1,044 research outputs found

    Ultrasound Detects Subclinical Joint Inflammation in the Hands and Wrists of Patients With Systemic Lupus Erythematosus Without Musculoskeletal Symptoms

    Get PDF
    OBJECTIVES: To assess the prevalence and severity of ultrasonographic abnormalities of the hand and wrist of asymptomatic patients with systemic lupus erythematosus (SLE) and compare these findings with those from patients with SLE with musculoskeletal signs or symptoms and healthy controls. METHODS: We conducted a prospective cross-sectional study that evaluated bilaterally, with grey-scale and power Doppler (PD) ultrasound (US), the dorsal hand (2nd to 5th metacarpophalangeal and 2nd to 5th proximal interphalangeal joints) and wrist (radiocarpal, ulnocarpal and intercarpal joints) of 30 asymptomatic patients with SLE, 6 symptomatic patients with SLE and 10 controls. Synovial hypertrophy (SH) and intra-articular PD signal were scored using semiquantitative grading scales (0-3). Individual scores were graded as normal (SH≤1 and PD=0) or abnormal (SH≥2 or PD≥1). Global indexes for SH and PD were also calculated. US findings were correlated with clinical and laboratory data and disease activity indexes. RESULTS: US detected SH (score ≥1) in 77% asymptomatic patients with SLE, mostly graded as minimal (score 1: 63%). 23% of the asymptomatic patients with SLE showed abnormal US PD findings (SH≥2 or PD≥1). SH was present in all symptomatic patients with SLE, mostly graded as moderate (grade 2: 67%), and with associated PD signal (83%). SH (score 1) was identified in 50% of controls, however, none presented abnormal US PD findings. SH index in the asymptomatic SLE group was higher than in the control group (2.0 (0-5) vs 0.5 (0-2), median (range), p=0.01) and lower than in the symptomatic SLE group (7.0 (4-23), median (range), p<0.001). No significant correlation was demonstrated between US PD findings and clinical or laboratory variables and disease activity indexes. CONCLUSION: A small subgroup of asymptomatic patients with SLE may present subclinical joint inflammation. Global US scores and PD signal may be important in disease evaluation and therapeutic monitoring.info:eu-repo/semantics/publishedVersio

    Low frequency of CD4(+) CD25(+) Treg in SLE patients: a heritable trait associated with CTLA4 and TGF gene variants

    Get PDF
    Background: CD4(+)CD25(+) regulatory T cells play an essential role in maintaining immune homeostasis and preventing autoimmunity. Therefore, defects in Treg development, maintenance or function have been associated with several human autoimmune diseases including Systemic Lupus Erythematosus (SLE), a systemic autoimmune disease characterized by loss of tolerance to nuclear components and significantly more frequent in females

    Two Separate Effects Contribute to Regulatory T Cell Defect in Systemic Lupus Erythematosus Patients and Their Unaffected Relatives

    Get PDF
    Forkhead box P3 (FoxP3)+ regulatory T cells (Tregs ) are functionally deficient in systemic lupus erythematosus (SLE), characterized by reduced surface CD25 [the interleukin (IL)-2 receptor alpha chain]. Low-dose IL-2 therapy is a promising current approach to correct this defect. To elucidate the origins of the SLE Treg phenotype, we studied its role through developmentally defined regulatory T cell (Treg ) subsets in 45 SLE patients, 103 SLE-unaffected first-degree relatives and 61 unrelated healthy control subjects, and genetic association with the CD25-encoding IL2RA locus. We identified two separate, uncorrelated effects contributing to Treg CD25. (1) SLE patients and unaffected relatives remarkably shared CD25 reduction versus controls, particularly in the developmentally earliest CD4+ FoxP3+ CD45RO- CD31+ recent thymic emigrant Tregs . This first component effect influenced the proportions of circulating CD4+ FoxP3high CD45RO+ activated Tregs . (2) In contrast, patients and unaffected relatives differed sharply in their activated Treg CD25 state: while relatives as control subjects up-regulated CD25 strongly in these cells during differentiation from naive Tregs , SLE patients specifically failed to do so. This CD25 up-regulation depended upon IL2RA genetic variation and was related functionally to the proliferation of activated Tregs , but not to their circulating numbers. Both effects were found related to T cell IL-2 production. Our results point to (1) a heritable, intrathymic mechanism responsible for reduced CD25 on early Tregs and decreased activation capacity in an extended risk population, which can be compensated by (2) functionally independent CD25 up-regulation upon peripheral Treg activation that is selectively deficient in patients. We expect that Treg -directed therapies can be monitored more effectively when taking this distinction into account.info:eu-repo/semantics/publishedVersio

    Genome of the Avirulent Human-Infective Trypanosome—Trypanosoma rangeli

    Get PDF
    Background: Trypanosoma rangeli is a hemoflagellate protozoan parasite infecting humans and other wild and domestic mammals across Central and South America. It does not cause human disease, but it can be mistaken for the etiologic agent of Chagas disease, Trypanosoma cruzi. We have sequenced the T. rangeli genome to provide new tools for elucidating the distinct and intriguing biology of this species and the key pathways related to interaction with its arthropod and mammalian hosts.  Methodology/Principal Findings: The T. rangeli haploid genome is ,24 Mb in length, and is the smallest and least repetitive trypanosomatid genome sequenced thus far. This parasite genome has shorter subtelomeric sequences compared to those of T. cruzi and T. brucei; displays intraspecific karyotype variability and lacks minichromosomes. Of the predicted 7,613 protein coding sequences, functional annotations could be determined for 2,415, while 5,043 are hypothetical proteins, some with evidence of protein expression. 7,101 genes (93%) are shared with other trypanosomatids that infect humans. An ortholog of the dcl2 gene involved in the T. brucei RNAi pathway was found in T. rangeli, but the RNAi machinery is non-functional since the other genes in this pathway are pseudogenized. T. rangeli is highly susceptible to oxidative stress, a phenotype that may be explained by a smaller number of anti-oxidant defense enzymes and heatshock proteins.  Conclusions/Significance: Phylogenetic comparison of nuclear and mitochondrial genes indicates that T. rangeli and T. cruzi are equidistant from T. brucei. In addition to revealing new aspects of trypanosome co-evolution within the vertebrate and invertebrate hosts, comparative genomic analysis with pathogenic trypanosomatids provides valuable new information that can be further explored with the aim of developing better diagnostic tools and/or therapeutic targets

    High levels of genetic differentiation and selfing in the Brazilian cerrado fruit tree Dipteryx alata Vog. (Fabaceae)

    Get PDF
    Dipteryx alata is a native fruit tree species of the cerrado (Brazilian savanna) that has great economic potential because of its multiple uses. Knowledge of how the genetic variability of this species is organized within and among populations would be useful for genetic conservation and breeding programs. We used nine simple sequence repeat (SSR) primers developed for Dipteryx odorata to evaluate the genetic structure of three populations of D. alata located in central Brazil based on a leaf sample analysis from 101 adults. The outcrossing rate was evaluated using 300 open-pollinated offspring from 25 seed-trees. Pollen dispersal was measured by parentage analysis. We used spatial genetic structure (SGS) to test the minimal distance for harvesting seeds in conservation and breeding programs. Our data indicate that the populations studied had a high degree of genetic diversity and population structure, as suggested by the high level of divergence among populations . The estimated outcrossing rate suggested a mixed mating system, and the intrapopulation fixation index was influenced by SGS. We conclude that seed harvesting for genetic conservation and breeding programs requires a minimum distance between trees of 196 m to avoid collecting seeds from related seed-trees
    corecore