1,409 research outputs found
Dependent Lung Opacity at Thin-Section CT: Evaluation by Spirometrically-Gated CT of the Influence of Lung Volume
ObjectiveTo evaluate the influence of lung volume on dependent lung opacity seen at thin-section CT.Materials and methodsIn thirteen healthy volunteers, thin-section CT scans were performed at three levels (upper, mid, and lower portion of the lung) and at different lung volumes (10, 30, 50, and 100% vital capacity), using spirometric gated CT. Using a three-point scale, two radiologists determined whether dependent opacity was present, and estimated its degree. Regional lung attenuation at a level 2 cm above the diaphragm was determined using semiautomatic segmentation, and the diameter of a branch of the right lower posterior basal segmental artery was measured at each different vital capacity.ResultsAt all three anatomic levels, dependent opacity occurred significantly more often at lower vital capacities (10, 30%) than at 100% vital capacity (p = 0.001). Visually estimated dependent opacity was significantly related to regional lung attenuation (p < 0.0001), which in dependent areas progressively increased as vital capacity decreased (p < 0.0001). The presence of dependent opacity and regional lung attenuation of a dependent area correlated significantly with increased diameter of a segmental arterial branch (r = 0.493 and p = 0.0002; r = 0.486 and p = 0.0003, respectively).ConclusionVisual estimation and CT measurements of dependent opacity obtained by semiautomatic segmentation are significantly influenced by lung volume and are related to vascular diameter
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Expression of Heterologous OsDHAR Gene Improves Glutathione (GSH)-Dependent Antioxidant System and Maintenance of Cellular Redox Status in Synechococcus elongatus PCC 7942.
An excess of reactive oxygen species (ROS) can cause severe oxidative damage to cellular components in photosynthetic cells. Antioxidant systems, such as the glutathione (GSH) pools, regulate redox status in cells to guard against such damage. Dehydroascorbate reductase (DHAR, EC 1.8.5.1) catalyzes the glutathione-dependent reduction of oxidized ascorbate (dehydroascorbate) and contains a redox active site and glutathione binding-site. The DHAR gene is important in biological and abiotic stress responses involving reduction of the oxidative damage caused by ROS. In this study, transgenic Synechococcus elongatus PCC 7942 (TA) was constructed by cloning the Oryza sativa L. japonica DHAR (OsDHAR) gene controlled by an isopropyl β-D-1-thiogalactopyranoside (IPTG)-inducible promoter (Ptrc) into the cyanobacterium to study the functional activities of OsDHAR under oxidative stress caused by hydrogen peroxide exposure. OsDHAR expression increased the growth of S. elongatus PCC 7942 under oxidative stress by reducing the levels of hydroperoxides and malondialdehyde (MDA) and mitigating the loss of chlorophyll. DHAR and glutathione S-transferase activity were higher than in the wild-type S. elongatus PCC 7942 (WT). Additionally, overexpression of OsDHAR in S. elongatus PCC 7942 greatly increased the glutathione (GSH)/glutathione disulfide (GSSG) ratio in the presence or absence of hydrogen peroxide. These results strongly suggest that DHAR attenuates deleterious oxidative effects via the glutathione (GSH)-dependent antioxidant system in cyanobacterial cells. The expression of heterologous OsDHAR in S. elongatus PCC 7942 protected cells from oxidative damage through a GSH-dependent antioxidant system via GSH-dependent reactions at the redox active site and GSH binding site residues during oxidative stress
Highly Conductive Graphene/Ag Hybrid Fibers for Flexible Fiber-Type Transistors
Mechanically robust, flexible, and electrically conductive textiles are highly suitable for use in wearable electronic applications. In this study, highly conductive and flexible graphene/Ag hybrid fibers were prepared and used as electrodes for planar and fiber-type transistors. The graphene/Ag hybrid fibers were fabricated by the wet-spinning/drawing of giant graphene oxide and subsequent functionalization with Ag nanoparticles. The graphene/Ag hybrid fibers exhibited record-high electrical conductivity of up to 15,800 S cm(-1). As the graphene/Ag hybrid fibers can be easily cut and placed onto flexible substrates by simply gluing or stitching, ion gel-gated planar transistors were fabricated by using the hybrid fibers as source, drain, and gate electrodes. Finally, fibertype transistors were constructed by embedding the graphene/Ag hybrid fiber electrodes onto conventional polyurethane monofilaments, which exhibited excellent flexibility (highly bendable and rollable properties), high electrical performance (mu(h) = 15.6 cm(2) V-1 s(-1), I-on/I-off > 10(4)), and outstanding device performance stability (stable after 1,000 cycles of bending tests and being exposed for 30 days to ambient conditions). We believe that our simple methods for the fabrication of graphene/Ag hybrid fiber electrodes for use in fiber-type transistors can potentially be applied to the development all-organic wearable devices.111912Ysciescopu
Expression of OsTPX Gene Improves Cellular Redox Homeostasis and Photosynthesis Efficiency in Synechococcus elongatus PCC 7942
