447 research outputs found
The ancient phosphatidylinositol 3-kinase signaling system is a master regulator of energy and carbon metabolism in algae
Algae undergo a complete metabolic transformation under stress by arresting cell growth, inducing autophagy and hyperaccumulating biofuel precursors such as triacylglycerols and starch. However, the regulatory mechanisms behind this stress-induced transformation are still unclear. Here, we use biochemical, mutational, and “omics” approaches to demonstrate that PI3K signaling mediates the homeostasis of energy molecules and influences carbon metabolism in algae. In Chlamydomonas reinhardtii, the inhibition and knockdown (KD) of algal class III PI3K led to significantly decreased cell growth, altered cell morphology, and higher lipid and starch contents. Lipid profiling of wild-type and PI3K KD lines showed significantly reduced membrane lipid breakdown under nitrogen starvation (-N) in the KD. RNA-seq and network analyses showed that under -N conditions, the KD line carried out lipogenesis rather than lipid hydrolysis by initiating de novo fatty acid biosynthesis, which was supported by tricarboxylic acid cycle down-regulation and via acetyl-CoA synthesis from glycolysis. Remarkably, autophagic responses did not have primacy over inositide signaling in algae, unlike in mammals and vascular plants. The mutant displayed a fundamental shift in intracellular energy flux, analogous to that in tumor cells. The high free fatty acid levels and reduced mitochondrial ATP generation led to decreased cell viability. These results indicate that the PI3K signal transduction pathway is the metabolic gatekeeper restraining biofuel yields, thus maintaining fitness and viability under stress in algae. This study demonstrates the existence of homeostasis between starch and lipid synthesis controlled by lipid signaling in algae and expands our understanding of such processes, with biotechnological and evolutionary implications.Ministry of Science, ICT and Future Planning 2015M3A6A2065697Ministry of Oceans and Fisheries 2015018
Effect of few-walled carbon nanotube crystallinity on electron field emission property
We discuss the influence of few-walled carbon nanotubes (FWCNTs) treated with nitric acid and/or sulfuric acid on field emission characteristics. FWCNTs/tetraethyl orthosilicate (TEOS) thin film field emitters were fabricated by a spray method using FWCNTs/TEOS sol one-component solution onto indium tin oxide (ITO) glass. After thermal curing, they were found tightly adhered to the ITO glass, and after an activation process by a taping method, numerous FWCNTs were aligned preferentially in the vertical direction. Pristine FWCNT/ TEOS-based field emitters revealed higher current density, lower turn-on field, and a higher field enhancement factor than the oxidized FWCNTs-based field emitters. However, the unstable dispersion of pristine FWCNT in TEOS/N,N-dimethylformamide solution was not applicable to the field emitter fabrication using a spray method. Although the field emitter of nitric acid-treated FWCNT showed slightly lower field emission characteristics, this could be improved by the introduction of metal nanoparticles or resistive layer coating. Thus, we can conclude that our spray method using nitric acid-treated FWCNT could be useful for fabricating a field emitter and offers several advantages compared to previously reported techniques such as chemical vapor deposition and screen printing.ope
Two Cases of Systemic Capillary Leak Syndrome that were Treated with Pentastarch
Systemic capillary leak syndrome (SCLS) is a condition that's caused by the shift of fluid and protein from the intravascular space to the interstitial space as a result of repetitive episodes of capillary hyperpermeability. The pathogenesis of SCLS is still unclear, but there's recently been a report showing this syndrome in association with monoclonal gammopathy. This syndrome can be a fatal disease because cardiovascular collapse can occur in the initial capillary leak phase. Although theophylline, diuretics, terbutaline, steroids, calcium antagonist, Ginkgo biloba extracts and plasmapheresis have been suggested as medication, none of them have been proven to be effective. Considering that this disease is self-limiting, conservative treatment in the acute phase is believed to be very important. Because hypoalbuminemia is very a common manifestation of SCLS, Pentastarch, which has a higher molecular weight than albumin, could be efficient to prevent cardiovascular collapse. We used 10% Pentastarch during the acute SCLS attacks of 2 patients and the patients both showed a dramatic response. Pentastarch may be helpful to treat SCLS in its initial capillary leak phase by the elevating blood pressure, and this might contribute to somewhat decreasing the acute mortality of SCLS
Prognosis according to the timing of percutaneous coronary intervention in non-ST segment elevation myocardial infarction, based on the Korean Acute Myocardial Infarction Registry (KAMIR)
Background: Patients with acute coronary syndrome without ST-segment elevation (ACS-
-NSTE) are at risk for adverse cardiac events. Based on data in the Korean Acute Myocardial
Infarction Registry (KAMIR), we analyzed the prognosis according to the timing of percutaneous
coronary intervention (PCI) in patients with NSTEMI in Korea.
