Phylogenetic affiliation of the desert truffles <Emphasis Type="Italic">Picoa juniperi</Emphasis> and <Emphasis Type="Italic">Picoa lefebvrei</Emphasis>

The molecular phylogeny and comparative morphological studies reported here provide evidence for the recognition of the genus Picoa, an hypogeous desert truffle, in the family Pyronemataceae (Ascomycota, Pezizales). Picoa juniperi and Picoa lefebvrei were reassigned to the genus Picoa based on large subunit (LSU) sequence (28S) rDNA and internal transcribed spacer (ITS) rDNA (including the partial 18S, ITS1, ITS2, 5.8S gene, and partial 28S of the nuclear rDNA) data. Morphological studies of spores, asci, perida, and gleba revealed high similarities between P. lefebvrei and P. juniperi, thereby confirming the membership of both species in the genus Picoa. These two species were primarily distinguishable based on ascospore ornamentation.     

Thermodynamic and structural analysis of interactions between peptide ligands and SEB

Staphylococcal enterotoxin B (SEB) is an exotoxin produced by Staphylococcus aureus and commonly associated with food poisoning. In this study, SEB‐binding peptides were identified by screening a phage displayed peptide library. The binding of peptides to SEB was tested with isothermal titration calorimetry (ITC) and of the five selected peptides, three showed affinity to SEB, with one measured to have the highest affinity constant (10⁵ M^?1). ITC revealed that the interaction of peptide ligands with SEB was driven entropically and the binding was dominated by hydrophobic interactions. Circular dichroism (CD) measurements and molecular dynamics (MD) simulations, together, give a structural insight into the interaction of peptides with SEB. While SEB binding peptides showed random coil structure before binding, after complex formation they had more ordered structures. The peptide with highest affinity to SEB showed stable conformation during MD simulation. Taken together, our approach about thermodynamic and structural characterization of peptide ligands can be used to develop aptamers, with high affinity and selectivity, for biosensor applications. Copyright © 2009 John Wiley & Sons, Ltd.     

Gender-dependent effects of selenite on the perfused rat heart

Gender differences are related to the manner in which the heart responds to chronic and acute stress conditions of physiological and pathological nature. Depending on dose, sodium selenite acts as an antioxidant proven to have beneficial effects in several pathological conditions G. Drasch, J. Schopfer, and G. N. Schrauzer, Selenium/cadmium ratios in human prostates: indicators of prostate cancer risk of smokers and non-smokers, and relevance to the cancer protective effects of selenium,Biol. Trace Element Res. 103(2), 103–107 (2005); R. G. Kasseroller and G. N. Schrauzer, Treatment of secondary lymphedema of the arm with physical decongestive therapy and sodium selenite: a review,Am. J. Ther. 7(4), 273–279 (2000); G. N. Schrauzer, Anticarcinogenic effects of selenium,Cell. Mol. Life Sci. 57(13–14), 1864–1873 (2000); I. S. Palmer and O. E. Olson, Relative toxicities of selenite and selenate in the drinking water of rats,J. Nutr. 104(3), 306–314 (1974). To date, little is known about the gender-dependent direct effects of toxic doses of selenite on electrophysiology of the cardiovascular system H. A. Schroeder and M. Mitchener, Selenium and tellurium in rats: effect on growth, survival and tumors,J. Nutr. 101(11), 1531–1540 (1971); G. N. Schrauzer, The nutritional significance, metabolism and toxicology of selenomethionine,Adv. Food Nutr. Res. 47, 73–112 (2003). In the present study, the effects of in vitro toxic concentrations of sodium selenite ranging from 10^-6 M to 10^-3 M were tested on both male and female rat heart preparations. The toxic effects seen in an electrocardiogram and left ventricular pressure were dose and sex dependent at most of the tested concentrations. The present study clearly shows that at toxic doses, stress conditions are induced by selenite, resulting in gender-dependent modifications of the heart function. This modification is more pronounced in the contraction cascade of female rats. Males, on the other hand, had been much more affected in excitation-related parameters.     

Differential diagnosis of Charcot arthropathy and osteomyelitis

Foot problems are common causes of morbidity in patients with diabetes mellitus. Foot ulcers are the leading cause of hospitalization in diabetic patients. Bones may be involved in two different clinical conditions: osteomyelitis and Charcot osteoarthropathy. Osteomyelitis usually develops by spreading from contiguous soft tissue to underlying bone. Charcot foot is deformation of foot as a result of muscle athrophy, bone and joint structure changes in a joint as a secondary complication of neuropathy. To distinguish bone infection from non-infectious bone disorders as in Charcot joint may be difficult, especially if there is no skin ulceration. So, the mere absence of skin ulcers does not exclude the diagnosis of osteomyelitis.     

