Non-smoking coke oven workers show an occupational PAH exposure-related increase in urinary mutagens

We examined the urinary mutagenicity in the YG1024 Salmonella typhimurium strain in the presence of S9 mix, of 31 male non-smoking coke oven workers and an equal number of controls matched for gender and dietary habits. Occupational PAH exposure to the workers was assessed by means of the individual urinary post-shift excretion of 1-pyrenol (mean +/- S.D.: 5.41 +/- 6.06 micromole/mol creatinine). Eleven urinary extracts of workers (35.5%) were clearly mutagenic (with at least a doubling of the number of spontaneous revertants), against only two samples in the control group (6.5%) (chi2-test; chi2 = 7.883; P < 0.01). Moreover, the mean mutagenic activity level corrected for dilution/concentration of the urine was about three times higher in coke oven workers than in matched controls (mean +/- S.D. (range) 495 +/- 407 (89.7-1603) versus 186 +/- 113 (14.2-524) net revertants/mmol creatinine; Mann-Whitney U-test, z = 3.86, P < 0.001). Simple linear regression analysis showed that the coke workers' urinary mutagenic activity is associated with the PAH occupation-related urinary excretion of 1-pyrenol (r = 0.41, P = 0.0215). This study definitely demonstrates an occupation-related exposure of coke oven workers' bladder epithelium to mutagenic PAH metabolites. This factor, mainly in the case of high exposure studied here, may account for a higher bladder cancer risk in coke oven workers.     

TP53 and p16INK4A, but not H-KI-Ras, are involved in tumorigenesis and progression of pleomorphic adenomas

The putative role of TP53 and p16(INK4A) tumor suppressor genes and Ras oncogenes in the development and progression of salivary gland neoplasias was studied in 28 cases of pleomorphic adenomas (PA), 4 cases of cystic adenocarcinomas, and 1 case of carcinoma ex-PA. Genetic and epigenetic alterations in the above genes were analyzed by Polymerase Chain Reaction/Single Strand Conformational Polymorphism (PCR/SSCP) and sequencing and by Methylation Specific-PCR (MS-PCR). Mutations in TP53 were found in 14% (4/28) of PAs and in 60% (3/5) of carcinomas. Mutations in H-Ras and K-Ras were identified in 4% (1/28) and 7% (2/28) of PAs, respectively. Only 20% (1/5) of carcinomas screened displayed mutations in K-Ras. p16(INK4A) promoter hypermethylation was found in 14% (4/28) of PAs and 100% (5/5) carcinomas. All genetic and epigenetic alterations were detected exclusively in the epithelial and transitional tumor components, and were absent in the mesenchymal parts. Our analysis suggests that TP53 mutations and p16(INK4A) promoter methylation, but not alterations in the H-Ras and K-Ras genes, might be involved in the malignant progression of PA into carcinoma.     

Identification of a novel sulfonated oxysterol, 5-cholesten-3beta,25-diol 3-sulfonate, in hepatocyte nuclei and mitochondria

This study reports the discovery of a novel sulfonated oxysterol found at high levels in the mitochondria and nuclei of primary rat hepatocytes after overexpression of the gene encoding steroidogenic acute regulatory protein (StarD1). Forty-eight hours after infection of primary rat hepatocytes with recombinant adenovirus encoding StarD1, rates of bile acid synthesis increased by 4-fold. Concurrently, [(14)C]cholesterol metabolites (oxysterols) were increased dramatically in both the mitochondria and nuclei of StarD1-overexpressing cells, but not in culture medium. A water-soluble [(14)C]oxysterol product was isolated and purified by chemical extraction and reverse-phase HPLC. Enzymatic digestion, HPLC, and tandem mass spectrometry analysis identified the water-soluble oxysterol as 5-cholesten-3beta,25-diol 3-sulfonate. Further experiments detected this cholesterol metabolite in the nuclei of normal human liver tissues. Based upon these observations, we hypothesized a new pathway by which cholesterol is metabolized in the mitochondrion.     

