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ANALYSIS Of CHLOROPHYLL fLUORESCENCE INDUCTION CURVES IN THE PRESENCE Of 3-(3,4-DICHLOROPHENYL)-1,1-DIMETHYLUREA AS A fUNCTION Of MAGNESIUM CONCENTRATION AND NADPH-ACTIVATED LIGHT-HARVESTING CHLOROPHYLL A/B-PROTEIN PHOSPHORYLATION

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BIOCHIMICA ET BIOPHYSICA ACTA 1983年第2期724卷 167-175页

作者： TELfER, A HODGES, M BARBER, J IMPERIAL COLL SCI & TECHNOL DEPT PURE & APPL BIOL ARC PHOTOSYNTH RES GRP LONDON SW7 2BB ENGLAND

The effect of Mg2+ concentration and phosphorylation of light-harvesting chlorophyll a/b-protein on various chlorophyll fluorescence induction parameters of isolated pea thylakoids was studied. Lowering the Mg2+ concentration from 3 to 0.4 mM decreases only the variable fluorescence (fv) and the area above the induction curve while at the same time increasing the slow exponential component of the rise (.***). A further decrease in Mg2+ concentration from 0.4 to 0 mM decreases the initial (f0) fluorescence level such that the ratio fv/fm increases slightly as does the area bove the induction curve and .***. Thylakoid membranes, phosphorylated at 5 mM Mg2+, show an equal decrease in fv and f0, no change in the area above the induction curve and an increase in .***. At 2 mM Mg2+, however, phosphorylation induced a more extensive quenching of fv so that the fv/fm ratio was lowered and the area above the induction curve decreased while .*** increased. When phosphorylated membranes were subsequently suspended in an Mg2+-free medium the effect of f0 due to phosphorylation was additive to that due to the absence of Mg2+. The effect of membrane phosphorylation on fluorescence is discussed in relation to the control of excitation energy distribution and shows that different mechanisms operate depending on the background Mg2+ levels. At high Mg2+ the phosphorylation seems to affect the absorption cross-section of Photosystem II while at lower Mg2+ levels there is an additional effect of increased spillover from Photosystem II to I.

关键词： Chlorophyll fluorescence Protein phosphorylation Mg 2+ effect Light-harvesting complex (Pea chloroplast) DCMU 3-(3,4-dichlorophenyl)-1,1-dimethylurea f m maximum chlorophyll fluorescence yield f 0 initial chlorophyll fluorescence yield f v = f m - f 0 (variable chlorophyll fluorescence yield) LHCP light-harvesting chlorophyll a b- protein Chl chlorophyll PS photosytem Tricine N -tris(hydroxymethyl)methylglycine

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DELAYED DIMETHYLfORMAMIDE BIOTRANSfORMATION AfTER HIGH EXPOSURES IN RATS

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TOXICOLOGY LETTERS 1983年第1-2期17卷 29-34页

作者： LUNDBERG, I PEHRSSON, A LUNDBERG, S KRONEVI, T LIDUMS, V NATL BOARD OCCUPAT SAFETY & HLTH S-17184 SOLNA SWEDEN

Rats were exposed to 2 dimethylformamide (DMf) air concentrations (2250 and 565 ppm for 4 h). Concentrations of DMf and the biotransformation product monomethylformamide (MMf) were measured in blood and some tissues at different times after the end of exposure. MMf concentrations 0 and 3 h after the end of the high exposure were generally lower than MMf concentrations at the same time after the low exposure. DMf biotransformation to MMf was delayed after the high exposure. As the hepatotoxic effect of DMf was correlated with MMf, this may have contributed to the previously observed slower appearance of hepatotoxicity after a high DME dose.

