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Evaluation of the new OxyPlate^(TM) Anaerobic System for the isolation of ocular anaerobic bacteria

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International Journal of Ophthalmology(English edition) 2012年第5期5卷 582-585页

作者： Emily k. Deschler paul P. Thompson Regis paul kowalski Department of Ophthalmology University of Pittsburgh 203 Lothrop Street Ophthalmic Microbiology The Eye & Ear InstitutePittsburgh Pennsylvania 15213 United States

AIM: Anaerobic bacteria can cause ocular infections. We tested the OxyPlateTM Anaerobic System (OXY) to isolate pertinent anaerobic bacteria that can cause ocular ***: OXY, which does not require direct anaerobic conditions (i.e. bags, jars), was compared to conventional isolation of incubating culture media in anaerobic bags. Standard colonies counts were performed on anaerobic ocular bacterial isolates under aerobic and anaerobic conditions (anaerobic bags) using agar media: 1) OXY (aerobic only), 2) 5% sheep blood (SB), 3) Chocolate, and 4) Schaedler. The bacteria tested were de-identified ocular isolates cultured from endophthalmitis and dacryocystitis that include 10 Propionibacterium acnes and 3 Actinomyces species. The colony counts for each bacteria isolate, on each culturing condition, were ranked from largest to smallest, and non-parametrically compared to determine the best culturing ***: All anaerobic conditions were positive for all of the anaerobic isolates. SB and Schaedler’s agar under aerobic conditions did not support the growth of anaerobic bacteria. Sparse growth was noted on chocolate agar with Propionibacterium acnes . As an anaerobic system, SB in an anaerobic bag isolated higher colony counts than OXY (P=0.0028) and chocolate agar (P=0.0028).CONCLUSION: Although OXY did not test to be more efficient than other anaerobic systems, it appears to be a reasonable alternative for isolating anaerobic bacteria from ocular sites. The use of an agar medium in a specially designed plate, without the requirement of an anaerobic bag, rendered OXY as an advantage over other anaerobic systems.

关键词： anaerobic bacteria bacterial isolation endophthalmitis dacryocystitis

Spatial Potential Distribution around Trench Target during Plasma Immersion Ion Implantation

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Journal of Materials Science & Technology 2003年第z1期19卷 94-96页

作者： Xiubo Tian Chunbei Wei Shiqin Yang paul k. Chu Ricky k.Y. Fu State key Lab. of Welding Production Technology School of Mater. Sci. & Eng. Harbin Institute of Technology Harbin 15001 China Department of Physics & Materials Science City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong State Key Lab. of Welding Production Technology School of Mater. Sci. & Eng. Harbin Institute of Technology Harbin 15001 China Department of Physics & Materials Science City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong State Key Lab. of Welding Production Technology School of Mater. Sci. & Eng. Harbin Institute of Technology Harbin 15001 China Department of Physics & Materials Science City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong State Key Lab. of Welding Production Technology School of Mater. Sci. & Eng. Harbin Institute of Technology Harbin 15001 China Department of Physics & Materials Science City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong State Key Lab. of Welding Production Technology School of Mater. Sci. & Eng. Harbin Institute of Technology Harbin 15001 China Department of Physics & Materials Science City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong

Plasma ion implantation, an alternative to conventional beam-line ion implantation, is a sheath-acceleration ionbombardment technique and the initial sheath is crucial to the process efficacy and surface properties. The initialspatial potential distribution in the plasma sheath around a trench-shaped target is simulated using a two-dimensionalmodel in this work. The results demonstrate that the sheath structure depends very much on the trench width. Thepotential drop in the trench may be quite small and the sheath expands outward if the width is small. This leadsto a smaller incident ion dose into the sidewalls of the trench. In contrast, the initial potential distribution in thecentral region is quite similar to that without a trench if the trench width is larger than twice the ion-matrix sheaththickness for an infinite plane. Consequently, a higher ion dose into the sidewalls is possible.

