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Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Studies Of Transketolase Abnormality In Alzheimer's Disease / Kwan-Fu Rex Sheu, Phd; Donald D. Clarke, Phd; Young-Tai Kim, Phd; John P. Blass, Md, Phd; Bradford J. Harding; Joseph Decicco, Kwan-Fu Rex Sheu, Donald Dudley Clarke Phd, Young-Tai Kim, John P. Blass Jan 1988

Studies Of Transketolase Abnormality In Alzheimer's Disease / Kwan-Fu Rex Sheu, Phd; Donald D. Clarke, Phd; Young-Tai Kim, Phd; John P. Blass, Md, Phd; Bradford J. Harding; Joseph Decicco, Kwan-Fu Rex Sheu, Donald Dudley Clarke Phd, Young-Tai Kim, John P. Blass

Chemistry Faculty Publications

The partially purified transketolase from each of eight well-nourished patients with Alzheimer's disease contained significantly less heat-stable component with a significantly longer half-life of heat inactivation than that from eight controls. Immunochemical studies utilizing antibodies to the purified human liver transketolase did not distinguish between red blood cell transketolases of patients with Alzheimer's disease and those of controls. However, three brains from patients with Alzheimer's disease that were deficient in transketolase activity lacked a 69-kilodalton form on immunoblots. Subtle structural abnormalities of transketolase appear to occur in a high proportion of patients with Alzheimer's disease


Pyrimidines. 9. Chlorination Of 6-Trifluoromethyluracil With Phosphorus Oxychloride In The Presence Of Trialkylamines / Herman Gershon [Ab], Anthony T. Grefig [A], And Donald D. Clarke [B] [A] Boyce Thompson Institute For Plant Research At Cornell University, Ithaca, New York 14853 [B] Department Of Chemistry, Fordham University, Bronx, New York 10458, Herman Gershon, Anthony T. Grefig, Donald Dudley Clarke Phd Jan 1987

Pyrimidines. 9. Chlorination Of 6-Trifluoromethyluracil With Phosphorus Oxychloride In The Presence Of Trialkylamines / Herman Gershon [Ab], Anthony T. Grefig [A], And Donald D. Clarke [B] [A] Boyce Thompson Institute For Plant Research At Cornell University, Ithaca, New York 14853 [B] Department Of Chemistry, Fordham University, Bronx, New York 10458, Herman Gershon, Anthony T. Grefig, Donald Dudley Clarke Phd

Chemistry Faculty Publications

Ring-chlorination of 6-trifluoromethyluracil in phosphorus oxychloride in the presence of triethyl, tri-npropyl, and tri-n-butylamines was studied with respect to by-product formation. Comparisons were made with the results obtained by treating the preformed chlorinated pyrimidine with triethyl amine in boiling toluene. Amination of chloropyrimidines by tertiary amines takes place by a Hofmann type reaction with substituent orientation generally in the 2 position of the ring. Yields of products depended on the base and reaction time. The rate of substitution in the 2 position is significantly enhanced by the presence of the trifluoromethyl group in the 6 position as compared with a ...


Pyrimidines. 8. Chlorination Of 6-Methyluracil With Phosphorus Oxychloride In The Presence Of Trialkyamines / Herman Gershon [Ab], Anthony T. Grefig [A], And Donald D. Clarke [B] [A] Boyce Thompson Institute For Plant Research At Cornell University, Ithaca, New York 14853 [B] Department Of Chemistry, Fordham University, Bronx, New York 10458, Herman Gershon, Anthony T. Grefig, Donald Dudley Clarke Phd Jan 1987

Pyrimidines. 8. Chlorination Of 6-Methyluracil With Phosphorus Oxychloride In The Presence Of Trialkyamines / Herman Gershon [Ab], Anthony T. Grefig [A], And Donald D. Clarke [B] [A] Boyce Thompson Institute For Plant Research At Cornell University, Ithaca, New York 14853 [B] Department Of Chemistry, Fordham University, Bronx, New York 10458, Herman Gershon, Anthony T. Grefig, Donald Dudley Clarke Phd

Chemistry Faculty Publications

The effect of the tertiary amines triethyl, tri-n-propyl, and tri-n-butylamines on the chlorination of 6-methyluracil by phosphorus oxychloride was studied. A comparison with the reaction of preformed 2,4-dichloro-6-methylpyrimidine and triethylamine in toluene was made. The reaction in phosphorus oxychloride in the presence of triethylamine afforded low yields of 2-diethylamino derivative after short heating periods and high yields of the 2,4-bis(diethylamino) derivative after 188 hours of boiling. Heating the preformed 2,4-dichloro-6-methylpyrimidine in toluene in the presence of triethylamine yielded primarily the 2-diethylaminopyrimidine along with a small amount of the 4-diethylamino isomer. After 188 hours, the product mixture ...


