Effect of Leukemia Inhibitory Factor on the Myelinogenic Ability of Schwann-Like Cells Induced from Human Adipose-Derived Stem Cells

The Schwann cells (SCs) may be obtain from nerve biopsies for autologous transplantation. However, it is difficult to obtain sufficient amount of SCs for clinical applications. Human adipose-derived stem cells (ADSCs) can be induced to differentiate into Schwann-like cells (S-like cells) and used for autologous transplantation. However, effect of leukemia inhibitory factor (LIF) on the myelinogenic ability of SC-like cells induced from human ADSC is not investigated yet. The aim of this study was to evaluate of the effect of exogenous LIF on myelinogenic potential of differentiated cells in vitro. ADSCs were harvested from human fat tissue and characterized using flow cytometry. Human ADSCs were treated for sphere formation and LIF was added to terminal differentiation medium. GFAP/S100β and MBP markers were used to confirm differentiation of human ADSCs, and myelinogenic ability of SC-like cells, respectively, using both immunostaining and real-time RT-PCR analysis. The analysis for GFAP⁺/S100β⁺ revealed that LIF can increase both differentiated cells rates and the percentage of myelinating SC-like cells (p < 0.05). Our data showed that SC-like cells induced from human ADSCs were able to generate myelin when exposed to LIF and these cells could be a potential source for the treatment of peripheral and central axonal injuries.     

Pattern of infection and antibiotic activity among Streptococcus agalactiae isolates from adults in Mashhad,Iran

Background:

One of the main causes of sexually transmitted diseases is group B β- hemolytic streptococci (GBS) multiplying in the genital tracts. Penicillin is the most common drug for the treatment of infections caused by these bacteria, but in patients suffering from Penicillin allergy, Erythromycin and Clindamycin are used as alternative therapeutic drugs against GBS. Recently, resistance to these drugs has been reported more often. In this study, efforts have been made to determine the prevalence and antibiotic resistance of GBS.

Methods:

Modified Christie Atkins Munch-Petersen (CAMP) test was conducted on over 2400 samples of urine and discharge taken from vagina, urethra and prostate. The drug sensitivity was performed by double disk sensitivity tests to Bacitracin, Trimethoprim, and Sulfamethoxazole and then the resistant samples were investigated by E-test to determine the minimal inhibitory concentrations (MICs) value.

Results:

Twenty-three vaginal and 10 urethral discharge, 27urine and 6 prostatic secretion samples were GBS positive. The most symbiotic microorganisms with GBS were strains of Enterococci (90%), Staphylococcus saprophyticus (25%) and Candida albicans (6%). The disk diffusion method showed 18 cases with Penicillin resistance (MIC: 1.5 mg/ml).

Conclusion:

Taken together, GBS carriers’ rate in this study was found 20.65% (8.24% men and 12.4% women). Furthermore, findings showed high-level resistance to Erythromycin and Clindamycin.Key Words: Antibiotic resistance, Genitourinary system, Streptococcus agalactiae, minimal inhibitory concentration (MIC)     

Opportunism: a panacea for implementation of whole-genome sequencing studies in nutrigenomics research?

Observational studies have consistently shown associations between mild deficiencies in folate and vitamin B₁₂ with increased risk of a myriad of common diseases. These findings have invariably translated into null outcomes in intervention trials due in part to our ignorance of the specific genomic and environmental factors that underpin population variability in requirements to these B-vitamins. Although genome-wide association studies have shed initial light on the genetic architecture of variability in status of these vitamins, particularly vitamin B₁₂, the causal mechanisms remain uncharacterised. A recent study by Grarup et al. (PLoS Genet 9(6):e1003530, 2013) used next-generation whole-genome sequencing to gain further insight into the genetic architecture of vitamin B₁₂ and folate status in the general population. Their study represents the analysis of approximately ten times greater number of genetic variants and nearly four times the number of individuals compared to the largest previous GWAS study of these B-vitamins. In light of this, we purport that although the study may be viewed as the state of the art in the roadmap to personalised or precision nutrition, the lack of insight provided by the study serves as a cautionary reminder of the importance of study design, particularly when leveraging large-scale data, such as those from whole-genome sequences. We believe that the precedent set by such large-scale “proof of principle” type projects will wrongly enforce a negative outlook for nutrigenomics research and present alternative study designs, which although less opportunistic are far more likely to be informative and yield novel results.     