关键词： DMf dimethylformamide MMf monomethylformamide f formamide SDH sorbitol deny drogenase

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A HOMOPOLYMER Of THE POTENT ANTI-TUMOR DRUG 2'-DEOXY-5-fLUOROURIDYLATE

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BIOCHIMICA ET BIOPHYSICA ACTA 1983年第2期741卷 224-229页

作者： AMARNATH, V MILLER, TL BROOM, AD UNIV UTAH COLL PHARM DEPT MED CHEM SALT LAKE CITY UT 84112 USA

Poly(5-fluoro-2''-deoxyuridylic acid) was synthesized and its properties were compared with those of poly(dT) and poly(dU). It readily complexed with poly(dA). The 1:1 complex melted at about ***. C lower than poly(dA).***(dT). A triple-stranded helix, poly(dA).cntdot.2 poly(df5U) was formed only in high salt (2.0 M NaCl).

关键词： Antitumor drug Deoxyfluorouridylate Polynucleotide complex formation f 5 Ura 5-fluorouracil, df 5 Urd, 2′-deoxy-5-fluorouridine df 5 UMP 2′-deoxy-5-fluorouridylic acid poly(f 5 U) poly-(5-fluorouridylic acid) poly(df 5 U) poly(2′-deoxy-5-fluorouridylic acid) Mops 3-( N -morpholino)propanesulfonic acid Pipes piperazine- N , N ′-bis(2-ethanesulfonic acid)

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SERUM-PROTEINS Of WILD TURKEY VULTURES (CATHARTES-AURA)

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COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY 1983年第4期76卷 907-913页

作者： APANIUS, V TEMPLE, SA BALE, M UNIV WISCONSIN DEPT WILDLIFE ECOL MADISON WI 53706 USA UNIV WISCONSIN DEPT CHEM MADISON WI 53706 USA

The major serum proteins of turkey vultures (C. aura) were separated and identified: albumin, HDL [high density lipoproteins], LDL [low density lipoproteins], IgG and M, transferrin, .alpha.2M [.alpha.2 macroglobulin] and, putatively, IgA, ceruloplasmin and fibronectin. Turkey vulture HDL and LDL had similar electrophoretic mobility and solution properties as those from gallinaceous birds. Turkey vulture IgG and M, and their subunits, had MW comparable to other birds. Serum IgG and M levels in wild turkey vultures were within the range of values reported for domestic avian species.

关键词： α 2 M, α 2 macroglobulin Ig immunoglobulin BSA bovine serum albumin SDS sodium dodecyl sulfate M r apparent molecular weight (in kilodaltons) as determined by SDS-polyacrylamide electrophoresis R f relative mobility HDL high density lipoprotein LDL low density lipoprotein VLDL, very low density lipoprotein

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INTERACTIONS Of ACRIDINE-ORANGE WITH NUCLEIC-ACIDS - PROPERTIES Of COMPLEXES Of ACRIDINE-ORANGE WITH SINGLE STRANDED RIBONUCLEIC-ACID

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BIOCHEMICAL PHARMACOLOGY 1983年第24期32卷 3679-3694页

作者： KAPUSCINSKI, J DARZYNKIEWICZ, Z MELAMED, MR Memorial Sloan-Kettering Cancer Center New York NY 10021 United States

Interactions between acridine orange (AO) and nucleic acids (calf thymus DNA, and homoribopolynucleotides and homodeoxyribopolynucleotides) were studied in solutions containing ethanol as a cosolvent. Light absorption, scattering and luminescence were measured as a function of AO concentration at different dye/phosphate (D/P) ratios, and the data were analyzed using the McGhee-von Hippel probabilistic model of the polymer-ligand interactions. The absorption spectra of AO complexes with 4 homoribopolymers are presented. The intrinsic association constants and cooperativity coefficients of the formation of the complexes were calculated. The effects of ethanol (up to 35%, vol/vol) on these interactions were concentration dependent and may be extrapolated to 0 concentration of this cosolvent. The possibility of destabilization of the double helix of nucleic acids by AO at high D/P ratios is discussed in light of the available thermodynamic data.

