A variety of approaches have been employed in order to identify novel genetic causes of RCC including the mapping and characterisation of RCC-associated constitutional translocations and genetic association studies. The released IFNs can subsequently activate IFN-stimulated genes, resulting in cellular gene expression profile changes that may contribute to adverse sideeffects such as global degradation of mRNA, inhibition of general protein translation or cell death. Moreover, long-term and high-level shRNA expression can result in oversaturation of the endogenous cellular microRNA pathways leading to cytotoxicity and eventually fatality, as reported previously. The amiRNAs represent a type of shRNAs in which a siRNA sequence is embedded into a native microRNA scaffold, most commonly into that of miR-30 or miR-155. In contrast to shRNAs, amiRs are expressed from polymerase II promoters and are processed consecutively into functionally active siRNAs via the nuclear class 2 RNase III enzyme Drosha and the cytoplasmic endoribonuclease Dicer. Several studies have compared shRNAs and amiRs Tris(2-carboxyethyl)phosphine hydrochloride regarding their efficiency and safety. The general trend of these studies is that amiRs substantially reduce the toxicity observed for the shRNAs of the same constructs. The efficiency of gene silencing mediated by amiRNAs has been reported to be higher, comparable or lower in comparison to shRNAs. We demonstrated the first successful treatment of experimental heart failure by RNAi in vivo. An AAV9 vector and adenoviral vector-mediated cardiac expression of rat PLB-specific shRNA resulted in strong cardiac down-regulation of PLB. This led to restoration of the compromised left ventricular contractile function. It also significantly reduced cardiac dilatation, hypertrophy, cardiomyocyte Anlotinib Dihydrochloride diameter and cardiac fibrosis. Importantly, no adverse side effects were observed using this shPLBr gene therapeutic approach in rats. More recently, however, Bish et al. evaluated the efficiency and safety of an adapted shPLB in healthy dogs. They found that AAV6 vector-mediated cardiac shPLB delivery to these animals resulted in the strong knockdown of PLB, accompanied by severe cardiac toxicity. Here, we show that scAAV6-amiR155-PLBr, which expresses a newly engineered small regulatory RNA directed against the negative SERCA2a modulatory protein PLB, improves the SERCA2a-catalyzed Ca2+ transport activity of the SR in CM. The efficiency of scAAV6-amiR155-PLBr was as high as that of an AAV6 vector expressing the conventional shPLBr that was previously used for PLB silencing. Importantly, our data reveal that scAAV6-amiR155-PLBr exhibits an improved cardiac safety compared to the shPLBr-expressing vector. In a previous study, we demonstrated the therapeutic efficacy of shPLBr in a rat heart failure model using AAV9 vectors for cardiac delivery. No negative side effects were detected in this study. Severe cardiac toxicity, however, was observed in healthy canines after AAV6 vector-mediated delivery of shPLB. Reducing the expression of the shRNA by decreasing the vector dose or the use of weaker promoters are potential ways to prevent shRNAinduced side effects. This procedure, however, is not always successful and shRNAs can remain toxic, even when shRNA levels are reduced. Thus, reduction of shRNA toxicity might come at the price of loss of therapeutic efficiency.
