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1.
Gene Ther ; 21(4): 427-33, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24572788

RESUMO

As both the immune system and the blood-brain barrier (BBB) are likely to be developmentally immature in the perinatal period, neonatal gene transfer may be useful for the treatment of lysosomal storage disease (LSD) with neurological involvements such as metachromatic leukodystrophy (MLD). In this experiment, we examined the feasibility of single-strand adeno-associated viral serotype-9 (ssAAV9)-mediated systemic neonatal gene therapy of MLD mice. ssAAV9 vector expressing human arylsulfatase A (ASA) and green fluorescent protein (GFP) (ssAAV9/ASA) was injected into the jugular vein of newborn MLD mice. High levels of ASA expression were observed in the muscle and heart for at least 15 months. ASA was continuously secreted into plasma without development of antibodies against ASA. Global gene transfer into the brain and spinal cord (SC), across the BBB, and long-term ASA expression in the central nervous system were detected in treated mice. Significant inhibition of the accumulation of sulfatide (Sulf) in the brain and cervical SC was confirmed by Alcian blue staining and biochemical analysis of the Sulf content. In a behavior test, treated mice showed a greater ability to traverse narrow balance beams than untreated mice. These data clearly demonstrate that MLD mice model can be effectively treated through neonatal systemic injection of ssAAV9/ASA.


Assuntos
Dependovirus/genética , Terapia Genética , Leucodistrofia Metacromática/genética , Leucodistrofia Metacromática/terapia , Animais , Barreira Hematoencefálica , Cerebrosídeo Sulfatase/genética , Cerebrosídeo Sulfatase/uso terapêutico , Modelos Animais de Doenças , Vetores Genéticos , Proteínas de Fluorescência Verde/genética , Humanos , Leucodistrofia Metacromática/patologia , Camundongos
2.
Ecol Appl ; 21(7): 2349-56, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22073627

RESUMO

Tropical soils are particularly vulnerable to fertility losses due to their low capacity to retain organic matter and mineral nutrients. This urges the development of new agricultural practices to manage mineral nutrients and organic matter in a more sustainable way while relying less on fertilizer inputs. Two methods pertaining to ecological engineering and agroecology have been tested with some success: (1) the addition of biochar to the soil, and (2) the maintenance of higher earthworm densities. However, modern crop varieties have been selected to be adapted to agricultural practices and to the soil conditions they lead to and common cultivars might not be adapted to new practices. Using rice as a model plant, we compared the responsiveness to biochar and earthworms of five rice cultivars with contrasted selection histories. These cultivars had contrasted responsivenesses to earthworms, biochar, and the combination of both. The mean relative increase in grain biomass, among all treatments and cultivars, was 94% and 32%, respectively, with and without fertilization. Choosing the best combination of cultivar and treatment led to a more than fourfold increase in this mean benefit (a 437% and a 353% relative increase in grain biomass, respectively, with and without fertilization). Besides, the more rustic cultivar, a local landrace adapted to diverse and difficult conditions, responded the best to earthworms in terms of total biomass, while a modern common cultivar responded the best in term of grain biomass. This suggests that cultivars could be selected to amplify the benefit of biochar- and earthworm-based practices. Overall, selecting new cultivars interacting more closely with soil organisms and soil heterogeneity could increase agriculture sustainability, fostering the positive feedback loop between soils and plants that has evolved in natural ecosystems.


