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101.
In this contribution the results of a zoogeographical analysis, carried out on the 123 endemic leaf beetle species (Coleoptera: Chrysomelidae) occurring in Italy and its immediately adjacent regions, are reported. To assess the level of faunistic similarity among the different geographic regions studied, a cluster analysis was performed, based on the endemic component. This was done by calculating the Baroni Urbani & Buser’s similarity index (BUB). Finally, a parsimony analysis of endemicity (PAE) was used to identify the most important areas of endemism in Italy.  相似文献   
102.
The human prothymosin alpha (PTα) gene encodes a 12.5 kDa highly acidic nuclear protein that is widely expressed in mammalian tissues including the heart and importantly, is detectable also in blood serum. During apoptosis or necrosis, PTα changes its nuclear localization and is able to exert an important cytoprotective effect. Since the role of PTα in the heart has never been evaluated, the aim of the present study was to investigate the effects of PTα on cardiomyocytes during ischemic injury. Our data show that seven after myocardial infarction (MI), PTα expression levels are significantly increased both in blood serum and in cardiac tissue, and notably we observe that PTα translocates from the nuclei to cytoplasm and plasma membrane of cardiomyocytes following MI. Furthermore, in vitro experiments in cardiomyocytes, confirm that after 6 h of simulated ischemia (SI), PTα protein levels are upregulated compared to normoxic cells. Importantly, treatment of cardiomyocytes with a recombinant PTα (rPTα), during SI results in a significant decrease in the apoptotic response and in a robust increase in cell survival. Moreover, these effects are accompanied to a significant preservation of the activated levels of the anti-apoptotic serine-threonine kinase Akt. Consistent with our in vitro observation, rPTα-treated MI mice exhibit a strong reduction in infarct size at 24 h, compared to the MI control group and at the molecular level, PTα treatment induces activation of Akt. The present study provides for the first time the demonstration that PTα offers cardioprotection against ischemic injury by an Akt-dependent mechanism.  相似文献   
103.
Ghrelin is a metabolism-regulating hormone recently investigated for its role in cancer survival and progression. Controversially, ghrelin may act as either anti-apoptotic or pro-apoptotic factor in different cancer cells, suggesting that the effects are cell type dependent. Limited data are currently available on the effects exerted by ghrelin on intracellular proteolytic pathways in cancer. Both the lysosomal and the proteasomal systems are fundamental in cellular proliferation and apoptosis regulation. With the aim of exploring if the proteasome and autophagy may be possible targets of ghrelin in cancer, we exposed human colorectal adenocarcinoma cells to ghrelin. Preliminary in vitro fluorimetric assays evidenced for the first time a direct inhibition of 20S proteasomes by ghrelin, particularly evident for the trypsin-like activity. Moreover, 1 μM ghrelin induced apoptosis in colorectal adenocarcinoma cells by inhibiting the ubiquitin–proteasome system and by activating autophagy, with p53 having an “interactive” role.  相似文献   
104.
Quantitative information on population size, structure and dynamics are urgently needed for assessing species extinction risk and developing monitoring measures, especially for beetles belonging to the threatened guild of saproxylic organisms. Here freshly cut log piles (FCLP) were tested for the monitoring of the longhorn beetle Morimus asper (Sulzer, 1776) (Coleoptera: Cerambycidae). Novel mathematical models based on presence–absence or count data were compared with the most commonly used capture–recapture methods to investigate if less invasive and easier approaches may be suitable for large-scale monitoring of this species and other large saproxylic beetles. The use of FCLP as bait was reliable to detect the presence and abundance of M. asper, and capture events were not influenced by the phenomena of trap-happiness or trap-shyness. In order to obtain accurate presence–absence estimates of M. asper at a reasonable cost piles of at least 0.25 m3 are suggested. Models which take into account the abundance of the species without marking individuals were the best compromise between costs and accuracy of estimation. Therefore, a reliable assessment of the population size of M. asper, can be based on count data without marking individuals. Because FCLP attract adults of M. asper and other saproxylic beetles, they could act also as potential ecological traps if chipped and/or removed after the sampling season. Therefore, if FCLP are used in monitoring as a part of conservation programmes, the piles should be left until completely decayed.  相似文献   
105.
An industrial three-cascade-reactor plant treating 45 m3 d?1 of dairy wastewater (DW) was monitored for approx. one year to investigate the effect of variable daily influent loads. It removed more than 85% COD, NH4-N and non-ionic and anionic surfactants from DW within the loads 7–24, 0.4–2.3, 0.4–0.7 and 0.1–0.5 kg d?1, respectively; NH4-N removal, in particular, was almost quantitative. Although the degradation of the above parameters below the lower load thresholds declined to 78.7, 87.5, 50.2 and 64.7%, respectively, their residual concentrations met effluent discharge standards. The biomass settling properties, assessed as sludge volume index (SVI), were satisfactory (generally lower than 150 ml g?1) regardless of the organic load of the influent. The depletion of the pollutant load took mainly place in the first reactor albeit a significant contribution to the removal of the slowly degradable organic matter fraction was given by the two subsequent reactors.  相似文献   
106.
The Sorcerer II is the highly mediatized and spectacular Venter Institute's ship that circumnavigated the planet between 2003 and 2006 to collect and classify marine microbial genomes. We analyze Craig Venter's public communication activities and strategies especially focusing on the images of science and scientist he proposes: that of an eighteenth-century “savant” and nineteenth-century naturalist devoted to the exploration of new worlds, and that of the hacker, hero of informational capitalism. Emphasizing his independence from both academy and industry, but building strong alliances with both spheres and with the media, Craig Venter sails the oceans of the contemporary biotechnologies' market, interpreting a specific typology of the relationship between science and society, enterprises, universities.  相似文献   
107.

