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131.
132.

Introduction

Chronic hepatitis C is the main cause of death in patients with end-stage liver disease. Prognosis depends on the increase of fibrosis, whose progression is twice as rapid in men as in women. Aim of the study was to evaluate the effects of reproductive stage on fibrosis severity in women and to compare these findings with age-matched men.

Materials and Methods

A retrospective study of 710 consecutive patients with biopsy-proven chronic hepatitis C was conducted, using data from a clinical database of two tertiary Italian care centers. Four age-matched groups of men served as controls. Data about demographics, biochemistry, liver biopsy and ultrasonography were analyzed. Contributing factors were assessed by multivariate logistic regression analysis.

Results

Liver fibrosis was more advanced in the early menopausal than in the fully reproductive (P<0.0001) or premenopausal (P = 0.042) group. Late menopausal women had higher liver fibrosis compared with the other groups (fully reproductive, P<0.0001; premenopausal, P = <0.0001; early menopausal, P = 0.052). Multivariate analyses showed that male sex was independently associated with more severe fibrosis in the groups corresponding to premenopausal (P = 0.048) and early menopausal (P = 0.004) but not late menopausal pairs. In women, estradiol/testosterone ratio decreased markedly in early (vs. reproductive age: P = 0.002 and vs. premenopausal: P<0.0001) and late menopause (vs. reproductive age: P = 0.001; vs. premenopausal: P<0.0001). In men age-matched with menopausal women, estradiol/testosterone ratio instead increased (reproductive age group vs. early: P = 0.002 and vs. late M: P = 0.001).

Conclusions

The severity of fibrosis in women worsens in parallel with increasing estrogen deprivation and estradiol/testosterone ratio decrease. Our data provide evidence why fibrosis progression is discontinuous in women and more linear and severe in men, in whom aging-associated estradiol/testosterone ratio increase occurs too late to noticeably influence the inflammatory process leading to fibrosis.  相似文献   
133.
Cell lines are key tools in cancer research allowing the generation of neoplasias in animal models resembling the initial tumours able to mimic the original neoplasias closely in vivo. Canine lymphoma is the major hematopoietic malignancy in dogs and considered as a valuable spontaneous large animal model for human Non-Hodgkin's Lymphoma (NHL). Herein we describe the establishment and characterisation of an in vivo model using the canine B-cell lymphoma cell line CLBL-1 analysing the stability of the induced tumours and the ability to resemble the original material. CLBL-1 was injected into Rag2(-/-)γ(c) (-/-) mice. The generated tumor material was analysed by immunophenotyping and histopathology and used to establish the cell line CLBL-1M. Both cell lines were karyotyped for detection of chromosomal aberrations. Additionally, CLBL-1 was stimulated with IL-2 and DSP30 as described for primary canine B-cell lymphomas and NHL to examine the stimulatory effect on cell proliferation. CLBL-1 in vivo application resulted in lymphoma-like disease and tumor formation. Immunophenotypic analysis of tumorous material showed expression of CD45(+), MHCII(+), CD11a(+) and CD79αcy(+). PARR analysis showed positivity for IgH indicating a monoclonal character. These cytogenetic, molecular, immunophenotypical and histological characterisations of the in vivo model reveal that the induced tumours and thereof generated cell line resemble closely the original material. After DSP30 and IL-2 stimulation, CLBL-1 showed to respond in the same way as primary material. The herein described CLBL-1 in vivo model provides a highly stable tool for B-cell lymphoma research in veterinary and human medicine allowing various further in vivo studies.  相似文献   
134.
We have previously shown that inhibition of transforming growth factor-β (TGF-β) signaling attenuates hypoxia-induced inhibition of alveolar development and abnormal pulmonary vascular remodeling in the newborn mice and that endothelin-A receptor (ETAR) antagonists prevent and reverse the vascular remodeling. The current study tested the hypothesis that inhibition of TGF-β signaling attenuates endothelin-1 (ET-1) expression and thereby reduces effects of hypoxia on the newborn lung. C57BL/6 mice were exposed from birth to 2 wk of age to either air or hypoxia (12% O(2)) while being given either BQ610 (ETAR antagonist), BQ788 (ETBR antagonist), 1D11 (TGF-β neutralizing antibody), or vehicle. Lung function and development and TGF-β and ET-1 synthesis were assessed. Hypoxia inhibited alveolar development, decreased lung compliance, and increased lung resistance. These effects were associated with increased TGF-β synthesis and signaling and increased ET-1 synthesis. BQ610 (but not BQ788) improved lung function, without altering alveolar development or increased TGF-β signaling in hypoxia-exposed animals. Inhibition of TGF-β signaling reduced ET-1 in vivo, which was confirmed in vitro in mouse pulmonary endothelial, fibroblast, and epithelial cells. ETAR blockade improves function but not development of the hypoxic newborn lung. Reduction of ET-1 via inhibition of TGF-β signaling indicates that TGF-β is upstream of ET-1 during hypoxia-induced signaling in the newborn lung.  相似文献   
135.

