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421.
Anthony T. Tan Martin Linster Chee Wah Tan Nina Le Bert Wan Ni Chia Kamini Kunasegaran Yan Zhuang Christine Y.L. Tham Adeline Chia Gavin J.D. Smith Barnaby Young Shirin Kalimuddin Jenny G.H. Low David Lye Lin-Fa Wang Antonio Bertoletti 《Cell reports》2021,34(6):108728
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422.
Jane J. Kim Kate T. Simms James Killen Megan A. Smith Emily A. Burger Stephen Sy Catherine Regan Karen Canfell 《PLoS medicine》2021,18(3)
BackgroundA nonavalent human papillomavirus (HPV) vaccine has been licensed for use in women and men up to age 45 years in the United States. The cost-effectiveness of HPV vaccination for women and men aged 30 to 45 years in the context of cervical cancer screening practice was evaluated to inform national guidelines.Methods and findingsWe utilized 2 independent HPV microsimulation models to evaluate the cost-effectiveness of extending the upper age limit of HPV vaccination in women (from age 26 years) and men (from age 21 years) up to age 30, 35, 40, or 45 years. The models were empirically calibrated to reflect the burden of HPV and related cancers in the US population and used standardized inputs regarding historical and future vaccination uptake, vaccine efficacy, cervical cancer screening, and costs. Disease outcomes included cervical, anal, oropharyngeal, vulvar, vaginal, and penile cancers, as well as genital warts. Both models projected higher costs and greater health benefits as the upper age limit of HPV vaccination increased. Strategies of vaccinating females and males up to ages 30, 35, and 40 years were found to be less cost-effective than vaccinating up to age 45 years, which had an incremental cost-effectiveness ratio (ICER) greater than a commonly accepted upper threshold of $200,000 per quality-adjusted life year (QALY) gained. When including all HPV-related outcomes, the ICER for vaccinating up to age 45 years ranged from $315,700 to $440,600 per QALY gained. Assumptions regarding cervical screening compliance, vaccine costs, and the natural history of noncervical HPV-related cancers had major impacts on the cost-effectiveness of the vaccination strategies. Key limitations of the study were related to uncertainties in the data used to inform the models, including the timing of vaccine impact on noncervical cancers and vaccine efficacy at older ages.ConclusionsOur results from 2 independent models suggest that HPV vaccination for adult women and men aged 30 to 45 years is unlikely to represent good value for money in the US.Jane Kim and co-workers estimate the potential cost-effectiveness of papillomavirus vaccination for adults aged 30-45 years in the United States. 相似文献
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424.
Optically active lumazines (biolumazine, dictyolumazine, monalumazine, and neolumazine) are prepared from the corresponding pterins by enzymatic reaction, using pterin deaminase excreted by Dictyostelium discoideum. The fluorescence properties, circular dichroism spectra, and chromatographic behavior of these lumazines are studied. D - and L -enantiomers of biolumazine, dictyolumazine, and monalumazine are separated using a chiral flavoprotein column. This column also separates the enantiomeric pterins of the threo form: monapterin and dictyopterin. However, the column does not separate the enantiomeric pterins of the erythro form: neopterin and biopterin. By coupling a reverse-phase column to the flavoprotein column, the separation of pterins and lumazines in function of their hydrophobicity, as well as the separation of the diastereomers, is achieved. This coupled achiral/chiral high-performance liquid chromatography method enables determination of the stereoconfiguration of natural lumazines by comparison with optically pure compounds. A lumazine derivative, present in the extracellular medium of Dictyostelium discoideum, is identified as D -dictyolumazine, i.e., 6-(D -threo-1,2-dihydroxypropyl)-lumazine. © 1994 Wiley-Liss, Inc. 相似文献
425.
