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51.
Andreoni V Zanchi R Cavalca L Corsini A Romagnoli C Canzi E 《Current microbiology》2012,65(2):212-218
The aim of this study was to characterize a facultative chemolithotrophic arsenite-oxidizing bacterium by evaluating the growth and the rate of arsenite oxidation and to investigate the genetic determinants for arsenic resistance and CO(2) fixation. The strain under study, Ancylobacter dichloromethanicus As3-1b, in a minimal medium containing 3 mM of arsenite as electron donor and 6 mM of CO(2)-bicarbonate as the C source, has a doubling time (t(d)) of 8.1 h. Growth and arsenite oxidation were significantly enhanced by the presence of 0.01 % yeast extract, decreasing the t(d) to 4.3 h. The strain carried arsenite oxidase (aioA) gene highly similar to those of previously reported arsenite-oxidizing Alpha-proteobacteria. The RuBisCO Type-I (cbbL) gene was amplified and sequenced too, underscoring the ability of As3-1b to carry out autotrophic As(III) oxidation. The results suggest that A. dichloromethanicus As3-1b can be a good candidate for the oxidation of arsenite in polluted waters or groundwaters. 相似文献
52.
Danubio ME Sanna E Rufo F Martorella D Vecchi E Coppa A 《Human biology; an international record of research》2012,84(2):153-167
This study analyzed the variations in space of 8 body dimensions and 11 measures of the head of 1,244 adult Yemenite males, collected in 1933/34 by Coon in Yemen and in Hadhramawt. The aim was to evaluate the presence of geographic microdifferentiation of the populations settled in the different regions of Yemen at the time. Coon sub-divided the sample into six geographical areas according to birthplace and ethnicity of the individuals: Tihamah, the Western Mountains, the Central Plateau, the South Coast, the Eastern Mountains, and Hadhramawt. The results of ANCOVA (age as covariate) show that the observed differences of all variables among the six groups were highly statistically significant. Tukey's post-hoc test reveals higher statistically significant differences among four main groups: (1) Tihamah; (2) the Western Mountains and Central Plateau; (3) the Eastern Mountains; and (4) the Southern Coast and Hadhramawt. Multiple discriminant analysis carried out using only the data of the 11 measures of the head, the more "genetically" determined variables, confirmed these differences. Indeed, the first canonical variate well separates the groups with the Tihamah, Southern Coast and Hadhramawt on the one side and the Eastern Mountains, Western Mountains and Central Plateau on the other. The second canonical variate separates the Tihamah, Western Mountains and Central Plateau from the Eastern Mountains, Southern Coast and Hadhramawt. In conclusion, the Yemenite population seems to be composed of three morphologically distinct groups and an Eastern Mountains group which is positioned between the group formed by the Southern Coast and Hadhramawt and the Western Mountains and Central Plateau group. The Tihamah is the most distant from all the other groups. These differences are probably due to the presence/absence of geographical and cultural barriers that have favored/blocked the gene flow over the years. Indeed, the entire coastal bell, through the centuries, has constituted one of the principal commercial routes between the East, Africa, and the eastern Mediterranean, while the high inland mountains have isolated the remaining communities. This data is also confirmed by genetic studies. Finally, the average height (162.6 cm) of the global Yemenite population, compared to data from the other six middle-eastern Arab countries and Egypt, was found to be 3-6 cm less. This characteristic will be further studied, analyzing variations in average height according to the different age classes in order to evaluate any possible secular changes. 相似文献
53.
E Villa R Vukotic C Cammà S Petta A Di Leo S Gitto E Turola A Karampatou L Losi V Bernabucci A Cenci S Tagliavini E Baraldi N De Maria R Gelmini E Bertolini M Rendina A Francavilla 《PloS one》2012,7(9):e44624
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54.
Slow, progressive rod degeneration followed by cone death leading to blindness is the pathological signature of all forms of human retinitis pigmentosa (RP). Therapeutic schemes based on intraocular delivery of neuroprotective agents prolong the lifetime of photoreceptors and have reached the stage of clinical trial. The success of these approaches depends upon optimization of chronic supply and appropriate combination of factors. Environmental enrichment (EE), a novel neuroprotective strategy based on enhanced motor, sensory and social stimulation, has already been shown to exert beneficial effects in animal models of various disorders of the CNS, including Alzheimer and Huntington disease. Here we report the results of prolonged exposure of rd10 mice, a mutant strain undergoing progressive photoreceptor degeneration mimicking human RP, to such an enriched environment from birth. By means of microscopy of retinal tissue, electrophysiological recordings, visual behaviour assessment and molecular analysis, we show that EE considerably preserves retinal morphology and physiology as well as visual perception over time in rd10 mutant mice. We find that protective effects of EE are accompanied by increased expression of retinal mRNAs for CNTF and mTOR, both factors known as instrumental to photoreceptor survival. Compared to other rescue approaches used in similar animal models, EE is highly effective, minimally invasive and results into a long-lasting retinal protection. These results open novel perspectives of research pointing to environmental strategies as useful tools to extend photoreceptor survival. 相似文献
55.
