Is the IL-10 −819 Polymorphism Associated with Visceral Leishmaniasis?

Previous investigations demonstrated that immune responses play critical roles in the defense against visceral leishmaniasis (VL). A key regulator of immune responses is the cytokine, IL-10 and polymorphisms within its promoter which could alter its expression. Thus, the aim of this study was to examine the correlation between polymorphism at the ?819 position of the IL-10 gene and VL in a selected Iranian population. This cross-sectional study was performed on 100 patients with clinical presentation of VL and seropositive for the leishmania (group 1), 62 patients without clinical presentation but seropositive (group 2), and 128 healthy controls (group 3). The IL-10 ?819 polymorphism was evaluated using the PCR-RFLP technique. The anti-leishmania antibody titration was assessed using an immunofluorescence assay. Our results showed that the polymorphism at IL-10 ?819 (C/T) position was significantly associated with VL, and C/T genotype was significantly higher in VL patients when compared to groups 2 and 3 (p?<?0.001). However, the results demonstrated that the C and T alleles were not associated with VL (p?=?0.855). The data presented here confirm the results of previous reports that polymorphisms at the ?819 position of the IL-10 gene can influence susceptibility to VL suggesting that the C/T genotype may be considered as a risk factor for the disease.     

An exciplex-based, target-assembled fluorescence system with inherently low background to probe for specific nucleic acid sequences

A novel detection technique, called ExciProbes, has been developed to proof-of-principle level for DNA oligonucleotides. The new approach is based on the use of two short oligonucleotides complementary to a target nucleic acid sequence. Each short-probe oligonucleotide bears the separated parts of a new class of fluorescence detector, an exciplex. These isolated parts of the detector have no inherent signal at the detection wavelength. They are designed to detect biotarget by being assembled by the target itself to give a new molecular entity (the exciplex), with a characteristic fluorescence and very large Stokes shift (typically >150 nm). The technique is not related to fluorescence resonance energy transfer, and can potentially resolve to 1 base pair. ExciProbes can detect single or double mutations in a short sequence of DNA, and can be combined with temperature-filtering to provide allelic discrimination of single nucleotide polymorphism analysis. Compared to other fluorophore systems that have large backgrounds (typically >60%), ExciProbes show backgrounds of <1% under comparable conditions, and can be used with DNA, RNA, or synthetic nucleic acids such as locked nucleic acid.     

In Vitro Analysis of CsA-Induced Hepatotoxicity in HepG2 Cell Line: Oxidative Stress and α2 and β1 Integrin Subunits Expression

Background

Cyclosporine A (CsA)-induced hepatotoxicity could be due to a reduction in α2β1 integrin expression that may either be from the direct effect of CsA itself or from reactive oxygen species (ROS) overproduction.

Objectives

In this study we aimed to identify the cellular mechanisms underlying CsA-induced hepatic injury by investigating the activation patterns of the antioxidant enzymes, using HepG2 as an in vitro model.

Materials and Methods

HepG2 cells were cultured with different concentrations of CsA (0, 0.1, 1, 10 μg/ml) for 72 h. Effect of CsA on, 1) cellular integrity, 2) glutathione reductase (GR) and glutathione peroxidase (GPx) activity, 3) cellular levels of glutathione (GSH), 4) intracellular ROS, 5) ALT and AST activities, 6) urea production and 7) α2β1 integrin expression were assayed.

Results

CsA treatment demonstrated a dose dependent increase in intracellular levels of ROS, GPx activity and decrease in GSH levels (P<0.05). GR activity was mildly attenuated in 1 and 10 µg/ml concentrations of CsA. Alanine aminotranferase (ALT) and aspartate aminotransferase (AST) levels increased in CsA treated cells, while urea synthesis was significantly decreased following treatment with higher concentrations of CsA (P<0.05). Significant down-regulation of β1integrin expression was observed in 1 and 10 µg/ml CsA treated cells while α2 integrin mRNA was significantly down-regulated in all CsA treated cells.

Conclusions

The observed reduction of α2β1 integrin expression following CsA treatment could be proposed as a possible pathway of CsA-induced hepatotoxicity. Further studies are required to elucidate whether this attenuated expression is due to the direct effect of CsA or caused by overproduction of ROS.     

Interictal levels of calcitonin gene related peptide in gingival crevicular fluid of chronic migraine patients

Calcitonin gene related peptide (CGRP) is a mediator of neurogenic inflammation playing a major role in the pathogenesis of migraine. Increases in serum CGRP have been detected previously in migraineurs and a return to baseline values regarded as successful treatment. As gingival crevicular fluid is known to originate from the serum, the aim of this study is to measure the CGRP content of gingival crevicular fluid (GCF) in chronic migraine patients and to determine whether there is a correlation between serum and GCF values of CGRP. For this study, 24 female individuals suffering from chronic migraine with aura were age-matched with 15 healthy individuals. Serum and GCF samples were obtained from both groups and enzyme linked immunosorbent assay performed to measure CGRP concentration. The level of CGRP in the serum and GCF of chronic migraine patients was 41?±?16 pg/mL and 0.25?±?0.09 pg/μg respectively while in healthy individuals CGRP levels were 29?±?8 pg/mL and 0.19?±?0.07 pg/μg. The correlation between CGRP levels of the GCF and serum was 0.88 for migraineurs and 0.81 in the controls. Only a weak positive relationship was observed between age and CGRP levels in both groups. CGRP levels were higher in migraineurs compared with controls both in serum and GCF. Furthermore there is a strong correlation between CGRP levels of the serum and GCF. The results of this study suggest that CGRP levels of GCF have potential diagnostic purposes in patients with chronic migraine.     

The effect of vertical bracket positioning on torque and the resultant stress in the periodontal ligament—a finite element study

Background

The ideal built-in tip and torque values of the straight wire appliance reduce the need for wire bending and hence reduce chair time. The vertical position of the bracket on the tooth surface can alter the torque exerted on the tooth. This is a result of the altered surface curvature observed at each vertical position. To further clarify the role of vertical bracket positioning on the applied torque and the resultant stresses in the periodontal ligament (PDL), we designed a mandibular first premolar using finite element modeling.

Methods

Cone beam computed tomography of 52 patients (83 lower first premolars) was selected to be included in the study. Curvature was measured for points along the labial surface with increasing distances (0.5 mm increments) from the cusp tip by calculating the angle between tangents drawn from these points and the axis joining the cusp tip and the root apex. The mean values for each distance were calculated, and a finite element model was designed incorporating these mean values. The resultant stress and hydrostatic pressure in the PDL were calculated using finite element analysis.

Results

The labial surface of the mandibular first premolar demonstrated a 26.39° change from 2.5 to 6 mm from the cusp tip. The maximum Von-Mises stress and hydrostatic pressure in the PDL were observed at the root apex for all of the bracket positions, and these values demonstrated, respectively, a change of up to 0.059 and 0.186 MPa between two successive points.

Conclusions

It can be concluded that the variation in the vertical position of the bracket can have an important effect on the torque and subsequently on the stresses and pressures in the PDL.