589 research outputs found
WO3-decorated ZnO nanostructures for light-activated applications
In the present work, a two-step vapor-phase route was implemented for the tailored design of ZnO\u2013WO3
nanoheterostructures supported on fluorine-doped tin oxide (FTO) substrates. Under optimized conditions,
the sequential use of chemical vapor deposition (CVD) and radio frequency (RF)-sputtering for the deposition
of zinc and tungsten oxides respectively, resulted in the growth of calyx-like ZnO nanostructures uniformly
decorated by a conformal dispersion of low-sized WO3 nanoparticles. The target materials were
characterized by means of a multi-technique approach, with particular regard to their structural, compositional, morphological and optical properties. Finally, their photocatalytic performances were preliminarily tested in the abatement of NOX gases (NO and NO2). Due to the unique porous morphology of the ZnO nanodeposit and the high density of ZnO\u2013WO3 heterojunctions, WO3-decorated ZnO revealed appealing De-NOX characteristics in terms of both degradation efficiency and selectivity. Such features, along with the photoinduced superhydrophilicity and self-cleaning properties of the present nanomaterials, candidate them as promising functional platforms for applications in smart windows and building materials for environmental remediation
The versatile nature of miR-9/9* in human cancer
miR-9 and miR-9* (miR-9/9*) were first shown to be expressed in the nervous system and to function as versatile regulators of neurogenesis. The variable expression levels of miR-9/9* in human cancer prompted researchers to investigate whether these small RNAs may also have an important role in the deregulation of physiological and biochemical networks in human disease. In this review, we present a comprehensive overview of the involvement of miR-9/9* in various human malignancies focusing on their opposing roles in supporting or suppressing tumor development and metastasis. Importantly, it is shown that the capacity of miR-9/9* to impact tumor formation is independent from their influence on the metastatic potential of tumor cells. Moreover, data suggest that miR-9/9* may increase malignancy of one cancer cell population at the expense of another. The functional versatility of miR-9/9* emphasizes the complexity of studying miRNA function and the importance to perform functional studies of both miRNA strands in a relevant cellular context. The possible application of miR-9/9* as targets for miRNA-based therapies is discussed, emphasizing the need to obtain a better understanding of the functional properties of these miRNAs and to develop safe delivery methods to target specific cell populations
Dementia incidence, APOE genotype, and risk factors for cognitive decline in Aboriginal Australians
Background and Objectives Aboriginal Australians are disproportionately affected by dementia, with incidence in remote populations approximately double that of non-Indigenous populations. This study aimed to identify dementia incidence and risk factors in Aboriginal Australians residing in urban areas, which are currently unknown. Methods A population-based cohort of Aboriginal Australians ≥60 years of age was assessed at baseline and 6-year follow-up. Life-course risk factors (baseline) were examined for incident dementia or mild cognitive impairment (MCI) through logistic regression analyses; adjustments were made for age. APOE genotyping was available for 86 people. Results Data were included from 155 participants 60 to 86 years of age (mean 65.70 years, SD 5.65 years; 59 male). There were 16 incident dementia cases (age-standardized rate 35.97/1,000 person-years, 95% confidence interval [CI] 18.34–53.60) and 36 combined incident MCI and dementia cases. Older age (odds ratio [OR] 2.29, 95% CI 1.42–3.70), male sex (OR 4.14, 95% CI 1.60–10.77), unskilled work history (OR 5.09, 95% CI 1.95–13.26), polypharmacy (OR 3.11, 95% CI 1.17–8.28), and past smoking (OR 0.24, 95% CI 0.08–0.75) were associated with incident MCI/dementia in the final model. APOE e4 allele frequency was 24%; heterozygous or homozygous e4 was associated with incident MCI/dementia (bivariate OR 3.96, 95% CI 1.25–12.50). Discussion These findings provide evidence for higher dementia incidence in Aboriginal Australians from urban areas, where the majority of Aboriginal people reside. This study also sheds light on sociodemographic, health, and genetic factors associated with incident MCI/dementia at older ages in this population, which is critical for targeted prevention strategies
Surface Functionalization of Grown-on-Tip ZnO Nanopyramids: From Fabrication to Light-Triggered Applications
We report on a combined
chemical vapor deposition (CVD)/radio frequency
(RF) sputtering synthetic strategy for the controlled surface modification
of ZnO nanostructures by Ti-containing species. Specifically, the
proposed approach consists in the CVD of grown-on-tip ZnO nanopyramids,
followed by titanium RF sputtering under mild conditions. The results
obtained by a thorough characterization demonstrate the successful
ZnO surface functionalization with dispersed Ti-containing species
in low amounts. This phenomenon, in turn, yields a remarkable enhancement
of photoactivated superhydrophilic behavior, self-cleaning ability,
and photocatalytic performances in comparison to bare ZnO. The reasons
accounting for such an improvement are unravelled by a multitechnique
analysis, elucidating the interplay between material chemico-physical
properties and the corresponding functional behavior. Overall, the
proposed strategy stands as an amenable tool for the mastering of
semiconductor-based functional nanoarchitectures through <i>ad
hoc</i> engineering of the system surface
MicroRNAs: the primary cause or a determinant of progression in leukemia?
available in PMC 2011 October 10.Leukemia is a complex disease with many different types and subtypes caused by a huge
diversity of genetic and epigenetic aberrations. Until recently, alterations of protein-coding
genes were thought to be the sole cause of tumorigenesis. With the recent discovery of
multiple types of non-coding RNAs, it has become evident that mutations in these also
contribute to the development of cancer. Among the non-coding RNAs, microRNAs play a
crucial role in cancer owing to their involvement in fundamental processes such as
apoptosis, differentiation and proliferation.
MicroRNAs are small noncoding RNAs (approximately 19–25 nucleotides in length) that
bind to and downregulate multiple mRNA targets; in mammals, the production of over a
third of all proteins is regulated by microRNAs [3]. Several studies demonstrated that
microRNAs are involved in leukemia progression but their role as the primary cause or a
determinant of progression in leukemia has been unclear. Some have been identified as
oncogenes or tumor suppressor genes, which suggests that they are playing a central role in
tumorigenesis, while others appear to be associated with a specific stage in disease
progression. Deciphering the exact role of microRNAs in oncogenesis is important in order
to improve the diagnosis and treatment of leukemia patients.National Institutes of Health (U.S.) (NIH grant DK068348)National Institutes of Health (U.S.) (NIH Grant 5P01 HL066105)Leukemia & Lymphoma Society of America (Recherche sur le Cancer (ARC) fellowship
IL-6-induced anaemia in rats:Possible pathogenetic implications for anaemia observed in chronic inflammations
Anaemia of chronic disease (ACD) is frequently found in rheumatoid arthritis (RA). In the pathogenesis of ACD both cytokines, such as tumour necrosis factor-alpha (TNF-α), IL-1 and IL-6 as well as a relative deficiency of erythropoietin (EPO), are thought to play a key role. In the present study the role of IL-6 in the pathogenesis of this anaemia was investigated. IL-6 was administered intraperitoneally to rats for 14 sequential days. It appeared that IL-6 was able to induce anaemia. No evidence for suppression of bone marrow erythropoiesis or enhanced sequestration of erythrocytes in the liver was found. However, decreased plasma and bone marrow iron contents were observed in anaemic rats. Blood loss in intestinal tissue was demonstrated using erythrocyte labelling with 99mtechnetium. Histologically this was associated with inflammatory cell infiltration, oedema and bleeding in the intestinal wall. In conclusion, IL-6 induced anaemia in rats. This anaemia was caused by intestinal blood loss.</p
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