Similar Banding Patterns Research Articles

Differential Distribution of Salmonella Serovars and Campylobacter spp. Isolates in Free-Living Crows and Broiler Chickens in Aomori, Japan.

Salmonella and Campylobacter cause foodborne enteritis mainly via the consumption of raw/undercooked contaminated poultry meat and products. Broiler flocks are primarily colonized with these bacteria; however, the underlying etiology remains unclear. The present study was conducted in order to obtain further information on the prevalence and genotypic distribution of Salmonella and Campylobacter in free-living crows and broiler flocks in a region for 2 years, thereby facilitating estimations of the potential risk of transmission of C. jejuni from crows to broiler flocks. Salmonella serovars Bredeney and Derby were isolated from 8 and 3 out of 123 captured crows, respectively, both of which are not common in broiler chickens. Campylobacter were isolated from all 89 crows tested and C. jejuni was prevalent (85 crows). Pulsed field gel electrophoresis showed broad diversity in the crow isolates of C. jejuni. However, 3 crow isolates and 2 broiler isolates showing similar banding patterns were assigned to different sequence types in multi-locus sequence typing. These results indicate that crows do not share Salmonella serovars with broilers, and harbor various genotypes of C. jejuni that differ from those of broiler flocks. Thus, our results indicate that crows are not a potential vector of these bacteria to broiler flocks in this region.

Assessment of genetic diversity of Canthium parviflorum Lam by RAPD and ISSR markers

Canthium parviflorum Lam is an important medicinal plant widely used in traditional systems of medicine with propagation limitations. In the present work, we are reporting the genetic diversity analysis of naturally occurring and in vitro grown plants by RAPD and ISSR markers. The plants developed on MS medium supplemented with BA (2mg/l) and NAA (0.5mg/l) using nodal and leaf explants were used along with plants present in five different geographical areas. Genetic diversity analysis using DNA based markers, RAPD and ISSR indicated that considerable genetic variations are present in naturally occurring plants. It is also indicated that tissue culture plants and their wild relatives show genetic similarity by grouping into one clad. The amplification products of the regenerated plants showed similar banding patterns to that of the mother plant thus demonstrating the homogeneity of the micropropagated plants. The variations observed in naturally occurring plants could be due to the impact of local environmental factors and accumulation of mutations in the course of evolution. This is the first report on genetic diversity of Canthium plant populations.

Effect of biosynthesized silver nanoparticles on native soil microflora via plant transport during plant-pathogen-nanoparticles interaction.

In this study, the interaction of biosynthesized silver nanoparticles (BSNP) with native soil via plant transport was assessed in model pathosystem of Arabidopsis thaliana and Alternaria brassicicola. Foliar application of 5μg/mL of BSNP reduced number of spores of fungi to 2.2×105 from 7×105, while numbers of lesions got reduced to 0.9/leaf in treated plants compared to 2.9/leaf in pathogen-infected plant without altering soil pH, electric conductivity, soil organic carbon and soil microbial biomass carbon. Soil enzyme activities including dehydrogenase, acid and alkaline phosphatase, urease, β-glucosidase and protease did not alter significantly in BSNP-treated plants compared to control plants. Application of BSNP did not alter the number of cultivable bacteria, fungi and actinomycetes. Effect of BSNP on uncultured bacterial diversity was measured by DGGE analysis which revealed similar banding pattern in all different treatments except in A. brassicicola-infected (AB) and A. brassicicola-infected plants treated with silver nanoparticles (AB+BSNP) after 120days. Although AB-infected plants exhibited a decrease in bacterial diversity, treatment of AB+BSNP after 120days demonstrated maximum bacterial diversity. McIntosh, Shannon, and Simpson diversity indices were calculated based on carbon source utilization pattern by BIOLOG analysis, revealing no significant difference among all treatments in different time intervals. BSNPs have the potential to act as strong antimicrobial agent for plant disease management without altering the native soil microflora.