Background

No study has been carried out on the time trend in the prevalence of chronic bronchitis (CB) in recent years, despite its clinical and epidemiological relevance. We evaluated the trend in CB prevalence during the past decade among young Italian adults.

Methods

A screening questionnaire was mailed to general population samples of 20–44 year-old subjects in two cross-sectional surveys: the Italian Study on Asthma in Young Adults (ISAYA) (1998/2000; n = 18,873, 9 centres) and the screening stage of the Gene Environment Interactions in Respiratory Diseases (GEIRD) study (2007/2010; n = 10,494, 7 centres). CB was defined as having cough and phlegm on most days for a minimum of 3 months a year and for at least 2 successive years. The prevalence rates and the risk ratios (RRs) for the association between CB and each potential predictor were adjusted for gender, age, season of response, type of contact, cumulative response rate, and centre.

Results

CB prevalence was 12.5% (95% CI: 12.1-12.9%) in 1998/2000 and 12.6% (95% CI: 11.7-13.7%) in 2007/2010; it increased among never smokers (from 7.6 to 9.1%, p = 0.003), current light smokers (<15 pack-years; from 15.1 to 18.6%, p < 0.001), and unemployed/retired subjects (from 14.3 to 19.1%, p = 0.001). In this decade, the prevalence of current smoking decreased (from 33.6 to 26.9%, p < 0.001), whereas the prevalence of unemployment/premature retirement (from 5.3 to 6.0%, p = 0.005), asthma (from 5.0 to 6.2%, p = 0.003), and allergic rhinitis (from 19.5 to 24.5%, p < 0.001) increased. In both 1998/2000 and 2007/2010, the likelihood of having CB was significantly higher for women, current smokers, asthmatic patients, and subjects with allergic rhinitis. During this period, the strength of the association between CB and current heavy smoking (≥15 pack-years) decreased (RR: from 4.82 to 3.57, p = 0.018), whereas it increased for unemployment/premature retirement (from 1.11 to 1.53, p = 0.019); no change was observed for gender, asthma, and allergic rhinitis.