Acetylation Of Synaptosomal Protein: Effect Of Na+ / Arlene Colon, Soll Berl, And Donald D. Clarke, Arlene D. Colon, Soll Berl, Donald Dudley Clarke Phd Jan 1987

Acetylation Of Synaptosomal Protein: Effect Of Na+ / Arlene Colon, Soll Berl, And Donald D. Clarke, Arlene D. Colon, Soll Berl, Donald Dudley Clarke Phd

Chemistry Faculty Publications

In a previous study it was shown that the acetyl moiety can be incorporated into the protein of purified synaptosomes (1). This process was inhibited by veratridine and the inhibitory effect was counteracted by tetrodotoxin. This suggested that the flux ofNa +may be related to the acetylation process. We now report that in a sodium free medium the amount of acetylation is increased and the inhibitory effect of veratridine (veratrine) is no longer evident. The addition ofNa +leads to a decrease in acetylation in the presence of veratrine. The presence of scorpion toxin has an effect similar to that of ...


Purification And Characterization Of A Soluble And A Particulate Glutamate Dehydrogenase From Rat Brain / Arlene D. Colon, Andreas Plaitakis, Antonis Perakis, Soll Berl, And Donald D. Clarke Department Of Neurology, Mount Sinai School Of Medicine, New York, And Department Of Chemistry, Fordham University, Bronx, New York, U.S.A., Arlene D. Colon, Andreas Plaitakis, Antonis Perakis, Donald Dudley Clarke Phd Jan 1986

Purification And Characterization Of A Soluble And A Particulate Glutamate Dehydrogenase From Rat Brain / Arlene D. Colon, Andreas Plaitakis, Antonis Perakis, Soll Berl, And Donald D. Clarke Department Of Neurology, Mount Sinai School Of Medicine, New York, And Department Of Chemistry, Fordham University, Bronx, New York, U.S.A., Arlene D. Colon, Andreas Plaitakis, Antonis Perakis, Donald Dudley Clarke Phd

Chemistry Faculty Publications

Glutamate dehydrogenase (GDH) activity was determined in high-speed fractions (1 00,000 g for 60 min) obtained from whole rat brain homogenates after removal of a low-speed pellet (480 g for 10 min). Approximately 60% of the high-speed GDH activity was particulate (associated with membrane) and the remaining was soluble (probably of mitochondrial matrix origin). Most of the particulate GDH activity resisted extraction by several commonly used detergents, high concentration of salt, and sonication; however, it was largely extractable with the cationic detergent cetyltrimethylammonium bromide (CTAB) in hypotonic buffer solution. The two GDH activities were purified using a combination of ...


The Subcellular Localization Of Glutamate Dehydrogenase (Gdh): Is Gdh A Marker For Mitochondria In Brain? / James C. K. Lai, Kwan-Fu Rex Sheu, Young Tai Kim, Donald D. Clarke, And John P. Blass Department Of Neurology, Cornell University Medical College And Altschul Laboratory For Dementia Research Burke Rehabilitation Center White Plains, Ny 10605 And Department Of Medicine Cornell University Medical College New York, Ny 10021, James C. K. Lai, Kwan-Fu Rex Sheu, Young Tai Kim, Donald Dudley Clarke Phd Jan 1986

The Subcellular Localization Of Glutamate Dehydrogenase (Gdh): Is Gdh A Marker For Mitochondria In Brain? / James C. K. Lai, Kwan-Fu Rex Sheu, Young Tai Kim, Donald D. Clarke, And John P. Blass Department Of Neurology, Cornell University Medical College And Altschul Laboratory For Dementia Research Burke Rehabilitation Center White Plains, Ny 10605 And Department Of Medicine Cornell University Medical College New York, Ny 10021, James C. K. Lai, Kwan-Fu Rex Sheu, Young Tai Kim, Donald Dudley Clarke Phd

Chemistry Faculty Publications

Glutamate dehydrogenase (GDH, EC 1.4.1.2) has long been used as a marker for mitochondria in brain and other tissues, despite reports indicating that GDH is also present in nuclei of liver and dorsal root ganglia. To examine whether GDH can be used as a marker to differentiate between mitochondria and nuclei in the brain, we have measured GDH by enzymatic activity and on immunoblots in rat brain mitochondria and nuclei which were highly enriched by density-gradient centrifugation methods. The activity of GDH was enriched in the nuclear fraction as well as in the mitochondrial fraction, while the ...


Acetylation-Deacetylation Of Synaptosomal Proteins: Effect Of Na+ / S. Berl, A. Colon And D. D. Clarke. Mt. Sinai School Of Medicine, New York, N.Y. 10029, Soll Berl, Arlene D. Colon, Donald Dudley Clarke Phd Jan 1985

Acetylation-Deacetylation Of Synaptosomal Proteins: Effect Of Na+ / S. Berl, A. Colon And D. D. Clarke. Mt. Sinai School Of Medicine, New York, N.Y. 10029, Soll Berl, Arlene D. Colon, Donald Dudley Clarke Phd

Chemistry Faculty Publications

Synaptosomes (S) when incubated with 3H-acetate (HA), are rapidly labeled. The perchloric acid (PCA) precipitable proteins contain most of the radioactivity probably as the acetyl moiety, which is released in a volatile form after acid or base hydrolysis (Berl et al., - J. Neurochem. 40:176, 1983). Much of the radioactivity was chased by addition of unlabeled acetate suggesting that the acetylation was reversible. Labeling was also decreased in the presence of veratridine/veratrine (V, 100uPt!) and this effect was prevented by tetrodotoxin (2uM). When Na was omitted from the incubation medium, the incorporation of (HA) was increased; however, the effect ...