Antibody Banding Patterns of the Enzyme-Linked Immunoelectrotransfer Blot and Brain Imaging Findings in Patients With Neurocysticercosis.

The enzyme-linked immunoelectrotransfer blot (EITB) assay is the reference serological test for neurocysticercosis (NCC). A positive result on EITB does not always correlate with the presence of active infections in the central nervous system (CNS), and patients with a single viable brain cyst may be EITB negative. Nonetheless, EITB antibody banding patterns appears to be related with the expression of 3 protein families of Taenia solium, and in turn with the characteristics of NCC in the CNS (type, stage, and burden of viable cysts). We evaluated EITB antibody banding patterns and brain imaging findings of 548 NCC cases. Similar banding patterns were grouped into homogeneous classes using latent class analysis. The association between classes and brain imaging findings was assessed. Four classes were identified. Class 1 (patients negative or only positive to the GP50 band, related to the protein family of the same name) was associated with nonviable or single viable parenchymal cysticerci; class 2 (patients positive to bands GP42-39 and GP24, related to the T24-42 protein family, with or without anti-GP50 antibodies) was associated with intraparenchymal viable and nonviable infections; classes 3 and 4 (positive to GP50, GP42-39, and GP24 but also responding to low molecular weight bands GP21, GP18, GP14, and GP13, related to the 8 kDa protein family) were associated with extraparenchymal and intraparenchymal multiple viable cysticerci. EITB antibody banding patterns correlate with brain imaging findings and complement imaging information for the diagnosis of NCC and for staging NCC patients.

Performance and Fouling in Pre-Denitrification Membrane Bioreactors Treating High-Strength Wastewater from Food Waste Disposers

The study investigated the performance of the pre-denitrification membrane bioreactor (MBR) process to treat high-strength wastewater generated from food waste disposals. Extracellular polymeric substances (EPS) as membrane foulant and microbial community profiles were analyzed under different hydraulic retention time (HRT) operation conditions. The pre-denitrification MBR was effective for treating food wastewater with high chemical oxygen demand (COD)/N resulting in high total nitrogen (TN) removal efficiency. The operational data showed that effluent qualities in terms of COD, TN, and TP improved with longer HRT. However, membrane fouling potential as shown by specific membrane fouling rate and specific resistance to filtration (SRF) increased as HRT increased. The longer HRT conditions or lower influent loading led to higher levels of bound EPS while HRT did not show large effects on the level of soluble microbial products (SMP). The restriction fragment length polymorphism (RFLP) analysis showed similar microbial banding patterns from the sludges generated under different HRT conditions, indicating that HRT had minimal effects on the composition of microbial communities in the system. All these results suggest that the MBR with pre-denitrification is a feasible option for treating high-strength food wastewater and that different HRT conditions could affect the operational performance and the fouling rate, which is governed via changes in microbial responses through EPS in the system.

Evidence of persistence of Prevotella spp. in the cystic fibrosis lung.

Purpose. Prevotella spp. represent a diverse genus of bacteria, frequently identified by both culture and molecular methods in the lungs of patients with chronic respiratory infection. However, their role in the pathogenesis of chronic lung infection is unclear; therefore, a more complete understanding of their molecular epidemiology is required.Methodology. Pulsed Field Gel Electrophoresis (PFGE) and Random Amplified Polymorphic DNA (RAPD) assays were developed and used to determine the degree of similarity between sequential isolates (n=42) from cystic fibrosis (CF) patients during periods of clinical stability and exacerbation.Results. A wide diversity of PFGE and RAPD banding patterns were observed, demonstrating considerable within-genus heterogeneity. In 8/12 (66.7 %) cases, where the same species was identified at sequential time points, pre- and post-antibiotic treatment of an exacerbation, PFGE/RAPD profiles were highly similar or identical. Congruence was observed between PFGE and RAPD (adjusted Rand coefficient, 0.200; adjusted Wallace RAPD->PFGE 0.459, PFGE->RAPD 0.128). Furthermore, some isolates could not be adequately assigned a species name on the basis of 16S rRNA analysis: these isolates had identical PFGE/RAPD profiles to Prevotella histicola.Conclusion. The similarity in PFGE and RAPD banding patterns observed in sequential CF Prevotella isolates may be indicative of the persistence of this genus in the CF lung. Further work is required to determine the clinical significance of this finding, and to more accurately distinguish differences in pathogenicity between species.

