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41.
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.  相似文献   
42.
Qiao  Wanli  Akhter  Nasrin  Fang  Xiaowen  Maximova  Tatiana  Plaku  Erion  Shehu  Amarda 《BMC genomics》2018,19(7):671-13

Background

The protein energy landscape underscores the inherent nature of proteins as dynamic molecules interconverting between structures with varying energies. Reconstructing a protein’s energy landscape holds the key to characterizing a protein’s equilibrium conformational dynamics and its relationship to function. Many pathogenic mutations in protein sequences alter the equilibrium dynamics that regulates molecular interactions and thus protein function. In principle, reconstructing energy landscapes of a protein’s healthy and diseased variants is a central step to understanding how mutations impact dynamics, biological mechanisms, and function.

Results

Recent computational advances are yielding detailed, sample-based representations of protein energy landscapes. In this paper, we propose and describe two novel methods that leverage computed, sample-based representations of landscapes to reconstruct them and extract from them informative local structures that reveal the underlying organization of an energy landscape. Such structures constitute landscape features that, as we demonstrate here, can be utilized to detect alterations of landscapes upon mutation.

Conclusions

The proposed methods detect altered protein energy landscape features in response to sequence mutations. By doing so, the methods allow formulating hypotheses on the impact of mutations on specific biological activities of a protein. This work demonstrates that the availability of energy landscapes of healthy and diseased variants of a protein opens up new avenues to harness the quantitative information embedded in landscapes to summarize mechanisms via which mutations alter protein dynamics to percolate to dysfunction.
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43.

Background aims

Adipose tissue–derived mesenchymal stromal cells (AT-MSCs), widely known as multipotent progenitors, release several cytokines that support cell survival and repair. There are in vitro and in vivo studies reporting the regenerative role of AT-MSCs possibly mediated by their protective effects on functional islet cells as well as their capacity to differentiate into insulin-producing cells (IPCs).

Methods

On such a basis, our goal in the present study was to use three different models including direct and indirect co-cultures and islet-derived conditioned medium (CM) to differentiate AT-MSCs into IPCs and to illuminate the molecular mechanisms of the beneficial impact of AT-MSCs on pancreatic islet functionality. Furthermore, we combined in vitro co-culture of islets and AT-MSCs with in vivo assessment of islet graft function to assess whether co-transplantation of islets with AT-MSCs can reduce marginal mass required for successful islet transplantation and prolong graft function in a diabetic rat model.

Results

Our findings demonstrated that AT-MSCs are suitable for creating a microenvironment favorable for the repair and longevity of the pancreas β cells through the improvement of islet survival and maintenance of cell morphology and insulin secretion due to their potent properties in differentiation. Most importantly, hybrid transplantation of islets with AT-MSCs significantly promoted survival, engraftment and insulin-producing function of the graft and reduced the islet mass required for reversal of diabetes.

Conclusions

This strategy might be of therapeutic potential solving the problem of donor islet material loss that currently limits the application of allogeneic islet transplantation as a more widespread therapy for type 1 diabetes.  相似文献   
44.
L-Arginine (L-Arg) affects variousparameters that modulate the progression of renal disease. These samefactors [e.g., glomerular filtration rate, changes in mesangialcell (MC) tension, and production of NO] are all controlled atleast in part by changes in MC intracellular Ca2+concentration([Ca2+]i). Wetherefore evaluated the effect of L-Arg on MC[Ca2+]i. We found thatL-Arg inhibits the vasopressin-stimulated rise in MC[Ca2+]i both in rat andmurine cell cultures. This effect does not appear to be due tometabolism of L-Arg to either NO or L-ornithine (L-Orn). Blocking the metabolism of L-Arg withN-monomethyl-L-arginine, an NOsynthase inhibitor, or with 20 mM L-valine(L-Val), an inhibitor of Orn formation,does not reverse the inhibition. However, other cationic amino acids,as well guanidine, the functional group ofL-Arg, all inhibit thevasopressin-stimulated rise in[Ca2+]i,consistent with a structural basis for this effect. We conclude that1)L-Arg inhibitsvasopressin-stimulated murine and rat MC [Ca2+]irise, 2) this inhibition is notmediated by metabolism of L-Arg to either NO or L-Orn, and3) the effect ofL-Arg is due to its cationicfunctional group, guanidine.