Introduction

Breast cancer is a common disease with distinct tumor subtypes phenotypically characterized by ER and HER2/neu receptor status. MiRNAs play regulatory roles in tumor initiation and progression, and altered miRNA expression has been demonstrated in a variety of cancer states presenting the potential for exploitation as cancer biomarkers. Blood provides an excellent medium for biomarker discovery. This study investigated systemic miRNAs differentially expressed in Luminal A-like (ER+PR+HER2/neu-) breast cancer and their effectiveness as oncologic biomarkers in the clinical setting.

Methods

Blood samples were prospectively collected from patients with Luminal A-like breast cancer (n = 54) and controls (n = 56). RNA was extracted, reverse transcribed and subjected to microarray analysis (n = 10 Luminal A-like; n = 10 Control). Differentially expressed miRNAs were identified by artificial neural network (ANN) data-mining algorithms. Expression of specific miRNAs was validated by RQ-PCR (n = 44 Luminal A; n = 46 Control) and potential relationships between circulating miRNA levels and clinicopathological features of breast cancer were investigated.

Results

Microarray analysis identified 76 differentially expressed miRNAs. ANN revealed 10 miRNAs for further analysis (miR-19b, miR-29a, miR-93, miR-181a, miR-182, miR-223, miR-301a, miR-423-5p, miR-486-5 and miR-652). The biomarker potential of 4 miRNAs (miR-29a, miR-181a, miR-223 and miR-652) was confirmed by RQ-PCR, with significantly reduced expression in blood of women with Luminal A-like breast tumors compared to healthy controls (p = 0.001, 0.004, 0.009 and 0.004 respectively). Binary logistic regression confirmed that combination of 3 of these miRNAs (miR-29a, miR-181a and miR-652) could reliably differentiate between cancers and controls with an AUC of 0.80.