The protective effects of caffeic acid phenethyl ester (CAPE) against liver damage induced by cigarette smoke inhalation in rats

The aim of this study was to investigate the histological and biochemical changes in liver of rats exposed to cigarette smoke and effects of caffeic acid phenetyl ester (CAPE) on these changes. For this purpose, 21 male Wistar rats were divided into three groups. Animals in Group I were used as control. Rats in Group II were exposed to cigarette smoke and rats in Group III were exposed to cigarette smoke and injected daily with CAPE. At the end of the 60-days experimental period, all rats were killed by decapitation and blood samples were obtained. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin levels and hepatic superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px ), malondialdehyde (MDA) contents were determined. Following routine histological procedures, liver tissue specimens were examined under a light microscope. The levels of ALT, AST, total bilirubin, SOD, GSH-Px and MDA were significantly increased in rats exposed to cigarette smoke compared with those of the controls. Light microscopic examination of liver specimens from rats exposed to cigarette smoke revealed mononuclear cell infiltration and that some of the hepatocytes had a hyperchromatic nucleus and enlarged sinusoids. The rats which were treated with CAPE along with cigarettes had partially attenuated histological changes associated with cigarette exposure. In conclusion, the damage inflicted by cigarette in the rat liver can be partially prevented by CAPE administration.     

Dosage-dependent switch from G protein-coupled to G protein-independent signaling by a GPCR

G-protein-coupled receptors (GPCRs) mostly signal through heterotrimeric G proteins. Increasing evidence suggests that GPCRs could function in a G-protein-independent manner. Here, we show that at low concentrations of an agonist, beta(2)-adrenergic receptors (beta(2)-ARs) signal through Galpha(s) to activate the mitogen-activated protein kinase pathway in mouse embryonic fibroblast cells. At high agonist concentrations, signals are also transduced through beta(2)-ARs via an additional pathway that is G-protein-independent but tyrosine kinase Src-dependent. This new dosage-dependent switch of signaling modes of GPCRs has significant implications for GPCR intrinsic properties and desensitization.     

Comamonas testosteroni bacteremia in a patient with perforated acute appendicitis. Short communication

Comamonas testosteroni is an uncommon isolate in the clinical laboratory as a human pathogen. C. testosteroni most commonly emerges in abdominal pathologies especially in perforated appendicitis. In Turkey we report first time a case of bacteremia due to this organism, in a 22-year-old man with perforated acute appendicitis. The organism was shown to be susceptible to routine antibiotics so it was easily eliminated even after having caused a bacteremia.     

Evaluation of arabinofuranosidase and xylanase activities of Geobacillus spp. isolated from some hot springs in Turkey

Some hot springs located in the west of Turkey were investigated with respect to the presence of thermophilic microorganisms. Based on phenotyping characteristics and 16S rRNA gene sequence analysis, 16 of the isolates belonged to the genus Geobacillus and grew optimally at about 60 degrees C on nutrient agar. 16S rRNA gene sequence analysis showed that these isolates resembled Geobacillus species by > or = 97%, but SDS-PAGE profiles of these 16 isolates differ from some of the other species of the genus Geobacillus. However, it is also known that analysis of 16S rRNA gene sequences may be insufficient to distinguish between some species. It is proposed that recN sequence comparisons could accurately measure genome similarities for the Geobacillus genus. Based on recN sequence analysis, isolates 11, IT3, and 12 are strains of G stearothermophilus; isolate 14.3 is a strain of G thermodenitrificans; isolates 9.1, IT4.1, and 4.5 are uncertain and it is required to make further analysis. The presence of xylanase and arabinofuranosidase activities, and their optimum temperature and pH were also investigated. These results showed that 7 of the strains have both xylanase and arabinofuranosidase activities, 4 of them has only xylanase, and the remaning 5 strains have neither of these activities. The isolates 9.1, 7.1, and 3.3 have the highest temperature optima (80 degrees C), and 7.2, 9.1, AO4, 9.2, and AO17 have the highest pH optima (pH 8) of xylanase. Isolates 7.2, AO4, AC15, and 12 have optimum arabinofuranosidase activities at 75 degrees C, and only isolate AC 15 has the lowest pH of 5.5.     

Comparative morphometric analysis of intraepidermal and dermal lymphocytes in early mycosis fungoides and some inflammatory dermatoses

OBJECTIVE: Early stage mycosis fungoides (MF) may be indistinguishable from some inflammatory dermatoses (IDs) histopathologically. Various morphologic features of lymphocytes in epidermis and dermis may help to differentiate early-stage MF from other IDs. STUDY DESIGN: We studied 25 cases of early-stage MF and 30 cases of various IDs with prominent exocytosis. The following nuclear variables were measured on dermal and epidermal lymphocytes in MF and IDs (control) groups: nuclear area and perimeter, area convex hull, perimeter convex hull, diameter equivalent circle, minimum feret, maximum feret and form factor. All measurements were done using routinely prepared and hematoxylin-eosin-stained slides. RESULTS: There were statistically significant differences (p < 0.01) for all of the morphometric variables between early-stage MF and IDs. CONCLUSION: Our results revealed that the nuclear contour irregularities of intraepidermal lymphocytes are higher than those of dermal lymphocytes in MF. Their nuclear geometry is also different. Comparison of the nuclear features of intraepidermal with dermal lymphocytes may provide additional support in the diagnosis of early-stage MF.