关键词： Plasma ion implantation, Trench target, Potential distribution

Escherichia coli-host macrophage interactions in the pathogenesis of inflammatory bowel disease

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World Journal of Gastroenterology 2014年第27期20卷 8751-8763页

作者： Ahmed Tawfik paul k Flanagan Barry J Campbell Department of Gastroenterology Institute of Translational Medicine University of Liverpool

Multiple studies have demonstrated alterations in the intestinal microbial community (termed the microbiome) in Crohn’s disease (CD) and several lines of evidence suggest these changes may have a significant role in disease pathogenesis. In active and quiescent disease, both the faecal and mucosa-associated microbiome are discordant with matched controls with reduced biodiversity, changes in dominant organisms and increased temporal variation described. Mucosa-associated adherent, invasive Escherichia coli (E. coli) (AIEC), pro-inflammatory and resistant to killing by mucosal macrophages, appear to be particularly important. AIEC possess several virulence factors which may confer pathogenic potential in CD. Type-1 pili (FimH) allow adherence to intestinal cells via cell-surface carcinoembryonic antigen-related cell adhesion molecules and possession of long polar fimbrae promotes translocation across the intestinal mucosa via microfold (M)-cells of the follicle-associated epithelium. Resistance to stress genes (htrA, dsbA and hfq) and tolerance of an acidic pH may contribute to survival within the phagolysosomal environment. Here we review the current understanding of the role of mucosa-associated E. coli in Crohn’s pathogenesis, the role of the innate immune system, factors which may contribute to prolonged bacterial survival and therapeutic strategies to target intracellular E. coli.

关键词： Crohn's disease Inflammatory bowel disease Escherichia coli Intra-macrophage survival and replication Phagolysosome Autophagy

Assessing genetic diversity and structure of fragmented populations of eastern white pine(Pinus strobus)and western white pine(***)for conservation management

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Journal of Plant Ecology 2009年第3期2卷 143-151页

作者： Melanie Mehes kabwe k.Nkongolo paul Michael Department of Biology Laurentian UniversitySudburyOntarioCanada P3E 2C6

Aims Many pine populations in Canada have fragmented distributions resulting from the effects of glaciations,overharvesting and white pine blister rust *** fragmentation can modify gene flow and reduce genetic *** logging can reduce the density of trees,thereby altering mating patterns and increasing *** hypothesis of the present study is that forest fragmentation will not increase inbreeding and will have no effect on genetic diversity parameters in the Canadian Pinus moniticola and *** populations targeted because of(i)the long life span of the pine species,(ii)outbreeding and self-incompatibility of *** and *** and(iii)wind pollination resulting in high gene flow among *** studied the genetic diversity of *** across its range in Canada,and we completed a detailed analysis of the genetic structure of *** populations from western Canada using microsatellites genetic *** Seed samples from 10 *** populations and 10 *** populations were collected from western and eastern Canada,*** mother trees included in seed lots were representative of each *** DNA extracted from each sample was amplified with microsatellite *** intra-and interpopulation genetic diversity parameters were assessed using Popgene and Genepop softwares and the genetic distances among populations within each species using the PowerMarker software.

关键词： Pinus strobus Pinus monticola microsatellite genetic diversity forest fragmentation

Microwave Synthesis of Cuprous Oxide Micro-/Nanocrystals with Different Morphologies and Photocatalytic Activities

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Journal of Materials Science & Technology 2011年第4期27卷 289-295页

作者： Qingwei Zhu Yihe Zhang Jiajun Wang Fengshan Zhou paul k. Chu State key Laboratory of Geological Processes & Mineral Resources National Laboratory of Mineral Materials School of Materials Science and Technology China University of Geosciences (Beijing) Beijing 100083 China Department of Powder Metallurgy and Special Materials General Research Institute of Non-Ferrous MetalBeijing 100088 China Department of Physics & Materials Science City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong China

Cuprous oxide micro-/nanocrystals were synthesized by using a simple liquid phase reduction process under microwave irradiation. Copper sulfate was used as the starting materials and macromolecule surfactants served as the templates. The morphologies phase and optical properties of them are characterized by X-ray diffraction （XRD）, scanning elec- tron microscopy （SEM） and ultraviolet-visible diffuse reflection absorptive spectra （UV-vis/DRS）, respectively. The crystals had four different shapes, namely spheres, strips, octahedrons, and dandelions. The photocatalytic behavior of the cuprous oxide particles were investigated by monitoring the degradation of rhodamine B. In spite of the differ- ent morphologies, all of the cuprous oxide micro-/nanocrystals exhibited photocatalytic activities under visible light irradiation in the following order： dandelions, strips, spheres, and octahedral crystals. The photocatalytic degradation rates of rhodamine B are 56.37%, 55.68%, 51.83% and 46.16%, respectively. The morphology affects significantly the photocatalytic performance.

