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81.
Coulson-Thomas VJ Coulson-Thomas YM Gesteira TF de Paula CA Mader AM Waisberg J Pinhal MA Friedl A Toma L Nader HB 《Cell and tissue research》2011,346(2):223-236
During cancer cell growth many tumors exhibit various grades of desmoplasia, unorganized production of fibrous or connective
tissue, composed mainly of collagen fibers and myofibroblasts. The accumulation of an extracellular matrix (ECM) surrounding
tumors directly affects cancer cell proliferation, migration and spread; therefore the study of desmoplasia is of vital importance.
Stromal fibroblasts surrounding tumors are activated to myofibroblasts and become the primary producers of ECM during desmoplasia.
The composition, density and organization of this ECM accumulation play a major role on the influence desmoplasia has upon
tumor cells. In this study, we analyzed desmoplasia in vivo in human colorectal carcinoma tissue, detecting an up-regulation of collagen I, collagen IV and collagen V in human colorectal
cancer desmoplastic reaction. These components were then analyzed in vitro co-cultivating colorectal cancer cells (Caco-2 and HCT116) and fibroblasts utilizing various co-culture techniques. Our findings
demonstrate that direct cell-cell contact between fibroblasts and colorectal cancer cells evokes an increase in ECM density,
composed of unorganized collagens (I, III, IV and V) and proteoglycans (biglycan, fibromodulin, perlecan and versican). The
desmoplastic collagen fibers were thick, with an altered orientation, as well as deposited as bundles. This increased ECM
density inhibited the migration and invasion of the colorectal tumor cells in both 2D and 3D co-culture systems. Therefore
this study sheds light on a possible restricting role desmoplasia could play in colorectal cancer invasion. 相似文献
82.
Tarnaris A Toma AK Chapman MD Petzold A Keir G Kitchen ND Watkins LD 《Neurochemical research》2011,36(3):528-532
The rostrocaudal gradient (RCG) of markers present in cerebrospinal fluid (CSF) has not been studied adequately due to lack of appropriate control populations and ethical restrictions. The aim of this study is to understand the rostrocaudal gradient of CSF biomarkers. We contacted a study comparing CSF levels of seven biomarkers from cisternal (rostral) and lumbar (caudal) CSF obtained from patients with trigeminal neuralgia and tension-type headache. The RCGs of CSF/serum albumin ratio, 8-isoprostane. GFAP, total tau and beta amyloid protein were higher than one. The RCGs of lactate, VEGF and the heavy chain of neurofilament protein were lower than one. The study provides new values for several commonly examined markers of cisternal CSF. Knowledge of the RCG gradient of different CSF markers is important in interpreting studies reporting ventricular CSF values. 相似文献
83.
Bordignon V Bultrini S Prignano G Sperduti I Piperno G Bonifati C Filippetti M Toma L Latini A Di Cecio M Giuliani A Vocaturo A Trento E D' Agosto G Francesconi F Cataldo A Vento A Cilenti V Berardesca E Ameglio F Cordiali Fei P Ensoli F 《Journal of biological regulators and homeostatic agents》2011,25(2):213-220
The early diagnosis and treatment of individuals harboring M. tuberculosis is key to ensuring the effectiveness of health programs aimed at the elimination of tuberculosis (TB). Monitoring for TB also has other important health care implications for the related immune pathology caused by the chronic inflammatory response to M. tuberculosis. Moreover, the recent introduction of biologic therapies for the treatment of several immune-mediated inflammatory diseases has shown unexpected high frequencies of reactivation of latent TB. The present cross-sectional study is aimed at estimating the prevalence of latent tuberculosis infection (LTBI) in different groups of subjects, either undergoing a routine program of screening for TB or a clinical monitoring of autoimmune or lung disorders, by analyzing their immune response in vitro to a pool of different M. tuberculosis antigens through an IFN-gamma-release assay (IGRA). We consecutively tested 1,644 subjects including health care workers (931), healthy immigrants from different countries (93), patients with a diagnosis of psoriasis (405), patients with lung inflammatory disease (60) or lung neoplasia (32) and a group of HIV-1 infected Italian subjects (120). The prevalence of IGRAs positive responses among health care workers was 8.9 percent. In comparison, significantly higher frequencies were found in healthy immigrant subjects (33.3%), similar to those found in inflammatory broncho-pneumopathies (34.5%) or lung cancer (29.6%). Interestingly, an unexpected high prevalence was also found in patients affected by psoriasis (18.0%), while HIV-infected subjects had values comparable to those of health care workers (10.8%). An age cut-off was determined and applied for each group by receiver operating characteristic (ROC) curves in order to perform the statistical analysis among age-comparable groups. Multivariate analysis showed that the age and clinical conditions such as having a diagnosis of psoriasis or a lung inflammatory disease were independent risk factors for developing an IGRA positive response. This study highlights an unprecedented high prevalence of IGRA positive responses among patients affected by psoriasis and emphasizes the need for a preliminary assessment of LTBI before the administration of any biologic therapy based on cytokine antagonists such as anti-TNF-alpha. Moreover, screening for LTBI should be routinely performed in the presence of a chronic pulmonary disease. 相似文献
84.
