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AIDS and associated malignancies

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Cell Research 2005年第Z1期15卷 947-952页

作者： Charles WOOD William HARRINGTON jr Nebraska Center for Virology & School of Biological Sciences University of Nebraska Lincoln NE 68588 USA Sylvester Cancer Center University of Miami Miami FL 33136 USA

AIDS associated malignancies (ARL) is a major complication associated with AIDS patients upon immunosuppression. Chronically immunocompromised patients have a markedly increased risk of developing lymphoproliferative disease. In the era of potent antiretrovirals therapy (ARV), the malignant complications due to HIV-1 infection have decreased in developed nations where ARV is administered, but still poses a major problem in developing countries where HIV-1 incidence is high and ARV is still not yet widely available. Even in ARV treated individuals there is a concern that the prolonged survival of many HIV-1 carriers is likely to eventually result in an increased number of malignancies diagnosed. Malignancies that were found to have high incidence in HIV-infected individuals are Kaposi’s sarcoma (KS), Hodgkin’s disease (HD) and non-Hodgkin’s lymphoma (NHL). The incidence of NHL has increased nearly 200 fold in HIV-positive patients, and accounts for a greater percentage of AIDS defining illness in the US and Europe since the advent of HAART therapy. These AIDS related lymphomas are distinct from their counterparts seen in HIV-1 seronegative patients. For example nearly half of all cases of ARL are associated with the presence of a gamma herpesvirus, Epstein Barr virus (EBV) or human herpesvirus-8 (HHV-8)/ Kaposi’s sarcoma associated herpesvirus (KSHV). The pathogenesis of ARLs is complex. B-cell proliferation driven by chronic antigenemia resulting in the induction of polyclonal and ultimately monoclonal lymphoproliferation may occur in the setting of severe immunosuppression.

关键词： Kaposi’s sarcoma lymphomas Epstein-Barr virus KS-associated herpesvirus human herpesvirus 8.

Deformation‑Induced Strengthening Mechanism in a Newly Designed L‑40 Tool Steel Manufactured by Laser Powder Bed Fusion

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Acta Metallurgica Sinica(English Letters) 2023年第1期36卷 21-34页

作者： Yuan Tian Kanwal Chadha Clodualdo Aranas jr Voestalpine Additive Manufacturing Centre Ltd MississaugaON L5N 7Y3Canada Department of Mechanical Engineering University of New BrunswickFrederictonNB E3B 5A3Canada Planetary and Space Science Centre University of New BrunswickFrederictonNB E3B 5A3Canada

The microstructural and mechanical properties of a newly designed tool steel(L-40),specifcally designed to be employed in the laser powder bed fusion(LPBF)technique,were *** pool boundaries with submicron dendritic structures and about 14%retained austenite phase were evident after *** grain orientation after high cooling rate solidifcation is mostlyα∥building direction(BD).Then,the heat treatment converted the microstructure into a conventional martensitic phase,reduced the retained austenite to about 1.5%,and increasedα∥BD *** heat-treated sample exhibits higher tensile strength(1720±14 MPa)compared to the as-printed sample(1540±26 MPa)along the building direction,mainly due to hardening caused by a lower volume fraction of retained austenite phase and precipitation of *** a consequence of the strength-to-ductility trade-of,the heat-treated sample showed lower elongation(10%±2%)than that of the as-printed sample(18%±2%).It was observed that transformation-induced plasticity(TRIP)occurs in both the as-printed and heat-treated samples during tensile testing,which dynamically transforms the retained austenite into martensite,leading to improved *** minimum driving force to initiate the displacive phase transformation is about 6000 J/mol,which was achieved during tensile *** strength and ductility of LPBF-produced L-40 were compared with the other LPBF-produced tool steels in literature;the data indicate that heat-treated L-40 has an excellent combination of strength and ductility complemented with high printability.

关键词： Additive manufacturing Laser powder bed fusion L-40 tool steel Phase transformation

Dietary free fatty acids complex with amylose creating another form of resistant starch: Gastrointestinal formation with fowl and swine

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Animal Nutrition 2021年第4期7卷 1124-1132页

作者： Edwin T.Moran jr. Poultry Science Department Auburn UniversityAL36849-5416USA

Fat added to poultry and swine feeds often contains abundant free fatty acids(FFA)that can impair digestible energy(DE).Placement of the fatty acid(FA)hydrocarbon chain in the helix core reformed from amylose creates a complex of both *** modifications create a new structure termed the V-helix that becomes resistant toα-*** in grain naturally contain minimal amounts of these complexes with more being generated during food manufacturing when moisture and heat release amylose in the presence of FFA.A paucity of FFA usually exists in complete feeds without sources of poorquality *** fats and by-product meals from rendering are prominent in their saturated FFA content which favorably complex within the helix.V-helix-FA complexes may arise during their concurrent encounter of FFA together with amylose during feed manufacture,particularly *** in the gastrointestinal tract(GIT)are speculated to further form complexes when present together with *** amylose may be dissolved in the gastric and small intestinal milieu,FFA separately coalesce into hydrophobic fat droplets along with other dietary *** of complexes is likely restricted until FFA are released into the aqueous phase during fat ***α-amylase may be prominent,V-helix-FA complexes being resistant to enzymic attack pass into the large *** microbial catabolism of V-helices may generate volatile fatty acids that are absorbed by the mucosa;however,an inability to use FFA once released leads to their excretion and basis for decreased *** microbial populations with young animals usually lack the capacity to fully catabolize the V-helix,further extending the loss in DE.