关键词： Cuprous oxide Synthesis Morphology Photocatalytsis

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中国心力衰竭流行病学调查及其患病率

中华心血管病杂志 2003年第1期31卷 3-6页

作者：顾东风黄广勇吴锡桂段秀芳何江 paul k.whelton Stephen Mac Mahon 中国医学科学院中国协和医科大学阜外心血管病医院群体遗传与防治研究室北京100037 美国Tulane大学健康科学中心澳大利亚悉尼大学医学院

目的　了解我国成年人慢性心力衰竭 (心衰 )的患病率和分布特征。方法　中国心血管健康多中心合作研究应用四阶段整群随机抽样方法 ,在全国 1 0个省市 (南方和北方各 5个省市 )抽取具有代表性的样本 ,年龄在 35～ 74岁之间 ,城市和农村... 详细信息

目的　了解我国成年人慢性心力衰竭 (心衰 )的患病率和分布特征。方法　中国心血管健康多中心合作研究应用四阶段整群随机抽样方法 ,在全国 1 0个省市 (南方和北方各 5个省市 )抽取具有代表性的样本 ,年龄在 35～ 74岁之间 ,城市和农村各半 ,男、女人数均衡。统计不同年龄组、不同性别和不同地区人群的心衰患病率。结果　共抽样调查 35～ 74岁城乡居民 1 5 51 8人 ,心衰患病率为0 9% ;其中男性为 0 7% ,女性为 1 0 % ,女性患病率高于男性 (P <0 0 5)。 35～ 44岁、45～ 54岁、55～64岁、65～ 74岁年龄组的心衰患病率分别为 0 4%、1 0 %、1 3 %和 1 3 % ;随着年龄增高 ,心衰的患病率显著上升 (P <0 0 1 )。我国北方地区心衰患病率为 1 4% ,南方地区心衰患病率为 0 5 % ,北方明显高于南方 (P <0 0 1 ) ;城市人群心衰患病率为 1 1 % ,农村人群心衰患病率为 0 8% ,城市人群心衰患病率高于农村。

关键词：成年人统计学心血管病中国心力衰竭流行病学调查患病率

Regulation of TiO_(2) nanoarrays on titanium implants for enhanced osteogenic activity and immunomodulation

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Journal of Materials Science & Technology 2023年第19期150卷 233-244页

作者： Ruoyu Li Hongyu Zhang Xiaohong Yao Bin Tang paul k Chu Xiangyu Zhang Shanxi key Laboratory of Biomedical Metal Materials College of Materials Science and EngineeringTaiyuan University of TechnologyTaiyuan 030024China Department of Occupational Disease Second Hospital of Shanxi Medical UniversityTaiyuan 030001China Department of Physics Department of Materials Science and Engineeringand Department of Biomedical EngineeringCity University of Hong KongTat Chee AvenueKowloonHong KongChina College of Biomedical Engineering Taiyuan University of TechnologyTaiyuan 030024China

The surface topography of implants plays a major role in osteogenesis and *** this study,three types of TiO_(2) nanoarrays including nanorod arrays with a diameter of 45 nm(TiO_(2)-N),nanorod arrays with a diameter of 60 nm(TiO_(2)-N N),and nanocone arrays(TiO_(2)-NW)are prepared on titanium and the behavior of bone marrow stromal cells(BMSCs)and polarization of macrophages are *** to the planar titanium control,TiO_(2) nanoarrays facilitate osteogenesis of BMSCs and stimulate the pro-healing M2 ***,adhesion,spreading,proliferation,and osteogenic differentiation of BMSCs are more pronounced on TiO_(2)-N N than both TiO_(2)-N and TiO_(2)-***_(2)-NN also produces the best immune microenvironment,while TiO_(2)-NW is more favorable than TiO_(2)-NN from the viewpoint of cell adhesion and spreading of osteoblasts.

