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A COMPACT f-SPACE NOT CO-ABSOLUTE WITH BETA-N-N

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TOPOLOGY AND ITS APPLICATIONS 1983年第1期15卷 59-64页

作者： VANMILL, J WILLIAMS, SW SUNY BUFFALO BUFFALONY 14214

We show that if every Parovičenko space of weight c is co-absolute with β N − N , then c <2 ℵ 1 .

关键词： 54G05, 54D40, 54A35, 06E99 f -space absolute β N − N Boolean alegbra Continuum Hypothesis

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PROTEINS CONTAINING THE fACTOR-f430 fROM METHANOSARCINA-BARKERI AND METHANOBACTERIUM-THERMOAUTOTROPHICUM - ISOLATION AND PROPERTIES

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BIOCHIMICA ET BIOPHYSICA ACTA 1983年第1期742卷 84-90页

作者： MOURA, I MOURA, JJG SANTOS, H XAVIER, AV BURCH, G PECK, HD LEGALL, J INST SUPER TECN CTR QUIM ESTRUTURAL COMPLEXO I AVE ROVISCO PAIS P-1000 Lisbon PORTUGAL UNIV MINNESOTA GRAY FRESHWATER BIOL INST NAVARRE MN 55392 USA UNIV GEORGIA DEPT BIOCHEM ATHENS GA 30602 USA

for the 1st time, the unique Ni-containing cofactor (compound f430) has been shown to exist in a protein-bound form. The proteins isolated from Methanosarcina barkeri and Methanobacterium thermoautotrophicum were designated P425''(445'') on the basis of their spectral characteristics. The proteins contained 3 different subunits and had MW of .apprx. 300,000. Heat treatment or acidification of the proteins releases an f430 cofactor identical to the one isolated in Methanobacterium bryantii and Methanobacterium thermoautotrophicum.

关键词： Methanogenic bacterium f 430 Nickel protein

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SARC-f for screening of sarcopenia among older adults with cancer

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CANCER 2021年第9期127卷 1469-1475页

作者： Williams, Grant R. Al-Obaidi, Mustafa Dai, Chen Bhatia, Smita Giri, Smith Univ Alabama Birmingham Inst Canc Outcomes & Survivorship Birmingham AL 35233 USA Univ Alabama Birmingham Dept Med Div Hematol & Oncol Birmingham AL 35233 USA

Background Sarcopenia is associated with adverse outcomes among older adults with cancer;however, no easily applied sarcopenia measure exists for use in clinical practice. The use of SARC-f, a 5-item self-reported sarcopenia screening questionnaire, among older adults with cancer remains to be investigated. Methods Older adults (aged >= 60 years) with cancer enrolled in the University of Alabama Cancer and Aging Resilience Evaluation Registry were identified. Patients completed the SARC-f questionnaire (with scores >= 4 considered positive for sarcopenia). The authors assessed for differences in geriatric assessment domain impairments, health-related quality of life, and health care utilization between those with and without sarcopenia using multivariate regression, then assessed the association of sarcopenia with survival using Kaplan-Meier methods and a Cox regression model, adjusting for covariates. Results In total, 256 older adults were identified. The median age was 69 years, 59% of participants were men, and 75% were White. The median SARC-f score was 2 (interquartile range, 0-4), and 33% of participants screened positive. Those with sarcopenia had higher odds of having multiple impairments, including impaired instrumental activities of daily living (adjusted odds ratio [aOR], 18.1;95% CI, 7.5-43.8) and frailty (aOR, 43.5;95% CI, 17.7-106.8) as well as reduced physical and mental health-related quality of life (beta coefficient, -13.6 and -11.5, respectively) and increased emergency room visits (aOR, 2.4;95% CI, 1.3-4.7). furthermore, sarcopenia was independently associated with inferior overall survival (adjusted hazard ratio, 2.98;95% CI, 1.1-8.3;P = .04). Conclusions One-third of older adults with cancer in this cohort screened positive for sarcopenia using the SARC-f screening questionnaire, and these positive scores are associated with geriatric assessment domain impairments, reduced health-related quality of life, increased emergency room visits, and in