关键词： Amylose Digestible energy Free fatty acid Feed manufacture

Implication of altered proteasome function in alcoholic liverinjury

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World Journal of Gastroenterology 2007年第37期13卷 4931-4937页

作者： Natalia A Osna Terrence M Donohue jr Liver Study Unit The Omaha Veterans Affairs Medical Center the Department of Internal Medicine University of Nebraska Medical Center Omaha Nebraska 68105 United States

The proteasome is a major protein-degrading enzyme, which catalyzes degradation of oxidized and aged proteins, signal transduction factors and cleaves peptides for antigen presentation. Proteasome exists in the equilibrium of 26S and 20S particles. Proteasome function is altered by ethanol metabolism, depending on oxidative stress levels： low oxidative stress induces proteasome activity, while high oxidative stress reduces it. The proposed mechanisms for modulation of proteasome activity are related to oxidative modification of proteasomal proteins with primary and secondary products derived from ethanol oxidation. Decreased proteolysis by the proteasome results in the accumulation of insoluble protein aggregates, which cannot be degraded by proteasome and which further inhibit proteasome function. Mallory bodies, a common signature of alcoholic liver diseases, are formed by liver cells, when proteasome is unable to remove cytokeratins. Proteasome inhibition by ethanol also promotes the accumulation of pro-apoptotic factors in mitochondria of ethanol-metabolizing liver cells that are normally degraded by proteasome. In addition, decreased proteasome function also induces accumulation of the negative regulators of cytokine signaling （I-~B and SOCS）, thereby blocking cytokine signal transduction. Finally, ethanol-elicited blockade of interferon type 2 and 2 signaling and decreased proteasome function impairs generation of peptides for MHC class Ⅰ-restricted antigen presentation.

关键词： 20S proteasome 26S proteasome, PA28, CYP2E1, Apoptosis, Liver

Theory and application of cyclic voltammetry for measurement of fast electrode kinetics at microdisk electrode

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Chinese Journal of Chemistry 1996年第4期14卷 338-347页

作者： Jin, BK Zhang, jr Zhang, ZX NANJING UNIV DEPT CHEMNANJING 210093JIANGSUPEOPLES R CHINA

An analytical expression describing voltammetric behaviors responses at microdisk electrode for various diffusion conditions and degrees of reversibility is reported in this paper. Results of theoretical calculation made it possible to use cyclic voltammetry to evaluate heterogeneous rate constants under intermediate diffusion conditions. At relatively low scan rate, the distortion of current-voltage can be reduced due to small iR drops and charging current. The effects of transfer coefficient, alpha, kinetic parameter, lambda(=k(0)r/4D), and switching potential, xi(8), on potential peak separation are discussed in detail. The relationship obtained in this paper between potential peak separation and lambda is in good agreement with that in Ref. 14, whose authors have got their results by using digital simulation technique. After the experiment of Fe(CN)(6)(4-) oxidation, k(0) and alpha were obtained by the theory of this paper. The result agrees with that in Ref. 19.

关键词： microdisk electrode kinetics cyclic voltammetry

Numerical Approach to Film Cooling Effectiveness Over a Plate Surface with Coolant Impingement

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Journal of Thermal Science 2004年第1期13卷 67-74页

作者： Chang-Hsien Tai jr-Ming Miao A-Fu Kao Department of Vehicles Engineering National Pingtung University of Science and TechnologyPingtungTaiwanChinaDepartment of Mechanical EngineeringChung Cheng Institute of TechnologyNational Defense UniversityTaoyuanTaiwanChinaGraduate School of Defense Science StudiesChung Cheng Institute of TechnologyNational Defense UniversityTaoyuanTaiwanChina

The aim of the present study is conducting the numerical approach to a combination of internal jet impingement and external film cooling over a flat plate. A multi-block three-dimensional Navier-Stokes code, CFX 4.4, with k-e turbulence model is used to simulate this complicated thermal-flow structure induced by the interaction of coolant jet and hot cross mainstream. By assuming the adiabatic wall boundary condition on the tested film-cooled plate, both the local and the spanwise-averaged adiabatic film cooling effectiveness are evaluated for comparison of the cooling performance at blowing ratios of Br=0.5, 1.0, and 1.5. Film flow data were obtained from a row of five cylindrical film cooling holes, inclined in angle of 35?and 0?in direction of streamwise and spanwise, respectively. The film cooling hole spacing between adjacent holes is 15 mm for all the holes. Before the coolant flow being injected through individual cooling hole then encountered with the mainstream, an impingement chamber containing an impingement plate with 43 holes is located on the path of coolant flow. Present study also focused on the effect of impingement spacing, 10mm, 20mm, and 30mm. Compare the results, we find the impingement jet has a significant effect on the adiabatic film cooling effectiveness. As the coolant impingement spacing is fixed, results indicated that higher blowing ratio would enhance the local and the spanwise-averaged adiabatic film cooling effectiveness. Moreover, neither uniform nor parabolic distribution of pressure distribution are observed within the coolant hole-pipe.

