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Antiviral polysaccharides isolated from Hong Kong brown seaweed Hydroclathrus clathratus

作者： (英)j.m. 巴里(j.m. Barrie)

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Science China(Life Sciences) 2007年第5期50卷 611-618页

作者： OOI Engchoon Vincent ANG Put O jr. Department of Biology the Chinese University of Hong Kong Shatin N.T. Hong Kong SAR China

Two relatively pure polysaccharides H3-a1 and H3-b1 had been isolated from the brown seaweed Hy-droclathrus clathratus. They were characterized by HPLC, ultraviolet scanning, gas chromatography, infrared spectroscopy and elemental analysis, and shown to be two different sulfated polysaccharides with different monosaccharide content, but both with high relative molecular mass. They contained some proteins and uronic acid respectively. The sulfate content and bioactivity of these polysaccha-rides varied during purification. The fractions derived from the hot water extract also exhibited low anticoagulant effect. This is the first time that the antiherpetic and anticoagulant activities were evaluated for the polysaccharides from the Hong Kong brown seaweed Hydroclathrus clathratus.

关键词： Hong Kong seaweed, Hydroclathrus clathratus, antiviral polysaccharide, polysaccharide characterization

Stability analysis of the sliding process of the west slope in Buzhaoba Open-Pit mine

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International journal of mining Science and Technology 2016年第5期26卷 869-875页

作者： Ning Fang ji Changsheng Garmondyu E.Crusoe jr. School of Art and Design School of Mines China University of Mining & Technology

To study the stability of the west slope in Buzhaoba Open-Pit mine and determine the aging stability coefficient during slide mass development, the deformation band of the west slope and the slide mass structure of the 34,600 profile are obtained on the basis of hydrology, geology, and monitoring *** residual thrust method is utilized to calculate the stability coefficients, which are 1.225 and 1.00 under sound and transfixion conditions, respectively. According to the rock damage and fragmentation and the principle of mechanical parameter degradation, the mechanical models of the slide mass development of the hard and soft rock slopes are established. An integrated model for calculating the slope stability coefficient is built considering water, vibration, and other external factors that pertain to the structural plane damage mechanism and the generating mechanism of the sliding mass. The change curve of the stability coefficient in the slide mass development is obtained from the relevant analyses,and afterwards, the stability control measures are proposed. The analysis results indicate that in the cracking stage of the hard rock, the slope stability coefficient decreases linearly with the increase in the length Lbof the hard rock crack zone. The linear slope is positively correlated to rock cohesion c. In the transfixion stage of the soft rock, the decrease speed of the stability coefficient is positively correlated to the residual strength of the soft rock. When the slope is stable, the stability coefficient is in a quadratic-linear relationship with the decreased height Dh of the side slope and in a linear relationship with anchoring force P.

关键词： Open-pit mine Side slope Sliding process Aging stability Crack zone

Design of Agents Interacting with Immunoregulating Proteins:Potential Inhibitors of the Phenylpyruvate Tautomerase Activity Catalysed by macrophage migration Inhibitory Factor (mIF)

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Chinese journal of Chemistry 2003年第10期21卷 1256-1262页

作者： CARPY Alain j.m. HAASBROEK P.P. OLIVER D.W. PTC-UmR 5472 CNRS Department of Pharmacy and PharmacologyPharmacology Faculty of Health Science University of Bordeaux ITalence France University of Witwatersrand JohannesburgSouth AfricaPotchefstroom University for CHE PotchefstroomSouth Africa

The macrophage migration inhibitory factor has been implicated in a number ofimmune and inflammatory processes. mIF presents particular opportunities for drug design anddevelopment with potential therapeutic applications. Drug design strategies taking intoconsideration of specific stereochemical and tautomeric requirements in the interaction of mIF withsubstrates and inhibitors allow several novel structures to be designed. Our investigationssuccessfully explored the tautomeric and stereochemical aspects of new compounds of the2-phenylpyruvic acid type, both experimentally, through synthesis and structural investigations andcomputationally, through molecular mechanics and quantum mechanics calculations.

