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101.

Introduction

Although cetuximab and panitumumab show an increased efficacy for patients with KRAS-NRAS-BRAF and PI3KCA wild-type metastatic colorectal cancer, primary resistance occurs in a relevant subset of molecularly enriched populations.

Patients and Methods

We evaluated the outcome of 68 patients with advanced colorectal cancer and RAS, BRAF and PI3KCA status according to ALK gene status (disomic vs. gain of ALK gene copy number – defined as mean of 3 to 5 fusion signals in ≥10% of cells). All consecutive patients received cetuximab and irinotecan or panitumumab alone for chemorefractory disease.

Results

No ALK translocations or amplifications were detected. ALK gene copy number gain was found in 25 (37%) tumors. Response rate was significantly higher in patients with disomic ALK as compared to those with gain of gene copy number (70% vs. 32%; p = 0.0048). Similarly, progression-free survival was significantly different when comparing the two groups (6.7 vs. 5.3 months; p = 0.045). A trend was observed also for overall survival (18.5 vs. 15.6 months; p = 0.885).

Conclusion

Gain of ALK gene copy number might represent a negative prognostic factor in mCRC and may have a role in resistance to anti-EGFR therapy.  相似文献   
102.
Placebo analgesia is mediated by both opioid and nonopioid mechanisms, but so far nothing is known about the nonopioid component. Here we show that the specific CB1 cannabinoid receptor antagonist 5-(4-chlorophenyl)-1-(2,4-dichloro-phenyl)-4-methyl-N-(piperidin-1-yl)-1H-pyrazole-3-carboxamide (rimonabant or SR141716) blocks nonopioid placebo analgesic responses but has no effect on opioid placebo responses. These findings suggest that the endocannabinoid system has a pivotal role in placebo analgesia in some circumstances when the opioid system is not involved.  相似文献   
103.

Introduction

Media sensationalism on the H1N1 outbreak may have influenced decisional processes and clinical diagnosis.

Case Presentation

We report two cases of patients who presented in 2009 with coexisting H1N1 virus and Legionella infections: a 69-year-old Caucasian man and a 71-year-old Caucasian woman. In our cases all the signs and symptoms, including vomiting, progressive respiratory disease leading to respiratory failure, refractory hypoxemia, leukopenia, lymphopenia, thrombocytopenia, and elevated levels of creatine kinase and hepatic aminotransferases, were consistent with critical illness due to 2009 H1N1 virus infection. Other infectious disorders may mimic H1N1 viral infection especially Legionnaires' disease. Because the swine flu H1N1 pandemic occurred in Autumn in Italy, Legionnaires disease was to be highly suspected since the peak incidence usually occurs in early fall. We do think that our immediate suspicion of Legionella infection based on clinical history and X-ray abnormalities was fundamental for a successful resolution.

Conclusion

Our two case reports suggest that patients with H1N1 should be screened for Legionella, which is not currently common practice. This is particularly important since the signs and symptoms of both infections are similar.
  相似文献   
104.
Sorafenib was shown in clinical trial to enhance survival in hepatocellular carcinoma (HCC) patients, but with minimal tumor shrinkage. To correlate several indices of HCC growth at various drug concentrations, HCC cells were grown in various low concentrations of two multikinase inhibitors, Regorafenib (Stivarga) and Sorafenib (Nexavar) and their effects were examined on alpha‐fetoprotein (AFP), cell growth, migration, and invasion. In two AFP positive human HCC cell lines, AFP was inhibited at 0.1–1 µM drug concentrations. Cell migration and invasion were also inhibited at similar low drug concentrations. However, 10‐fold higher drug concentrations were required to inhibit cell growth in both AFP positive and negative cells. To investigate this concentration discrepancy of effects, cells were then grown for prolonged times and sub‐cultured in low drug concentrations and then their growth was re‐tested. The growth in these drug‐exposed cells was found to be slower than cells without prior drug exposure and they were also more sensitive to subsequent drug challenge. Evidence was also found for changes in cell signaling pathways in these slow‐growth cells. Low multikinase inhibitor concentrations thus modulate several aspects of HCC cell biology. J. Cell. Physiol. 228: 1344–1350, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
105.

