89 research outputs found
Heparin Increases HLA-G Levels in Primary Antiphospholipid Syndrome
Objectives. The aim of this study was to investigate the HLA-G serum levels in Primary Antiphospholipid Syndrome (PAPS) patients, its impact on clinical and laboratory findings, and heparin treatment. Methods. Forty-four PAPS patients were age and gender matched with 43 controls. HLA-G serum levels were measured using an enzyme-linked immunosorbent assay (ELISA). Results. An increase in soluble HLA-G levels was found in patients compared to controls (3.35 (0â22.9) versus 1.1 (0â14), P = 0.017). There were no significant differences in HLA-G levels between patients with and without obstetric events, arterial thrombosis, venous thrombosis, or stroke. Sixty-six percent of patients were being treated with heparin. Interestingly, patients treated with heparin had higher HLA-G levels than ones who were not treated with this medication (5 (0â22.9) versus 1.8 (0â16)âng/mL, P = 0.038). Furthermore, patients on heparin who experienced obstetric events had a trend to increased HLA-G levels compared to patients who were not on heparin and did not have obstetric events (5.8 (0â22.9) versus 2 (0â15.2)âng/mL, P = 0.05). Conclusion. This is the first study to demonstrate that serum HLA-G levels are increased in APS patients. We also demonstrated that heparin increases HLA-G levels and may increase tolerance towards autoantigens
Heparin Increases HLA-G Levels in Primary Antiphospholipid Syndrome
Objectives. The aim of this study was to investigate the HLA-G serum levels in Primary Antiphospholipid Syndrome (PAPS) patients, its impact on clinical and laboratory findings, and heparin treatment. Methods. Forty-four PAPS patients were age and gender matched with 43 controls. HLA-G serum levels were measured using an enzyme-linked immunosorbent assay (ELISA). Results. An increase in soluble HLA-G levels was found in patients compared to controls (3.35 (0â22.9) versus 1.1 (0â14), P = 0.017). There were no significant differences in HLA-G levels between patients with and without obstetric events, arterial thrombosis, venous thrombosis, or stroke. Sixty-six percent of patients were being treated with heparin. Interestingly, patients treated with heparin had higher HLA-G levels than ones who were not treated with this medication (5 (0â22.9) versus 1.8 (0â16)âng/mL, P = 0.038). Furthermore, patients on heparin who experienced obstetric events had a trend to increased HLA-G levels compared to patients who were not on heparin and did not have obstetric events (5.8 (0â22.9) versus 2 (0â15.2)âng/mL, P = 0.05). Conclusion. This is the first study to demonstrate that serum HLA-G levels are increased in APS patients. We also demonstrated that heparin increases HLA-G levels and may increase tolerance towards autoantigens
Personalized whole-brain neural mass models reveal combined AÎČ and tau hyperexcitable influences in Alzheimerâs disease
Neuronal dysfunction and cognitive deterioration in Alzheimerâs disease (AD) are likely caused by multiple pathophysiological factors. However, mechanistic evidence in humans remains scarce, requiring improved non-invasive techniques and integrative models. We introduce personalized AD computational models built on whole-brain Wilson-Cowan oscillators and incorporating resting-state functional MRI, amyloid-ÎČ (AÎČ) and tau-PET from 132 individuals in the AD spectrum to evaluate the direct impact of toxic protein deposition on neuronal activity. This subject-specific approach uncovers key patho-mechanistic interactions, including synergistic AÎČ and tau effects on cognitive impairment and neuronal excitability increases with disease progression. The data-derived neuronal excitability values strongly predict clinically relevant AD plasma biomarker concentrations (p-tau217, p-tau231, p-tau181, GFAP) and grey matter atrophy obtained through voxel-based morphometry. Furthermore, reconstructed EEG proxy quantities show the hallmark AD electrophysiological alterations (theta band activity enhancement and alpha reductions) which occur with AÎČ-positivity and after limbic tau involvement. Microglial activation influences on neuronal activity are less definitive, potentially due to neuroimaging limitations in mapping neuroprotective vs detrimental activation phenotypes. Mechanistic brain activity models can further clarify intricate neurodegenerative processes and accelerate preventive/treatment interventions
Coinfection with Different Trypanosoma cruzi Strains Interferes with the Host Immune Response to Infection