关键词： TiO_(2)nanoarrays Osteogenic activity Immunomodulation Hydrothermal treatment

COVID-19 and gut immunomodulation

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World Journal of Gastroenterology 2021年第46期27卷 7925-7942页

作者： koushik Roy Sidra Agarwal Rajib Banerjee Manash k paul Prabhat k Purbey Microbiology and Immunology Department of PathologySchool of MedicineUniversity of UtahSalt Lake CityUT 84112United States Department of Gastroenterology Shadan Institute of Medical SciencesPeeramcheru 500086TelanganaIndia Department of Electronics and Communication Engineering Dr.B.C.Roy Engineering CollegeDurgapur 713206West BengalIndia Division of Pulmonary and Critical Care Medicine David Geffen School of MedicineUniversity of California Los AngelesLos AngelesCA 90095United States Department of Microbiology Immunology and Molecular GeneticsUniversity of California Los AngelesLos AngelesCA 90095United States

The disease coronavirus disease 2019(COVID-19)is a severe respiratory illness that has emerged as a devastating health problem *** disease outcome is heterogeneous,and severity is likely dependent on the immunity of infected individuals and *** symptoms of the disease are primarily associated with respiratory problems,additional infection or failure of other vital organs are being *** reports suggest a quite common co-existence of gastrointestinal(GI)tract symptoms in addition to respiratory symptoms in many COVID-19 patients,and some patients show just the GI *** possible cause of the GI symptoms could be due to direct infection of the epithelial cells of the gut,which is supported by the fact that(1)The intestinal epithelium expresses a high level of angiotensin-converting enzyme-2 and transmembrane protease serine 2 protein that are required for the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)entry into the cells;(2)About half of the severe COVID-19 patients show viral RNA in their feces and various parts of the GI tract;and(3)SARS-CoV-2 can directly infect gut epithelial cells in vitro(gut epithelial cells and organoids)and in vivo(rhesus monkey).The GI tract seems to be a site of active innate and adaptive immune responses to SARS-CoV-2 as clinically,stool samples of COVID-19 patients possess proinflammatory cytokines(interleukin 8),calprotectin(neutrophils activity),and immunoglobulin A *** addition to direct immune activation by the virus,impairment of GI epithelium integrity can evoke immune response under the influence of systemic cytokines,hypoxia,and changes in gut microbiota(dysbiosis)due to infection of the respiratory system,which is confirmed by the observation that not all of the GI symptomatic patients are viral RNA *** review comprehensively summarizes the possible GI immunomodulation by SARS-CoV-2 that could lead to GI symptoms,their association with disease sev

关键词： COVID-19 Gastrointestinal symptoms Pathogenesis Innate immune response Adaptive immune response Gut microbiota Dysbiosis Therapeutics Probiotic Pre-existing diseases

Uniformity of Plasma Density and Film Thickness of Coatings Deposited Inside a Cylindrical Tribe by Radio Frequency Sputtering

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Plasma Science and Technology 2008年第5期10卷 560-564页

作者：崔江涛田修波杨士勤胡涛 Ricky k.Y.FU paul k.CHU School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Department of Physics and Material Science City University of Hong KongTat Chee AvenueKowloonHong KongChina

Plasma surface modification of the inner wall of a slender tube is quite difficult to achieve using conventional means. In the work described here, an inner coaxial radio frequency （RF） copper electrode is utilized to produce the plasma and also acts as the sputtered target to deposit copper films in a tube. The influence of RF power, gas pressure, and bias voltage on the distribution of plasma density and the uniformity of film thickness is investigated. The experimental results show that the plasma density is higher at the two ends and lower in the middle of the tube. A higher RF power and pressure as well as larger tube bias lead to a higher plasma density. Changes in the discharge parameter only affect the plasma density uniformity slightly. The variation in the film thickness is consistent with that of the plasma density along the tube axis for different RF power and pressure. Although the plasma density increases with higher tube biases, there is an optimal bias to obtain the highest deposition rate. It can be attributed to the reduction in self-sputtering of the copper electrode and re-sputtering effects of the deposited film at higher tube biases.

关键词： plasma distribution inner surface radio-frequency plasma