Cerebral Glutamine/Glutamate Interrelationships And Metabolic Compartmentation / S. Berl And D. D. Clarke, Soll Berl, Donald Dudley Clarke Phd Jan 1984

Cerebral Glutamine/Glutamate Interrelationships And Metabolic Compartmentation / S. Berl And D. D. Clarke, Soll Berl, Donald Dudley Clarke Phd

Chemistry Faculty Publications

The fact that in animals the concentration of glutamate and glutamine are higher in brain than in any other tissue initially attracted interest in attempting to understand the function or functions of these amino acids in the central nervous system. They were evidently required for protein synthesis and early studies established their close relationship to the Krebs tricarboxylic acid cycle and energy metabolism in brain. Glutamine formation in brain was also shown to be sensitive to elevations in plasma ammonia levels and to serve as the primary method for detoxifying this substance in brain in contrast to urea formation in ...


Potassium 1,3,3a,8a-Tetrahydro-3a,8a-Dihydroxy-2,8-Dioxoindeno[1,2-D]Imidazole-2-Ethanesulfonate, K+.C12h11n2o7s- / By D. D. Bray And D. D. Clarke Chemistry Department, Fordham University, Bronx, Nyew York 10458, Usa And N. Chatterjie And B. Sinha Institute For Basic Research In Development Disabilities, 1050 Forest Hill Road, Staten Island, New York 10314, Usa, Diana Bray, Donald Dudley Clarke Phd, Nithiananda Chatterjie, B. Sinha Jan 1984

Potassium 1,3,3a,8a-Tetrahydro-3a,8a-Dihydroxy-2,8-Dioxoindeno[1,2-D]Imidazole-2-Ethanesulfonate, K+.C12h11n2o7s- / By D. D. Bray And D. D. Clarke Chemistry Department, Fordham University, Bronx, Nyew York 10458, Usa And N. Chatterjie And B. Sinha Institute For Basic Research In Development Disabilities, 1050 Forest Hill Road, Staten Island, New York 10314, Usa, Diana Bray, Donald Dudley Clarke Phd, Nithiananda Chatterjie, B. Sinha

Chemistry Faculty Publications

Mr = 366·40, monoclinic, P2/c, Z = 4, a=6·195 (1), b= 17·701 (4), c= 1.2·864 (3)A, P= 116·25(2)0 , V=l387·8A3, Dm=1·74, Dx= 1·754 Mg m-3, CuKa, l = 1·5418 A, ,u = 5·07 mm-1, T= 298 K, F(OOO) = 752, R = 0·074 for 2091 observed independent intensity data. Crystals were prepared by reacting the K salt of ureidotaurine with ninhydrin in acid solution. The product shows that the unsubstituted N -of the ureidotaurine reacts with the central C of ninhydrin


Acetylation Of Synaptosomal Protein: Inhibition Of Veratridine / Soll Berl, Ramiro Nunez, Arlene D. Colon, And Donald D. Clarke Mount Sinai School Of Medicine, And Chemistry Department, Fordham University, New York, New York, U.S.A., Soll Berl, Ramiro Nunez, Arlene D. Colon, Donald Dudley Clarke Phd Jan 1983

Acetylation Of Synaptosomal Protein: Inhibition Of Veratridine / Soll Berl, Ramiro Nunez, Arlene D. Colon, And Donald D. Clarke Mount Sinai School Of Medicine, And Chemistry Department, Fordham University, New York, New York, U.S.A., Soll Berl, Ramiro Nunez, Arlene D. Colon, Donald Dudley Clarke Phd

Chemistry Faculty Publications

Incubation of synaptosomes with [3H]acetate results in rapid labeling of protein. Labeling is decreased in the presence of veratridine, and the effect of veratridine is blocked by tetrodotoxin. Most of the radioactivity can be removed by base or acid hydrolysis, and is probably incorporated as acetate; it is this fraction that is affected by the veratridine. The data suggest that veratridine stimulates deacetylation of synaptosomal protein. This raises the question whether acetylation-deacetylation is involved in membrane function


The Metabolic Compartmentation Concept / S. Berl And D. D. Clarke Mt. Sinai School Of Medicine, Bronx, N.Y. 10458; Department Of Chemistry, Fordham University, New York, N.Y. 10029., Soll Berl, Donald Dudley Clarke Phd Jan 1983

The Metabolic Compartmentation Concept / S. Berl And D. D. Clarke Mt. Sinai School Of Medicine, Bronx, N.Y. 10458; Department Of Chemistry, Fordham University, New York, N.Y. 10029., Soll Berl, Donald Dudley Clarke Phd

Chemistry Faculty Publications

The concept of metabolic compartmentation describes the presence in a tissue of functionally different and chemically distinct pools of a given substrate. These separate pools equilibrate only very slowlyt if at a11, and exhibit different turnover and flux rates. Such heterogeneous functional pools of amino acids were coming under investigation in microorganisms (Britten et al. 1955; Cowie, Walton 1956; Cowie, McClure 1959), plants (Steward et al. 1956; Maclennan et al. 1963), and animal tissues (Korner, Tarver 1957; Green, Lowther 1959; Kipnis et al. 1961) at about the same time that we began our studies on glutamate-glutamine metabolism in brain. The ...