Bacterial Leaf Spot of Araliaceous Plants Caused by Xanthomonas campestris pv. Hederae in Egypt

A leaf spot symptoms consentient with bacterial leaf spot disease of araliaceous plants were observed on plants of Schefflera actinophylla grown in different plots located in Cairo and Giza governorates during 2014. Eight bacterial isolates resemble Xanthomonas campestris pv. hederae obtained from symptomatic plants were characterized based on physiological and biochemical tests, pathogenicity test and Biolog microbial ID system. Furthermore, the isolates were characterized by comparing them by ERIC PCR which showed highly similar DNA fragment banding patterns between all isolates. Some variance in the isolates virulence were detected when differences in virulence between the isolates were evaluated on the leaves of Schefflera actinophylla and Schefflera elegantissima. Host range of the isolates within Araliaceae family was determined on 7 araliaceous plants where, all isolates were pathogenic on Schefflera arboricola, Schefflera elegantissima and Hedera helix in addition to Schefflera actinophylla and conversely, none of the isolates were pathogenic on Aralia nudicaulis, Dendropanax trifidus and Fatsia japonica. Incidence and severity of the disease were evaluated on araliaceous plants grown in 10 plots located in Cairo and Giza governorates. The disease incidence values significantly differed within surveyed plots whereas these values ranged from 0 to 56.5 % by overall mean equal to 22.9%. The mean of the disease severity ratings ranged from 38.0 to 77.5 % by overall mean equal to 43.5%.

Exploring genotype concordance in epidemiologically linked cases of tuberculosis in New York City.

Comparing genotype results of tuberculosis (TB) isolates from individuals diagnosed with TB can support or refute transmission; however, these conclusions are based upon the criteria used to define a genotype match. We used a genotype-match definition which allowed for variation in IS6110 restriction fragment length polymorphism (RFLP) to support transmission between epidemiologically linked persons. Contacts of individuals with infectious TB (index cases) diagnosed in New York City from 1997 to 2003 who subsequently developed TB (contact cases) from 1997 to 2007 were identified. For each contact case and index case (case-pair), isolate genotypes (spoligotype and RFLP results) were evaluated. Isolates from case-pairs were classified as exact or non-exact genotype match. Genotypes from non-exact match case-pairs were reviewed at the genotyping laboratory to determine if the isolates met the near-genotype-match criteria (exactly matching spoligotype and similar RFLP banding patterns). Of 118 case-pairs identified, isolates from 83 (70%) had exactly matching genotypes and 14 (12%) had nearly matching genotypes (supporting transmission), while the remaining 21 (18%) case-pairs had discordant genotypes (refuting transmission). Using identical genotype-match criteria for isolates from case-pairs epidemiologically linked through contact investigation may lead to underestimation of transmission. TB programmes should consider the value of expanding genotype-match criteria to more accurately assess transmission between such cases.

