Autologous transplantation of CD34+ bone marrow derived mononuclear cells in management of non-reconstructable critical lower limb ischemia

Patients with a decrease in limb perfusion with a potential threat to limb viability manifested by ischemic rest pain, ischemic ulcers, and/or gangrene are considered to have critical limb ischemia (CLI). Because of this generally poor outcome, there is a strong need for attempting any procedure to save the affected limb. The aim of this work is to evaluate the possibility to use stem cell therapy as a treatment option for patients with chronic critical lower limb ischemia with no distal run off. This study includes 20 patients with chronic critical lower limb ischemia with no distal run off who are unsuitable for vascular or endovascular option. These patients underwent stem cell therapy (SCT) by autologous transplantation of bone marrow derived mononuclear cells. 55 % of patients treated with SCT showed improvement of the rest pain after the first month, 60 % continued improvement of the rest pain after 6 months, 75 % after 1 year and 80 % after 2 years and continued without any deterioration till the third year. Limb salvage rate after STC was 80 % after the first year till the end of the second and third years. SCT can result in angiogenesis in patients with no-option CLI, providing a foundation for the application of this therapy to leg ischemia.     

Flow injection amperometric detection of insulin at cobalt hydroxide nanoparticles modified carbon ceramic electrode

Cobalt hydroxide nanoparticles were prepared onto a carbon ceramic electrode (CHN|CCE) using the cyclic voltammetry (CV) technique. The modified electrode was characterized by X-ray diffraction and scanning electron microscopy. The results showed that CHN with a single-layer structure was uniformly electrodeposited on the surface of CCE. The electrocatalytic activity of the modified electrode toward the oxidation of insulin was studied by CV. CHN|CCE was also used in a homemade flow injection analysis system for insulin determination. The limit of detection (signal/noise [S/N] = 3) and sensitivity were found to be 0.11 nM and 11.8 nA/nM, respectively. Moreover, the sensor was used for detection of insulin in human serum samples. This sensor showed attractive properties such as high stability, reproducibility, and high selectivity.     

Weeds ability to phytoremediate cadmium-contaminated soil

An alternative method to other technologies to clean up the soil, air and water pollution by heavy metals is phytoremediation. Therefore, a pot culture experiment was conducted at the College of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran, in 2014 to determine the potential absorption of cadmium by Portulaca oleracea (Common purslane), Solanum nigrum (Black nightshade), Abutilon theophrasti (Velvetleaf) and Taraxacum officinale (Dandelion). The type of experiment was completely randomized design with factorial arrangement and four replications. The soil in pot was treated with different rates of CdCl₂.H₂O (0 (control), 10, 20, 40, 60, and 80 mg Cd/kg soil) and the plants were sown. With increasing concentration levels, fresh weight and dry weight of shoots and roots of all plant species were reduced. The reduction severity was ranked according the following order, P. oleracea > A. theophrasti > S. nigrum > T. officinale. Bioconcentration factor (BCF), Translocation factor (TF) and Translocation efficiency (TE%) was ranked according the following order, T. officinale > S. nigrum > A. theophrasti > P. oleracea. The results of this study revealed that T. officinale and S. nigrum are effective species to phytoremediate Cd-contaminated soil.     

Design,Optimization, and Evaluation of a Novel Metronidazole-Loaded Gastro-Retentive pH-Sensitive Hydrogel

Floating pH-sensitive chitosan hydrogels containing metronidazole were developed for the eradication of Helicobacter pylori from the stomach. Hydrogels were prepared by crosslinking medium or high molecular weight chitosan in lyophilized solutions containing metronidazole using either citrate or tripolyphosphate (TPP) salts at 1% or 2% concentration. A 2³ factorial design was developed to study the influence of formulation parameters on the physical characteristics of the prepared hydrogels. The interaction between hydrogel components was investigated. The morphology of the prepared hydrogels was inspected and their percentage swelling, release pattern, and moisture content were evaluated. The results revealed the absence of interaction between hydrogel components and their highly porous structure. Percentage swelling of the hydrogels was much higher, and drug release was faster in gastric pH compared with intestinal pH. The formula prepared using 2% high molecular weight chitosan and 2% TPP significantly swelled (700%) within the first 4 h and released the loaded drug over a period of 24 h. Its moisture content was not affected by storage at high relative humidity. Therefore, this formula was selected to be tested in dogs for its gastric retention (using X-ray radiography) and efficacy in the eradication of H. pylori (using histopathological and microbiological examination). The results revealed that the prepared hydrogel formula was retained in dog stomach for at least 48 h, and it was more effective against H. pylori than the commercially available oral metronidazole tablets (Flagyl®).     