Methods and results: 2,455 patients with NSTEMI in KAMIR were classified according to
the time interval from the onset of cardiac symptoms to PCI. Patients in Group I underwent
PCI within 24 hours of the onset of symptoms; in Group II between 24 and 48 hours; and in
Group III after 48 hours. Major adverse cardiac events (MACEs) are defined as cardiac death,
non-cardiac death, myocardial infarction, revascularization and coronary-artery bypass graft
surgery. The MACEs were compared between groups. Of the 2,455 patients, 743 (30.2%) were
assigned to Group I, 583 (23.7%) to Group II, and 1,129 (45.9%) to Group III. The total
incidence of MACEs was higher in Group I than Group III, and similar between Groups I and
II (Group I: 15.1%, Group II: 14.4%, Group III: 11.6%, p = 0.053). The incidence of MACEs
in the intermediate TIMI risk score group had decreased as the intervention time was delayed.
Conclusions: The prognosis according to the timing of PCI in patients with NSTEMI was
similar based on the data in KAMIR. TIMI risk score was related to a high incidence of
MACEs. (Cardiol J 2011; 18, 4: 421–429
Novel Antidepressant-Like Activity of Caffeic Acid Phenethyl Ester Is Mediated by Enhanced Glucocorticoid Receptor Function in the Hippocampus
Caffeic acid phenethyl ester (CAPE) is an active component of propolis that has a variety of potential pharmacological effects. Although we previously demonstrated that propolis has antidepressant-like activity, the effect of CAPE on this activity remains unknown. The present study assessed whether treatment with CAPE (5, 10, and 20 µmol/kg for 21 days) has an antidepressant-like effect in mice subjected to chronic unpredictable stress via tail suspension (TST) and forced swim (FST) tests. CAPE administration induced behaviors consistent with an antidepressant effect, evidenced by decreased immobility in the TST and FST independent of any effect on serum corticosterone secretion. Western blots, conducted subsequent to behavioral assessment, revealed that CAPE significantly decreased glucocorticoid receptor phosphorylation at S234 (pGR(S234)), resulting in an increased pGR(S220/S234) ratio. We also observed negative correlations between pGR(S220)/(S234) and p38 mitogen-activated protein kinase (p38MAPK) phosphorylation, which was decreased by CAPE treatment. These findings suggest that CAPE treatment exerts an antidepressant-like effect via downregulation of p38MAPK phosphorylation, thereby contributing to enhanced GR function
Diseño e implementación de un sistema RFID para seguimiento de personas dependientes en el hogar
Este Trabajo Final de Grado se basa en el estudio, diseño, montaje y evaluación de un
sistema RFID (Radio Frequency IDentification) para el posicionamiento de personas
dependientes dentro de edificios, a fin de proporcionar un servicio a sus habitantes. El
primer paso es entender lo que son los sistemas RFID y estudiar casos de uso existentes.