Effect of cytokinin combined elicitors (l-phenylalanine, salicylic acid and chitosan) on in vitro propagation, secondary metabolites and molecular characterization of medicinal herb – Coleus aromaticus Benth (L)

This study investigated the effect of cytokinin combined elicitors (l-phenylalanine, Salicylic acid and chitosan) on in vitro propagation of Coleus aromaticus. Furthermore, we determined the elicitor induced changes on genetic stability through Random amplified polymorphic DNA (RAPD), secondary metabolites and Phenylalanine ammonia lyase (PAL) gene expression. In in vitro propagation, the explant source of shoot tips and nodal explants were cultured on Murashige and Skoog (MS) medium with 0.5, 1.0, 1.5, 2.0 and 2.5mg/l of cytokinins (Benzyl amino purine (BAP), Kinetin (KIN)) for shoot bud induction. Further, nodal explants derived shoots cultured on the combination of 1.0mg/l of BAP with 0.5, 1.0, 1.5, 2.0, 2.5mg/l of l-Phe, 0.2, 0.4, 0.6, 0.8, 1.0mg/l of SA and 20, 40, 60, 80 of mg/l of Ch individually. The 79.81% of shoot bud induction was obtained with 1.0mg/l of BAP supplemented nodal explants. In multiple shoot development, 87% of multiple shoot development was obtained in the combination of 1.0mg/l BAP and 40mg/l chitosan supplemented culture. The developed shoots were rooted with 0.5mg/l of Naphthalene acetic acid (NAA) and transplanted to greenhouse condition with 75% survival rate. In vitro regenerated plants were subjected to RAPD profiling and it was exposed a similar banding pattern with that the mother plant. In secondary metabolites, compared to in vivo control the higher percentage of alkaloids (16), flavonoids (24), saponins (7.5), terpenoids (6.2), total phenolic content (24.4) and tannins (8) with increased PAL gene expression was analyzed in in vitro regenerated plants. Hence, this study shows that the choice of cytokinin combined elicitors supplementation during tissue culture noticeably influences not only multiple shoot development, but also the production of secondary metabolites without genetic modification.

Single Strand Conformational Polymorphism as a Molecular Marker for Detection of Variation between the Small Length ss DNA of Azospirillum, Phosphobacteria and Pseudomonas from the inoculated Bhendi field (COBH 1)

<em>Single strand conformational polymorphism is used to identify specific microorganism from the microbial ecosystem at field level. Here the double strand DNA of each organism is converted to single strand and allowed to run in polyacrylamide gel. SSCP can differentiate small variation within same length DNA of different organism due to the difference in retention time, temperature, ionic strength and electrophorotic mobility of ss DNA. This concept is used in this experiment to identify the inoculated microbial consortium from the field by comparison with microbial consortium and pure culture. Azospirillum (Azospirillum brasilense sp 7) and phosphobacteria (Bacillus megaterium var. phosphaticum) and Pseudomonas<strong> </strong>fluorescens (Pf 1) cultures were used for development of liquid microbial consortium for precision farming system. Inoculated microbes from the field were identified through SSCP –PCR analysis. Appearance of unique domain of V<sub>1</sub> to V<sub>9</sub> region of 16srRNA is universal for all bacteria and archae microbial community. Universal primers were used to amplify the V<sub>1</sub> to V<sub>2</sub> region of 16srRNA gene of pure culture, microbial consortium and soil sample from inoculated field for SSCP gel electrophoresis. This study revealed that similar banding pattern was observed between soil sample from inoculated field, microbial consortiums and pure cultures. This experiment proved that SSCP gel electrophoresis is a powerful technique to find specific microorganism in the field in comparison with its pure culture strains without characterization of microorganism. </em>

Genetic and phenotypic comparisons of viral genotypes from two nucleopolyhedroviruses interacting with a common host species, Spodoptera litura (Lepidoptera: Noctuidae)

