Chromatography is undoubtedly the workhorse of downstream processes, affording high resolution for bioseparations. At the same time, it has the notoriety of being the single largest cost center in ...downstream processing and of being a low-throughput operation. Consequently, ‘chromatography alternatives’ are an attractive proposition, even if only a reduction in the extent of use of packed beds can be realized. This paper reviews the current state of unit operations posing as chromatography alternatives — including membrane filtration, aqueous two-phase extraction, three-phase partitioning, precipitation, crystallization, monoliths and membrane chromatography — and their potential to do the unthinkable.
There is large literature describing in vitro experiments on heat shock protein (hsp)B1 but understanding of its function in vivo is limited to studies in mice overexpressing human hspB1 protein. ...Experiments in cells have shown that hspB1 has chaperone activity, a cytoprotective role, regulates inflammatory gene expression, and drives cell proliferation. To investigate the function of the protein in vivo we generated hspB1-deficient mice. HspB1-deficient fibroblasts display increased expression of the pro-inflammatory cytokine, interleukin-6, compared to wild-type cells, but reduced proliferation. HspB1-deficient fibroblasts exhibit reduced entry into S phase and increased expression of cyclin-dependent kinase inhibitors p27(kip1) and p21(waf1). The expression of hspB1 protein and mRNA is also controlled by the cell cycle. To investigate the physiological function of hspB1 in regulating inflammation and cell proliferation we used an excisional cutaneous wound healing model. There was a significant impairment in the rate of healing of wounds in hspB1-deficient mice, characterised by reduced re-epithelialisation and collagen deposition but also increased inflammation. HspB1 deficiency augments neutrophil infiltration in wounds, driven by increased chemokine (C-X-C motif) ligand 1 expression. This appears to be a general mechanism as similar results were obtained in the air-pouch and peritonitis models of acute inflammation.
Background Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating problem. Overall, the mortality rate associated with aSAH is 32% to 67%, which makes it the most lethal type of hemorrhagic ...stroke. Once the aneurysm has been treated, cerebral vasospasm is the leading cause of morbidity and mortality associated with aSAH. Thus, ability to effectively prevent or treat cerebral vasospasm could result in significantly improved survival and quality of life for aSAH patients. Unfortunately, partly because of poor understanding of the mechanisms of vasospasm, current diagnosis and treatment can be inconsistent and/or ineffective. Current treatment methods include primarily medical therapy and endovascular methods. Alone, or in combination, these measures can be of benefit in some patients. However, they are not uniformly efficacious and, on an individual basis, they can present significant risks. These risks include stroke, cardiovascular compromise, and death. More effective diagnosis and treatment strategies could significantly improve patient outcomes after aSAH. Unfortunately, clinically reliable biomarker for cerebral vasospasm has yet to be identified. Biomarker discovery may facilitate earlier diagnosis of vasospasm and improved monitoring of the response to treatment. It may help in stratifying patients into categories of risk to develop vasospasm, which could subsequently guide therapy. Indeed, biomarker research may suggest “vasospasm phenotypes” that can be used to guide the most effective type of therapy for that particular patient. The purpose of this manuscript is to review the current cerebral vasospasm biomarker literature. Methods An extensive PubMed literature search was performed. We identified over 100 English language articles with key words cerebral vasospasm and biomarkers. Some of these articles and related references were used as the basis of this review. We focused on related human studies performed within the past 10 years. Results In this review, we focus on recent work identifying molecular markers of cerebral vasospasm following aSAH and the current understanding of the utility of these markers. We highlight novel approaches such as the use of cellular microparticles for the evaluation of cerebral vasospasm. Conclusions Although multiple molecules have been proposed, no single molecule has been shown to be a clinically reliable biomarker for cerebral vasospasm. This is not surprising based on the complex pathogenesis of cerebral vasospasm. Indeed, it is unlikely that a single biomarker will be clinically effective and reliable for predicting cerebral vasospasm. Instead, cerebral vasospasm may be best predicted by a panel of markers and the temporal progression of their relative levels after aSAH. Many such candidate molecules are reviewed herein and can be categorized as markers of cell damage, inflammation, changes in metabolism and vascular tone as well as microparticle-derived biomarkers. Among these, microparticle-derived biomarkers seem to be promising and lend themselves to further study. Biomarker discovery may facilitate earlier diagnosis of vasospasm and improved monitoring of the response to treatment. Ultimately, it may guide in the development of safer and more effective therapies for the most dreaded of aSAH complications.
