Genesis of neurons of the retinal ganglion cell layer in the opossum

Summary In this study, we have examined the genesis of neurons of the retinal ganglion cell layer of the opossum Didelphis marsupialis by [³H]-thymidine autoradiography. Our results suggest that most neurons surviving to adulthood are generated in postnatal life from day 1 to day 23. Cells are generated according to a coarse gradient from the retinal geometric center to the periphery. Regional analysis of soma size distributions in different cohorts suggest that this gradient is actually formed by two partially-overlapping, concentric waves of cell proliferation. Most medium and large ganglion cells are formed during the early wave, whereas most displaced amacrine cells and small ganglion cells are formed during the late wave. Our results confirm the appropriateness of the opossum as a model for studies of development of the mammalian visual system.     

Incidence of psychiatric side effects during pegylated interferon- alpha retreatment in nonresponder hepatitis C virus-infected patients.

Objective: Evaluate the incidence of mental disorders using pegylated interferon plus ribavirin retreatment in nonresponder hepatitis C virus‐infected patients. Method: The Mini‐International Neuropsychiatric Interview (MINI) was used to evaluate 30 hepatitis C virus‐infected interferon‐nonresponder patients at baseline and following 4, 12 and 24 weeks of pegylated interferon retreatment. Results: During the pegylated interferon/ribavirin retreatment, 5(16.6%) patients developed psychiatric side effects: 3(10%) were diagnosed with major depressive disorder, 1(3.3%) had a brief psychotic disorder and 1(3.3%) presented with panic attacks. Conclusion: This is the first prospective study evaluating the incidence of neuropsychiatric side effects during interferon retreatment of hepatitis C virus‐infected patients, suggesting that the risk of acquiring serious psychiatric symptoms during retreatment with interferon‐α (IFN‐α) may not be higher than during the first antiviral therapy. This finding challenges the hypothesis that during a second treatment with IFN‐α, patients with hepatitis C may be at greater risk for neuropsychiatric side effects than naïve patients.     

Behavior associated with HIV and HCV infection in female prison inmates in São Paulo, Brazil

An increase has been observed in AIDS and hepatitis C cases in women, including female prison inmates. This study focused on inmates' behavioral factors associated with risk of HIV and HCV transmission in a women's detention facility in S?o Paulo, Brazil. Behavioral questionnaires were applied and HIV and HCV serology were performed. The selected measure of association was odds ratio for both the bi and multivariate logistic regression analyses. 290 inmates participated in the study. HIV and HCV prevalence rates were 13.9% and 16.2%, respectively. Statistically significant associations were observed (p < 0.05) between HIV and the following variables: partner with AIDS OR = 6.9 (2.7-35.2); injection drug users (IDU) OR = 3.3 (1.6-14.7); regular partner OR = 3.7 (1.5-8.3), and between HCV and: IDU OR = 13.7 (4.4-42.7); IDU partner OR = 4.9 (1.9-12.2); previous arrest OR = 2.8 (1.2-6.5) adjusted for: partner with AIDS, IDU, IDU partner, drug user, and previous arrest. In conclusion, parenteral risk was associated with HIV and HCV infection and sexual risk with HIV. Appropriate and continuous preventive programs are recommended in the prison.     

Anti-tuberculosis drug resistance in Portugal.

SETTING: A survey based upon a representative sample of smear-positive pulmonary tuberculosis patients was undertaken in Portugal, as part of the World Health Organization's Global Project on Anti-Tuberculosis Drug Resistance Surveillance. OBJECTIVE: To determine the level of primary antituberculosis drug resistance at both national and regional levels, and to assess its relative weight within the performance of the National Tuberculosis Programme (NTP). DESIGN: Mycobacterium tuberculosis isolates from 1,105 patients with smear-positive pulmonary tuberculosis admitted to 46 randomly stratified treatment centres all over mainland Portugal were submitted to susceptibility testing with four drugs. Human immunodeficiency virus (HIV) testing was included in the patients' evaluation scheme. RESULTS: Of the strains isolated, 197 (17.8%) were resistant to at least one drug. Primary resistance to isoniazid was 7.7% and to rifampicin 1.9%. Acquired drug resistance was 39.2% in total, any acquired resistance to isoniazid 31.1% and to rifampicin 20.9%. Primary multidrug resistance (MDR) was 1.8% and acquired MDR was 20.9%. HIV testing was positive in 29.2% of MDR-TB cases. CONCLUSIONS: Drug resistance in Portugal is high. Primary MDR and particularly acquired MDR occur in a high proportion of cases, indicating a need for improvement in NTP performance.     