Nucleopolyhedroviruses (NPVs) are known to be highly variable, both genetically and phenotypically, at several scales such as different geographic locations or a single host. A previous study using several geographic isolates indicated that two types of NPV, Spodoptera littoralis NPV (SpliNPV) and S. litura NPV (SpltNPV) types, were isolated from the common cutworm, Spodoptera litura (Fabricius), a polyphagous insect that causes serious damage to many forage crops and vegetables. That study also indicated that the SpliNPV type was widely distributed in Japan. Here, we investigated the genotypic and phenotypic variation of cloned NPVs that infect S. litura; such variation is an important resource for biological control agents, and may represent the genetic diversity of an NPV species. Eighteen genotypically distinct NPVs were cloned from four field-collected NPV isolates using an in vivo cloning technique. They were divided into two virus types according to the similarity of banding patterns of DNA fragments generated by restriction endonucleases, and Southern hybridization analysis. Partial polyhedrin gene sequences revealed that the two types corresponded to SpliNPV and SpltNPV. Bioassays seem to suggest that the SpliNPV virus type was, overall, more infectious and killed S. litura larvae faster, but yielded fewer viral occlusion bodies, than the SpltNPV type. These data provide a basis for explaining the distribution pattern of SpliNPV and SpltNPV types in S. litura populations in Japan.

Experimental, DFT and molecular docking studies on 2-(2-mercaptophenylimino)-4-methyl-2H-chromen-7-ol

A new coumarin derivative 2-(2-mercaptophenylimino)-4-methyl-2H-chromen-7-ol (COMSB) was synthesized and characterized with the help of 1H,13C NMR, FT-IR, FT-Raman and mass spectrometry. All quantum calculations were performed at DFT level of theory using B3LYP functional and 6-31G (d,p) as basis set. The UV–Vis spectrum studied by TD-DFT theory, with a hybrid exchange-correlation functional using Coulomb-attenuating method (CAM-B3LYP) in solvent phase gives similar pattern of bands, at energies and is consistent with that of experimental findings. The detailed analysis of vibrational (IR and Raman) spectra and their assignments has been done by computing Potential Energy Distribution (PED) using Gar2ped. Intra-molecular interactions were analyzed by ‘Atoms in molecule’ (AIM) approach. Computed first static hyperpolarizability (β0 = 8.583 × 10−30 esu) indicates non-linear optical (NLO) response of the molecule. Molecular docking studies show that the title molecule may act as potential acetylcholine esterase (AChE) inhibitor.

English

In vitro micropropagation of banana ( Musa spp.) cv.virupakshi (Hillbanana) was studied. Suckers were collected from the germ plasm block of Jain R&D (originally established from the suckers from Palani Hills, Tamil Nadu) during summer. The sucker surface sterilized with 1% NaOCl for 30 min gave 100% survival without any contamination. Apical meristems that were isolated and cultured on MS based media supplemented with benzylaminopurine (BAP) 10.0 mg/l and IAA1.0 mg/l gave higher number of shoots (134.3 shoots/explant) within168 days (24 weeks). Kinetin 2.0 mg/l and NAA0.5 mg/l gave early rooting in just five days with 6.6 roots per plant. Observations were recorded after every four weeks up to six sub-culturing. Acclimatization was done in poly house, followed by shade house under 50% light conditions. The hardened plants when shifted to the field showed luxurious growth. The regenerated micro propagated banana plants were tested for genetic uniformity through 13 inter simple sequence repeat (ISSR) markers recommended by NCS-TCP, DBT. Profiles obtained by all the three ISSR primers namely, 834, 840 and 850, respectively exhibited similar banding patterns, which revealed the existence of genetic uniformity in micro- propagated plants. Keywords: Micropropagation, Virupakshi, hill banana, banana bunchy top virus

KAJIAN PENGARUH VARIASI KONSENTRASI ASAM SITRAT TERHADAP KEKUATAN GEL PRODUK GELATIN KULIT AYAM BROILER DIKAITKAN DENGAN POLA PROTEINNYA