Month: July 2019
Thrombus in a substantial proportion of the STEMI patients and the composition of the these thrombi was often heterogeneous
Showing in part features of fresh, of lytic, and organized thrombus. These results support the concept of coronary artery disease as a dynamic process. Disruption of atherosclerotic plaques may act as a stimulus for repeated or ongoing thrombosis, which ultimately progresses over a period of days or even weeks to thrombotic occlusion with a secondary fresh thrombus. Systematic histopathological analyses of the atherothrombotic material obtained with thrombus aspiration during primary PCI in large patient cohorts are limited. Our findings are in line with our previous results that describe histopathological analyses of aspirated atherothrombotic material in a smaller group of 211 STEMI patients in whom we identified older thrombus in approximately 50% of patients. The insights in the mechanisms of UNC0642 coronary thrombosis mainly come from detailed analyses of underlying plaque morphologies in necropsy specimen from sudden death victims. Autopsy studies on the histopathology of the progression of coronary plaques demonstrated the occurrence of clinically silent coronary nonocclusive atherothrombotic events before the occlusive atherothrombotic event. Furthermore, multiple subclinical episodes of plaque disruption, followed by healing, are an important mechanism of atherosclerotic plaque growth. A close relationship has been demonstrated between the number of previous plaque disruptions and the mean percentages stenosis in the coronary artery. Further, Henriques de Gouveia et al. demonstrated that histopathological evidence of plaque instability for some time was present in the majority of sudden coronary death victims. They concluded that plaque disruption with superimposed thrombus formation starts days or even weeks before the time of death. Subclinical episodes of plaque disruption may have the potential to precondition the myocardium. An alternative explanation is that several subclinical plaque disruptions may results in the development of collateral vessels. Therefore, patients with successive thrombotic occlusion after several subclinical plaque disruptions may experience less acute cardiac symptoms compared with patients in whom plaque disruption immediately leads to a superimposed luminal thrombus with total occlusion. This may explain why patients with lytic or organized thrombus had a significantly longer total ischemic time compared with patients with fresh thrombus. Interestingly, distal embolization was significantly different between patients with fresh, lytic or organized thrombus, with the highest percentage in patients with thrombus with α-santonin lytic changes. Thrombus embolization may be less frequent when the thrombus is fresh and fragile or when the thrombus is organized and more solid and attached to the vessel wall. This pathological finding is compatible with the report by Kondo et al, who found an association between the no-reflow phenomenon and a longer ischemic time. These findings suggest the presence of a time window of several days after plaque disruption when distal embolization of thrombus is most likely to occur in association with mechanical reperfusion. Except for the TAPAS study, previous studies with thrombus aspiration have been neutral or negative. In some patients, thrombus aspiration was not possible depending on coronary anatomy, and in 353 patients no material was obtained.
We demonstrated that this CRAd could replicate very poorly in cells expressing miR-199
While its replication could proceed regularly in cells lacking the expression of this miRNA. Since miR-199 is highly expressed in normal liver, but not in HCC, this virus seems to be well suited for the treatment of liver cancer. By testing various experimental in vivo models, we confirmed this potential opportunity. First, in 3 days old mice, which have a limited or absent Torin 1 immune response, Ad-199T was not able to replicate in the liver while an identical control virus, lacking the miR-199 target sites, could efficiently undergo several rounds of replication. In this model, control adenovirus, but not Ad-199T, induced an evident hepatoxicity, as evidenced by histological and immunohistochemical analyses. This foreseeable finding was a consequence of the inhibitory effect imposed by miR-199 on Ad-199T replication, thereby preventing its lytic activity in healthy cells. This property is shared with other recently developed miRNA dependent oncolytic adenoviruses, like miR-122-based adenovirus detargeting vectors, which exhibited a reduced virus-related liver toxicity. However, miR-122 is a liver-specific miRNA and is not expressed in any other tissue, leaving open the possibility that toxicities due to viral replication could eventually affect other tissues. Since miR-199 is instead expressed at variable but significant level in any normal tissues, Ad-199T could lack toxicity in tissues other than liver as well. To support the anti-tumor oncolytic activity of Ad-199T, we proved that the virus could slow-down the growth of xenografts made of liver cancer cells subcutaneously implanted into nude mice. Also in this model, the reduced viral toxicity was supported by the fact that all treated immune deficient mice could survive following 6 consecutive administrations of large amounts of replication-competent viruses. As found with other oncolytic adenoviruses, Ad-199T did not cause tumor regression, but the anti-tumor effect was significant. As previously mentioned, it is possible that this virus, like other CRAds, could find