Experiencia sobre el proceso de salud-enfermedad-atención en pacientes con artritis reumatoidea pertenecientes a la comunidad Wichí de Misión Chaqueña "El Algarrobal", Salta / Experience on the health-disease-care process in patients with rheumatoid arthritis belonging to the Wichí community of Mission Chaqueña "El Algarrobal", Salta

Introducción: se ha reportado que la prevalencia de artritis reumatoidea (AR) en la comunidad Wichí representa la más alta informada por el Grupo Latinoamericano para el Estudio de las Enfermedades Reumáticas en los Pueblos Originarios (GLADERPO). El objetivo de este estudio fue describir la experiencia sobre el proceso de salud-enfermedad-atención de pacientes con AR de la comunidad Wichí de Misión Chaqueña "El Algarrobal", Salta. Materiales y métodos: estudio narrativo. Diseño de corte etnográfico. Se realizaron entrevistas semi-estructuradas y observaciones registradas. Se utilizaron guías de entrevistas y observación. Los aspectos incluidos fueron: concepción del proceso salud-enfermedad, percepción de la AR en la vida diaria, el acceso al sistema de salud, utilización de recursos tradicionales y de medicina tradicional. Resultados: se realizaron 10 entrevistas. Los aspectos más relevantes fueron la concepción del proceso salud-enfermedad asociado al trauma social pasado y al concepto de voluntad Wichí. Se evidenció la combinación de estrategias para mejorar el dolor (biomedicina, medicina tradicional y acompañamiento religioso). Además, se observó una relación unidireccional con el sistema de salud. Conclusiones: la AR es una enfermedad con un impacto negativo en la comunidad Wichí. Se requieren otras actividades, desde otras disciplinas, para mejorar el acceso al sistema de salud y la continuidad de los tratamientos.

Introduction: the prevalence of rheumatoid arthritis (RA) in the Wichí community has already been published, representing the highest reported by the Grupo Latinoamericano para el Estudio de las Enfermedades Reumáticas en los Pueblos Originarios (GLADERPO). The objective was to describe the experience of the health-disease-care process of patients with RA from the Wichí community of Misión Chaqueña "El Algarrobal", Salta. Materials and methods: study with ethnographic design. Semi-structured interviews and recorded observations were conducted. Interview and observation guides were used. The aspects included were: conception of the health-disease process; perception of RA in daily life, access to the health system, use of traditional resources and traditional medicine. Results: ten interviews were conducted. The most relevant aspects were the conception of the health-disease process, associated with past social trauma and the concept of "Wichí good will". The combination of strategies to improve pain (biomedicine, traditional medicine and religious accompaniment) was evidenced. In addition, a unidirectional relationship with the health system was observed. Conclusions: RA is a disease with a negative impact on the Wichí community. Other activities from other disciplines are necessary to improve access to the health system and continuity of treatment.

Prevalence of musculoskeletal disorders and rheumatic diseases in an Argentinean indigenous Wichi community.

OBJECTIVE: To estimate the prevalence of musculoskeletal disorders (MSK) and rheumatic diseases in an indigenous Wichi population in Argentina. METHODS: This is a cross-sectional, community-based study using the Community-Oriented Program for the Control of Rheumatic Diseases (COPCORD) methodology in ≥ 18-year-old subjects. Validated surveys were conducted by trained interviewers. Subjects with MSK pain (positive cases) were evaluated by internists and rheumatologists for diagnosis and treatment. RESULTS: A total of 648 interviews were performed (90.4% of the census population). Mean age was 37.5 years (SD 14.8), and 379 (58.5%) were female. The mean years of education was 7.0 (SD 3.7); 552 subjects (85.2%) were covered by the public health care system. A total of 216 (33.3%) subjects had MSK pain in the last 7 days. Rheumatic disease prevalence was as follows: mechanical back pain (19.0%), rheumatic regional pain syndrome (5.2%), osteoarthritis (3.2%), rheumatoid arthritis (RA) (3.2%), inflammatory back pain (1.2%), undifferentiated arthritis (0.3%), Sjögren syndrome (0.15%), and fibromyalgia (0.15%). RA patients included 19 (90.5%) women and 9 (42.9%) with RA family history. One hundred percent were seropositive and 66.7% showed radiologic erosions. The mean of Disease Activity Score [DAS-28 (ESR)] at the time of diagnosis was 5.1 (SD 1.5) and the Health Assessment Questionnaire Disability Index (HAQ-DI) was 0.8 (SD 0.4). CONCLUSION: RA prevalence was 3.2%, one of the highest reported using the COPCORD methodology in indigenous and non-indigenous peoples in Latin America, with a high percentage of family cases. Pain and functional capacity were the variables allowing patients' early referral to a specialist. Key Points • The RA prevalence was 3.2%, one of the highest reported using COPCORD methodology in indigenous and non-indigenous peoples in Latin America. • The patients with RA had high percentage of familiar history of RA. • The pain and functional capacity were the variables associated with a diagnosis of any rheumatic disease and should be considered for early referral. • The mean of the delay in the diagnosis was 5.8 years. In this community, the lack of the "migration health" phenomenon may be a social determinant that negatively impacts their health.

