IL-17 and related cytokines involved in systemic sclerosis: Perspectives

Systemic sclerosis (SSc) is a multisystemic, complex, and rare disease of connective tissue, with high morbidity and mortality, and without specific treatment. The disease is characterized by three main principles: vascular disease, autoantibody production and inflammation, and fibrosis. Since it is well defined that SSc is characterized by elevated production of TGF-β, IL-6, and IL-1, all of them cytokines related to Th17 differentiation, the hypothesis is that this disease may be strongly related to a polarization of the immune response towards the Th17 pathway. Considering the importance of a better understanding of the pathophysiology of Th17 pathway in SSc, this article aims to propose an update for a better understanding of current knowledge on main cytokines secreted by the Th17 cells (IL-17?A, IL-21, and IL-22) and the future prospects in the current disease.     

Visual and visuomotor processing of hands and tools as a case study of cross talk between the dorsal and ventral streams

A major principle of organization of the visual system is between a dorsal stream that processes visuomotor information and a ventral stream that supports object recognition. Most research has focused on dissociating processing across these two streams. Here we focus on how the two streams interact. We tested neurologically-intact and impaired participants in an object categorization task over two classes of objects that depend on processing within both streams—hands and tools. We measured how unconscious processing of images from one of these categories (e.g., tools) affects the recognition of images from the other category (i.e., hands). Our findings with neurologically-intact participants demonstrated that processing an image of a hand hampers the subsequent processing of an image of a tool, and vice versa. These results were not present in apraxic patients (N?=?3). These findings suggest local and global inhibitory processes working in tandem to co-register information across the two streams.     

Chagas' disease diagnosis: evaluation of several tests in blood bank screening

Blood transfusion is one of the principal routes of transmission of Chagas' disease, a major endemic disease in Latin America. Methods for blood screening are not accurate and may yield false results that lead to high social and economic costs. This study compares two methods of diagnosing Chagas' disease (indirect immunofluorescence and hemagglutination) and several enzyme-linked immunosorbent assays (ELISAs) with regard to specificity and sensitivity, by using human sera with known serologic and parasitologic characteristics, as well as samples with discrepant results on conventional serologic tests. An ELISA using recombinant antigens showed no cross-reactivity with sera that were positive for other diseases. All evaluated ELISAs performed well, and their use may lead to a reduction of more than 50 percent in the number of discordant sera. Further improvements are needed in view of the complexity of the serologic diagnosis of Chagas' disease.     

Quantitative real-time PCR for differential diagnostics of parvovirus B19 infection in acute liver failure patients

Background: Human Parvovirus B19 (B19V) is a common pathogen worldwide. After primary infection, B19V-DNA may permanently persist in non-erythroid tissues, including the liver of patients with acute liver failure (ALF).

Objective: To validate a real-time PCR (qPCR) for the quantification of B19V-DNA, in order to establish a differential diagnosis for B19V infection in ALF patients.

Methods: The qPCR techniques were based on Sybr Green® and TaqMan® methodologies. To evaluate the quality parameters of both methods, samples from patients with or without B19V infection were tested. The diagnostic utility of qPCR in the detection B19V-DNA in patients with ALF was evaluated by testing archived serum and hepatic tissue explants from 10 patients.

Results: The Sybr Green® methodology showed 97% efficiency, the limits of detection and quantification were 62.6 and 53,200 copies/mL, respectively. The TaqMan® methodology showed 95% efficiency, the limits of detection and quantification were 4.48 and 310 copies/mL, respectively. A false positive result was found only with the Sybr Green® methodology. Among ALF patients without defined etiology, three (30%) were positive for B19V DNA in serum and liver.

Conclusion: The qPCR methods validated here were effective in clarifying uncommon cases of B19V-related ALF and are fit for differential diagnosis of ALF causes.     

