Association of Genetic Structure and Diversity in Iranian Wild Germplasms of Mentha longifolia L. Based on Phenotypical,Biochemical, and Molecular Markers

Mentha longifolia L. is well-known to be one of the most pervasive wild-growing species of the Lamiaceae family, which has extensive beneficial properties in the fields of pharmacology and biological products. In the present study, the correlation between Inter-simple sequence repeat (ISSR) markers and morpho-chemical parameters of twenty different M. longifolia accessions (MLACs) were assessed. The geographic information system (GIS) has been employed to interpret the original habitat of the accessions in Iran. ISSR analysis indicated a remarkable difference in the studied accessions, segregated them into three main groups, constructed by an unweighted pair-group method with arithmetic (UPGMA) and principal coordinate analysis (PCoA). A total of 89 bands were generated by 12 ISSR primers, among which 82 (91.97 %) of them were polymorphic. The cluster analysis based on agro-morphological data scattered MLACs into two main groups. The essential oils (EOs) were analyzed through GC/FID/MS, and four chemotypes were characterized according to the major constituents. Pulegone ranged from 0.17 to 69.50 % was the main oil constituent with the highest content. Also, HPLC-PDA was employed to identify and to quantify the phenolic compounds in the MeOH extracts of MLACs. Heatmap cluster based on phenolic compounds produced three main categories of accessions. The components identified in the extracts were rosmarinic acid, rutin, vanillic acid, ferulic acid, chlorogenic acid, caffeic acid, 3,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, and p-coumaric acid, which among them rosmarinic acid (RA) varied from 39.16 to 261.55 mg/100 g (DW) as a predominant constituent. Subsequently, multiple regression analyses between ISSR fragments and morpho-chemical data illustrated considerable relationships in the plant materials. The high variation and correlation observed in metabolic and phenotypic traits of MLACs establish an adequate source to conduct reserves conservation programs.     

Resistance to radial expansion limits muscle strain and work

The collagenous extracellular matrix (ECM) of skeletal muscle functions to transmit force, protect sensitive structures, and generate passive tension to resist stretch. The mechanical properties of the ECM change with age, atrophy, and neuromuscular pathologies, resulting in an increase in the relative amount of collagen and an increase in stiffness. Although numerous studies have focused on the effect of muscle fibrosis on passive muscle stiffness, few have examined how these structural changes may compromise contractile performance. Here we combine a mathematical model and experimental manipulations to examine how changes in the mechanical properties of the ECM constrain the ability of muscle fibers and fascicles to radially expand and how such a constraint may limit active muscle shortening. We model the mechanical interaction between a contracting muscle and the ECM using a constant volume, pressurized, fiber-wound cylinder. Our model shows that as the proportion of a muscle cross section made up of ECM increases, the muscle’s ability to expand radially is compromised, which in turn restricts muscle shortening. In our experiments, we use a physical constraint placed around the muscle to restrict radial expansion during a contraction. Our experimental results are consistent with model predictions and show that muscles restricted from radial expansion undergo less shortening and generate less mechanical work under identical loads and stimulation conditions. This work highlights the intimate mechanical interaction between contractile and connective tissue structures within skeletal muscle and shows how a deviation from a healthy, well-tuned relationship can compromise performance.     

Biomimetic polysaccharide nanocomposites of high cellulose content and high toughness

Plant cell walls combine mechanical stiffness, strength and toughness despite a highly hydrated state. Inspired by this, a nanostructured cellulose network is combined with an almost viscous polysaccharide matrix in the form of a 50/50 amylopectin-glycerol blend. Homogeneous films with a microfibrillated cellulose (MFC) nanofiber content in the range of 10-70 wt % are successfully cast. Characterization is carried out by dynamic mechanical analysis, field-emission scanning electron microscopy, X-ray diffraction, and mercury density measurements. The MFC is well dispersed and predominantly oriented random-in-the-plane. High tensile strength is combined with high modulus and very high work of fracture in the nanocomposite with 70 wt % MFC. The reasons for this interesting combination of properties include nanofiber and matrix properties, favorable nanofiber-matrix interaction, good dispersion, and the ability of the MFC network to maintain its integrity to a strain of at least 8%.     

Association between TPO gene polymorphisms and Anti-TPO level in Tehranian population: TLGS

Introduction

Thyroid peroxidase (TPO) gene variations are one cause of thyroid autoimmune diseases. The aim of this study was to examine the association between the T1936C, T2229C and A2257C polymorphisms of the TPO gene and Anti-TPO level.

Materials and methods

In this case–control study, 188 individuals (86 males and 102 females), aged 20–80 years, were randomly selected from among the Tehran Lipid and Glucose Study (TLGS) population. A2257C and T2229C SNPs were detected with RFLP by use of BsrI and Eco57I as the restriction enzymes respectively, while the T1936C SNP was determined with ARMS-PCR.