A Simple Polymicrobial Biofilm Keratinocyte Colonization Model for Exploring Interactions Between Commensals, Pathogens and Antimicrobials.

Skin offers protection against external insults, with the skin microbiota playing a crucial defensive role against pathogens that gain access when the skin barrier is breached. Linkages between skin microbes, biofilms and disease have not been well established although single-species biofilm formation by skin microbiota in vitro has been extensively studied. Consequently, the purpose of this work was to optimize and validate a simple polymicrobial biofilm keratinocyte model for investigating commensal, pathogen and keratinocyte interactions and for evaluating therapeutic agents or health promoting interventions. The model incorporates the commensals (Staphylococcus epidermidis and Micrococcus luteus) and pathogens (Staphylococcus aureus and Pseudomonas aeruginosa) which form robust polymicrobial biofilms on immortalized keratinocytes (HaCat cells). We observed that the commensals reduce the damage caused to the keratinocyte monolayer by either pathogen. When the commensals were combined with P. aeruginosa and S. aureus, much thinner biofilms were observed than those formed by the pathogens alone. When P. aeruginosa was inoculated with S. epidermidis in the presence or absence of M. luteus, the commensals formed a layer between the keratinocytes and pathogen. Although S. aureus completely inhibited the growth of M. luteus in dual-species biofilms, inclusion of S. epidermidis in triple or quadruple species biofilms, enabled M. luteus to retain viability. Using this polymicrobial biofilm keratinocyte model, we demonstrate that a quorum sensing (QS) deficient S. aureus agr mutant, in contrast to the parent, failed to damage the keratinocyte monolayer unless supplied with the exogenous cognate autoinducing peptide. In addition, we show that treatment of the polymicrobial keratinocyte model with nanoparticles containing an inhibitor of the PQS QS system reduced biofilm thickness and P. aeruginosa localization in mono- and polymicrobial biofilms.

Notch Signaling Controls Transcription via the Recruitment of RUNX1 and MYB to Enhancers during T Cell Development.

Tcrd and Tcrg display identical developmental programs that depend on the activity of the enhancers Eδ and Eγ being "on" in pre-ß-selection thymocytes to activate transcription and V(D)J recombination of the unrearranged genes and "off" in post-ß-selection CD4+CD8+ double-positive thymocytes to inhibit transcription of the rearranged genes and avoid the expression of TCR δ- and TCR γ-chains in αß T lymphocytes. Eδ and Eγ activity depends on transcription factor binding to essential Runx and Myb sites and parallels that of Notch signaling. We performed Notch gain- and loss-of-function experiments and found that Notch signaling activates Tcrd and Tcrg transcription by favoring the recruitment of RUNX1 and MYB to the enhancers. Our results suggest that the dissociation of RUNX1 and MYB from Eδ and Eγ chromatin in double-positive thymocytes, which results in enhancer inactivation, is caused by decreased Notch signaling triggered by pre-TCR signaling, thereby deciphering the molecular mechanism of Tcrd and Tcrg silencing during ß-selection. These findings reveal a novel molecular mechanism for gene regulation via Notch signaling through the recruitment of RUNX1 and MYB to enhancer chromatin during thymocyte development.

The Quorum Sensing System of Yersinia enterocolitica 8081 Regulates Swimming Motility, Host Cell Attachment, and Virulence Plasmid Maintenance.

