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1.
Public Health ; 126(5): 437-40, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22445716

RESUMO

OBJECTIVE: To investigate the long-term impact of health education in intestinal helminth infection control in rural Bangladesh. STUDY DESIGN: Longitudinal study to compare knowledge, awareness and practice for intestinal helminths between four communities: two receiving health education and two not receiving health education. METHODS: Parents of 1497 children aged between 2 and 8 years [781 (52.2%) received health education] were investigated by interview at baseline, endline (18 months) and follow-up (5 years). RESULTS: Health education had a significant effect on the installment of tubewells and latrines, but only had a temporary effect on health knowledge. CONCLUSION: This long-term follow-up study showed the lack of sustainability of knowledge and awareness in the long-term after health education interventions.


Assuntos
Educação em Saúde , Helmintíase/prevenção & controle , Enteropatias Parasitárias/prevenção & controle , Saneamento/normas , Abastecimento de Água/normas , Adulto , Bangladesh , Criança , Pré-Escolar , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Controle de Infecções , Masculino , Pais , População Rural
2.
Int J Immunopathol Pharmacol ; 23(2): 463-70, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20646341

RESUMO

Myoga (Zingiber Myoga Roscoe) is a perennial plant with a pungent smell from its flower buds. It is native to East Asia and has been reported to cause allergic contact dermatitis. The purpose of this study is to assess the allergenicity of myoga related to its major chemical components, alpha-pinene, beta-pinene, limonene, limonene oxide and beta-phellandrene, which are supposed to be the causative agents of contact dermatitis among myoga cultivators. We performed a toxicity study of the volatile constituents of myoga using the local lymph node assay (LLNA), in which limonene, limonene oxide and beta-phellandrene had positive responses and the EC3 was 35.8%, 8.22%, and 0.54%, respectively. EC3 for both alpha-pinene and beta-pinene was over 100%. Both chemicals failed to induce positive responses in the LLNA. While the maximization rating of limonene, limonene oxide and phellandrene were evaluated as moderate, extreme, and extreme respectively, alpha-pinene and beta-pinene were evaluated as weak in the previously reported GPMT. The usage of LLNA was also confirmed by comparing with previously reported GPMT results to detect the allergenicity of myoga constituents. The actual risk of humans developing an allergy to myoga constituents depends on many factors. The concentration of the compounds, the frequency and duration of exposure and the condition of the skin are supposed to be important factors.


Assuntos
Hipersensibilidade/etiologia , Ensaio Local de Linfonodo , Zingiberaceae/imunologia , Animais , Feminino , Cobaias , Camundongos , Camundongos Endogâmicos CBA
3.
Int J Immunopathol Pharmacol ; 20(2 Suppl 2): 31-4, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17903354

RESUMO

UNLABELLED: Mioga (Zingiber mioga Rosc.) is a member of the ginger family (Zingiberaceae), which is native to tropical Asia. In Japan, the young flower buds are used as a spice, and hand dermatitis suspected as being an allergy to mioga has been recognized in mioga greenhouse cultivators. To investigate the extent of the problems and the causes of dermatitis, 20 householders cultivating mioga in their greenhouses were asked to participate in a questionnaire study. Consecutive patch tests were performed on some subjects with dermatitis. Self-reported questionnaires were distributed to the main cultivator in each household who attended a lecture of mioga cultivation methods held at an agriculture cooperative association in the area. Some subjects who answered as presenting or having had hand dermatitis were patch tested for mioga (as is), four kinds of mioga extracts, and three kinds of natural rubber gloves. RESULTS: 35 cultivators from 16 households answered the questionnaire. Eight of the 35 subjects (22.9 percent) answered that they had experienced hand dermatitis since they started mioga cultivation. Four of the 8 subjects were patch tested. Two of the 4 subjects showed allergic reactions to mioga (as is) and the extracts. The other two cases showed irritation to mioga (as is). The first two cases also showed allergic reactions to natural rubber gloves. To our knowledge, there is no previous report of allergic contact dermatitis from mioga.


