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1.
The nonstructural protein 3 (NS3) of Dengue virus (DV) is a multifunctional enzyme carrying activities involved in viral RNA replication and capping: helicase, nucleoside 5'-triphosphatase (NTPase), and RNA 5'-triphosphatase (RTPase). Here, a 54-kDa C-terminal domain of NS3 (DeltaNS3) bearing all three activities was expressed as a recombinant protein. Structure-based sequence analysis in comparison with Hepatitis C virus (HCV) helicase indicates the presence of a HCV-helicase-like catalytic core domain in the N-terminal part of DeltaNS3, whereas the C-terminal part seems to be different. In this report, we show that the RTPase activity of DeltaNS3 is Mg2+-dependent as are both helicase and NTPase activities. Mutational analysis shows that the RTPase activity requires an intact NTPase/helicase Walker B motif in the helicase core, consistent with the fact that such motifs are involved in the coordination of Mg2+. The R513A substitution in the C-terminal domain of DeltaNS3 abrogates helicase activity and strongly diminishes RTPase activity, indicating that both activities are functionally coupled. DV RTPase seems to belong to a new class of Mg2+-dependent RTPases, which use the active center of the helicase/NTPase catalytic core in conjunction with elements in the C-terminal domain. 相似文献
2.
Carola Buscemi Yvelise Ferro Roberta Pujia Elisa Mazza Giada Boragina Angela Sciacqua Salvatore Piro Arturo Pujia Giorgio Sesti Silvio Buscemi Tiziana Montalcini 《Nutrients》2021,13(6)
Elderly women exhibit a high risk of type 2 diabetes (T2D), but no definitive data exist about the possible role of postmenopausal increases in visceral adiposity, the loss of lean body mass, or decreases in the sum of the lean mass of arms and legs (appendicular skeletal muscle mass (ASMM)). This retrospective, longitudinal study investigated whether body composition (bioelectrical impedance analysis) predicted the development of impaired fasting glucose (IFG) or T2D in a cohort of 159 elderly women (age: 71 ± 5 years, follow-up: 94 months) from southern Italy (Clinical Nutrition and Geriatric Units of the “Mater Domini” University Hospital in Catanzaro, Calabria region, and the “P. Giaccone ”University Hospital in Palermo, Sicily region). Sarcopenia was defined in a subgroup of 128 women according to the EWGSOP criteria as the presence of low muscle strength (handgrip strength <16 kg) plus low muscle mass (reported as appendicular skeletal muscle mass <15 kg). Participants with a low ASMM had a higher IFG/T2D incidence than those with a normal ASMM (17% vs. 6%, p-adjusted = 0.044); this finding was independent of BMI, fat mass, waist circumference, and habitual fat intake (OR = 3.81, p = 0.034). A higher incidence of IFG/T2D was observed in the subgroup with sarcopenia than those without sarcopenia (33% vs. 7%, p-adjusted = 0.005) independent of BMI and fat mass (OR = 6.75, p = 0.007). In conclusion, this study demonstrates that elderly women with low ASMM had a higher probability of developing IFG/T2D. Further studies are needed to confirm these results in men and in other age groups. 相似文献
3.
Willy Palm Erin Webb Cristina Hernández-Quevedo Giada Scarpetti Suszy Lessof Luigi Siciliani Ewout van Ginneken 《Health policy (Amsterdam, Netherlands)》2021,125(3):341-350
This study identifies gaps in universal health coverage in the European Union, using a questionnaire sent to the Health Systems and Policy Monitor network of the European Observatory on Health Systems and Policies. The questionnaire was based on a conceptual framework with four access dimensions: population coverage, service coverage, cost coverage, and service access. With respect to population coverage, groups often excluded from statutory coverage include asylum seekers and irregular residents. Some countries exclude certain social-professional groups (e.g. civil servants) from statutory coverage but cover these groups under alternative schemes. In terms of service coverage, excluded or restricted services include optical treatments, dental care, physiotherapy, reproductive health services, and psychotherapy. Early access to new and expensive pharmaceuticals is a concern, especially for rare diseases and cancers. As to cost coverage, some countries introduced protective measures for vulnerable patients in the form of exemptions or ceilings from user chargers, especially for deprived groups or patients with accumulation of out-of-pocket spending. For service access, common issues are low perceived quality and long waiting times, which are exacerbated for rural residents who also face barriers from physical distance. Some groups may lack physical or mental ability to properly formulate their request for care. Currently, available indicators fail to capture the underlying causes of gaps in coverage and access. 相似文献
4.