Fluoroacetate As A Possible Marker For Glial Metabolism In Vivo / Donald D. Clarke, Ph.D. And Soll Berl, M. D. Dept. Of Chemistry, Fordham Univ. And Dept. Of Neurology, Mt. Sinai School Of Medicine Bronx, N.Y. 10458 And New York, N.Y. 10029, Donald Dudley Clarke Phd, Soll Berl, Donald Dudley Clarke Phd Jan 1983

Fluoroacetate As A Possible Marker For Glial Metabolism In Vivo / Donald D. Clarke, Ph.D. And Soll Berl, M. D. Dept. Of Chemistry, Fordham Univ. And Dept. Of Neurology, Mt. Sinai School Of Medicine Bronx, N.Y. 10458 And New York, N.Y. 10029, Donald Dudley Clarke Phd, Soll Berl, Donald Dudley Clarke Phd

Chemistry Faculty Publications

Glucose is the major source of energy in all brain cells and its metabolism is closely coupled to functional activity. Advantage has been taken of this by Sokoloff (1977) and Sokoloff et al. (1977) to study energy metabolism in different brain areas and their response to a variety of drugs and stimuli. For this purpose these workers have developed the procedure for mrasuring autoradiographically the accumulation of [14C]-deoxyglucose into its phosphate derivative, a compound which does not differentiate glial from neuronal metabolism. They could be enhanced if one could differentiate glial from neuronal metabolic response to the various experimental ...


Oxidative Metabolism Of 4-Aminobutyrate By Rat Brain Mitochondria: Inhibition By Branched-Chain Fatty Acid / J. Cunningham, D. D. Clarke, And W.J. Nicklas, J. Cunningham, Donald Dudley Clarke Phd, William J. Nicklas Jan 1980

Oxidative Metabolism Of 4-Aminobutyrate By Rat Brain Mitochondria: Inhibition By Branched-Chain Fatty Acid / J. Cunningham, D. D. Clarke, And W.J. Nicklas, J. Cunningham, Donald Dudley Clarke Phd, William J. Nicklas

Chemistry Faculty Publications

The oxidation of 4-aminobutyric acid (GABA) by nonsynaptosomal mitochondria isolated from rat forebrain and the inhibition of this metabolism by the branched-chain fatty acids 2-methyl-2-ethyl caproate (MEC) and 2,2- dimethyl valerate (DMV) were studied. The rate of GABA oxidation, as measured by 02 uptake, was determined in medium containing either 5 or 100 mM-[K+]. The apparent Km for GABA was 1.16 ± 0.19 mM and the Vmax in state 3 was 23.8 + 5.5 ng-atoms O2 ·min-1.mg protein-1 in 5 mM-[K+]. In a medium with 100 mM-[K+] the apparent K111 was 1.11 ...


Synthesis Of 2-Aminomorphine And 2-Aminocodeine. Reduction Of Aromatic Nitro Groups With Formamidinesulfinic Acid. / Nithiananda Chatterjie, Arlene Minar And Donald D. Clarke New York State Institute For Basic Research In Mental Retardation, Staten Island, Ny 10314, Nithiananda Chatterjie, Arlene Minar, Donald Dudley Clarke Phd Jan 1979

Synthesis Of 2-Aminomorphine And 2-Aminocodeine. Reduction Of Aromatic Nitro Groups With Formamidinesulfinic Acid. / Nithiananda Chatterjie, Arlene Minar And Donald D. Clarke New York State Institute For Basic Research In Mental Retardation, Staten Island, Ny 10314, Nithiananda Chatterjie, Arlene Minar, Donald Dudley Clarke Phd

Chemistry Faculty Publications

Our interest in the stereoselective reduction of the carbonyl groups of various oxymorphone derivatives with formamidinesulfinic acid (FSA) led to a result indicating that dihydrocodeinone underwent ring-oxygen scission under the conditions of reduction with this reagent. This observation4 has prompted interest and speculation as to the scope and mechanism of this reaction by others, as well as ourselves


Glial Cells And Metabolic Compartmentation / S. Berl, W.J. Nicklas, And D.D. Clarke Dept. Of Neurology, Mt. Sinai School Of Medicine, N.Y., N.Y. 10029 Dept. Of Chemistry, Fordham University, N.Y. 10458, U.S.A., Soll Berl, William J. Nicklas, Donald Dudley Clarke Phd Jan 1978

Glial Cells And Metabolic Compartmentation / S. Berl, W.J. Nicklas, And D.D. Clarke Dept. Of Neurology, Mt. Sinai School Of Medicine, N.Y., N.Y. 10029 Dept. Of Chemistry, Fordham University, N.Y. 10458, U.S.A., Soll Berl, William J. Nicklas, Donald Dudley Clarke Phd

Chemistry Faculty Publications

The study of metabolic compartmentation in brain has been under investigation for some twenty years. Most interpretations of the data have focused on attempts to assess the relative contributions of glia and neurons to the metabolic pictures since anatomically and functionally they are distinct. It is very probable that these cell types contain other metabolic compartments based on anatomic and subcellular subdivisions. However, the presently available experimental data is insufficient to specify precisely the total number of such metabolic pools functioning in nervous tissue. The initial observations that set in motion most of the work were a) in the adult ...