关键词： aging cancer geriatric assessment geriatric oncology SARC‐ f sarcopenia

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Bioactive compounds from the fruit extract of Clausena excavata Burm. f. (Rutaceae)

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SOUTH AfRICAN JOURNAL Of BOTANY 2022年第PartB期151卷 538-548页

作者： Suthiphasilp, Virayu Maneerat, Tharakorn Laphookhieo, Surat Songkerdthong, Jetnipat Harding, David J. Charoensup, Rawiwan Mae Fah Luang Univ Ctr Chem Innovat Sustainabil CIS Sch Sci Chiang Rai 57100 Thailand Mae Fah Luang Univ Med Plant Innovat Ctr Chiang Rai 57100 Thailand Walailak Univ Funct Mat & Nanotechnol Ctr Excellence FuNTech ThasalaNakhon Si Thammar 80160 Thailand Mae Fah Luang Univ Sch Integrat Med Chiang Rai 57100 Thailand

Phytochemical investigation of the fruit extract of Clausena excavata Burm. f. resulted in the isolation and identification of 16 compounds, including seven coumarins (1-7), four phenylpropanoids (8-10 and 14), two benzaldehyde derivatives (11 and 12), one carbazole alkaloid (13), and two limonoids (15 and 16). Of these, nine compounds (1, 3, 5, 6, 8-10, 15, and 16) were isolated from C. excavata for the first time. The absolute configuration of limonoids 15 and 16 was established by X-ray diffraction analysis using Cu Ka radiation. Some isolated compounds were evaluated for their in vitro cytotoxicity against three human cancer cell lines, namely lung cancer A549, colorectal cancer SW480, leukemic K562 cells as well as glucose uptake, glucose consumption, and antibacterial activity against Staphylococcus aureus (SA) and methicillin-resistant Staphylococcus aureus (MRSA). Compounds 7 (auraptene) and 14 (safrole) showed moderate glucose uptake with ratios of 1.38-fold and 1.41-fold compared to the positive control (metformin, 2.25-fold). Compound 7 (auraptene) also exhibited weak cytotoxicity against lung cancer A549, colorectal cancer SW480, and leukemic K562 cells with IC50 values of 77.2, 157.3, and 105.3 mu M, respectively, while compounds 8 ((E)-piperonylprop-2-enal) and 10 (ethyl p-coumarate) exhibited weak cytotoxicity against RAW 264.7 cells and colorectal cancer SW480 cells with IC50 values of 234.9 and 219.5 mu M, respectively. Compounds 1, 3, 7, and 14-16 showed a MIC of >512 mu g/mL revealing them to be inactive.(c) 2022 SAAB. Published by Elsevier B.V. All rights reserved.

关键词： Clausena excavata Burm f Rutaceae Antidiabetic Anticancer Antibacterial

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MECHANISM Of THE LIGHT STATE TRANSITION IN PHOTOSYNTHESIS .1. ANALYSIS Of THE KINETICS Of CYTOCHROME-f OXIDATION IN STATE-1 AND STATE-2 IN THE RED ALGA, PORPHYRIDIUM-CRUENTUM

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BIOCHIMICA ET BIOPHYSICA ACTA 1983年第1期724卷 111-117页

作者： BIGGINS, J BROWN UNIV DIV BIOL & MED PROVIDENCE RI 02912 USA

The kinetics of photooxidation and reduction of cytochrome [cyt] f were examined spectrophotometrically in the red alga P. cruentum in light state 1 and light state 2. Experiments were performed on intact cells that had been chemically fixed and stabilized in the light states. The cyt f turnover was measured during conditions of linear electron transport driven by both photosystems and during several cyclic reactions mediated by the long-wavelength photosystem (PS) I. The rate of photooxidation of cyt f increased in state 2 when the cells were activated by subsaturating intensities of green light absorbed primarily by the phycobilisome. No differences in kinetics were found between algae in state 1 or state 2 when they were activated by light absorbed primarily by the chlorophyll of PS I. Changes in energy distribution between the 2 photosystems occur as a result of the light state transition and verify that the redistribution of excitation results in the predicted changes in electron transport.

