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961.
962.
Xiaoru Sun Minghuan Zheng Miaomiao Zhang Mengjia Qian Yonghua Zheng Meiyi Li Dragos Cretoiu Chengshui Chen Luonan Chen Laurentiu M. Popescu Xiangdong Wang 《Journal of cellular and molecular medicine》2014,18(5):801-810
Telocytes (TCs) are a unique type of interstitial cells with specific, extremely long prolongations named telopodes (Tps). Our previous study showed that TCs are distinct from fibroblasts (Fbs) and mesenchymal stem cells (MSCs) as concerns gene expression and proteomics. The present study explores patterns of mouse TC‐specific gene profiles on chromosome 1. We investigated the network of main genes and the potential functional correlations. We compared gene expression profiles of mouse pulmonary TCs, MSCs, Fbs, alveolar type II cells (ATII), airway basal cells (ABCs), proximal airway cells (PACs), CD8+ T cells from bronchial lymph nodes (T‐BL) and CD8+ T cells from lungs (T‐LL). The functional and feature networks were identified and compared by bioinformatics tools. Our data showed that on TC chromosome 1, there are about 25% up‐regulated and 70% down‐regulated genes (more than onefold) as compared with the other cells respectively. Capn2, Fhl2 and Qsox1 were over‐expressed in TCs compared to the other cells, indicating that biological functions of TCs are mainly associated with morphogenesis and local tissue homoeostasis. TCs seem to have important roles in the prevention of tissue inflammation and fibrogenesis development in lung inflammatory diseases and as modulators of immune cell response. In conclusion, TCs are distinct from the other cell types. 相似文献
963.
964.
Yuriy Rebets Elke Brötz Bogdan Tokovenko Andriy Luzhetskyy 《Journal of industrial microbiology & biotechnology》2014,41(2):387-402
Actinomycetes genome sequencing and bioinformatic analyses revealed a large number of “cryptic” gene clusters coding for secondary metabolism. These gene clusters have the potential to increase the chemical diversity of natural products. Indeed, reexamination of well-characterized actinomycetes strains revealed a variety of hidden treasures. Growing information about this metabolic diversity has promoted further development of strategies to discover novel biologically active compounds produced by actinomycetes. This new task for actinomycetes genetics requires the development and use of new approaches and tools. Application of synthetic biology approaches led to the development of a set of strategies and tools to satisfy these new requirements. In this review, we discuss strategies and methods to discover small molecules produced by these fascinating bacteria and also discuss a variety of genetic instruments and regulatory elements used to activate secondary metabolism cryptic genes for the overproduction of these metabolites. 相似文献
965.
Alexandru F. Cri?an Cristian Oancea Bogdan Timar Ovidiu Fira-Mladinescu Alexandru Cri?an Voicu Tudorache 《PloS one》2014,9(7)
Background/Purpose
Chronic obstructive pulmonary disease (COPD), especially in severe forms, is commonly associated with multiple cognitive problems. Montreal Cognitive Assessment test (MoCA) is used to detect cognitive impairment evaluating several areas: visuospatial, memory, attention and fluency. Our study aim was to evaluate the impact of stable COPD and exacerbation (AECOPD) phases on cognitive status using MoCA questionnaire.Methods
We enrolled 39 patients (pts), smokers with COPD group D (30 stable and 9 in AECOPD) and 13 healthy subjects (control group), having similar level of education and no significant differences regarding the anthropometric measurements. We analyzed the differences in MoCA score between these three groups and also the correlation between this score and inflammatory markers.Results
Patients with AECOPD had a significant (p<0.001) decreased MoCA score (14.6±3.4) compared to stable COPD (20.2±2.4) and controls (24.2±5.8). The differences between groups were more accentuated for the language abstraction and attention (p<0.001) and delayed recall and orientation (p<0.001) sub-topics. No significant variance of score was observed between groups regarding visuospatial and naming score (p = 0.095). The MoCA score was significantly correlated with forced expiratory volume (r = 0.28) and reverse correlated with C-reactive protein (CRP) (r = −0.57), fibrinogen (r = −0.58), erythrocyte sedimentation rate (ESR) (r = −0.55) and with the partial pressure of CO2 (r = −0.47).Conclusions
According to this study, COPD significantly decreases the cognitive status in advanced and acute stages of the disease. 相似文献966.