Amino Acid Analogs Iv: 4-Fluoroisoleucine / Herman Gershon, Larry Shanks, And Donald D. Clark, Herman Gershon, Larry Shanks, Donald Dudley Clarke Phd Jan 1978

Amino Acid Analogs Iv: 4-Fluoroisoleucine / Herman Gershon, Larry Shanks, And Donald D. Clark, Herman Gershon, Larry Shanks, Donald Dudley Clarke Phd

Chemistry Faculty Publications

4-Fluoroisoleucine was produced by ammonolysis of 2- bromo-4-fluoro-3-methylpentanoic acid, which resulted from the bromofluorination of 4-methyl-2-pentenoic acid. It did not inhibit Plasmodium berghei in mice at 640 mg/kg and was not toxic to the animals. The fluoroamino acid inhibited Aspergillus niger, Trichoderma viride, Myrothecium verrucaria, Trichophyton mentagrophytes, and Mucor mucedo in Czapek solution agar at a concentration between 104 and 103 μg/ml. Growth of Escherichia coli was inhibited 25% at 900 μg/ml in a defined medium


A Relationship Of N-Acetylaspartate Biosynthesis To Neuronal Protein Synthesis / D. D. Clarke, S. Greenfield, E. Dicker, L.J. Tirri, And E.J. Ronan Chemistry Department, Fordham University, Bronx, Ny 10458, U.S.A., Donald Dudley Clarke Phd, S. Greenfield, E. Dicker, L. J. Tirri Jan 1975

A Relationship Of N-Acetylaspartate Biosynthesis To Neuronal Protein Synthesis / D. D. Clarke, S. Greenfield, E. Dicker, L.J. Tirri, And E.J. Ronan Chemistry Department, Fordham University, Bronx, Ny 10458, U.S.A., Donald Dudley Clarke Phd, S. Greenfield, E. Dicker, L. J. Tirri

Chemistry Faculty Publications

A detailed time study of the incorporation of label from sodium-[1-14C]acetate, [1-14C]ethanol, and [2-14C]glucose into the aspartyl moiety of N-acetylaspartic acid (NAA) was conducted. As expected the specific activity of aspartate increased rapidly with time and peaked within 15-20 min after which it fell sharply: but significantly that of the aspartyl moiety of NAA rose very slowly even after the specific activity of aspartate had fallen to less than 1 per cent of the peak values. A rat brain microsomal free supernatant preparation was shown enzymatically to incorporate label from sodium-[l-14C]acetate into the t-RNA ...


Interaction Of Catecholamine And Amino Acid Metabolism In Brain: Effect Of Pargyline And L-Dopa / W. J. Nicklas, S. Berl, And D. D. Clarke Department Of Neurology, College Of Physicians And Surgeons, Columbia University, 640 West 168th Street, New York, Ny 10032 And Department Of Chemistry, Fordham University, Bronx, Ny 10458, U.S.A., Soll Berl, William J. Nicklas, Donald Dudley Clarke Phd Jan 1974

Interaction Of Catecholamine And Amino Acid Metabolism In Brain: Effect Of Pargyline And L-Dopa / W. J. Nicklas, S. Berl, And D. D. Clarke Department Of Neurology, College Of Physicians And Surgeons, Columbia University, 640 West 168th Street, New York, Ny 10032 And Department Of Chemistry, Fordham University, Bronx, Ny 10458, U.S.A., Soll Berl, William J. Nicklas, Donald Dudley Clarke Phd

Chemistry Faculty Publications

The combination of L-DOPA and pargyline caused a decrease in level of aspartate and an increase in that of glutamine in vivo in cerebral cortex, cerebellum, brain stem, hypothalamus, neostriatum and cervical cord of rat. There was also a decreased incorporation of radioactivity from [1-14C]acetate into amino acids in rico, most notably in cerebellum and brain stem. The labelling of glutamine was especially affected. In addition, cortical slices were prepared from guinea pigs which had been pretreated with pargyline. These slices were incubated with and without 1 mM L-DOPA in media containing [l- 14C]acetate. Pargyline alone caused a ...