关键词： AO 3,6-bis (dimethylamino)acridine hydrochloride = acridine orange ss single stranded ds, double stranded D/P, dye/phosphate molar ratio r , binding density n , binding site size ω, cooperativity coefficient K , association constant C f C B , free and bound dye concentrations E λ , molar extinction coefficient Δ G ° =- RTlnK, Gibbs free energy change and Hepes, 4- (2-hydroxyethyl)-1-piperazine-ethanesulfonic acid

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CHRONIC LYMPHOCYTIC-LEUKEMIA - A PROLIfERATIVE OR ACCUMULATIVE DISORDER

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LEUKEMIA RESEARCH 1983年第1期7卷 1-&页

作者： DORMER, P THEML, H LAU, B STADT KRANKENHAUS MUNCHEN MUNCHENFED REP GER

In two untreated patients with progressive CLL, quantitative 14C autoradiography of lymph nodes and, subsequently, continuous infusion of [3H] thymidine over eight and nine days, respectively, were performed in order to analyse the lymph node cell kinetics. Simultaneously, the turnover of labelled lymphocytes in the peripheral blood was evaluated. from another CLL patient a regional lymph node was removed 6 h after an intralymphatic flash injection of [3H] thymidine and sectioned for autoradiographic study of the distribution of labelled cells within the lymph node tissue. While the durations of DNA synthesis were found to be normal, the labelling indices were reduced. The relative cell production rate was far lower than normal. Very small growth fractions were calculated, amounting to less than 1% in one patient, and to 2.4% in the other. The distribution of labelled cells in the lymph nodes was focal, which supports the finding of low growth fractions. According to the present data, CLL is a disorder in which a very small number of cells cycle at a roughly normal rate. A kinetic definition of accumulative and proliferative tumour growth is introduced. Tumour growth is termed accumulative if growth appears to result from a decreased relative cell loss rate rather than an increased relative cell production rate. According to this definition, the kinetics in CLL may be classified as accumulative. In absolute terms, however, the number of lymphoid cells produced per unit of time was found to be far higher in CLL than in the healthy state.

关键词： Chronic lymphocytic leukemia proliferation kinetics growth fraction tumour growth CLL , chronic lymphocytic leukemia, TdR , thymidine WBC , white blood cells BM , bone marrow l s , DNA synthesis time K p , relative cell production rate (per 100 cells in the compartment), N S , relative number of cells in DNA synthesis (per 100 cells in the compartment) K L , relative rate of cell loss (per 100 cells in the compartment) K R , relative rate of lymphocyte release from lymph nodes (per 100 lymph node cells) K D , relative rate of cell death (per 100 lymph node cells) K l , relative rate of lymphocyte influx into the lymph node (per 100 lymph node cells) K f , relative rate of disappearance of lymphocytes from the peripheral blood (per 100 peripheral blood lymphocytes)

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MUTAGENIC ACTIVITY Of HETEROCYCLIC AMINES IN CHINESE-HAMSTER LUNG-CELLS WITH DIPHTHERIA-TOXIN RESISTANCE AS A MARKER

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MUTATION RESEARCH 1983年第1-2期118卷 91-102页

作者： NAKAYASU, M NAKASATO, f SAKAMOTO, H TERADA, M SUGIMURA, T National Cancer Center Research Institute I-I Tsukiji 5-chome Chuo-ku Tokyo 104 Japan

The mutagenicities of 8 heterocyclic amines, which were purified from pyrolysates of amino acids and proteins, broiled fish and fried beef, were assayed in Chinese hamster lung cells (CHL cells) in culture in the presence and absence of a metabolic activation system, with diphtheria toxin resistance as a selective marker. 3-Amino-1-methyl-5H-pyrido-[4,3-b]-indole (Trp-P-2) was the most mutagenic of the heterocyclic amines tested. 3-Amino-1,4-dimethyl-5H-pyrido-[4,3-b]-indole (Trp-P-1), 2-amino-3,4-dimethylimidazo-[4,5-f]-quinoline (MeIQ), 2-amino-3-methylimidazo-[4,5-f]-quinoline (IQ), 2-amino-9H-pyrido-[2,3-b]-indole (***.C), 2-amino-3,8-dimethylimidazo-[4,5-f]-quinoxaline (MeIQx), 2-amino-6-methyldipyrido-[1,2-a:3'',2''-d]-imidazole (Glu-P-1) and 2-aminodipyrido-[1,2-a:3'',2''-d]-imidazole (Glu-P-2) showed mutagenic activity on CHL cells, their specific activities being in the order shown above. All the compounds except Trp-P-1 required the presence of a metabolic activation system for mutagenicity on CHL cells. [This study may be applicable to carcinogenesis.].

