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1.
Lung diseases are a major cause of global morbidity and mortality that are treated with limited efficacy. Recently stem cell therapies have been shown to effectively treat animal models of lung disease. However, there are limitations to the translation of these cell therapies to clinical disease. Studies have shown that delayed treatment of animal models does not improve outcomes and that the models do not reflect the repeated injury that is present in most lung diseases. We tested the efficacy of amnion mesenchymal stem cells (AM-MSC), bone marrow MSC (BM-MSC) and human amniotic epithelial cells (hAEC) in C57BL/6 mice using a repeat dose bleomycin-induced model of lung injury that better reflects the repeat injury seen in lung diseases. The dual bleomycin dose led to significantly higher levels of inflammation and fibrosis in the mouse lung compared to a single bleomycin dose. Intravenously infused stem cells were present in the lung in similar numbers at days 7 and 21 post cell injection. In addition, stem cell injection resulted in a significant decrease in inflammatory cell infiltrate and a reduction in IL-1 (AM-MSC), IL-6 (AM-MSC, BM-MSC, hAEC) and TNF-α (AM-MSC). The only trophic factor tested that increased following stem cell injection was IL-1RA (AM-MSC). IL-1RA levels may be modulated by GM-CSF produced by AM-MSC. Furthermore, only AM-MSC reduced collagen deposition and increased MMP-9 activity in the lung although there was a reduction of the pro-fibrogenic cytokine TGF-β following BM-MSC, AM-MSC and hAEC treatment. Therefore, AM-MSC may be more effective in reducing injury following delayed injection in the setting of repeated lung injury.  相似文献   
2.
Cardioprotection by Mg Sulfate (MgSO4) during ischemia/reperfusion (I/R) is attributed largely to the Mg2+ cation. However, Mg-gluconate (MgGl2) may provide added benefit, possibly through its anion's antioxidant properties. Protective effects of both Mg-salts and their anions during 30 min global I and 50 min R were assessed in Langendorff-perfused (Krebs-Henseleit buffer) rat hearts. Recovery of function was compared between untreated hearts and those receiving supplement (2.4 mM MgGl2, MgSO4, or Na2SO4, or 4.8 mM NaGI) for 5 min prior to I and during the initial 30 min R. The final 20 min R was conducted without supplement. End diastolic pressure (EDP, mmHg) of the 50 min reperfused MgGl2 group (2.6) was lower than MgSO4 (16.2) and untreated (35.6) groups, and the NaGI group (25.2) was considerably lower than Na2SO4 (38.8). Recovery of developed pressure (% preischemic DP) at the onset of R for MgGl2 (74.9) was greater than MgSO4 (37.9) and untreated (33.2). After 50 min, MgGl2 (77.9) and MgSO4 (66.9) provided protection compared to untreated (51.8). In separate studies, ESR spin trapping with alpha-phenyl-N-tert-butylnitrone (3 mM PBN) showed that I/R alkoxyl radical production was reduced with MgGl2 (0.0 vs. 2.4 vs. 3.6 mM: 184 vs. 97 vs. 54.8 nM/g tissue x min) to a greater extent than seen with MgSO4 (3.6 mM: 108). Additional studies suggest that Gl(1-), unlike SO4(2-), may scavenge hydroxyl radicals, accounting for the added protection. MgGl2 treated hearts exhibited less postischemic dysfunction and oxidative injury compared to MgSO4, suggesting the contribution of Gl(1-) to cardioprotection.  相似文献   
3.
Enzymes from psychrophiles catalyze the reactions at low temperatures with higher specific activity. Among all the psychrophilic enzymes produced, cold active β-galactosidase from marine psychrophiles revalorizes a new arena in numerous areas at industrial level. The hydrolysis of lactose in to glucose and galactose by cold active β-galactosidase offers a new promising approach in removal of lactose from milk to overcome the problem of lactose intolerance. Herein we propose, a 3D structure of cold active β-galactosidase enzyme sourced from Pseudoalteromonas haloplanktis by using Modeler 9v8 and best model was developed having 88% of favourable region in ramachandran plot. Modelling was followed by docking studies with the help of Auto dock 4.0 against the three substrates lactose, ONPG and PNPG. In addition, comparative docking studies were also performed for the 3D model of psychrophilic β-galactosidase with mesophilic and thermophilic enzymes. Docking studies revealed that binding affinity of enzyme towards the three different substrates is more for psychrophilic enzyme when compared with mesophilic and thermophilic enzymes. It indicates that the enzyme has high specific activity at low temperature when compared with mesophilic and thermophilic enzymes.  相似文献   
4.
Melanoma is the most lethal cutaneous cancer with a highly aggressive and metastatic phenotype. While recent genetic and epigenetic studies have shed new insights into the mechanism of melanoma development, the involvement of regulatory non‐coding RNAs remain unclear. Long non‐coding RNAs (lncRNAs) are a group of endogenous non‐protein‐coding RNAs with the capacity to regulate gene expression at multiple levels. Recent evidences have shown that lncRNAs can regulate many cellular processes, such as cell proliferation, differentiation, migration and invasion. In the melanoma, deregulation of a number of lncRNAs, such as HOTAIR, MALAT1, BANCR, ANRIL, SPRY‐IT1 and SAMMSON, have been reported. Our review summarizes the functional role of lncRNAs in melanoma and their potential clinical application for diagnosis, prognostication and treatment.  相似文献   
5.
Yee  KK; Costanzo  RM 《Chemical senses》1998,23(5):513-519
Following recovery from olfactory nerve transection, animals regain their ability to discriminate between odors. Odor discrimination is restored after new neurons establish connections with the olfactory bulb. However, it is not known if the new connections alter odor quality perception. To address this question, 20 adult hamsters were first trained to discriminate between cinnamon and strawberry odors. After reaching criterion (> or = 90% correct response), half of the animals received a bilateral nerve transection (BTX) and half a surgical sham procedure. Animals were not tested again until day 40, a point in recovery when connections are re-established with the bulb. When BTX animals were tested without food reinforcement, they could not perform the odor discrimination task. Sham animals, however, could discriminate, demonstrating that the behavioral response had not been extinguished during the 40 day period. When reinforcement was resumed, BTX animals were able to discriminate between cinnamon and strawberry after four test sessions. In addition, their ability to discriminate between these two familiar odors was no different than that of BTX and sham animals tested with two novel odors, baby powder and coffee. These findings suggest that, after recovery from nerve transection, there are alterations in sensory perception and that restoration of odor quality discrimination requires that the animal must again learn to associate individual odor sensations with a behavioral response.   相似文献   
6.
7.
Prevention by glycine of protein crosslinking which accompanies binding of levuglandin E2 (LGE2) is shown to involve binding of glycine with the protein-LGE2 adduct. With ovalbumin, the LGE2 adduct initially binds nearly 2 equivalents of glycine, but the capacity to bind glycine decreases with time reflecting a competition, inter alia, with crosslinking.  相似文献   
8.