Cyanobacterial 2-Cys peroxiredoxin (thioredoxin peroxidase, TPX) comprises a family of thiol antioxidant enzymes critically involved in cell survival under oxidative stress. In our previous study, a putative TPX was identified using a proteomics analysis of rice (Oryza sativa L. japonica, OsTPX) seedlings exposed to oxidative stress. This OsTPX gene is structurally similar to the Synechococcus elongatus TPX gene in the highly conserved redox-active disulfide bridge (Cys114, Cys236) and other highly conserved regions. In the present study, the OsTPX gene was cloned into rice plants and S. elongatus PCC 7942 strain to study hydrogen peroxide (H2O2) stress responses. The OsTPX gene expression was confirmed using semi-quantitative RT-PCR and western blot analysis. The OsTPX gene expression increased growth under oxidative stress by decreasing reactive oxygen species and malondialdehyde level. Additionally, the OsTPX gene expression in S. elongatus PCC 7942 (OT) strain exhibited a reduced loss of chlorophyll and enhanced photosynthesis efficiency under H2O2 stress, thereby increasing biomass yields twofold compared with that of the control wild type (WT) strain. Furthermore, redox balance, ion homeostasis, molecular chaperone, and photosynthetic systems showed upregulation of some genes in the OT strain than in the WT strain by RNA-Seq analysis. Thus, OsTPX gene expression enhances oxidative stress tolerance by increasing cell defense regulatory networks through the cellular redox homeostasis in the rice plants and S. elongatus PCC 7942
Modelling The Cancer Growth Process By Stochastic Delay Diffferential Equations Under Verhults And Gompertz's Law
In this paper, the uncontrolled environmental factors are perturbed into the intrinsic growth rate factor of deterministic equations of the growth process. The growth process under two different laws which are Verhults and Gompertz’s law are considered, thus leading to
stochastic delay differential equations (SDDEs) of logistic and Gompertzian, respectively. Gompertzian deterministic model has been proved to fit well the clinical data of cancerous growth, however the performance of stochastic model towards clinical data is yet to be confirmed. The prediction quality of logistic and Gompertzian SDDEs are evaluating by comparing the simulated results with the clinical data of cervical cancer growth. The parameter estimation of stochastic models is computed by using simulated maximum likelihood method. We adopt 4-stage stochastic Runge-Kutta to simulate the solution of stochastic models
Tropical forest conversion to rubber plantation affects soil micro- & mesofaunal community & diversity
Tropical rainforests play important roles in carbon sequestration and are hot spots for biodiversity.
Tropical forests are being replaced by rubber (Hevea brasiliensis) plantations, causing widespread
concern of a crash in biodiversity. Such changes in aboveground vegetation might have stronger
impacts on belowground biodiversity. We studied tropical rainforest fragments and derived rubber
plantations at a network of sites in Xishuangbanna, China, hypothesizing a major decrease in diversity
with conversion to plantations. We used metabarcoding of the 18S rRNA gene and recovered 2313
OTUs, with a total of 449 OTUs shared between the two land-use types. The most abundant phyla
detected were Annelida (66.4% reads) followed by arthropods (15.5% reads) and nematodes (8.9%
reads). Of these, only annelids were significantly more abundant in rubber plantation. Taken together,
α- and β-diversity were significantly higher in forest than rubber plantation. Soil pH and spatial distance
explained a significant portion of the variability in phylogenetic community structure for both land-use
types. Community assembly was primarily influenced by stochastic processes. Overall it appears that
forest replacement by rubber plantation results in an overall loss and extensive replacement of soil
micro- and mesofaunal biodiversity, which should be regarded as an additional aspect of the impact of
forest conversion
Long-term effect of stereotactic body radiation therapy for primary hepatocellular carcinoma ineligible for local ablation therapy or surgical resection. Stereotactic radiotherapy for liver cancer
<p>Abstract</p> <p>Background</p> <p>We evaluated the long-term effect of stereotactic body radiation therapy (SBRT) for primary small hepatocellular carcinoma (HCC) ineligible for local therapy or surgery.</p> <p>Methods</p> <p>Forty-two HCC patients with tumors ≤ 100 cc and ineligible for local ablation therapy or surgical resection were treated with SBRT: 30-39 Gy with a prescription isodose range of 70-85% (median 80%) was delivered daily in three fractions. Median tumor volume was 15.4 cc (3.0-81.8) and median follow-up duration 28.7 months (8.4-49.1).</p> <p>Results</p> <p>Complete response (CR) for the in-field lesion was initially achieved in 59.6% and partial response (PR) in 26.2% of patients. Hepatic out-of-field progression occurred in 18 patients (42.9%) and distant metastasis developed in 12 (28.6%) patients. Overall in-field CR and overall CR were achieved in 59.6% and 33.3%, respectively. Overall 1-year and 3-year survival rates were 92.9% and 58.6%, respectively. In-field progression-free survival at 1 and 3 years was 72.0% and 67.5%, respectively. Patients with smaller tumor had better in-field progression-free survival and overall survival rates (<32 cc vs. ≥32 cc, <it>P </it>< 0.05). No major toxicity was encountered but one patient died with extrahepatic metastasis and radiation-induced hepatic failure.</p> <p>Conclusions</p> <p>SBRT is a promising noninvasive-treatment for small HCC that is ineligible for local treatment or surgical resection.</p
Effect of a fixed-dose combination of Telmisartan/S-amlodipine on circadian blood pressure compared with Telmisartan monotherapy: TENUVA-BP study
Abstract
Background
This study evaluated the circadian efficacy of a telmisartan 40 mg/S-amlodipine 2.5 mg fixed-dose combination (Telmisartan40/S-Amlodipine2.5) compared to telmisartan 80 mg (Telmisartan80) in patients with essential hypertension who did not respond to 2–4 weeks treatment with telmisartan 40 mg.
