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21.
Tobacco smoke, recognized as a major etiological factor for cancers of the upper aerodigestive tract, represents an abundant source of reactive oxygen species (ROS), which are believed to play a significant role in mutagenesis and carcinogenesis. An additional source of ROS in tissues exposed to tobacco smoke may be metabolic oxidation of polycyclic aromatic hydrocarbons (PAH). To investigate the relationships between oxidative DNA lesions and aromatic DNA adducts, six modified DNA bases 5-hydroxyuracil, 5-hydroxycytosine, 7,8-dihydro-8-oxoguanine, 7,8-dihydro-8-oxoadenine, 2,6-diamino-4-hydroxy-5-formamidopyrimidine and 4,6-diamino-5-formamidopyrimidine and the total level of PAH-related DNA adducts were measured in cancerous and the surrounding normal larynx tissues (68 subjects), using gas chromatography/isotope-dilution mass spectroscopy with selected ion monitoring and the 32 P-postlabeling-HPLC assay, respectively. The levels of oxidative DNA lesions in cancerous and adjacent tissue were comparable; the differences between the two types of tissue were significant only for 5-hydroxypyrimidines (slightly higher levels were observed in the adjacent tissue). Comparable levels of DNA lesions in cancerous and the surrounding normal tissues observed in the larynx tumors support a field cancerization theory. The surrounding tissues may still be recognized as normal by histological criteria. However, molecular alterations resulting from the chronic tobacco smoke exposure, which equally affects larynx epithelia, may lead to multiple premalignant lesions. Thus, a demonstration of similar levels of DNA damage in cancerous and the adjacent tissue could explain a frequent formation of secondary tumors in the larynx and the frequent recurrence in this type of cancer. A weak, but distinct effect of tumor grading and metastatic status was observed in both kinds of tissue in the case of 5-hydroxyuracil, 5-hydroxycytosine, 7,8-dihydro-8-oxoguanine, 7,8-dihydro-8-oxoadenine. This effect was displayed as a gradual shift in the data distribution toward high values from G1 through G2-G3 and from non-metastatic to metastatic tumors. Since the levels of oxidative DNA base modifications tended to increase with the tumor aggressiveness, we postulate that the oxidative DNA lesions increase genetic instability and thus contribute to tumor progression in laryngeal cancer. No associations between aromatic adduct levels and oxidative DNA lesions were present, suggesting that the metabolism of PAH does not contribute significantly to the oxidative stress in larynx tissues, remaining the tobacco smoke ROS as a major source of oxidative DNA damage in the exposed tissue.  相似文献   
22.
Strain DY59T, a Gram-positive non-motile bacterium, was isolated from soil in South Korea, and was characterized to determine its taxonomic position. Phylogenetic analysis based on the 16S rRNA gene sequence of strain DY59T revealed that the strain DY59T belonged to the family Deinococcaceae in the class Deinococci. The highest degree of sequence similarities of strain DY59T were found with Deinococcus radiopugnans KACC 11999T (99.0%), Deinococcus marmoris KACC 12218T (97.9%), Deinococcus saxicola KACC 12240T (97.0%), Deinococcus aerolatus KACC 12745T (96.2%), and Deinococcus frigens KACC 12220T (96.1%). Chemotaxonomic data revealed that the predominant fatty acids were iso-C15:0 (19.0%), C16:1 ω7c (17.7%), C15:1 ω6c (12.6%), iso-C17:0 (10.3%), and iso-C17:1 ω9c (10.3%). A complex polar lipid profile consisted of a major unknown phosphoglycolipid. The predominant respiratory quinone is MK-8. The cell wall peptidoglycan contained D-alanine, L-glutamic acid, glycine, and L-ornithine (di-amino acid). The novel strain showed resistance to gamma radiation, with a D10 value (i.e. the dose required to reduce the bacterial population by 10-fold) in excess of 5 kGy. Based on the phylogenetic, chemotaxonomic, and phenotypic data, strain DY59T (=KCTC 33033T =JCM 18581T) should be classified as a type strain of a novel species, for which the name Deinococcus swuensis sp. nov. is proposed.  相似文献   
23.
