Non-malignant silica-related diseases in a specialized outpatient clinic.

BACKGROUND: Uncontrolled occupational exposure to silica is still frequent in Brazil, with several recent records in the state of Minas Gerais. However, few national studies have addressed silica-related diseases other than silicosis. AIMS: To describe the occurrence of the main non-malignant silica-related diseases: silicosis, tuberculosis (TB), chronic obstructive pulmonary disease (COPD), and autoimmune diseases in a specialized outpatient clinic. METHODS: Case series study of 1525 patients exposed to silica, seen between 1984 and 2021, with descriptive findings of clinical and occupational data from the first medical evaluation. RESULTS: Medians of age and exposure time were 47 and 15 years, respectively, and 97% of patients were male. The prevalence of silicosis was 44%, of which 27% had large opacities. The main occupational sectors were underground gold mining (28%), precious and semi-precious stone work (20%), and artisanal mining (9%). Spirometries were abnormal in 55%, with obstructive disorder being the most common finding. COPD (25%), active TB or sequelae (12%), and connective tissue diseases (6%) were diagnosed in patients with and without silicosis. CONCLUSIONS: The percentage of silicosis appears to be alarming, even considering the biases of selective referrals. The patients were relatively young and already had a functional impact, caused not only by silicosis but by one or more silica-related diseases. COPD, TB, and connective tissue diseases proved to be frequent, leading to the need for specifics protocols to investigate them in individuals exposed to silica. By adopting strategies to combat silicosis, the prevention of other silica-related diseases is concomitantly promoted.

First record of Anastrepha serpentina (Wiedemann) (Diptera: Tephritidae) in citrus in Brazil.

Anastrepha serpentina (Wiedemann) is recorded for the first time in citrus (Rutaceae) in Brazil. Specimens were obtained from sweet orange (Citrus sinensis) sampled in the municipalities of Belém and Capitão Poço, and from mandarin orange (Citrus reticulata) from Tomé-Açu, state of Pará, Brazil.

Effects of condensed tannin from Acacia mearnsii on sheep infected naturally with gastrointestinal helminthes.

The effect of tannins on endoparasite control in hair sheep was investigated using 20 entire lambs of the Santa Inês breed. At the beginning of the experiment these animals were 6-months old and weighed 22.5kg+/-4.7. The treatments used were (10 animals each): GT (animals receiving 18g of Acácia negra containing 18% of condensed tannin/animal/week) and GC (animals not receiving tannin). The experiment lasted 84 days, with animals kept on an Andropogon gayanus pasture. Faeces were collected weekly, with weighing and blood collection carried out fortnightly. At slaughter, the adult worms were harvested for identification and counting. Although the GT animals weighed more than the GC lambs at slaughter, these differences were not significant (P>0.05). In general, the values for haemoglobin, hematocrit, total protein, urea, phosphorus and calcium in the serum were within normal levels and no significant differences between groups were observed. For faecal egg count (FEC), lower values were observed throughout the experiment in the group receiving tannin, but these differences were only significant in the eighth week. There was a lower output of eggs by regression for GT compared with GC (P<0.05). The species identified, in decreasing order of worm count, were: Trichostrongylus colubriformis, Haemonchus contortus, Oesophagostomum columbianum, Cooperia sp., Strongyloides papillosus, Trichuris globulosa and Moniezia expansa. The total worm count and number of each species of worm were lower for GT compared with GC for T. colubriformis and Cooperia sp. (P<0.05). Condensed tannin (CT) from A. negra had an antiparasitic effect, thereby representing an alternative for worm control in sheep.

Functional characterization and epitope analysis of a recombinant dermonecrotic protein from Loxosceles intermedia spider.

In the present study the recombinant form (recLiD1) of a dermonecrotic protein present in the Brazilian brown spider Loxosceles intermedia venom was expressed in Escherichia coli cells and purified by reversed-phase HPLC using a C8 Vydac column. About 25.8mg of purified recLiD1 was produced from a litre of bacterial culture. SDS/PAGE and immunoblot analysis of the recombinant protein revealed an apparent molecular weight of 32-35kDa. The later result was confirmed by mass spectrometry (32,758Da). recLiD1 displayed dermonecrotic and platelet aggregation activities which were qualitatively similar to that displayed by the crude L. intermedia venom. However, very low sphingomyelinase D enzymatic activity and complement-dependent haemolytic activities were observed. recLiD1 immunized BALB/c mice developed an antibody response. Anti-recLiD1 antibodies recognized L. intermedia venom in an indirect enzyme-linked immunosorbent assay (ELISA) and cross-reacted with crude venoms from L. intermedia, L. gaucho and L. laeta. An in vivo protection assay carried out 5 weeks after the end of the immunization protocol showed that 75% of the vaccinated mice could resist the challenge by 2.5LD(50) of L. intermedia venom. To characterize epitopes associated with protective antibodies, we prepare sets of immobilized synthetic 15 mer overlapping peptides covering the complete amino acid sequences of the recLiD1. Antibodies revealed one antigenic region in the N-terminal part of the toxin. The amino acid sequence of this epitope was found in several dermonecrotic proteins and some of its residues have been implicated with the active site of the toxin.