813 research outputs found
Access route selection for percutaneous coronary intervention among Vietnamese patients: Implications for in-hospital costs and outcomes
Background:Little is known about rates of access site (transradial (TRI) or transfemoral (TFI)) preference for percutaneous coronary intervention (PCI) and in-hospital costs of patients undergoing these procedures in lower-and middle-countries. Here, we report on access site use, in-hospital costs and outcomes of patients undergoing PCI in Vietnam.Methods:Information from 868 patients were included in the cohort of 1022 patients recruited into the first PCI registry in Vietnam. The total hospital costs and in-hospital outcomes of patients undergoing TRI and TFI were compared. Hospital costs were obtained from the hospital admission system, and major adverse cardiac events, major bleeding events and length of stay were identified through review of medical records.Findings:TRI was the dominant access site for interventionists (694/868 patients). The TFI group reported more lesions of the left main artery, more previous coronary artery bypass grafts and previous PCI in comparison with the TRI group (all p Interpretations:Among patients undergoing PCI, TRI was associated with lower costs and favourable clinical outcomes relative to TFI
Predicting cell types and genetic variations contributing to disease by combining GWAS and epigenetic data
Genome-wide association studies (GWASs) identify single nucleotide polymorphisms (SNPs) that are enriched in individuals suffering from a given disease. Most disease-associated SNPs fall into non-coding regions, so that it is not straightforward to infer phenotype or function; moreover, many SNPs are in tight genetic linkage, so that a SNP identified as associated with a particular disease may not itself be causal, but rather signify the presence of a linked SNP that is functionally relevant to disease pathogenesis. Here, we present an analysis method that takes advantage of the recent rapid accumulation of epigenomics data to address these problems for some SNPs. Using asthma as a prototypic example; we show that non-coding disease-associated SNPs are enriched in genomic regions that function as regulators of transcription, such as enhancers and promoters. Identifying enhancers based on the presence of the histone modification marks such as H3K4me1 in different cell types, we show that the location of enhancers is highly cell-type specific. We use these findings to predict which SNPs are likely to be directly contributing to disease based on their presence in regulatory regions, and in which cell types their effect is expected to be detectable. Moreover, we can also predict which cell types contribute to a disease based on overlap of the disease-associated SNPs with the locations of enhancers present in a given cell type. Finally, we suggest that it will be possible to re-analyze GWAS studies with much higher power by limiting the SNPs considered to those in coding or regulatory regions of cell types relevant to a given disease
Probing the electronic structure of pure and doped CeMIn(5) (M=Co,Rh,Ir) crystals with nuclear quadrupolar resonance
We report calculations of the electric-field gradients (EFGs) in pure and doped CeMIn(5) (M=Co, Rh, and Ir) compounds and compare with experiment. The degree to which the Ce 4f electron is localized is treated within various models: the local-density approximation, generalized gradient approximation (GGA), GGA+U, and 4f-core approaches. We find that there is a correlation between the observed EFG and whether the 4f electron participates in the band formation or not. We also find that the EFG evolves linearly with Sn doping in CeRhIn(5), suggesting the electronic structure is modified by doping. In contrast, the observed EFG in CeCoIn(5) doped with Cd changes little with doping. These results indicate that nuclear quadrupolar resonance is a sensitive probe of electronic structure.772
Breast imaging technology: Application of magnetic resonance imaging to angiogenesis in breast cancer
Magnetic resonance imaging (MRI) techniques enable vascular function to be mapped with high spatial resolution. Current methods for imaging in breast cancer are described, and a review of recent studies that compared dynamic contrast-enhanced MRI with histopathological indicators of tumour vascular status is provided. These studies show correlation between in vivo dynamic contrast measurements and in vitro histopathology. Dynamic contrast enhanced MRI is also being applied to assessment of the response of breast tumours to treatment
Interleukin-6 gene (IL-6): a possible role in brain morphology in the healthy adult brain
Background: Cytokines such as interleukin 6 (IL-6) have been implicated in dual functions in neuropsychiatric disorders. Little is known about the genetic predisposition to neurodegenerative and neuroproliferative properties of cytokine genes. In this study the potential dual role of several IL-6 polymorphisms in brain morphology is investigated. Methodology: In a large sample of healthy individuals (N = 303), associations between genetic variants of IL-6 (rs1800795; rs1800796, rs2069833, rs2069840) and brain volume (gray matter volume) were analyzed using voxel-based morphometry (VBM). Selection of single nucleotide polymorphisms (SNPs) followed a tagging SNP approach (e.g., Stampa algorigthm), yielding a capture 97.08% of the variation in the IL-6 gene using four tagging SNPs. Principal findings/results: In a whole-brain analysis, the polymorphism rs1800795 (−174 C/G) showed a strong main effect of genotype (43 CC vs. 150 CG vs. 100 GG; x = 24, y = −10, z = −15; F(2,286) = 8.54, puncorrected = 0.0002; pAlphaSim-corrected = 0.002; cluster size k = 577) within the right hippocampus head. Homozygous carriers of the G-allele had significantly larger hippocampus gray matter volumes compared to heterozygous subjects. None of the other investigated SNPs showed a significant association with grey matter volume in whole-brain analyses. Conclusions/significance: These findings suggest a possible neuroprotective role of the G-allele of the SNP rs1800795 on hippocampal volumes. Studies on the role of this SNP in psychiatric populations and especially in those with an affected hippocampus (e.g., by maltreatment, stress) are warranted.Bernhard T Baune, Carsten Konrad, Dominik Grotegerd, Thomas Suslow, Eva Birosova, Patricia Ohrmann, Jochen Bauer, Volker Arolt, Walter Heindel, Katharina Domschke, Sonja Schöning, Astrid V Rauch, Christina Uhlmann, Harald Kugel and Udo Dannlowsk
