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101.
The Herpesvirus capsid surface protein, VP26, and the majority of the tegument proteins are dispensable for capsid transport toward the nucleus 下载免费PDF全文
Antinone SE Shubeita GT Coller KE Lee JI Haverlock-Moyns S Gross SP Smith GA 《Journal of virology》2006,80(11):5494-5498
Upon entering a cell, alphaherpesvirus capsids are transported toward the minus ends of microtubules and ultimately deposit virus DNA within the host nucleus. The virus proteins that mediate this centripetal transport are unknown but are expected to be either viral tegument proteins, which are a group of capsid-associated proteins, or a surface component of the capsid itself. Starting with derivatives of pseudorabies virus that encode a fluorescent protein fused to a structural component of the virus, we have made a collection of 12 mutant viruses that lack either the VP26 capsid protein or an individual tegument protein. Using live-cell fluorescence microscopy, we tracked individual virus particles in axons following infection of primary sensory neurons. Quantitative analysis of the VP26-null virus indicates that this protein plays no observable role in capsid transport. Furthermore, viruses lacking tegument proteins that are nonessential for virus propagation in cell culture were also competent for axonal transport. These results indicate that a protein essential for viral propagation mediates transport of the capsid to the nucleus. 相似文献
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Melissa M. Page Kurtis D. Salway Yuen Kwong Ip Shit F. Chew Sarah A. Warren James S. Ballantyne Jeffrey A. Stuart 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2010,180(3):361-369
The African slender lungfish, Protopterus dolloi, is highly adapted to withstand periods of drought by secreting a mucous cocoon and estivating for periods of months to years. Estivation is similar to the diapause and hibernation of other animal species in that it is characterized by negligible activity and a profoundly depressed metabolic rate. As is typically observed in quiescent states, estivating P. dolloi are resistant to environmental stresses. We tested the hypothesis that P. dolloi enhances stress resistance during estivation by upregulating intracellular antioxidant defences in brain and heart tissues. We found that most of the major intracellular antioxidant enzymes, including the mitochondrial superoxide dismutase, cytosolic superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase, were upregulated in brain tissue of lungfish that had estivated for 60 days. Several of these enzymes were also elevated in heart tissue of estivators. These changes were not due to food deprivation, as they did not occur in a group of fish that were deprived of food but maintained in water for the same period of time. We found little evidence of tissue oxidative damage in estivators. Products of lipid peroxidation (4-hydroxynonenal adducts) and oxidative protein damage (carbonylation) were similar in estivating and control lungfish. However, protein nitrotyrosine levels were elevated in brain tissue of estivators. Taken together, these data indicate that estivating P. dolloi have enhanced oxidative stress resistance in brain and heart due to a significant upregulation of intracellular antioxidant capacity. 相似文献
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Chandana Basu Mallick Florin Mircea Iliescu M?rt M?ls Sarah Hill Rakesh Tamang Gyaneshwer Chaubey Rie Goto Simon Y. W. Ho Irene Gallego Romero Federica Crivellaro Georgi Hudjashov Niraj Rai Mait Metspalu C. G. Nicholas Mascie-Taylor Ramasamy Pitchappan Lalji Singh Marta Mirazon-Lahr Kumarasamy Thangaraj Richard Villems Toomas Kivisild 《PLoS genetics》2013,9(11)
Skin pigmentation is one of the most variable phenotypic traits in humans. A non-synonymous substitution (rs1426654) in the third exon of SLC24A5 accounts for lighter skin in Europeans but not in East Asians. A previous genome-wide association study carried out in a heterogeneous sample of UK immigrants of South Asian descent suggested that this gene also contributes significantly to skin pigmentation variation among South Asians. In the present study, we have quantitatively assessed skin pigmentation for a largely homogeneous cohort of 1228 individuals from the Southern region of the Indian subcontinent. Our data confirm significant association of rs1426654 SNP with skin pigmentation, explaining about 27% of total phenotypic variation in the cohort studied. Our extensive survey of the polymorphism in 1573 individuals from 54 ethnic populations across the Indian subcontinent reveals wide presence of the derived-A allele, although the frequencies vary substantially among populations. We also show that the geospatial pattern of this allele is complex, but most importantly, reflects strong influence of language, geography and demographic history of the populations. Sequencing 11.74 kb of SLC24A5 in 95 individuals worldwide reveals that the rs1426654-A alleles in South Asian and West Eurasian populations are monophyletic and occur on the background of a common haplotype that is characterized by low genetic diversity. We date the coalescence of the light skin associated allele at 22–28 KYA. Both our sequence and genome-wide genotype data confirm that this gene has been a target for positive selection among Europeans. However, the latter also shows additional evidence of selection in populations of the Middle East, Central Asia, Pakistan and North India but not in South India. 相似文献
107.
