laser retinal photoablation are both effective in the treatment of retinopathy of prematurity (ROP). We describe the safety, efficiency, and effectiveness of combined cryotherapy and diode laser photocoagulation to treat threshold ROP. METHODS: Records of patients developing threshold ROP from January 1, 1996 through December 31, 1998, were retrospectively reviewed to identify those treated with combined cryotherapy and photocoagulation and followed up for at least 45 days postoperatively. Diode laser was used to ablate posterior avascular retina, and cryotherapy was used for anterior retina. Data reviewed included ocular and systemic complication rates, treatment duration, number of laser burns, most recent fundus examination, visual acuity, and refraction. RESULTS: In 13 patients, 23 eyes received combined treatment. No intraoperative complications occurred. Mean duration of anesthesia and treatment was 35 +/- 8 minutes/eye. A mean of 117 +/- 84 laser burns/eye were applied. In 20 of 23 eyes (87.0%), anatomic outcome was favorable at last examination. In 13 of 16 eyes (81.3%), functional (visual acuity) outcome was favorable (visual acuity better than 20/200) at 1 year. At 6 months or later, 14 of 16 eyes (87.5%) measured were myopic, of which 5 (31.3%) were highly myopic (> 6 diopters). CONCLUSIONS: The effectiveness of treating ROP with combined cryotherapy and diode laser photocoagulation compares with that of either modality alone. By decreasing the number of laser applications, combined therapy may be faster and technically easier for eyes with very posterior ROP. This may decrease the number of complications seen when either excessive cryotherapy or laser retinal photoablation is used.     

Migratory, invasive and metastatic capacity of NCAM transfected rat glioma cells

A cDNA encoding a transmembrane 140 kDa isoform of the neural cell adhesion molecule, NCAM, was transfected into the rat glioma cell line BT4Cn. Transfectants with a homogeneously high expression of NCAM-B showed a decreased capacity for penetration of an artificial basement membrane when compared to cells transfected with expression-vector alone or untransfected cells. However, when injected subcutaneously into nude mice, both NCAM expressing cells and control cells produced invasive tumors. Nude mice injected with NCAM positive cells developed tumors with slower growth rates as compared to those induced by NCAM negative cells. This implies that NCAM may not only be involved in adhesive and motile behaviour of glioma cells, but also in their growth regulation.     

Epidemiologie und Prävention von AIDS in der Bevölkerung

International Journal of Public Health - Die Übertragungswege des HIV, welche in der Bevölkerung eine Rolle spielen, sind heute bekannt. Neben der sexuellen Übertragung, der...     

Wear of the Christiansen hip prosthesis

The wear was examined in 39 Christiansen total hip prostheses, which were removed because of mechanical loosening after being used 5 (3-11) years. In the polyacetal acetabular cups, the head had made an eccentric defect, the mean volume of which was 680 (180-3310) mm³. The mean penetration of the head into the wall of the cup was 0.8 (0.1-3.2) mm. In two additional cups the head had penetrated right through the wall of the cup. In three prostheses the polyacetal sleeve of the trunnion was so worn that the head bore directly on the stem. There was a positive correlation between wear and the time the prostheses had been used before symptoms of loosening presented.