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排序方式: 共有2644条查询结果,搜索用时 15 毫秒
1.
Rizzo Manglio Miguel Bluthgen Mara Virginia Recondo Gonzalo Naveira Martin Perfetti Aldo Rizzi Florencia Kuzminin Alejandro Faura Victoria Cerini Matas Videla Alejandro Silva Carlos Lupinacci Lorena Minatta Nicols 《International journal of clinical oncology / Japan Society of Clinical Oncology》2021,26(6):1057-1064
International Journal of Clinical Oncology - Immune-checkpoint inhibitors (ICIs) are standard treatments for metastatic non-small cell lung cancer (NSCLC). Patients with poor performance status... 相似文献
2.
John Lennon Silva Cunha Amanda Almeida Leite Thamiris de Castro Abrantes Lorena Passoni Vervloet Thayn Melo de Lima Morais Gerson de Oliveira Paiva Neto Tatiana Nayara Librio Kimura Snia Maria Soares Ferreira Ricardo Luiz Cavalcanti de Albuquerque‐Júnior Aline Corrêa Abraho Mario Jos Romaach Bruno Augusto Benevenuto de Andrade Oslei Paes de Almeida Ciro Dantas Soares 《Journal of cutaneous pathology》2021,48(1):24-33
3.
4.
Susi Elaine Dal''Belo Lorena Rigo Gaspar Patrícia Maria Berardo Gonçalves Maia Campos 《Skin research and technology》2006,12(4):241-246
BACKGROUND/PURPOSE: The polysaccharide-rich composition of Aloe vera extracts (Aloe barbadensis Miller), often used in cosmetic formulations, may impart moisturizing properties to the product. The aim of this study was to evaluate the effect of cosmetic formulations containing different concentrations of freeze-dried Aloe vera extract on skin hydration, after a single and a 1- and 2-week period of application, by using skin bioengineering techniques. METHODS: Stable formulations containing 5% (w/w) of a trilaureth-4 phosphate-based blend were supplemented with 0.10%, 0.25% or 0.50% (w/w) of freeze-dried Aloe vera extract and applied to the volar forearm of 20 female subjects. Skin conditions in terms of the water content of the stratum corneum and of transepidermal water loss (TEWL) (Corneometer CM 825 and Tewameter TM 210) were analysed before and after a single and 1- and 2-week period of daily application. RESULTS: After a single application, only formulations supplemented with 0.25% and 0.50% (w/w) of Aloe vera extract increased the water content of the stratum corneum, while after the 2-week period application, all formulations containing the extract (0.10%, 0.25% and 0.50%) had the same effect, in both cases as compared with the vehicle. TEWL was not modified after a single and after 1- and 2-week period of application, when compared with the vehicle. CONCLUSION: Our results show that freeze-dried Aloe vera extract is a natural effective ingredient for improving skin hydration, possibly through a humectant mechanism. Consequently, it may be used in moisturizing cosmetic formulations and also as a complement in the treatment of dry skin. 相似文献
5.
Claudio Babiloni Giovanni Frisoni Mircea Steriade Lorena Bresciani Giuliano Binetti Claudio Del Percio Cristina Geroldi Carlo Miniussi Flavio Nobili Guido Rodriguez Filippo Zappasodi Tania Carfagna Paolo M Rossini 《Clinical neurophysiology》2006,117(5):1113-1129
OBJECTIVE: A relationship between brain atrophy and delta rhythmicity (1.5-4 Hz) has been previously explored in Alzheimer's disease (AD) subjects [Fernandez A, Arrazola J, Maestu F, Amo C, Gil-Gregorio P, Wienbruch C, Ortiz T. Correlations of hippocampal atrophy and focal low-frequency magnetic activity in Alzheimer disease: volumetric MR imaging-magnetoencephalographic study. Am J Neuroradiol. 2003 24(3):481-487]. In this study, we tested the hypothesis that such a relationship does exist not only in AD patients but also across the continuum of subjects with mild cognitive impairment (MCI) and AD. METHODS: Resting, eyes-closed EEG data were recorded in 34 MCI and 65 AD subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by LORETA. Cortical EEG sources were correlated with MR-based measurements of lobar brain volume (white and gray matter). RESULTS: A negative correlation was observed between the frontal white matter and the amplitude of frontal delta sources (2-4 Hz) across MCI and AD subjects. CONCLUSIONS: These results confirmed for the first time the hypothesis that the sources of resting delta rhythms (2-4 Hz) are correlated with lobar brain volume across MCI and AD subjects. SIGNIFICANCE: The present findings support, at least at group level, the 'transition hypothesis' of brain structural and functional continuity between MCI and AD. 相似文献
6.