A century after the discovery of Trypanosoma cruzi in a child living in Lassance, Minas Gerais, Brazil in 1909, many uncertainties remain with respect to factors determining the pathogenesis of Chagas disease (CD). Herein, we simultaneously investigate the contribution of both host and parasite factors during acute phase of infection in BALB/c mice infected with the JG and/or CL Brener T. cruzi strains. JG single infected mice presented reduced parasitemia and heart parasitism, no mortality, levels of pro-inflammatory mediators (TNF-α, CCL2, IL-6 and IFN-γ) similar to those found among naïve animals and no clinical manifestations of disease. On the other hand, CL Brener single infected mice presented higher parasitemia and heart parasitism, as well as an increased systemic release of pro-inflammatory mediators and higher mortality probably due to a toxic shock-like systemic inflammatory response. Interestingly, coinfection with JG and CL Brener strains resulted in intermediate parasitemia, heart parasitism and mortality. This was accompanied by an increase in the systemic release of IL-10 with a parallel increase in the number of MAC-3+ and CD4+ T spleen cells expressing IL-10. Therefore, the endogenous production of IL-10 elicited by coinfection seems to be crucial to counterregulate the potentially lethal effects triggered by systemic release of pro-inflammatory mediators induced by CL Brener single infection. In conclusion, our results suggest that the composition of the infecting parasite population plays a role in the host response to T. cruzi in determining the severity of the disease in experimentally infected BALB/c mice. The combination of JG and CL Brener was able to trigger both protective inflammatory immunity and regulatory immune mechanisms that attenuate damage caused by inflammation and disease severity in BALB/c mice
Comparative genomics of proteins involved in RNA nucleocytoplasmic export
Background: The establishment of the nuclear membrane resulted in the physical separation of transcription and translation, and presented early eukaryotes with a formidable challenge: how to shuttle RNA from the nucleus to the locus of protein synthesis. In prokaryotes, mRNA is translated as it is being synthesized, whereas in eukaryotes mRNA is synthesized and processed in the nucleus, and it is then exported to the cytoplasm. In metazoa and fungi, the different RNA species are exported from the nucleus by specialized pathways. For example, tRNA is exported by exportin-t in a RanGTP-dependent fashion. By contrast, mRNAs are associated to ribonucleoproteins (RNPs) and exported by an essential shuttling complex (TAP-p15 in human, Mex67-mtr2 in yeast) that transports them through the nuclear pore. The different RNA export pathways appear to be well conserved among members of Opisthokonta, the eukaryotic supergroup that includes Fungi and Metazoa. However, it is not known whether RNA export in the other eukaryotic supergroups follows the same export routes as in opisthokonts.
Methods: Our objective was to reconstruct the evolutionary history of the different RNA export pathways across eukaryotes. To do so, we screened an array of eukaryotic genomes for the presence of homologs of the proteins involved in RNA export in Metazoa and Fungi, using human and yeast proteins as queries.
Results: Our genomic comparisons indicate that the basic components of the RanGTP-dependent RNA pathways are conserved across eukaryotes, and thus we infer that these are traceable to the last eukaryotic common ancestor (LECA). On the other hand, several of the proteins involved in RanGTP-independent mRNA export pathways are less conserved, which would suggest that they represent innovations that appeared later in the evolution of eukaryotes.
Conclusions: Our analyses suggest that the LECA possessed the basic components of the different RNA export mechanisms found today in opisthokonts, and that these mechanisms became more specialized throughout eukaryotic evolution
Edentulism and shortened dental arch in Brazilian elderly from the National Survey of Oral Health 2003
OBJECTIVE: To describe the distribution of edentulism and estimate the prevalence of functional dentition and shortened dental arch among elderly population. METHODS: A population-based epidemiological study was carried out with a sample of 5,349 respondents aged 65 to 74 years obtained from the 2002 and 2003 Brazilian Ministry of Health/Division of Oral Health survey database. The following variables were studied: gender; macroregion of residence; missing teeth; percentage that met the World Health Organization goal for oral health in the age group 65 to 74 years (50% having at least 20 natural teeth); presence of shortened dental arch; number of posterior occluding pairs of teeth. The Chi-square test assessed the association between categorical variables. The Kruskal-Wallis and Mann-Whitney tests were used to assess differences of mean between number of posterior occluding pairs teeth, macro-region and gender. RESULTS: The elderly population had an average of 5.49 teeth (SD: 7.93) with a median of 0. The proportion of completely edentulous respondents was 54.7%. Complete edentulism was 18.2% in the upper arch and 1.9% in the lower arch. The World Health Organization goal was achieved in 10% of all respondents studied. However, only 2.7% had acceptable masticatory function and aesthetics (having at least shortened dental arch) and a mean number of posterior occluding pairs of 6.94 (SD=2.97). There were significant differences of the percentage of respondents that met the World Health Organization goal and presence of shortened dental arch between men and women. There were differences in shortened dental arch between macroregions. CONCLUSIONS: The Brazilian epidemiological oral health survey showed high rate of edentulism and low rate of shortened dental arch in the elderly population studied, thus suggesting significant functional and aesthetic impairment in all Brazilian macroregions especially among women
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