Rheumatoid Arthritis Susceptibility Is Associated with the KIR2DS4-Full of Killer-Cell Immunoglobulin-Like Receptor Genes in the Lur Population of Iran

Background:The pathophysiology underlying the progression and development of autoimmune conditions, such as Rheumatoid Arthritis (RA), is a result of dysregulations of the immune system. Research has explored the genetic alterations present in RA; however, limited studies have examined the role of Killer cell Immunoglobulin-like Receptors (KIR) and Human Leukocyte Antigen (HLA) molecules in RA. Therefore, the aim of this study was to examine KIR genes, their HLA ligands, and KIR-HLA compounds in patients with RA.Methods:In this case-control study, a total of 50 patients with RA and 100 healthy individuals were enrolled. DNA samples were evaluated using PCR with sequence specific Primers (PCR-SSP). Odds ratio (OR) with a 95% confidence interval (CI) were reported.Results:Among the KIR genes examined, KIR2DLA (p= 0.0255, OR= 0.389, 95% CI= 0.210-0.722) and KIR2DS4-full (p< 0.0001, OR= 6.163, 95% CI= 3.174-11.968) were observed to have a statistically significant correlation with disease susceptibility to RA. As an inhibitory gene, KIR2DLA was observed to have a protective effect against RA while KIR2DS4-full as an activating gene, was found to increase risk for RA. No significant associations were found between any of the other KIR genotypes, HLA ligands, or KIR-HLA compounds examined in this study to RA susceptibility. Conclusion:In this study of RA in the Lur population of Iran, KIR2DS4-full was observed to increase susceptibility to RA, while KIR2DL5A was found to act as a protecting factor based on both the cross Table and regression analyses. Further research should focus on repeating this study in additional populations.Key Words: HLA, KIR, NK cells, Rheumatoid Arthritis     

Numerical simulation of wave propagation in a realistic model of the human external ear

In this study, a numerical investigation is performed to evaluate the effects of high-pressure sinusoidal and blast wave's propagation around and inside of a human external ear. A series of computed tomography images are used to reconstruct a realistic three-dimensional (3D) model of a human ear canal and the auricle. The airflow field is then computed by solving the governing differential equations in the time domain using a computational fluid dynamics software. An unsteady algorithm is used to obtain the high-pressure wave propagation throughout the ear canal which is validated against the available analytical and numerical data in literature. The effects of frequency, wave shape, and the auricle on pressure distribution are then evaluated and discussed. The results clearly indicate that the frequency plays a key role on pressure distribution within the ear canal. At 4 kHz frequency, the pressure magnitude is much more amplified within the ear canal than the frequencies of 2 and 6 kHz, for the incident wave angle of 90° investigated in this study, attributable to the ‘4-kHz notch’ in patients with noise-induced hearing loss. According to the results, the pressure distribution patterns at the ear canal are very similar for both sinusoidal pressure waveform with the frequency of 2 kHz and blast wave. The ratio of the peak pressure value at the eardrum to that at the canal entrance increases from about 8% to 30% as the peak pressure value of the blast wave increases from 5 to 100 kPa for the incident wave angle of 90° investigated in this study. Furthermore, incorporation of the auricle to the ear canal model is associated with centerline pressure magnitudes of about 50% and 7% more than those of the ear canal model without the auricle throughout the ear canal for sinusoidal and blast waves, respectively, without any significant effect on pressure distribution pattern along the ear canal for the incident wave angle of 90° investigated in this study.     

Harnessing an Integrative In Silico Approach to Engage Highly Immunogenic Peptides in an Antigen Design Against Epsilon Toxin (ETX) of Clostridium perfringens

International Journal of Peptide Research and Therapeutics - Epsilon toxin (ETX) is one of four lethal toxins of Clostridium perfringens produced by types B and D of the pathogen. This pore-forming...     

Prevalence of cytomegalovirus infection and its role in total immunoglobulin pattern in Iranian patients with different subtypes of multiple sclerosis

Multiple sclerosis (MS) is the most common autoimmune disease characterized by multifocal areas of inflammatory demyelination within the central nervous system. Cytomegalovirus (CMV) has a complex pathobiology and in most cases is simply asymptomatic. There is some recent controversy over the role of CMV in the pathology of MS. The aim of this study was to evaluate active CMV infection and its effect on the humoral immunity in patients with MS. Serum, plasma, peripheral blood mononuclear cells (PBMCs), saliva and urine collected from MS patients (n=78) and healthy subjects (n=123) were screened for the presence of anti-CMV antibodies and CMV-DNA by nephelometric and PCR methods. Concentrations of total antibodies in MS subtypes were measured using both nephelometric and enzyme linked fluorescent assay (ELFA) techniques. The results extend the observation of an increased frequency of CMV-DNA in patients, in contrast with controls (p<0.001). Furthermore, systemic CMV infections were found in 25.5% of patients and only 3.2% of controls (p<0.001). There was significant difference in the titers of anti-CMV IgG and total IgE in patient and controls (P<0.001). These results support the hypothesis that CMV may contribute to MS thought to establish systemic infection process and induce immune response.