Differentiation of microfluidic-encapsulated trabecular meshwork mesenchymal stem cells into insulin producing cells and their impact on diabetic rats

Tissue and stem cell encapsulation andtransplantation were considered as promising tools in the treatment of patients with diabetes mellitus. The aim of this study was to evaluate the effect of microfluidic encapsulation on the differentiation of trabecular meshwork mesenchymal stem cells (TM-MSC), into insulin-producing cells (IPCs) both in vitro and in vivo. The presence of differentiated cells in microfibers (three dimensional [3D]) and tissue culture plates (TCPS; two dimensional [2D]) culture was evaluated by detecting mRNA and protein expression of pancreatic islet-specific markers as well as measuring insulin release of cells in response to glucose challenges. Finally, semi-differentiated cells in microfibers (3D) and 2D cultures were used to control the glucose level in diabetic rats. The results of this study showed that MSCs differentiated in alginate microfibers (fabricated by microfluidic device) express more Pdx-1 mRNA (1.938-fold, p-value: 0.0425) and Insulin mRNA (2.841-fold, p-value: 0.0001) compared with those cultured on TCPS. Furthermore, cell encapsulation in microfluidic derived microfibers decreased the level of blood glucose in diabetic rats. The approach used in this study showed the possibility of alginate microfibers as a matrix for differentiation of TM-MSCs (as a new source) into IPCs. In addition, it could minimize different steps in stem cell differentiation, handling, and encapsulation, which lead to loss of an unlimited number of cells.     

Role of endogenous cyclo(His-Pro) in cold-induced hypothermia in the desert rat (Mastomys natalensis)

Central administration of exogenous cyclo(His-Pro) (CHP) is known to produce hypothermia in rodents. In the present study, we examined the role of endogenous CHP in cold-induced hypothermia in the desert rat, Mastomys natalensis. The results of these studies show that a rise in hypothalamic CHP content accompanied a decrease in rectal temperature during cold exposure. Immunoneutralization of endogenous CHP resulted in a significant decline in cold-induced hypothermia. In addition, central administration of cyclo(Ala-Gly), a structural analogue of CHP, also led to a decrease in cold-induced hypothermia. The results of these studies show that changes in endogenous CHP levels may affect body temperature regulation.     

Association of Htra1 gene polymorphisms with the risk of developing AMD in Iranian population

Background:

Half of the cases of vision loss in people under 60 years of age have been attributed to age-related macular degeneration (AMD). This is a multifactorial disease with late onset. It has been demonstrated that many different genetic loci are implicated in the risk of developing AMD in different populations. In the current study, we investigated the association of high-temperature ‎requirement A-1 (HTRA1) gene polymorphisms with the risk of developing AMD in the Iranian population.

Methods:

Genomic DNA samples were extracted from 120 patients with AMD and 120 healthy age- and sex-matched controls. A 385 base-pair fragment of the HTRA1 gene promoter region was amplified using the polymerase chain reaction (PCR) technique and sequenced. The frequencies of the alleles were calculated and statistical analysis was performed using SPSS software.

Results:

Our study demonstrated that the rate of polymorphisms rs11200638 -625 G>A and rs2672598 -487T>C were significantly greater in AMD patients than in healthy controls from the Iranian population.

Conclusions:

The results of our study indicate that HTRA1 gene promoter region polymorphisms are associated with the risk of developing AMD in the Iranian population.Key Words: HTRA1, Single Nucleotide Polymorphisms, Macular Degeneration, Iran     

Heterogeneous Determinants of Quality of Life in Different Phenotypes of Parkinson’s Disease

Objectives

Health-related quality of life (HRQoL) is considered a very important outcome indicator in patients with Parkinson’s disease (PD). A broad list of motor and non-motor features have been shown to affect HRQoL in PD, however, there is a dearth of information about the complexity of interrelationships between determinants of HRQoL in different PD phenotypes. We aimed to find independent determinates and the best structural model for HRQoL, also to investigate the heterogeneity in HRQoL between PD patients with different phenotypes regarding onset-age, progression rate and dominant symptom.

Methods

A broad spectrum of demographic, motor and non-motor characteristics were collected in 157 idiopathic PD patients, namely comorbidity profile, nutritional status, UPDRS (total items), psychiatric symptoms (depression, anxiety), fatigue and psychosocial functioning through physical examination, validated questionnaires and scales. Structural equation model (SEM) and multivariate regressions were applied to find determinants of Parkinson’s disease summary index (PDSI) and different domains of HRQoL (PDQ-39).