Assuntos
Adaptação Fisiológica/genética , Oryza/genética , Oryza/fisiologia , Solo/química , Clima Tropical , Animais , Biomassa , Carvão Vegetal , Fertilizantes , Oligoquetos/fisiologia
3.
Anal Sci ; 17(6): 709-13, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11707940

RESUMO

A new analytical method employing liquid chromatography/tandem mass spectrometry (LC/MS/MS) with a column-switching system was developed for quantitative determination of leukotriene E4 (LTE4) in human urine. A column-switching system using a trapping column, which concentrates the analyte and removes salts and other water-soluble contaminants, allowed direct injection of human urine. Because simultaneously eluted endogenous contaminants suppressed the ionization efficiency of LTE4, good liquid chromatographic separation was very important for establishing this method, notwithstanding the high selectivity of MS/MS. The calibration curve was linear over the range from 10 to 3000 pg/mL, and the method showed good accuracy and precision. This method should therefore be very useful for determination of LTE4 amounts in human urine in studies on leukotriene metabolism and the efficacy of antileukotriene drugs.


Assuntos
Cromatografia Líquida/métodos , Leucotrieno E4/urina , Espectrometria de Massas por Ionização por Electrospray/métodos , Cromatografia Líquida/instrumentação , Cromatografia Líquida/estatística & dados numéricos , Humanos , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Espectrometria de Massas por Ionização por Electrospray/estatística & dados numéricos
4.
Carbohydr Res ; 334(3): 233-41, 2001 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-11513830

RESUMO

FTIR spectra were obtained for several different states of trehalose including dihydrate crystal, anhydrous form II (designated by Gil, A. M.; Belton, P. S.; Felix V. Spectrochim. Acta 1996, A52, 1649-1659), anhydrate crystal, dried melt, amorphous solid and aqueous solution. From the observation of the symmetric and antisymmetric stretch vibrations of the glycosidic linkage, it is found that this sugar assumes at least three types of backbone conformations. Among them, the conformation with C(2) symmetry is characterized as 'open state', which means that the sugar easily absorbs water molecules. The conformation of the sugars in anhydrous form II and in freeze-dried trehalose is shown to be in the open state. Next, the hygroscopic properties of the anhydrate, form II and the amorphous solid are compared based on their IR spectra. Interestingly, form II alone is converted to the original dihydrate in a week under mild environmental-like conditions: relative humidity of 40% and room temperature. These results suggest the possibility that form II plays a role in avoiding the devitrification of the sugar glass. Finally, we discuss the role of form II in preserving freeze-dried biomaterials.


Assuntos
Trealose/química , Água/química , Animais , Cristalização , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Anal Sci ; 17(10): 1155-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11990587

RESUMO

We evaluated a new restricted access media (RAM) precolumn for direct analysis of drugs in plasma using a column switching HPLC system. The new RAM material was prepared by the modification of the external surface of porous silica with hydrophilic methylcellulose (MC), followed by modification of the internal surface with octadecylsilane (ODS). The external surface of the MC-immobilized ODS silica material (MC-ODS) suppressed the adsorption of proteins, while the internal surface of MC-ODS retained various types of drugs, such as ketoprofen, propranolol, caffeine and atenolol in plasma samples. In addition, MC-ODS allowed direct analysis of drugs in a 1000-microL plasma sample to monitor trace amounts of analytes contained. Reduced efficiency and clogging of the MC-ODS precolumn and/or the analytical column were not observed even after the repetitive injection of plasma sample up to 40 mL. Our results indicated that the MC-ODS precolumn could be used in pharmacodynamic and clinical studies.


Assuntos
Metilcelulose/química , Preparações Farmacêuticas/sangue , Animais , Atenolol/sangue , Cafeína/sangue , Cromatografia em Gel/métodos , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Cetoprofeno/sangue , Masculino , Propranolol/sangue , Proteínas/metabolismo , Ratos , Dióxido de Silício/química , Fatores de Tempo
8.
Biomacromolecules ; 2(4): 1315-23, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11777409