Background

Determining genetic risk is a fundamental prerequisite for the implementation of primary prevention trials for type 1 diabetes (T1D). The aim of this study was to assess the risk conferred by HLA-DRB1, INS-VNTR and PTPN22 single genes on the onset of T1D and the joint risk conferred by all these three susceptibility loci using the Bayesian Network (BN) approach in both population-based case-control and family clustering data sets.

Methodology/Principal Findings

A case-control French cohort, consisting of 868 T1D patients and 73 French control subjects, a French family data set consisting of 1694 T1D patients and 2340 controls were analysed. We studied both samples separately applying the BN probabilistic approach, that is a graphical model that encodes probabilistic relationships among variables of interest. As expected HLA-DRB1 is the most relevant susceptibility gene. We proved that INS and PTPN22 genes marginally influence T1D risk in all risk HLA-DRB1 genotype categories. The absolute risk conferred by carrying simultaneously high, moderate or low risk HLA-DRB1 genotypes together with at risk INS and PTPN22 genotypes, was 11.5%, 1.7% and 0.1% in the case-control sample and 19.8%, 6.6% and 2.2% in the family cohort, respectively.

Conclusions/Significance

This work represents, to the best of our knowledge, the first study based on both case-control and family data sets, showing the joint effect of HLA, INS and PTPN22 in a T1D Caucasian population with a wide range of age at T1D onset, adding new insights to previous findings regarding data sets consisting of patients and controls <15 years at onset.  相似文献   
106.
Salmonids inhabiting Mediterranean rivers are of particular concern for biodiversity conservation, as they are threatened by various stressors, including habitat alterations, overfishing, climate change, and introgressive hybridization with alien species. In the Tiber River basin (Central Italy), genetic introgression phenomena of the native Salmo cettii with the non‐native Salmo trutta hinder the separate analysis of the two species, which are both included in the S. trutta complex. Little is known about the factors currently limiting the trout populations in this area, particularly with respect to climate change. With the intention of filling this gap, the aims of the current study were to (a) quantify changes in the climate and (b) analyze the distribution, status, and ecology of trout populations, in the context of changing abiotic conditions over the last decades. Fish stock assessments were carried out by electrofishing during three census periods (1998–2004, 2005–2011, and 2012–2018) at 129 sites. The trend over time of meteorological parameters provided evidence for increased air temperature and decreased rainfall. Multivariate analysis of trout densities and environmental data highlighted the close direct correlation of trout abundance with water quality, altitude, and current speed. Climate‐induced effects observed over time in the sites where trout were sampled have not yet led to local extinctions or distribution shifts, indicating a marked resilience of trout, probably due to the buffering effect of intrinsic population dynamics. Decreasing body conditions over time and unbalanced age structures support the hypothesis that variations in hydraulic regime and water temperature could overcome these compensatory effects, which may lead to a severe decline in trout populations in the near future. In a climate change context, habitat availability plays a key role in the distribution of cold‐water species, which often do not have the possibility to move upstream to reach their thermal optimum because of water scarcity in the upper river stretches.  相似文献   
107.
The aim of this work was to evaluate the suitability of four strains of Saccharomyces cerevisiae endowed with in vitro β-glucosidase activity to improve the Sangiovese wine aroma profiles. In particular the effects of the strains on fermentation kinetics, wine sugar and acid concentrations, volatile molecule profiles and colour parameters were evaluated. Moreover their effects on anthocyanins, anthocyanidins and poliphenols were evaluated. These four strains of S. cerevisiae were tested in comparison with one commercial strain and with a spontaneous fermentation in the presence and in the absence of paraffin oil. The results showed that the four wild strains had high fermentation rates and an efficient conversion of grape sugars to alcohol. However, each strain imparted specific features to the wine. AS11 and AS15 gave rise to wine having low volatile acidity values associated to high levels of linalool and nerolidol. They provoked decrease of anthocyanins accompanied by the increase of some anthocyanidins. S. cerevisiae BV12 and BV14 showed the best performances producing wines with the lowest residual sugar contents and volatile acidity values, high levels of nerolidol and citronellol without detrimental effects on wine colour.  相似文献   
