Synthesis of magnetic chitosan/hyaluronic acid/κ-carrageenan nanocarriers for drug delivery.

The magnetic nanocarriers containing chitosan/hyaluronic acid complexed with κ-carrageenan were synthesized by solution method, as the drug delivery system. Doxorubicin (DOX) was used as the model drug. Characterization assessments were performed to identify the functional groups, determine the structure and morphology, and magnetic properties of nanodelivery system. Furthermore, their impacts on MCF-7 and MDA-MB-237 cell lines were evaluated by MTT assay. Analyses confirm polymers physical interaction, chemical bonding in the structure, moreover presence of spherical shape magnetic nanoparticles in the 100-150 nm range. The DOX loading was 74.1 ± 2.5 %. Results indicate that the drug loading was raised to 83.0±2.2 % by increasing the amount of κ-carrageenan in specimens. The swelling of samples in the acidic environment (e.g. pH 5.5) was verified by the Dynamic Light Scattering analysis. Consequently, pH stimulus-responsive drug release in the sustained stream and a considerable amount of DOX release (84±3.1 %) was detected as compared to a higher pH medium (27±1.5 % at pH 7.4). According to the MTT assay results, MNPs showed no inhibitory effect on both cell lines. Also, 10 and 15 µg/ml of MNPs-DOX was considered as IC50 value on MDA-MB-237 and MCF-7 cells, respectively. The DOX 25 µg/ml caused 50 % antiproliferative activity in both cell lines.

Socioeconomic and environmental determinants of foot and mouth disease incidence: an ecological, cross-sectional study across Iran using spatial modeling.

Foot-and-mouth disease (FMD) is a highly contagious animal disease caused by a ribonucleic acid (RNA) virus, with significant economic costs and uneven distribution across Asia, Africa, and South America. While spatial analysis and modeling of FMD are still in their early stages, this research aimed to identify socio-environmental determinants of FMD incidence in Iran at the provincial level by studying 135 outbreaks reported between March 21, 2017, and March 21, 2018. We obtained 46 potential socio-environmental determinants and selected four variables, including percentage of population, precipitation in January, percentage of sheep, and percentage of goats, to be used in spatial regression models to estimate variation in spatial heterogeneity. In our analysis, we employed global models, namely ordinary least squares (OLS), spatial error model (SEM), and spatial lag model (SLM), as well as local models, including geographically weighted regression (GWR) and multiscale geographically weighted regression (MGWR). The MGWR model yielded the highest adjusted [Formula: see text] of 90%, outperforming the other local and global models. Using local models to map the effects of environmental determinants (such as the percentage of sheep and precipitation) on the spatial variability of FMD incidence provides decision-makers with helpful information for targeted interventions. Our findings advocate for multiscale and multidisciplinary policies to reduce FMD incidence.

Long-term biological hydrogen production by agar immobilized Rhodobacter capsulatus in a sequential batch photobioreactor.

In this study, agar immobilization technique was employed for biological hydrogen production using Rhodobacter capsulatus DSM 1710 (wild type) and YO3 (hup-mutant) strains in sequential batch process. Different agar and glutamate concentrations were tested with defined nutrient medium. Agar concentration 4% (w/v) and 4 mM glutamate were selected for bacterial immobilization in terms of rate and longevity of hydrogen production. Acetate concentration was increased from 40 to 60-100 and 60 mM gave best results with both bacterial strains immobilized in 4% (w/v) agar. Cell concentration was increased from 2.5 to 5 mg dcw mL-1 agar and it was found that increasing cell concentration of wild-type strain caused decrease in yield and productivity while these parameters improved by increasing cell concentration of mutant strain. Also, the hydrogen production time has extended from 17 days up to 60 days according to the process conditions and parameters. Hydrogen production by immobilized photosynthetic bacteria is a convenient technology for hydrogen production as it enables to produce hydrogen with high organic acid concentrations comparing to suspended cultures. Besides, immobilization increases the stability of the system and allowed sequential batch operation for long-term application.