关键词： macrophage migration inhibitory factor phenylpyru-vate tautomerase activity azlactone phenylpyruvic acid derivative

Putting it all together： intrinsic and extrinsic mechanisms governing proteasome biogenesis

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Frontiers in Biology 2017年第1期12卷 19-48页

作者： Lauren A. Howell Robert j. Tomko jr. Andrew R. Kusmierczyk Department of Biomedical Sciences Florida State University College of Medicine Tallahassee FL 32306 USA Department of Biology Indiana University-Purdue Universi~ Indianapolis Indianapolis IN 46202 USA

BACKGROUND： The 26S proteasome is at the heart of the ubiquitin-proteasome system, which is the key cellular pathway for the regulated degradation of proteins and enforcement of protein quality control. The 26S proteasome is an unusually large and complicated protease comprising a 28-subunit core particle （CP） capped by one or two 19-subunit regulatory particles （RP）. multiple activities within the RP process incoming ubiquitinated substrates for eventual degradation by the barrel-shaped CE The large size and elaborate architecture of the proteasome have made it an exceptional model for understanding mechanistic themes in macromolecular assembly. OBjECTIVE： In the present work, we highlight the most recent mechanistic insights into proteasome assembly, with particular emphasis on intrinsic and extrinsic factors regulating proteasome biogenesis. We also describe new and exciting questions arising about how proteasome assembly is regulated and deregulated in normal and diseased cells. mETHODS： A comprehensive literature search using the Pubmed search engine was performed, and key findings yielding mechanistic insight into proteasome assembly were included in this review. RESULTS： Key recent studies have revealed that proteasome biogenesis is dependent upon intrinsic features of the subunits themselves as well as extrinsic factors, many of which function as dedicated chaperones. CONCLUSION： Cells rely on a diverse set of mechanistic strategies to ensure the rapid, efficient, and faithful assembly of proteasomes from their cognate subunits. Importantly, physiological as well as pathological changes to proteasome assembly are emerging as exciting paradigms to alter protein degradation in vivo.

关键词： proteasome assembly assembly chaperones ubiquitin-proteasome system proteolysis macromolecular complex

Lophozonia tree cavities used for nesting by Slender-billed Parakeets(Enicognathus leptorhynchus)in the central valley of southern Chile:a potentially vanishing keystone resource

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Chinese Birds 2017年第1期8卷 25-36页

作者： Thomas H.White jr. jaime E.j.m.nez Puerto Rican Parrot Recovery Program United States Fish and Wildlife ServiceBox 1600Rio GrandePR 00745USA Sub-Antarctic Biocultural Conservation Program Department of Biological SciencesUniversity of North TexasDentonTX 76201USA Sub-Antarctic Biocultural Conservation Program Department of Philosophy and ReligionUniversity of North TexasDentonTX 76201USA Omora Etnobotanical Park Universidad de MagallanesPuerto WilliamsChile