108.
In this study, we analysed the patterns of variation of the European treefrog's advertisement call at four levels of organization: within individuals, within populations, among populations of the same species, and among different species of the same clade. At the within-individual level, call acoustic properties are distinguished into static and dynamic properties. At the within-population level, two sources of call variation were analysed: temperature and body size. Temperature affects both temporal and spectral properties of the call. Body size mostly affects spectral properties. At the between-population level, calls do not show significant differences with respect to temporal properties, but they do differ in two spectral (and stereotyped) properties: the fundamental frequency and the difference in amplitude between dominant and fundamental frequencies. Finally, at the between-species level, call differences are much more conspicuous: they involve both spectral and temporal and both static and dynamic properties. At all four levels, body size is associated with call variation, explaining 11% of the differences among populations of the same species and 73% of the differences among species of the same clade. On the basis of these results, we hypothesize that patterns of variation of call acoustic properties, their constraints, and their biological functions are intrinsically associated. We discuss the role that such an association might play in the evolution of acoustic signals.  相似文献   
109.
The antioxidant enzyme CuZn superoxide dismutase (SOD1) is secreted by many cell lines. However, it is not clear whether SOD1 secretion is only constitutive or can be regulated in an activity-dependent fashion. Using rat pituitary GH(3) cells that express voltage-dependent calcium channels and are subjected to Ca(2+) oscillations, we found that treatment with high K(+)-induced SOD1 release that was significantly higher than the constitutive secretion. Evoked SOD1 release was correlated with depolarization-dependent calcium influx and was virtually abolished by removal of extracellular calcium with EGTA or by pre-incubation of GH(3) cells with Botulinum toxin A that cleaves the SNARE protein SNAP-25. Immunofluorescence experiments performed in GH(3) cells and rat brain synaptosomes showed that K(+)-depolarization induced a marked depletion of intracellular SOD1 immunoreactivity, an effect that was again abolished in the absence of extracellular calcium or after treatment with Botulinum toxin A. Subcellular fractionation analysis showed that SOD1 was present in large dense core vesicles. These data clearly show that, in addition to the constitutive SOD1 secretion, depolarization induces an additional rapid calcium-dependent SOD1 release in GH(3) cells and in rat brain synaptosomes. This likely occurs through exocytosis from SOD1-containing vesicles operated by the SNARE complex.  相似文献   
110.
Pre-Lamin A processing is linked to heterochromatin organization   总被引:1,自引:0,他引:1  
Pre-lamin A undergoes subsequent steps of post-translational modification at its C-terminus, including farnesylation, methylation, and cleavage by ZMPSTE24 metalloprotease. Here, we show that accumulation of different intermediates of pre-lamin A processing in nuclei, induced by expression of mutated pre-lamin A, differentially affected chromatin organization in human fibroblasts. Unprocessed (non-farnesylated) pre-lamin A accumulated in intranuclear foci, caused the redistribution of LAP2alpha and of the heterochromatin markers HP1alpha and trimethyl-K9-histone 3, and triggered heterochromatin localization in the nuclear interior. In contrast, the farnesylated and carboxymethylated lamin A precursor accumulated at the nuclear periphery and caused loss of heterochromatin markers and Lap2alpha in enlarged nuclei. Interestingly, pre-lamin A bound both HP1alpha and LAP2alpha in vivo, but the farnesylated form showed reduced affinity for HP1alpha. Our data show a link between pre-lamin A processing and heterochromatin remodeling and have major implications for understanding molecular mechanisms of human diseases linked to mutations in lamins.  相似文献   
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