Glutathione conjugation with 1-chloro-2,4-dinitrobenzene (CDNB): interindividual variability in human liver, lung, kidney and intestine

The rate of glutathione conjugation with 1-chloro-2,4-dinitrobenzene (CDNB) was measured in specimens of human liver (n = 93), sigmoid colon (n = 56), renal cortex (n = 67) and lung (n = 68). In the liver there was a weak but significant (r = - 0.247 p = 0.017) negative correlation between the activity of glutathione transferase and the liver donor's age. Such a correlation was not found in the renal cortex, lung and colon. In the renal cortex and in lung the rate of glutathione conjugation with CDNB was a little but significantly (p < 0.05) higher in women than men, whereas no sex-dependent difference was observed in the liver and colon. The distribution of glutathione transferase activity was polymorphic in the mucosa of colon and renal cortex of men but not in that of women. Smoking seems not to affect the glutathione conjugation rate with CDNB in lung. The activity of glutathione transferase was 2-, 6-, and 7-fold greater in liver than in the renal cortex, lung and colon, respectively. There was a large interindividual variability of the hepatic glutathione transferase activity, and because this variability, 15% of the population studied catalyzed the glutathione conjugation with CDNB at a rate similar to those of the renal cortex and duodenum. The subjects with low expression of the hepatic glutathione transferase should be more exposed to the effects of toxic and carcinogenic compounds.     

Radioiodine therapy for hyperthyroidism in young patients--perception of risk and use

In the radiation treatment of inclined lesions the longitudinal axis of beam should be always parallel to the longitudinal axis of lesion in the treatment plane. Hence the choice of correct collimator angle is of prime importance in the oblique field off-axis treatment planning of inclined lesions. In this paper a graphical method is discussed to determine the collimator angles from the CT scans taken at different off-axis planes. A phantom was constructed which can simulate conditions like inclined lesion in the patient and CT scans were taken at different levels. The collimator angles estimated from CT scans are found to match with the collimator angles obtained from simulator within +/- 1 degree for various gantry angles. The method is applied to plan a case of cancer of the oesophagus (upper third), which is a typical example of inclined lesion.     

Diabetes-induced endothelial dysfunction is prevented by long-term treatment with the modified iron chelator, hydroxyethyl starch conjugated-deferoxamine

Oxygen radicals are believed to play a role in vascular complications of diabetes mellitus. In this study, we evaluated whether long-term treatment with an iron chelator and inhibitor of metal-catalyzed hydroxyl radicals (.OH) could prevent diabetes-induced defects in endothelium-dependent relaxation. Diabetes was induced in Sprague-Dawley rats by injection of streptozotocin. At 48 h after streptozotocin, a subgroup of diabetic rats received daily injections of 50 mg/kg hydroxyethyl starch conjugated-deferoxamine (HES-DFO) for a total of 8 weeks. Long-term treatment with HES-DFO did not modify serum insulin or blood glucose taken at the end of the study; however, a modest reduction in glycosylated hemoglobin was present. In precontracted aortic rings suspended in tissue baths, endothelium-dependent relaxation to acetylcholine was impaired in diabetic rings compared with control rings in the presence or absence of indomethacin. Endothelium-independent relaxation to nitroglycerin was unaltered. Long-term treatment with HES-DFO had no effect on relaxation to nitroglycerin but completely prevented the impaired relaxation to acetylcholine in diabetic rings in either the presence or absence of indomethacin. These data suggest that iron-catalyzed .OH formation contributes to the development of diabetes-associated endothelial dysfunction.     

Morphological changes in the jejunum of calves naturally infected with Giardia spp. and Cryptosporidium spp

Giardiosis and cryptosporidiosis are frequently diagnosed in calves at the large animal clinic of the veterinary school. Few studies have been reported in the literature regarding pathogenesis of these two intestinal protozoa. The aims of this study were to follow the histological changes in the villi and crypts and the changes in the number of intraepithelial lymphocytes in the jejunum of naturally infected calves during the acute phase of infection. For this purpose, 29 calves aged between 7 and 10 days were bought at a local auction. The animals were housed in individual pens to avoid cross-contamination. Fecal samples were examined microscopically for the presence of Giardia cysts and Cryptosporidium oocysts, three times per week for a period of 45 days. Six calves did not pass any cysts or oocysts and were used as controls. Fifteen calves passed Giardia cysts only, five passed both cysts and oocysts, and three passed oocysts only. The villus to crypt ratio index was 1.76 in the control group and 1.08 in the Giardia-infected group. In the Cryptosporidium-infected calves, the ratio was 1.18 and calves infected with both parasites had an index of 1.37. The number of intraepithelial lymphocytes per millimeter of jejunum tissue was 21 in the control group. This number was doubled in the calves infected with Giardia, but was slightly lower in the other infected groups. All of the infected calves had intermittent diarrhea and mucus was seen in many fecal samples.     