Gelatin is a biopolymer that can be generated from partially hydrolysis of collagen tissue. Extraction of gelatin consists of pretreatment and thermal extraction steps. Pretreatment process used sodium hydroxide to remove non collagen protein in matrix sample, sulfuric acid to demineralize, and citric acid to hydrolyse. The aim of this research was to study the effect of variation in concentrations of citric acid used in hydrolysis process on the gel strength and protein profile of gelatin products extracted from broiler chicken skin. The variation of the concentration citric acid used was 0.7 % (GA); 1.5% (GB); and 3.0% b/v (GC) respectively. The gel strength was measured using CT3 Texture Analyzer and protein profile of gelatin product was analyzed by SDS-PAGE method. The result showed that variation in concentration of citric acid used in the pretreatment process affected the gel strength and protein profile of gelatin product. Increasing the concentration of citric acid used in pretreatment process decreased the gel strength and molecular weight of gelatin product. Gel strength of each gelatin product was 265.81 g bloom for GA ; 196.05 g bloom for GB (1.5%), and 35.32 g bloom for GC (3.0 %) respectively. The electropherogram of both GA (0.7%) and GB (1.5%) revealed similar pattern of protein bands but the thickness of each bands was different. On the other hands, GC (3.0%) did not show any protein bands on the eletropherogram. The best gelatin product obtained in this experiment was found by using 0.7 % b/v citric acid (GA) in the pretreatment process. The gelatin product (GA) had characteristics as follows: yield 15.73%; moisture 7.30%; ash 0.51%; protein content 97.95%; fat content 0.62%; gel strength 265. 81 g bloom and thicker protein bands than others.

Assessment of cecal microbiota, integron occurrence, fermentation responses, and Salmonella frequency in conventionally raised broilers fed a commercial yeast-based prebiotic compound

Prebiotics are defined as nondigestible food ingredients that can stimulate the growth of one or more beneficial bacteria in the gastrointestinal tract. The Biolex® MB40 is a commercial prebiotic that contains mannanoligosaccharides. The aims of this study were to evaluate the effects of prebiotic Biolex® MB40 on cecal microbiota of conventionally raised chickens using PCR-based denaturing gradient gel electrophoresis (DGGE) and assessing Salmonella prevalence. Chickens were randomly selected and distributed into three groups; a negative control (NC) and two treatment groups (T1 and T2). The NC group was fed a non-medicated feed, while the treatment groups were fed either T1 or T2, 0.05% antibiotic (BMD50) or 0.2% Biolex® MB40 respectively. During the study, cecal contents and bird feed were plated on selective media for Salmonella, yeast and mold prevalence analysis. Ten chickens from each group were randomly selected at 1, 2, 4 and 6 wk and ceca were extracted for DNA isolation for PCR-based DGGE. Also, short-chain fatty acids (SCFAs) were analyzed from collected cecal material by gas chromatography. Only 4.2% of the samples were Salmonella positive. Presence of class 1 integron from cecal material were analyzed by PCR and 97.5% of the cecal samples were positive for integron presence, but no class I integrons were detected in the Salmonella isolates. According to the PCR-based DGGE analysis, the T2 group exhibited a cecal microbial population pattern that was similar to the T1 group prior to wk 4 and the T2 group appeared to be almost identical with the NC group after wk 4 but T2 exhibited less Bacteroides rodentium prior to wk 4. Overall results showed that the commercial prebiotic, MB40 did not lead to a detectable reduction of Salmonella but the general frequency of Salmonella was minimal in all treatments. However, feeding an MB40 supplement did result in similar DGGE band patterns as the T1 group indicating that cecal microbiotia were potentially similar in these 2 groups. Overall, it appears that MB40 (T2) exhibited similar DGGE-cecal population patterns as BMD50 (T1) which suggests that these treatments may have influenced the populations in a comparable fashion.

