Micromechanics fracture in osteonal cortical bone: a study of the interactions between microcrack propagation, microstructure and the material properties

A two-dimensional micromechanical fibre reinforced composite materials model for osteonal cortical bone is presented. The interstitial bone is modelled as a matrix, the osteons are modelled as fibres, and the cement line is presented as interface tissue. The interaction between osteons and microcracks is evaluated by linear elastic fracture mechanics theory, followed by a determination of the stress intensity factor at the vicinity of the microcrack tips. The results indicate that bone microstructural heterogeneity greatly influences fracture parameters. Furthermore, microstructural morphology and loading conditions affect growth trajectories, the microcrack propagation trajectory deviates from the osteon under tensile loading, and osteon penetration is observed under compressive loads.     

Exosomes and microRNAs: New potential therapeutic candidates in Alzheimer disease therapy

Exosomes are biological nanocarriers which could be involved in a variety of basic physiological events. They exert their effects via targeting their cargos (i.e., DNAs, messenger RNAs, microRNAs [miRNAs], and proteins) to host cells, which led to change behaviors of recipient cells. One of the important aspects of exosomes is the roles of them in disease conditions. Increasing evidence indicated that exosomes are one of the main players in Alzheimer’s disease (AD) pathogenesis. Hence, it seems that these nanocarriers could be used as diagnostic and therapeutic biomarkers in AD treatment. Another important player in AD pathogenesis is miRNA. MiRNAs are short noncoding RNAs which exert their effects as epigenetic regulators. These molecules involved in different stages of AD. Therefore, miRNAs could be used as prognostic, diagnostic, and therapeutic biomarkers in AD. Here, we summarized various roles of exosomes and application of them in AD pathogenesis. Moreover, we highlighted the utilization of miRNAs as a therapeutic option in AD therapy.     

ARA lncRNA,is upregulated in liver and breast tumor tissues

Molecular Biology Reports - Important regulatory roles of long non-coding RNAs (lncRNAs) have been recently found, and reported as useful biomarkers in cancer. To identify a potential expression of...     

Effect of chronic lithium administration on endothelium-dependent relaxation of rat mesenteric bed: role of nitric oxide

The mechanism of action of lithium, an effective treatment for bipolar disease, is still unknown. In this study, the mesenteric vascular beds of control rats and rats that were chronically treated with lithium were prepared by the McGregor method, and the mesenteric vascular bed vasorelaxation responses were examined. NADPH-diaphorase histochemistry was used to determine the activity of NOS (nitric oxide synthase) in mesenteric vascular beds. We demonstrated that ACh-induced vasorelaxation increased in the mesenteric vascular bed of rats treated with lithium. Acute No-nitro-L-arginine methyl ester (L-NAME) administration in the medium blocked ACh-induced vasorelaxation in the control group more effectively than in lithium-treated rats, while the vasorelaxant response to sodium nitroprusside, a NO donor, was not different between lithium-treated and control groups. Acute aminoguanidine administration blocked ACh-induced vasorelaxation of lithium-treated rats, but had no effect in the control rats. Furthermore, NOS activity, determined by NADPH-diaphorase staining, was significantly greater in the mesenteric vascular beds from chronic lithium-treated rats than in those from control rats. These data suggest that the enhanced ACh-induced endothelium-derived vasorelaxation in rat mesenteric bed from chronic lithium-treated rats might be associated with increased NOS activity, likely via iNOS. Simultaneous acute L-NAME and indomethacin administration suggests the possible upregulation of EDHF (endothelium-derived hyperpolarizing factor) in lithium-treated rats.     

The anti-cancer effect of amygdalin on human cancer cell lines

Derived from rosaceous plant seed, amygdalin belongs to aromatic cyanogenic glycoside group, and its anticancer effects have been supported by mounting evidence. In this study, we objected to investigate amygdalin effect on two antiapoptotic genes (Survivin, XIAP) and two lncRNAs (GAS5, MALAT1) in human cancer cells (A549, MCF7, AGS). Employing RT-qPCR analysis, we compared the mRNA levels of the genes related to apoptosis in A549, MCF7, and AGS cancer cells between amygdalin-treated (24, 48 and 72 h) and un-treated groups. RNA was extracted from both cell groups and then cDNAs were synthesized. The changes in the gene expression levels were specified using ΔΔCt method. RT-qPCR analysis has revealed that the expression of Survivin, XIAP, GAS5 and MALAT1 in amygdala-treated cancer cells were significantly different, compared to the un-treated cells. However, these expressions were different depending on the treatment time. According to the results, amygdalin significantly inhibited the expression level of Survivin, and XIAP genes in treated via untreated group. Our findings suggest that amygdalin might have an anticancer effect due to the various gene expressions in A549, MCF7, and AGS human cancer cells, showing it’s potential as a natural therapeutic anticancer drug.

     

Bleeding disorders in the tribe: result of consanguineous in breeding

Objective

To determine the frequency and clinical features of bleeding disorders in the tribe as a result of consanguineous marriages.

Design

Cross Sectional Study

Introduction

Countries in which consanguinity is a normal practice, these rare autosomal recessive disorders run in close families and tribes. Here we describe a family, living in village Ali Murad Chandio, District Badin, labeled as haemophilia.

Patients & Methods

Our team visited the village & developed the pedigree of the whole extended family, up to seven generations. Performa was filled by incorporating patients, family history of bleeding, signs & symptoms, and bleeding from any site. From them 144 individuals were screened with CBC, bleeding time, platelet aggregation studies & RiCoF. While for PT, APTT, VWF assay and Factor VIII assay, samples were kept frozen at -70 degrees C until tested.

Results

The family tree of the seven generations comprises of 533 individuals, 63 subjects died over a period of 20 years and 470 were alive. Out of all those 144 subjects were selected on the basis of the bleeding history. Among them 98(68.1%) were diagnosed to have a bleeding disorder; 44.9% patients were male and 55.1% patients were female. Median age of all the patients was 20.81, range (4 months- 80 yrs). The results of bleeding have shown that majority had gum bleeding, epistaxis and menorrhagia. Most common bleeding disorder was Von Willebrand disease and Platelet functional disorders.

Conclusion

Consanguineous marriages keep all the beneficial and adversely affecting recessive genes within the family; in homozygous states. These genes express themselves and result in life threatening diseases. Awareness, education & genetic counseling will be needed to prevent the spread of such common occurrence of these bleeding disorders in the community.     

Effect of CaCl2 on growth performance, photosynthetic efficiency and nitrogen assimilation of Cichorium intybus L. grown under NaCl stress

Pot culture experiments were conducted to assess the extent of growth, photosynthetic efficiency and nitrogen assimilation of chicory (Cichorium intybus L.) as affected by NaCl and CaCl₂ alone as well as in combination. Six treatments, i.e., 80 mM and 160 mM NaCl, 5 mM and 10 mM CaCl₂ and 80 mM + 10 mM and 160 mM + 10 mM of NaCl + CaCl₂ were given to the growing plants separately at three developmental stages, viz., the pre-flowering (30 DAS), flowering (120 DAS) and post-flowering (150 DAS) stages. Each NaCl treatment caused a significant reduction in total plant biomass, photosynthetic rate, stomatal conductance, total chlorophyll content, soluble protein content, NR activity and nitrogen content, although nitrate content increased. On the contrary CaCl₂ treatment gave a favorable effect, compared to the control. The effect of combined treatments was similar to that of NaCl but less in magnitude. Thus, the application of CaCl₂ may mitigate the adverse effect caused by NaCl.