Background: The Slender-billed Parakeet(Enicognathus leptorhynchus) is a psittacine endemic to southern Chile and an obligate secondary cavity-nester. In the central valley of southern Chile, most(94%) of the known Slender-billed Parakeet nests have occurred in large, mature southern beech(Lophozonia obliqua) trees(locally known as "pellines"). As relicts of the original old-growth forests of southern Chile, most pellines have been lost due to extensive landclearing throughout the region, potentially threatening long-term persistence of the Slender-billed ***: We conducted our study in the central valley of southern Chile, near the city of Osorno during three consecutive nesting seasons(November–january, 2008–2011). Nest trees used by Slender-billed Parakeets were located by direct observation of parakeet activities and through interviews with local residents, some of whom were former parrot nest poachers. Nest cavities were accessed, inspected and measured using single-rope climbing techniques. We report means, standard errors, 95% confidence intervals and ranges for 11 cavity-related variables. We also report clutch sizes encountered in active nests, and age estimates of nest trees based on known growth rates of Lophozonia trees in southern Chile. Linear regressions were used to evaluate potential relationships between cavity-related variables and clutch ***: We located and measured 38 Lophozonia tree cavities used for nesting by Slender-billed Parakeets. Compared to those used by other psittacines, nest trees were relatively large, averaging 30.4 breast height of 134.5 ter ± 1.1 m in height with a mean diameter at ± 4.7 cm. Based on estimated annual diameincrement, ages of nest trees ranged from approximately 209–485 years. Nest cavities entrances averaged 12.5 ± 0.9 m in height above ground level. Cavity entrance widths averaged 51.0 ± 13.3 cm(vertical) by 11.5 ± 0.7 cm(horizontal). Cavity entrance orientations were apparently random, with

关键词： Conservation Deforestation Habitat loss Lophozonia obliqua Pellines Psittacidae Regeneration

Photoluminescent Tb^(3+)-based metal-organic framework as a sensor for detection of methanol in ethanol fuel

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journal of Rare Earths 2019年第3期37卷 225-231页

作者： Ramon R.F.Fonseca Rafael D.L.Gaspar Ivo m.Raimundo jr. Priscilla P.Luz Department of Chemistry Federal University of Espírito Santo Institute of Chemistry University of Campinas

The sensing capability of a Tb^(3+)-metal-organic framework, based on its photoluminescence, was used for detection of methanol in ethanol fuel. It was synthesized using terbium and trimesic acid as a metal ion center and ligand, respectively. Powder X-ray diffraction, infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy were employed to characterize the synthesized mOF-76 structural features. According to the results, mOF-76 was successfully obtained with minor synthetic modification and its activated form(named TbTmA) was tested as a sensor for methanol. Tb^(3+) luminescence intensity increases as the methanol concentration in ethanol fuel also increases and the water content does not affect this response. Our findings indicate TbTmA as an appropriate sensor for evaluating ethanol fuel adulteration by methanol addition above the allowed limit.

关键词： Lanthanide metal-organic frameworks Luminescence Ethanol fuel Sensor Adulteration

HIV/HCV Antiviral Drug Interactions in the Era of Direct-acting Antivirals

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journal of Clinical and Translational Hepatology 2016年第3期4卷 234-240页

作者： Donald P.Rice jr. john j.Faragon Sarah Banks Lisa m.Chirch Division of Infectious Diseases Department of Medicine University of Connecticut School of Medicine Farmington CT USA Division of HIV medicine Albany Medical Center Albany NY USA Department of medicine The Hospital of Central ConnecticutUniversity of Connecticut School of Medicine Farmington CT USA

Therapy for human immunodeficiency virus (HIV) and chronic hepatitis C has evolved over the past decade,resulting in better control of infection and clinical outcomes;however,drug-drug interactions remain a significant *** recommendations from the American Association for the Study of Liver Diseases and the Infectious Diseases Society of America regarding drug-drug interactions between HIV antiretroviral agents and direct-acting antiviral agents for treatment of hepatitis C virus (HCV) infection are reviewed *** review is oriented to facilitate appropriate selection of an antiviral therapy regimen for HCV infection based on the choice of antiretroviral therapy being administered and,if necessary,switching antiretroviral regimens.

