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Biodegradable magnesium materials regulate ROS-RNS balance in pro-inflammatory macrophage environment

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Bioactive Materials 2023年第5期23卷 261-273页

作者： Maria P.Kwesiga Amani A.Gillette Fatemeh Razaviamri Margaret e.Plank Alexia L.Canull Zachary Alesch Weilue He bruce P.Lee Roger J.Guillory II Department of Biomedical engineering Michigan Technological UniversityHoughtonMIUSA Morgridge Institute for Research MadisonWIUSA Department of Biomedical engineering University of Wisconsin-MadisonMadisonWIUSA

The relationship between reactive oxygen and nitrogen species(ROS-RNS)secretion and the concomitant biocorrosion of degradable magnesium(Mg)materials is poorly *** found that Mg foils implanted short term in vivo(24 h)displayed large amounts of proinflammatory F4/80+/iNOS+macrophages at the *** sought to investigate the interplay between biodegrading Mg materials(98.6%Mg,AZ31&AZ61)and macrophages(RAW 264.7)stimulated with lipopolysaccharide(RAW 264.7^(LPS))to induce ROS-RNS *** test how these proinflammatory ROS-RNS secreting cells interact with Mg corrosion in vitro,Mg and AZ61 discs were suspended approximately 2 mm above a monolayer of RAW 264.7 cells,either with or without ^(LPS).The surfaces of both materials showed acute(24 h)changes when incubated in the proinflammatory RAW 264.7^(LPS) *** discs incubated with RAW 264.7^(LPS) macrophages showed greater corrosion pitting,while AZ61 showed morphological and elemental bulk product changes via scanning electron microscopy-energy dispersive X-ray spectroscopy(SeM-eDX).X-ray photoelectron spectroscopy(XPS)analysis showed a reduction in the Ca/P ratio of the surface products for AZ61 disc incubated with RAW 264.7^(LPS),but not the Mg ***,RAW 264.7^(LPS) macrophages were found to be more viable in the acute biodegradative environment generated by Mg materials,as demonstrated by calcein-AM and cleaved(active)caspase-3 staining(CC3).^(LPS) stimulation caused an increase in ROS-RNS,and a decrease in antioxidant peroxidase *** and AZ61 were found to change this ROS-RNS balance,independently of physiological antioxidant *** findings highlight the complexity of the cellular driven acute inflammatory responses to different biodegradable Mg,and how it can potentially affect performance of these materials.

关键词： Biocorrosion Macrophage activation Nitroso-redox balance Mg

Nested Metal Catalysts:Metal Atoms and Clusters Stabilized by Confinement with Accessibility on Supports

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Precision Chemistry 2023年第1期1卷 3-13页

作者： bruce C.Gates Alexander Katz Jingyue Liu Department of Chemical engineering University of CaliforniaDavisDavisCalifornia 95616United States Department of Chemical and Biomolecular engineering University of CaliforniaBerkeleyBerkeleyCalifornia 94720United States Department of Physics Arizona State UniversityTempeArizona 85287United States

Supported catalysts that are important in technology prominently include atomically dispersed metals and metal *** the metals are noble,they are typically unstablesusceptible to sinteringespecially under reducing *** the metals in supports such as organic polymers,metal oxides,and zeolites confers stability on the metals but at the cost of catalytic activity associated with the lack of accessibility of metal bonding sites to *** approach to stabilizing noble metal catalysts while maintaining their accessibility involves anchoring them in molecular-scale nests that are in or on *** nests include zeolite pore mouths,zeolite surface cups(half-cages),raft-like islands of oxophilic metals bonded to metal oxide supports,clusters of non-noble metals(e.g.,hosting noble metals as single-atom alloys),and nanoscale metal oxide islands that selectively bond to the catalytic metals,isolating them from the *** examples illustrate a trend toward precision in the synthesis of solid catalysts,and the latter two classes of nested catalysts offer realistic prospects for economical large-scale application.

