Can Toll-Like Receptor (TLR) 2 be considered as a new target for immunotherapy against hepatitis B infection?

The current literature describes pivotal mechanisms in which hepatitis B virus (HBV) induces liver diseases including inflammation, cirrhosis and hepatocellular carcinoma (HCC). It appears that differences in genetic and immunological parameters between patients and controls may be responsible for inducing the prolonged forms of the infection. Previous studies demonstrated that Toll-Like Receptors (TLRs) play key roles in viral recognition and inducing appropriate immune responses. Therefore, TLRs can be considered as key sensors for HBV recognition and subsequent induction of immune responses against this virus. It has also been shown that the TLR2 detects several microbial PAMPs either in its homodimer form or in a heterodimer with TLR1 or TLR6 and subsequently activates NF-κB in a MYD88 dependent manner. Therefore, defective TLR2 expression may result in impaired immune responses against HBV which is reported in long-term forms of hepatitis B. This review presents the recent data regarding the status and important roles played by TLR2 in HBV recognition and induction or suppression of immune responses against HBV as well as its roles in the pathogenesis of cirrhosis and HCC in prolonged hepatitis B forms.     

FOXP3 expression and frequency of regulatory T cells in healed individuals from Leishmania major infection and the asymptomatic cases

Two groups of residents in an endemic area of Leishmania major infection in Iran with positive leishmanin skin tests who were either asymptomatic or had healed cutaneous leishmaniasis lesions were compared with respect to their T helper responses. The percentages of regulatory T cells (T_reg; CD4⁺CD25^high FoxP3⁺) from the peripheral blood and CD4⁺ T cells producing intracellular cytokines (IL-4, IL-10, IL-17 and IFN-γ) from the stimulated PBMCs were evaluated by flow cytometry and the expressions of RORC and FOXP3 genes were quantified by real-time RT-PCR. T responder (CD4⁺CD25⁻) and T_reg-enriched (CD4⁺CD25⁺) cells were isolated magnetically and the suppressive capacity of the latter and the cytokines (IFN-γ, TGF-β and IL-10) secreted from them were evaluated by in vitro assays. The results showed that the frequency of T_reg in the studied groups were similar and T_reg from both groups exhibited high yet similar suppressive capacities while significantly higher levels of FOXP3 expression was observed in the asymptomatic group. Taken together, similar frequency and suppressiveness of T_reg combined with high ratios of IFN-γ/IL-10 producing CD4⁺ T cells were common in both groups; however the members of the asymptomatic group appeared to require higher expression of FOXP3 to maintain their immunity to re-infection.     

Serum copper,zinc, and iron concentrations of Holstein dairy cows in different seasonal and physiological states

The aim of the present study was to determine the serum copper (Cu), zinc (Zn), and iron (Fe) concentrations of Holstein dairy cows in different seasonal and physiological states. A total of 250 blood samples were collected from healthy Holstein dairy cows. Blood samples were divided according to season, pregnancy, gestation period, calving number, and milk yield. The Cu, Fe, and Zn contents were assessed in samples using atomic absorption spectrophotometer. Neither the seasonal nor the physiological changes affect mean serum Cu and Fe concentrations of Holstein dairy cattle. Mean Zn concentrations in serum vary only with physiological changes, including gestation period and milk yield. In cattle groups divided based on gestation period, the mean serum Zn concentrations were significantly higher for under 3 months than for 6–9 months (P?<?0.05). In cattle groups divided based on daily milk yield, the highest serum Zn concentrations were related to the group under 10 kg/day (P?<?0.05). In present study, although slight differences were observed in serum Cu, Zn, and Fe concentration in different seasonal and physiological states, especial care must be taken when concentrates are supplemented in different physiological states of Holstein dairy cows by trace elements.     