Clinical and histopathological features of NASH in workers exposed to chemicals with or without associated metabolic conditions.

BaCKGROUND/AIMS: Non-alcoholic steatohepatitis (NASH) has been associated with exposure to chemicals among workers from an industrial complex in Brazil. We investigated the NASH profile of these individuals associated or not with metabolic conditions. METHODS: Eighty-four patients with NASH were classified into three groups: G1, 31 patients exposed to chemicals (benzene, xylene, vinyl chloride and others); G2, 30 exposed patients who also presented with obesity, hyperlipidemia and diabetes; and G3, 23 non-exposed patients who presented with metabolic conditions. RESULTS: G1 and G2 were similar in terms of gender (97% and 100% males) and age (37+/-5.4 and 39+/-6.5 years). In G3, 74% were males and the age was 48+/-3.4 years (P<0.05). In G2, obesity was present in 26.6%, hyperlipidemia in 66.6% and diabetes in 6.6%. In G3, obesity was observed in 43.4%, hyperlipidemia in 30.4% and diabetes in 26%. Macro- and microsteatosis were observed in 100% of cases. Perisinusoidal fibrosis was observed in 71% patients in G1, 80% in G2 and 52% in G3 (P<0.05). Histological evidence of cholestasis was present in 53% of cases in G1, 50% in G2 and 13% in G3 (P<0.05). CONCLUSIONS: Exposure to chemicals appears to be an independent risk factor for NASH that presents a peculiar profile. It is more frequently seen in men younger than non-exposed ones. Steatosis, fibrosis and cholestasis were frequent histological findings. Co-existing metabolic factors did not seem to influence clinical or histopathological presentation.     

Usefulness of Ictal and Interictal 99mTC Ethyl Cysteinate Dimer Single Photon Emission Computed Tomography in Patients with Refractory Partial Epilepsy

Summary: Purpose: Ictal perfusion single photon emission computed tomography (SPECT), using HMPAO, has been shown to localize epileptic foci in ～90% of studies. Unfortunately, HMPAO decomposes rapidly, precluding the performance of ictal studies. Ethyl cysteinate dimer (ECD) is a SPECT perfusion agent recently approved by the Food and Drug Administration. After preparation, this compound is stable for ～6 h. facilitating the performance of ictal studies. Methods: In a prospective, open-label, uncontrolled, non randomized study, we evaluated the potential benefits of the use of ^99mTc-ECD SPECT for lateralization of the epileptic focus. Ten consecutive adult epilepsy surgery candidates were studied with ictal and interictal ^99mTc-ECD SPECT. Results: The mean delay between seizure onset and ictal SPECT injection was 23.2 s. The mean seizure duration was 84.1 s. Ictal studies agreement between the epilepsy focus and area of hyperperfusion was evident in 8 of 10 cases. In one case, SPECT was lateralized in a patient with bilateral temporal lobe epilepsy (TLE); however, hyperperfusion was observed on the same side of that particular seizure. In another case, there was location disagreement. Interictal SPECT showed focal hypoperfusion in three cases. Conclusions: ^99mTc-ECD proved to be an optimal tracer for ictal studies. Although this is a small series, the results of ictal and interictal findings using 99mTc-ECD are similar to those reported with ^99mTc-HMPA0. Because ^99mTc-ECD has a longer decomposition time, true ictal studies are easier to obtain. This new tracer will probably allow the use of ictal SPECT to become widely accepted in most epilepsy centers.