RESUMO

The comonomer compositional distribution and thermal and morphological characteristics were investigated for five bacterially synthesized poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] samples with 3HV content of 45, 49, 70, 80, and 96 mol %. All these samples were fractionated into many fractions with widely different 3HV content by changing solvent/nonsolvent volume ratio of chloroform/n-heptane mixtures. Bacterial P(3HB-co-3HV) samples investigated in this study were found to have broad comonomer compositional distribution. The tendencies of the fractional precipitation of the P((3HB-co-3HV)s with 3HV content lower than 60 mol % and those with 3HV higher than 80 mol % were found to be contrary. The 3HV content dependences of the thermal properties and crystalline structures were investigated for bacterial poly(3-hydroxybutyrate) [P(3HB)] and a series of compositionally well-fractionated P(3HB-co-3HV) samples with 3HV content ranged from 14 to 98 mol % by DSC, WAXD, and solid-state (13)C NMR. It was found that P(3HB-co-3HV) samples with 3HV content lower than about 47 mol % form the crystalline lattice having the P(3HB) homopolymer type lattice including the 3HV unit as the crystal constituent, and those with a 3HV content higher than about 52 mol % form the crystalline lattice having the P(3HV) homopolymer type lattice including the 3HB units. Thus, P(3HB-co-3HV)s show the crystalline structural change in a very narrow range of 3HV content.


Assuntos
Cupriavidus necator/metabolismo , Poliésteres/análise , Biodegradação Ambiental , Varredura Diferencial de Calorimetria , Fracionamento Químico , Cristalização , Fermentação , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Poliésteres/química , Poliésteres/isolamento & purificação , Difração de Raios X
9.
Anal Biochem ; 287(1): 45-54, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11078582

RESUMO

Surfactants suppress the electrospray ionization (ESI) of various compounds. Here we demonstrate that fluorinated surfactants such as perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOSA) could be employed for ESI-MS without a significant decrease in sensitivity. Both PFOA and PFOSA could be applied to the analysis of ionic and nonionic compounds by micellar electrokinetic chromatography (MEKC)/ESI-MS, although the migration window was limited. Furthermore, in HPLC/ESI-MS, PFOA could function as a paired ion for enzymatically digested peptides as well as sulfonamides and significant effects of PFOA on the signal peak shape, retention times, and sensitivity of the analytes were observed compared to those of trifluoroacetic acid or sodium dodecyl sulfate (SDS). In addition, PFOA was applied to protein analysis by ESI-MS, and superior sensitivity was noted, compared to other surfactants such as octylglucoside, dodecylglucoside, and SDS. Although 21% of the original signal was observed in the presence of 1% PFOA, this surfactant could be easily removed by evaporation, which resulted in the recovery of 96% of the original signal. Because these fluorinated surfactants could also be used for solubilization, extraction, and disaggregation of proteins, they should greatly expand the applicability of the ESI-MS to the biological problems of proteins.


Assuntos
Ácidos Alcanossulfônicos/química , Caprilatos/química , Fluorocarbonos/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Tensoativos/química , Antagonistas Adrenérgicos beta/química , Cafeína/química , Cromatografia Líquida de Alta Pressão , Detergentes/química , Micelas , Mioglobina/química , Peptídeos/análise , Conformação Proteica , Sensibilidade e Especificidade , Dodecilsulfato de Sódio/química , Ácido Trifluoracético/química
10.
Rapid Commun Mass Spectrom ; 14(14): 1167-78, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10918364

RESUMO

A novel method for electrophoretic mobility-assisted identifications of proteins, using capillary electrophoresis/mass spectrometry (CE/MS) under methanolic conditions, was developed. The number of functional groups of the enzymatic digest peptides was estimated from a single run CE/MS analysis and utilized as an additional tag for database searching in addition to the mass map of the peptides. The additional amino acid information thus obtained can improve the confidence level of the protein identification. The database searching software algorithm ProFound was modified to accept the tag, based on this new concept. In this study, optimization of the CE/MS conditions for the estimation of basic functional groups was performed as an example. An accurate value of the number of such functional groups was obtained from CE characteristics when methanolic buffer (methanol/formic acid/water = 60:20:20) was used, via an excellent correlation (r = 0.997) between the number of functional groups of the peptides and [MW((2/3))]. The mass spectrometry sensitivity was also improved when using the methanolic buffer in comparison with that obtained using aqueous 1% formic acid buffer. The identification of a protein of Saccharomyces cerevisiae, which was separated by two-dimensional electrophoresis, was performed using the methanolic buffer in combination with sheathless nanoelectrospray CE/MS. A protein spot that had not been identified by MALDI-TOFMS and LC/MS/MS was successfully identified using this new method.