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45.
How to effectively delivering therapeutic agents, including γ-secretase inhibitors (GSIs), into live cells, remains a significant challenge. This study assessed the effect of Notch signaling inhibition by examining levels of the Notch1 intracellular domain (N1ICD) in cultured oral cancer cells analyzed with random stitched images (2D) and 3D visualizations using confocal microscopy and quantitative gene analysis. Substantially, we have developed a novel method to assist the delivery of γ-secretase inhibitor, DAPT, into live cells in the presence of an effective minimum concentration of Triton-X100 (0.001%) without damaging cell activity and membrane integrity assessed with cell proliferation assays. The images obtained in this study showed that DAPT alone could not block the γ-secretase inhibitor despite inhibiting cell growth. Further analysis of quantitative gene expressions of Notch signaling canonical pathway to verify the effectiveness of the novel method for delivering inhibitor into live cells, displayed deregulation of Notch1, Delta-like ligand 1 (DLL1) and hairy and enhancer of split 1 (Hes1). Our data suggest that Notch1/Hes1 signaling pathway is deactivated using DAPT with a low dose of Triton-X100 in this cancer cells. And the finding also suggests that Notch1 could be engaged by DLL1 to promote differentiation in oral cancer cells. Using this approach, we demonstrate that Triton-X100 is a promising and effective permeabilization agent to deliver γ-secretase inhibitor DAPT into live oral epithelial cells. This strategy has the potential to implicate in the treatment of cancer diseases.  相似文献   
46.
The demand for cloud computing is increasing dramatically due to the high computational requirements of business, social, web and scientific applications. Nowadays, applications and services are hosted on the cloud in order to reduce the costs of hardware, software and maintenance. To satisfy this high demand, the number of large-scale data centers has increased, which consumes a high volume of electrical power, has a negative impact on the environment, and comes with high operational costs. In this paper, we discuss many ongoing or implemented energy aware resource allocation techniques for cloud environments. We also present a comprehensive review on the different energy aware resource allocation and selection algorithms for virtual machines in the cloud. Finally, we come up with further research issues and challenges for future cloud environments.  相似文献   
47.
Background:Vascular endothelial growth factor (VEGF) is one of the primary angiogenesis regulators in solid cancers. Brain solid tumors are life-threatening diseases in which angiogenesis is an important phase of tumor development and progression. In the present study, VEGF-A and VEGF receptor (VEGF-R1) gene expression was evaluated in CNS brain tumors.Methods:VEGF-A and VEGF-R1 expression was quantified using real-time PCR on fresh biopsies of 38 supratentorial brain tumors compared to 30 non-tumoral tissues. Then, the correlations were investigated with clinic-pathological and demographic factors of the patients.Results:PCR product sequencing confirmed the validity of qRT-PCR. Although VEGF-A and VEGF-R1 expression showed increasing trends with the progression of cell proliferation in different stages of astrocytoma, VEGF-R1 did not meet the 95% confidence interval in other brain tumors. An increasing trend in VEGF-A expression and a declining trend in VEGF-R1 expression from Stage I to II were observed in meningioma. VEGF-A and VEGF-R1 expression had no significant correlation with age and gender. Although peritumoral brain edema (PTBE) in astrocytoma was significantly associated with tumor stages, VEGF-A and VEGF-R1 were not correlated with PTBE in meningioma and metastasis.Conclusion:VEGF-A is a valuable factor for the prognosis of PTBE and malignancy in astrocytoma and is helpful in monitoring treatment approaches.Key Words: Angiogenesis, Brain edema, Brain neoplasm, Peritumoral brain, VEGF, VEGFR1  相似文献   
48.