Inferring Population Size History from Large Samples of Genome-Wide Molecular Data - An Approximate Bayesian Computation Approach

Inferring the ancestral dynamics of effective population size is a long-standing question in population genetics, which can now be tackled much more accurately thanks to the massive genomic data available in many species. Several promising methods that take advantage of whole-genome sequences have been recently developed in this context. However, they can only be applied to rather small samples, which limits their ability to estimate recent population size history. Besides, they can be very sensitive to sequencing or phasing errors. Here we introduce a new approximate Bayesian computation approach named PopSizeABC that allows estimating the evolution of the effective population size through time, using a large sample of complete genomes. This sample is summarized using the folded allele frequency spectrum and the average zygotic linkage disequilibrium at different bins of physical distance, two classes of statistics that are widely used in population genetics and can be easily computed from unphased and unpolarized SNP data. Our approach provides accurate estimations of past population sizes, from the very first generations before present back to the expected time to the most recent common ancestor of the sample, as shown by simulations under a wide range of demographic scenarios. When applied to samples of 15 or 25 complete genomes in four cattle breeds (Angus, Fleckvieh, Holstein and Jersey), PopSizeABC revealed a series of population declines, related to historical events such as domestication or modern breed creation. We further highlight that our approach is robust to sequencing errors, provided summary statistics are computed from SNPs with common alleles.     

Campylobacter jejuni outer membrane vesicle‐associated proteolytic activity promotes bacterial invasion by mediating cleavage of intestinal epithelial cell E‐cadherin and occludin

Outer membrane vesicles (OMVs) play an important role in the pathogenicity of Gram‐negative bacteria. Campylobacter jejuni produces OMVs that trigger IL‐8, IL‐6, hBD‐3 and TNF‐α responses from T84 intestinal epithelial cells and are cytotoxic to Caco‐2 IECs and Galleria mellonella larvae. Proteomic analysis of 11168H OMVs identified the presence of three proteases, HtrA, Cj0511 and Cj1365c. In this study, 11168H OMVs were shown to possess proteolytic activity that was reduced by pretreatment with specific serine protease inhibitors. OMVs isolated from 11168H htrA, Cj0511 or Cj1365c mutants possess significantly reduced proteolytic activity. 11168H OMVs are able to cleave both E‐cadherin and occludin, but this cleavage is reduced with OMVs pretreated with serine protease inhibitors and also with OMVs isolated from htrA or Cj1365c mutants. Co‐incubation of T84 monolayers with 11168H OMVs results in a visible reduction in both E‐cadherin and occludin. The addition of 11168H OMVs to the co‐culture of live 11168H bacteria with T84 cells results in enhanced levels of bacterial adhesion and invasion in a time‐dependent and dose‐dependent manner. Further investigation of the cleavage of host cell structural proteins by C. jejuni OMVs should enhance our understanding of the interactions of this important pathogen with intestinal epithelial cells.     

The combination of dimethoxycurcumin with DNA methylation inhibitor enhances gene re-expression of promoter-methylated genes and antagonizes their cytotoxic effect

Curcumin and its analogs exhibited antileukemic activity either as single agent or in combination therapy. Dimethoxycurcumin (DMC) is a more metabolically stable curcumin analog that was shown to induce the expression of promoter-methylated genes without reversing DNA methylation. Accordingly, co-treatment with DMC and DNA methyltransferase (DNMT) inhibitors could hypothetically enhance the re-expression of promoter-methylated tumor suppressor genes. In this study, we investigated the cytotoxic effects and epigenetic changes associated with the combination of DMC and the DNMT inhibitor decitabine (DAC) in primary leukemia samples and cell lines. The combination demonstrated antagonistic cytotoxic effects and was minimally cytotoxic to primary leukemia cells. The combination did not affect the metabolic stability of DMC. Although the combination enhanced the downregulation of nuclear DNMT proteins, the hypomethylating activity of the combination was not increased significantly compared to DAC alone. On the other hand, the combination significantly increased H3K27 acetylation (H3K27Ac) compared to the single agents near the promoter region of promoter-methylated genes. Furthermore, sequential chromatin immunoprecipitation (ChIP) and DNA pyrosequencing of the chromatin-enriched H3K27Ac did not show any significant decrease in DNA methylation compared to other regions. Consequently, the enhanced induction of promoter-methylated genes by the combination compared to DAC alone is mediated by a mechanism that involves increased histone acetylation and not through potentiation of the DNA hypomethylating activity of DAC. Collectively, our results provide the mechanistic basis for further characterization of this combination in leukemia animal models and early phase clinical trials.