Quantum Criticality in Heavy Fermion Metals
Quantum criticality describes the collective fluctuations of matter
undergoing a second-order phase transition at zero temperature. Heavy fermion
metals have in recent years emerged as prototypical systems to study quantum
critical points. There have been considerable efforts, both experimental and
theoretical, which use these magnetic systems to address problems that are
central to the broad understanding of strongly correlated quantum matter. Here,
we summarize some of the basic issues, including i) the extent to which the
quantum criticality in heavy fermion metals goes beyond the standard theory of
order-parameter fluctuations, ii) the nature of the Kondo effect in the quantum
critical regime, iii) the non-Fermi liquid phenomena that accompany quantum
criticality, and iv) the interplay between quantum criticality and
unconventional superconductivity.Comment: (v2) 39 pages, 8 figures; shortened per the editorial mandate; to
appear in Nature Physics. (v1) 43 pages, 8 figures; Non-technical review
article, intended for general readers; the discussion part contains more
specialized topic
Stabilization of angiotensin-(1-7) by key substitution with a cyclic non-natural amino acid
Angiotensin-(1-7) [Ang-(1-7)], a heptapeptide hormone of the renin-angiotensin-aldosterone system (RAAS), is a promising candidate as a treatment for cancer that reflects its antiproliferative and anti-angiogenic properties. However, the peptide’s therapeutic potential is limited by the short half-life and low bioavailability resulting from rapid enzymatic metabolism by peptidases including angiotensin-converting enzyme (ACE) and dipeptidyl peptidase 3 (DPP 3). We report the facile assembly of three novel Ang-(1-7) analogues by solid-phase peptide synthesis which incorporates the cyclic non-natural δ-amino acid ACCA. The analogues containing the ACCA substitution at the site of ACE cleavage exhibit complete resistance to human ACE, while substitution at the DDP3 cleavage site provided stability against DPP 3 hydrolysis. Furthermore, the analogues retain the anti-proliferative properties of Ang-(1-7) against the 4T1 and HT-1080 cancer cell lines. These results suggest that ACCA-substituted Ang-(1-7) analogues which show resistance against proteolytic degradation by peptidases known to hydrolyze the native heptapeptide may be novel therapeutics in the treatment of cancer
Quantitative proteomic analysis of the influence of lignin on biofuel production by Clostridium acetobutylicum ATCC 824
Background: Clostridium acetobutylicum has been a focus of research because of its ability to produce high-value
compounds that can be used as biofuels. Lignocellulose is a promising feedstock, but the lignin–cellulose–hemicellulose
biomass complex requires chemical pre-treatment to yield fermentable saccharides, including cellulose-derived
cellobiose, prior to bioproduction of acetone–butanol–ethanol (ABE) and hydrogen. Fermentation capability is
limited by lignin and thus process optimization requires knowledge of lignin inhibition. The effects of lignin on cellular
metabolism were evaluated for C. acetobutylicum grown on medium containing either cellobiose only or cellobiose
plus lignin. Microscopy, gas chromatography and 8-plex iTRAQ-based quantitative proteomic technologies were
applied to interrogate the effect of lignin on cellular morphology, fermentation and the proteome.
Results: Our results demonstrate that C. acetobutylicum has reduced performance for solvent production when
lignin is present in the medium. Medium supplemented with 1 g L−1
of lignin led to delay and decreased solvents
production (ethanol; 0.47 g L−1
for cellobiose and 0.27 g L−1
for cellobiose plus lignin and butanol; 0.13 g L−1
for cellobiose
and 0.04 g L−1
for cellobiose plus lignin) at 20 and 48 h, respectively, resulting in the accumulation of acetic
acid and butyric acid. Of 583 identified proteins (FDR < 1 %), 328 proteins were quantified with at least two unique
peptides. Up- or down-regulation of protein expression was determined by comparison of exponential and stationary
phases of cellobiose in the presence and absence of lignin. Of relevance, glycolysis and fermentative pathways were
mostly down-regulated, during exponential and stationary growth phases in presence of lignin. Moreover, proteins
involved in DNA repair, transcription/translation and GTP/ATP-dependent activities were also significantly affected
and these changes were associated with altered cell morphology.
Conclusions: This is the first comprehensive analysis of the cellular responses of C. acetobutylicum to lignin at metabolic
and physiological levels. These data will enable targeted metabolic engineering strategies to optimize biofuel
production from biomass by overcoming limitations imposed by the presence of lignin
Cold and heterogeneous T cell repertoire is associated with copy number aberrations and loss of immune genes in small-cell lung cancer
Small-cell lung cancer (SCLC) is speculated to harbor complex genomic intratumor heterogeneity (ITH) associated with high recurrence rate and suboptimal response to immunotherapy. Here, using multi-region whole exome/T cell receptor (TCR) sequencing as well as immunohistochemistry, we reveal a rather homogeneous mutational landscape but extremely cold and heterogeneous TCR repertoire in limited-stage SCLC tumors (LS-SCLCs). Compared to localized non-small cell lung cancers, LS-SCLCs have similar predicted neoantigen burden and genomic ITH, but significantly colder and more heterogeneous TCR repertoire associated with higher chromosomal copy number aberration (CNA) burden. Furthermore, copy number loss of IFN-γ pathway genes is frequently observed and positively correlates with CNA burden. Higher mutational burden, higher T cell infiltration and positive PD-L1 expression are associated with longer overall survival (OS), while higher CNA burden is associated with shorter OS in patients with LS-SCLC
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