130 research outputs found
Sustainable production of glucaric acid from corn stover via glucose oxidation: An assessment of homogeneous and heterogeneous catalytic oxidation production routes
Glucaric acid is being used increasingly as a food additive, corrosion inhibitor, in deicing, and in detergents, and is also a potential starting material for the production of adipic acid, the key monomer for nylon-66. This work describes a techno-economic analysis of a potential bio-based process for the production of pure glucaric acid from corn stover (biomass). Two alternative routes for oxidation of glucose to glucaric acid are considered: via heterogeneous catalytic oxidation with air, and by homogeneous glucose oxidation using nitric acid. Techno-economic and lifecycle assessments (TEA, LCA) are made for both oxidation routes and cover the entire process from biomass to pure crystalline glucaric acid that can be used as a starting material for the production of valuable chemicals. This is the first TEA of pure glucaric acid production incorporating ion exchange and azeotropic evaporation below 50 °C to avoid lactone formation. The developed process models were simulated in Aspen Plus V9. The techno-economic assessment shows that both production routes are economically viable leading to minimum selling prices of glucaric acid of ∼2.91/kg for the heterogeneous catalytic route and the homogeneous glucose oxidation route respectively. It is shown that the heterogeneous catalytic oxidation route is capable of achieving a 22% lower environmental impact than the homogeneous glucose oxidation route. Opportunities for further improvement in sustainable glucaric acid production at industrial scale are identified and discussed
High frequency of tumor cells with nuclear Egr-1 protein expression in human bladder cancer is associated with disease progression
<p>Abstract</p> <p>Background</p> <p>Egr-1 (early growth response-1 transcription factor) has been proposed to be involved in invasion and metastasis processes of human bladder cancer, but Egr-1 protein expression levels in human bladder cancer have not been investigated. In the present study we investigated the expression levels of Egr-1 protein in early stages of human bladder cancer and correlated it to later progression.</p> <p>Methods</p> <p>Expression of Egr-1 protein in human bladder cancer was examined by immunohistochemistry, on a tissue microarray constructed from tumors from 289 patients with non-muscle invasive urothelial bladder cancer.</p> <p>Results</p> <p>The frequency of tumor cells with nuclear Egr-1 immunolabelling correlated to bladder cancer stage, grade and to later progression to muscle-invasive bladder cancer (T2-4). Stage T1 tumors exhibited significantly higher frequencies of tumor cells with nuclear Egr-1 immunolabelling than Ta tumors (P = 0.001). Furthermore, Kaplan-Meier survival analysis showed that a high frequency of tumor cells with nuclear Egr-1 immunolabelling was significantly associated with a higher risk of progression to stage T2-4 (log-rank test, P = 0.035). Tumor cells with nuclear Egr-1 immunolabelling were found to localize at the tumor front in some of the tumor biopsies.</p> <p>Conclusion</p> <p>The results from this study support a potential involvement of Egr-1 in the progression from non-muscle invasive bladder cancers to muscle invasive bladder cancer.</p
Echinoderms have bilateral tendencies
Echinoderms take many forms of symmetry. Pentameral symmetry is the major
form and the other forms are derived from it. However, the ancestors of
echinoderms, which originated from Cambrian period, were believed to be
bilaterians. Echinoderm larvae are bilateral during their early development.
