Differential gene expression revealed with RNA-Seq and parallel genotype selection of the ornithine decarboxylase gene in fish inhabiting polluted areas.

How organisms adapt to unfavorable environmental conditions by means of plasticity or selection of favorable genetic variants is a central issue in evolutionary biology. In the Maipo River basin, the fish Basilichthys microlepidotus inhabits polluted and non-polluted areas. Previous studies have suggested that directional selection drives genomic divergence between these areas in 4% of Amplified Fragment Length Polymorphism (AFLP) loci, but the underlying genes and functions remain unknown. We hypothesized that B. microlepidotus in this basin has plastic and/or genetic responses to these conditions. Using RNA-Seq, we identified differentially expressed genes in individuals from two polluted sites compared with fish inhabiting non-polluted sites. In one polluted site, the main upregulated genes were related to cellular proliferation as well as suppression and progression of tumors, while biological processes and molecular functions involved in apoptotic processes were overrepresented in the upregulated genes of the second polluted site. The ornithine decarboxylase gene (related to tumor promotion and progression), which was overexpressed in both polluted sites, was sequenced, and a parallel pattern of a heterozygote deficiency and increase of the same homozygote genotype in both polluted sites compared with fish inhabiting the non-polluted sites was detected. These results suggest the occurrence of both a plastic response in gene expression and an interplay between phenotypic change and genotypic selection in the face of anthropogenic pollution.

Advanced Inorganic Nanosystems for Skin Drug Delivery.

On/into/through the skin drug delivery represents an attractive alternative for the oral route, providing local and/or systemic drug delivery. Due to its complex and well-organised structure, most of the drugs show difficulties to penetrate the human skin. Therefore, enormous efforts have been invested to develop intelligent drug delivery systems overcoming the skin barrier with particular emphasis on increasing therapeutic activity and minimizing undesirable side-effects. Most of these strategies require the use of singular materials with new properties. In particular, and on the basis of their inherent properties, including biocompatibility, biodegradability and relative low-cost, inorganic nanoparticles are ideal candidates for the development of skin drug delivery systems. This review provides an updated and comprehensive overview of the state of the art in the trends towards skin drug delivery with a particular focus in the attractive alternative offered by inorganic-based nanosystems.

Assessment of halloysite nanotubes as vehicles of isoniazid.

Equilibrium and thermodynamic aspects of the adsorption of isoniazid (INH) onto halloysite nanotubes (HLNTs) and characteristics of the resultant drug/nanocarrier systems are investigated. Equilibrium studies were performed in aqueous medium at different times, temperatures and drug concentrations. The overall adsorption process was explained as the result of two simple processes: adsorption on the activated sites of HLNTs and precipitation of INH on HLNTs surface. Formation of the INH-loaded HLNTs was spontaneous, endothermic and endoentropic, increasing the thermodynamic stability of the system (ΔH=70.40kJ/mol; ΔS=0.2519kJ/molK). Solid state characterization corroborated the effective interaction between the components that was also described by modeling at molecular level by quantum mechanics calculations along with empirical interatomic potentials. Transmission electron microphotographs confirmed the double allocation and homogeneous distribution of INH in the nanohybrids. FTIR spectra revealed the interaction via hydrogen bonds between the inner hydroxyl groups of HLNTs and N in INH molecules. Loading of INH in the nanohybrids was approximately 20% w/w. Effective loading of INH and activation energies of the interactions enable to propose the designed nanohybrids in the development of modified drug delivery systems.

Release kinetics of 5-aminosalicylic acid from halloysite.

This paper investigates desorption of 5-aminosalicilyc acid (5-ASA) adsorbed onto halloysite (HL). Desorption isotherms were fitted according to kinetic laws obtained considering release of 5-ASA from HL as the phase of desorption of the previously adsorbed drug molecules both inside the nanotubes of HL as onto the surface of clay particles and/or in the inter-particle spaces of their aggregates. Desorption isotherms has been also fitted with other equations frequently used in drug release kinetics studies. The best fitting corresponded to the kinetic model proposed; in agreement with the results of adsorption.

Diversity of Flavobacterium psychrophilum and the potential use of its phages for protection against bacterial cold water disease in salmonids.