Establishment of in vitro regeneration from petiole explants and assessment of clonal fidelity by ISSR markers in Luffa acutangula L.Roxb

An improved in vitro organogenesis was achieved from petiole explants of Luffa acutangula L.Roxb, a medicinally and economically important cucurbitaceous member. Morphogenetic response of petiole explants excised from in vitro grown plants has been studied with different concentrations of auxins and cytokinins. Higher percent of callus induction was occurred on Murashige and Skoog (MS) medium supplemented with 2mg/L BAP and 0.2mg/L NAA from the cut ends of petiole explants after 4 weeks of culture. Multiple shoots (8.28±0.85 shoots per explant) were induced after 2-3 weeks from the green compact callus upon on to MS medium with 30g/L sucrose, 2.0mg/L BAP along with 0.2mg/L IAA. The elongation of proliferated shoots was achieved on same medium supplemented additionally with 0.3 mg/L GA3. The elongated shoots (1cm) were rooted on MS medium supplemented with 0.5 mg/L IBA. Rooted plants were acclimatized in the greenhouse and subsequently established in soil with 85% survival rate. Clonal fidelity of in vitro raised plantlets was determined using ISSR marker technique. The results showed the similar banding pattern with different ISSR primers ranging from 250bp to 1000bp and indicated the absence of polymorphism in donar mother plant and as well in in vitro regenerated plants.

Suppression of glypican-1 autodegradation by NO-deprivation correlates with nuclear accumulation of amyloid beta in normal fibroblasts.

Heparan sulfate (HS)-containing, S-nitrosylated (SNO) glypican-1 (Gpc-1) releases anhydromannose-containing HS (anMan-HS) by SNO-catalyzed autodegradation in endosomes. Transport of anMan-HS to the nucleus requires processing of the amyloid precursor protein (APP) to amyloid beta peptides (Aβ). To further examine the relationship between APP and Gpc-1 processing in normal fibroblasts we have suppressed Gpc-1 autodegradation by aminoguanidine inhibition of NO synthesis and prevented lysosomal degradation of anMan-HS by using chloroquine. Deconvolution immunofluorescence microscopy and SDS-PAGE using anMan- and APP/Aβ-specific antibodies and markers for nuclei and autophagosomes were used to identify subcellular localization of Aβ and its oligomeric state. Wild-type mouse embryonic fibroblasts (WT MEF) grown during NO-deprivation accumulated 95-98% of Aβ as oligomers in the nucleus. WT MEF treated with chloroquine accumulated both anMan-HS and Aβ, first in the nucleus then in autophagosomes. Maximal nuclear anMan-HS and Aβ accumulation was obtained after 4 and 7 h of growth, respectively. Both yielded similar banding patterns on SDS-PAGE which were also similar to the Aβ oligomers obtained after NO-deprivation. Nuclear Aβ accumulation was marginally increased (from 54 to 58%) by suppression of both release and degradation of anMan-HS. Nuclear exit of Aβ, accumulated during growth in aminoguanidine, was enhanced by ascorbate-induced reactivation of anMan-HS production. Transgenic Alzheimer disease mouse (Tg2576) MEF, which produces excess amount of Aβ was used for comparison. Overall, nuclear Aβ exit and lysosomal degradation was compromised by inhibition of the autophagosome-lysosome pathway in both WT and Tg2576 MEF, while only WT MEF was sensitive to suppression of Gpc-1 autodegradation.

Developmental ecdysteroid titers and DNA puffs in larvae of two sciarid species, Rhynchosciara americana and Rhynchosciara milleri (Diptera: Sciaridae).