The risk of postoperative erectile dysfunction (ED) following radical prostatectomy (RP) is reported to be between 14% and 89%. With an increase in the detection of prostate cancer in younger men, there is a greater emphasis on the appropriate management of ED following RP. A number of options are available to manage ED after RP, including phosphodiesterase-5 inhibitors, intracorporeal injections, intraurethral alprostadil, and vacuum erection devices (VEDs). Penile rehabilitation programs are increasingly used to facilitate the return of natural postoperative erections; the VED is an ideal therapy given that it increases blood flow and oxygenation to the corpora to reverse the changes that result in ED after RP.Key words: Erectile dysfunction, Radical prostatectomy, Vacuum erection device, Penile rehabilitationProstate cancer is the most common cancer in men over the age of 50 years.1 When patients undergo a radical prostatectomy (RP), there is a risk of postoperative erectile dysfunction (ED). The incidence of ED following RP has been reported to be between 14% and 89%.2 With an increase in the detection of prostate cancer in younger men, there is a greater emphasis on the appropriate management of ED after RP. With an early diagnosis of prostate cancer, there is an increase in the rate of RP in younger men and the importance of ED as a quality-of-life issue has subsequently increased.2 There are a number of options available to manage ED after RP, including phosphodiesterase-5 (PDE-5) inhibitors, intracorporeal injections, intraurethral alprostadil, and vacuum erection devices (VEDs). Despite highly reported satisfaction and efficacy with VEDs, there is a move by some medical practitioners away from VEDs due to cost. But what evidence is there for VED success after prostatectomy and what role do VEDs have in penile rehabilitation after ED? We present current evidence and provide our recommendations based on the latest literature.  相似文献   
24.
Epithelial-mesenchymal-transition (EMT) is a key event for tumor cells to initiate metastasis which lead to switching of E-cadherin to N-cadherin. Resolvins are known to promote the resolution of inflammation and phagocytosis of macrophages. However, the role of resolvins in EMT of cancer is not known. Therefore, we examined the effects of resolvins on transforming growth factor, beta 1 (TGF-β1)-induced EMT. Expression of E-cadherin and N-cadherin in A549 lung cancer cells was evaluated by Western blot and confocal microscopy. Involvement of lipoxin A4 receptor/formyl peptide receptor 2 (ALX/FPR2) was examined by gene silencing. TGF-β1 induced expression of N-cadherin in A549 lung cancer cells, and resolvin D1 and D2 inhibited the expression of N-cadherin at low concentrations (1–100 nM). Resolvin D1 and D2 also suppressed the expression of zinc finger E-box binding homeobox 1 (ZEB1). The effects of resolvin D1 and D2 were confirmed in other lung cancer cell lines such as H838, H1299, and H1703. Resolvin D1 and D2 did not affect the proliferation of A549 lung cancer cells. Resolvin D1 and D2 also suppressed the TGF-β1-induced morphological change. Resolvin D1 and D2 also inhibited the TGF-β1-induced migration and invasion of A549 cells. Resolvin D1 is known to act via ALX/FPR2 and GPR32. Thus, we examined the involvement of ALX/FPR2 and GPR32 in the suppressive effects of resolvin D1 on TGF-β1-induced EMT of A549 cells. Gene silencing of ALX/FPR2 and GPR32 blocked the action of resolvin D1. Overexpression of ALX/FPR2 or GPR32 increased the effects of resolvin D1. These results suggest that resolvin D1 inhibited TGF-β1-induced EMT via ALX/FPR2 and GPR32 by reducing the expression of ZEB1.  相似文献   
25.
Background aimsMany rodent experiments and human studies on stem cell therapy have shown promising therapeutic approaches to liver diseases. We investigated the clinical outcomes of five patients with liver failure of various causes who received autologous CD34-depleted bone marrow-derived mononuclear cell (BM-MNC) transplantation, including mesenchymal stromal cells, through the hepatic artery.MethodsCD34-depleted BM-MNCs were obtained from five patients waiting for liver transplantation by bone marrow aspiration and using the CliniMACS CD34 Reagent System (Miltenyi Biotech, Bergisch Gladbach, Germany), and autologous hepatic artery infusion was performed. The causes of hepatic decompensation were hepatitis B virus (HBV), hepatitis C virus (HCV), propylthiouracil-induced toxic hepatitis and Wilson disease.ResultsSerum albumin levels improved 1 week after transplantation from 2.8 g/dL, 2.4 g/dL, 2.7 g/dL and 1.9 g/dL to 3.3 g/dL, 3.1 g/dL, 2.8 g/dL and 2.6 g/dL. Transient liver elastography data showed some change from 65 kPa, 33 kPa, 34.8 kPa and undetectable to 46.4 kPa, 19.8 kPa, 29.1 kPa and 67.8 kPa at 4 weeks after transplantation in a patient with Wilson disease, a patient with HCV, and two patients with HBV. Ascites decreased in two patients. One of the patients with HBV underwent liver transplantation 4 months after the infusion, and the hepatic progenitor markers (cytokeratin [CD]-7, CD-8, CD-9, CD-18, CD-19, c-Kit and epithelial cell adhesion molecule [EpCAM]) were highly expressed in the explanted liver.ConclusionsSerum albumin levels, liver stiffness, liver volume, subjective healthiness and quality of life improved in the study patients. Although these findings were observed in a small population, the results may suggest a promising future for autologous CD34-depleted BM-MNC transplantation as a bridge to liver transplantation in patients with liver failure.  相似文献   
26.

