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41.
Virus Genes - Rotavirus A is a dynamically evolving pathogen causing acute gastroenteritis in children during the first years of life. In the present study, we conducted a phylodynamic analysis...  相似文献   
42.
Peri-necrotic tumor regions have been found to be a source of cancer stem cells (CSC), important in tumor recurrence. Necrotic and peri-necrotic tumor zones have poor vascular supply, limiting effective exposure to systemically administered therapeutics. Therefore, there is a critical need to develop agents that can effectively target these relatively protected tumor areas. We have developed a multi-property nanoplatform with necrosis avidity, fluorescence imaging and X-ray tracking capabilities to evaluate its feasibility for therapeutic drug delivery. The developed nanoparticle consists of three elements: poly(ethylene glycol)-block-poly(ε-caprolactone) as the biodegradable carrier; hypericin as a natural compound with fluorescence and necrosis avidity; and gold nanoparticles for X-ray tracking. This reproducible nanoparticle has a hydrodynamic size of 103.9 ± 1.7 nm with a uniform spherical morphology (polydispersity index = 0.12). The nanoparticle shows safety with systemic administration and a stable 30 day profile. Intravenous nanoparticle injection into a subcutaneous tumor-bearing mouse and intra-arterial nanoparticle injection into rabbits bearing VX2 orthotopic liver tumors resulted in fluorescence and X-ray attenuation within the tumors. In addition, ex vivo and histological analysis confirmed the accumulation of hypericin and gold in areas of necrosis and peri-necrosis. This nanoplatform, therefore, has the potential to enhance putative therapeutic drug delivery to necrotic and peri-necrotic areas, and may also have an application for monitoring early response to anti-tumor therapies.

Au-Hyp-NP developed by encapsulation of gold and hypericin into PEG-PCL nanoplatform for fluorescence and X-ray tracking with tumor necrosis targeting.  相似文献   
43.
BackgroundHeated tobacco products (HTP) are new forms of tobacco consumption with limited information available on their use among the general population. Our objective was to analyze the prevalence and associations of use of HTP across 11 countries in Europe.MethodsWithin the TackSHS Project, in 2017–2018 we conducted a cross-sectional study with information on HTP use in the following countries: Bulgaria, England, France, Germany, Greece, Italy, Latvia, Poland, Portugal, Romania and Spain. In each country, face-to-face interviews were performed on a representative sample of around 1,000 subjects aged ≥15 years, for a total of 10,839 subjects.ResultsOverall, 27.8% of study participants were aware of HTPs, 1.8% were ever HTP users (ranging from 0.6% in Spain to 8.3% in Greece), and 0.1% were current users. Men were more frequently HTP ever users than women (adjusted odds ratio [aOR] 1.47; 95% confidence interval [CI], 1.11–1.95). Ever HTP use was inversely related to age (P for trend <0.001) and more frequent in ex-smokers (compared with never smokers, aOR 4.32; 95% CI, 2.69–6.95) and current smokers (aOR 8.35; 95% CI, 5.67–12.28), and in electronic cigarette past users (compared with never users, aOR 5.48; 95% CI, 3.46–8.68) and current users (aOR 5.92; 95% CI, 3.73–9.40).ConclusionsIn 2017–2018, HTP use was still limited in Europe among the general population; however, the dual use of these products, their high use among younger generations, and the interest of non-smokers in these products are worrying and indicate the need for close monitoring in terms of prevalence and the characteristics of users.Key words: heated tobacco products, heat-not-burn tobacco products, IQOS, survey, Europe  相似文献   
44.
Ophthalmic-ethmoidal dural arteriovenous fistula (DAVFs) is a rare type of dural arteriovenous fistulas and usually presenting with spontaneous subarachnoid hemorrhage, subdural hemorrhage or ocular symptoms. We present a case of a 59-year old gentleman presenting with acute headache, vomiting and generalized weakness. CT study of the brain revealed a large left frontal hematoma and abnormal aneurysmal sac with dilated cortical vein, communicating with the superior sagittal sinus. Conventional angiography confirmed diagnosis of ruptured ophthalmic-ethmoidal DAVF, resulting in a frontal intra-axial hemorrhage. Anterior fossa DAVFs are extremely rare, difficult to diagnose and treat. CT angiography is initial method of diagnosis, but digital substruction angiography remains the gold standard of confirming dural fistulas.  相似文献   
45.
BackgroundWith greater use of social media platforms for promotions of research articles, retracted articles tend to receive approximately the same attention. We systematically analyzed retracted articles from retractionwatch.com to look at the Altmetric Attention Scores (AAS) garnered over a period of time in order to highlight the role of social media and other platforms in advertising retracted articles and its effect on the spread of misinformation.MethodsRetractionwatch.com was searched for coronavirus disease 2019 related retracted papers on November 6th, 2021. Articles were excluded based on lack of digital object identifier (DOI), if they were preprint articles, absent AAS, and incomplete AAS of pre retraction, post retraction, or both scores.ResultsA total of 196 articles were found on the Retraction Watch website of which 189 were retracted papers and 7 were expression of concern (EOC). We then identified 175 articles after excluding those that did not have a DOI and 30 preprint articles were also excluded giving 145 articles. Further exclusion of articles with absent AAS and incomplete AAS resulted in a total of 22 articles.ConclusionRetracted articles receive significant online attention. Twitter and Mendeley were the most popular medium for publicizing retracted articles, therefore more focus should be given by journals and their Twitter accounts to discredit all their retracted articles. Preprints should be reconsidered as a whole by journals due to the huge risk they carry in disseminating false information.  相似文献   
46.
Benzophenone-3 is a putative endocrine disrupting chemical and common ingredient in sunscreens. The potential of endocrine disrupting chemicals to act as agonists or antagonists in critical hormonally regulated processes, such as mammary gland development and mammary tumorigenesis, demands evaluation of its potential in promoting breast cancer. This study identifies the effects of BP-3 on mammary tumorigenesis with high-fat diet during puberty versus adulthood in Trp53-null transplant BALB/c mice. Benzophenone-3 exposure yielded levels in urine similar to humans subjected to heavy topical sunscreen exposure. Benzophenone-3 was protective for epithelial tumorigenesis in mice fed lifelong low-fat diet, while promotional for epithelial tumorigenesis in mice fed adult high-fat diet. Benzophenone-3 increased tumor cell proliferation, decreased tumor cell apoptosis, and increased tumor vascularity dependent on specific dietary regimen and tumor histopathology. Even in instances of an ostensibly protective effect, other parameters suggest greater risk. Although benzophenone-3 seemed protective on low-fat diet, spindle cell tumors arising in these mice showed increased proliferation and decreased apoptosis. This points to a need for further studies of benzophenone-3 in both animal models and humans as a potential breast cancer risk factor, as well as a more general need to evaluate endocrine disrupting chemicals in varying dietary contexts.  相似文献   
47.
BackgroundHomologous recombination deficiency (HRD) is a phenotype that is characterized by the inability of a cell to effectively repair DNA double-strand breaks using the homologous recombination repair (HRR) pathway. Loss-of-function genes involved in this pathway can sensitize tumors to poly(adenosine diphosphate [ADP]-ribose) polymerase (PARP) inhibitors and platinum-based chemotherapy, which target the destruction of cancer cells by working in concert with HRD through synthetic lethality. However, to identify patients with these tumors, it is vital to understand how to best measure homologous repair (HR) status and to characterize the level of alignment in these measurements across different diagnostic platforms. A key current challenge is that there is no standardized method to define, measure, and report HR status using diagnostics in the clinical setting.MethodsFriends of Cancer Research convened a consortium of project partners from key healthcare sectors to address concerns about the lack of consistency in the way HRD is defined and methods for measuring HR status.ResultsThis publication provides findings from the group’s discussions that identified opportunities to align the definition of HRD and the parameters that contribute to the determination of HR status. The consortium proposed recommendations and best practices to benefit the broader cancer community.ConclusionOverall, this publication provides additional perspectives for scientist, physician, laboratory, and patient communities to contextualize the definition of HRD and various platforms that are used to measure HRD in tumors.  相似文献   
48.
49.
Background and purpose We have previously shown that early fracture callus of rat rib has viscoelastic and contractile properties resembling those of smooth muscle. The cells responsible for this contractility have been hypothesized to be myofibroblast-like in nature. In soft-tissue healing, force generated by contraction of myofibroblasts promotes healing. Accordingly, we tried to identify myofibroblast-like cells in early fibrous callus.