Conclusions

Despite the significant reduction in current smoking, CB prevalence did not vary among young Italian adults. The temporal pattern of CB prevalence can only be partly explained by the increase of unemployment/premature retirement, asthma and allergic rhinitis, and suggests that other factors could have played a role.  相似文献   
108.
Here, we developed a model system to evaluate the metabolic effects of oncogene(s) on the host microenvironment. A matched set of “normal” and oncogenically transformed epithelial cell lines were co-cultured with human fibroblasts, to determine the “bystander” effects of oncogenes on stromal cells. ROS production and glucose uptake were measured by FACS analysis. In addition, expression of a panel of metabolic protein biomarkers (Caveolin-1, MCT1, and MCT4) was analyzed in parallel. Interestingly, oncogene activation in cancer cells was sufficient to induce the metabolic reprogramming of cancer-associated fibroblasts toward glycolysis, via oxidative stress. Evidence for “metabolic symbiosis” between oxidative cancer cells and glycolytic fibroblasts was provided by MCT1/4 immunostaining. As such, oncogenes drive the establishment of a stromal-epithelial “lactate-shuttle”, to fuel the anabolic growth of cancer cells. Similar results were obtained with two divergent oncogenes (RAS and NFκB), indicating that ROS production and inflammation metabolically converge on the tumor stroma, driving glycolysis and upregulation of MCT4. These findings make stromal MCT4 an attractive target for new drug discovery, as MCT4 is a shared endpoint for the metabolic effects of many oncogenic stimuli. Thus, diverse oncogenes stimulate a common metabolic response in the tumor stroma. Conversely, we also show that fibroblasts protect cancer cells against oncogenic stress and senescence by reducing ROS production in tumor cells. Ras-transformed cells were also able to metabolically reprogram normal adjacent epithelia, indicating that cancer cells can use either fibroblasts or epithelial cells as “partners” for metabolic symbiosis. The antioxidant N-acetyl-cysteine (NAC) selectively halted mitochondrial biogenesis in Ras-transformed cells, but not in normal epithelia. NAC also blocked stromal induction of MCT4, indicating that NAC effectively functions as an “MCT4 inhibitor”. Taken together, our data provide new strategies for achieving more effective anticancer therapy. We conclude that oncogenes enable cancer cells to behave as selfish “metabolic parasites”, like foreign organisms (bacteria, fungi, viruses). Thus, we should consider treating cancer like an infectious disease, with new classes of metabolically targeted “antibiotics” to selectively starve cancer cells. Our results provide new support for the “seed and soil” hypothesis, which was first proposed in 1889 by the English surgeon, Stephen Paget.  相似文献   
109.
Triple-negative breast cancer (TNBC) represents an aggressive subtype, for which radiation and chemotherapy are the only options. Here we describe the identification of disulfiram, an FDA-approved drug used to treat alcoholism, as well as the related compound thiram, as the most potent growth inhibitors following high-throughput screens of 3185 compounds against multiple TNBC cell lines. The average IC50 for disulfiram was ~300 nM. Drug affinity responsive target stability (DARTS) analysis identified IQ motif-containing factors IQGAP1 and MYH9 as direct binding targets of disulfiram. Indeed, knockdown of these factors reduced, though did not completely abolish, cell growth. Combination treatment with 4 different drugs commonly used to treat TNBC revealed that disulfiram synergizes most effectively with doxorubicin to inhibit cell growth of TNBC cells. Disulfiram and doxorubicin cooperated to induce cell death as well as cellular senescence, and targeted the ESA+/CD24-/low/CD44+ cancer stem cell population. Our results suggest that disulfiram may be repurposed to treat TNBC in combination with doxorubicin.  相似文献   
110.

Background

Ultrasound is a valuable non-invasive tool used in obstetrics and gynecology to monitor the growth and well being of the human fetus. The laboratory mouse has recently emerged as an appropriate model for fetal and perinatal studies because morphogenetic processes in mice exhibit adequate homology to those in humans, and genetic manipulations are relatively simple to perform in mice. High-frequency ultrasound (HFUS) has recently become available for small animal preclinical imaging and can be used to study pregnancy and development in the mouse. The objective of the current study was to assess the main applications of HFUS in the evaluation of fetal growth and placental function and to better understand human congenital diseases.

Methodology/Principal Findings

On each gestational day, at least 5 dams were monitored with HFUS; a total of ∼200 embryos were examined. Because it is not possible to measure each variable for the entire duration of the pregnancy, the parameters were divided into three groups as a function of the time at which they were measured. Univariate analysis of the relationship between each measurement and the embryonic day was performed using Spearman’s rank correlation (Rs). Continuous linear regression was adopted for multivariate analysis of significant parameters. All statistical tests were two-sided, and a p value of 0.05 was considered statistically significant.

Conclusions/Significance

The study describes the main applications of HFUS to assess changes in phenotypic parameters in the developing CD1 mouse embryo and fetus during pregnancy and to evaluating physiological fetal and placental growth and the development of principal organs such as the heart, kidney, liver, brain and eyes in the embryonic mouse. A database of normal structural and functional parameters of mouse development will provide a useful tool for the better understanding of morphogenetic and cardiovascular anomalies in transgenic and mutant mouse models.  相似文献   
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