Flavobacterium psychrophilum causes rainbow trout fry syndrome (RTFS) and cold water disease (CWD) in salmonid aquaculture. We report characterization of F. psychrophilum strains and their bacteriophages isolated in Chilean salmonid aquaculture. Results suggest that under laboratory conditions phages can decrease mortality of salmonids from infection by their F. psychrophilum host strain. Twelve F. psychrophilum isolates were characterized, with DNA restriction patterns showing low diversity between strains despite their being obtained from different salmonid production sites and from different tissues. We isolated 15 bacteriophages able to infect some of the F. psychrophilum isolates and characterized six of them in detail. DNA genome sizes were close to 50 Kbp and corresponded to the Siphoviridae and Podoviridae families. One isolate, 6H, probably contains lipids as an essential virion component, based on its chloroform sensitivity and low buoyant density in CsCl. Each phage isolate rarely infected F. psychrophilum strains other than the strain used for its enrichment and isolation. Some bacteriophages could decrease mortality from intraperitoneal injection of its host strain when added together with the bacteria in a ratio of 10 plaque-forming units per colony-forming unit. While we recognize the artificial laboratory conditions used for these protection assays, this work is the first to demonstrate that phages might be able protect salmonids from RTFS or CWD.

Molecular analysis of microbiota along the digestive tract of juvenile Atlantic salmon (Salmo salar L.).

Dominant bacterial microbiota of the gut of juvenile farmed Atlantic salmon was investigated using a combination of molecular approaches. Bacterial community composition from the stomach, the pyloric caeca, and the intestine was assessed by extracting DNA directly from each gut compartment. Temporal temperature gradient gel electrophoresis (TTGE) analysis of 16S ribosomal DNA (rDNA) amplicons showed very similar bacterial compositions throughout the digestive tract. Band sequencing revealed a narrow diversity of species with a dominance of Pseudomonas in the three compartments. However, cloning revealed more diversity among the Pseudomonas sequences. To confirm these results, we analyzed the bacterial community by amplifying the variable 16S-23S rDNA intergenic spacer region (ITS). Similar ITS profiles were observed among gastrointestinal compartments of salmon, confirming the TTGE results. Moreover, the dominant ITS band at 650 bp, identified as Pseudomonas, was observed in the ITS profile from fish collected in two seasons (July 2003 and 2004). In contrast, aerobic culture analysis revealed Shewanella spp. as the most prevalent isolate. This discrepancy was resolved by evaluating 16S rDNA and ITS polymerase chain reaction amplification efficiency from both Shewanella and Pseudomonas isolates. Very similar efficiencies were observed in the two bacteria. Hence, this discrepancy may be explained by preferential cultivation of Shewanella spp. under the experimental conditions. Also, we included analyses of pelleted feed and the water influent to explore environmental influences on the bacterial composition of the gut microbiota. Overall, these results indicate a homogeneous composition of the bacterial community composition along the gastrointestinal tract of reared juvenile salmon. This community is mainly composed of Pseudomonas spp., which could be derived from water influent and may be selectively associated with salmon in this hatchery.

Linfoma hepático primario. Evolución favorable con quimioterapia combinada con rituximab / No disponible

Comunicamos el caso de una paciente con un linfoma hepáticoprimario tratado con éxito con quimioterapia combinada conrituximab. Utilizando los “encabezamientos estándar para búsquedasbibliográficas informatizadas” (Medical Subject Heading) revisamoslos casos publicados hasta la fecha de esta infrecuenteentidad

This article describes the case of a patient with a non-Hodgkinprimary hepatic lymphoma who was successfully treated withchemotherapy combined with rituximab. Using the Medical Subject Headings the published reports of this rare entity were reviewed (AU)

[Primary hepatic lymphoma - favorable outcome with chemotherapy plus rituximab]. / Linfoma hepático primario. Evolución favorable con quimioterapia combinada con rituximab.

This article describes the case of a patient with a non-Hodgkin primary hepatic lymphoma who was successfully treated with chemotherapy combined with rituximab. Using the Medical Subject Headings the published reports of this rare entity were reviewed.

Varón de 75 años con atelectasia del lóbulo medio / 75 year old man with middle lobe atelectasis

No disponible

The role of pollen in chalkbrood disease in Apis mellifera: transmission and predisposing conditions.

Chalkbrood in honeybees (Apis mellifera L. Himenoptera: Apidae) is a fungal disease caused by Ascosphaera apis (Maassen ex Claussen) Olive and Spiltoir. This disease requires the presence of fungal spores and a predisposing condition in the susceptible brood for the disease to develop. In this study we examined the role of pollen in the development of chalkbrood disease under two experimental conditions: (i) pollen combs were transferred from infected to uninfected beehives and (ii) colonies were deprived of adequate pollen supplies to feed the brood. The results of both treatments confirmed that pollen is an element that should be taken into account when controlling this honeybee disease.

Bacterial 16S rRNA gene analysis revealed that bacteria related to Arcobacter spp. constitute an abundant and common component of the oyster microbiota (Tiostrea chilensis).