Aaron A. Vogan S. Lorena Ament-Velsquez Eric Bastiaans Ola Wallerman Sven J. Saupe Alexander Suh Hanna Johannesson 《Genome research》2021,31(5):789
The genomes of eukaryotes are full of parasitic sequences known as transposable elements (TEs). Here, we report the discovery of a putative giant tyrosine-recombinase-mobilized DNA transposon, Enterprise, from the model fungus Podospora anserina. Previously, we described a large genomic feature called the Spok block which is notable due to the presence of meiotic drive genes of the Spok gene family. The Spok block ranges from 110 kb to 247 kb and can be present in at least four different genomic locations within P. anserina, despite what is an otherwise highly conserved genome structure. We propose that the reason for its varying positions is that the Spok block is not only capable of meiotic drive but is also capable of transposition. More precisely, the Spok block represents a unique case where the Enterprise has captured the Spoks, thereby parasitizing a resident genomic parasite to become a genomic hyperparasite. Furthermore, we demonstrate that Enterprise (without the Spoks) is found in other fungal lineages, where it can be as large as 70 kb. Lastly, we provide experimental evidence that the Spok block is deleterious, with detrimental effects on spore production in strains which carry it. This union of meiotic drivers and a transposon has created a selfish element of impressive size in Podospora, challenging our perception of how TEs influence genome evolution and broadening the horizons in terms of what the upper limit of transposition may be.Transposable elements (TEs) are major agents of change in eukaryotic genomes. Their ability to selfishly parasitize their host replication machinery has large impacts on both genome size and on gene regulation (Chénais et al. 2012). In extreme cases, TEs can contribute up to 85% of genomic content (Schnable et al. 2009), and expansion and reduction of TEs can result in rapid changes in both genome size and architecture (Haas et al. 2009; Möller and Stukenbrock 2017; Talla et al. 2017). Generally, TEs have small sizes (∼50–12,000 bp) and accomplish these large-scale changes through their sheer number. For example, there are ∼1.1 million Alu elements in the human genome, which have had a large impact on genome evolution (Jurka 2004; Bennett et al. 2008). The largest known cases among Class I retrotransposons are long terminal repeat (LTR) elements that can be as large as 30 kb, but among Class II DNA transposons, Mavericks/Polintons are known to grow as large as 40 kb through the capture of additional open reading frames (ORFs) (Arkhipova and Yushenova 2019). Recently, a behemoth TE named Teratorn was described in teleost fish; it can be up to 182 kb in length, dwarfing all other known TEs. Teratorn has achieved this impressive size by fusing a piggyBac DNA transposon with a herpesvirus, thereby blurring the line between TEs and viruses (Inoue et al. 2017, 2018). Truly massive transposons may be lurking in the depths of many eukaryotic genomes, but the limitations of short-read genome sequencing technologies and the lack of population-level high-quality assemblies may make them difficult to identify.The Spok block is a large genomic feature that was first identified thanks to the presence of the spore killing (Spok) genes in species from the genus Podospora (Grognet et al. 2014; Vogan et al. 2019). The Spoks are selfish genetic elements that bias their transmission to the next generation in a process known as meiotic drive. Here, drive occurs by inducing the death of spores that do not inherit them, through a single protein that operates as both a toxin and an antidote (Grognet et al. 2014; Vogan et al. 2019). The first Spok gene described, Spok1, was discovered in Podospora comata (Grognet et al. 2014). In P. anserina, the homologous gene Spok2 is found at high population frequencies, whereas two other genes of the Spok family, Spok3 and Spok4, are at low to intermediate frequencies (Vogan et al. 2019). Unlike Spok1 and Spok2, however, Spok3 and Spok4 are always associated with a large genomic region (the Spok block). The Spok block can be located at different chromosomal locations in different individuals but is never found more than once in natural strains. The number of Spok genes and the location of the Spok block (which carries Spok3, Spok4, or both) define the overall meiotic driver behavior of a given genome, which can be classified into the so-called Podospora spore killers or Psks (van der Gaag et al. 2000; Vogan et al. 2019). The Spok block stands out not only because of its size, typically around 150 kb, but also because there is otherwise high genome collinearity among strains of P. anserina and with the related species P. comata and P. pauciseta (Vogan et al. 2019).The fact that the Spok block is found at unique genomic positions between otherwise highly similar strains is of prime interest as each novel Spok block position creates a unique meiotic drive type (Psk) due to the intricacies of meiosis in Podospora (Vogan et al. 2019). We therefore set out to determine the mechanism through which the Spok block relocates throughout the genome. Additionally, we annotated the gene content of the various Spok blocks to describe their composition and understand what represents the minimal component of the Spok block. Lastly, we conducted fitness assays to investigate whether the presence of the Spok block imparts any detrimental effects upon the host. 相似文献
7.