Assuntos
Doenças dos Trabalhadores Agrícolas/etiologia , Dermatite Alérgica de Contato/etiologia , Dermatite Ocupacional/etiologia , Zingiberaceae/efeitos adversos , Adulto , Doenças dos Trabalhadores Agrícolas/prevenção & controle , Dermatite Alérgica de Contato/prevenção & controle , Dermatite Ocupacional/prevenção & controle , Feminino , Luvas Protetoras , Mãos , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Testes do Emplastro , Inquéritos e Questionários , Zingiberaceae/imunologia
4.
Int J Immunopathol Pharmacol ; 20(2 Suppl 2): 23-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17903352

RESUMO

The purpose of this study is to investigate the safety of and to try to find the best plan to cope with exposure to FA for students during a gross anatomy dissection course. The FA exposure level and subjective symptoms was estimated. The relationship between exposure to FA and subjective symptoms of irritation were discussed for times; before, in the beginning period, in the middle period, and upon completion of the Anatomy Dissection Course. The geometric means of FA concentration were 32.7 micrograms/m3 (before), 891.3 micrograms/m3 (beginning), 763.3 micrograms/m3 (middle), and 238.9 micrograms/m3 (completion), respectively. Among them, FA-related symptoms were observed in 61.1 percent; 28.0 percent fell strong stress during the course, and 27.4 percent complained that their normal life situation was affected. Our results indicate that such subjective symptoms during the anatomy dissection course were related to the period spent in the anatomy dissection room. Our study suggests that shortening the time of each anatomy dissection practical class and reduction of the number of cadaver tables could help to reduce symptoms.


Assuntos
Fixadores/efeitos adversos , Formaldeído/efeitos adversos , Estudantes de Medicina , Adolescente , Adulto , Poluição do Ar em Ambientes Fechados/efeitos adversos , Poluição do Ar em Ambientes Fechados/análise , Anatomia/educação , Dissecação/efeitos adversos , Educação de Pós-Graduação em Medicina , Feminino , Fixadores/análise , Formaldeído/análise , Humanos , Japão , Masculino , Segurança , Inquéritos e Questionários
5.
Circ Res ; 86(2): 166-74, 2000 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-10666412

RESUMO

Transiently increased expression of leukocyte adhesion receptors after lung preservation contributes to early graft demise by recruiting leukocytes, activating complement, and causing microcirculatory stasis. We hypothesized that inhibiting intercellular adhesion molecule-1 (ICAM-1) expression even briefly may significantly improve lung graft function and that the preservation period might provide a unique window to deliver a therapeutic pulse of antisense oligonucleotide ICAM-1 to inhibit ICAM-1 expression after transplantation. Interleukin-1beta-treated rat pulmonary endothelial cells given a 20-mer phosphorothioate oligonucleotide comprising an antisense span targeted to the 3'-untranslated region of rat ICAM-1 demonstrated an oligonucleotide dose-dependent reduction in ICAM-1 expression. Using a cationic liposomal carrier, this same antisense oligonucleotide (but not the sense control) instilled into the pulmonary vasculature at the time of preservation reduced subsequent graft ICAM-1 expression and graft leukostasis and markedly improved oxygenation, pulmonary blood flow, and graft survival. These experiments demonstrate that the preservation period presents a window during which to target an anti-ICAM-1 expression strategy to inhibit early adhesion receptor expression and improve functional outcome after lung transplantation.


Assuntos
Sobrevivência de Enxerto , Molécula 1 de Adesão Intercelular/genética , Transplante de Pulmão , Oligonucleotídeos Antissenso/farmacologia , Preservação de Órgãos/métodos , Animais , Células Cultivadas , Endotélio Vascular/citologia , Expressão Gênica/genética , Expressão Gênica/fisiologia , Pulmão/citologia , Pulmão/enzimologia , Pulmão/imunologia , Masculino , Microcirculação , Neutrófilos/citologia , Peroxidase/análise , Circulação Pulmonar , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos Lew
6.
J Heart Lung Transplant ; 17(8): 835-45, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9730434