To explore the bacterial microbiota in Chilean oyster (Tiostrea chilensis), a molecular approach that permits detection of different bacteria, independently of their capacity to grow in culture media, was used. Bacterial diversity was assessed by analysis of both the 16S rDNA and the 16S-23S intergenic region, obtained by PCR amplifications of DNA extracted from depurated oysters. RFLP of the PCR amplified 16S rDNA showed a prevailing pattern in most of the individuals analyzed, indicating that a few bacterial species were relatively abundant and common in oysters. Cloning and sequencing of the 16S rDNA with the prevailing RFLP pattern indicated that this rRNA was most closely related to Arcobacter spp. However, analysis by the size of the amplified 16S-23S rRNA intergenic regions revealed not Arcobacter spp. but Staphylococcus spp. related bacteria as a major and common component in oyster. These different results may be caused by the absence of target for one of the primers employed for amplification of the intergenic region. Neither of the two bacteria species found in large abundance was recovered after culturing under aerobic, anaerobic, or microaerophilic conditions. This result, however, is expected because the number of bacteria recovered after cultivation was less than 0.01% of the total. All together, these observations suggest that Arcobacter-related strains are probably abundant and common in the Chilean oyster bacterial microbiota.

Insuficiencia de venas perforantes en miembros inferiores. ligadura subfascial endoscópica / Incompetent perforating veins in the lower extremities. Endoscopic subfascial ligature

El papel de las venas perforantes incompetentes en la enfermedad venosa crónica está bien establecido. La localización de las venas perforantes y la valoración de su alteración hemodinámica se realizó mediante exploración clínica y eco-Doppler. De 1999 a 2000, 50 pacientes diagnosticados de insuficiencia de venas perforantes fueron sometidos a ligadura subfascial endoscópica de venas perforantes incompetentes, con o sin safenectomía por stripping. La ligadura subfascial permite la curación de las úlceras venosas y la drástica reducción de la tasa de recurrencia de las mismas, así como una rápida curación de las heridas quirúrgicas y un buen resultado estético. (AU)

Expression of cathepsins B, L, S, and D by gastric epithelial cells implicates them as antigen presenting cells in local immune responses.

Helicobacter pylori infection is linked to chronic gastritis, peptic ulcer and gastric carcinoma. During H. pylori infection, class II MHC expression by the gastric epithelium increases, as does the number of local CD4(+) T cells, which appear to be important in the associated pathogenesis. These observations suggested that the epithelium might present antigens to T cells. Thus, we sought to determine whether gastric epithelial cells process antigens to establish their function as local antigen presenting cells (APC). We examined a panel of gastric epithelial cell lines for expression of the antigen processing cathepsins B (CB), L (CL), S (CS), and D (CD). The mRNA for these enzymes were detected by RT-PCR and the enzymes in the gastric epithelial cells were identified by various independent methods. We corroborated the expression of CB and CD on gastric epithelial cells from human biopsy samples. The functions of these proteases were confirmed by assessing their ability to digest ovalbumin, a conventional dietary antigen, and proteins from H. pylori. In summary, multiple lines of evidence suggest gastric epithelial cells process antigens for presentation to CD4(+) T cells. To our knowledge, these are the first studies to document the antigen processing capacity of human gastric epithelial cells.

[Treatment of non-parasitic splenic cyst with percutaneous injection of alcohol]. / Tratamiento del quiste esplénico no parasitario con inyección percutánea de alcohol.

We report a case of a 12-years-old girl treated by percuta-neous injection of a splenic epithelial cyst. Indication was due to the gradual cyst's growth and pain in left hypocondrium. A percutaneous drainage under ultrasonographic view was performed with direct puncture technique, inserting a pigtail catheter into the cyst. After the total aspiration of the contrast, we injected sterile absolute alcohol for 20 minutes. Subsecuently, it was aspirated and the catheter was pulled-out. After a follow up period of more than 4 years, the cyst remains collapsed. There were no complications.

Helicobacter pylori urease binds to class II MHC on gastric epithelial cells and induces their apoptosis.

Infection by Helicobacter pylori leads to injury of the gastric epithelium and a cellular infiltrate that includes CD4+ T cells. H. pylori binds to class II MHC molecules on gastric epithelial cells and induces their apoptosis. Because urease is an abundant protein expressed by H. pylori, we examined whether it had the ability to bind class II MHC and induce apoptosis in class II MHC-bearing cells. Flow cytometry revealed the binding of PE-conjugated urease to class II MHC+ gastric epithelial cell lines. The binding of urease to human gastric epithelial cells was reduced by anti-class II MHC Abs and by staphylococcal enterotoxin B. The binding of urease to class II MHC was confirmed when urease bound to HLA-DR1-transfected COS-1 (1D12) cells but not to untransfected COS-1 cells. Urease also bound to a panel of B cell lines expressing various class II MHC alleles. Recombinant urease induced apoptosis in gastric epithelial cells that express class II MHC molecules, but not in class II MHC- cells. Also, Fab from anti-class II MHC and not from isotype control Abs blocked the induction of apoptosis by urease in a concentration-dependent manner. The adhesin properties of urease might point to a novel and important role of H. pylori urease in the pathogenesis of H. pylori infection.