Assuntos
Proteínas/análise , Proteínas/química , Sequência de Aminoácidos , Animais , Eletroforese Capilar/métodos , Humanos , Espectrometria de Massas/métodos , Dados de Sequência Molecular
11.
J Chromatogr A ; 875(1-2): 315-22, 2000 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-10839151

RESUMO

Perfect control of electroosmotic flow (EOF) was achieved by dovetailing successive multiple ionic-polymer layer (SMIL) coated capillaries. The direction and magnitude of the EOF was perfectly controllable over the pH range 2-13. Zone diffusion was not observed, even if the inner wall of the dovetailed capillary was discontinuous, or if the sample zone passed through the connected part of the capillary because the RSDs of migration time, theoretical plates, symmetry factor and S/N of the marker were almost the same when seamless capillary and dovetailed capillary were compared. The dovetailed capillary was applied to cyclodextrin modified capillary zone electrophoresis. The control of the EOF enabled us to control both the resolution and the migration order of the enantiomers. The migration time was also controllable and, therefore, the best condition between separation and migration time could be determined by controlling the EOF. Partial filling affinity electrokinetic chromatography with a protein used as a chiral selector was also studied. The migration of the pseudostationary phase was controllable by EOF, and detection of the solute at 214 nm was possible. Therefore, the EOF-controlled dovetailed capillary has great potential to expand the application of the separation technique.


Assuntos
Eletroforese Capilar/métodos , Osmose , Estereoisomerismo
12.
J Pharm Sci ; 88(12): 1305-12, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10585227

RESUMO

Lipophilicity scales were characterized by an approach using vectors provided from solvation energy descriptors (SED) of solutes such as an excess molar refraction, the dipolarity/polarizability, the hydrogen-bond acidity, the basicity, and the McGowan characteristic volume. The five components of the SED vector were obtained from the coefficients of the five SED terms of the linear solvation energy relationship (LSER) equation for the lipophilicity scales. The analogy between two lipophilicity scales was expressed as the angle between the two SED vectors, while the difference in the contribution of the five independent SEDs to these two lipophilicity scales was quantified by the difference of the unit vectors of the SED vectors. These approaches were applied to several lipophilicity scales measured using microemulsions, micelles, an immobilized artificial membrane column, and an octanol-water system. As a result, the quantitative classification of these scales was successfully carried out, and the difference in the scales was well characterized. In addition, this vector approach was extended to the estimation of the contribution of each constituent of the microemulsions to the lipophilicity scale. Furthermore, some biological parameters such as skin permeability and the distribution between blood and brain could be predicted by the summation of the SED vectors obtained from the chromatographic systems. These results suggest that complex biological systems can be expressed quantitatively by simple chemical models with their SED vectors.


Assuntos
Físico-Química/normas , Lipídeos/química , Algoritmos , Barreira Hematoencefálica , Emulsões , Transferência de Energia , Micelas , Modelos Biológicos , Absorção Cutânea , Solubilidade , Espectrofotometria Ultravioleta
13.
Cryobiology ; 39(1): 80-7, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10458903

RESUMO

It is well known that yeast cells survive environmental stresses such as desiccation and freezing and there is evidence that these phenomena may be related to the presence of trehalose in the cells. However, the molecular mechanism by which trehalose might exert an influence on cell functions remains unknown. In this report, thermogravimetry and differential thermal analysis were used to estimate the amount of bound water in yeast cells. It is shown that when the trehalose content is greater than 2-3% of the cell dry weight, the amount of bound water is drastically decreased and the viability of the dried cells is increased. This implies that a major portion of the bound water is replaced by trehalose. In addition, measurements of the NMR spin-lattice relaxation time of the intracellular water protons show that trehalose acts as a water-structuring agent in hydrated yeast cells. This dual role is essential for high resistance to water stress in yeast cells.