Netto CG Nakamatsu EH Netto LE Novak MA Zuin A Nakamura M Araki K Toma HE 《Journal of inorganic biochemistry》2011,105(5):738-744
Thioredoxin (Trx1), a very important protein for regulating intracellular redox reactions, was immobilized on iron oxide superparamagnetic nanoparticles previously coated with 3-aminopropyltriethoxysilane (APTS) via covalent coupling using the EDC (1-ethyl-3-{3-dimethylaminopropyl}carbodiimide) method. The system was extensively characterized by atomic force microscopy, vibrational and magnetic techniques. In addition, gold nanoparticles were also employed to probe the exposed groups in the immobilized enzyme based on the SERS (surface enhanced Raman scattering) effect, confirming the accessibility of the cysteines residues at the catalytic site. For the single coated superparamagnetic nanoparticle, by monitoring the enzyme activity with the Ellman reagent, DTNB = 5,5′-dithio-bis(2-15 nitrobenzoic acid), an inhibitory effect was observed after the first catalytic cycle. The inhibiting effect disappeared after the application of an additional silicate coating before the APTS treatment, reflecting a possible influence of unprotected iron-oxide sites in the redox kinetics. In contrast, the doubly coated system exhibited a normal in-vitro kinetic activity, allowing a good enzyme recovery and recyclability. 相似文献
85.
Ana Mladenovic Zeljko Markovic Sandra Radenković Bojana Orbovic Vladimir Mirčetić Goran Tomašek 《Central European Journal of Biology》2014,9(10):967-972
Background: The aim of this study was to present an original technique of low-dose coronary computerized tomographyangiography (CCTA) for the evaluation and early diagnosis of coronary occlusive disease (COD) and to compare from this technique of CCTA with those resulting from the latest conventional angiography and multidetector computerized tomography units. Methodology: The study included 820 CCTA exams of patients with COD (average age 61 +/? 7 years), with a follow-up exam in 204 male (39%) and 62 female (20%) patients with hemodynamically insignificant coronary occlusion. Exams were performed using a 64-slice computerized tomography (CT) unit using electrocardiography (ECG)-triggering and individual settings (voltage of the x-ray tube and effective tube-current) based on each patient’s body mass index. Exponential dose for each exam was defined. Results:There was a statistically significant progression in the number of patients in whom occlusion of one of 3 coronary arteries occurred in hemodynamically significant occlusive disease (occlusion of more than 50% of lumen) — 60 of 204 males and 12 of 62 females (p<0.0001 and p<0.001). The mid-effective radiation dose during CCTA exams was 1.9+/-0.7mSv (range of 0.9 to 3.9 mSv). Conclusion: Prospective ECG-triggering allowed for low-dose CCTA exams while still enabling high diagnostic accuracy in evaluating patients with COD. The technique used in this study resulted in 2 times less the exponential dose than conventional angiography. 相似文献
86.
87.
Sequence of the gene encoding an alkaline serine proteinase of Bacillus pumilus TYO-67 总被引:3,自引:0,他引:3
The complete nucleotide sequence of the gene encoding an alkaline serine proteinase (aprP) of Bacillus pumilus TYO-67 was determined. The sequence analysis showed an open reading frame of 1,149 bp (383 amino acids) that encoded a signal peptide consisting of 29 residues and a propeptide of 79 residues. The deduced 3 amino acid residues, D32, H64, and S221, were identical with 3 essential amino acids in the catalytic center of subtilases. The sequence around these residues revealed that APRP was a new member of the true subtilisin subgroup of the subtilisin family. The highest homology was found in subtilisin NAT at 64.4% in the DNA sequence. The residue S189 of APRP was different from those of other subtilases. 相似文献
88.