Results

Female sex, anxiety, depression and UPDRS-part II scores were the significant independent determinants of PDSI. A structural model consisting of global motor, global non-motor and co-morbidity indicator as three main components was able to predict 89% of the variance in HRQoL. In older-onset and slow-progression phenotypes, the motor domain showed smaller contribution on HRQoL and the majority of its effects were mediated through non-motor features. Comorbidity component was a significant determinant of HRQoL only among older-onset and non-tremor-dominant PD patients. Fatigue was not a significant indicator of non-motor component to affect HRQoL in rapid-progression PD.

Conclusions

Our findings showed outstanding heterogeneities in the pattern and determinants of HRQoL among PD phenotypes. These factors should be considered during the assessments and developing personalized interventions to improve HRQOL in PD patients with different phenotypes or prominent feature.     

Sequencing cyclic peptides by multistage mass spectrometry

Some of the most effective antibiotics (e.g. Vancomycin and Daptomycin) are cyclic peptides produced by non-ribosomal biosynthetic pathways. While hundreds of biomedically important cyclic peptides have been sequenced, the computational techniques for sequencing cyclic peptides are still in their infancy. Previous methods for sequencing peptide antibiotics and other cyclic peptides are based on Nuclear Magnetic Resonance spectroscopy, and require large amount (miligrams) of purified materials that, for most compounds, are not possible to obtain. Recently, development of MS-based methods has provided some hope for accurate sequencing of cyclic peptides using picograms of materials. In this paper we develop a method for sequencing of cyclic peptides by multistage MS, and show its advantages over single-stage MS. The method is tested on known and new cyclic peptides from Bacillus brevis, Dianthus superbus and Streptomyces griseus, as well as a new family of cyclic peptides produced by marine bacteria.     

Detection and characterisation of a phytoplasma associated with cucumber (Cucumis sativus) regional yellows disease in Iran

Abstract

A phytoplasma was detected in cucumber (Cucumis sativus), exhibiting regional yellows symptoms in leaves, stem and fruits, that was grown in the greenhouse near Tehran (Iran). Since this is a previously undescribed disease, the name cucumber regional yellows have been tentatively assigned to it. Based on in silico RFLP and phylogenetic analysis of PCR-amplified 16S rDNA sequences, the phytoplasma associated with regional yellows disease was identified as a new member of phytoplasma 16S rRNA group VI (16SrVI-A) with closest relationships to zucchini phyllody phytoplasma (KP119494). According to our results, cucumber regional yellows phytoplasma could be designated as a subgroup VI-A.     

Growth,Physiological and Biochemical Traits of Sage under the Exogenous Stimulating and Stress Factors

Russian Journal of Plant Physiology - Sage (Salvia officinalis L.) belonging to the Lamiaceae family, as the main herb in the world is cultivated in many countries for extraction of essential oil...     

Analytical Approach to the Surface Plasmon Resonance Characteristic of Metal Nanoparticle Dimer in Dipole-Dipole Approximation

This theoretical study deals with the effect of bi-particle interaction on the surface plasmon resonance (SPR) in a dimer which includes two identical metal nanoparticles (NPs). Considering the dipole-dipole interaction in a Drude-like model, an appropriate equation is derived for the permittivity of each NP. The restoration force related to the classical confinement originating from the finite size of NPs is considered, and an appropriate adjustment coefficient is considered for this term through analyzing experimental data. Two different polarizations are considered for the laser beam electric field, and it is shown that the orientation of the electric field has an essential role in the linear optical properties of a dimer. Numerical investigation is accomplished for a dimer of gold NPs with two different diameters of 4 nm and 20 nm. For the parallel polarization, dipole-dipole interaction leads to the redshift of SPR wavelength and increase in its peak value, while for the perpendicular polarization, the absolute opposite results are derived. For all cases, it is shown that SPR wavelength functionality with respect to the geometric factor a/d (NP radius to the separation) can be presented by a cubic equation that fits better than an exponential one suggested by the earlier studies which demonstrates the dipole-dipole characteristic of the interaction. Qualitatively, our results are in good agreement with the other experimental studies.