Assuntos
Saccharomyces cerevisiae/metabolismo , Trealose/metabolismo , Água/metabolismo , Líquido Intracelular/metabolismo , Espectroscopia de Ressonância Magnética , Pressão Osmótica , Preservação Biológica , Temperatura
14.
Anal Biochem ; 266(1): 125-32, 1999 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-9887221

RESUMO

The cholyl-adenylate, covalently bound 3alpha, 7alpha, 12alpha-trihydroxy-5beta-cholanoic acid (cholic acid) with adenosine 5'-monophosphate having an acid anhydride linkage, has been characterized by means of liquid chromatography/mass spectrometry in an incubation mixture with a rat liver microsomal fraction. The authentic specimen of cholyl-adenylate was synthesized using the carbodiimide method and the structure was confirmed by MS and nuclear magnetic resonance spectroscopy. After incubation of cholic acid with a hepatic microsomal fraction in the presence of adenosine 5'-triphosphate, bile acids were extracted and purified by solid-phase extraction on a Sep-Pak C18 cartridge and then subjected to a LC/MS analysis, where cholyl-adenylate and a CoA thioester of cholic acid (cholyl-CoA) were monitored with characteristic negative ions of m/z 736 and 577, respectively. Cholyl-adenylate was definitely characterized and preferential biotransformation into the acyl-adenylate prior to formation of cholyl-CoA was noted. The nonenzymatic formation of taurine-conjugated cholic acid by incubation of cholyl-adenylate with taurine in a buffer solution was also demonstrated.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Ácidos Cólicos/análise , Ácidos Cólicos/química , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Microssomos Hepáticos/química , Acil Coenzima A/síntese química , Acil Coenzima A/metabolismo , Monofosfato de Adenosina/análise , Monofosfato de Adenosina/síntese química , Monofosfato de Adenosina/química , Trifosfato de Adenosina/química , Animais , Ácido Cólico/química , Ácidos Cólicos/síntese química , Ácidos Cólicos/metabolismo , Masculino , Microssomos Hepáticos/metabolismo , Ratos , Ratos Wistar , Taurina/química , Ácido Taurocólico/química
15.
Anal Chem ; 70(24): 5272-7, 1998 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-9868917

RESUMO

A coated capillary modified with a cationic polymer was developed by using a novel coating procedure, successive multiple ionic-polymer (SMIL) coating. The SMIL coating was achieved by first attaching the cationic polymer to the capillary inner wall, and then the anionic polymer to the cationic polymer layer, and finally the cationic polymer to the anionic polymer layer. The stability of Polybrene (PB)-modified capillary made by SMIL coating was remarkably improved in comparison with a conventional PB-modified capillary. It endured during 600 replicate analyses and also showed strong stability against 1 M NaOH and 0.1 M HCl. The relative standard deviation of the run-to-run, day-to-day, and capillary-to-capillary coating was all below 1%, and good reproducibilities were obtained. The PB-modified capillary made by SMIL coating was applied to the basic protein analyses. It gave good performances for the protein analyses even when the pH of the electrolyte was near the isoelectric point (pI) of the protein. In addition, 0.1 M NaOH rinse prior to the sample injection allowed the reproducible analysis of a highly adsorptive sample such as plasma because the adsorbed sample could be flushed out of the capillary. Besides protein analyses, an efficient analysis of the cationic drugs by capillary electrophoresis/mass spectrometry (CE/MS) was also possible.