its best use to boost efficacy of chemo or radiotherapy. We also investigated the anti-tumor effect in an immunecompetent host mouse model, highly susceptible to the development of liver primary tumors. Administration of Ad-199T induced a significant reduction of the number and size of tumor nodules, most likely because Ad-199T could replicate more efficiently in neoplastic than in normal liver cells. A conceptually similar but different oncolytic virus was developed by Jin et al. It was engineered as a let-7 dependent oncolytic adenovirus, able to replicate only in cells lacking the let-7 miRNA. The authors specify that let-7 is down-regulated in about 36% of HCC, thereby suggesting that this virus could Rapamycin produce a potential therapeutic effect in this subset of HCCs. Together with the studies on miR-122 and let-7, the present study indicates that the knowledge of miRNA expression levels in normal and cancer cells may be applied to the design of oncolytic viruses that combine selective efficacy against cancer cells with minimal adverse toxic effects. In nonmuscle-invasive tumors progression to muscle-invasive disease is rare and occurs in 3 to 5% of all cases. While patients with genetically stable nonmuscle invasive low grade tumors show an excellent 5 year survival rate of 96%, patients with deep muscle infiltrating high grade tumors have the worst prognosis with a 5 year survival rate of about 20%. In exophytic, nonmuscle invasive low grade tumors transurethral resection is the local, bladder preserving, therapy of choice. In muscle infiltrating tumors radical cystectomy with extended pelvic lymph node dissection is the generally accepted treatment with curative intent. In patients with severe comorbidities alternative treatment option is the combined chemo- and radiation therapy.
They are introduced by destabilization of current functional patterns and hence by critical dynamic fluctuations
The ventral orbito-striatal network seems to be more active during emotional processes and may be responsible for relaying the emotional OCD components such as fear and anxiety. The dorso-fronto-striatal connections are part of a system which could be responsible for mainly cognitive and executive deficits related to compulsions. Some regions of the parietal cortex, the cerebellum, and the superior temporal cortex are interconnected via the dorsolateral prefrontal cortex, meaning that there is an interface between the fronto-striatal and the fronto-parietal loop. Because of the resulting activity during symptom provocation and its functions related to attention monitoring and reaction inhibition, the parietal cortex may play a role in controlling obsessive thoughts and compulsive impulses. Therapy options for OCD are the administration of selective serotonin reuptake inhibitors and psychotherapy. To this end, both behavior therapy with exposure/response prevention and also cognitive behavior therapy have both proven effective in a number of studies. Several neuroimaging studies have shown the effects of psychotherapy on neuronal activation patterns and brain metabolism. However, the process of dynamic change itself has not yet been the object of investigation. Those few studies that have been performed by repeatedly using functional MRI in the course of psychotherapy have been conducted in dialectic-behavioral therapy applied to borderline personality disorders and in the psychodynamic therapy of chronic depression. A single-case study on patients with OCD revealed first evidence on discontinuous change of symptom severity preceded by increased dynamic complexity of therapyrelated emotions and cognitions, and a pronounced change in neuronal activity during this period. In psychotherapy research there has been a growing interest in the study of patterns of change processes. More frequently, internet-based methods have been used for process monitoring and ambulatory assessment. Meanwhile, converging findings have shown that psychotherapy is a nonlinear process with chaotic dynamics and non-stationarities, i.e., qualitative changes of dynamic patterns, reminiscent of nonequilibrium phase WY 14643 transitions of self-organizing systems. The term “phase transition” originates from physics where it indicates the spontaneous emergence of new qualities or transitions between such qualities in structures or functions of complex systems. Since there are important differences between physical and human systems, we use the term order transition. It indicates the qualitative changes of patterns in mental and behavioral systems, which are due to selforganizing processes. In complex non-equilibrium systems, they usually take place in a discontinuous way. This corresponds entirely with practical experience and empirical results on psychotherapeutic change processes, which do not occur in an incremental and linear but in a discontinuous way. Navitoclax Critical moments, the “kairos”, specific important experiences or insights, or spontaneous changes of symptom severity have been described repeatedly. In psychoanalysis, the Boston Change Process Study Group worked on the role of “kairos” and sudden pattern transitions in the tacit procedural knowledge of interpersonal experiences. Most prominent are findings on early rapid responses in psychotherapy which give rise to the renowned research field on sudden changes in psychotherapy. The study at hand provides evidence of discontinuous transitions in inpatient psychotherapy of OCD patients concerning their subjective experience and the corresponding neuronal activity. Such transitions could be central markers of selforganization processes.