Isolation And Stereochemical Identification Of A Metabolite Of Naltrexone From Human Urine / Nithiananda Chatterjie, James M. Fujimoto, Charles E. Inturrisi, Sandra Reorig, Richard I.H. Wang, David V. Bowen, Frank H. Field, And Donald D. Clarke Department Of Pharmacology, Cornell University Medical College (N.C., C.E.I.), Department Of Pharmacology, Medical College Of Wisconsin (J.M.F., S.R.), Veterans Administrative Center, Wood, Wisconsin (R.I.H.W.), Mass Spectrometry Service Laboratory, The Rockefeller University (D.V.B., F.H.F.), And Department Of Chemistry, Fordham University (D.D.C.), Nithiananda Chatterjie, James M. Fujimoto, Charles E. Inturrisi, Donald Dudley Clarke Phd Jan 1974

Isolation And Stereochemical Identification Of A Metabolite Of Naltrexone From Human Urine / Nithiananda Chatterjie, James M. Fujimoto, Charles E. Inturrisi, Sandra Reorig, Richard I.H. Wang, David V. Bowen, Frank H. Field, And Donald D. Clarke Department Of Pharmacology, Cornell University Medical College (N.C., C.E.I.), Department Of Pharmacology, Medical College Of Wisconsin (J.M.F., S.R.), Veterans Administrative Center, Wood, Wisconsin (R.I.H.W.), Mass Spectrometry Service Laboratory, The Rockefeller University (D.V.B., F.H.F.), And Department Of Chemistry, Fordham University (D.D.C.), Nithiananda Chatterjie, James M. Fujimoto, Charles E. Inturrisi, Donald Dudley Clarke Phd

Chemistry Faculty Publications

Pooled urine samples from patients receiving 100-200 mg of naltrexone per day orally were extracted; the basic (alkaloid) compounds derived were isolated by preparative thin-layer chromatography. The major metabolite of naltrexone was found to be an epimer of N-cyclopropylmethyl- 14-hydroxy-7,8-dihydronormorphine wherein the 6-keto group of naltrexone had been reduced to yield the 6β-hydroxy epimer (an isomorphine). This conclusion was based on infrared, mass, and nuclear magnetic resonance spectra studies. Furthermore, the reduction product formed in vitro in a soluble chicken liver enzyme system from naltrexone and an in vivo metabolite of naloxone derived from the chicken were found to ...


Alteration In The Expression Of Compartmentation: In Vitro Studies / D. D. Clarke And S. Berl, Donald Dudley Clarke Phd, Soll Berl Jan 1972

Alteration In The Expression Of Compartmentation: In Vitro Studies / D. D. Clarke And S. Berl, Donald Dudley Clarke Phd, Soll Berl

Chemistry Faculty Publications

Glutamic acid and glutamine are present in unusually large concentrations in brain. The only known enzymatic mechanism which has been reported for the synthesis of glutamine is that catalysed by glutamine synthetase (E.C.6.3.1.2). These amino acids provide a very useful probe for studying precursor-product relationships in brain tissue in vivo. It is evident that the non-steady state situation presented by injection of a single dose of inhibitor followed by a tracer dose of a labelled precursor at some later time-a practice which has been used extensively in previous attempts to clarify the effects of metabolic ...


Effects Of Li+ On The Metabolism In Brain Of Glutamate, Glutamine, Aspartate And Gaba From [I-14]Acetate In Vitro / S. Berl And D. D. Clarke Department Of Neurology, College Of Physicians And Surgeons, Columbia University, New York, N.Y. 10032 And Chemistry Department, Fordham University, Bronx, N.Y. 10458 (U.S.A.), Soll Berl, Donald Dudley Clarke Phd Jan 1972

Effects Of Li+ On The Metabolism In Brain Of Glutamate, Glutamine, Aspartate And Gaba From [I-14]Acetate In Vitro / S. Berl And D. D. Clarke Department Of Neurology, College Of Physicians And Surgeons, Columbia University, New York, N.Y. 10032 And Chemistry Department, Fordham University, Bronx, N.Y. 10458 (U.S.A.), Soll Berl, Donald Dudley Clarke Phd

Chemistry Faculty Publications

Guinea pig brain slices were incubated in media in which Li+ replaced part of the Na+. Leakage of glutamic acid, glutamine, aspartic acid and GABA into the media were increased markedly; glutamic acid was most affected. The uptake of [1-14C]acetate was decreased in the presence of Li+. Of the amino acids related to the citric acid cycle the labeling of glutamine was most affected. The presence of 100% O2 counteracts in part the Li+ effects. The results were interpretable on the basis of the compartmentation of citric acid cycle metabolism in brain. It is suggested that the pool of ...


Ultraviolet-Stimulated Thymidine Incorporation In Xeroderma Pigmentosum Lymphocytes / Peter G. Burk Marvin A. Lutzner Donald D. Clarke And Jay H. Robbins Bethesda, Md And Bronx, N.Y. From The Dermatology Branch, National Cancer Institute, National Institutes Of Health And The Chemistry Department, Fordham University, Peter G. Burk, Marvin A. Lutzner, Donald Dudley Clarke Phd, Jay H. Robbins Jan 1971

Ultraviolet-Stimulated Thymidine Incorporation In Xeroderma Pigmentosum Lymphocytes / Peter G. Burk Marvin A. Lutzner Donald D. Clarke And Jay H. Robbins Bethesda, Md And Bronx, N.Y. From The Dermatology Branch, National Cancer Institute, National Institutes Of Health And The Chemistry Department, Fordham University, Peter G. Burk, Marvin A. Lutzner, Donald Dudley Clarke Phd, Jay H. Robbins

Chemistry Faculty Publications

Autoradiographic and liquid scintillation counting techniques were utilized to measure the ultraviolet (UV)-stimulated incorporation of radioactive thymidine during repair replication of the UV-damaged deoxyribonucleic acid (DNA) of irradiated peripheral blood lymphocytes from 4 patients w ith xeroderma pigmentosum (XDP) and from normal donors. Lymphocytes from 3 of the 4 patients had a markedly decreased rate of incorporation soon after irradiation in comparison with the rate obtained with normal donors' lymphocytes. However, the duration of incorporation into these 3 patients' lymphocytes was prolonged, so that XDP lymphocytes appear eventually to incorporate as much total thymidine as normal lymphocytes. Lymphocytes from ...


