Growth of dense CNT on the multilayer graphene film by the microwave plasma enhanced chemical vapor deposition technique and their field emission properties

Catalyst assisted carbon nanotubes (CNTs) were grown on multilayer graphene (MLG) on copper and silicon substrates by the microwave plasma enhanced chemical vapor deposition technique. The transmission of the MLG was found to vary between 82 to 91.8% with the increase of deposition time. Scanning electron microscopy depicted that the MLG film survived at the deposition condition of CNTs with the appearance of the damaged structure due to the plasma. Growth of CNTs was controlled by adjusting the flow rates of methane gas. The density of carbon nanotubes was observed to increase with a higher supply of methane gas. It was observed that the field emission properties were improved with the increased density of CNTs on MLG. The lowest turn-on field was found to be 1.6 V mu m(-1) 1 accompanied with the highest current density of 2.8 mA cm(-2) for the CNTs with the highest density. The findings suggested that the field emission properties can be tuned by changing the density of CNTs

Nuclear magnetic resonance in conjunction with functional genomics suggests mitochondrial dysfunction in a murine model of cancer cachexia

Cancer patients commonly suffer from cachexia, a syndrome in which tumors induce metabolic changes in the host that lead to massive loss in skeletal muscle mass. Using a preclinical mouse model of cancer cachexia, we tested the hypothesis that tumor inoculation causes a reduction in ATP synthesis and genome-wide aberrant expression in skeletal muscle. Mice implanted with Lewis lung carcinomas were examined by in vivo 31P nuclear magnetic resonance (NMR). We examined ATP synthesis rate and the expression of genes that play key-regulatory roles in skeletal muscle metabolism. Our in vivo NMR results showed reduced ATP synthesis rate in tumor-bearing (TB) mice relative to control (C) mice, and were cross-validated with whole genome transcriptome data showing atypical expression levels of skeletal muscle regulatory genes such as peroxisomal proliferator activator receptor γ coactivator 1 ß (PGC-1ß), a major regulator of mitochondrial biogenesis and, mitochondrial uncoupling protein 3 (UCP3). Aberrant pattern of gene expression was also associated with genes involved in inflammation and immune response, protein and lipid catabolism, mitochondrial biogenesis and uncoupling, and inadequate oxidative stress defenses, and these effects led to cachexia. Our findings suggest that reduced ATP synthesis is linked to mitochondrial dysfunction, ultimately leading to skeletal muscle wasting and thus advance our understanding of skeletal muscle dysfunction suffered by cancer patients. This study represents a new line of research that can support the development of novel therapeutics in the molecular medicine of skeletal muscle wasting. Such therapeutics would have wide-spread applications not only for cancer patients, but also for many individuals suffering from other chronic or endstage diseases that exhibit muscle wasting, a condition for which only marginally effective treatments are currently available

Nuclear magnetic resonance in conjunction with functional genomics suggests mitochondrial dysfunction in a murine model of cancer cachexia

Cancer patients commonly suffer from cachexia, a syndrome in which tumors induce metabolic changes in the host that lead to massive loss in skeletal muscle mass. Using a preclinical mouse model of cancer cachexia, we tested the hypothesis that tumor inoculation causes a reduction in ATP synthesis and genome-wide aberrant expression in skeletal muscle. Mice implanted with Lewis lung carcinomas were examined by in vivo 31P nuclear magnetic resonance (NMR). We examined ATP synthesis rate and the expression of genes that play key-regulatory roles in skeletal muscle metabolism. Our in vivo NMR results showed reduced ATP synthesis rate in tumor-bearing (TB) mice relative to control (C) mice, and were cross-validated with whole genome transcriptome data showing atypical expression levels of skeletal muscle regulatory genes such as peroxisomal proliferator activator receptor γ coactivator 1 ß (PGC-1ß), a major regulator of mitochondrial biogenesis and, mitochondrial uncoupling protein 3 (UCP3). Aberrant pattern of gene expression was also associated with genes involved in inflammation and immune response, protein and lipid catabolism, mitochondrial biogenesis and uncoupling, and inadequate oxidative stress defenses, and these effects led to cachexia. Our findings suggest that reduced ATP synthesis is linked to mitochondrial dysfunction, ultimately leading to skeletal muscle wasting and thus advance our understanding of skeletal muscle dysfunction suffered by cancer patients. This study represents a new line of research that can support the development of novel therapeutics in the molecular medicine of skeletal muscle wasting. Such therapeutics would have wide-spread applications not only for cancer patients, but also for many individuals suffering from other chronic or endstage diseases that exhibit muscle wasting, a condition for which only marginally effective treatments are currently available