During embryonic development of starfish and sea urchins, the position and the
developmental sequence of each arm are fixed, implying an auxological
anterior/posterior axis. Starfish also possess the Hox gene cluster, which
controls symmetrical development. Overall, echinoderms are thought to have a
bilateral developmental mechanism and process. In this article, we focused on
adult starfish behaviors to corroborate its bilateral tendency. We weighed
their central disk and each arm to measure the position of the center of
gravity. We then studied their turning-over behavior, crawling behavior and
fleeing behavior statistically to obtain the center of frequency of each
behavior. By joining the center of gravity and each center of frequency, we
obtained three behavioral symmetric planes. These behavioral bilateral
tendencies might be related to the A/P axis during the embryonic development of
the starfish. It is very likely that the adult starfish is, to some extent,
bilaterian because it displays some bilateral propensity and has a definite
behavioral symmetric plane. The remainder of bilateral symmetry may have
benefited echinoderms during their evolution from the Cambrian period to the
present
Olfactory function following open rhinoplasty: A 6-month follow-up study
<p>Abstract</p> <p>Background</p> <p>Patients undergoing any type of nasal surgery may experience degrees of postoperative olfactory dysfunction. We sought to investigate "when" the olfactory function recovers to its preoperative levels.</p> <p>Methods</p> <p>In this cohort design, 40 of 65 esthetic open rhinoplasty candidates with equal gender distribution, who met the inclusion criteria, were assessed for their olfactory function using the Smell Identification Test (SIT) with 40 familiar odors in sniffing bottles. All the patients were evaluated for the SIT scores preoperatively and postoperatively (at week 1, week 6, and month 6).</p> <p>Results</p> <p>At postoperative week one, 87.5% of the patients had anosmia, and the rest exhibited at least moderate levels of hyposmia. The anosmia, which was the dominant pattern at postoperative week 1, resolved and converted to various levels of hyposmia, so that no one at postoperative week 6 showed any such complain. At postoperative week six, 85% of the subjects experienced degrees of hyposmia, almost all being mild to moderate. At postoperative six month, the olfactory function had already reverted to the preoperative levels: no anosmia or moderate to severe hyposmia. A repeated ANOVA was indicative of significant differences in the olfactory function at the different time points. According to our post hoc Benfronney, the preoperative scores had a significant difference with those at postoperative week 1, week 6, but not with the ones at month 6.</p> <p>Conclusion</p> <p>Esthetic open rhinoplasty may be accompanied by some degrees of postoperative olfactory dysfunction. Patients need a time interval of 6 weeks to 6 months to fully recover their baseline olfactory function.</p
Visual detail about the body modulates tactile localisation biases
The localisation of tactile stimuli requires the integration of visual and somatosensory inputs within an internal representation of the body surface, and is prone to consistent bias. Joints may play a role in segmenting such internal body representations, and may therefore influence tactile localisation biases, although the nature of this influence remains unclear. Here, we investigate the relationship between conceptual knowledge of joint locations and tactile localisation biases on the hand. In one task, participants localised tactile stimuli applied to the dorsum of their hand. A distal localisation bias was observed in all participants, consistent with previous results. We also manipulated the availability of visual information during this task, to determine whether the absence of this information could account for the distal bias observed here and by Mancini and colleagues (2011). The observed distal bias increased in magnitude when visual information was restricted, without a corresponding decrease in precision. In a separate task, the same participants indicated, from memory, knuckle locations on a silhouette image of their hand. Analogous distal biases were also seen in the knuckle localisation task. The accuracy of conceptual joint knowledge was not correlated with tactile localisation bias magnitude, although a similarity in observed bias direction suggests that both tasks may rely on a common, higher-order body representation. These results also suggest that distortions of conceptual body representation may be more common in healthy individuals than previously thought
Different physiology of interferon-α/-γ in models of liver regeneration in the rat
Liver regeneration may take place after liver injury through replication of hepatocytes or hepatic progenitor cells called oval cells. Interferons (IFN) are natural cytokines with pleiotrophic effects including antiviral and antiproliferative actions. No data are yet available on the physiology and cellular source of natural IFNs during liver regeneration. To address this issue, we have analyzed the levels and biologic activities of IFN-α/IFN-γ in two models of partial hepatectomy. After 2/3rd partial hepatectomy (PH), hepatic levels of IFN-α and IFN-γ declined transiently in contrast to a transient increase of the IFN-γ serum level. After administration of 2-acetylaminofluorene and partial hepatectomy (AAF/PH model), however, both IFN-α and IFN-γ expression were up-regulated in regenerating livers. Again, the IFN-γ serum level was transiently increased. Whereas hepatic IFN-γ was up-regulated early (day 1–5), but not significantly, in the AAF/PH model, IFN-α was significantly up-regulated at later time points in parallel to the peak of oval