Compartmentation Of Glutamate Metabolism Observed With Glucose / D. D. Clarke, E. Dicker & E.J. Ronan, Chem. Dept. Fordham University, Bronx, N.Y. 10458, U.S.A., Donald Dudley Clarke Phd, E. Dicker, E. J. Ronan Jan 1970

Compartmentation Of Glutamate Metabolism Observed With Glucose / D. D. Clarke, E. Dicker & E.J. Ronan, Chem. Dept. Fordham University, Bronx, N.Y. 10458, U.S.A., Donald Dudley Clarke Phd, E. Dicker, E. J. Ronan

Chemistry Faculty Publications

Compartmentation of glutamate metabolism in the central nervous system has been demonstrated in a number of laboratories using a variety of labeled precursors. The labeling of glutamine is much more rapid than would be expected if the total pool of glutamate in brain is the precursor of glutamine. An obvious suggestion for the origin of this compartmentation is that it reflects glial vs. neuronal relationships. Some evidence in support of this idea has been obtained by Rose using separated neuronal vs. neuropil preparations (J. Neurochem. 17, 809 (1970)). Until recently orain was the only tissue which, after the injection of ...


Decarboxylation Studies Of Glutamate, Glutamine, And Aspartate From Brain Labelled With [I-14]Acetate, L-[U-14c]-Aspartate, And L-[U-14c]Glutamate / W.J. Nickls And D. D. Clarke Chemistry Department, Fordham University, Bronx, N.Y. And S. Berl Department Of Neurology, College Of Physicians And Surgeons, Columbia University, New York, N.Y., William J. Nicklas, Donald Dudley Clarke Phd, Soll Berl Jan 1969

Decarboxylation Studies Of Glutamate, Glutamine, And Aspartate From Brain Labelled With [I-14]Acetate, L-[U-14c]-Aspartate, And L-[U-14c]Glutamate / W.J. Nickls And D. D. Clarke Chemistry Department, Fordham University, Bronx, N.Y. And S. Berl Department Of Neurology, College Of Physicians And Surgeons, Columbia University, New York, N.Y., William J. Nicklas, Donald Dudley Clarke Phd, Soll Berl

Chemistry Faculty Publications

Studies in vivo and in vitro of the distribution of label in C-1 of glutamate and glutamine and C-4 of aspartate in the free amino acids of brain were carried out. [1-14C]Acetate was used both in vivo and in vitro and L-[U-14C]aspartate and L-[U-14C]glutamate were used in vitro. (1) The results obtained with labelled acetate and aspartate suggest that CO2 and a 3-carbon acid may exchange at different rates on a CO2-fixing enzyme. (2) The apparent cycling times of both glutamate and glutamine show fast components measured in minutes and slow components measured in hours ...


The Nature Of The "Contractile" Protein Isolated From Brain / S. Puszkin, E. Puszkin, D. D. Clarke, And S. Berl. Coll Of Phys. And Surgeons., Columbia Univ., N.Y. 10032, S. Puszkin, E. Puszkin, Donald Dudley Clarke Phd, Soll Berl Jan 1969

The Nature Of The "Contractile" Protein Isolated From Brain / S. Puszkin, E. Puszkin, D. D. Clarke, And S. Berl. Coll Of Phys. And Surgeons., Columbia Univ., N.Y. 10032, S. Puszkin, E. Puszkin, Donald Dudley Clarke Phd, Soll Berl

Chemistry Faculty Publications

We have described the isolation from brain of a Mg++/Ca++-ATPase resembling muscle actomyosin (Sci. 12 1 1701 1968). Like myofibrils (Perry and Grey 1 Biochem. J. 64, 184, 1956), the ATPase activity isolated from rat and cat brain is dependent upon the cone. of ATP and cation. When the conc. of ATP exceeds that of Mg++ 1 enzyme activity is inhibited. With increasing conc. of Mg++ 1 the optimum conc. of ATP also increases. This does not occur with Ca++ . Polyethylenesulfonate( PS)(I0-6M)causes the splitting of actomyosin into actin and myosin; the Mg++-ATPose activity is correspondingly ...


