Cryptic diversity,multilocus phylogeny,and pathogenicity of cercosporoid fungi associated with common bean and cowpea

In recent years, common bean (Phaseolus vulgaris) and cowpea (Vigna unguiculata) plants in the north of Iran have exhibited symptoms resembling Cercospora leaf spot (CLS) disease. This study was initiated to elucidate the taxonomy and pathogenicity of cercosporoid taxa associated with leaf spot diseases of these two legume crops in Iran. A total of 138 samples with CLS symptoms were collected from cultivated common bean and cowpea species in northern Iran and subjected to microscopic examination, resulting in identification of 98 Cercospora and 59 Pseudocercospora samples. A six-locus phylogenetic analysis (ITS, actA, tef1, gapdh, his3, and cmdA) coupled with examination of the morphology of 42 representative isolates from these samples confirmed that several cercosporoid fungi occur on common bean and cowpea in Iran. Five Cercospora species (C. iranica, C. cf. flagellaris, Cercospora sp. G, Cercospora sp. T, and C. vignigena) and two Pseudocercospora species (P. griseola f. griseola and P. cf. cruenta) were found; of these, C. cf. flagellaris was the dominant species, occurring on both common bean and cowpea. Pathogenicity tests confirmed that all seven species could infect leaves of common bean and/or cowpea. This is the first report of C. iranica, Cercospora sp. G, and Cercospora sp. T associated with common bean and/or cowpea in the world. In addition, C. vignigena was recorded for the first time in Iran. Results achieved in this study will assist strategies for the management of CLS disease of common bean and cowpea.     

Effect of body mass index on severity and prevalence of varicocele

Varicocele is classified as grade I-III regarding its severity. This study was aimed to determine the correlation between height and weight with varicocele grade in 18-30 years age group. We enrolled 400 persons aged 18-30 years referred to the specialist's clinics of Tabriz Medical Sciences University or Medical Commission Since Sep. 2004 to Mar. 2005. First we divided the volunteers in two groups including Varicocele Group and Non-varicocele Group, then varicocele patients were classified to three grades considering the severity of the disease: severe (Grade III), moderate (Grade II) and mild (Grade I). Finally, the correlation between height, weight and Body Mass Index (BMI) was evaluated. There was a significant relation between height and grades of left-side varicocele; in other words the severity of disease was increased with height (p = 0.004). Also, height increased the prevalence ofvaricocele (p = 0.011). On the other hand, low weight and BMI increased the prevalence of varicocele (p = 0.000, p = 0.004) but did not affect the severity of disease (p = 0.364, p = 0.172). In conclusion, the height of patients directly affected the prevalence and severity of left-side varicocele which probably is related to length of left internal spermatic veins in these patients and increased hydrostatic pressure in taller patients. Also, the weight and BMI is effective on the prevalence of varicocele. It seems that slim and tall persons will benefit from evaluation while puberty.     

Protective effects of crocin against cisplatin-induced acute renal failure and oxidative stress in rats

Background. The major side effect of cisplatin, used in some tumours, is nephrotoxicity. Reactive oxygen species and oxidative damage are the most important factors in cisplatin-induced acute renal failure. The main purpose of this study is to investigate the protective effects of crocin against cisplatin-induced acute renal failure and oxidative stress in rat. Methods. In this study, animals were randomly divided into 5 groups (6 each). Group one received normal saline (2 ml/day, i.p.). Group two received a single dose of cisplatin (5 mg/kg, i.p.). Groups 3 to 5 received crocin (100, 200 and 400 mg/kg, i.p., respectively, for 4 consecutive days one hour before a single dose of cisplatin (5 mg/kg) only at the first day. Blood samples were taken out (on the fifth day) for measuring the level of urea and creatinine. The kidneys were removed for histopathological and biochemical examinations. Furthermore, 24-hour urinary factors were measured. Results. Blood urea, creatinine and urinary glucose and protein concentrations in crocin-treated groups were significantly lower than those of cisplatin-treated group in a dose-dependent manner. Histopathological studies showed a massive damage in S3 segment of proximal tubules in cisplatin-treated group. No damage was observed in crocin-treated groups. Crocin treatment resulted in a significant and dose-dependent reduction in malondialdehyde concentration as compared to the cisplatin-treated group. Moreover, crocin produced a significant elevation in total thiol and glutathione peroxidase concentrations, as compared with cisplatin-treated group. Conclusion. The results of the present study suggest that crocin has a protective effect against cisplatin-induced acute renal failure and relative oxidative stress.     