Michael Feyder PhD Carina Plewnia BSc Ori J. Lieberman BSc Giada Spigolon PhD Alessandro Piccin PhD Lidia Urbina BSc Benjamin Dehay PhD Qin Li PhD Per Nilsson PhD Mikael Altun PhD Emanuela Santini PhD David Sulzer PhD Erwan Bezard PhD Anders Borgkvist PhD Gilberto Fisone PhD 《Movement disorders》2021,36(5):1137-1146
5.
Pelizzaro Filippo Kitenge Maria Piera Cardin Romilda Ponzoni Alberto Cillo Umberto Vitale Alessandro Businello Gianluca Munari Giada Fassan Matteo Farinati Fabio 《Clinical and experimental medicine》2021,21(4):675-682
Clinical and Experimental Medicine - We aimed to explore the activation of monoacylglycerol lipase (MAGL)/cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2) axis in hepatocellular carcinoma (HCC),... 相似文献
6.
Giada Pizzuti Dacia Di Renzo Antonello Persico Pierluigi Lelli Chiesa 《Journal of Ultrasound》2021,24(1):81
Cystic dysplasia of the rete testis (CDT) is a rare cause of scrotal swelling in children. It is a congenital disorder and it can be associated with other genitourinary abnormalities. At present, there is no clear consensus on treatment. Surgical approach has traditionally been the treatment of choice, while, more recently, conservative approach has been applied, justified by the benign nature of the lesion and after few cases of spontaneous regression have been documented. Ultrasonography, supported by negative tumor markers, plays a key role in the diagnostic work up and during observational follow-up. We report a further case of spontaneous regression of suspected CDT in an 18-month-old boy, who has been followed with clinic and ultrasonographic checks. 相似文献
7.
Mirko Tarocchi Simone Polvani Giada Marroncini Andrea Galli 《World journal of gastroenterology : WJG》2014,20(33):11630-11640
Hepatitis B virus (HBV) infection is a global public health problem with approximately 2 billion people that have been exposed to the virus. HBV is a member of a family of small, enveloped DNA viruses called hepadnaviruses, and has a preferential tropism for hepatocytes of mammals and birds. Epidemiological studies have proved a strong correlation between chronic hepatitis B virus infection and the development of hepatocellular carcinoma (HCC). HCC is the fifth most common malignancy with about 700000 new cases each year, and more than 50% of them arise in HBV carriers. A large number of studies describe the way in which HBV can contribute to HCC development. Multiple mechanisms have been proposed, including the accumulation of genetic damage due to immune-mediated hepatic inflammation and the induction of oxidative stress. There is evidence of the direct effects of the viral proteins HBx and HBs on the cell biology. Integration of HBV-DNA into the human genome is considered an early event in the carcinogenic process and can induce, through insertional mutagenesis, the alteration of gene expression and chromosomal instability. HBV has also epigenetic effects through the modification of the genomic methylation status. Furthermore, the virus plays an important role in the regulation of microRNA expression. This review will summarize the many mechanisms involved in HBV-related liver carcinogenesis. 相似文献
8.
9.
Carnevale D Mascio G D'Andrea I Fardella V Bell RD Branchi I Pallante F Zlokovic B Yan SS Lembo G 《Hypertension》2012,60(1):188-197
Although epidemiological data associate hypertension with a strong predisposition to develop Alzheimer disease, no mechanistic explanation exists so far. We developed a model of hypertension, obtained by transverse aortic constriction, leading to alterations typical of Alzheimer disease, such as amyloid plaques, neuroinflammation, blood-brain barrier dysfunction, and cognitive impairment, shown here for the first time. The aim of this work was to investigate the mechanisms involved in Alzheimer disease of hypertensive mice. We focused on receptor for advanced glycation end products (RAGE) that critically regulates Aβ transport at the blood-brain barrier and could be influenced by vascular factors. The hypertensive challenge had an early and sustained effect on RAGE upregulation in brain vessels of the cortex and hippocampus. Interestingly, RAGE inhibition protected from hypertension-induced Alzheimer pathology, as showed by rescue from cognitive impairment and parenchymal Aβ deposition. The increased RAGE expression in transverse aortic coarctation mice was induced by increased circulating advanced glycation end products and sustained by their later deposition in brain vessels. Interestingly, a daily treatment with an advanced glycation end product inhibitor or antioxidant prevented the development of Alzheimer traits. So far, Alzheimer pathology in experimental animal models has been recognized using only transgenic mice overexpressing amyloid precursor. This is the first study demonstrating that a chronic vascular insult can activate brain vascular RAGE, favoring parenchymal Aβ deposition and the onset of cognitive deterioration. Overall we demonstrate that RAGE activation in brain vessels is a crucial pathogenetic event in hypertension-induced Alzheimer disease, suggesting that inhibiting this target can limit the onset of vascular-related Alzheimer disease. 相似文献
10.