关键词： Trp-P-1 3-amino-1,4-dimethyl-5 H -pyrido[4,3- b ]indole Trp-P-2 3-amino-1-methyl-5 H -pyrido[4,3- b ]indole Glu-P-1 2-amino-6-methyldipyrido[1,2- a :3′,2′- d ]imidazole Glu-P-2 2-aminodipyrido[1,2- a :3′,2′- d ]imidazole αC 2-Mamino-9 H -pyrido[2,3-b]indole IQ 2-amino-3-methylimidazo[4,5- f ]quinoline MeIQ 2-amino-3,4-dimethylimidazo[4,5- f ]quinoline MeIQx 2-amino-3,8-dimethylimidazo[4,5- f ]quinoxaline DMNA dimethylnitrosamine B[ a ]P, benzo[ a ]pyrene [ 14 C]NAD nicotinamide[U- 14 C]adenine dinucleotide DT r cells diphtheria toxin-resistant cells Ef-2 elongation factor 2 VAMEM Eagle's minimum essential medium supplemented with double concentrations of vitamins and amino acids fBS, fetal bovine serum

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STUDIES ON THE ANTIGENICITY AND CARBOHYDRATES Of HUMAN LOW-MOLECULAR WEIGHT KININOGEN

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MOLECULAR IMMUNOLOGY 1983年第12期20卷 1411-1418页

作者： TURPEINEN, U Department of Biochemistry Univeristy of Helsinki SF-00170 Helsinki 17 FinlandReceived 27 May 1983 Accepted 8 July 1983 Available online 12 November 2002

Native MW (LMr) kininogen from human plasma and a kinin-free kininogen from Cohn''s plasma fraction IV (HC-antigen) were isolated and studied with regard to their immunological reactivity and carbohydrate heterogeneity. Antisera were prepared against the conformational and sequence-dependence determinants of the H chain which is the common denominator of plasma kininogens. The molecules were characterized by single radial immunodiffusion and SDS [sodium dodecyl sulfate] gel electrophoresis. The effect of exoglycosidase treatment was investigated by a radioimmunoassay. The antigenic combining sites were not influenced by the partial removal of carbohydrates. These results suggest that the determinant structures of LMr kininogen reside in the peptide backbone of the protein. Carbohydrate heterogeneity was shown by different binding to concanavalin A and wheat germ lectin. With concanavalin A 52% of the immunoreactive HC-antigen was reactive compared to 76% of the native LMr kininogen. The weak reactivity (11%) of the HC-antigen towards the wheat germ lectin indicates that the N-acetylglucosamine residues are apparently blocked or missing. Immunoreactive kininogen was in all cases measured by single radial immunodiffusion or an RIA [radioimmunoassay]. The molecular nature of the heterogeneity is discussed in relation to the known isoelectric variations of kininogen.

关键词： Con A concanavalin A WGA wheat germ agglutinin HM λ high mol. wt LM λ low mol. wt EACA 6-aminocaproic acid H c -antigen kinin-free LM λ kininogen isolated from Cohn's plasma fraction IV SDS-PAGE sodium dodecyl sulfate-polycrylamide gel electrophoresis RCM reduced and carboxymethylated RIA radioimmunoassay PhMeSO 2 f phenylmethysulfonyl fluoride MeMan α-methyl-mannoside GlcNAc N -acetyglucosamine

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ULTRAVIOLET LIGHT-INDUCED MUTATION Of DIPLOID HUMAN-LYMPHOBLASTS

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MUTATION RESEARCH 1983年第2期107卷 347-370页