Bacterial community in copper sulfide ores inoculated and leached with solution from a commercial-scale copper leaching plant.

Most copper bioleaching plants operate with a high concentration of sulfate salts caused by the continuous addition of sulfuric acid and the recycling of the leaching solution. Since the bacteria involved in bioleaching have been generally isolated at low sulfate concentrations, the bacterial population in ores leached with the high-sulfate solution (1.25 M) employed in a copper production plant was investigated. The complexity of the original population was assessed by the length pattern of the spacer regions between the 16S and 23S rRNA genes, observed after PCR amplification of the DNA extracted from the leached ore. Six main spacers were distinguished by electrophoretic migration, but they could be further resolved into eight spacers by nucleotide sequence homology. The degree of homology was inferred from the electrophoretic migration of the heteroduplexes formed after hybridization. One of the spacers was indistinguishable from that found in Thiobacillus thiooxidans, four could be related to Thiobacillus ferrooxidans, and three could be related to Leptospirillum ferrooxidans. Only five of the spacers in the original sample could be recovered after culturing in media containing different inorganic energy source. Altogether, the results indicate that the bacteria in the leached ore formed a community composed of at least three species: a fairly homogeneous population of T. thiooxidans strains and two heterogeneous populations of T. ferrooxidans and L. ferrooxidans strains.

Chemolithotrophic bacteria in copper ores leached at high sulfuric Acid concentration.

Extensive bacterial growth was observed when copper sulfide ores were leached with 0.6 N sulfuric acid. The bacterial population developed in this condition was examined by characterization of the spacer regions between the 16S and 23S rRNA genetic loci obtained after PCR amplification of the DNA extracted from the leached ore. The spacers observed had the sizes found in strains of "Leptospirillum ferrooxidans" and Thiobacillus thiooxidans, except for a larger one, approximately 560 bp long, that was not observed in any of the strains examined, including those of Thiobacillus ferrooxidans. The bacteria with this last spacer were selected after culturing in mineral and elemental sulfur media containing 0.7 N sulfuric acid. The spacer and the 16S ribosomal DNA of this isolate were sequenced and compared with those in species commonly found in bioleaching processes. Though the nucleotide sequence of the spacer showed an extensive heterologous region with T. thiooxidans, the sequence of its 16S rDNA gene indicated a close relationship (99.85%) with this species. These results indicate that a population comprised of bacterial strains closely related to T. thiooxidans and of another strain, possibly related to "L. ferrooxidans," can develop during leaching at high sulfuric acid concentration. Iron oxidation in this condition is attributable to "L. ferrooxidans" and not T. ferrooxidans, based on the presence of spacers with the "L. ferrooxidans" size range and the absence of spacers characteristic of T. ferrooxidans.

Eficacia de la asociación metoclopramida diazepamdimeticona en el sindrome dispéptico funcional (SDF). Estudio clínico randomizado controlado con placebo / Association efficacy of metoclopramide-diazepam-dimeticone in non-ulcer functional dyspepsia. Controlled clinical trial

Se estudiaron 104 pacientes ambulatorios con SDF no ulceroso, en fase sintomática, randomizados en dos grupos homogéneos:medicamento (48), placebo (56). El presente ensayo evalúa la eficacia de la asociación farmacológica de metoclopramida (5mg), diazepam (2.5mg)y dimeticona (100 mg) frente al placebo en el SDF de tipo no ulceroso, así como la tolerancia y efectos colaterales de la asociación. Luego de una apreciación inicial se realizó el seguimiento de ambos grupos durante 21 días, evaluándose:naúsea, llenura postprandial, ardor epigástrico, dolor vago, eructación, y balonamiento, y la impresión final del médico y del paciente. Todos los parámetros evaluados fueron ampliamente favorables para la asociación medicamentosa, siendo la diferencia estadísticamente significativa en el caso náusea, llenura postprandial y ardor epigástrico. La tolerancia en ambos grupos fue buena y como efectos colaterales adversos sólo cabe consignar una mayor somnolencia en el grupo medicamento, que fue mínima.