关键词： catalyst synthesis supported metal catalysts encapsulated catalysts nested catalysts atomically dispersed metal catalysts

Physician approaches to drug shortages: Results of a national survey of pediatric hematologist/oncologists

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World Journal of Clinical Oncology 2017年第4期8卷 336-342页

作者： Jill C Beck Baojiang Chen bruce G Gordon Department of Pediatric Hematology/Oncology University of Nebraska Medical Center

AIM To evaluate personnel involved in scarce drug prioritization and distribution and the criteria used to inform drug distribution during times of shortage among pediatric hematologists/oncologists. MeTHODS Using the American Society of Pediatric Hematology/Oncology(ASPHO) membership list, a 20 question survey of pediatric hematologists/oncologists was conducted via email to evaluate personnel involved in scarce drug prioritization and distribution and criteria used to inform scarce drug distribution. ReSULTS Nearly 65% of the 191 study respondents had patients directly affected by drug shortages. Most physicians find out about shortages from the pharmacist(n = 179, 98%) or other doctors(n = 75, 41%). One third of respondents do not know if there is a program or policy for handling drug shortages at their institution. The pharmacist was the most commonly cited decision maker for shortage drug distribution(n = 128, 70%), followed by physicians(n = 109, 60%). One fourth of respondents did not know who makes decisions about shortage drug distribution at their institution. The highest priority criterion among respondents was use of the shortage drug for curative, rather than palliative intent and lowest priority criterion was order of arrival or first-come *** Despite pediatric hematology/oncology physicians and patients being heavily impacted by drug shortages, institutional processes for handling shortages are lacking. There is significant disparity between how decisions for distribution of shortage drugs are currently made and how study respondents felt those decisions should be made. An institution-based, and more importantly, a societalapproach to drug shortages is necessary to reconcile these disparities.

关键词： Pediatric hematology/oncology Chemotherapy ethics

Immune Regulatory Cell Biology and Clinical Applications to Prevent or Treat Acute Graft-Versus-Host Disease

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engineering 2019年第1期5卷 98-105页

作者： bruce R. Blazar Masonic Cancer Center & Division of Blood and Marrow Transplantation Department of Pediatrics University of Minnesota Minneapolis MN 55455 USA

The most common approaches to prevent and treat graft-versus-host disease (GVHD) are intended to deplete or suppress the T cells capable of mediating or supporting alloresponses;however, this renders the recipients functionally T cell deficient and hence highly susceptible to infections and tumor recurrence. Depletion is often accomplished through the use of broadly reactive antibodies, while functional impairment is typically achieved by pharmacological agents that require long-term administration (usually six months or more), have significant side effects, and may not result in tolerance (i.e., nonresponsiveness) of donor T cells to conditioning regimen-resistant host alloantigen-bearing cells. As our knowledge of immune system homeostasis has increased, cell populations with immune regulatory function have been identified and characterized. Although such cell populations are typically present in low frequencies, methods to isolate and expand these cells have permitted their supplementation to the donor graft or infusion late post-transplant in order to stifle GVHD. This review discusses the biology and preclinical proof of concept of GVHD models, along with GVHD outcomes that focus exclusively on immune regulatory cell therapies that have progressed to clinical testing.

关键词： Graft-versus-host disease (GVHD) Immune regulatory cells Cell therapy

Congenital diaphragmatic hernia survival in an english regional eCMO center

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World Journal of Pediatric Surgery 2023年第2期6卷 77-84页

作者： elizabeth O'connor Ryo Tamura Therese Hannon Sundeep Harigopal bruce Jaffray Paediatric surgery The Great North Children's HospitalNewcastle upon TyneTyne&WearUK Fetal medicine and obstetrics Royal Victoria InfirmaryNewcastle upon TyneTyne&WearUK Neonatal medicine Royal Victoria InfirmaryNewcastle upon TyneTyne&WearUK