Background

Highly sensitive and specific urine-based tests to detect either primary or recurrent bladder cancer have proved elusive to date. Our ever increasing knowledge of the genomic aberrations in bladder cancer should enable the development of such tests based on urinary DNA.

Methods

DNA was extracted from urine cell pellets and PCR used to amplify the regions of the TERT promoter and coding regions of FGFR3, PIK3CA, TP53, HRAS, KDM6A and RXRA which are frequently mutated in bladder cancer. The PCR products were barcoded, pooled and paired-end 2 x 250 bp sequencing performed on an Illumina MiSeq. Urinary DNA was analysed from 20 non-cancer controls, 120 primary bladder cancer patients (41 pTa, 40 pT1, 39 pT2+) and 91 bladder cancer patients post-TURBT (89 cancer-free).

Results

Despite the small quantities of DNA extracted from some urine cell pellets, 96% of the samples yielded mean read depths >500. Analysing only previously reported point mutations, TERT mutations were found in 55% of patients with bladder cancer (independent of stage), FGFR3 mutations in 30% of patients with bladder cancer, PIK3CA in 14% and TP53 mutations in 12% of patients with bladder cancer. Overall, these previously reported bladder cancer mutations were detected in 86 out of 122 bladder cancer patients (70% sensitivity) and in only 3 out of 109 patients with no detectable bladder cancer (97% specificity).

Conclusion

This simple, cost-effective approach could be used for the non-invasive surveillance of patients with non-muscle-invasive bladder cancers harbouring these mutations. The method has a low DNA input requirement and can detect low levels of mutant DNA in a large excess of normal DNA. These genes represent a minimal biomarker panel to which extra markers could be added to develop a highly sensitive diagnostic test for bladder cancer.  相似文献   
9.
Levuglandin E2 (LGE2) is a γ-keto aldehyde produced by rearrangement of the prostaglandin endoperoxide PGH2 under the aqueous conditions of its biosynthesis. We show that exogenous LGE2 enters cells and efficiently inhibits the first synchronous cell division of fertilized sea urchin eggs. We attribute this inhibition to covalent modification of tubulin and thereby to inhibition of microtubule assembly.  相似文献   
10.
Rat C6 glioma cultures were exposed to labelled sodium phosphate after treatment with NE with or without propanolol. Histones and non-histone proteins (NHP) were extracted from chromatin and there was no significant change in the specific activity of the total pool of histones and NHP between control and other two groups. However, after electrophoretic separation F2a2 histone showed a 60% increase while F2b and F3 histones exhibited a 40% decrease in phosphorylation in response to NE. There was no significant change in the gel pattern of NHP from different groups on SDS-PAGE. However, the 30k dalton NHP showed an increase in phosphorylation in response to NE and this increment was blocked by propanolol. The possible role of β-receptors on nuclear protein phosphorylation and genomic expression is discussed.  相似文献   
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