Systemic effects of intraocular epinephrine during cataract surgery

This paper examines the effects of intraocular epinephrine on systemic blood pressure and heart rate during cataract surgery. Sixty-two patients were studied, all of whom received an intraocular infusion of approximately 200 to 300 mL of balanced salt solution with 0.5 mL of epinephrine 1:1000. There was no statistically significant change in blood pressure or heart rate during the time of epinephrine administration. Electrocardiogram monitoring during surgery showed no changes. We believe that dilute concentrations of epinephrine administered during extracapsular cataract extraction pose little threat of systemic toxicity.     

Chronic parasite infection in mice induces brain granulomas and differentially alters brain nerve growth factor levels and thermal responses in paws

Schistosoma mansoni infection, both in humans and in animal models, is known to induce granulomas in the liver and intestine. It has also been reported that in humans the eggs of this parasite can reach the brain, causing psychiatric and neuropathological disorders. Whether this also occurs in rodents is unknown. To answer this question, mice were infected with this parasite and the central nervous system (CNS) examined at various time intervals. The results show that schistosomiasis induced granulomas in several regions of the CNS and increased nerve growth factor (NGF) levels in the cortex, hypothalamus and brain stem, but not in the hippocampus. The infection also caused paw hyperalgesia, as determined by the hot-plate test, and a local increase in NGF, but not in substance P. These findings indicate that the murine model of infection can be used for studying mechanisms leading to human neuroschistosomiasis and suggest that the neuropathological disorders and the sensory deficits observed in human schistosomiasis are associated with impaired levels of NGF in the peripheral and central nervous system. Received: 18 January 1996 / Revised, accepted: 16 April 1996     

Multiple penile horns: case report and review

We report a case of unusually large multiple penile horns following removal of condylomata acuminata. Penile horns can grow rapidly, although malignant degeneration is uncommon. Wide excision with deep biopsy of skin at the base of the lesion probably is appropriate treatment.     

High and low frequency transcutaneous electrical nerve stimulation inhibits nociceptive responses induced by CO2 laser stimulation in humans

The aim of the study was to evaluate the effects of transcutaneous electric nerve stimulation (TENS) on CO(2) laser evoked potentials (LEPs) in 16 normal subjects. The volar side of the forearm was stimulated by 10 Hz TENS in eight subjects and by 100 Hz TENS in the remainder; the skin of the forearm was stimulated by CO(2) laser and the LEPs were recorded in basal conditions and soon after and 15 min after TENS. Both low and high frequency TENS significantly reduced the subjective rating of heat stimuli and the LEPs amplitude, although high frequency TENS appeared more efficacious. TENS seemed to exert a mild inhibition of the perception and processing of pain induced by laser Adelta fibres activation; the implications of these effects in the clinical employment of TENS remain to be clarified.     

Operant conditioning studies of taste discrimination in the pigeon (Columba livia)

In the conditioning procedure employed in this study, pigeons were trained to dip their bills into a container and then to peck either at a left or at a right key, depending on whether the container was full of distilled water or of a solution of the substance being tested. The discrimination thresholds found (from one bird each) were 2 g/l (0.034 M) for NaCl, 2 g/l (0.024 M) for NaHCO₃, 1 g/l (0.013 M) for KCl, 0.5 g/l (0.005 M) for KHCO₃. Following the same procedure, two birds were then faced with the choice between the solution of the known substance and of a novel one. A higher degree of discrimination was found between NaHCO₃ and KHCO₃ than between NaHCO₃ and NaCl; in the latter case, choices appeared to be mostly based on the concentration of the two substances.     

Morphometric and histological evaluation of uterine leiomyomas treated with GnRH agonists or progestational agents

Both gonadotropin-releasing hormone (GnRH agonists) and progestational agents are commonly used in order to reduce the size of uterine leiomyomas before surgery. So far, little is known about the histologic changes underlying such shrinkage mechanism. Probably the conflicting data on this subject are due to the qualitative and subjective methods used by most previous reports. In this study we analyzed 42 leiomyomas from patients treated with GnRH agonists (14 different patient samples), patients treated with progestational agents (14 different patient samples) and age-matched control patients (14 different patient samples), using qualitative (light microscope analysis) and quantitative (morphometric analysis by a specific software) methods. We assessed the following parameters: areas of necrosis, areas of hyalinization, vasal density, vasal thrombi, thickness of vasal walls, size of vasal lumina, cell density, maximum nuclear diameter, maximum cytoplasmic diameter, mitotic index on each sample. The analysis showed that leiomyomas from women treated with GnRH agonist exhibited broader areas of necrosis, greater cell density, and wider vasal lumina, while those from women treated with progestational agents exhibited thicker vasal walls than the other two groups, respectively. In conclusion, our results suggest that vasal wall changes are the basis of leiomyomas shrinkage after GnRH agonist therapy.