RESUMO

BACKGROUND: Rapid increase of pulmonary vascular resistance (PVR) early after reperfusion remains a major issue in clinical lung transplantation. A potent vasoconstrictor peptide, endothelin- plays an important role in various pulmonary pathophysiologic conditions and might induce increased PVR. We investigated the expression and influence of endothelin-1, and the effects of an ETA and ETB nonselective endothelin receptor antagonist, TAK-044, at reperfusion after cold preservation in a canine lung transplantation model. METHODS: Left single lung allotransplantation procedures were performed in three groups of animals. In group I (n=5) lungs were preserved for 12 hours; in group II (n=5) lungs were preserved for 18 hours; and in group III (n=6) lungs were also preserved for 18 hours, and TAK-044 (5 mg/kg) was administered just before reperfusion. All donor lungs were flushed and preserved with low-potassium dextran glucose solution at 4 degrees C. RESULTS: Six hours after reperfusion, arterial oxygen tension (mm Hg, inspired oxygen fraction=1.0) was 512.9+/-34.7 in group I, 152.4+/-46.7 in group II, and 509.6+/-29.0 in group III; PVR index (dyne x sec x cm(-5) x m2) was 1130+/-142 in group I, 1820+/-142 in group II, and 1287+/-191 in group III. Plasma endothelin-1 level was elevated significantly, and endothelin-1-like immunoreactivity was found in a variety of pulmonary vascular tissue and was seen less with immunohistochemical evaluation in group II in bronchial tissue. CONCLUSIONS: These results suggest that endothelin-1 is expressed as a result of ischemia-reperfusion injury and may worsen early graft function. TAK-044 is beneficial in protecting the graft from high pulmonary vascular resistance and pulmonary edema during the early posttransplantation stage.


Assuntos
Criopreservação , Endotelina-1/biossíntese , Transplante de Pulmão , Pulmão/efeitos dos fármacos , Peptídeos Cíclicos/farmacologia , Animais , Cães , Antagonistas dos Receptores de Endotelina , Pulmão/irrigação sanguínea , Pulmão/metabolismo , Circulação Pulmonar , Troca Gasosa Pulmonar , Traumatismo por Reperfusão/metabolismo , Resistência Vascular
8.
Nihon Kyobu Geka Gakkai Zasshi ; 45(12): 1931-42, 1997 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-9455104

RESUMO

Recently much interests have focused on the imbalance between the release of thromboxane A2 (TXA2) and prostaglandin I2 (PGI2), which may contribute to the development of pulmonary vascular injury. TXB2 has potents of platelet aggregation and vasoconstriction, while PGI2 has against in its activities. We investigated the effect of new PGI2 analogue (ONO-1301), which is a novel prostacyclin mimetic with inhibitory activity against thromboxane synthetase, on the early graft function in canine left single lung allotransplantation model. 19 donor dogs were divided into three groups. Seven dogs were comprised control group and received heparin administration (400 Unit/kg) before pulmonary arterial flushing with 50 ml/kg of 4 degrees C low potassium dextran glucose (LPDG) solution. Each six dogs were comprised I2-10 and I2-50 groups respectively, with receiving a 10-minute infusion of ONO-1301 (10 micrograms/kg/min) before flushing. The pulmonary cold preservation was performed with LPDG solution at 4 degrees C for 18 hours. After left single lung transplantation, in control group, saline solution was administered to the recipient for 10 minutes encompassing the reperfusion process (starting from 5 minutes prior to reperfusion). In I2-10 group, the ONO-1301 (10 micrograms/kg/min) was administered in the same manner. In I2-50 group, the ONO-1301 was administered from the same timing as I2-10 group, but for 50 minutes. The recipient dogs were observed for 6 hours after ligation of the right pulmonary artery and bronchus. We measured the transplanted lung function, including arterial blood gas and pulmonary hemodynamics, and plasma 6-keto-PGF1 alpha, TXB2 and lipid peroxide levels of left atrial blood. Pulmonary histological investigation was performed after preservation and sacrifice the recipient dog. All recipient dogs were survived for observation period. I2 groups provided significantly better gas exchange and pulmonary hemodynamics than control group. The 6-keto-PGF alpha levels in control group peaked after an early rise in TXB2 levels, and reached maximum at one hour after contra-lateral ligations. These prostanoid release levels rose again at 6 hours. While in I2 groups, the levels of them were significantly lower compared with control group. Histological examination of the transplanted lung after assessment, revealed disruption of alveoli forced by pulmonary edema in control group. In contrast, there was minimal fluid extravasation without alveolar disruption in both I2-10 and I2-50 groups. There were no significant differences between I2-10 and I2-50 groups. Although it dose not protect the implanted lung completely from developing edema, the ONO-1301 administration (10 micrograms/kg/min) to the donor and the recipient resulted in prevention of TXA2 and PGI2 release and improvement of the respiratory function and pulmonary hemodynamics after reperfusion. We conclude that it seems beneficial to administer the ONO-1301 to the donor and the recipient in order to regulate the prostanoid release and maintain the early graft function.