C Baranello M Mariani M Andreoli M Fanelli E Martinelli G Ferrandina G Scambia S Shahabi C Ferlini 《PloS one》2012,7(7):e40678
Stromal elements within a tumor interact with cancer cells to create a microenvironment that supports tumor growth and survival. Adrenomedullin (ADM) is an autocrine/paracrine factor produced by both stromal cells and cancer cells to create such a microenvironment. During differentiation of macrophages, ADM is produced in response to pro-inflammatory stimuli and hypoxia. In this study we investigated the role of ADM as a growth factor for ovarian cancer cells and as a modulator of macrophages. We also analyzed ADM expression levels in a retrospective clinical study using nanofluidic technology and assessment of ADM at the gene level in 220 ovarian cancer patients. To study the effects of ADM, ovarian cancer cell lines A2780, OVCAR-3, and HEY and their drug-resistant counterparts were used for proliferation assays, while monocytes from healthy donors were differentiated in vitro. ADM was a weak growth factor, as revealed by proliferation assays and cell cycle analysis. After culturing cancer cells under stressing conditions, such as serum starvation and/or hypoxia, ADM was found to be a survival factor in HEY but not in other cell lines. In macrophages, ADM showed activity on proliferation/differentiation, primarily in type 2 macrophages (M2). Unexpectedly, the clinical study revealed that high expression of ADM was linked to positive outcome and to cancer with low Ca125. In conclusion, although in vitro ADM was a potential factor in biological aggressiveness, this possibility was not confirmed in patients. Therefore, use of an ADM antagonist would be inappropriate in managing ovarian cancer patients. 相似文献
56.
Rutella S Iudicone P Bonanno G Fioravanti D Procoli A Lavorino C Foddai ML Lorusso D Martinelli E Vacca M Ipsevich F Nuti M Scambia G Pierelli L 《Cytotherapy》2012,14(7):841-850
Background aimsWe have recently shown that thymoglobulin (TG) efficiently expands cytokine-induced killer (CIK) cells in combination with interferon (IFN)-γ and interleukin (IL)-2 (ITG2 protocol). It is presently unknown whether the infusion of autologous immune effector cells generated by TG, IFN-γ and IL-2 is feasible and safeMethodsFive patients with advanced and/or refractory solid tumors were enrolled in the present phase I/II study. Peripheral blood mononuclear cells (PBMC) collected by leukapheresis were stimulated under good manufacturing practice (GMP)-conditions with IFN-γ, followed by TG and IL-2. After 2–3 weeks in culture, a median of 4.65 × 106 immune effector cells per kilogram of recipient's body weight was obtained and infused intravenously. The median time from enrollment into the study to infusion of the expanded CIK cells was 30 daysResultsITG2 efficiently expanded immune effector cells that comprised both conventional natural killer (NK) cells and CD3+ CD16+ CD56+ CIK cells. One patient with advanced melanoma died because of disease progression before the infusion of CIK cells. The target dose of at least 2.5 × 106 CIK cells/kg of recipient's body weight was reached in four out of five evaluable patients. CIK cells were administered intravenously without any measurable toxicity. In vitro, CIK cells exerted lytic activity against cervical cancer cells. The median survival was 4.5 months (range 1–13) from the first infusion of CIK cells.ConclusionsThis study has highlighted the feasibility and safety of the administration of CIK cells generated with the ITG2 protocol. Whether CIK cells can help control disease burden in patients with advanced malignancies will be determined in future clinical trials. 相似文献
57.
Background
Gene set analysis is moving towards considering pathway topology as a crucial feature. Pathway elements are complex entities such as protein complexes, gene family members and chemical compounds. The conversion of pathway topology to a gene/protein networks (where nodes are a simple element like a gene/protein) is a critical and challenging task that enables topology-based gene set analyses. 相似文献58.
Jenny Anne Glikman Jerry J. Vaske Alistair J. Bath Paolo Ciucci Luigi Boitani 《European Journal of Wildlife Research》2012,58(1):295-302
This article examines the combined influence of cognitions (i.e., impact beliefs) and affect (i.e., feelings) on normative
beliefs (i.e., support for management options) about wolves and brown bears. Data were obtained from stratified random face-to-face
interviews (n = 1,611). The survey was conducted in the Abruzzo Lazio and Molise National Park (central Italy), where people have a long
history of coexistence with large carnivores. Knowledge was hypothesized to moderate the relationships of beliefs and feelings
on support for management actions. Path analyses supported the role of affect in mediating perceived impact beliefs and support
for the protection of large carnivores. Knowledge moderated these relationships in the case of wolves but not brown bears.
Residents of the national park had more knowledge about bears than wolves, which might partly explain both the stronger effect
that knowledge had on the affective component and its lack of a moderating effect on the bear model. Overall, our findings
show the positive attitude of residents toward large carnivores and support the idea of affect being more important than cognition
in predicting normative beliefs. 相似文献
59.
Giovanna Di Domenico Elisabetta Tosoni Luigi Boitani Paolo Ciucci 《Mammalian Biology》2012,77(3):190-195
Bear food habits are often quantified using scat analysis, mainly due to its non-invasiveness and because samples are relatively easy to collect. However, lab processing time can be daunting and may end up competing with other field activities. Sub-sampling a bear scat to analyze its contents may reduce the lab processing time, but the number of subsamples per scat is usually chosen arbitrarily. We investigated the effect of the number of subsamples per bear scat on the estimatation of the diet composition of the Apennine brown bear in the Abruzzo Lazio and Molise National Park. Based on a sample of 328 bear scats collected in 2006, and from 5 to 1 subsamples (10 ml) per scat, dietary analysis showed qualitative and quantitative stability at a decreasing number of subsamples, and only food items of negligible importance were occasionally missed using 1–2 subsamples per scat. We concluded that 2 subsamples can be used without significant loss in accuracy, corresponding to a 60% reduction in lab time, and to more than 50 days of lab work for one operator to process our entire bear scat sample. By assessing the effect of sub-sampling a bear scat for dietary analysis, we also present preliminary data on the seasonal food habits of the Apennine brown bear population. 相似文献
60.