Assuntos
Eletroforese Capilar/métodos , Brometo de Hexadimetrina , Cátions , Proteínas/análise , Reprodutibilidade dos Testes
16.
Biosci Biotechnol Biochem ; 62(6): 1211-5, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9692206

RESUMO

The structure of the N-linked carbohydrate chains of peptide isomerase from the venom of the funnel web spider (Agelenopsis aperta) has been analyzed. Carbohydrates were released from peptide isomerase by hydrazinolysis and reductively aminated with 2-aminopyridine. The fluorescent derivatives were purified by phenol/chloroform extraction, followed by size-exclusion HPLC. The structure of the purified pyridylamino (PA-) carbohydrate chains were analyzed by a combination of two-dimensional HPLC mapping, sugar composition analysis, sequential exoglycosidase digestions, and mass spectrometry. The peptide isomerase contains six kinds of N-linked carbohydrate chains of truncated high-mannose type, with a fucose alpha 1-6 linked to the reducing N-acetylglucosamine in approximately 80% of them.


Assuntos
Isomerases de Aminoácido/química , Poliaminas/análise , Venenos de Aranha/análise , Aminopiridinas , Configuração de Carboidratos , Sequência de Carboidratos , Cromatografia Líquida de Alta Pressão , Dados de Sequência Molecular
17.
Anal Chem ; 70(11): 2254-60, 1998 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-9624899

RESUMO

A stable modification of the inner wall of a fused silica capillary was established by a simple coating procedure, successive multiple ionic-polymer layer (SMIL) coating. An anionic polymer was tightly fixed to the capillary wall by the SMIL coating, in which a cationic polymer was sandwiched between the anionic polymer and the uncoated fused silica capillary by noncovalent bonding. The SMIL-coated capillary showed a long lifetime. The endurance of the SMIL-coated capillary was more than 100 runs, and it was also tolerant to organic solvents, 1 M NaOH, and a surfactant. The coating efficiency did not depend on capillary sources, and the relative standard deviation of capillary-to-capillary reproducibility was less than 1%. In this study, dextran sulfate (DS) was used as the anionic polymer, and Polybrene was used as the cationic polymer for SMIL modification. The DS-modified capillary (SMIL-DS capillary) exhibited a pH-independent electroosmotic flow (EOF) from anode to cathode in the pH range of 2-11. The SMIL-DS capillary showed good performance for acidic protein analyses under physiological conditions (pH 7.4). Also, the presence of EOF under acidic conditions permitted new applications. Simultaneous separations of cationic, anionic, and neutral amino acids were achieved by capillary zone electrophoresis, and separations of cresol isomers were achieved by micellar electrokinetic chromatography under the acidic conditions. The SMIL-DS capillary was also useful for fast and precise determination of the pKa of acidic functional groups.


Assuntos
Eletroforese Capilar/métodos , Aminoácidos/análise , Ânions , Sulfato de Dextrana/química , Eletroforese Capilar/instrumentação , Brometo de Hexadimetrina/química , Concentração de Íons de Hidrogênio , Micelas , Proteínas/análise , Dióxido de Silício/química , Hidróxido de Sódio , Solventes , Tensoativos
18.
Microbiol Immunol ; 42(11): 761-71, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9886149

RESUMO

We investigated the relationship between the two forms of rabies virus P protein, a non-catalytic subunit of rabies virus RNA polymerase. The two displayed different electrophoretic mobilities as 37- and 40-kDa polypeptides, hence termed as p37 and p40, respectively. Double labeling experiments with [3H]leucine and [32P]orthophosphate demonstrated that p40 was much more phosphorylated than p37. Treatment of the virion proteins with alkaline phosphatase eliminated only p40, and not 37-kDa polypeptide. The p37 was a major product of the P gene, and was accumulated in the infected cell and incorporated into the virion. On the other hand, p40 was apparently detected only in the virion, and little detected in the cells. Treatment of infected cells with okadaic acid, however, resulted in significant accumulation of p40 in the cell, suggesting that p40 was continuously produced in the cell but dephosphorylated quickly. We detected both 37- and 40-kDa products in P cDNA-transfected animal cells, while only a 37-kDa product was produced in Escherichia coli. Incubation of 37-kDa products from E. coli with the lysates of animal cells in vitro resulted in the production of a 40-kDa product, which was also shown to be suppressed by the heparin. From these results, it is suggested that p40 is produced by the hyperphosphorylation of a 37-kDa polypeptide, which depends on certain heparin-sensitive cellular enzyme(s) and occurs even in the absence of the other viral gene products, and that p40 is reverted quickly to p37 in the infected cells, probably being dependent on some virus-induced factor(s).