关键词： Cytochrome f oxidation Photosynthesis Light state transition Electron transport fluorescence (Porphyridium cruentum) PS photosystem LHC light-harvesting chlorophyll a b protein DCMU 2-(3,4-dichlorophenyl)-1,1-dimethylurea TMPD N , N , N ′, N ′-tetramethyl- p -phenylenediamine DCIP 2,6-dichlorophenolindophenol

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Two new isoquinoline alkaloids from Hypecoum leptocarpum Hook. f. et Thoms

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NATURAL PRODUCT RESEARCH 2024年第8期38卷 1392-1397页

作者： Wen, Huaixiu Yuan, Xiang Li, Caixia Li, Jun Yue, Huilan Chinese Acad Sci Northwest Inst Plateau Biol Qinghai Prov Key Lab Tibetan Med Res Xining Peoples R China Chinese Acad Sci Northwest Inst Plateau Biol Key Lab Tibetan Med Res Xining Peoples R China Chinese Acad Med Sci & Peking Union Med Coll Inst Mat Med Beijing Peoples R China Ningxia Vocat & Tech Coll Dept Biol & Pharmaceut Technol Yinchuan Ningxia Peoples R China

Two new isoquinoline alkaloids, hypecocarpinine (1) and leptocaramine (2) along with five known ones including leptopidine (3), corydamine (4), protopine (5), dihydroprotopine (6) and oxohydrastinine (7), were isolated from Hypecoum leptocarpum Hook. f. et Thoms. Structures of the compounds were elucidated using spectroscopic methods, including UV, IR, HR-ESI-MS, 1 D and 2 D NMR. The cytotoxic activities of these compounds were evaluated using MTT assay. The results showed that compounds 2, 4, and 7 have moderate cytotoxicity against human lung cancer (A549) and human gastric carcinoma (MGC-803) cell lines.

关键词： Isoquinoline alkaloid Hypecoum leptocarpum Hook f et Thoms cytotoxic activities

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STUDIES ON THE CYTOCHROME B6/f COMPLEX .1. CHARACTERIZATION Of THE COMPLEX SUBUNITS IN CHLAMYDOMONAS-REINHARDTII

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BIOCHIMICA ET BIOPHYSICA ACTA 1986年第2期851卷 229-238页

作者： LEMAIRE, C GIRARDBASCOU, J WOLLMAN, fA BENNOUN, P INST BIOLOGIE PHYS CHIM SERV PHOTOSYNTHESE 13 RUE PIERRE & MARIE CURIE F-75231 PARIS 05 FRANCE

We have analyzed the heme-associated peroxidase activity in thylakoid membranes from the green algae Chlamydomonas reinhardtii after electrophoresis in the presence of sodium dodecyl sulfate. Besides cytochrome f and cytochrome b6, we observed peroxidase activity in two other bands, of 34 and 11 kDa, of unknown origin. Characterization of the b6/f complex subunits was undertaken by means of a comparison of the polypeptide deficiencies in several b6/f mutants with the polypeptide content of preparations enriched in b6/f complexes. We conclude that the b6/f complex consists of five subunits. Using site-specific translation inhibitors, we show that cytochrome f, cytochrome b6 and subunit IV are of chloroplast origin, whereas the Rieske protein and probably subunit V are translated on cytoplasmic ribosomes. A model of assembly of the complex is proposed: a cytochrome moiety, comprising the subunits of chloroplast origin, is assembled in the thylakoid membranes prior to the insertion and assembly of the subunits encoded in the nuclear genome.