Origins of the Xylella fastidiosa Prophage-Like Regions and Their Impact in Genome Differentiation

Xylella fastidiosa is a Gram negative plant pathogen causing many economically important diseases, and analyses of completely sequenced X. fastidiosa genome strains allowed the identification of many prophage-like elements and possibly phage remnants, accounting for up to 15% of the genome composition. To better evaluate the recent evolution of the X. fastidiosa chromosome backbone among distinct pathovars, the number and location of prophage-like regions on two finished genomes (9a5c and Temecula1), and in two candidate molecules (Ann1 and Dixon) were assessed. Based on comparative best bidirectional hit analyses, the majority (51%) of the predicted genes in the X. fastidiosa prophage-like regions are related to structural phage genes belonging to the Siphoviridae family. Electron micrograph reveals the existence of putative viral particles with similar morphology to lambda phages in the bacterial cell in planta. Moreover, analysis of microarray data indicates that 9a5c strain cultivated under stress conditions presents enhanced expression of phage anti-repressor genes, suggesting switches from lysogenic to lytic cycle of phages under stress-induced situations. Furthermore, virulence-associated proteins and toxins are found within these prophage-like elements, thus suggesting an important role in host adaptation. Finally, clustering analyses of phage integrase genes based on multiple alignment patterns reveal they group in five lineages, all possessing a tyrosine recombinase catalytic domain, and phylogenetically close to other integrases found in phages that are genetic mosaics and able to perform generalized and specialized transduction. Integration sites and tRNA association is also evidenced. In summary, we present comparative and experimental evidence supporting the association and contribution of phage activity on the differentiation of Xylella genomes.     

Diagnostic Accuracy of Coronary CT Angiography for the Evaluation of Bioresorbable Vascular Scaffolds

Objectives

The purpose of this study was to assess the diagnostic accuracy of coronary computed tomography angiography (CTA) for bioresorbable vascular scaffold (BVS) evaluation.

Oral refeeding in patients with mild acute pancreatitis: prevalence and risk factors of relapsing abdominal pain

BACKGROUND AND AIM: In acute pancreatitis (AP), oral refeeding may stimulate pancreatic secretion, increasing the inflammation of the glandular tissue causing relapse of abdominal pain or even exacerbation of the disease. This study aimed to assess the prevalence and risk factors of abdominal pain relapse over oral refeeding in patients convalescing with AP as well as the impact of pain recurrence on the hospital stay. METHODS: Inclusion criteria were AP confirmed by biochemical and/or radiological data in the absence of severe disease or extensive necrosis. The same diet was offered to all patients during oral refeeding. Demographic, clinical, biochemical and radiological data were prospectively recorded and analyzed. RESULTS: A total of 130 patients were included. During the oral refeeding period, 32 (24.6%) patients had pain relapse, which was more common on days 1 (68.8%) and 2 (28.1%). Pain relapse was related to higher serum levels of lipase on the day before refeeding, higher serum levels of C-reactive protein on the fourth day, and presence of peripancreatic fluid collections (P < 0.01). Pain relapse significantly increased total hospital stay (P < 0.01). CONCLUSIONS: In patients with mild AP, pain relapse during oral refeeding was relatively high (24.6%), particularly on the first or second day. Their risk appeared be associated with more intense or persistent pancreatic inflammation on the day before refeeding, and presence of peripancreatic fluid collections. Pain relapse increased hospital stay, and likely overall costs on disease treatment.     

Clinical and immunologic evaluation of 31 patients with acute schistosomiasis mansoni.

Thirty-one patients with acute schistosomiasis were evaluated clinically and immunologically. Cytokine levels were determined in peripheral blood mononuclear cell (PBMC) supernatants. Levels of total and antigen-specific IgE, tumor necrosis factor (TNF)-alpha, and immune complexes were measured in serum samples. Clinical findings included general symptoms, liver damage, pulmonary involvement, and pericarditis. All patients had eosinophilia. Immune complexes were detected in 55% of the patients (mean+/-SD, 7.8+/-7.6 microg Eq/mL) and were associated with cough, dyspnea, and abnormal chest radiographic findings. Levels (mean +/- SD) of TNF-alpha (1349.3+/-767.6 pg/mL), interleukin (IL)-1 (2683+/-1270 pg/mL), and IL-6 (382 +/- 52.3 pg/mL) were elevated in PBMC. Serum TNF-alpha levels were elevated in 87% of the patients and were associated with abdominal pain. Higher interferon-gamma levels were detected in PBMC of patients with acute disease than in those of patients with chronic schistosomiasis; IL-5 levels were higher in those with chronic disease. Low IL-5 levels were associated with weight loss. Proinflammatory cytokines and immune complexes with low Th2 responses might explain the immunopathogenesis of acute schistosomiasis.