关键词： HIV Hepatitis C Direct-acting antivirals Drug interactions Pharmacokinetics Antiretroviral therapy

No signature of selection on the C-terminal region of glucose transporter 2 with the evolution of avian nectarivory

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Avian Research 2020年第4期11卷 380-390页

作者： Alexander m.myrka Tooba Shah jason T.Weir Kenneth C.Welch jr. Department of Cell and Systems Biology University of Toronto25 Harbord St.TorontoON M5S 3G5Canada Department of Biological Sciences University of Toronto Scarborough1265 Military TrailTorontoON M1C 1A4Canada Department of Ecology and Evolutionary Biology University of Toronto Scarborough1265 Military TrailTorontoON M1C 1A4Canada

Background:Flying birds,especially those that hover,need to meet high energetic *** that meet this demand through nectarivory face the added challenges of maintaining homeostasis in the face of spikes in blood sugar associated with nectar meals,as well as transporting that sugar to energetically demanding *** has evolved many times in birds and we hypothesized that the challenges of this dietary strategy would exert selective pressure on key aspects of metabolic ***,we hypothesized we would find convergent or parallel amino acid substitutions among different nectarivorous lineages in a protein important to sensing,regulating,and transporting glucose,glucose transporter 2(GLUT2).methods:Genetic sequences for GLUT2 were obtained from ten pairs of nectarivorous and non-nectarivorous sister *** performed PCR amplification of the intracellular C-terminal domain of GLUT2 and adjacent protein domains due to the role of this region in determination of transport rate,substrate specificity and ***:Our findings have ruled out the C-terminal regulatory region of GLUT2 as a target for selection by sugar-rich diet among avian nectarivores,though selection among hummingbirds,the oldest avian nectarivores,cannot be ***:Our results indicate future studies should examine down-stream targets of GLUT2-mediated glucosensing and insulin secretion,such as insulin receptors and their targets,as potential sites of selection by nectarivory in birds.

关键词： GLUT2 Nectarivory Avian Glucosensing Glucose Diet Insulin signalling

Reproductive potential of field-collected overwintering boll weevils （Coleoptera： Curculionidae） fed on pollen in the laboratory

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Insect Science 2009年第4期16卷 321-327页

作者： S. m. Greenberg G. D. jones j. j. Adamczyk, jr. F. Eischen j. S. Armstrong R. j. Coleman m. Setamou Tong-Xian Liu USDA-ARS-KSARC-BIRU 2413 E. Hwy. 83 Weslaco Texas 78596 APmRU-SPA-ARS-USDA College Station Texas 77845 USDA- ARS-KSA RC-Honey Bee Research Unit Texas A&m University Kingsville Citrus Center Weslaco TX 78596 Department of Entomology Texas AgriLife Research Texas A&M University System Weslaco Texas 78596 USA

The reproductive potential of overwintering boll weevil, Anthonomus grandis grandis （Boheman）, females collected from pheromone traps in September, November and january, fed for 1, 3, and 5 weeks on plant pollens, and then provided cotton squares, was determined in the laboratory at 27 ~ I^C, 65% RH, and a photoperiod 13 ： 11 （L ： D） h. Duration of pollen feeding by overwintering boll weevils did not significantly influence egg and feeding punctures, or puncture ratios （egg to total punctures） for any of the three months of parent weevil collections when provided cotton squares on a daily basis. However, punctures and puncture ratios are significantly different when comparing mean data between months of boll weevil collections. When boll weevils were provided with cotton squares daily, the pre-ovipositional periods of female parents captured in September, November and january were 5, 9 and 14 days, respectively. The rate of eggs by females was significantly lower during November and january than September. Female parents collected in September produced a significantly higher percentage of eggs yielding adult progeny than those collected in November and january. Life table parameters indicated that net reproductive rate （Ro） of boll weevil females collected in September was 1.2- fold higher than those collected in November and 10.7-fold higher than those collected in january. Except for testes size, no differences in male reproductive parameters were observed during the cotton-free period compared with males captured during mid-cotton （june）. The number of oocytes in the ovarioles and the number of ooeytes containing yolk were significantly lower during September, November and january compared with june. The reproductive potential ofoverwintering boll weevil females collected in different months is an important consideration in determining the success of any control strategy.

关键词： Anthonomusgrandisgrandis overwintering boll weevil reproductive pollen