Adolescent binge alcohol abuse induces long-term changes in gene expression, which impacts the physiological stress response and memory formation, two functions mediated in part by the ventral (VH) ...and dorsal (DH) hippocampus. microRNAs (miRs) are small RNAs that play an important role in gene regulation and are potential mediators of long-term changes in gene expression. Two genes important for regulating hippocampal functions include brain-derived neurotrophic factor (BDNF) and sirtuin-1 (SIRT1), which we identified as putative gene targets of miR-10a-5p, miR-26a, miR-103, miR-495. The purpose of this study was to quantify miR-10a-5p, miR-26a, miR-103, miR-495 expression levels in the dorsal and ventral hippocampus of male Wistar rats during normal pubertal development and then assess the effects of repeated binge-EtOH exposure. In addition, we measured the effects of binge EtOH-exposure on hippocampal Drosha and Dicer mRNA levels, as well as the putative miR target genes, BDNF and SIRT1. Overall, mid/peri-pubertal binge EtOH exposure altered the normal expression patterns of all miRs tested in an age- and brain region-dependent manner and this effect persisted for up to 30 days post-EtOH exposure. Moreover, our data revealed that mid/peri-pubertal binge EtOH exposure significantly affected miR biosynthetic processing enzymes, Drosha and Dicer. Finally, EtOH-induced significant changes in the expression of a subset of miRs, which correlated with changes in the expression of their predicted target genes. Taken together, these data demonstrate that EtOH exposure during pubertal development has long-term effects on miRNA expression in the rat hippocampus.
Adolescent binge alcohol exposure has long-lasting effects on the expression of hypothalamic genes that regulate the stress response, even in the absence of subsequent adult alcohol exposure. This ...suggests that alcohol can induce permanent gene expression changes, potentially through epigenetic modifications to specific genes. Epigenetic modifications can be transmitted to future generations therefore, and in these studies we investigated the effects of adolescent binge alcohol exposure on hypothalamic gene expression patterns in the F1 generation offspring. It has been well documented that maternal alcohol exposure during fetal development can have devastating neurological consequences. However, less is known about the consequences of maternal and/or paternal alcohol exposure outside of the gestational time frame. Here, we exposed adolescent male and female rats to a repeated binge EtOH exposure paradigm and then mated them in adulthood. Hypothalamic samples were taken from the offspring of these animals at postnatal day (PND) 7 and subjected to a genome-wide microarray analysis followed by qRT-PCR for selected genes. Importantly, the parents were not intoxicated at the time of mating and were not exposed to EtOH at any time during gestation therefore the offspring were never directly exposed to EtOH. Our results showed that the offspring of alcohol-exposed parents had significant differences compared to offspring from alcohol-naïve parents. Specifically, major differences were observed in the expression of genes that mediate neurogenesis and synaptic plasticity during neurodevelopment, genes important for directing chromatin remodeling, posttranslational modifications or transcription regulation, as well as genes involved in regulation of obesity and reproductive function. These data demonstrate that repeated binge alcohol exposure during pubertal development can potentially have detrimental effects on future offspring even in the absence of direct fetal alcohol exposure.
EtOH exposure in male rats increases corticotropin-releasing hormone (CRH) mRNA in the paraventricular nucleus of the hypothalamus (PVN), a brain region responsible for coordinating stress and ...anxiety responses. In this study we identified the molecular mechanisms involved in mediating these effects by examining the direct effects of EtOH on CRH promoter activity in a neuronal cell line derived from the PVN (IVB). In addition, we investigated the potential interactions of EtOH and glucocorticoids on the CRH promoter by concomitantly treating cells with EtOH and the glucocorticoid receptor (GR) antagonist RU486, and by sequentially deleting GR binding sites within glucocorticoid response element (GRE) on the CRH promoter. Cells were transiently transfected with a firefly luciferase reporter construct containing 2.5 kb of the rat wild type (WT) or mutated CRH promoter. Our results showed that EtOH treatment induced a biphasic response in CRH promoter activity. EtOH exposure for 0.5 h significantly decreased promoter activity compared to vehicle treated controls, whereas promoter activity was significantly increased after 2.0 h of EtOH exposure. Treatment with RU486, or deletion of the GR binding sites 1 and 2 within the GRE, abolished the EtOH-induced increase in the promoter activity, however did not affect EtOH-induced decrease in CRH promoter activity at an earlier time point. Overall, our data suggest that alcohol exposure directly regulates CRH promoter activity by interfering with the normal feedback mechanisms of glucocorticoids mediated by GR signaling at the GRE site of the CRH promoter.