Yuwei Zhang Rodrigo Calado Mahadev Rao Julie A. Hong Alan K. Meeker Bogdan Dumitriu Scott Atay Peter J. McCormick Susan H. Garfield Danny Wangsa Hesed M. Padilla-Nash Sandra Burkett Mary Zhang Tricia F. Kunst Nathan R. Peterson Sichuan Xi Suzanne Inchauste Nasser K. Altorki Alan G. Casson David G. Beer Curtis C. Harris Thomas Ried Neal S. Young David S. Schrump 《PloS one》2014,9(7)
967.
Ligia Petrica Adrian Vlad Gheorghe Gluhovschi Florica Gadalean Victor Dumitrascu Cristina Gluhovschi Silvia Velciov Flaviu Bob Daliborca Vlad Roxana Popescu Oana Milas Sorin Ursoniu 《PloS one》2014,9(11)
Background
There is an ongoing debate as to whether early diabetic nephropathy in Type 2 diabetes mellitus may be attributed to the glomerulus or to the proximal tubule. Urinary excretion of nephrin and vascular endothelial growth factor may increase even in the normoalbuminuria stage. In the course of diabetic nephropathy, the proximal tubule may be involved in the uptake of urinary nephrin and vascular endothelial growth factor.Materials and Methods
Two groups of consecutive Type 2 diabetes mellitus outpatients (38 normo-, 32 microalbuminuric) and 21 healthy subjects were enrolled in a cross-sectional study and evaluated concerning the relation of proximal tubule dysfunction with the podocyte biomarkers excretion, assessed by ELISA methods. The impact of advanced glycation end-products on this relation was also queried.Results
Urinary alpha1-microglobulin and kidney injury molecule-1 correlated with urinary albumin:creatinine ratio (R2 = 0.269; p<0.001; R2 = 0.125; p<0.001), nephrinuria (R2 = 0.529; p<0.001; R2 = 0.203; p<0.001), urinary vascular endothelial growth factor (R2 = 0.709; p<0.001; R2 = 0.360; p<0.001), urinary advanced glycation end-products (R2 = 0.578; p<0.001; R2 = 0.405; p<0.001), serum cystatin C (R2 = 0.130; p<0.001; R2 = 0.128; p<0.001), and glomerular filtration rate (R2 = 0.167; p<0.001; R2 = 0.166; p<0.001); nephrinuria and urinary vascular endothelial growth factor correlated with urinary albumin:creatinine ratio (R2 = 0.498; p<0.001; R2 = 0.227; p<0.001), urinary advanced glycation end-products (R2 = 0.251; p<0.001; R2 = 0.308; p<0.001), serum cystatin C (R2 = 0.157; p<0.001; R2 = 0.226; p<0.001), and glomerular filtration rate (R2 = 0.087; p = 0.007; R2 = 0.218; p<0.001).Conclusions
In Type 2 diabetes mellitus there is an association of proximal tubule dysfunction with podocyte damage biomarkers, even in the normoalbuminuria stage. This observation suggests a potential role of the proximal tubule in urinary nephrin and urinary vascular endothelial growth factor processing in early diabetic nephropathy, a fact which could be related to advanced glycation end-products intervention. Podocyte damage and proximal tubule dysfunction biomarkers could be validated as a practical approach to the diagnosis of early diabetic nephropathy by further studies on larger cohorts. 相似文献968.