Results

In the presence of the C allele of T1936C, Anti-TPO level was significantly increased (CC: 238 ± 43.3, CT: 47.7 ± 15.9, TT: 74.1 ± 11.3 IU/L p = 0.002); however, this association was attenuated after adjustment for sex and age (p = 0.059). No significant difference, before and after adjustment, was found in Anti-TPO level in the presence of T2229C SNP (CC: 129.1 ± 24.5, CT: 43.5 ± 12.6, TT: 126.5 ± 13.8 IU/L p = 0.196). The association between A2257C and Anti-TPO level was only significant after adjustment for potential confounders (p = 0.007). The association between ATC and CTT haplotypes and Anti-TPO level was significant (p = 0.023, 0.021 respectively), the association between CTT and Anti-TPO concentration was also significant after adjustment for sex (p = 0.014).

Conclusion

The results of the present study confirmed the association between TPO gene polymorphisms and Anti-TPO level in the Tehranian population.     

In vivo induction of necrosis in mice fibrosarcoma via intravenous injection of type B staphylococcal enterotoxin

The bacterial superantigen staphylococcal enterotoxin B (SEB) is a potent inducer of cytotoxic T-cell activity and cytokine production in vivo. We investigated the possibility of the therapeutic application of SEB in patients with fibrosarcoma. The anti-tumor effect of SEB in mice with inoculated fibrosarcoma (WEHI-164) was examined by intravenous (IV) and intratumoral (IT) injection and the sizes of the inoculated tumors, IFN-γ production, and CD4+/CD8+ T cell infiltration were determined. The inoculated tumors were also examined histologically. In the mice in the IV-injected group, a significant reduction (P < 0.02) of tumor size was observed in comparison with mice in the IT-injected and control groups. Furthermore, the mice in the IV-injected group showed significantly higher levels of IFN-γ (P < 0.009) and CD4+/CD8+ T cell infiltration when compared with the other groups (P < 0.02). A significantly higher frequency of necrosis in tumor tissues was also observed in mice in the IV-injected group (P < 0.05). Our present findings suggest that tumor cell death is caused by increased cytotoxic T-cell activity and cytokine levels in response to the IV injection of SEB and that SEB may be a good option for use as a novel therapy in patients with fibrosarcoma. An erratum to this article can be found at     

Decreased serum testosterone concentration in male heroin and methadone addicts

The serum concentrations of testosterone, estradiol-17β, FSH and LH were measured in 22 male subjects addicted to heroin or methadone. Serum testosterone concentration was decreased in many of these subjects without consistent abnormalities in the other hormones. It is suggested that decreased sexual function in male addicts may be partially due to a decrease in serum testosterone concentration.     

Response of Pseudomonas tolaasii,the causal agent of mushroom brown blotch disease to the volatile compounds produced by endofungal bacteria

Volatile organic compounds (VOCs) produced by bacteria have significant potential to control phytopathogens. In this study, the VOCs produced by endofungal bacteria Pseudomonas sp. Bi1, Bacillus sp. De3, Pantoea sp. Ma3 and Pseudomonas sp. De1 isolated from wild growing mushrooms were evaluated in vitro for their antagonistic activity against Pseudomonas tolaasii Pt18, the causal agent of mushroom brown blotch disease. The gas chromatography–mass spectrometry (GC–MS) analysis revealed that strains Pseudomonas sp. Bi1, Pseudomonas sp. De1, Bacillus sp. De3 and Pantoea sp. Ma3 produced eight, sixteen, nine, and twelve VOCs, respectively. All antagonistic endofungal bacteria produced VOCs which significantly reduced brown blotch symptoms on mushroom caps and inhibited the growth of P. tolaasii Pt18 at the varying levels. Scanning electron microscopy revealed severe morphological changes in cells of P. tolaasii Pt18 following exposure to the VOCs of Pseudomonas sp. Bi1 and De1. Furthermore, The VOCs produced by endofungal bacteria significantly reduced swarming, swimming, twitching, chemotaxis motility and biofilm formation by P. tolaasii Pt18 cells, which are essential contributors to pathogenicity. This is to first report about the inhibition effects of VOCs produced by antagonistic bacteria on virulence traits of P. tolaasii. Our findings provide new insights regarding the potential of antibacterial VOCs as a safe fumigant to control mushroom brown blotch disease.

     

Molecular-level insights into furfural hydrogenation intermediates over single-atomic Cu catalysts on magnesia and silica nanoclusters

This paper addresses the geometrical, charge, topological, and thermochemical data for the adsorption of the relevant furan species during hydrogenation of furfural to furfuryl alcohol over Cu/SiO₂ and Cu/MgO catalysts. The calculations indicated that the binding of Cu to magnesia was stronger than that on silica. The results also indicated that the formation of an alkoxide intermediate is more favoured than that of a hydroxyalkyl species. The binding energetic data were in general agreement with the geometrical parameters, electron densities, and molecular orbital energy levels. The QTAIM data revealed the closed-shell interactions between Cu and O atoms on both of the catalysts. Finally, the analysis of the partial charges on the atoms revealed that the Cu atom acquires a positive charge upon interaction with the carbonyl group owing to a π-back-donation from Cu to the C?=?O bond.