Intestinal amebiasis in Antofagasta, Chile]

In January 1989--December 1991 period we verified 35 cases of symptomatic intestinal amebiasis in Antofagasta, the main city of the North of Chile. Out of the total number of studied patients 23 were adults (77.1% males and 22.9% females) and all of them were permanent residents of Antofagasta. E.histolytica was frequently detected in association with other parasites and/or commensals, and observed alone in only seven cases. The clinical and epidemiological aspects of these 35 cases are discussed.     

A New Lignan (Polonilignan) and Inhibitors of Nitric Oxide Production from Penicillium polonicum,an Endophytic Fungi of Piper nigrum

Inhibiting nitric oxide (NO) or its production is found to be of therapeutic benefit. To discover natural small molecule inhibitors of NO production, a bioassay- and LC/MS-guided chemical investigation was done on the metabolites of endophytic fungus isolated from fresh Piper nigrum fruits. The isolated pure strain was identified as Penicillium polonicum by 16S rDNA sequence comparison. The culture broth extract of P. polonicum (EEPP) exhibited a significant reduction of NO production (Griess method) in LPS-stimulated RAW 264.7 cells (P<0.0001). To understand the chemical constituents of bioactive EEPP, column chromatography and p-TLC studies were carried out, which yielded eight pure compounds. They were characterised as botryosphaeridione ( 1 ), 3-(3,5-di-tert-butyl-4-hydroxy)phenylpropionic acid ( 2 ), variabilone ( 3 ), 2,4-di-tert-butylphenol ( 4 ), indole-3-carboxylic acid ( 5 ), tyrosol ( 6 ), ethyl ferulate ( 7 ) and a new lignan ( 8 ) based on the spectral analysis. The structure elucidation of the new lignan, named polonilignan ( 8 ), was based on HR-MS, ¹H- & ¹³C-NMR, H−H COSY, HSQC and HMBC spectra. Compounds 2 , 4 , 5 and 6 showed a significant decrease (P<0.0001) in the production of NO in LPS-induced RAW 264.7 cells. Tyrosol ( 6 ) and indole-3-carboxylic acid ( 5 ) controlled nitrite release with IC₅₀ values of 22.84 and 55.01 μM, respectively. This is the first report of (i) P. polonicum as an endophytic fungus of pepper fruits, (ii) isolation of compounds 1 – 8 except 6 from P. polonicum culture broth extract and (iii) NO inhibition effect of 2 , 4 , 5 and 6 .     

Multi-locus Sequence Typing and Whole Genome Sequence Analysis of Cryptococcus neoformans Isolated from Clinical Specimens in Vajira Hospital,Bangkok, Thailand

Mycopathologia - The basidiomycete yeast Cryptococcus neoformans causes disease in immunocompromized patients. Whole genome sequencing (WGS) technology provides insights into the molecular...     

Enzymatic Digestion of Roots for Recovery of Root-knot Nematode Developmental Stages

Developmental stages of Meloidogyne javanica were successfully released from roots by treatment with commercially available cellulase and pectinase. The average percentage recovery of nematode developmental stages from Dolichos lablab, Elymus glaucus, and Lycopersicon esculentum were as follows: eggs = 526%, J2 = 272%, J3 = 783%, J4 = 549%, adult females = 285%, and total = 425%, expressed as percentages of the counts obtained from stained roots spread on glass plates. Root digestion was more accurate and sensitive in detecting low numbers of nematodes in roots than was the glass plate method. No simple linear, quadratic, or cubic relationship was found between the two methods that would allow a conversion factor to be developed.     

Cloning, physical mapping and genome organization of mitochondrial DNA from Cyprinus carpio oocytes

Summary The mitochondrial genome from Cyprinus carpio oocytes is a 10.5 megadalton, circular DNA molecule. The carp mitochondrial DNA was cloned in pBR325. Three recombinant plasmids accounted for the entire genome. Mapping of this DNA using 11 different restriction endonucleases is reported here. Both the large and small rRNA genes were then localized using Southern blot analysis. The subunit I of the cytochrome oxidase, the cytochrome b, the tRNA^Glu and the URF 4 genes were localized by nucleotide sequence analysis and homology studies with human mtDNA.Our results suggest that a similar gene order has been maintained in the mitochondrial genomes of Chordata and support the hypothesis of a common ancestor for all vertebrate organelle genomes.This study constitutes the first report on the genome organization of a fish mtDNA and provides information for further investigation in connection with sequence determination, replication, and gene expression in carp mitochondria.This work was supported by proyect RS-82-21 from the Universidad Austral de Chile and Grant N^o 1116 from Fondo Nacional de Desarrollo Cientifico y Tecnologico