Agnieszka Zmyslowska Bogdan Malkowski Wojciech Fendler Maciej Borowiec Karolina Antosik Piotr Gnys Dobromila Baranska Wojciech Mlynarski 《PloS one》2014,9(12)
Wolfram syndrome (WFS) is inherited as an autosomal recessive disease with main clinical features of diabetes mellitus, optic atrophy, diabetes insipidus and deafness. However, various neurological defects may also be detected. The aim of this study was to evaluate aspects of brain structure and function using PET-CT (positron emission tomography and computed tomography) and MRI (magnetic resonance imaging) in pediatric patients with WFS. Regional changes in brain glucose metabolism were measured using standardized uptake values (SUVs) based on images of (18F) fluorodeoxyglucose (FDG) uptake in 7 WFS patients aged 10.1–16.0 years (mean 12.9±2.4) and in 20 healthy children aged 3–17.9 years (mean 12.8±4.1). In all patients the diagnosis of WFS was confirmed by DNA sequencing of the WFS1 gene. Hierarchical clustering showed remarkable similarities of glucose uptake patterns among WFS patients and their differences from the control group. SUV data were subsequently standardized for age groups <13 years old and>13 years old to account for developmental differences. Reduced SUVs in WFS patients as compared to the control group for the bilateral brain regions such as occipital lobe (−1.24±1.20 vs. −0.13±1.05; p = 0.028) and cerebellum (−1.11±0.69 vs. −0.204±1.00; p = 0.036) were observed and the same tendency for cingulate (−1.13±1.05 vs. −0.15±1.12; p = 0.056), temporal lobe (−1.10±0.98 vs. −0.15±1.10; p = 0.057), parietal lobe (−1.06±1.20 vs. −0.08±1.08; p = 0.058), central region (−1.01±1.04 vs. −0.09±1.06; p = 0.060), basal ganglia (−1.05±0.74 vs. −0.20±1.07; p = 0.066) and mesial temporal lobe (−1.06±0.82 vs. −0.26±1.08; p = 0.087) was also noticed. After adjusting for multiple hypothesis testing, the differences in glucose uptake were non-significant. For the first time, regional differences in brain glucose metabolism among patients with WFS were shown using PET-CT imaging. 相似文献
969.
Ana Barbas Alma Popescu Carlos Frazão Cecília M. Arraiano Arsénio M. Fialho 《Biochemical and biophysical research communications》2013,430(1):218-224
Metabolic enzymes are usually characterized to have one specific function, and this is the case of UDP-glucose dehydrogenase that catalyzes the twofold NAD+-dependent oxidation of UDP-glucose into UDP-glucuronic acid. We have determined that this enzyme is also capable of participating in other cellular processes. Here, we report that the bacterial UDP-glucose dehydrogenase (UgdG) from Sphingomonas elodea ATCC 31461, which provides UDP-glucuronic acid for the synthesis of the exopolysaccharide gellan, is not only able to bind RNA but also acts as a ribonuclease. The ribonucleolytic activity occurs independently of the presence of NAD+ and the RNA binding site does not coincide with the NAD+ binding region. We have also performed the kinetics of interaction between UgdG and RNA. Moreover, computer analysis reveals that the N- and C-terminal domains of UgdG share structural features with ancient mitochondrial ribonucleases named MAR. MARs are present in lower eukaryotic microorganisms, have a Rossmannoid-fold and belong to the isochorismatase superfamily. This observation reinforces that the Rossmann structural motifs found in NAD+-dependent dehydrogenases can have a dual function working as a nucleotide cofactor binding domain and as a ribonuclease. 相似文献
970.
Krunoslav Sever Željko Škvorc Saša Bogdan Jozo Franjić Daniel Krstonošić Ivana Alešković 《Grana》2013,52(1):25-34
The impact of meteorological conditions on in vitro pollen germination and pollen tube growth during the initial phases of the development of male flowers in the Pedunculate Oak, Quercus robur, is studied. Phenological observations of male flowers and pollen sampling were performed on the field trial established with grafted Pedunculate Oak clones. During the investigation, weather conditions (absolute minimum and maximum daily air temperature, minimum absolute relative humidity of air and amount of precipitation) were recorded by an automatic meteorological station installed at the field trial. Influence of meteorological conditions on pollen germination and pollen tube growth was studied in the following stages of male flower: (I) during the last ten days of flower bud dormancy, (II) during swelling of the buds, (III) during bud burst and beginning of male catkins elongation, (IV) during the final stage of male flower catkins elongation. High temperatures and low relative air humidity during the bud burst and beginning of the male catkins elongation reduced pollen germination and pollen tube growth. Weather conditions did not significantly affect pollen germination and pollen tube growth during the swelling of flower buds, or in the final stage of male catkins elongation. 相似文献