Introduction Congenital diaphragmatic hernia(CDH)remains a cause of neonatal *** aims are to describe contemporary rates of survival and the variables associated with this outcome,contrasting these with our study of two decades earlier and recent *** and methods A retrospective review of all infants diagnosed in a regional center between January 2000 and December 2020 was *** outcome of interest was *** explanatory variables included side of defect,use of complex ventilatory or hemodynamic strategies(inhaled nitric oxide(iNO),high-frequency oscillatory ventilation(HFOV),extracorporeal membrane oxygenation(eCMO),and Prostin),presence of antenatal diagnosis,associated anomalies,birth weight,and *** changes were studied by measuring outcomes in each of four consecutive 63-month *** A total of 225 cases were *** was 60%(134 of 225).Postnatal survival was 68%(134 of 198 liveborn),and postrepair survival was 84%(134 of 159 who survived to repair).Diagnosis was made antenatally in 66%of *** associated with mortality were the need for complex ventilatory strategies(iNO,HFOV,Prostin,and eCMO),antenatal diagnosis,right-sided defects,use of patch repair,associated anomalies,birth weight,and *** has improved from our report of a prior decade and did not vary during the study *** survival has improved despite fewer *** multivariate analysis,the need for complex ventilation was the strongest predictor of death(OR=50,95%CI 13 to 224,ped anomalies ceased to be *** Survival has improved from our earlier report,despite reduced numbers of *** may be related to increased use of complex ventilatory strategies.

关键词： Survival termination sided

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可烧结硬化组成合金的开发

粉末冶金技术 2011年第3期29卷 232-235页

作者： bruce Lindsley Hoeganaes公司 Cinnaminson美国NJ 08077

粉末冶金产业市场力量正在挑战粉末冶金合金中通常使用的传统组成。Mo、Ni及Cu因和氧亲和力低,是铁基粉末冶金使用的主要合金化元素。另外,Mo对压缩性的影响很小,和Cu在烧结温度下通过液相可快速熔成合金。这三种元素也都增高钢的淬透性... 详细信息

粉末冶金产业市场力量正在挑战粉末冶金合金中通常使用的传统组成。Mo、Ni及Cu因和氧亲和力低,是铁基粉末冶金使用的主要合金化元素。另外,Mo对压缩性的影响很小,和Cu在烧结温度下通过液相可快速熔成合金。这三种元素也都增高钢的淬透性,用这些元素的混合物生产的零件可进行烧结硬化。价格压力迫使对采用这些元素的粉末组成重新进行了评估,合金开发的任务在于提出使力学性能与生产总成本间达到最佳平衡的合金系。烧结硬化合金组成在这一点上起重要作用。将评估与讨论可替代在欧洲市场上主要使用的合金的合金。

关键词：烧结硬化合金组成开发

Pt-CeO_2/SiO_2 catalyst for CO oxidation in humid air at ambient temperature

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Chinese Journal of Catalysis 2017年第3期38卷 475-488页

作者： Shirish S.Punde bruce J.Tatarchuk 奥本大学化学工程系美国亚拉巴马州奥本市

CO self-poisoning and slow surface kinetics pose major challenges to a CO oxidation catalyst that should work at ambient ***,the presence of moisture would cause passivation of the catalyst A highly active ceria promoted Pt catalyst（4%Pt-12%CeO_2/SiO_2;conversion≥99%at low（ 500 ppm） and high（ 2500 ppm） CO concentrations was developed for CO oxidation at ambient temperature in humid *** preparation variables such as Pt and CeO_2 loading,ceria deposition method,drying and calcination conditions for the ceria and Pt precursors were optimized *** activity was correlated with surface properties using CO/H_2 chemisorption,O_2-H_2 titration,X-ray diffraction and BeT surface area *** method of CeO_2 deposition had a significant impact on the catalytic ***_2 deposition by impregnation resulted in a catalyst that was three times more active than that prepared by deposition precipitation or CeO_2grafting.O_2-H_2 titration results revealed that the close association of ceria and Pt in the case of CeO_2deposition by impregnation resulted in higher *** catalyst support used was also crucial as a silica supported catalyst was five times more active than an alumina supported *** particle size and pore structure of the catalyst support were also crucial as the reaction was diffusion *** drying and calcination conditions of the ceria and Pt precursors also played a crucial role in determining the catalytic *** Pt-CeO_2/SiO_2 catalysts with Pt 2.5 wt%and CeO_2 15 wt%were highly active（TOF 0.02 s^（-1）） and stable（conversion 99%after 15 h） at ambient conditions.