Agrobacterium-mediated transient transformation of marigold (Tagetes erecta)

Hypocotyls, roots, leaf sections and shoot tips from Tagetes erecta plantlets were inoculated with Agrobacterium tumefaciens, harboring the binary vector pCAMBIA2301, containing the β-glucuronidase gene. Histochemical GUS assays of infected tissues showed transient gus gene expression after 3 days.     

The multidimensionality of cell behaviors underlying morphogenesis: a case study in ascidians

Databases where different types of information from different sources can be integrated, cross-referenced and interactively accessed are necessary for building a quantitative understanding of the molecular and cell biology intrinsic to the morphogenesis of an embryo. Tassy and colleagues recently reported the development of software tailor-made to perform such a task, along with the generation and integration of three-dimensional anatomical models of embryos. They convincingly illustrated the utility of their approach by applying it to the early ascidian embryo.     

Epibiont protozoan communities on Caridina lanceolata (Crustacea, Decapoda) from the Malili lakes of Sulawesi (Indonesia)

The epibiont protozoan communities living on the freshwater shrimp Caridina lanceolata Woltereck, 1937a from the three major lakes (Towuti, Matano and Mahalona) of the Malili lake system (Sulawesi, Indonesia) were studied. The number of epibionts varied between 2 and 971 per shrimp. Seven protozoan ciliate species were found: Acineta sulawesiensis n. sp., Cothurnia sp., Zoothamnium sp. (in all three lakes), Vorticella sp. (Lake Mahalona and Lake Matano), Opercularia sp. (Lake Mahalona), Epistylis sp. (Lake Mahalona and Lake Matano), and Podophrya sp. (Lake Mahalona). Although these ciliates had been found previously on other crustaceans, they have not been observed as epibionts on Caridina H. Milne Edwards, 1837. The distribution of the different epibiont species on the anatomical units of the shrimp was analyzed in each lake. There is a statistical significant difference between the three lakes in respect to the number of epibionts on each anatomical unit of all analyzed shrimps. The total and mean densities of each epibiont species on the different analyzed shrimps showed a significant difference between the three lakes; i.e., the presence of each epibiont species on the population of C. lanceolata varied from one lake to another. In Lake Towuti the highest density of epibionts was found on the anterior part of the shrimp body (rostrum, antennae, antennulae and eyes) (32.41%), while in the other two lakes, the highest colonization corresponded to the maxillipeds (31.56% Lake Matano, 40.89% Lake Mahalona). In Lake Towuti the rest of epibionts colonized mainly maxillipeds and pleopods (both 45.76% of epibionts). In Lake Matano, other epibionts were distributed principally on the anterior part of the body and pleopods (in total 57.18% of epibionts). In Lake Mahalona, other epibionts were divided among the anterior part of the body, pereiopods and pleopods (in total 57.39% of the epibionts). Uropods and telson were the units less colonized in Lake Matano (3.64%) and Lake Mahalona (1.72%), while in Lake Towuti, they presented a moderate density (13.18% of the epibionts). Taking into account the distribution of epibionts along the antero-posterior axis of the shrimp, considering the different anatomical units, there was a significant correlation between the three lakes. This fact indicates that, in the three lakes, the colonization on C. lanceolata followed a similar distribution pattern, independently of the epibiont species present. The comparison between the distributions of the same epibiont species along the longitudinal axis of the shrimp on the diverse lakes showed that they correlated respect to their density values on the anatomical units of the shrimp. Diverse aspects of the colonization patterns are discussed. Morphological features, taxonomic identification, and particular distribution of the epibiont species in each lake are also included.     

Capture myopathy in little bustards after trapping and marking

Four little bustards (Tetrax tetrax) (one adult and three juvenile males), captured with leg nooses and fitted with a backpack radiotag, died after capture. The first bird was found after 16 days with its left foot caught in the harness and died after 1 day. The other birds showed symptoms of capture myopathy after release, such as the difficulty or inability to fly and/or walk. They died after 5, 6, and 8 days, respectively. At necropsy, muscles affected in all cases were those from the legs, and these were diffusely pale and dull, with a soft friable texture. Microscopically these muscles had multiple foci of myofiber fragmentation, loss of striation, and necrosis; a mononuclear cell infiltrate was observed in muscle from two birds. These findings suggest the little bustard is susceptible to capture myopathy and that caution should be exercised during its capture and handling.