Serum insulin-like growth factor levels do not predict functional recovery after hospitalization in nonagenarian patients

AIM: To analyze the insulin-like growth factor 1 (IGF-1) serum levels in nonagenarian patients and to investigate the predictive capacity of this measure to assess the functional recovery of this population following hospitalization. METHODS: We performed a prospective study in 60 consecutive nonagenarian patients admitted for medical or surgical diseases. We assessed IGF-1 serum levels and nutritional status. The functional status was assessed using the Barthel index. Thirty-four patients were reinvestigated 3 months after discharge from hospital. RESULTS: The mean levels of IGF-1 were lower in nonagenarians than in younger patients. No relationship was found between IGF-1 levels and nutritional status. The decline in Barthel index values 3 months after discharge from hospital did not correlate with serum levels of IGF-1 on admission. CONCLUSION: IGF-1 serum levels in nonagenarian patients do not predict functional recovery after hospitalization.     

Proteolytic gut activities in the rice water weevil,Lissorhoptrus brevirostris Suffrian (Coleoptera: Curculionidae)

Digestive endoprotease activities of the rice water weevil, Lissorhoptrus brevirostris Suffrian (Coleoptera: Curculionidae), were characterized based on the ability of gut extracts to hydrolyze specific synthetic substrates, optimal pH, and hydrolysis sensitivity to protease inhibitors. Larvae of this species were found to use a complex proteolytic system that includes cathepsin D-, cathepsin B-, trypsin-, and chymotrypsin-like activities. Trypsin-like activity was evenly distributed among the anterior, middle, and posterior portions of the gut, whereas cathepsin B- and cathepsin D-like activities were mainly located in the anterior and middle sections, and the chymotrypsin-like activity was highest in the middle and posterior sections. Gelatin-containing native-PAGE gels indicated the presence of several aspartyl, cysteine, and serine protease forms and confirmed the spatial organization of the proteolytic digestive process.     

In vitro anti-herpetic activity of sulfated polysaccharide fractions from Caulerpa racemosa

A sulfated polysaccharide fraction was isolated from the hot water extract of the green alga Caulerpa racemosa and designated HWE. This polymer, which contained galactose, glucose, arabinose and xylose as the major component sugars, had [alpha](D)(30) + 46.2 degrees in water and contained 9% sulfate hemiester groups. Sugar linkage analysis indicates that HWE was branched and mainly contained 1,3- and 1,3,6-linked galactose, 1,3,4-linked arabinose, 1,4-linked glucose and terminal- and 1,4-linked xylose residues. Sulfation was deduced from infrared spectroscopy and methylation analysis to occur on O-6 of galactose and O-3 of arabinose. The native polysaccharide could be fractionated by size exclusion chromatography into two overlapping fractions and the major fraction has a hydrodynamic volume similar to that of 70 kDa dextran. HWE was a selective inhibitor of reference strains and TK(-) acyclovir-resistant strains of herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) in Vero cells, with antiviral effective concentration 50% (EC(50)) values in the range of 2.2-4.2 microg/ml and lacking cytotoxic effects. Furthermore, HWE did not exhibit anticoagulant properties at concentrations near the EC(50).     

unc-53 controls longitudinal migration in C. elegans

Cell migration and outgrowth are thought to be based on analogous mechanisms that require repeated cycles of process extension, reading and integration of multiple directional signals, followed by stabilisation in a preferred direction, and renewed extension. We have characterised a C. elegans gene, unc-53, that appears to act cell autonomously in the migration and outgrowth of muscles, axons and excretory canals. Abrogation of unc-53 function disrupts anteroposterior outgrowth in those cells that normally express the gene. Conversely, overexpression of unc-53 in bodywall muscles leads to exaggerated outgrowth. UNC-53 is a novel protein conserved in vertebrates that contains putative SH3- and actin-binding sites. unc-53 interacts genetically with sem-5 and we demonstrated a direct interaction in vitro between UNC-53 and the SH2-SH3 adaptor protein SEM-5/GRB2. Thus, unc-53 is involved in longitudinal navigation and might act by linking extracellular guidance cues to the intracellular cytoskeleton.     

Isolation,chemical investigation and antiviral activity of polysaccharides from Gracilaria corticata (Gracilariaceae,Rhodophyta)

Polysaccharides were sequentially extracted from the agarophyte Gracilaria corticata. Chemical analysis combined with infrared spectroscopy showed that the cold water extracted material consists mainly of a high molecular weight sulfated galactan. Most of the sulfate groups are alkali labile and are located at C-4 of the 1,3-linked D-galactose units and C-6 of the 1,4-linked L-galactose residues. The autoclaved extracts contain agar type polysaccharide having a high pyruvate content and a variable degree of methylation, but were contaminated with floridean starch. 1H-NMR studies indicate that methoxyl groups, when present, occur at C-6 of the 1,3-linked D-galactose units and C-2 of the 1,4-linked L-galactose residues of agar polymer. Bioassays showed that a high molecular weight galactan sulfate, exhibited selective antiviral activity against herpes simplex virus types 1 and 2, likely due to an inhibition of the initial virus attachment to the host cell.     

In Candida albicans,white-opaque switchers are homozygous for mating type

The relationship between the configuration of the mating type locus (MTL) and white-opaque switching in Candida albicans has been examined. Seven genetically unrelated clinical isolates selected for their capacity to undergo the white-opaque transition all proved to be homozygous at the MTL locus, either MTLa or MTLalpha. In an analysis of the allelism of 220 clinical isolates representing the five major clades of C. albicans, 3.2% were homozygous and 96.8% were heterozygous at the MTL locus. Of the seven identified MTL homozygotes, five underwent the white-opaque transition. Of 20 randomly selected MTL heterozygotes, 18 did not undergo the white-opaque transition. The two that did were found to become MTL homozygous at very high frequency before undergoing white-opaque switching. Our results demonstrate that only MTL homozygotes undergo the white-opaque transition, that MTL heterozygotes that become homozygous at high frequency exist, and that the generation of MTL homozygotes and the white-opaque transition occur in isolates in different genetic clades of C. albicans. Our results demonstrate that mating-competent strains of C. albicans exist naturally in patient populations and suggest that mating may play a role in the genesis of diversity in this pernicious fungal pathogen.     

Assessment of the Environmental Fate of the Biological Control Agent of Fire Blight, Pseudomonas fluorescens EPS62e, on Apple by Culture and Real-Time PCR Methods

The colonization of apple blossoms and leaves by Pseudomonas fluorescens EPS62e was monitored in greenhouse and field trials using cultivable cell counting and real-time PCR. The real-time PCR provided a specific quantitative method for the detection of strain EPS62e. The detection level was around 10² cells g (fresh weight)⁻¹ and the standard curve was linear within a 5-log range. EPS62e actively colonized flowers reaching values from 10⁷ to 10⁸ cells per blossom. In apple flowers, no significant differences were observed between population levels obtained by real-time PCR and plating, suggesting that viable but nonculturable (VBNC) cells and residual nondegraded DNA were not present. In contrast, on apple leaves, where cultivable populations of EPS62e decreased with time, significant differences were observed between real-time PCR and plating. These differences indicate the presence of VBNC cells or nondegraded DNA after cell death. Therefore, the EPS62e population was under optimal conditions during the colonization of flowers but it was stressed and poorly survived on leaves. It was concluded that for monitoring this biological control agent, the combined use of cultivable cell count and real-time PCR is necessary.