It has to be mentioned that resistance can be also acquired due to active degradation of the peptides
By proteases or due to binding of the peptides to certain cell envelope structures/compounds that decrease effective concentrations. Nevertheless, the difference in prokaryotic and eukaryotic membrane architecture already imparts selectivity of AMPs for microorganisms and reduces toxic side effects against cells of higher organisms. In plants several families of antimicrobial peptides have been identified, such as thionins, defensins, lipid transfer proteins, hevein-and knottin-like proteins and snakins, differing in structure, size and cysteine content. The role of antimicrobial peptides in defense is well established and their use in agriculture was already proposed when they were first discovered. Especially antimicrobial peptides from animals were analysed for their plant protecting potential. Magainin, cecropin and modified or chimeric forms of these two peptides were mainly used in in-vitro or ex-vivo studies against plant pathogens. However, since the cationic and hydrophobic characteristics of the antimicrobial peptides determine their mode of action, direct modification of these features allows the rational design of new AMPs. Here, we present the design of a novel set of antimicrobial peptides harbouring different structural and chemical properties, and depict their possible use in plant protection. Several of our designed peptides were highly toxic for a wide range of bacterial and fungal plant pathogens, e.g. Pseudomonas corrugata, Xanthomonas vesicatoria, and Cladosporium herbarum at CUDC-907 distributor concentrations below 1 mg/ ml, whereas no toxic effects against human cells or plant protoplasts were observed at these concentrations. Altogether, more than 60 peptides were designed and analyzed for their potential use as plant protecting agents in in-vitro inhibition assays. Furthermore, spraying the designed peptides on the surface of infected leaves demonstrated their antimicrobial activity directly on plants and displays a way of practical application. Leucine, isoleucine, valine, phenylalanine, alanine, methionine, glycine, serine, and threonine residues were used to generate hydrophobic regions. A helical structure of the peptides was ensured by inserting strong helix-forming amino acids, such as leucine and alanine. We selected a derivative of the scorpionderived antimicrobial peptide IsCT and the frog-derived peptide magainin II as templates. The mutation tool of the SWISS-Pdbviewer software was used to modify the template molecules and to design new peptides. The software enables to see directly a structural model of the designed peptides. To investigate, whether a distinct structural pattern is particular important for antimicrobial activity, four leading structures were designed, each containing four peptides differing in charge, hydrophobicity, location and size of the hydrophobic and charged clusters. A detailed description of the designing strategy can be found in the supplement. The amino acid sequences were analysed against an AMP database to ensure that they are differ from sequences of already known AMPs. Hydrophobicity was calculated based on the hydrophobicity scale for amino acids and pI values were calculated using the AZ 960 ExPASy ProtParam tool. The helical structure was predicted using NNPREDICT program for protein secondary structure prediction. Peptides of group I consist of a dominant charged cluster and a small hydrophobic region. Group II contains peptides with a dominant hydrophobic cluster and a small charged region. In all peptides of group III the hydrophobic and the charged regions have the same size and are separated lengthwise of the molecule. In peptides of group IV the charged regions are located at the N- and C-termini, which are separated by a central hydrophobic cluster. In peptides SP13 and SP16 the charged Nterminal and C-terminal parts are connected by a charged bar.