关键词： Cytochrome b 6 / f complex Peroxidase Thylakoid membrane Protein assembly Chloroplast biogenesis Cyt cytochrome PS Photosystem HP high potential LP low potential α antibody TMBZ 3,3′,5,5′-tetramethylbenzidine DCMU 3-(3,4-dichlorophenyl)-1,1-dimethylurea PBS phosphate-buffered saline f 0 initial yield of fluorescence f max maximal yield of fluorescence

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Degassing of Cl, f, Li, and Be during extrusion and crystallization of the rhyolite dome at Volcan Chaiten, Chile during 2008 and 2009

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BULLETIN Of VOLCANOLOGY 2012年第10期74卷 2303-2319页

作者： Lowenstern, Jacob B. Bleick, Heather Vazquez, Jorge A. Castro, Jonathan M. Larson, Peter B. US Geol Survey Menlo Pk CA 94025 USA Johannes Gutenberg Univ Mainz Mainz Germany Washington State Univ Pullman WA 99164 USA

We investigated the distribution of Cl, f, Li, and Be in pumices, obsidians, and crystallized dome rocks at Chait,n volcano in 2008-2009 in order to explore the behavior of these elements during explosive and effusive volcanic activity. Electron and ion microprobe analyses of matrix and inclusion glasses from pumice, obsidian, and microlite-rich dome rock indicate that Cl and other elements were lost primarily during crystallization of the rhyolitic dome after it had approached the surface. Glass in pumice and microlite-free obsidian has 888 +/- 121 ppm Cl, whereas residual glass in evolved microlite-rich dome rock generally retains less Cl (as low as < 100 ppm). Estimated Cl losses were likely > 0.7 Mt Cl, with a potential maximum of 1.8 Mt for the entire 0.8-km(3) dome. Elemental variations reflect an integrated bulk distribution ratio for Cl > 1.7 (1.7 times more Cl was degassed or incorporated into crystals than remained in the melt). Because Cl is lost dominantly as the very last H2O is degassed, and Cl is minimally (if at all) partitioned into microlites, the integrated vapor/melt distribution ratio for Cl exceeds 200 (200 times more Cl in the evolved vapor than in the melt). Cl is likely lost as HCl, which is readily partitioned into magmatic vapor at low pressure. Cl loss is accelerated by the change in the composition of the residual melt due to microlite growth. Cl loss also may be affected by open-system gas fluxing. Integrated vapor-melt distribution ratios for Li, f, and Be all exceed 1,000. On degassing, an unknown fraction of these volatiles could be immediately dissolved in rainwater.

关键词： Chlorine Halogens fluorine Lithium Beryllium Be f Li Cl Rhyolite Volatility Degassing

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TOPOGRAPHICAL STUDIES Of THE POLYPEPTIDE SUBUNITS Of THE THYLAKOID CYTOCHROME-B6-f COMPLEX

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BIOCHIMICA ET BIOPHYSICA ACTA 1985年第1期808卷 164-170页

作者： ORTIZ, W MALKIN, R UNIV CALIF BERKELEY DIV MOLEC PLANT BIOL 313 HILGARD HALL BERKELEY CA 94720 USA

The orientation of specific polypeptides of the cytochrome b6-f complex with respect to the chloroplast stromal phase was studied using trinitrobenzenesulfonate (TNBS) and pronase E as impermeant modifying reagents. Of the 4 polypeptides of the complex (33, 23, 20 and 17 kilodaltons) only cytochrome f was labeled by 14C-TNBS in unfractionated membranes. However, to a varying degree, all of the constitutent polypeptides were sensitive to pronase digestion and, in the case of cytochrome f, it was possible by immunoblotting techniques to idenify several degradation products. These results are discussed in relation to the organization of the cytochrome complex in thylakoid membranes and argue for an exposure to the stromal phase of all of the polypeptides, while functional considerations indicate that at least cytochrome f and the Rieske fe-S protein have a possible transmembrane organization.