Hagood JS Prabhakaran P Kumbla P Salazar L MacEwen MW Barker TH Ortiz LA Schoeb T Siegal GP Alexander CB Pardo A Selman M 《The American journal of pathology》2005,167(2):365-379
Fibroblasts consist of heterogeneous subpopulations that have distinct roles in fibrotic responses. Previously we reported enhanced proliferation in response to fibrogenic growth factors and selective activation of latent transforming growth factor (TGF)-beta in fibroblasts lacking cell surface expression of Thy-1 glycoprotein, suggesting that Thy-1 modulates the fibrogenic potential of fibroblasts. Here we report that compared to controls Thy-1-/- C57BL/6 mice displayed more severe histopathological lung fibrosis, greater accumulation of lung collagen, and increased TGF-beta activation in the lungs 14 days after intratracheal bleomycin. The majority of cells demonstrating TGF-beta activation and myofibroblast differentiation in bleomycin-induced lesions were Thy-1-negative. Histological sections from patients with idiopathic pulmonary fibrosis demonstrated absent Thy-1 staining within fibroblastic foci. Normal lung fibroblasts, in both mice and humans, were predominantly Thy-1-positive. The fibrogenic cytokines interleukin-1 and tumor necrosis factor-alpha induced loss of fibroblast Thy-1 surface expression in vitro, which was associated with Thy-1 shedding, Smad phosphorylation, and myofibroblast differentiation. These results suggest that fibrogenic injury promotes loss of lung fibroblast Thy-1 expression, resulting in enhanced fibrogenesis. 相似文献
8.
Improved survival of ischemic cutaneous and musculocutaneous flaps after vascular endothelial growth factor gene transfer using adeno-associated virus vectors
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Zacchigna S Papa G Antonini A Novati F Moimas S Carrer A Arsic N Zentilin L Visintini V Pascone M Giacca M 《The American journal of pathology》2005,167(4):981-991
A major challenge in reconstructive surgery is flap ischemia, which might benefit from induction of therapeutic angiogenesis. Here we demonstrate the effect of an adeno-associated virus (AAV) vector delivering vascular endothelial growth factor (VEGF)165 in two widely recognized in vivo flap models. For the epigastric flap model, animals were injected subcutaneously with 1.5 x 10(11) particles of AAV-VEGF at day 0, 7, or 14 before flap dissection. In the transverse rectus abdominis musculocutaneous flap model, AAV-VEGF was injected intramuscularly. The delivery of AAV-VEGF significantly improved flap survival in both models, reducing necrosis in all treatment groups compared to controls. The most notable results were obtained by administering the vector 14 days before flap dissection. In the transverse rectus abdominis musculocutaneous flap model, AAV-VEGF reduced the necrotic area by >50% at 1 week after surgery, with a highly significant improvement in the healing process throughout the following 2 weeks. The therapeutic effect of AAV-VEGF on flap survival was confirmed by histological evidence of neoangiogenesis in the formation of large numbers of CD31-positive capillaries and alpha-smooth muscle actin-positive arteriolae, particularly evident at the border between viable and necrotic tissue. These results underscore the efficacy of VEGF-induced neovascularization for the prevention of tissue ischemia and the improvement of flap survival in reconstructive surgery. 相似文献
9.
Zhan Y Brown LE Deliyannis G Seah S Wijburg OL Price J Strugnell RA O'Connell PJ Lew AM 《Immunologic research》2004,30(1):1-14
The most common models of CD4 T-cell deficiency are mice exogenously injected with anti-CD4 antibody (Ab), CD4 knockout (CD4−/−) and major histocompatibility complex (MHC) class II knockout (class II−/−) mice. We recently described the anti-CD4 Ab transgenic mouse (GK) as an improved CD4 cell-deficient model. This review compares
this new GK mouse model with the widely available class II−/− and CD4−/− mice, when exposed to complex antigens (foreign grafts and during bacterial or viral infection). We highlight here the cytometric
and functional differences (including Ab isotype, viral or bacterial clearance, and graft survival) among these CD4 cell-deficient
models. For example, whereas grafts are generally rejected in class II−/− and CD4−/− mice as quickly as in wild-type mice, they survive longer in GK mice. Also, CD4−/− mice produce IgG against both simple model and complex antigens, but class II−/− and GK mice produce small amounts of IgG2a against complex antigens but not simple model antigens. These differences harbinger
the caveats in the use of these various mice. 相似文献
10.
Sierra C Lascurain R Pereyra A Guevara J Martínez G Agundis C Zenteno E Vázquez L 《Developmental and comparative immunology》2005,29(2):113-121
Using a spectrophotometric NBT reduction assay and phagocytosis, we identified that production of superoxide anions and phagocytic activity of hemocytes from Macrobrachium rosenbergii were significantly higher in the presence of rat, rabbit, and chicken erythrocytes than with human, pig, or horse erythrocytes. Hemocytes stimulated with MrL, MrLMab, or PMA increased 4.7, 5.1, and 6.1 fold, respectively, the oxidative response as compared to non-stimulated hemocytes. MrLMab together with MrL increased 5.7 fold the oxidative capacity of hemocytes as compared to non-stimulated cells. These effects were inhibited with 100 mM GalNAc, GlcNAc, or Neu5Ac and 0.2 microM of sialylated submaxillary gland mucin and fetuin. Piroxicam inhibited (P < 0.05) the production of O(2)(-) induced by MrL, whereas iodoacetamide inhibited the effect of MrLMAb (P < 0.05) in a dose-dependent manner. Our results suggest that MrLMab might activate the oxidative burst through the metabolism of glucose as opposed to MrL which utilizes NADPH-independent mechanisms, very probably through pro-inflammatory metabolites. 相似文献