Gutemberg de Melo Rocha

Cross-reactive IgE antibody responses to tropomyosins from Ascaris lumbricoides and cockroach

BACKGROUND Evidence indicates that infection with Ascaris lumbricoides may promote development of allergy and asthma. OBJECTIVE To study the role of tropomyosin, a pan-allergen in invertebrates, in IgE responses to A lumbricoides. METHODS Recombinant A lumbricoides and Periplaneta americana tropomyosins were expressed in Pichia pastoris. Levels of IgE to tropomyosins from A lumbricoides and P americana were determined by chimeric ELISA in sera from 119 children living in a parasite-endemic area and 112 patients with cockroach allergy from the allergy clinics. Presence of tropomyosin in A lumbricoides larvae at L3 stage was evaluated by immunofluorescence using mAb 1A6, directed against mite tropomyosin. Molecular modeling of P americana and A lumbricoides tropomyosins was performed by using the MODELLER program. RESULTS A lumbricoides tropomyosin showed 69% to 98% sequence identity to tropomyosins from other invertebrates. The predicted structure of A lumbricoides tropomyosin was similar to that of P americana tropomyosin and showed the characteristic coiled-coil structure. Strong correlation was found for IgE antibodies to tropomyosins from A lumbricoides and P americana in sera from children living in a parasite-endemic area and from patients with cockroach allergy. Larvae of A lumbricoides reacted strongly with mAb 1A6. CONCLUSION Tropomyosin induces IgE responses in A lumbricoides-infected children and in patients allergic to cockroach.

Environmental contamination by Toxocara sp. eggs in Ribeirão Preto, São Paulo State, Brazil

Toxocariasis is a zoonosis mainly caused by Toxocara canis, an intestinal nematode of dogs. Man acquires the infection through accidental ingestion of viable eggs, and the toxocariasis clinical manifestations may vary from an asymptomatic infection up to the Visceral Larva Migrans syndrome. Seventy eight public squares of Ribeirão Preto, São Paulo, Brazil, including Bonfim Paulista district were visited aiming to evaluate the soil contamination by Toxocara eggs. The squares were divided in five different areas corresponding to the Sanitary Districts of the city. From May to December 2003, soil samples weighting about 250 g each were collected from five distinct sites of each public square. The laboratory analysis was done by centrifugal-flotation techniques in magnesium sulphate solutions with 5% of potassium iodide (d = 1.33) and zinc sulphate (d = 1.20), and by the sedimentation- flotation in conic chalices with zinc sulphate (d = 1.20). Toxocara sp. eggs were found on 16 (20.5%) squares, with the lowest prevalence (12%) at the central area. From these results, it is expected that the legal authority will adopt protection measures for the city public areas, reducing thus the contamination risk by Toxocara sp. eggs.

Epidemia de dengue em Ribeirão Preto, SP, Brasil: nota prévia

A preliminary note on an outbreak of dengue which occurred in the city of Ribeirão Preto, State of S. Paulo, Brazil, from November 1990 to March 1991, is given. One case of Level II Dengue Hemorrhagic Fever/Dengue Shock Syndrome (DHF/DSS) and two deaths associated with dengue related shock are described. Clinicians and epidemiologists are alerted to the possibility of sporadic DHF/DSS cases during outbreaks of classical dengue in formerly free areas.

Recurrent meningitis in a case of congenital anterior sacral meningocele and agenesis of sacral and coccygeal vertebrae

A rare case of recurrent meningitis due to congenital anterior sacral meningocele and agenesis of the sacral and coccygeal vertebrae is described. An autosomal dominant inheritance is demonstrated for lower cord malformation, and environmental factors (chromic acid or fumes) are discussed.

Vitamin A and the eye: an old tale for modern times

Clinical presentations associated with vitamin A deficiency persist in poor regions globally with the same clinical features as those described centuries ago. However, new forms of vitamin A deficiency affecting the eyes, which have become widespread, as a result of modern societal habits are of increasing concern. Ophthalmic conditions related to vitamin A deficiency require the combined attention of ophthalmologists, pediatricians, internists, dermatologists, and nutritionists due to their potential severity and the diversity of causes. As the eyes and their adnexa are particularly sensitive to vitamin A deficiency and excess, ocular disturbances are often early indicators of vitamin A imbalance. The present review describes the clinical manifestations of hypovitaminosis A with an emphasis on so-called modern dietary disorders and multidisciplinary treatment approaches. The present review also discusses the relationship between retinoic acid therapy and dry eye disease.