Free radicals antioxidant enzymes and lipid peroxidation in different types of leukemias

Free radicals are highly reactive species that have been implicated in the pathogenesis of many diseases. Reactive oxygen species can initiate lipid peroxidation and DNA damage leading to mutagenesis, carcinogenesis and cell death, if the antioxidant system is impaired. This study was undertaken to examine the prevalence of oxidative stress and the role of antioxidant defence in untreated leukemia patients. The generation of superoxide anion and hydrogen peroxide by leukocytes, plasma malondialdehyde levels, red cell copper zinc superoxide dismutase (Cu-Zn SOD) and glutathione peroxidase (GSH-PX) activities were determined in 30 patients with different types of leukemias prior to therapy. The superoxide anion generation by polymorphonuclear leukocytes was found to be significantly increased in leukemia patients especially those with acute lymphocytic and nonlymphocytic leukemias, while the hydrogen peroxide levels were comparable to the control values. Plasma lipid peroxidation products in untreated leukemia patients were in the normal range. Red cell Cu-Zn SOD and GSH-PX activities were significantly increased and showed no correlation with the hemoglobin content. Although superoxide generation was high, lipid peroxide levels were normal in these patients. This might be due to the increased activities of the antioxidant enzymes (SOD, GSH-PX) which counteract lipid peroxidation. Increased free radical generation, especially superoxide anion in leukemia patients and increased antioxidant defence enzymes, which is an adaptive protective response, are indicative of mild oxidative stress. There were no significant differences for the parameters cited above between different types of leukemias, suggesting that the changes are not specific to the type of leukemia.     

Longitudinal outcome with pharmacotherapy in a naturalistic study of panic disorder

BACKGROUND: Current recommendations suggest that pharmacotherapy for patients with panic disorder should be continued for at least 1 year [Am. J. Psychiatry 155 (1998) 1], despite a paucity of data systematically examining outcome for periods greater than 3-6 months. It is critically important to obtain more information on the effectiveness of medications over time for patients who initially responded to pharmacotherapy for panic disorder. METHODS: Long-term outcome was examined for 78 patients who attained a 2-month period of sustained remission on medication and received maintenance pharmacotherapy for up to 24 months during the Massachusetts General Hospital Longitudinal Study of Panic Disorder, a prospective, naturalistic study. Participants were categorized by their maintenance treatment condition at remission: benzodiazepine alone (N = 45, 58%), antidepressant alone (N = 12, 16%), and combined treatment with a benzodiazepine and an antidepressant (N = 21, 27%). RESULTS: Approximately half (N = 36, 46%) of the patients who had achieved remission relapsed at some time over the 2-year naturalistic study period, despite continued and adequate pharmacotherapy. There was no difference in timing or frequency of relapse by type of maintenance pharmacotherapy. LIMITATIONS: Interpretation of the data is limited by the naturalistic nature of the study, and by the relatively low sample size.CONCLUSIONS: This data suggests that patients with panic disorder have a high rate of relapse even after acute response to pharmacotherapy, despite continued treatment. In addition, the use of combined pharmacotherapy with antidepressants and benzodiazepines does not appear to provide greater protection from relapse than monotherapy.     

Oral lesions among persons with HIV disease with and without highly active antiretroviral therapy in southern India

BACKGROUND: The advent of highly active antiretroviral therapy (HAART) has changed the scenario of human immunodeficiency virus (HIV) infection. HIV patients in India have now access to generic HAART and this is the first report describing oral lesions in patients on HAART from our country. METHODS: Oral lesions were studied in HIV seropositive patients (n = 50 on HAART and n = 50 not on HAART) attending a tertiary HIV referral care centre in India and patients on HAART were followed up. RESULTS: There was a difference in the occurrence of oral candidiasis (OC) between HAART and non-HAART participants (8%, 24%; P < 0.05). Pseudomembranous candidiasis was 4% and 18% in HAART and non-HAART groups respectively (P < 0.05). In patients with CD4 count 200, pigmentation was 43.8% in the HAART group and 14.8% in the non-HAART group (P < 0.05). CONCLUSION: The prevalence of OC in patients who had access to HAART was less when compared with those who did not have access to HAART.     

Effect of mechanical trauma on the tooth germ of rat molar--a scanning electron microscope study.

OBJECTIVE: Clinical and histopathological evaluation of mechanical trauma on the development of maxillary first molar with Scanning Electron Microscope. DESIGN: Experimental study with four newborn Wistar rats. Trauma induced on 1st, 3rd, 7th and 10th postnatal days with dental K file. Right first molar region of the maxilla was the experimental side and the left side as control. Animals were sacrificed on the 42nd Postnatal day when the teeth came into functional occlusion. Teeth were evaluated clinically and SEM study of the crown was performed. RESULTS: Marked disfigurement of cusps, roughened defective, enamel, crown dilacerations and enamel hypoplasia were observed. Damage was less severe to the tooth subjected to trauma on the 10th postnatal day.     

Cytotoxicity of some indium radiopharmaceuticals in mouse testes

The biological effects of [111In]oxine, [111In]citrate, and [114mIn]citrate localized in mouse testes as well as the effects of external x-rays are investigated. The in vivo radiotoxicity of [111In] oxine is far greater than the chemotoxicity of oxine. Of these radiolabeled compounds, [111In] oxine is the most effective in reducing the sperm-head population, the mean lethal dose (D37) to the organ being about 0.16 Gy at 37% survival of the sperm heads. The corresponding values of D37 for [111In]citrate, [114mIn]citrate and x-rays are approximately 0.34, 0.57, and 0.67 Gy, respectively. The present results affirm our earlier finding of the inadequacy of conventional dosimetry in estimating the biologic consequences of Auger-electron emitters in vivo. The very different radiotoxicities of [111In]oxine and [111In]citrate draw attention to the role of the chemical nature of the radiolabeled compounds in the expression of biologic effects in vivo, an aspect that is not considered explicitly in the formulation of conventional dosimetry.