Conclusion

This study provides insight into the underlying molecular portrait of Luminal A-like breast cancer subtype. From an initial 76 miRNAs, 4 were validated with altered expression in the blood of women with Luminal A-like breast cancer. The expression profiles of these 3 miRNAs, in combination with mammography, has potential to facilitate accurate subtype-specific breast tumor detection.  相似文献   
136.
Animals often respond fearfully when encountering eyes or eye-like shapes. Although gaze aversion has been documented in mammals when avoiding group-member conflict, the importance of eye coloration during interactions between conspecifics has yet to be examined in non-primate species. Jackdaws (Corvus monedula) have near-white irides, which are conspicuous against their dark feathers and visible when seen from outside the cavities where they nest. Because jackdaws compete for nest sites, their conspicuous eyes may act as a warning signal to indicate that a nest is occupied and deter intrusions by conspecifics. We tested whether jackdaws’ pale irides serve as a deterrent to prospecting conspecifics by comparing prospectors’ behaviour towards nest-boxes displaying images with bright eyes (BEs) only, a jackdaw face with natural BEs, or a jackdaw face with dark eyes. The jackdaw face with BEs was most effective in deterring birds from making contact with nest-boxes, whereas both BE conditions reduced the amount of time jackdaws spent in proximity to the image. We suggest BEs in jackdaws may function to prevent conspecific competitors from approaching occupied nest sites.  相似文献   
137.
138.
The aim of the study was to obtain the highest number of multipotent adipose-derived mesenchymal stem cells (ADMSCs) by using culture conditions which favour cell expansion without loss of mesenchymal stem cells (MSC)-like properties. Based on the assumption that stem cells reside in niches characterized by hypoxic condition, we investigated if the low oxygen tension may improve the proliferation and stemness of ADMSCs. Intact adipose tissue was resected from eight subjects, and the stromal vascular fraction was obtained by using type II collagenase. The heterogeneity of cellular lineages was confirmed by immunophenotypic analysis that showed the presence of leukocytes (CD45+), endothelial cells (CD34+), and pericytes (CD140+). The immunophenotype of confluent ADMSCs was similar to that of bone marrow-derived MSCs, except for the expression of CD34, which was variable (donor-dependent) and inversely correlated to the CD36 expression. ADMSCs showed a high clonal efficiency (94.5 ± 1 %) and were able to generate osteoblastic, chondrocytic and adipocytic lineages. ADMSCs were cultured under normoxic (21 % O2) and hypoxic (1 % O2) conditions, and we found that hypoxia significantly favoured ADMSC proliferation and preserved the expression of stemness genes, i.e. Nanog and Sox2. Since hypoxia reflects the microenvironment in which ADMSCs must proliferate and differentiate, the culture in hypoxic condition allows to better understand the biology of these cells and their regenerative potential. Low oxygen concentrations promote cell proliferation and stemness, thus enriching the pool of cells potentially able to differentiate into multi-lineages, and extending the possibility of a long-term expansion.  相似文献   
139.

Background

Screening for type 2 diabetes (T2DM) and individuals at risk of diabetes has been advocated, yet information on the response rate and diagnostic yield of different screening strategies are lacking.

Methods

Studies (from 1998 to March/2015) were identified through Medline, Embase and the Cochrane library and included if they used oral glucose tolerance test (OGTT) and WHO-1998 diagnostic criteria for screening in a community setting. Studies were one-step strategy if participants were invited directly for OGTT and two, three/four step if participants were screened at one or more levels prior to invitation to OGTT. The response rate and diagnostic yield were pooled using Bayesian random-effect meta-analyses.

Findings

47 studies (422754 participants); 29 one-step, 11 two-step and seven three/four-step were identified. Pooled response rate (95% Credible Interval) for invitation to OGTT was 65.5% (53.7, 75.6), 63.1% (44.0, 76.8), and 85.4% (76.4, 93.3) in one, two and three/four-step studies respectively. T2DM yield was 6.6% (5.3, 7.8), 13.1% (4.3, 30.9) and 27.9% (8.6, 66.3) for one, two and three/four-step strategies respectively. The number needed to invite to the OGTT to detect one case of T2DM was 15, 7.6 and 3.6 in one, two, and three/four-step strategies. In two step strategies, there was no difference between the response or yield rates whether the first step was blood test or risk-score. There was evidence of substantial heterogeneity in rates across study populations but this was not explained by the method of invitation, study location (rural versus urban) and developmental index of the country in which the study was performed.

Conclusions

Irrespective of the invitation method, developmental status of the countries and or rural/urban location, using a multi-step strategy increases the initial response rate to the invitation to screening for diabetes and reduces the number needed to have the final diagnostic test (OGTT in this study) for a definite diagnosis.  相似文献   
140.
Mono‐ and bis‐alkaloid chiral auxiliaries with anthraquinone or phenanthryl cores were probed as chiral solvating agents (CSAs) for the enantiodiscrimination of chiral cyclic hemiesters. The dimeric anthraquinone derivative and the monomeric phenanthryl one showed remarkable efficiency in the nuclear magnetic resonance (NMR) differentiation of enantiomeric mixtures of hemiesters. An anthraquinone analogous with a single alkaloid unit was remarkably less effective. The conformational prevalence of the chiral auxiliaries were ascertained by NMR. Chirality 27:693–699, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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