cell proliferation (days 7–9). Biological activity of IFN-α was shown by activation of IFN-α-specific signal transduction and induction of IFN-α specific-gene expression. We found a significant infiltration of the liver with inflammatory monocyte-like mononuclear phagocytes (MNP) concomitant to the frequency of oval cells. We localized IFN-α production only in MNPs, but not in oval cells. These events were not observed in normal liver regeneration after standard PH. We conclude that IFN-γ functions as an acute-phase cytokine in both models of liver regeneration and may constitute a systemic component of liver regeneration. IFN-α was increased only in the AAF/PH model, and was associated with proliferation of oval cells. However, oval cells seem not to be the source of IFN-α. Instead, inflammatory MNP infiltrating AAF/PH-treated livers produce IFN-α. These inflammatory MNPs may be involved in the regulation of the oval cell compartment through local expression of cytokines, including IFN-α
Functional MRI of working memory and selective attention in vibrotactile frequency discrimination
Processing of spatial-frequency altered faces in schizophrenia: Effects of illness phase and duration
Low spatial frequency (SF) processing has been shown to be impaired in people with schizophrenia, but it is not clear how this varies with clinical state or illness chronicity. We compared schizophrenia patients (SCZ, n534), first episode psychosis patients (FEP, n522), and healthy controls (CON, n535) on a gender/facial discrimination task. Images were either unaltered (broadband spatial frequency, BSF), or had high or low SF information removed (LSF and HSF conditions, respectively). The task was performed at hospital admission and discharge for patients, and at corresponding time points for controls. Groups were matched on visual acuity. At admission, compared to their BSF performance, each group was significantly worse with low SF stimuli, and most impaired with high SF stimuli. The level of impairment at each SF did not depend on group. At discharge, the SCZ group performed more poorly in the LSF condition than the other groups, and showed the greatest degree of performance decline collapsed over HSF and LSF conditions, although the latter finding was not significant when controlling for visual acuity. Performance did not change significantly over time for any group. HSF processing was strongly related to visual acuity at both time points for all groups. We conclude the following: 1) SF processing abilities in schizophrenia are relatively stable across clinical state; 2) face processing abnormalities in SCZ are not secondary to problems processing specific SFs, but are due to other known difficulties constructing visual representations from degraded information; and 3) the relationship between HSF processing and visual acuity, along with known SCZ- and medication-related acuity reductions, and the elimination of a SCZ-related impairment after controlling for visual acuity in this study, all raise the possibility that some prior findings of impaired perception in SCZ may be secondary to acuity reductions
NRF2 Activation Restores Disease Related Metabolic Deficiencies in Olfactory Neurosphere-Derived Cells from Patients with Sporadic Parkinson's Disease
Extent: 14p.Background: Without appropriate cellular models the etiology of idiopathic Parkinson’s disease remains unknown. We recently reported a novel patient-derived cellular model generated from biopsies of the olfactory mucosa (termed olfactory neurosphere-derived (hONS) cells) which express functional and genetic differences in a disease-specific manner. Transcriptomic analysis of Patient and Control hONS cells identified the NRF2 transcription factor signalling pathway as the most differentially expressed in Parkinson’s disease. Results: We tested the robustness of our initial findings by including additional cell lines and confirmed that hONS cells from Patients had 20% reductions in reduced glutathione levels and MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)- 2-(4-sulfophenyl)-2H-tetrazolium, inner salt] metabolism compared to cultures from healthy Control donors. We also confirmed that Patient hONS cells are in a state of oxidative stress due to higher production of H2O2 than Control cultures. siRNA-mediated ablation of NRF2 in Control donor cells decreased both total glutathione content and MTS metabolism to levels detected in cells from Parkinson’s Disease patients. Conversely, and more importantly, we showed that activation of the NRF2 pathway in Parkinson’s disease hONS cultures restored glutathione levels and MTS metabolism to Control levels. Paradoxically, transcriptomic analysis after NRF2 pathway activation revealed an increased number of differentially expressed mRNAs within the NRF2 pathway in L-SUL treated Patient-derived hONS cells compared to L-SUL treated Controls, even though their metabolism was restored to normal. We also identified differential expression of the PI3K/AKT signalling pathway, but only post-treatment. Conclusions: Our results confirmed NRF2 as a potential therapeutic target for Parkinson’s disease and provided the first demonstration that NRF2 function was inducible in Patient-derived cells from donors with uniquely varied genetic backgrounds. However, our results also demonstrated that the response of PD patient-derived cells was not co-ordinated in the same way as in Control cells. This may be an important factor when developing new therapeutics.Anthony L. Cook, Alejandra M. Vitale, Sugandha Ravishankar, Nicholas Matigian, Greg T. Sutherland, Jiangou Shan, Ratneswary Sutharsan, Chris Perry, Peter A. Silburn, George D. Mellick, Murray L. Whitelaw, Christine A. Wells, Alan Mackay-Sim and Stephen A. Woo
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