关键词： Thylakoid membrane Cytochrome b 6 - f complex Chemical modification Cytochrome f Rieske iron-sulfur protein (Spinach chloroplast) TNBS trinitrobenzenesulfonate Chl chlorophyll Cyt c cytochrome c LHCP light-harvesting chlorophyll-protein complex

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MONOCLONAL IMMUNOASSAYS fOR MAJOR DUST MITE (DERMATOPHAGOIDES) ALLERGENS, DER-P-I AND DER-f-I, AND QUANTITATIVE-ANALYSIS Of THE ALLERGEN CONTENT Of MITE AND HOUSE DUST EXTRACTS

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JOURNAL Of ALLERGY AND CLINICAL IMMUNOLOGY 1987年第2期80卷 184-194页

作者： CHAPMAN, MD HEYMANN, PW WILKINS, SR BROWN, MJ PLATTSMILLS, TAE UNIV VIRGINIA MED CTR DEPT MED DIV ALLERGY & CLIN IMMUNOL BOX 225 CHARLOTTESVILLE VA 22908 USA

Monoclonal, two-site radioimmunoassay (RIAs) were developed to measure allergen Der p I of Dermatophagoides pteronyssinus or Der f I of D. farinae. Microtiter plates coated with monoclonal antibody (Mab) were incubated with mite extract, and bound allergen was detected with a second 125I-labeled Mab of different epitope specificity. The Mab RIAs were very sensitive (nanogram range) and highly specific. D. pteronyssinus extracts with different concentrations of Der p I demonstrated parallel binding curves, whereas a potent D. farinae extract demonstrated < 5% of the Der p I binding in the same assay. Similar parallel curves were obtained with several D. farinae extracts in the Der f I assay, whereas D. pteronyssinus extract demonstrated little or no binding. The Mab RIAs were compared with an inhibition RIA that measured cross-reacting determinants on both Der p I and Der f I (antigen P1 equivalent [AgP1Eq]). The results demonstrated good quantitative agreement between these assays in commercial mite and house dust extracts (mean difference 1.57 .+-. 0.5-fold). Thirty house dust samples with known mite counts. Der p I, and AgP1Eq content were also compared. The summed Mab RIA values for Der p I and Der f I demonstrated a very good correlations with AgP1Eq values (r = 0.86;p < 0.001) and with assessments of total mite-allergen content by RAST inhibition (n = 21, r = 0.77, p < 0.001). furthermore, in samples with more than 10 mites per 100 mg of dust, the Der p I: Der f I ratio closely correlated with the ratio of the two mites counted by microscopy (n = 15, r = 0.89;p < 0.001). The Mab RIAs can measure allergen levels in mite or dust extracts without the need for purified allergen or affinity-purified antibodies and can readily be standardized. These assays will be useful in epidemiologic studies of allergic asthma, to assess patients'' exposure to mite allergens, and the effects of avoidance regimens. Because of the long-term stability and reproducibility of the reag

关键词： Mab Monoclonal antibody RIA Radioimmunoassay Der p I A major 24,000 MW allergen of Dermatophagoides pteronyssinus Der f I A major 24,000 MW allergen of D. farinae WHO/IUIS World Health Organization/Intemational Union of Immunological Societies NIBSC National Institute for Biological Standards and Control UVA University of Virginia SAS Saturated ammonium sulfate PBS-T Phosphate-buffered saline, pH 7.2 containing 0.05% Tween 20 BBS Borate-buffered saline, pH 8.0 BSA Bovine serum albumin AgP 1 Eq Antigen P 1 equivalent 10B9 Anti- Der p I monoclonal antibody 10B9 f6 A12 5H8 Anti- Der p I monoclonal antibody 5H8 C12 D9 6A8 Anti- Der f I monoclonal antibody 6A8 BIO D12 4C1 Monoclonal antibody 4Cl B8 3f8 that recognizes both Der p I and Der f I

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