Although Yersinia enterocolitica genomes are highly heterogeneous, they contain a conserved N-acylhomoserine lactone-dependent (AHL) quorum sensing (QS) system consisting of the luxR and luxI orthologs yenR and yenI respectively. Certain hypervirulent strains also contain a putative orphan luxR gene, ycoR, that is not linked to an AHL synthase. To explore the contribution of yenR/yenI/ycoR to QS-dependent phenotypes in Yersinia enterocolitica strain 8081, single and multiple mutants were constructed. AHL profiling identified N-(3-oxohexanoyl) homoserine lactone, N-hexanoylhomoserine lactone, and N-(3-oxoseptanoyl) homoserine lactone as the most abundant. The AHL profiles of the yenR, ycoR and yenR/ycoR mutants were similar to the parent suggesting that the two LuxR homologues do not regulate AHL production while the yenI mutants were AHL-negative. A role for QS in swimming motility and cell attachment was demonstrated. Down-regulation of the virulence plasmid partition gene, spyA, in yenI and yenI/yenR/ycoR mutants is consistent with the greater loss of the Y. enterocolitica pYVe virulence plasmid in the yenI mutant during serial passage at 37 °C but not at 22 °C. A role for QS-regulated spyA in virulence plasmid maintenance is suggested.

Rheumatoid arthritis in the indigenous qom population of Rosario, Argentina: aggressive and disabling disease with inadequate adherence to treatment in a community-based cohort study.

To describe the baseline and follow up epidemiological/clinical characteristics of rheumatoid arthritis (RA) in a community-based cohort of the qom population. RA (ACR criteria) patients identified (n = 40) or not (n = 25) in the previous study were included. Baseline and follow-up visits (3, 6, and 12 months) were performed. Treatment adherence and modification, disability (Health Assessment Questionnaire Disability Index-HAQ-DI), and Disease Activity [DAS-28 (ESR)] were ascertained. At 12 months, complete and incomplete lost to follow-up patients were identified. The estimated RA prevalence was 3%. The patients' mean (SD) disease duration was 110.5 (17.9) and their median delay in diagnosis 30.4 (IQR 52.8) months; mean (SD) age and years of formal education were 39.8 (1.6) and 5.3 (SD 0.3); 58 (89.2%) were female, and 89.2% were seropositive. At baseline, their mean DAS-28 (ESR) was 4.8 (SD 0.9) with 67.7% having high disease activity and 32.3% moderate; 76.9% reported HAQ-DI ≥ 0.8. At 12 months, three patients have died; 13 (20.9%) were "completely" and 19 (30.6%) "incompletely" lost to follow-up. There were favorable changes over time for disease activity (p Ë‚ 0.001), HAQ-DI (p Ë‚ 0.001), and treatment modifications (p Ë‚ 0.001) but no changes in treatment adherence (p = 0.260). The main cause of lost to follow-up was migration. This population has one of the highest RA prevalence rate reported. Patients had an aggressive and disabling disease, with poor adherence to treatment. Improvements of clinical parameters over time were observed.

Identification of a Chemoreceptor in Pseudomonas aeruginosa That Specifically Mediates Chemotaxis Toward α-Ketoglutarate.