Ecdysteroid titers, developmental landmarks and the presence of prominent amplifying regions (DNA puffs) have been compared during late larval to pupal development in four groups of Rhynchosciara americana larvae and in R. americana and Rhynchosciara milleri. Three prominent DNA puffs (B2, C3 and C8) expand and regress sequentially on the rising phase of the 20-hydroxyecdysone (20E) titer in R. americana as a firm, cellular cocoon is being constructed. A sharp rise in 20E coincides with the regression of these puffs. The shape of the 20E curve is similar in R. milleri, a species that does not construct a massive cocoon, but the behavior of certain DNA puffs and their temporal relationship to the curve differs. Regions corresponding to B2 and C3 can be identified in R. milleri by banding pattern similarity with R. americana chromosomes and, in the case of B2, by hybridization to an R. americana probe. A B2 puff appears in R. milleri as the 20E titer rises but remains small in all gland regions. A puff similar to the R. americana C3 puff occurs in posterior gland cells of R. milleri (C3(Rm)) after the B2 puff, but this site did not hybridize to R. americana C3 probes. C3(Rm) incorporated (3)H-thymidine above background, but showed less post-puff DNA accumulation than C3 of R. americana. R. americana C8 probes hybridized to a more distal region of the R. milleri C chromosome that did not appear to amplify or form a large puff. These differences can be related to developmental differences, in particular differences in cocoon construction between the two species.

Take-all decline in New Zealand wheat soils and the microorganisms associated with the potential mechanisms of disease suppression

Take-all, caused by the soilborne pathogen Gaeumannomyces graminis var. tritici, (Ggt), is an important root disease of wheat. Continuous wheat cropping has been shown to induce take-all decline (TAD). This research investigated the mechanisms of TAD in 13 New Zealand soils in two experiments and identified the associated microorganisms using denaturing gradient gel electrophoresis (DGGE). In Experiment 1, a sterile sand/maize-meal mixture inoculated or not inoculated with Ggt, was added at 4 % (w/w) to sterilised and non-sterilised soils to determine their ability to suppress take-all, and to help identify the nature of suppression. Experiment 2 investigated the transferability of suppressive properties in five of the soils from Experiment 1. The microbial communities of these five soils were analysed using PCR-DGGE. Ten of the soils were able to suppress take-all but the suppression was biological in nature in only four of these soils. The suppressive properties of two of the soils were transferred to a γ-irradiated base soil amended with Ggt, indicating that suppression could be specific in nature (i.e., attributed to a specific microorganism or group of microorganisms). The suppressive properties in one soil were not transferrable, suggesting a general form of suppression, most probably because the conditions in the soil were suitable for other microorganisms to compete with Ggt. DGGE analyses of the microbial communities for five of the soils showed similar banding patterns for those with similar forms of suppression (specific, general and non-suppressive) and identified the potential microorganisms that distinguished them. These distinguishing microorganisms are likely to independently or interactively have a function in suppressing take-all.

Characterization and genetic variability of feed-borne and clinical animal/human Aspergillus fumigatus strains using molecular markers.

Aspergillus fumigatus, the major etiological agent of human and animal aspergillosis, is a toxigenic fungus largely regarded as a single species by macroscopic and microscopic features. However, molecular studies have demonstrated that several morphologically identified A. fumigatus strains might be genetically distinct. This work was aimed to apply PCR-restriction length fragment polymorphisms (PCR-RFLP) and random amplification of polymorphic DNA (RAPD) molecular markers to characterize a set of feed-borne and clinical A. fumigatus sensu lato strains isolated from Argentina and Brazil and to determine and compare their genetic variability. All A. fumigatus strains had the same band profile and those typical of A. fumigatus sensu stricto positive controls by PCR-RFLP. Moreover, all Argentinian and Brazilian strains typified by RAPD showed similar band patterns to each other and to A. fumigatus sensu stricto reference strains regardless of their isolation source (animal feeds or human/animal clinical cases) and geographic origin. Genetic similarity coefficients ranged from 0.61 to 1.00, but almost all isolates showed 78% of genetic similarly suggesting that genetic variability was found at intraspecific level. Finally, benA sequencing confirmed its identification as A. fumigatus sensu stricto species. These results suggest that A. fumigatus sensu stricto is a predominant species into Aspergillus section Fumigati found in animal environments as well as in human/animal clinical cases, while other species may be rarely isolated. The strains involved in human and animal aspergillosis could come from the environment where this fungus is frequently found. Rural workers and animals would be constantly exposed.