Identification of Fungi Involved in Onychomycosis in Patients of a Spanish Rural Area.

Onychomycosis is one of the most frequent reasons for visiting podiatrist clinics. Complementary tests and the accurate identification of the infectious agents are key issues for a successful treatment of onychomycosis. This is particularly important when lifestyle, age and immunodepressed patients increase the prevalence of non-dermatophyte fungal infection. In this paper, we describe issues related to onychomycosis prevalence in a population of patients, mostly with rural lifestyles, visiting a podiatry clinic in a rural area of Spain. A total of 51 cases were studied with an average age of 65.96 ± 21.28 years (the youngest being 16 years and the oldest being 95 years). Fungal agents were isolated using conventional sampling and microbiological culture techniques. The results obtained with these techniques were compared with the results obtained with a direct methodology using molecular biology, by PCR and nucleotide sequencing of the ITS-5.8S rDNA fragment. The classical culture methodology confirmed the infection in 76.5% of the samples (n = 39), while the PCR confirmed the infection in 84.3% (n = 51) of the nails, although the difference between these results did not show statistical significance (p = 0.388). We found a high variability in agents, with more yeasts than dermatophytes as etiological agents of onychomycosis. However, only among individuals older than 65 years, was the difference between yeasts (82%) and dermatophytes (18%) was statistically significant (p = 0.004). Among the agents of non-dermatophyte onychomycosis, we found predominantly fungi (yeasts) of the Candida genus, interestingly with no isolates of Candida albicans, and moulds of the Aspergillus genus.

Importance of Footwear for Preventing Xerosis and Hyperkeratosis in Older People with Psychiatric Disorders Living in an Institution.

Few studies have focused on the relation between the use and characteristics of footwear and the presence of foot lesions in people with psychiatric disorders. This work analyzes the influence of different footwear habits on the presence of deformities and ungueal and dermal pathologies of the foot of institutionalized people with psychiatric disorders compared to people without these disorders. A transversal and observational study was conducted on 107 participants, divided into two groups who have used different types of shoes throughout their lives. The control group comprised 63 autonomous people who mainly use leather footwear and a study group of 44 institutionalized people with intellectual disabilities and psychiatric disorders who mainly use textile footwear. There were significant differences between populations. The group with psychiatric disorders presented more xerosis and hyperkeratosis. Footwear with inappropriate characteristics is a possible causal agent of skin alterations. Wearing footwear with quality textile uppers, e.g., fabric or felt, could influence the appearance of these alterations. Leather footwear is recommended for institutionalized people to reduce symptoms of xerosis and improve their quality of life.

Mutations in Novel Lipopolysaccharide Biogenesis Genes Confer Resistance to Amoebal Grazing in Synechococcus elongatus.

In natural and artificial aquatic environments, population structures and dynamics of photosynthetic microbes are heavily influenced by the grazing activity of protistan predators. Understanding the molecular factors that affect predation is critical for controlling toxic cyanobacterial blooms and maintaining cyanobacterial biomass production ponds for generating biofuels and other bioproducts. We previously demonstrated that impairment of the synthesis or transport of the O-antigen component of lipopolysaccharide (LPS) enables resistance to amoebal grazing in the model predator-prey system consisting of the heterolobosean amoeba HGG1 and the cyanobacterium Synechococcus elongates PCC 7942 (R. S. Simkovsky et al., Proc Natl Acad Sci U S A 109:16678-16683, 2012,http://dx.doi.org/10.1073/pnas.1214904109). In this study, we used this model system to identify additional gene products involved in the synthesis of O antigen, the ligation of O antigen to the lipid A-core conjugated molecule (including a novel ligase gene), the generation of GDP-fucose, and the incorporation of sugars into the lipid A core oligosaccharide ofS. elongatus Knockout of any of these genes enables resistance to HGG1, and of these, only disruption of the genes involved in synthesis or incorporation of GDP-fucose into the lipid A-core molecule impairs growth. Because these LPS synthesis genes are well conserved across the diverse range of cyanobacteria, they enable a broader understanding of the structure and synthesis of cyanobacterial LPS and represent mutational targets for generating resistance to amoebal grazers in novel biomass production strains.

Analysis, quantification, and evolutionary consequences of HIV-1 in vitro recombination.

HIV-1 recombination was studied in vitro by viral cocultivation of four combinations of strains of subtypes B, D, and F. Viral cocultivations were performed in MT-4 cells and maintained for 22 days. The parental and recombinant forms were quantified by a specific PCR system in an env fragment of 2500 nucleotides. On day 5, there was a close correlation between the proportion of recombination and the genetic distance between strains. In three of the four viral combinations studied, a steady increase in the proportion of recombinant genomes was observed over time. This rise coincided with the progressive loss of one of the parental strains, resulting in less diverse viral populations. Nucleotide sequencing of biological recombinant clones from the B/D cocultivation revealed a higher number of recombination events in pol than in env gene, and an increasing number of crossovers per clone with time.