Pseudomonas aeruginosa is an ubiquitous pathogen able to infect humans, animals, and plants. Chemotaxis was found to be associated with the virulence of this and other pathogens. Although established as a model for chemotaxis research, the majority of the 26 P. aeruginosa chemoreceptors remain functionally un-annotated. We report here the identification of PA5072 (named McpK) as chemoreceptor for α-ketoglutarate (αKG). High-throughput thermal shift assays and isothermal titration calorimetry studies (ITC) of the recombinant McpK ligand binding domain (LBD) showed that it recognizes exclusively α-ketoglutarate. The ITC analysis indicated that the ligand bound with positive cooperativity (Kd1 = 301 µM, Kd2 = 81 µM). McpK is predicted to possess a helical bimodular (HBM) type of LBD and this and other studies suggest that this domain type may be associated with the recognition of organic acids. Analytical ultracentrifugation (AUC) studies revealed that McpK-LBD is present in monomer-dimer equilibrium. Alpha-KG binding stabilized the dimer and dimer self-dissociation constants of 55 µM and 5.9 µM were derived for ligand-free and αKG-bound forms of McpK-LBD, respectively. Ligand-induced LBD dimer stabilization has been observed for other HBM domain containing receptors and may correspond to a general mechanism of this protein family. Quantitative capillary chemotaxis assays demonstrated that P. aeruginosa showed chemotaxis to a broad range of αKG concentrations with maximal responses at 500 µM. Deletion of the mcpK gene reduced chemotaxis over the entire concentration range to close to background levels and wild type like chemotaxis was recovered following complementation. Real-time PCR studies indicated that the presence of αKG does not modulate mcpK expression. Since αKG is present in plant root exudates it was investigated whether the deletion of mcpK altered maize root colonization. However, no significant changes with respect to the wild type strain were observed. The existence of a chemoreceptor specific for αKG may be due to its central metabolic role as well as to its function as signaling molecule. This work expands the range of known chemoreceptor types and underlines the important physiological role of chemotaxis toward tricarboxylic acid cycle intermediates.

Prevalence of musculoskeletal disorders and rheumatic diseases in the indigenous Qom population of Rosario, Argentina.

This study aimed to estimate the prevalence of musculoskeletal disorders and rheumatic diseases among the indigenous Qom (Toba) population in the city of Rosario, Santa Fe, Argentina. An analytical cross-sectional study using methodology of the Community Oriented Program for the Control of Rheumatic Diseases (COPCORD) was performed. Subjects ≥18 years of age were interviewed by advanced students of medicine and nursing, bilingual translator-facilitators, and coordinators. Individuals with musculoskeletal pain (positive cases) were evaluated sequentially for 7 days by internists and rheumatologists for diagnosis and treatment. The study included 1656 individuals (77 % of the census population). Of these, 1020 (61.5 %) were female, with mean age of 35.3 (SD 13.9) years, and 1028 (62.0 %) were bilingual. The public health care system covers 87.1 % of the population. Musculoskeletal pain in the previous 7 days and/or at some time during their life was present in 890 subjects (53.7 %). Of those with pain in the last 7 days, 302 (64.1 %) subjects had an Health Assessment Questionnaire Disability Index (HAQ-DI) score ≥0.8. The most frequent pain sites were lumbar spine (19.3 %), knees (13.0 %), and hands (12.0 %). The prevalence of rheumatic diseases was as follows: mechanical back pain (20.1 %), rheumatic regional pain syndrome (2.9 %), osteoarthritis (4.0 %) rheumatoid arthritis (2.4 %), inflammatory back pain (0.2 %), systemic sclerosis (0.1 %), Sjögren syndrome (0.1 %), fibromyalgia (0.1 %), mixed connective tissue disease (0.06 %), and systemic lupus erythematosus (0.06 %). The prevalence of musculoskeletal disorders was 53.7 % and rheumatic diseases 29.6 %. Rheumatoid arthritis prevalence was 2.4 % using COPCORD methodology, one of the highest reported at present.

Identification of a Chemoreceptor for C2 and C3 Carboxylic Acids.

Chemoreceptors are at the beginnings of chemosensory signaling cascades that mediate chemotaxis. Most bacterial chemoreceptors are functionally unannotated and are characterized by a diversity in the structure of their ligand binding domains (LBDs). The data available indicate that there are two major chemoreceptor families at the functional level, namely, those that respond to amino acids or to Krebs cycle intermediates. Since pseudomonads show chemotaxis to many different compounds and possess different types of chemoreceptors, they are model organisms to establish relationships between chemoreceptor structure and function. Here, we identify PP2861 (termed McpP) of Pseudomonas putida KT2440 as a chemoreceptor with a novel ligand profile. We show that the recombinant McpP LBD recognizes acetate, pyruvate, propionate, and l-lactate, with KD (equilibrium dissociation constant) values ranging from 34 to 107 µM. Deletion of the mcpP gene resulted in a dramatic reduction in chemotaxis toward these ligands, and complementation restored a native-like phenotype, indicating that McpP is the major chemoreceptor for these compounds. McpP has a CACHE-type LBD, and we present data indicating that CACHE-containing chemoreceptors of other species also mediate taxis to C2 and C3 carboxylic acids. In addition, the LBD of NbaY of Pseudomonas fluorescens, an McpP homologue mediating chemotaxis to 2-nitrobenzoate, bound neither nitrobenzoates nor the McpP ligands. This work provides further insight into receptor structure-function relationships and will be helpful to annotate chemoreceptors of other bacteria.