Methods
Eligible patients with essential hypertension (clinic mean sitting systolic blood pressure [MSSBP] ≥140 mmHg, or ≥ 130 mmHg in those with diabetes mellitus or chronic kidney disease) were randomly assigned to Telmisartan40/S-Amlodipine2.5 or Telmisartan80 for 8 weeks. All patients underwent ambulatory BP monitoring (ABPM) at baseline and 8 weeks later. Primary endpoints were changes in mean 24-h SBP and DBP on 24-h ABPM from baseline after 8 weeks. Secondary endpoints were changes in daytime, nighttime, and morning SBP and DBP, and clinic MSSBP and MSDBP.
Results
A total of 316 Korean patients were enrolled, 217 patients were randomized to treatment, and 192 patients completed the study. Compared to Telmisartan80, Telmisartan40/S-Amlodipine2.5 showed significantly better reductions in 24-h mean SBP and DBP after 8 weeks. Telmisartan40/S-Amlodipine2.5 also significantly reduced secondary endpoints compared to Telmisartan80. Among 15 adverse events (7 [Telmisartan40/S-Amlodipine2.5] and 8 [Telmisartan80]), there were five adverse drug reactions; 14 events were mild, and none were identified with significant between-group differences.
Conclusions
Telmisartan40/S-Amlodipine2.5 was tolerable and more effective than Telmisartan80 in lowering 24-h mean ambulatory BP in patients with essential hypertension not responding adequately to Telmisartan40. Our findings support the fact that the combination of S-amlodipine with telmisartan is more appropriate than increasing the dose of telmisartan monotherapy.
Trial registration
ClinicalTrials.gov
,
NCT02231788
. Registered 4 September 2014
Sublingual Immunization with M2-Based Vaccine Induces Broad Protective Immunity against Influenza
The ectodomain of matrix protein 2 (M2e) of influenza A virus is a rationale target antigen candidate for the development of a universal vaccine against influenza as M2e undergoes little sequence variation amongst human influenza A strains. Vaccine-induced M2e-specific antibodies (Abs) have been shown to display significant cross-protective activity in animal models. M2e-based vaccine constructs have been shown to be more protective when administered by the intranasal (i.n.) route than after parenteral injection. However, i.n. administration of vaccines poses rare but serious safety issues associated with retrograde passage of inhaled antigens and adjuvants through the olfactory epithelium. In this study, we examined whether the sublingual (s.l.) route could serve as a safe and effective alternative mucosal delivery route for administering a prototype M2e-based vaccine. The mechanism whereby s.l. immunization with M2e vaccine candidate induces broad protection against infection with different influenza virus subtypes was explored.A recombinant M2 protein with three tandem copies of the M2e (3M2eC) was expressed in Escherichia coli. Parenteral immunizations of mice with 3M2eC induced high levels of M2e-specific serum Abs but failed to provide complete protection against lethal challenge with influenza virus. In contrast, s.l. immunization with 3M2eC was superior for inducing protection in mice. In the latter animals, protection was associated with specific Ab responses in the lungs.The results demonstrate that s.l. immunization with 3M2eC vaccine induced airway mucosal immune responses along with broad cross-protective immunity to influenza. These findings may contribute to the understanding of the M2-based vaccine approach to control epidemic and pandemic influenza infections
Genetic Polymorphisms of the Bovine NOV Gene Are Significantly Associated with Carcass Traits in Korean Cattle
The objective of this study was to investigate single nucleotide polymorphisms (SNPs) in the bovine nephroblastoma overexpressed (NOV) gene and to evaluate whether these polymorphisms affect carcass traits in the Korean cattle population. We resequenced to detect SNPs from 24 unrelated individuals and identified 19 SNPs within the full 8.4-kb gene, including the 1.5-kb promoter region. Of these 19 SNPs, four were selected for genotyping based on linkage disequilibrium (LD). We genotyped 429 steers to assess the associations of these four SNPs with carcass traits. Statistical analysis revealed that g.7801T>C and g.8379A>C polymorphisms in the NOV gene were associated with carcass weight (p = 0.012 and 0.008, respectively), and the g.2005A>G polymorphism was associated with the back fat thickness (BF) trait (p = 0.0001). One haplotype of the four SNPs (GGTA) was significantly associated with BF (p = 0.0005). Our findings suggest that polymorphisms in the NOV gene may be among the important genetic factors affecting carcass yield in beef cattle
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