Bioassay Procedure for the Evaluation of Erythromycin Activity in Aquaculture Environments

A new bioassay procedure was developed for the detection of erythromycin in aquaculture samples using a strain of a Stenotrophomonas as an indicator organism. Conventional disk-plate and well-plate radial diffusion assay procedures were developed, as well as a third procedure using the same indicator organism in Luria-Bertani (LB) broth, supplemented with the indicator dye Brilliant Black (40 μg/mL) in a multi-well microtiter plate. For both the disk-plate and well-plate radial diffusion assays, the response reflected in the size (width) of the growth inhibition zone, which was linear over the tested concentration range of 0.05 to 2.0 μg erythromycidml. The limit of quantitation of the bioassay was at 0.05 μg erythro-mycidml. Among the three methods of assay tested with Stenotrophomonas sp., the semi-quantitative dye reduction method is easy to read and is not diffusion dependent. This method allows for processing of more samples and more replication on a single titer plate. This new indicator organism is specific for erythromycin when tested in the presence of other antibacterial agents, i.e., oxytetracycline (Terramycin®) and/or Romet-Ma. This new bioassay procedure is suitable for quantitation of low concentrations of erythromycin in aquaculture water and sediment samples.     

Acidification of a sandy grassland favours bacteria and disfavours fungal saprotrophs as estimated by fatty acid profiling

We have investigated the structure of a microbial community in semi-natural sandy grassland in southeast Sweden. The sand is rich in lime, but in most places the soil is decalcified in the upper layers, and therefore this site shows a large variation in pH within short distances. We collected samples at three different soil depths (0-10 cm, 10-20 cm and 20-30 cm) and found the pH to range from 5 to 8 in the topsoil and from 4.5 to 9.5 in the deepest layer. The abundance of saprophytic fungi and bacteria was investigated using signature phospholipid fatty acids and arbuscular mycorrhizal fungi (AMF) using the neutral lipid fatty acid 16:1ω5. The PLFA pattern of the topsoil was different from that in the other two layers, as indicated by principal component analysis. The saprotrophic fungi were associated with high pH, and bacteria with low pH in these sandy soils. No relation was found between pH and AMF in the topsoil, while a positive relation was found in the deepest soil layer. The saprophytic fungi-to-bacteria ratio was constant with depth, while the AMF-to-bacteria ratio increased with soil depth. The results showed that high soil pH favoured fungal saprophytes in sandy grasslands and that AMF are relatively more abundant than the other two groups in deeper soil layers; particularly so when the pH is high.     

Application of two-step laser mass spectrometry to cosmogeochemistry: direct analysis of meteorites

Polycyclic aromatic hydrocarbons in C1, C2, and C3 carbonaceous chondrites and in some ordinary chondrites have been directly analyzed by two-step laser desorption/ laser multiphoton ionization mass spectrometry, a selective and sensitive method requiring only milligram samples. At the ionization wavelength of 266 nanometers, parent ion peaks of polycyclic aromatic hydrocarbons dominate the mass spectra. Quantitative analysis is possible; as an example, the concentration of phenanthrene in the Murchison meteorite was determined to be 5.0 parts per million.     

Partial control of an ion-molecule reaction by selection of the internal motion of the polyatomic reagent ion

The ion-molecule reaction NH(3)(+) + ND(3) has been studied at various collision energies (1 to 5 electron volts in the center of mass) with preparation of the NH(3)(+) reagent in two nearly isoenergetic vibrational states. One state corresponds to pure out-of-plane bending of the planar NH(3)(+) ion (0.60 electron volts), whereas the other state is a combination of in-plane and out-of-plane motion (0.63 electron volts). The product branching ratios differ markedly for these two vibrational-state preparations. The differences in reactivity suggest that the in-plane totally symmetric stretching mode is essentially inactive in controlling the branching ratio of this reaction.