关键词： Carbon monoxide oxidation Catalyst Platium Ceria Silica Precursor O_2-H_2 titration Chemisorption Temperature-programmed reduction

Tyrosine metabolic enzymes from insects and mammals：A comparative perspective

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Insect Science 2014年第1期21卷 13-19页

作者： Christopher John Vavricka Qian Han Prajwalini Mehere Haizhen Ding bruce M. Christensen and Jianyong Li Research Network of Immunity and Health (RNIH) Beijing Institutes of Life Science Chinese Academy of Sciences BeUing China Department of Biochemistry Virginia Polytechnic and State University Blacksburg VA 24061 USA Department of Tuberculosis The Foundation for Medical Research Mumbai India and Department of Pathobiology University of Wisconsin-Madison Madison Wl 53706 USA

Differences in the metabolism of tyrosine between insects and mammals present an interesting example of molecular evolution. Both insects and mammals possess finetuned systems of enzymes to meet their specific demands for tyrosine metabolites; however, more homologous enzymes involved in tyrosine metabolism have emerged in many insect species. Without knowledge of modem genomics, one might suppose that mammals, which are generally more complex than insects and require tyrosine as a precur sor for important catecholamine neurotransmitters and for melanin, should possess more enzymes to control tyrosine metabolism. Therefore, the question of why insects actually possess more tyrosine metabolic enzymes is quite interesting. It has long been known that insects rely heavily on tyrosine metabolism for cuticle hardening and for innate immune responses, and these evolutionary constraints are likely the key answers to this question. In terms of melanogenesis, mammals also possess a high level of regulation; yet mam malian systems possess more mechanisms for detoxification whereas insects accelerate pathways like melanogenesis and therefore must bear increased oxidative pressure. Our research group has had the opportunity to characterize the structure and function of many key proteins involved in tyrosine metabolism from both insects and mammals. In this mini review we will give a brief overview of our research on tyrosine metabolic enzymes in the scope of an evolutionary perspective of mammals in comparison to insects.

关键词： arylalkylamine N-acetyltransferase (aaNAT) enzymology L-DOPAdecarboxylase (DDC) melanogenesis tyrosine metabolism

Novel vertically aligned nanocomposite of Bi_(2)WO_(6)-Co_(3)O_(4) with room-temperature multiferroic and anisotropic optical response

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Nano Research 2021年第12期14卷 4789-4794页

作者： Leigang Li Shikhar Misra Xingyao Gao Juncheng Liu Han Wang Jijie Huang bruce Zhang Ping Lu Haiyan Wang School of Materials engineering Purdue UniversityWest LafayetteIndiana47907USA School of electrical and Computer engineering Purdue UniversityWest LafayetteIndiana47907USA Sandia National Laboratory AlbuquerqueNew Mexico87185USA

A new vertically aligned nanocomposite(VAN)structure based on two-dimensional(2D)layered oxides has been designed and self-assembled on both LaAlO_(3)(001)and SrTiO3(001)*** new VAN structure consists of epitaxially grown Co_(3)O_(4) nanopillars embedded in the Bi_(2)WO_(6) matrix with a unique 2D layered structure,as evidenced by the microstructural *** property measurements show that the new Bi_(2)WO_(6)-Co_(3)O_(4) VAN structure exhibits strong ferromagnetic and piezoelectric response at room temperature as well as anisotropic permittivity *** work demonstrates a new approach in processing multifunctional VANs structure based on the layered oxide systems towards future nonlinear optics,ferromagnets,and multiferroics.

关键词： vertically aligned nanocomposite(VAN) multiferroics Aurivillius oxides layered oxides Co_(3)O_(4) Bi_(2)WO_(6)