Polyphasic characterization of “<Emphasis Type="Italic">Aspergillus nidulans</Emphasis> var. <Emphasis Type="Italic">roseus</Emphasis>” ATCC 58397

Polyphasic characterization of the echinocandin B producer Aspergillus nidulans var. roseus ATCC 58397 strain was carried out to elucidate its taxonomical status. According to its carbon source utilization and secondary metabolite spectrum as well as the partial β-tubulin, calmodulin, and γ-actin gene sequences, A. nidulans var. roseus belongs to the Emericella rugulosa species. Auxotroph mutants of A. nidulans var. roseus ATCC 58397 and E. rugulosa CBS 171.71 and CBS 133.60 formed stable heterokaryons on minimal medium with several A. nidulans strains, and in the case of A. nidulans var. roseus, even cleistothecia were developed.     

Vanilloid Receptor-1 (TRPV1) Expression and Function in the Vasculature of the Rat

Transient receptor potential (TRP) cation channels are emerging in vascular biology. In particular, the expression of the capsaicin receptor (TRPV1) was reported in vascular smooth muscle cells. This study characterized the arteriolar TRPV1 function and expression in the rat. TRPV1 mRNA was expressed in various vascular beds. Six commercially available antibodies were tested for TRPV1 specificity. Two of them were specific (immunostaining was abolished by blocking peptides) for neuronal TRPV1 and one recognized vascular TRPV1. TRPV1 was expressed in blood vessels in the skeletal muscle, mesenteric and skin tissues, as well as in the aorta and carotid arteries. TRPV1 expression was found to be regulated at the level of individual blood vessels, where some vessels expressed, while others did not express TRPV1 in the same tissue sections. Capsaicin (a TRPV1 agonist) evoked constrictions in skeletal muscle arteries and in the carotid artery, but had no effect on the femoral and mesenteric arteries or the aorta. In blood vessels, TRPV1 expression was detected in most of the large arteries, but there were striking differences at level of the small arteries. TRPV1 activity was suppressed in some isolated arteries. This tightly regulated expression and function suggests a physiological role for vascular TRPV1.     

Pancreatitis severity in mice with impaired CFTR function but pancreatic sufficiency is mediated via ductal and inflammatory cells-Not acinar cells

Mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR) are an established risk factor for cystic fibrosis (CF) and chronic pancreatitis. Whereas patients with CF usually develop complete exocrine pancreatic insufficiency, pancreatitis patients with CFTR mutations have mostly preserved exocrine pancreatic function. We therefore used a strain of transgenic mice with significant residual CFTR function (CFTR^tm1HGU) to induce pancreatitis experimentally by serial caerulein injections. Protease activation and necrosis were investigated in isolated acini, disease severity over 24h, pancreatic function by MRI, isolated duct stimulation and faecal chymotrypsin, and leucocyte function by ex vivo lipopolysaccharide (LPS) stimulation. Pancreatic and lung injury were more severe in CFTR^tm1HGU but intrapancreatic trypsin and serum enzyme activities higher than in wild-type controls only at 8h, a time interval previously attributed to leucocyte infiltration. CCK-induced trypsin activation and necrosis in acini from CFTR^tm1HGU did not differ from controls. Fluid and bicarbonate secretion were greatly impaired, whereas faecal chymotrypsin remained unchanged. LPS stimulation of splenocytes from CFTR^tm1HGU resulted in increased INF-γ and IL-6, but decreased IL-10 secretion. CFTR mutations that preserve residual pancreatic function significantly increase the severity of experimental pancreatitis—mostly via impairing duct cell function and a shift towards a pro-inflammatory phenotype, not by rendering acinar cells more susceptible to pathological stimuli.     

Identification of pathogenicity‐related genes in Fusarium oxysporum f. sp. cepae

Pathogenic isolates of Fusarium oxysporum, distinguished as formae speciales (f. spp.) on the basis of their host specificity, cause crown rots, root rots and vascular wilts on many important crops worldwide. Fusarium oxysporum f. sp. cepae (FOC) is particularly problematic to onion growers worldwide and is increasing in prevalence in the UK. We characterized 31 F. oxysporum isolates collected from UK onions using pathogenicity tests, sequencing of housekeeping genes and identification of effectors. In onion seedling and bulb tests, 21 isolates were pathogenic and 10 were non‐pathogenic. The molecular characterization of these isolates, and 21 additional isolates comprising other f. spp. and different Fusarium species, was carried out by sequencing three housekeeping genes. A concatenated tree separated the F. oxysporum isolates into six clades, but did not distinguish between pathogenic and non‐pathogenic isolates. Ten putative effectors were identified within FOC, including seven Secreted In Xylem (SIX) genes first reported in F. oxysporum f. sp. lycopersici. Two highly homologous proteins with signal peptides and RxLR motifs (CRX1/CRX2) and a gene with no previously characterized domains (C5) were also identified. The presence/absence of nine of these genes was strongly related to pathogenicity against onion and all were shown to be expressed in planta. Different SIX gene complements were identified in other f. spp., but none were identified in three other Fusarium species from onion. Although the FOC SIX genes had a high level of homology with other f. spp., there were clear differences in sequences which were unique to FOC, whereas CRX1 and C5 genes appear to be largely FOC specific.     