作者： DELUCA, JG WEINSTEIN, L THILLY, WG MIT DEPT NUTR & FOOD SCI TOXICOL GRP CAMBRIDGE MA 02139 USA

UV irradiation (254 nm) of immortal diploid human lymphoblasts killed cells, caused mutation at 3 genetic loci studied, and transiently inhibited 3H-TdR [H3-trifluorothymidine] uptake into DNA. A shoulder of about 6 J/m2 and a Do [mean lethal dose] of 6 J/m2 were observed for survival. Mutation rose in a monotonic nonlinear fashion through 6 J/m2;above 6 J/m2, complex behavior approximating a plateau in induced mutation was observed. Irradiation at 4.4 J/m2 caused a transient increase in the number of cells synthesizing DNA and a decrease in the rate of DNA synthesis relative to mock-irradiated controls. The parameter of rate of DNA synthesis per cell in DNA synthetic phase showed a rapid recovery toward control values between 2 and 4 h after irradiation and a slower recovery to control values by 22 h postirradiation. fractionated dose schedules were used to measure the effects of allowing a time interval between doses at nontoxic fluences (2.2 J/m2), moderately toxic fluences (8.8 J/m2) and toxic fluences (17.6 J/m2). These measurements indicate that, in the nontoxic range of fluences common to human exposure, mutational response is mediated by a postirradiation process which seems to show an enhanced ability to protect against mutation induced by subsequent irradiation. At moderatley toxic fluences there was little effect of dose fractionation, and, at toxic fluences, a time-dependent increase in mutation fraction was observed at separation times > 7 h. These latter observations arise primarily from cell cycle heterogeneity with regard to sensitivity to UV killing and mutation.

关键词： CfA clone-froming ability f 3 TdR trifluorothymidine fUdR fluorodexyuridine GCE growth curve extrapolation HGPRT hypoxanthine-guanine phosphoribosyl transferase IMf induced mutant fraction OUA ouabain PE plating efficiency S.E.M. standard error of mean TCA Trichloroacetic acid 6TG 6-thioguanine TK thymidine kinase UV 254 nm ultraviolet light XP xeroderma pigmentosum

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ENERGETICS Of PHOTOSYNTHESIS IN ZEA-MAYS .1. STUDIES Of THE fLASH-INDUCED ELECTROCHROMIC SHIfT AND fLUORESCENCE INDUCTION IN BUNDLE SHEATH-CELLS

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BIOCHIMICA ET BIOPHYSICA ACTA 1983年第1期722卷 116-126页

作者： LEEGOOD, RC CROWTHER, D WALKER, DA HIND, G UNIV SHEFFIELD DEPT BOT ARC PHOTOSYNTH RES GRP SHEFFIELD S10 2TN S YORKSHIRE ENGLAND BROOKHAVEN NATL LAB DEPT BIOL UPTON NY 11973 USA

Bundle sheath strands free of mesophyll contamination were isolated from 3-4 wk old leaves of maize (Z. mays L.). Patterns of electron flow in the preparations were studied in the presence of physiological substrates. Relative electron flow rates were estimated from the flash-induced electrochromic band shift changes (P-518) and cytochrome f turnover. Induction of chlorophyll fluorescence was also measured. Little photosystem [PS] II activity was present, the principal pathway of electron flow being PS I-driven cyclic electron transfer. The latter was activated through reductive poising by NADPH, generated via malate decarboxylation or (less efficiently) from dihydroxyacetone phosphate. The actions of these electron donors and of O2, nitrite and methyl viologen as electron acceptors in redox poising the PS I-driven cycle were investigated and are discussed in relation to the regulation of photosynthesis in the bundle sheath.

关键词： Photosynthesis Electron transport Photosystem I Chlorophyll fluorescence fluorescence induction (Zea mays bundle sheath cell) DCMU, 3-(3,4-dichlorophenyl)-1, 1-dimethylurea Hepes, N -2-hydroxyethylpiperazine- N ′-2-ethanesulphonic acid Tricine, N -tris(hydroxymethyl)methylglycine PVP, polyvinylpyrrolidone DBMIB, 2,5-dibromo-3-methyl-6-isopropylbenzoquinone DNP-INT, 2,4-dinitrophenyl ether of iodonitrothymol f 0 , intrinsic bed fluorescence f i , initial level of fluorescence seen during rapid induction ( f 0 plus a variable component proportional to the state of reduction of Q) f m , maximum level of fluorescence (seen in the presence of DCMU) f v , variable fluorescence (maximally f m - f 0 ) Chl, chlorophyll PS, photosystem

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