Introduction

Amplification of the ESR1 gene, coding for estrogen receptor alpha, was shown to predict responsiveness to tamoxifen, however its prognostic impact in breast cancer patients has not been thoroughly investigated. Other factors that could contribute to responsiveness to tamoxifen treatment are polymorphisms in ESR1 gene and genes involved in tamoxifen metabolism.The aim of this study was to assess the prognostic role of ESR1 gene dosage in a consecutive group of breast cancer patients and to correlate this feature with clinico-pathological factors. Additionally, ESR1 PvuII, CYP2C19*2 and UGT2B15*2 polymorphisms were analyzed in the tamoxifen-treated subgroup of patients.

Materials and Methods

Primary tumor samples from 281 stage I-III consecutive breast cancer patients were analyzed for ESR1 gene dosage using real-time PCR with locked nucleic acids hydrolysis probes. In the tamoxifen-treated subgroup of patients, ESR1 PvuII, CYP2C19*2 and UGT2B15*2 polymorphism in leukocytes genomic DNA were analyzed. Results were correlated with clinico-pathological factors and with disease-free survival (DFS) and overall survival (OS).

Results

ESR1 amplification (with a cut-off level of 2.0) was found in 12% of the entire group of breast cancer patients, and in 18% of the ER-negative subgroup. This feature was associated with decreased DFS both in the entire group (P=0.007) and in the ER-negative subgroup (P=0.03), but not in the tamoxifen-treated patients.Patients with ESR1 PvuII wt/wt genotype and at least one UGT2B15 wt allele had a worse DFS (P=0.03) and showed a trend towards decreased Os (P=0.08) in comparison to patients with ESR1 PvuII wt/vt or vt/vt genotype and UGT2B15 *2/*2 genotype.