89.
Cilia‐localized LKB1 regulates chemokine signaling,macrophage recruitment,and tissue homeostasis in the kidney
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Kamile Lukas Abhijeet P Todkar Manuel Knoll Toma A Yakulov Alexis Hofherr Oliver Kretz Martin Helmstädter Wilfried Reichardt Simone Braeg Tom Aschman Annette Merkle Dietmar Pfeifer Verónica I Dumit Marie‐Claire Gubler Roland Nitschke Tobias B Huber Fabiola Terzi Jörn Dengjel Florian Grahammer Michael Köttgen Hauke Busch Melanie Boerries Gerd Walz Antigoni Triantafyllopoulou E Wolfgang Kuehn 《The EMBO journal》2018,37(15)
Polycystic kidney disease (PKD) and other renal ciliopathies are characterized by cysts, inflammation, and fibrosis. Cilia function as signaling centers, but a molecular link to inflammation in the kidney has not been established. Here, we show that cilia in renal epithelia activate chemokine signaling to recruit inflammatory cells. We identify a complex of the ciliary kinase LKB1 and several ciliopathy‐related proteins including NPHP1 and PKD1. At homeostasis, this ciliary module suppresses expression of the chemokine CCL2 in tubular epithelial cells. Deletion of LKB1 or PKD1 in mouse renal tubules elevates CCL2 expression in a cell‐autonomous manner and results in peritubular accumulation of CCR2+ mononuclear phagocytes, promoting a ciliopathy phenotype. Our findings establish an epithelial organelle, the cilium, as a gatekeeper of tissue immune cell numbers. This represents an unexpected disease mechanism for renal ciliopathies and establishes a new model for how epithelial cells regulate immune cells to affect tissue homeostasis. 相似文献
90.
Moritoshi Iwagami Noppadon Tangpukdee Polrat Wilairatana Srivicha Krudsood Le Duc Dao Shusuke Nakazawa Muth Sinuon Duong Socheat Junko Yasuoka Masamine Jimba Hisami Watanabe Jun Kobayashi Hiromu Toma Viengxay Vanisaveth Bouasy Hongvanthong Paul T. Brey Shigeyuki Kano 《Parasitology international》2018,67(6):816-823
Malaria morbidity and mortality have decreased gradually in the Greater Mekong Subregion (GMS). Presently, WHO sets a goal to eliminate malaria by 2030 in the GMS. However, drug-resistant malaria has been reported from several endemic areas. To achieve the goal of elimination, the status of the emergence and spread of drug resistance should be monitored. In this study, the genotype of the Plasmodium falciparum chloroquine (CQ) resistance transporter gene (pfcrt) and 6 microsatellite DNA loci flanking the gene were examined. P. falciparum isolates (n?=?136) was collected from malaria patients in Thailand (n?=?50, 2002–2005), Vietnam (n?=?39, 2004), Laos (n?=?15, 2007) and Cambodia (n?=?32, 2009). Amino acid sequences at codons 72–76 on the gene were determined. All of the isolates from Thailand were CQ-resistant (CVIET), as were all of the isolates from Cambodia (CVIET, CVIDT). Thirteen of the 15 isolates (87%) from Laos were CQ-resistant (CVIET, CVIDT), whereas the other 2 (13%) were CQ-susceptible (CVMNK). In contrast, 27 of the 39 isolates (69%) from Vietnam were CQ-susceptible (CVMNK), whereas the other 12 (31%) were CQ-resistant (CVIET, CVIDT, CVMDT) or mixed (CVMNK/CVIDT). The mean of expected heterozygosity of the microsatellite loci was 0.444 in the Thai population, 0.482 in the Cambodian population, and 0.734 in the Vietnamese population. Genetic diversity in the Thai population was significantly lower than that in the Vietnamese population. These results suggested that chloroquine selective pressure on P. falciparum populations is heterogeneous in the GMS. Therefore, further examination to understand the mechanisms behind the emergence and spread of drug-resistant malaria are needed. 相似文献