Embolization of the nidus of brain arteriovenous malformations with n-butyl cyanoacrylate

OBJECTIVE: To demonstrate that nidus embolization of brain arteriovenous malformations (AVMs) with Histoacryl (B. Braun, Melsungen, Germany) is effective and yields low morbidity and mortality rates. METHODS: We present a retrospective analysis of 54 brain AVMs treated at the University of Illinois at Chicago from April 1994 to December 1995. Treatment modalities included embolization in all cases and then surgical resection or radiosurgery. INSTRUMENTATION: The nidus was reached with the combined use of a Magic microcatheter (Balt, Montmorency, France) and a Terumo 0.010-inch guidewire. TECHNIQUE: Embolization was performed only when the tip of the microcatheter was wedged into the nidus of the AVMs with no reflux of contrast proximally. The embolization was performed using simultaneous biplane roadmapping with the patient under general anesthesia without Amytal testing. RESULTS: Twenty-six of 54 patients are still waiting for more radical treatment. Two deaths and two minor and one severe permanent neurological deficit occurred. Three patients were cured with embolization alone; 11 patients were cured after surgical resection. Three patients underwent radiosurgery, with one cure after 1 year. CONCLUSION: Nidus embolization with Histoacryl is an effective technique that permits complete cure of a large number of brain AVMs, with or without surgical resection and/or radiosurgery.     

Electroconvulsive therapy for treatment of intractable seizures. Initial findings in two children

We treated two children with intractable epilepsy with electroconvulsive therapy (ECT) for seizure control. One child showed a change in seizure pattern with treatment, which at greater intensity was also effective in stopping nonconvulsive status epilepticus. The other child showed a decrease in spontaneous seizure frequency during short-term treatment. These findings suggest a possible role for ECT in the management of intractable epilepsy in children who are not candidates for epileptic surgery.     

Erosive pustular dermatosis of the scalp in skin grafts: report of three cases

The objective of the present prospective, noncomparative, multicenter study was assess the safety and efficacy of gentamicin and doxycycline therapy for human brucellosis. In the first part of the study, a cohort of 17 patients received 100 mg of doxycycline (or 50 mg/kg of body weight per day if the body weight was < 40 kg) orally every 12 h for 45 days (cohort 1). In the second part of the study a subsequent cohort of 35 patients was treated with doxycycline at the same dosage for 30 days (cohort 2). All patients were treated intramuscularly with gentamicin at 240 mg (or 5 mg/kg per day if the body weight was < 50 kg) once daily for the first 7 days. Both cohorts showed a favorable response during therapy, and there were no therapeutic failures. Relapse was noted in 1 (5.9%; 95% confidence interval [95% CI], 0.15 to 28.7%) of the 17 patients in cohort 1 and in 8 (22.9%; 95% CI, 10.4 to 40.1%) of the 35 patients in cohort 2. Nineteen patients (36.5%; 95% CI, 23.6 to 51.0%) had adverse effects, with no differences between cohorts, and no patients had a treatment-limiting adverse effect. The study indicates that the combination of doxycycline for 45 days and gentamicin for 7 days is an effective and well-tolerated therapy for human brucellosis. The relapse rates obtained with doxycycline treatment for 30 days appear to be higher than those obtained with doxycycline treatment for 45 days.     

Variation in hippocampal neuron number with age and brain volume

Hippocampal size and neuron number are reduced in a number of conditions, including temporal lobe epilepsy and Alzheimer's disease. Furthermore, a decrease with advancing age has also been suggested. The present study examined the entire hippocampal formation of 12 subjects aged from 46 to 85 years and free from neurological disease. The volume of seven subregions (CA1, CA2-3, CA4, dentate gyrus, subiculum, presubiculum and white matter) was determined and the number of neurons estimated in each of these grey matter subregions using the optical dissector technique. There was a significant relationship between CA1 neuron number and cerebrum volume. Multivariate analysis showed the greater contribution to the variance in CA1 neuron number was made by cerebrum volume (69%) rather than age (2%) or sex (1%). The findings of this study show that, in neurologically normal individuals, brain size is a major determinant of the number of CA1 neurons.     

Age-dependent Neisseria meningitidis serogroup C class-specific antibody concentrations and bactericidal titers in sera from young children from Montana immunized with a licensed polysaccharide vaccine

Neisseria meningitidis serogroup C bactericidal titers and class-specific enzyme-linked immunosorbent assay (ELISA) antibody concentrations were measured in sera from 173 children (1 to 5 years old) before and 6 weeks and 7 months following vaccination with a quadrivalent (A/C/Y/W-135) polysaccharide vaccine. The immune responses of the children were compared with those of 40 adults 6 weeks postvaccination. Both bactericidal titers and ELISA antibody concentrations were significantly higher in the adults than in the children (P < 0.05). In addition, the ratio of immunoglobulin G (IgG) to IgM was higher in the children than in the adults. With an ELISA total antibody concentration of >/=2 microg/ml used as a measure of seroconversion, >/=84% of the individuals from each age group responded to the serogroup C polysaccharide. However, with a >/=4-fold-increase in bactericidal titer used, only 18% of 1-year-olds, 32% of 2-year-olds, and 50 to 60% of 3-, 4-, and 5-year-olds seroconverted. The ELISA results suggest that >50% of all children retained >/=2 microg of total antibody per ml at 7 months postimmunization. However, the bactericidal titers suggest that <10% of children <4 years old retained a >/=4-fold increase at 7 months following vaccination. Of particular note, 59 of 79 sera (75%) from the 1- and 2-year-olds had high ELISA antibody concentrations (2 to 20 microg/ml) with no associated bactericidal titer (<1:8). Discordant results between bactericidal titers and ELISA antibody concentrations were not explained by the presence of IgA blocking antibody or relative levels of IgG and IgM. The bactericidal results show age-dependent differences in the production and retention of antibody in young children immunized with serogroup C polysaccharide; these differences are not evident with the ELISA data.