Conclusions

ESR1 amplification can occur in ER-negative tumors and may carry poor prognosis. In the tamoxifen-treated subgroup, poor prognosis was related to the combined presence of ESR1 PvuII wt/wt and UGT2B15wt/wt or wt/*2 genotype.  相似文献   
27.
BACKGROUND: Clear cell renal cell carcinoma (CRCC) is the most common malignant tumor of the kidney, and the clinical outcome of CRCC is related with the metastatic potential of CRCC. A significant proportion of metastatic CRCC remains incurable. Recently, immunotherapy against specific targets such as programmed death 1 (PD1) has been adapted for fatal cases of CRCC. MATERIALS AND METHODS: In this study, we aimed to evaluate the potential of tumor-infiltrating PD1-positive lymphocytes or FoxP3-positive regulatory T cells (Tregs) as predictors of the metastatic potential or prognosis of CRCC and investigate possible correlations with Epstein-Barr virus (EBV) infection in 199 cases of CRCC. RESULTS: PD1 positivity, high Treg number, and EBV infection all predicted poor overall survival (OS) by univariate analysis. PD1 positivity and high Treg numbers were also significantly correlated with more distant metastatic relapse (DMR) and poor relapse-free survival (RFS) by univariate analysis. PD1 positivity and high Treg number were independent prognostic indicators for OS. In addition, PD1 positivity was an independent predictor of RFS and DMR. EBV infection was an independent predictor of OS of CRCC. CONCLUSION: This study demonstrates that intratumoral infiltration of PD1-positive or FoxP3-positive lymphocytes can be used as significant prognostic indicators of CRCC and PD1 positivity could be very helpful in the prediction of latent distant metastasis of CRCCs. Therefore, evaluation of the infiltration of PD-positive cells or Tregs in CRCC may be useful diagnostic tools for the selection of patients who could benefit from PD1- or Treg-based immunotherapy.  相似文献   
28.
BACKGROUND: Recently, deleted in breast cancer 1 (DBC1) has been suggested as a poor prognostic indicator of various human cancers and may possibly have a role as a coactivator of androgen receptor (AR). However, their roles in lymphoma are still unknown. MATERIALS AND METHODS: We investigated the effect of the expression of DBC1 and AR in diffuse large B cell lymphoma (DLBCL). Immunohistochemical expression of DBC1 and AR were evaluated in 101 DLBCL samples by tissue microarray. RESULTS: Positive expression of DBC1 and AR was seen in 73% and 70% of DLBCL, respectively. In total DLBCL patients, DBC1 and AR expression were significantly associated with high clinical stage, elevated serum lactate dehydrogenase levels, and high international prognostic index scores, and they predicted shorter overall survival (OS) and relapse-free survival (RFS) by univariate analysis. DBC1 expression was also an independent prognostic indicator by multivariate analysis (OS, P = .017; RFS, P = .004). Especially, both DBC1 and AR expression significantly correlated with shorter OS and RFS in non-germinal center B cell (non-GCB)-type DLBCL by univariate analysis. In multivariate analysis, DBC1 expression was an independent prognostic predictor for OS (P = .035) and AR expression significantly correlated with RFS (P = .005). CONCLUSION: We demonstrate that the expression of DBC1 and AR are significant prognostic indicators for DLBCL patients, especially for unfavorable non-GCB-type DLBCL.  相似文献   
29.
Prenatal exposure to alcohol has consistently been associated with adverse effects on neurodevelopment, which is collectively called fetal alcohol spectrum disorder (FASD). Increasing evidence suggest that prenatal exposure to alcohol increases the risk of developing attention deficit/hyperactivity disorder-like behavior in human. In this study, we investigated the behavioral effects of prenatal exposure to EtOH in offspring mice and rats focusing on hyperactivity and impulsivity. We also examined changes in dopamine transporter and MeCP2 expression, which may underlie as a key neurobiological and epigenetic determinant in FASD and hyperactive, inattentive and impulsive behaviors. Mouse or rat offspring born from dam exposed to alcohol during pregnancy (EtOH group) showed hyper locomotive activity, attention deficit and impulsivity. EtOH group also showed increased dopamine transporter and norepinephrine transporter level compared to control group in the prefrontal cortex and striatum. Prenatal exposure to EtOH also significantly decreased the expression of MeCP2 in both prefrontal cortex and striatum. These results suggest that prenatal exposure to EtOH induces hyperactive, inattentive and impulsive behaviors in rodent offspring that might be related to global epigenetic changes as well as aberration in catecholamine neurotransmitter transporter system.  相似文献   
30.
Based on the analysis of distribution of Middle-Late Jurassic foraminifers of the western Caucasus in each particular paleotectonic zone, the evolutionary dynamics of foraminiferal assemblages and their relationships are reconstructed. The evolutionary rates of Callovian-Tithonian foraminiferal assemblages in the paleotectonic zones are considered against a background of facies changes. Common and distinctive features in the change of foraminiferal communities and facies at different stages of foraminiferal evolution and the quality of environments for the development of foraminiferal associations are recognized.  相似文献   
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