Obesity and aging affects skeletal muscle renin–angiotensin system and myosin heavy chain proportions in pre-diabetic Zucker rats

Journal of Physiology and Biochemistry - There is a gap in the knowledge regarding regulation of local renin–angiotensin system (RAS) in skeletal muscle during development of obesity and...     

Diversity of reed (Phragmites australis) stem biofilm bacterial communities in two Hungarian soda lakes

From reed biofilm samples of Kelemen-szék (Kiskunság National Park, KNP) and Nagy-Vadas (Hortobágy National Park, HNP) altogether 260 bacterial isolates were gained after serial dilutions and plating onto different media. Following a primary selection 164 strains were investigated by "traditional" phenotypic tests and clustered by numerical analysis. Fifty-six representative strains were selected to ARDRA and 16S rDNA sequence analysis for identification. Strains were identified as members of genera Agrobacterium, Paracoccus, Halomonas, Pseudomonas, Bacillus, Planococcus and Nesterenkonia. The species diversity was also investigated by a cultivation independent method. A clone library was constructed using the community DNA isolated from the biofilm sample of Kelemen-szék. Screening of the 140 bacterial clones resulted in 45 different ARDRA groups. Sequence analysis of the representatives revealed a great phylogenetic diversity. A considerable majority of the clones was affiliated with uncultured bacterial clones (with sequence similarity between 93 and 99%) originating from diverse environmental samples (for example salt marshes, compost or wastewater treatment plants). The DNA sequences of other clones showed the presence of genera Flavobacterium, Sphingobacterium, Pseudomonas and Agrobacterium.     

Photosynthetic characteristics and physiological plasticity of an Aphanizomenon flos-aquae (Cyanobacteria, Nostocaceae) winter bloom in a deep oligo-mesotrophic lake (Lake Stechlin, Germany)

In winter of 2009/2010, Aphanizomenon flos-aquae bloomed in the ice and snow covered oligo-mesotrophic Lake Stechlin, Germany. The photosynthesis of the natural population was measured at eight temperatures in the range of 2–35°C, at nine different irradiance levels in the range of 0–1,320 μmol m⁻² s⁻¹ PAR at each applied temperature. The photoadaptation parameter (I _k) and the maximum photosynthetic rate (P _max) correlated positively with the temperature between 2 and 30°C, and there was a remarkable drop in both parameters at 35°C. The low I _k at low temperatures enabled the active photosynthesis of overwintering populations at low irradiance levels under ice and snow cover. The optimum of the photosynthesis was above 20°C at irradiances above 150 μmol m⁻² s⁻¹. At lower irradiance levels (7.5–30 μmol m⁻² s⁻¹), the photosynthesis was the most intensive in the temperature range of 2–5°C. The interaction between light and temperature allowed the proliferation of A. flos-aquae in Lake Stechlin resulting in winter water bloom in this oligo-mesotrophic lake. The applied 2°C is the lowest experimental temperature ever in the photosynthesis/growth studies of A. flos-aquae, and the results of the P–I and P–T measurements provide novel information about the tolerance and physiological plasticity of this species.     

Glial cells in the central nervous system of earthworm, Eisenia fetida

Glial elements in the central nervous system of Eisenia fetida were studied at light- and electron microscopic level. Cells were characterized with the aid of toluidine blue, Glial Fibrillary Acidic Protein (GFAP), S100 staining. We identified neurilemmal-, subneurilemmal-, supporting-nutrifying- and myelinsheath forming glial cells. Both neuronal and non-neuronal elements are S100-immunoreactive in the CNS. Among glial cells neurilemmal and subneurilemmal cells are S100-immunopositive. With the antibody against the S100 protein one band is visible at 15 kDa. GFA P-immunopositive supporting-nutrifying glial cells are localized around neurons and they often appear as cells with many vacuoles. GFA P-positive cell bodies of elongated neurilemmal glial cells are also visible. Western blot analysis shows a single 57 kDa GFA P immunoreactive band in the Eisenia sample. At ultrastructural level contacts between neuronal and glial cells are recognizable. Glial cell bodies and their filopodia contain a granular and vesicular system. Close contacts between neuronal cell membranes and glial filopodia create a special environment for material transport. Vesicles budding off glial cell granules move towards the cell membranes, probably emptying their content with kiss and run exocytosis. The secreted compounds in return may help neuronal survival, provide nutrition, and filopodia may also support neuronal terminals.