Utility of P16 expression and Ki‐67 proliferation index in ASCUS and ASC‐H pap tests

Current cervical screening uses a combination of cytology and high‐risk human papillomavirus (HR‐HPV) analysis in cases of atypical squamous cells of undetermined significance (ASCUS) and atypical squamous cells cannot exclude high‐grade intraepithelial lesion (ASC‐H). These diagnoses are subject to interobserver variability and HR‐HPV analysis can be limited by sampling inadequacy. This study correlates immunoexpression of P16 and Ki‐67 in residual cervicovaginal material against cytology category and HR‐HPV status. Eighteen pap tests were selected: 8 ASCUS, 4 ASC‐H, and 6 controls (2 LSIL and 4 HSIL). Digene Hybrid Capture II test was used to detect HR‐HPV. The cytospins were stained for P16/Ki‐67. Pap tests, P16, Ki‐67, HR‐HPV result and available biopsies were correlated. P16 expression correlated with HR‐HPV status in 15/17 cases. Discordant cases (1 ASCUS and 1 ASC‐H) were +P16/–HR‐HPV. Ki‐67 correlated with HR‐HPV in 8/15 cases. Discordant cases were +HR‐HPV/– Ki‐67 (HSIL, LSIL, and ASC‐H one each), and –HR‐HPV/+Ki‐67 (3 ASCUS, 1 LSIL, 1 ASC‐H). Two cases were + P16/+ Ki‐67/– HR‐HPV. None were ‐ P16/– Ki‐67/+ HR‐HPV. Histologic follow‐up in 13 cases varied from benign to CIN III. Two cases of +P16/ – Ki‐67/– HR‐HPV had benign cervical biopcies. Although a small sample size, our findings show a utility for adjunct P16/ Ki‐67 in addition to HR‐HPV testing in cases of squamous atypia when HR‐HPVs are non‐detected due to low DNA copies, or missed lesions in cervical biopsies. Diagn. Cytopathol. 2014;42:576–581. © 2013 Wiley Periodicals, Inc.     

Fine‐needle aspiration of squamous‐lined cysts of the pancreas

Squamous‐lined cysts (SLC) in the pancreas are rare and include lymphoepithelial cysts (LEC), dermoid cysts (DC), and epidermoid cysts in heterotopic spleen (EC). Previously only rare case reports and small case series have been published describing the FNA findings in these entities. The departmental archives were searched for surgically excised SLC from the pancreas. Twenty‐five specimens were identified: 20 LEC, four EC, and one DC. Eight corresponding FNA specimens taken prior to resection were identified and available for review: seven LEC and one EC. A junior and senior pathologist reviewed the cases individually and then together for consensus. On morphological review, all lesions contained single nucleated and anucleated mature squamous cells, macrophages, and varying amounts of lymphocytes. Benign squamous fragments were found in half of all specimens. Amorphous debris was found in all cases. Keratin was found in all but two cases and its appearance varied among cases. Half of all cases contained cholesterol crystals. No nuclear atypia or necrosis was noted. Inspissated mucin, a potentially misleading finding, was seen in three cases. The most important goal in evaluating pancreatic cystic lesions is to exclude a mucin‐producing neoplasm. If features of a SLC are present, the differential diagnosis should include LEC, DC, and EC. Only 38% (3/8) cases had the most specific features of an SLC present (squamous fragments, cholesterol crystals, keratin, and squamous cells), which suggests that most cases will not be specifically identified on FNA even by experienced cytopathologists. Diagn. Cytopathol. 2014;42:592–599. © 2013 Wiley Periodicals, Inc.     

Investigation of the biological activity,mechanical properties and wound healing application of a novel scaffold based on lignin–agarose hydrogel and silk fibroin embedded zinc chromite nanoparticles