Specific gamma-aminobutyrate chemotaxis in pseudomonads with different lifestyle.

The PctC chemoreceptor of Pseudomonas aeruginosa mediates chemotaxis with high specificity to gamma-aminobutyric acid (GABA). This compound is present everywhere in nature and has multiple functions, including being a human neurotransmitter or plant signaling compound. Because P. aeruginosa is ubiquitously distributed in nature and able to infect and colonize different hosts, the physiological relevance of GABA taxis is unclear, but it has been suggested that bacterial attraction to neurotransmitters may enhance virulence. We report the identification of McpG as a specific GABA chemoreceptor in non-pathogenic Pseudomonas putida KT2440. As with PctC, GABA was found to bind McpG tightly. The analysis of chimeras comprising the PctC and McpG ligand-binding domains fused to the Tar signaling domain showed very high GABA sensitivities. We also show that PctC inactivation does not alter virulence in Caenorhabditis elegans. Significant amounts of GABA were detected in tomato root exudates, and deletion of mcpG reduced root colonization that requires chemotaxis through agar. The C. elegans data and the detection of a GABA receptor in non-pathogenic species indicate that GABA taxis may not be related to virulence in animal systems but may be of importance in the context of colonization and infection of plant roots by soil-dwelling pseudomonads.

The pGRT1 plasmid of Pseudomonas putida DOT-T1E encodes functions relevant for survival under harsh conditions in the environment.

Pseudomonas putida DOT-T1E has the capacity to grow in the presence of high concentrations of toluene. This ability is mainly conferred by an efflux pump encoded in a self-transmissible 133 kb plasmid named pGRT1. Sequence analysis of the pGRT1 plasmid revealed several key features. Most of the genes related to the plasmid maintenance functions show similarity with those encoded on pBVIE04 from Burkholderia vietnamensis G4, and knock-out mutants in several of these genes confirmed their roles. Two additional plasmid DNA fragments were incorporated into the plasmid backbone by recombination and/or transposition; in these DNA regions, apart from multiple recombinases and transposases, several stress-related and environmentally relevant functions are encoded. We report that plasmid pGRT1 not only confers the cells with tolerance to toluene but also resistance to ultraviolet light. We show here the implication of a new protein in solvent tolerance which controls the level of expression of the TtgGHI efflux pump, as well as the implication of a protein with homology to the universal stress protein in solvent tolerance and ultraviolet light resistance. Furthermore, this plasmid encodes functions that allow the cells to chemotactically respond to toluene and participate in iron scavenging.

Control of V(D)J Recombination through Transcriptional Elongation and Changes in Locus Chromatin Structure and Nuclear Organization.

V(D)J recombination is the assembly of gene segments at the antigen receptor loci to generate antigen receptor diversity in T and B lymphocytes. This process is regulated, according to defined developmental programs, by the action of a single specific recombinase complex formed by the recombination antigen gene (RAG-1/2) proteins that are expressed in immature lymphocytes. V(D)J recombination is strictly controlled by RAG-1/2 accessibility to specific recombination signal sequences in chromatin at several levels: cellular lineage, temporal regulation, gene segment order, and allelic exclusion. DNA cleavage by RAG-1/2 is regulated by the chromatin structure, transcriptional elongation, and three-dimensional architecture and position of the antigen receptor loci in the nucleus. Cis-elements specifically direct transcription and V(D)J recombination at these loci through interactions with transacting factors that form molecular machines that mediate a sequence of structural events. These events open chromatin to activate transcriptional elongation and to permit the access of RAG-1/2 to their recombination signal sequences to drive the juxtaposition of the V, D, and J segments and the recombination reaction itself. This chapter summarizes the advances in this area and the important role of the structure and position of antigen receptor loci within the nucleus to control this process.

Functional analysis of new transporters involved in stress tolerance in Pseudomonas putida DOT-T1E.