关键词： film cooling impingement cooling CFD turbulence model.

Effect of in-situ formed Al hydrates through long-term aging on enhanced particle destabilization by PACl coagulation

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Journal of Environmental Sciences 2020年第6期32卷 200-210页

作者： jr Lin Lin Aldeno Rachmad Ika Chun Chen Tseng Department of Environmental Engineering Chung Yuan Christian UniversityChinese Taipei

Aging of polyaluminum chloride(PACl) coagulants could significantly influence hydrolyzed Al speciation ruling coagulation *** goal of this study was to investigate Al species transformation through long-term aging and its impact on coagulation *** kinds of commercial coagulants(PACl-1 and PACl-2) were stored for in-situ aging tests in six months to evaluate Al species variation with time and the performance of coagulation with natural turbid *** results showed that CaSO4 precipitation easily occur in a commercial PACl coagulant with time as it contains SO4^2- and Ca^2+.It also activates the precipitation of gibbsite Al(OH)3 in PACl with *** 180 days aging,both monomeric Al(Ala) and polymeric Al(Alb) substantially transform into colloidal Al(Alc) and precipitated for both PACl *** low turbidity(10 NTU),PACl-1 has a superior turbidity reduction rate than PACl-2,while PACl-2 performs a little better turbidity re duction at high turbidity(1000 NTU) regardless of aging *** aging time,an obvious decrease in turbidity reduction for PACl-1 coagulation is observed at low turbidity of 10 NTU,while the improvement in turbidity reduction for PACl-2 coagulation by enhanced sweep flocculation can be achieved as Alb mostly transform into Alc after 150 days *** is concluded that dominant in-situ formed Alc after a long time hydrolysis can improve PACl coagulation efficiency in turbidity reduction by enhanced sweep flocculation,especially for low turbidity water,but the increase in preformed Alc in PACl would worsen particle destabilization after aging.

关键词： Coagulation PACl Aging Al hydrates

Review of endoscopic techniques in the diagnosis and management of cholangiocarcinoma

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World Journal of Gastroenterology 2008年第19期14卷 2995-2999页

作者： Katherine Nguyen James T Sing jr Scott & White Clinic Texas A&M University Health Science Center College of Medicine

Cholangiocarcinoma is a rare malignancy of the biliary tract. Key factors in determining therapeutic options include knowledge of tumor extent, anatomy and obtaining tissue diagnosis. Endoscopically, there are three modalities available to make the diagnosis of cholangiocarcinoma. These include endoscopic retrograde cholangiopancreatography, endoscopic ultrasound with fine needle aspiration and cholangioscopy. Management of cholangiocarcinoma endoscopically is typically confined to stent placement for palliative purposes or as a bridge to surgery. In this article, we will review the endoscopic techniques available for the diagnosis and management of cholangiocarcinoma.

关键词： Cholangiocarcinoma Endoscopic ultrasound Endoscopic cholangiopancreatography Cholangioscopy Diagnosis Hanagement

Polymer-virus core-shell structures prepared via co-assembly and template synthesis methods

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Science China Chemistry 2010年第1期53卷 71-77页

作者： SUTHIWANGCHAROEN Nisaraporn PREVELIGE Peter E.jr Department of Chemistry and Biochemistry and Nanocenter University of South CarolinaColumbiaSouth Carolina 29208USA Department of Microbiology University of Alabama at BirminghamBirminghamAL 35294USA

Bionanoparticles(BNPs),consisting of virus and virus-like assemblies,have attracted much attention in the biomedical field for their applications such as imaging and targeted drug delivery,owing to their well-defined structures and well-controlled ***-based core-shell structures provide a unique system for the investigation of biological interactions such as protein-protein and protein-carbohydrate ***,it is still a challenge to prepare the BNPs-based core-shell ***,we describe(i) co-assembly method and(ii) template synthesis method in the development of polymer-BNPs core-shell *** two methods can be divided into three different *** system A,different polymers including poly(2-vinylpyridine)(P2VP),poly(4-vinylpyridine)(P4VP) and poly(ε-caprolactone)-block-poly(2-vinylpyridine)(PCL-b-P2VP) can form a raspberry-like structure with *** system B,polystyrene(PS) spheres end capped with free amine and BNPs can form a core-shell *** System C,layer-by-layer(LBL) method is used to prepare positive charged PS particles,which can be used as a template to form the core-shell structures with *** two methods may open a new way for preparing novel protein-based functional materials for potential applications in the biomedical field.

关键词： core-shell structures bionanoparticles virus polymers co-assembly template synthesis layer-by-layer