Extracts from different parts of Melia azedarach L. were studied as potential antifungal agents for selected phytopathogenic fungi. In a serial agar dilution method, hexanic and ethanolic extracts from fruit, seed kernels, and senescent leaves exhibited fungistatic activity against Aspergillus flavus,Diaporthe phaseolorum var. meridionales, Fusarium oxysporum, Fusarium solani, Fusarium verticillioides, and Sclerotinia sclerotiorum. Both hexanic extract from senescent leaves and ethanolic extract from seed kernel were highly effective on all tested fungi, with minimum inhibitory concentration (MIC) values ranging from 0.5 to 25 mg/mL and 0.5 to 5 mg/mL, respectively. In addition, all of the above-mentioned extracts showed fungicidal activity on these fungi, with ethanolic seed kernel extract being the most active. Three compounds displaying activity against F. verticillioides were isolated from the ethanolic seed kernel extract and were characterized as vanillin (1), 4-hydroxy-3-methoxycinnamaldehyde (2), and (+/-)-pinoresinol (3), with MICs of 0.6, 0.4, and 1.0 mg/mL, respectively. These compounds also showed a synergistic effect when combined in different concentrations, needing four times less concentration to reach complete inhibition in the growth of F. verticillioides.

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Ž .Background: A possible relationship between Silica Si exposure and antineutrophil cytoplasm antibodies Ž . Ž . ANCA -associated vasculitis has been reported. Furthermore, tuberculosis TBC has been frequently described in patients with silicosis, and TBC infection shares with ANCA-associated vasculitis the formation of granulomas. Therefore, an intriguing network including Silica, Vasculitis, TBC and ANCA might be hypothesized. The aim of this work was to further investigate these correlations using both epidemiological and pathogenic approaches. Methods: Study I ᎏ epidemiological study. A case᎐control study to compare the occupational histories of 31 cases of biopsy Ž proven vasculitis 18 pauci-immune crescentic glomerulonephritis, 9 microscopic polyangitis, 4 Wegener's granulo-. Ž . matosis with those of 58 age, sex and residence-matched controls affected by other kidney diseases , was performed. Occupational Health physicians designed an appropriate questionnaire in order to evaluate a wide spread of exposures and calculate their entity by the product of Intensity = Frequency = Duration. Study II ᎏ tuberculosis Ž . association. A case᎐control study to evaluate the frequency of a previous history of tuberculosis TBC in 45 patients with vasculitis and 45 controls were performed. Study III ᎏ ANCA positi¨ity. A case᎐control study to evaluate the presence of ANCA was performed by testing blood samples of 64 people with previous professional exposure and 65 sexrage matched patients hospitalized in a General Medicine Unit. Furthermore, the same evaluation was made in a pilot study in 16 patients with ongoing or previous TBC. Study IV ᎏ experimental study. The oxygen free radicals U Corresponding author. Tel.: q39-11-6635594; fax: q39-11-6963158.Ž . E-mail address: strattanefro@hotmail.com P. Stratta . with an amorphous diatomaceous earth and a crystalline quartz form of Si at the doses of 10 and 100 g ml was evaluated. Results: Study I ᎏ a positive history of exposure to Si resulted in significantly more present in cases Ž . Ž . 14r31s 45% than in controls 14r58s 24%, Ps 0.04, ORs 2.4 and no other significant exposure association was Ž found including asbestos, mineral oil, formaldehyde, diesel and welding fumes, grain and wood dust, leather, . solvents, fungicides, bitumen, lead and paint . Study II ᎏ past TBC infection was significantly more present in Ž . Ž . patients with vasculitis 12r45s 26% than in controls 4r45 s 8%, P -0.05 . Study III ᎏ ANCA was present in Ž . 2r64 exposed people vs. 0r65 controls, Ps NS and 0r16 patients with TBC. Study IV ᎏ both amorphous and crystalline Si forms represented a stimulus for OFR and IL-12 production, but quartz resulted as a greater inductor. Conclusions: We conclude that Si exposure might be a risk factor for ANCA-associated vasculitis, possibly enhancing endothelial damage by phagocyte generation of oxygen free radicals and Th1 differentiation by an excessive IL-12 phagocyte production. Frequency of TBC was significantly higher in vasculitis patients. ANCA was...

Aflatoxin contamination is one of the main factors affecting peanut seed quality. One of the strategies to decrease the risk of peanut aflatoxin contamination is the use of genotypes with resistance to Aspergillus infection. This laboratory study reports the resistance to Aspergillus infection and aflatoxin contamination of six peanut genotypes inoculated with 21 Aspergillus isolates obtained from the peanut production region of Cordoba, Argentina. The resistance was investigated in the seed coat and cotyledons of three resistant genotypes (J11, PI 337394, and PI 337409) and three breeding lines (Manfredi 68, Colorado Irradiado, and Florman INTA) developed at the Instituto Nacional de Tecnologia Agropecuaria (INTA), Manfredi Experimental Station, Cordoba, Argentina. Resistance to fungal colonization and aflatoxin contamination was found to be associated with seed coat integrity in the PI 337394, PI 337409, and J11 genotypes, whereas the INTA breeding lines such as Colorado Irradiado showed a moderate resistance and the Manfredi 68 and Florman INTA genotypes the least resistance. Furthermore, another type of resistance associated with cotyledons was found only in the PI 337394 genotype.