Assuntos
RNA Polimerases Dirigidas por DNA/química , Vírus da Raiva/enzimologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/biossíntese , Sequência de Bases , Células Cultivadas , Cricetinae , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/imunologia , Immunoblotting , Dados de Sequência Molecular , Peso Molecular , Fosforilação , Coelhos
19.
Biol Pharm Bull ; 20(4): 455-9, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9145231

RESUMO

The release behavior of phosphorothioate oligodeoxynucleotide, 5'-GCCGAGGTCCATGTCGTACGC-3' (ODN), from poly(lactic acid-co-glycolic acid) (PLGA) implant was studied. The pillar shape implant was fabricated by the heating mold method. About 20% of ODN were released initially, and the subsequent pseudo-zero-order release lasted for more than 20 d from a PLGA10000 implant loaded with 8.4% ODN in phosphate buffered saline, pH 7.4. The duration of ODN release did not depend on the molecular weights of PLGA, and pseudo-zero-order release may be achieved by changing the loaded amount of ODN in fabrication of the PLGA implant. Almost the same release profiles were obtained in the pH range of 7.2 to 7.6, which is known as the physiological pH of a vitreous body. Furthermore, the duration of intact ODN release in bovine vitreous was found. The implant in the present study may possibly be applicable to intravitreal implantation for the treatment of ocular disease.


Assuntos
Materiais Biocompatíveis/química , Ácido Láctico , Oligonucleotídeos/química , Ácido Poliglicólico , Polímeros/química , Tionucleotídeos/química , Animais , Bovinos , Implantes de Medicamento , Peso Molecular , Oligonucleotídeos/análise , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Próteses e Implantes , Tionucleotídeos/análise , Corpo Vítreo/química
20.
Anal Biochem ; 244(2): 291-300, 1997 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9025946

RESUMO

Sphingolipid metabolites ceramide, sphingomyelin, sphingosine, psycosine, sphingosylphosphorylcholine, and dimethylsphingosine were separated and simulataneously quantitated by liquid chromatography/ionspray ionization tandem mass spectrometry (LC/MS/ MS). The use of glassware throughout minimized losses due to adsorption and the pretreatment of this method consisted of simple liquid-liquid extraction procedure with a mixture of chloroform and methanol. After separation on a short C18 silica column eluted in a gradient mode, the metabolites were detected by MS/ MS. This assay allows simultaneously quantification of these metabolites over a range of at least 0.1 to 100 ng/ 10(6) cells. The LC/MS/MS analyses took 10 to 15 min per sample and we could examine up to 50 samples per day. We also detected endogenous sphingosine 1-phosphate in HL-60 cells. The utility of the method was demonstrated by examining changes in metabolites levels in HL-60 cells after treatment with sphingomyelinase. It was found that sphingomyelinase from Bacillus cereus may have selectivity for acyl chain length.


Assuntos
Cromatografia Líquida/métodos , Lisofosfolipídeos , Espectrometria de Massas/métodos , Esfingolipídeos/análise , Ceramidas/análise , Cromatografia Líquida de Alta Pressão , Células HL-60 , Humanos , Esfingomielina Fosfodiesterase/metabolismo , Esfingosina/análogos & derivados , Esfingosina/análise
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