Animals and methods Calluses from rat rib fractures were removed 7, 14, and 21 days after fracture and unfractured ribs acted as controls. All tissues were analyzed using qPCR and immunohistochemistry. We analyzed expression of smooth muscle- and myofibroblast-associated genes and proteins including alpha smooth muscle actin (αSMA), non-muscle myosin, fibronectin extra domain A variant (EDA-fibronectin), OB-cadherin, connexin-43, basic calponin (h1CaP), and h-caldesmon.

Results In calluses at 7 days post-fracture, there were statistically significant increases in expression of αSMA mRNA (2.5 fold), h1CaP mRNA (2.1 fold), EDA-fibronectin mRNA (14 fold), and connexin-43 mRNA (1.8 fold) compared to unfractured ribs, and by 21 days post-fracture mRNA expression in calluses had decreased to levels approaching those in unfractured rib. Immunohistochemistry of 7 day fibrous callus localized calponin, EDA-fibronectin and co-immunolabeling of OB-cadherin and αSMA (thus confirming a myofibroblastic phenotype) within various cell populations.

Interpretation This study provides further evidence that early rat rib callus is not only smooth muscle-like in nature but also contains a notable population of cells that have a distinct myofibroblastic phenotype. The presence of these cells indicates that in vivo contraction of early callus is a mechanism that may occur in fractures so as to facilitate healing, as it does in soft tissue wound repair.  相似文献   
50.
Vertical transmission of tick-borne encephalitis virus (TBEV) between generations of the small rodents—red voles Myodes rutilus Pallas (previously known as Clethrionomys rutilus Pallas) was shown for naturally infected reservoir hosts and after experimental infection with different sublethal doses of the viral strains. For wild red voles and for their progeny born in 240–280 days after experimental infection of their parents the TBEV was detected in up to 90% of samples by RT-PCR, ELISA and bioassays. Small amounts of the TBEV RNA found in embryos, placenta and blood cells could serve as evidence of prenatal transmission. Postnatal transfer of the virus might occur through the rodent milk. Analysis of the TBEV E gene nucleotide sequences of RT-PCR products revealed missense mutations resulting in amino acid substitution K280Q in newborn red vole in comparison with its parent female.Taken together, the data confirmed the TBEV vertical transmission among generations of its adapted mammal reservoir hosts. The virus transfer might occur before, during and/or after birth of the small rodents with high frequencies. In the wild it could provide the TBEV long-term persistence in mammal hosts without an (any) involvement of arthropod vectors thus selecting dangerous mammal-adapted variants.  相似文献   
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