Kerstin Brinkmann Paul Waring Stefan P Glaser Verena Wimmer Denny L Cottle Ming Shen Tham Duong Nhu Lachlan Whitehead Alex RD Delbridge Guillaume Lessene Ian M Smyth Marco J Herold Gemma L Kelly Stephanie Grabow Andreas Strasser 《The EMBO journal》2020,39(24)
Studies of gene‐targeted mice identified the roles of the different pro‐survival BCL‐2 proteins during embryogenesis. However, little is known about the role(s) of these proteins in adults in response to cytotoxic stresses, such as treatment with anti‐cancer agents. We investigated the role of BCL‐XL in adult mice using a strategy where prior bone marrow transplantation allowed for loss of BCL‐XL exclusively in non‐hematopoietic tissues to prevent anemia caused by BCL‐XL deficiency in erythroid cells. Unexpectedly, the combination of total body γ‐irradiation (TBI) and genetic loss of Bcl‐x caused secondary anemia resulting from chronic renal failure due to apoptosis of renal tubular epithelium with secondary obstructive nephropathy. These findings identify a critical protective role of BCL‐XL in the adult kidney and inform on the use of BCL‐XL inhibitors in combination with DNA damage‐inducing drugs for cancer therapy. Encouragingly, the combination of DNA damage‐inducing anti‐cancer therapy plus a BCL‐XL inhibitor could be tolerated in mice, at least when applied sequentially. 相似文献
426.
Lauric acid alleviates insulin resistance by improving mitochondrial biogenesis in THP-1 macrophages
Tham Yong Yao Choo Quok Cheong Muhammad Tengku Sifzizul Tengku Chew Choy Hoong 《Molecular biology reports》2020,47(12):9595-9607
Molecular Biology Reports - Mitochondrial dysfunction plays a crucial role in the central pathogenesis of insulin resistance and type 2 diabetes mellitus. Macrophages play important roles in the... 相似文献
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428.
A ribosome-independent guanosine 5',3'-polyphosphate synthetase has been highly purified from Bacillus brevis (ATCC 8185). The enzyme has a molecular weight of 55,000, as measured by sucrose density gradient centrifugation. Like the ribosome-connected stringent factor of Escherichia coli, it catalyzes the synthesis of the guanosine 5', 3'-polyphosphates by a pyrophosphoryl transfer mechanism from adenosine triphosphate (ATP) to guanosine di- or triphosphates (GDP, GTP). It has an apparent Km of 0.14 mM for GDP and 0.77 mM for GTP, and is specific for the guanosine ribonucleotides as pyrophosphoryl acceptors. Several ATP analogues were tested for their ability to donate the pyrophosphoryl group. Mg2+ was required as a counter ion for the nucleotide substrate; however, an excess of Mg2+ was inhibitory. The property of the B. brevis enzyme is compared with the ribosome-linked enzyme of E. coli and an extracellular enzyme excreted by several types of Streptomyces reported upon recently. 相似文献
429.
Plasmodium vivax is responsible for most of the malaria infections outside Africa and is currently the predominant malaria parasite in countries under elimination programs. P. vivax preferentially enters young red cells called reticulocytes. Advances in understanding the molecular and cellular mechanisms of entry are hampered by the inability to grow large numbers of P. vivax parasites in a long‐term in vitro culture. Recent progress in understanding the biology of the P. vivax Reticulocyte Binding Protein (PvRBPs) family of invasion ligands has led to the identification of a new invasion pathway into reticulocytes, an understanding of their structural architecture and PvRBPs as targets of the protective immune response to P. vivax infection. This review summarises current knowledge on the role of reticulocytes in P. vivax infection, the function of the PvRBP family of proteins in generating an immune response in human populations, and the characterization of anti‐PvRBP antibodies in blocking parasite invasion. 相似文献
430.
Mechanisms of regulation of cell-mediated immunity. VI. Antigen density dependence of the induction of genetically restricted suppressor cells 总被引:1,自引:0,他引:1
A Pierres J S Bromberg M S Sy B Benacerraf M I Greene 《Journal of immunology (Baltimore, Md. : 1950)》1980,124(1):343-348
We have investigated the relationship of antigen density on cell surfaces to the induction of genetically restricted suppressor T cells (Ts). It was found that Ts able to suppress the development of hapten-specific contact sensitivity were induced by the i.v. inoculation of trinitrobenzene sulfonate (TNBS) hapten-coupled cells. The Ts induced by this technique were found to be gentically unrestricted in terms of generation or expression when 10 mM TNBS were used to prepare the hapten-coupled cells. Transferable suppression could be obtained by 10 mM coupled allogeneic cells or, alternatively, TNP-coupled Ia- syngeneic erythrocytes or even H-2-negative syngeneic tumor cells. However, 1 mM TNBS-derivatized hapten-coupled cells induced Ts that were able to suppress only recipients syngeneic with the tolerogen. The significance of these findings to our understanding of the induction and expression of Ts and the triggering signals that are necessary for their activation are discussed. 相似文献