Mohamed A. Hassan Sarah Abd El-Aziz Horeya M. Elbadry Samy A. El-Aassar Tamer M. Tamer 《Saudi Journal of Biological Sciences》2022,29(4):2978
Multi-drug resistant (MDR) bacteria associated with wounds are extremely escalating. This study aims to survey different wounds in Alexandria hospitals, North Egypt, to explore the prevalence and characteristics of MDR bacteria for future utilization in antibacterial wound dressing designs. Among various bacterial isolates, we determined 22 MDR bacteria could resist different classes of antibiotics. The collected samples exhibited the prevalence of mono-bacterial infections (60%), while 40% included poly-bacterial species due to previous antibiotic administration. Moreover, Gram-negative bacteria showed dominance with a ratio of 63.6%, while Gram-positive bacteria reported 36.4%. Subsequently, the five most virulent bacteria were identified following the molecular approach by 16S rRNA and physiological properties using the VITEK 2 automated system. They were deposited in GenBank as Staphylococcus haemolyticus MST1 (), Pseudomonas aeruginosa MST2 ( KY550377), Klebsiella pneumoniae MST3 ( KY550378), Escherichia coli MST4 ( KY550379), and Escherichia coli MST5 ( KY550380). In terms of isolation source, S. haemolyticus MST1 was isolated from a traumatic wound, while P. aeruginosa MST2 and E. coli MST4 were procured from hernia surgical wounds, and K. pneumoniae MST3 and E. coli MST5 were obtained from diabetic foot ulcers. Antibiotic sensitivity tests exposed that K. pneumoniae MST3, E. coli MST4, and E. coli MST5 are extended-spectrum β-lactamases (ESBLs) bacteria. Moreover, S. haemolyticus MST1 belongs to the methicillin-resistant coagulase-negative staphylococcus (MRCoNS), whereas P. aeruginosa MST2 exhibited resistance to common empirical bactericidal antibiotics. Overall, the study provides new insights into the prevalent MDR bacteria in Egypt for further use as specific models in formulating antibacterial wound dressings. KY550381相似文献
108.
Sonia Johnson Christian DaltonLocke John Baker Charlotte Hanlon Tatiana Taylor Salisbury Matt Fossey Karen Newbigging Sarah E. Carr Jennifer Hensel Giuseppe Carr Urs Hepp Constanza Caneo Justin J. Needle Brynmor LloydEvans 《World psychiatry》2022,21(2):220
Acute services for mental health crises are very important to service users and their supporters, and consume a substantial share of mental health resources in many countries. However, acute care is often unpopular and sometimes coercive, and the evidence on which models are best for patient experience and outcomes remains surprisingly limited, in part reflecting challenges in conducting studies with people in crisis. Evidence on best approaches to initial assessment and immediate management is particularly lacking, but some innovative models involving extended assessment, brief interventions, and diversifying settings and strategies for providing support are potentially helpful. Acute wards continue to be central in the intensive treatment phase following a crisis, but new approaches need to be developed, evaluated and implemented to reducing coercion, addressing trauma, diversifying treatments and the inpatient workforce, and making decision‐making and care collaborative. Intensive home treatment services, acute day units, and community crisis services have supporting evidence in diverting some service users from hospital admission: a greater understanding of how best to implement them in a wide range of contexts and what works best for which service users would be valuable. Approaches to crisis management in the voluntary sector are more flexible and informal: such services have potential to complement and provide valuable learning for statutory sector services, especially for groups who tend to be underserved or disengaged. Such approaches often involve staff with personal experience of mental health crises, who have important potential roles in improving quality of acute care across sectors. Large gaps exist in many low‐ and middle‐income countries, fuelled by poor access to quality mental health care. Responses need to build on a foundation of existing community responses and contextually relevant evidence. The necessity of moving outside formal systems in low‐resource settings may lead to wider learning from locally embedded strategies. 相似文献
109.
