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Photoinduced magnetization in a magnet based on organic species is reported for the first time. Upon optical excitation in the blue region of spectrum, Mn(tetracyanoethylene)(x)*y(CH2Cl2) (x approximately 2, y is approximately 0.8) exhibits increased magnetic susceptibility at temperatures as high as 75 K, accompanied with photoinduced absorption in the visible and infrared spectral regions. These effects are partially reversible by lower energy visible light and fully reversible by thermal treatment. The results suggest trapping of the photoexcited charge in a metastable state with enhanced exchange interaction.

Sputum samples from AIDS patients with and without pulmonary tuberculosis were analyzed morphologically and immunocytochemically to determine the frequency of occurrence of Candida sp. Mycobacterial infection was detected by bacterioscopy and/or culture and cytological evaluation was performed using Papanicolaou and Toluidine Blue staining. Immunoreaction for Candida sp was performed using polyclonal antibody in selected cases with fungal structures in smears stained by the Papanicolaou or Toluidine Blue method. An increased frequency of Candida sp (2.5 times) was observed in the tuberculous group compared to the group of AIDS patients without tuberculosis. The Toluidine Blue stain showed good results for the detection of Candida sp in sputum. Due to the increased risk of this opportunistic infection among more severely immunocompromised patients. Toluidine Blue staining of sputum samples submitted to analysis seems to be a reliable screening method.

Three members of a family with a hereditary neuropathy were studied. Light, electron microscopy and teasing of isolated fibres were performed. The findings confirmed the clinical and electrophysiological hypothesis of hypertrophic form of Charcot-Marie-Tooth disease. Hypertrophy of Schwann cells with the formation of onion bulb figures as the most evident ultrastructural feature, besides demyelination, remyelination and mild axonal degeneration. Recent data about the genetic transmission and pathogenesis of the hereditary motor and sensory neuropathies (HMSN) are discussed.

Results of investigation about Enterovirus-70 (EV-70) as an etiologic agent of epidemic of acute haemorrhagic conjunctivitis (AHC) and neurological disease in the metropolitan area of São Paulo city are presented. During the first three months of 1984, in an epidemic period of AHC, 3 groups with a total of 291 persons were studied. The group A included 90 individuals affected by AHC; the 99 persons belonging to group B did not acquire the AHC but referred familiar contact with the ill individuals; the group C included 102 persons who denied the AHC or any contact with the illness. Neutralization test in BHK-21 cell culture was used for measurement of antibodies in sera. For the detection of the presence of IgM, indirect immunofluorescence assay was utilized. The presence of IgM antibodies was observed in 56.7%, 33.3% and 20.6% of persons belonging to groups A, B and C, respectively. The 10-29 age group was the most affected in the group A. From april 1984, after the end of epidemic period of AHC, until December 1987, three sporadic cases of AHC and 10 cases with acute neurological disease associated with recent infection by EV-70 were observed. Nine of 10 persons with acute neurological symptoms had paralysis of cranial nerves, all of them recovering without sequelae. The circulation of EV-70 in the population during the endemic period was maintained by either asymptomatic, sporadic cases of AHC or neurological diseases.