Elimination of the vesicular acetylcholine transporter in the forebrain causes hyperactivity and deficits in spatial memory and long-term potentiation

Basal forebrain cholinergic neurons, which innervate the hippocampus and cortex, have been implicated in many forms of cognitive function. Immunolesion-based methods in animal models have been widely used to study the role of acetylcholine (ACh) neurotransmission in these processes, with variable results. Cholinergic neurons have been shown to release both glutamate and ACh, making it difficult to deduce the specific contribution of each neurotransmitter on cognition when neurons are eliminated. Understanding the precise roles of ACh in learning and memory is critical because drugs that preserve ACh are used as treatment for cognitive deficits. It is therefore important to define which cholinergic-dependent behaviors could be improved pharmacologically. Here we investigate the contributions of forebrain ACh on hippocampal synaptic plasticity and cognitive behavior by selective elimination of the vesicular ACh transporter, which interferes with synaptic storage and release of ACh. We show that elimination of vesicular ACh transporter in the hippocampus results in deficits in long-term potentiation and causes selective deficits in spatial memory. Moreover, decreased cholinergic tone in the forebrain is linked to hyperactivity, without changes in anxiety or depression-related behavior. These data uncover the specific contribution of forebrain cholinergic tone for synaptic plasticity and behavior. Moreover, these experiments define specific cognitive functions that could be targeted by cholinergic replacement therapy

Structural, Field Emission and Ammonia Gas Sensing Properties of Multiwalled Carbon Nanotube-Graphene Like Hybrid Films Deposited by Microwave Plasma Enhanced Chemical Vapor Deposition Technique

This paper reports the direct deposition of multiwalled carbon nanotube (MWCNT)-graphene like hybrid films on nickel substrate using a 2.45 GHz microwave plasma enhanced chemical vapor deposition (MW PECVD) system in the temperature range of 500-700 degrees C at 20 Torr pressure. The films have been characterized by Raman spectra, high resolution transmission electron microscope (HRTEM), scanning electron microscope, high resolution X-ray diffraction and contact angle measurement. Raman spectroscopy and HRTEM reveal the formation of MWCNT and graphene like hybrid carbon sheet structures. The effect of processing temperature on the field emission properties of MWCNT-graphene like hybrid films has been investigated. Field emission measurement reveals that the turn-on field decrease and the emission current density increase with the increase of deposition temperature. The rambutan structure of MWCNT formed at 700 degrees C is responsible for the improvement in the field emission properties. The film deposited at 700 degrees C shows fast response and recovery time of 40 and 96 s, respectively, for ammonia gas sensing due to the high surface area of the film. It has also been found that the hydrophobic surface of the film helps to perform the gas sensing in the humid environment

Association of genetic polymorphisms in the interleukin-10 promoter with risk of prostate cancer in Chinese

<p>Abstract</p> <p>Background</p> <p>Recent studies identified an increased risk of prostate cancer (PCa) in Caucasian men harboring polymorphisms of genes involved in innate immunity and inflammation. This study was designed to assess whether single nucleotide polymorphisms in the IL-10 promoter play a role in predisposing individuals to PCa in a Chinese population.</p> <p>Methods</p> <p>We genotyped three SNPs of the <it>IL-10 </it>promoter (-1082A/G, -819T/C and -592A/C) using polymerase chain reaction-restriction fragment length polymorphism analysis in 262 subjects with PCa and 270 age-matched healthy controls. Odds ratio and 95% confidence interval were determined by logistic regression for the associations between IL-10 genotypes and haplotypes with the risk of PCa and advanced PCa grade.</p> <p>Results</p> <p>No significant differences in allele frequency or genotype distribution were observed for any of the <it>IL-10 </it>SNPs between PCa patients and control subjects. Significantly higher frequencies of -1082G, -819C and -592C allele and GCC haplotype were observed, however, in early stage patients in comparison to advanced PCa patients (for -1082 G, 13.9% vs 6.1%, OR = 2.48, <it>P </it>= 0.005; for -819 C 40.3% vs 30.8%, OR = 1.51, <it>P </it>= 0.043; for -512C, 40.3% vs 30.8%, OR = 1.51, <it>P </it>= 0.043; and for haplotype GCC 11.1%vs 5.1%, OR = 2.66, P = 0.008, respectively).</p> <p>Conclusions</p> <p>Our results identify that <it>IL-10 </it>promoter polymorphisms might not be a risk factor for PCa in Chinese cohorts, but rather incidence of polymorphisms associates with PCa grade, suggesting that IL-10 expression may impact PCa progression.</p