Given the important aspects of wound healing approaches, in this work, an innovative biocompatible nanobiocomposite scaffold was designed and prepared based on cross-linked lignin–agarose hydrogel, extracted silk fibroin solution, and zinc chromite (ZnCr₂O₄) nanoparticles. Considering the cell viability technique, red blood cell hemolysis in addition to anti-biofilm assays, it was determined that after three days, the toxicity of the cross-linked lignin–agarose/SF/ZnCr₂O₄ nanobiocomposite was less than 13%. Moreover, the small hemolytic effect (1.67%) and high level of prevention in forming a P. aeruginosa biofilm with low OD value (0.18) showed signs of considerable hemocompatibility and antibacterial activity. Besides, according to an in vivo assay study, the wounds of mice treated with the cross-linked lignin–agarose/SF/ZnCr₂O₄ nanobiocomposite scaffold were almost completely healed in five days. Aside from these biological tests, the structural features were evaluated by FT-IR, EDX, FE-SEM, and TG analyses, as well as swelling ratio, rheological, and compressive mechanical study tests. Additionally, it was concluded that adding silk fibroin and ZnCr₂O₄ nanoparticles could enhance the mechanical tensile properties of cross-linked lignin–agarose hydrogel, and also an elastic network was characterized for this designed nanobiocomposite.

Given the important aspects of wound healing approaches, in this work, an innovative biocompatible nanobiocomposite scaffold was designed and prepared based on cross-linked lignin–agarose hydrogel, extracted silk fibroin solution, and zinc chromite (ZnCr₂O₄) nanoparticles.     

Cobalt-modified palladium nanocatalyst on nitrogen-doped reduced graphene oxide for direct hydrazine fuel cell

Nitrogen-doped reduced graphene oxide-supported palladium–cobalt nanoparticles (PdCo NPs/NrGO NSs) are synthesized and used as a high-performance and low-cost anodic catalyst for direct hydrazine–hydrogen peroxide fuel cells. The SEM and TEM images of PdCo NPs/NrGO NSs show the uniform metal nanoparticle distribution on the NrGO NSs. The reduction of the oxygen functional groups and the doping of the nitrogen atoms in the GO framework are confirmed by FT-IR and XRD spectroscopic studies. The Pd catalysts modified by Co exhibit a higher catalytic activity, lower onset potential, better durability, and lower impedance values than unmodified Pd catalysts for the electro-oxidation of hydrazine. The kinetic studies show a first-order reaction with an activation energy of 12.51 kJ mol⁻¹. A direct hydrazine–hydrogen peroxide fuel cell with PdCo NPs/NrGO NSs as anode and Pt/C as cathode provides an open circuit voltage of 1.76 V and a maximum power density of 148.58 mW cm⁻² at 60 °C, indicating that the PdCo NPs/NrGO NSs are an economical, high performance and reliable anode catalyst for the direct hydrazine–hydrogen peroxide fuel cell.

The superior catalytic activity and stability of a novel anodic PdCo NPs/NrGO NSs for HzOR are confirmed by half and signal cell investigations.     

Improved dynamic connection detection power in estimated dynamic functional connectivity considering multivariate dependencies between brain regions

To estimate dynamic functional connectivity (dFC), the conventional method of sliding window correlation (SWC) suffers from poor performance of dynamic connection detection. This stems from the equal weighting of observations, suboptimal time scale, nonsparse output, and the fact that it is bivariate. To overcome these limitations, we exploited the kernel‐reweighted logistic regression (KELLER) algorithm, a method that is common in genetic studies, to estimate dFC in resting state functional magnetic resonance imaging (rs‐fMRI) data. KELLER can estimate dFC through estimating both spatial and temporal patterns of functional connectivity between brain regions. This paper compares the performance of the proposed KELLER method with current methods (SWC and tapered‐SWC (T‐SWC) with different window lengths) based on both simulated and real rs‐fMRI data. Estimated dFC networks were assessed for detecting dynamically connected brain region pairs with hypothesis testing. Simulation results revealed that KELLER can detect dynamic connections with a statistical power of 87.35% compared with 70.17% and 58.54% associated with T‐SWC (p‐value = .001) and SWC (p‐value <.001), respectively. Results of these different methods applied on real rs‐fMRI data were investigated for two aspects: calculating the similarity between identified mean dynamic pattern and identifying dynamic pattern in default mode network (DMN). In 68% of subjects, the results of T‐SWC with window length of 100 s, among different window lengths, demonstrated the highest similarity to those of KELLER. With regards to DMN, KELLER estimated previously reported dynamic connection pairs between dorsal and ventral DMN while SWC‐based method was unable to detect these dynamic connections.