Vronique Roig-Zamboni Sarah Barelier Robert Dixon Nicola F. Galley Amani Ghanem Quoc Phong Nguyen Hloize Cahuzac Bartomiej Salamaga Peter J. Davis Yves Bourne Stphane Mesnage Florence Vincent 《The Journal of biological chemistry》2022,298(5)
The cleavage of septal peptidoglycan at the end of cell division facilitates the separation of the two daughter cells. The hydrolases involved in this process (called autolysins) are potentially lethal enzymes that can cause cell death; their activity, therefore, must be tightly controlled during cell growth. In Enterococcus faecalis, the N-acetylglucosaminidase AtlA plays a predominant role in cell separation. atlA mutants form long cell chains and are significantly less virulent in the zebrafish model of infection. The attenuated virulence of atlA mutants is underpinned by a limited dissemination of bacterial chains in the host organism and a more efficient uptake by phagocytes that clear the infection. AtlA has structural homologs in other important pathogens, such as Listeria monocytogenes and Salmonella typhimurium, and therefore represents an attractive model to design new inhibitors of bacterial pathogenesis. Here, we provide a 1.45 Å crystal structure of the E. faecalis AtlA catalytic domain that reveals a closed conformation of a conserved β-hairpin and a complex network of hydrogen bonds that bring two catalytic residues to the ideal distance for an inverting mechanism. Based on the model of the AtlA–substrate complex, we identify key residues critical for substrate recognition and septum cleavage during bacterial growth. We propose that this work will provide useful information for the rational design of specific inhibitors targeting this enterococcal virulence factor and its orthologs in other pathogens. 相似文献
110.
Gaston Tona Lutete Ghyslain Mombo-Ngoma Serge-Brice Assi Jude D. Bigoga Felix Koukouikila-Koussounda Nsengi Y. Ntamabyaliro Francine Ntoumi Selidji T. Agnandji Mirjam Groger Jangsik Shin Isabelle Borghini-Fuhrer Sarah Arbe-Barnes Stephen J. Allen Peter G. Kremsner Robert Miller Stephan Duparc Michael Ramharter the CANTAM study group 《PLoS medicine》2021,18(6)
BackgroundIn Phase II/III randomized controlled clinical trials for the treatment of acute uncomplicated malaria, pyronaridine–artesunate demonstrated high efficacy and a safety profile consistent with that of comparators, except that asymptomatic, mainly mild-to-moderate transient increases in liver aminotransferases were reported for some patients. Hepatic safety, tolerability, and effectiveness have not been previously assessed under real-world conditions in Africa.Methods and findingsThis single-arm, open-label, cohort event monitoring study was conducted at 6 health centers in Cameroon, Democratic Republic of Congo, Gabon, Ivory Coast, and Republic of Congo between June 2017 and April 2019. The trial protocol as closely as possible resembled real-world clinical practice for the treatment of malaria at the centers. Eligible patients were adults or children of either sex, weighing at least 5 kg, with acute uncomplicated malaria who did not have contraindications for pyronaridine–artesunate treatment as per the summary of product characteristics. Patients received fixed-dose pyronaridine–artesunate once daily for 3 days, dosed by body weight, without regard to food intake. A tablet formulation was used in adults and adolescents and a pediatric granule formulation in children and infants under 20 kg body weight. The primary outcome was the hepatic event incidence, defined as the appearance of the clinical signs and symptoms of hepatotoxicity confirmed by a >2× rise in alanine aminotransferase/aspartate aminotransferase (ALT/AST) versus baseline in patients with baseline ALT/AST >2× the upper limit of normal (ULN). As a secondary outcome, this was assessed in patients with ALT/AST >2× ULN prior to treatment versus a matched cohort of patients with normal baseline ALT/AST. The safety population comprised 7,154 patients, of mean age 13.9 years (standard deviation (SD) 14.6), around half of whom were male (3,569 [49.9%]). Patients experienced 8,560 malaria episodes; 158 occurred in patients with baseline ALT/AST elevations >2×ULN. No protocol-defined hepatic events occurred following pyronaridine–artesunate treatment of malaria patients with or without baseline hepatic dysfunction. Thus, no cohort comparison could be undertaken. Also, as postbaseline clinical chemistry was only performed where clinically indicated, postbaseline ALT/AST levels were not systematically assessed for all patients. Adverse events of any cause occurred in 20.8% (1,490/7,154) of patients, most frequently pyrexia (5.1% [366/7,154]) and vomiting (4.2% [303/7,154]). Adjusting for Plasmodium falciparum reinfection, clinical effectiveness at day 28 was 98.6% ([7,369/7,746] 95% confidence interval (CI) 98.3 to 98.9) in the per-protocol population. There was no indication that comorbidities or malnutrition adversely affected outcomes. The key study limitation was that postbaseline clinical biochemistry was only evaluated when clinically indicated.ConclusionsPyronaridine–artesunate had good tolerability and effectiveness in a representative African population under conditions similar to everyday clinical practice. These findings support pyronaridine–artesunate as an operationally useful addition to the management of acute uncomplicated malaria.Trial registrationClinicalTrials.gov .Gaston Tona Lutete and co-workers report on safety and effectiveness of the antimalarial drug pyronaridine-artesunate in African countries. NCT03201770相似文献