Differential Functions of Splicing Factors in Mammary Transformation and Breast Cancer Metastasis

Misregulation of alternative splicing is a hallmark of human tumors, yet to what extent and how it contributes to malignancy are only beginning to be unraveled. Here, we define which members of the splicing factor SR and SR-like families contribute to breast cancer and uncover differences and redundancies in their targets and biological functions. We identify splicing factors frequently altered in human breast tumors and assay their oncogenic functions using breast organoid models. We demonstrate that not all splicing factors affect mammary tumorigenesis in MCF-10A cells. Specifically, the upregulation of SRSF4, SRSF6, or TRA2beta disrupts acinar morphogenesis and promotes cell proliferation and invasion in MCF-10A cells. By characterizing the targets of these oncogenic splicing factors, we identify shared spliced isoforms associated with well-established cancer hallmarks. Finally, we demonstrate that TRA2beta is regulated by the MYC oncogene, plays a role in metastasis maintenance in vivo, and its levels correlate with breast cancer patient survival

A Meta-Analysis of Caspase 9 Polymorphisms in Promoter and Exon Sequence on Cancer Susceptibility

BACKGROUND: Caspases are important regulators and executioners in apoptosis pathway and have been defined as either tumor suppressors or oncogenes. Polymorphisms in promoter and exon of caspase 9 were shown to confer genetic susceptibility to multiple cancers, but the results were inconsistent. To accomplish a more precise estimation of the relationship, a meta-analysis was performed. METHODOLOGY/PRINCIPAL FINDINGS: We assessed published studies of the association between caspase 9 polymorphisms and cancer risk from nine studies with 5,528 subjects for rs4645978, six studies with 2,403 subjects for rs105276 and two studies for rs4645981. Overall meta-analysis indicated that no evidence of an association between rs4645978 and cancers was found. Through the stratified analysis, statistically significant reduced cancer risks were observed among Caucasians (AG vs AA: OR = 0.81, 95% CI = 0.66-0.99, P(heterogeneity) = 0.150 and the dominant model: OR = 0.86, 95% CI = 0.75-0.99, P(heterogeneity) = 0.290) and prostate cancer. As for rs105276, Ex5+32G>A polymorphism was found with protective effect in overall meta-analysis (AA vs GG: OR = 0.75, 95% CI = 0.60-0.92, P(heterogeneity) = 0.887; A vs G: OR = 0.85, 95% CI = 0.77-0.95, P(heterogeneity) = 0.739 and the recessive model: OR = 0.68, 95% CI = 0.56-0.82, P(heterogeneity) = 0.309) and Asians group. While for rs4645981, a statistically significant increase in risk of lung cancer was shown in Asians (T vs C: OR = 1.23, 95% CI = 1.07-1.42, P(heterogeneity) = 0.399 and the dominant model: OR = 1.22, 95% CI = 1.04-1.43, P(heterogeneity) = 0.660). CONCLUSIONS/SIGNIFICANCE: Our meta-analysis suggests that the caspase 9 rs4645978 most likely contributes to decreased susceptibility to cancer in Caucasians and prostate cancer. The A allele of rs105276 might be a protective factor for cancer, especially for Asians. However, it seems that rs4645981 confers increased susceptibility to lung cancer in Asians

A Quorum Sensing Regulated Small Volatile Molecule Reduces Acute Virulence and Promotes Chronic Infection Phenotypes

A significant number of environmental microorganisms can cause serious, even fatal, acute and chronic infections in humans. The severity and outcome of each type of infection depends on the expression of specific bacterial phenotypes controlled by complex regulatory networks that sense and respond to the host environment. Although bacterial signals that contribute to a successful acute infection have been identified in a number of pathogens, the signals that mediate the onset and establishment of chronic infections have yet to be discovered. We identified a volatile, low molecular weight molecule, 2-amino acetophenone (2-AA), produced by the opportunistic human pathogen Pseudomonas aeruginosa that reduces bacterial virulence in vivo in flies and in an acute mouse infection model. 2-AA modulates the activity of the virulence regulator MvfR (multiple virulence factor regulator) via a negative feedback loop and it promotes the emergence of P. aeruginosa phenotypes that likely promote chronic lung infections, including accumulation of lasR mutants, long-term survival at stationary phase, and persistence in a Drosophila infection model. We report for the first time the existence of a quorum sensing (QS) regulated volatile molecule that induces bistability phenotype by stochastically silencing acute virulence functions in P. aeruginosa. We propose that 2-AA mediates changes in a subpopulation of cells that facilitate the exploitation of dynamic host environments and promote gene expression changes that favor chronic infections