Pseudomonas putida DOT-T1E is a highly solvent-tolerant strain. Although the main mechanism that confers solvent tolerance to the strain is the TtgGHI efflux pump, a number of other proteins are also involved in the response to toluene. Previous proteomic and transcriptomic analysis carried out in our lab with P. putida DOT-T1E, and the solvent-sensitive strain, P. putida KT2440, revealed several transporters that were induced in the presence of toluene. We prepared five mutants of the corresponding genes in P. putida DOT-T1E and analysed their phenotypes with respect to solvent tolerance, stress endurance and growth with different carbon, nitrogen and sulfur sources. The data clearly demonstrated that two transporters (Ttg2ABC and TtgK) are involved in multidrug resistance and toluene tolerance, whereas another (homologous to PP0219 of P. putida KT2440) is a sulfate/sulfite transporter. No clear function could be assigned to the other two transporters. Of the transporters shown to be involved in toluene tolerance, one (ttg2ABC) belongs to the ATP-Binding Cassette (ABC) family, and is involved in multidrug resistance in P. putida DOT-T1E, while the other belongs to the Major Facilitator Superfamily and exhibits homology to a putative transporter of the Bcr/CflA family that has not previously been reported to be involved in toluene tolerance.

The ttgGHI solvent efflux pump operon of Pseudomonas putida DOT-T1E is located on a large self-transmissible plasmid.

Pseudomonas putida DOT-T1E is a solvent-tolerant strain able to grow in the presence of > 1% (v/v) toluene in the culture medium. A set of multidrug efflux pumps have been found to play a major role in the tolerance of this bacterium to organic solvents (Rojas et al., J Bacteriol 183: 3967-3973). In the course of studies of the mechanisms underlying solvent tolerance in DOT-T1E, we isolated a spontaneous solvent-sensitive mutant derivative which had lost the genes encoding the TtgGHI efflux pump, the most important extrusion element in quantitative terms. Genomic comparisons between the mutant and its parental strain by microarray analysis revealed that in addition to the ttgVW-ttgGHI gene cluster, another group of genes, highly similar to those found in the Tn4653A and ISPpu12 transposable elements of the TOL plasmid pWW0 from P. putida mt-2, were also absent from this strain. Further analysis demonstrated that strain DOT-T1E harboured a large plasmid (named pGRT1) that was lost from the solvent-sensitive mutant. Mapping analysis revealed that the ttgVW-ttgGHI genes and the Tn4653A-like transposon are borne by the pGRT1 plasmid. Plasmid pGRT1 is highly stable and its frequency of loss is below 10(-8) per cell per generation under a variety of growth conditions, including nutritional and physical stresses. The pGRT1 plasmid is self-transmissible, and its acquisition by the toluene-sensitive P. putida KT2440 and Pseudomonas aeruginosa PAO1 increased the recipient's tolerance to toluene up to levels similar to those exhibited by P. putida DOT-T1E. We discuss the importance and potential benefits of this plasmid for the development of bacteria with enhanced solvent tolerance, and its potential impact for bioremediation and whole-cell biotransformations.

Plasmolysis induced by toluene in a cyoB mutant of Pseudomonas putida.

The cyoABCDE gene cluster of Pseudomonas putida DOT-T1E encodes a terminal cytochrome oxidase. A 500-bp 'cyoB' DNA fragment was cloned in pCHESI Omega Km and used to generate a cyoB knock-out mutant in vivo. The mutant strain was not limited in the generation of proton-motif force, although when grown on minimal medium with glucose or citrate, the CyoB mutant exhibited a slight increase in duplication time with respect to the wild-type strain. This effect was even more pronounced when toluene was supplied in the gas phase. In consonance with the negative effect of toluene on the growth was the finding that the CyoB mutant was hypersensitive to sudden 0.3% (v/v) toluene shocks, in contrast with the wild-type strain. This effect was particularly exacerbated in cells that reached the stationary phase. The increased sensitivity to solvents of the CyoB mutant did not appear to be related to the inability of the cells to strengthen the membrane package or to induce the efflux pumps in response to the solvent, but rather to solvent-induced plasmolysis that may be triggered by wrinkles in the cytoplasmic membrane at the poles of the mutant cells, and invagination of the outer membranes, which eventually lead to cell death.