Glucocorticoids (GCs) initiate oxidative stress and cause renal damage which lead to hypertension, heart failure and ultimately death. The current study aimed to investigate the alterations in serum biochemical parameters i.e. HDL and LDL; gross anatomy, histomorphology and histomorphometry of broiler kidney in response to dietary GC, dexamethasone (DEX). Day old chicks (DOCs) were randomly assigned into four groups: control and three treatment groups (T1, T2 and T3). The control group was fed commercial broiler type ration and the treated groups were fed commercial broiler type ration containing GC (Dexamethasone @ 3, 5 and 7 mg/kg in T1, T2 and T3 group respectively). To measure the biochemical parameters, blood samples were collected on days 7, 14, 21, and 28 of the experiment. For histological investigation, kidney (left) samples were collected from the individual birds after sacrificing on days 7, 14, 21, and 28 of the experiment. Histomorphological alterations of the kidney were assessed by routine hematoxylin and eosin (H&E) staining. Biochemical analysis showed significantly increased serum HDL and LDL level compared to the control. In gross study, dark congested kidney was found with significantly decreased weight, length and width. Treatment with DEX augmented congestion, inflammation and fibrosis in kidney, as evidence by histomorphometric study. Extensively degenerated and atrophied glomeruli, degenerated tubular epithelium with distorted tubules and inter tubular empty spaces were seen. Percentage of atrophied glomeruli increased significantly and maximum percentage of glomerular atrophy was seen at day 28. These changes were found more explicitly in the higher dose group. Histomorphometric study also revealed significant decrease in the diameter of glomerulus. The findings of this study suggest that DEX may alter the serum biochemical parameters as well as kidney gross and histomorphology.  相似文献   
49.
The Common Pheasant Phasianus colchicus is widely distributed in temperate to subtropical regions of the Palaearctic realm. Populations of Common Pheasant have been classified into five subspecies groups based on morphological variations in male plumage. Previous phylogeographical studies have focused on limited sets of subspecies groups in the eastern Palaearctic and knowledge on subspecies in the western Palaearctic region is still poor. In this study, we undertake the first comprehensive analysis of subspecies from all five defined subspecies groups across the entire Palaearctic region. Two mitochondrial (CYTB and CR) and two nuclear (HMG and SPI) loci were used to investigate genetic relationships of these subspecies groups and to infer their dispersal routes. Our results revealed that the subspecies elegans, with its range in northwestern Yunnan, China, was in the basal position among 17 studied subspecies, supporting a previous hypothesis that the Common Pheasant most probably originated in forests in southeastern China. Subspecies in the western Palaearctic region nested within the most subspecies‐rich torquatus group (‘Grey‐rumped Pheasants’), indicating that the torquatus group is not a clade but instead forms a gradation with other subspecies and subspecies groups. Our dating analysis suggested that the initial divergence among populations of Common Pheasant originated around 3.4 Mya with subsequent dispersal into the Western Palaearctic region during the Late Pliocene–Lower Pleistocene approximately 2.5–1.8 Mya. We propose two possible east‐to‐west colonization routes for the Common Pheasant and suggest conservation implications for some regional subspecies. Overall, this study demonstrates the lack of concordance between morphology‐based subspecies delimitation and their genetic relationships. This is likely to be a consequence of initial isolation due to historical vicariance followed by population admixture due to recent range expansion of Common Pheasant in the western Palaearctic region.  相似文献   
50.
Giardia lamblia causes malabsorption. The aim of this study was to evaluate serum and saliva calcium and magnesium levels in patients with giardiasis. Thirty patients with giardiasis as a case and 30 person without giardiasis as a control group were enrolled. The stimulated and unstimulated whole saliva and serum calcium and magnesium levels were assayed by Arsenazo reaction and xylidyl blue complex methods, respectively. Mean calcium and magnesium level was low in serum and stimulated saliva of case group than that of controls. However, they were higher in the unstimulated saliva of the case group. It is suggested that patients suffering from giardiasis have low calcium and magnesium levels, and they lose the most of calcium and magnesium by saliva during unstimulated condition.  相似文献   
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