Después, se estudia el funcionamiento de los lectores RFID disponibles y las etiquetas
(Tags) a rastrear; seguidamente se aprende a configurarlos y se diseña e implementa un
programa que pueda establecer una comunicación con los equipos y gestionar los
cálculos necesarios lo suficientemente rápido como para realizar un rastreo en tiempo
real. Una vez conseguido esto, se busca el método de cálculo de distancias y de
coordenadas lo más exacto posible y se corrigen los errores alcanzando la precisión
necesaria. Para ello, se realizan continuamente pruebas de rastreo y posicionamiento
tanto estáticos como en movimiento.In this final project a RFID (Radio Frequency IDentification) system is studied, designed,
implemented and evaluated. The system aims to track and position dependent people in
buildings, in order to provide different services to its inhabitants. Firstly, it is needed to
understand what RFID systems are, and study real-life use cases. Later, the operation
and configuration of the available RFID readers and tags is studied. Once this is
accomplished, a computer program is designed and implemented. This computer
program must communicate with the RFID equipment and perform the calculations fast
enough so that it is possible to track items in real time. Afterwards, errors are corrected
and the best formulas for calculating distances and coordinates are found, in order to
facilitate the required results and precision. Throughout the process, the system is
continuously tested with static and moving tracking and positioning.Catalá Adrama, L. (2015). Diseño e implementación de un sistema RFID para seguimiento de personas dependientes en el hogar. Universitat Politècnica de València. http://hdl.handle.net/10251/55170TFG
Profiling age-related epigenetic markers of stomach adenocarcinoma in young and old subjects
The purpose of our study is to identify epigenetic markers that are differently expressed in the stomach adenocarcinoma (STAD) condition. Based on data from The Cancer Genome Atlas (TCGA), we were able to detect an age-related difference in methylation patterns and changes in gene and miRNA expression levels in young (n = 14) and old (n = 70) STAD subjects. Our analysis identified 323 upregulated and 653 downregulated genes in old STAD subjects. We also found 76 miRNAs with age-related expression patterns and 113 differentially methylated genes (DMGs), respectively. Our further analysis revealed that significant upregulated genes (n = 35) were assigned to the cell cycle, while the muscle system process (n = 27) and cell adhesion-related genes (n = 57) were downregulated. In addition, by comparing gene and miRNA expression with methylation change, we identified that three upregulated genes (ELF3, IL1??, and MMP13) known to be involved in inflammatory responses and cell growth were significantly hypomethylated in the promoter region. We further detected target candidates for age-related, downregulated miRNAs (hsa-mir-124-3, hsa-mir-204, and hsa-mir-125b-2) in old STAD subjects. This is the first report of the results from a study exploring age-related epigenetic biomarkers of STAD using high-throughput data and provides evidence for a complex clinicopathological condition expressed by the age-related STAD progression. © the authors, publisher and licensee Libertas Academica Limitedopen
In Vivo
Platycodin D is a major pharmacological constituent of Platycodi radix and has showed various pharmacological activities through oxidative stress defense mechanisms. Here, possible antitumor, anticachexia, and immunomodulatory activities of platycodin D were observed on the H520 tumor cell-bearing athymic nude mice after confirming the in vitro cytotoxicity. Platycodin D was orally administered at dose levels of 200, 100, and 50 mg/kg, once a day for 35 days from 15 days after implantation. The results were compared with gemcitabine 160 mg/kg intraperitoneally treated mice (7-day intervals). Platycodin D showed favorable cytotoxic effects on the H520 cells, and also dose-dependently decreased the tumor volumes and weights with increases of apoptotic cells (caspase-3 and PARP immunopositive cells), iNOS and TNF-α immunoreactivities, decreases of COX-2 immunoreactivities in tumor masses. Platycodin D also showed dose-dependent immunostimulatory and anticachexia effects. Gemcitabine showed favorable cytotoxity against H520 tumor cell and related in vivo antitumor effects but aggravated the cancer related cachexia and immunosuppress in H520 tumor cell-bearing athymic nude mice. Taken together, it is considered that oral treatment of platycodin D has potent antitumor activities on H520 cells through direct cytotoxic effects, increases of apoptosis in tumor cells, and immunostimulatory effects and can be control cancer related cachexia
An Acute Postoperative Intractable Hyperventilation after an Endoscopic Third Ventriculostomy
This report describes a rare case of postoperative hyperventilation attack after an endoscopic third ventriculostomy in a 46-year-old woman. About 60 min after the termination of the operation, an intractable hyperventilation started with respiratory rate of 65 breaths/min and EtCO2, 16.3 mm Hg. Sedation with benzodiazepine, thiopental sodium, fentanyl, and propofol/remifentanil infusion was tried under a rebreathing mask at a 4 L/min of oxygen. With aggressive sedative challenges, ventilation pattern was gradually returned to normal during the 22 hrs of time after the surgery. A central neurogenic hyperventilation was suspected due to the stimulating central respiratory center by cold acidic irrigation solution during the neuroendoscopic procedure
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