The Dissociative Breakdown Of Negative Ions / By D. D. Clarke, Chemistry Department, Fordham University, New York, 10458, U.S.A. C. A. Coulson, Mathematical Institute, University Of Oxford, Donald Dudley Clarke Phd, C. A. Coulson Jan 1969

The Dissociative Breakdown Of Negative Ions / By D. D. Clarke, Chemistry Department, Fordham University, New York, 10458, U.S.A. C. A. Coulson, Mathematical Institute, University Of Oxford, Donald Dudley Clarke Phd, C. A. Coulson

Chemistry Faculty Publications

A discussion is given of the process whereby a substituted aromatic molecule captures a slow electron and dissociates. It is shown that the process often goes via two stages. and that the relative symmetries of the electroncapture state and the final dissociation state are very important. Both the sensitivity of the process to changes in the substituent and the existence of an activation energy are explained in the model


Actomyosin-Like Protein Isolated From Mammalian Brain / S. Puszkin, S. Berl, Columbia University, College Of Physicians And Surgeons, New York 10032, Elena Puszkin, Mount Sinai School Of Medicine, New York, D. D. Clarke, Fordham University, Bronx, New York, S. Puszkin, Soll Berl, Elena Puszkin, Donald Dudley Clarke Phd Jul 1968

Actomyosin-Like Protein Isolated From Mammalian Brain / S. Puszkin, S. Berl, Columbia University, College Of Physicians And Surgeons, New York 10032, Elena Puszkin, Mount Sinai School Of Medicine, New York, D. D. Clarke, Fordham University, Bronx, New York, S. Puszkin, Soll Berl, Elena Puszkin, Donald Dudley Clarke Phd

Chemistry Faculty Publications

A protein with characteristics similar to actomyosin has been isolated from whole brain of rat and cat. It is soluble in 0.6 molar potassium chloride and insoluble in 0.1 1nolar potassium chloride. It superprecipitates with magnesium ions and adenosine triphosphate. It has adenosine triphosphatase activity stimulated by either 1nagnesium or calcium ions. Both superprecipitation and adenosine triphosphatase activity are inhibited by p-chloromercuribenzoate and Mersalyl but not by ouabain


Compartmentation Of Glutamic Acid Metabolism In Brain Slices / S. Berl, W.J. Nicklas, And D.D. Clarke Department Of Neurology, College Of Physicians And Surgeons, Columbia University, Department Of Chemistry, Fordham University, New York, Soll Berl, William J. Nicklas, Donald Dudley Clarke Phd Jan 1968

Compartmentation Of Glutamic Acid Metabolism In Brain Slices / S. Berl, W.J. Nicklas, And D.D. Clarke Department Of Neurology, College Of Physicians And Surgeons, Columbia University, Department Of Chemistry, Fordham University, New York, Soll Berl, William J. Nicklas, Donald Dudley Clarke Phd

Chemistry Faculty Publications

(1) Compartmentation of glutamate metabolism in brain cortex previously observed only in vivo, has now been demonstrated in vitro. This was shown by using [U-14C]aspartate and [U-14C]glutamate as tracer substrates. (2) Preparation and maintenance of the slices at 0° resulted in reversible inhibition of glutamine synthesis. Preincubation at 37° for 10 min or preparation of the slices at room temperature partially overcame this inhibition. (3) Transfer to fresh medium after preincubation had an added stimulatory effect on glutamine synthesis. (4) Incubation in high K+ medium (27 mM) altered the relative specific activity of glutamine. (5) The data are ...


Effect Of Fluoroacetate On Amino Acid Metabolism / W. J. Nicklas, D. D. Clarke, And S. Berl. Chem. Dept., Fordham Univ., And Col. Of Physicians And Surgeons, Columbia Univ., New York, N. Y., William J. Nicklas, Donald Dudley Clarke Phd, Soll Berl Jan 1968

Effect Of Fluoroacetate On Amino Acid Metabolism / W. J. Nicklas, D. D. Clarke, And S. Berl. Chem. Dept., Fordham Univ., And Col. Of Physicians And Surgeons, Columbia Univ., New York, N. Y., William J. Nicklas, Donald Dudley Clarke Phd, Soll Berl

Chemistry Faculty Publications

Guinea pig brain cortex slices incubated in media containing U-14-aspartate or glutamate (GA) (J. Neurochem. in press) form glutamine ( GM) of relative specific activity (RSA)> 1 (GA=l). In the presence of 10-3 fluoroacetate (FA) the RSA of GM decreased to values considerably < 1 without any changes in levels of amjno acids; the % of label in GA doubled whilA that in GM decreased correspondingly. Similar results were obtained with 1-14 C-acetate as tracer in vivo (mice) and in vitro. RSA' s of Grvl > 1 have been explained by the compartmentation of GA in cerebral cortex. Consequently the effect of GA may be explained by an inhibition of the flow of metabolites through that pool of GA used preferentially for GM synthesis. This is consistent with the concept of the existence, in brain, of more than one citric acid cycle, one ...


A Micro Modification Of The Automatic Determination Of Serum Iron / Donald D. Clarke Nd Ruth Nicklas, Donald Dudley Clarke Phd, Ruth Nicklas Jan 1968

A Micro Modification Of The Automatic Determination Of Serum Iron / Donald D. Clarke Nd Ruth Nicklas, Donald Dudley Clarke Phd, Ruth Nicklas

Chemistry Faculty Publications

No abstract provided.