Vaccinations to prevent infectious diseases are given to target the body’s innate and adaptive immune systems. In most cases, the potency of a live virus vaccine (LVV) is the most critical ...measurement of efficacy, though in some cases the quantity of surface antigen on the virus is an equally critical quality attribute. Existing methods to measure the potency of viruses include plaque and TCID50 assays, both of which have very long lead times and cannot provide real time information on the quality of the vaccine during large-scale manufacturing. Here, we report the evaluation of LumaCyte’s Radiance Laser Force Cytology platform as a new way to measure the potency of LVVs in upstream biomanufacturing process in real time and compare this to traditional TCID50 potency. We also assess this new platform as a way to detect adventitious agents, which is a regulatory expectation for the release of commercial vaccines. In both applications, we report the ability to obtain expedited and relevant potency information with strong correlation to release potency methods. Together, our data propose the application of Laser Force Cytology as a valuable process analytical technology (PAT) for the timely measurement of critical quality attributes of LVVs.
Adventitious agent testing in biomanufacturing requires assays of broad detection capability to screen for as many infectious agents as possible. The current gold standard for general infectious ...adventitious virus screening is the in vitro assay in which test articles are cultured onto a panel of different cell lines and observed for cytopathic effect (CPE). However, this assay is inherently subjective due to the nature of visual observation of cell morphology and labor and time intensive, requiring highly trained personnel to identify CPE. Laser force cytology (LFC) is an alternative, automated analytical method that uses a combination of optical and fluidic forces along with imaging to objectively and quantitatively assess CPE in cell culture. Importantly, because LFC uses no labels or antibodies, the assay is appropriate for general adventitious agent testing. Using LFC, changes in cellular features associated with virally infected cells were identified using principal component analysis. Using these features of infected cells, the sensitivity and earliness of detection with LFC was directly compared with the in vitro assay for a diverse panel of viruses incubated with chinese hamster ovary (CHO), Vero, and Medical Research Council cell strain 5 (MRC‐5) cells. LFC detected viral infection with a sensitivity equal to the in vitro assay on average, but in certain virus and cell combinations including mouse minute virus (MMV) and reovirus 3 in CHO cells, detection was 4 days earlier and for MMV, the limit of detection was 10‐fold lower. Overall, these results demonstrate the ability of LFC to serve as a biopharmaceutical adventitious agent testing methodology with sensitivity equivalent to the in vitro assay, but in an objective and automated manner.
Quantitative analysis of viral infection using laser force cytology (LFC) identified cell properties that detected infected cells for adventitious agent detection within biopharmaceutical processes. The authors used principal component analysis (PCA) on LFC measurements to identify a fundamental set of cell properties to detect infected cells of several different adventitious viruses. Comparing to the current and subjective in vitro assay, equal sensitivity was observed using LFC but in an objective and automated manner.
Alcohol consumption during adolescence has long-term sexually dimorphic effects on anxiety behavior and mood disorders. We have previously shown that repeated binge-pattern alcohol exposure increased ...the expression of two critical central regulators of stress and anxiety, corticotrophin-releasing hormone (CRH) and arginine vasopressin (AVP), in adolescent male rats. By contrast, there was no effect of alcohol on these same genes in adolescent females. Therefore, we tested the hypothesis that 17β-estradiol (E(2)), the predominant sex steroid hormone in females, prevents alcohol-induced changes in CRH and AVP gene expression in the paraventricular nucleus (PVN) of the hypothalamus. To test this hypothesis, postnatal day (PND) 26 females were ovariectomized and given E(2) replacement or cholesterol as a control. Next, they were given an alcohol exposure paradigm of 1) saline alone, 2) acute (single dose) or 3) a repeated binge-pattern. Our results showed that acute and repeated binge-pattern alcohol treatment increased plasma ACTH and CORT levels in both E(2)- and Ch-treated groups, however habituation to repeated binge-pattern alcohol exposure was evident only in E(2)-treated animals. Further, repeated binge-pattern alcohol exposure significantly decreased CRH and AVP mRNA in Ch-, but not E(2)-treated animals, which was consistent with our previous observations in gonad intact females. We further tested the effects of E(2) and alcohol treatment on the activity of the wild type CRH promoter in a PVN-derived neuronal cell line. Alcohol increased CRH promoter activity in these cells and concomitant treatment with E(2) completely abolished the effect. Together our data suggest that E(2) regulates the reactivity of the HPA axis to a repeated stressor through modulation of the habituation response and further serves to maintain normal steady state mRNA levels of CRH and AVP in the PVN in response to a repeated alcohol stressor.
At large values of x , the parton distribution functions (PDFs) of the proton are poorly constrained and there are considerable variations between different global fits. Data at such high x have ...already been published by the ZEUS Collaboration, but not yet used in PDF extractions. A technique for comparing predictions based on different PDF sets to the observed number of events in the ZEUS data is presented. It is applied to compare predictions from the most commonly used PDFs to published ZEUS data at high Bjorken x . A wide variation is found in the ability of the PDFs to predict the observed results. A scheme for including the ZEUS highx data in future PDF extractions is discussed.
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