Assuntos
Inibidores Enzimáticos/farmacologia , Transplante de Pulmão , Prostaglandinas/metabolismo , Piridinas/farmacologia , 6-Cetoprostaglandina F1 alfa/sangue , Animais , Cães , Epoprostenol/análogos & derivados , Transplante de Pulmão/fisiologia , Reperfusão , Tromboxano A2/sangue
9.
Nucleic Acids Symp Ser ; (16): 65-8, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-4088885

RESUMO

With a view to examine the possibility of introducing an "up" amino residue into the sugar moiety of uracil nucleosides through 2,3'-N-cyclonucleosides, 2,3'-imino and 2,3'-substituted imino-1-(5'-O-benzoyl-beta-D-lyxofuranosyl)uracils, 2a4, 2b5 and 2c-f, were synthesized and debenzoylated correspondingly to 3a4, 3b5 and 3c-f. Hydrolysis of 3a,c,d,e with one to one mixture of 6N-NaOH and EtOH allowed the isolation of the corresponding 2,3'-N-bridged lyxopyranosyl nucleosides 4 in optically active, crystalline form. This is the first example of furanosyl to pyranosyl conversion in the field of pyrimidine cyclonucleosides.


Assuntos
Uracila/análogos & derivados , Fenômenos Químicos , Química , Isomerismo , Espectrofotometria Ultravioleta , Relação Estrutura-Atividade
10.
Nucleic Acids Symp Ser ; (27): 109-10, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1289781

RESUMO

The reaction of 1-(2,3-anhydro-5-O-trityl-beta-D-lyxofuranosyl)-2-O-methyluracil (1a) and its thymine analogue (1b) with dilithium tetrahalocuprate (Li2CuX4) revealed excellent to perfect regioselectivity, yielding 2,2'-anhydro-3'-halonucleosides (2a-d), while the same reactions with 2,3-anhydro uracil and thymine nucleosides (4a,b) gave arabinosyl (5a-d) and xylosyl halohydrins (6a-d) with the respective product ratio of 7:3 to 8:2. compounds 5 and 6 were isolated as the 2-O-(7) and 3- O-mesyl derivatives (8).


Assuntos
Brometos/química , Cloretos/química , Cobre/química , Nucleosídeos de Pirimidina/química , Estrutura Molecular
11.
Nucleic Acids Symp Ser ; (12): 17-20, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6664855

RESUMO

Synthesis of some 2,3'-aminimino and 2,3'-N alpha, N beta-dimethylhydrazo uracil cyclonucleosides are reported as part of our recent program to expand the range of the model conformations of cyclonucleosides. 1a with monoacetate of hydrazine or of methyl-hydrazine gave 2,3'-aminimino- (3a) or 2,3'-methylaminimino-1-(5'-O-benzoyl-beta-D-lyxofuranosyl) uracil (3b) in a fair yield. 1a with diluted free bases also gave 3a,b. These were converted into the deprotected forms (4a,b). On the other hand, reaction of 1a with monoacetate of N alpha, N beta-dimethylhydrazine gave 2,3'-N alpha, N beta-dimethylhydrazo-1-beta-D-lyxofuranosyluracil (6) and its 5'-O-benzoyl derivative (5). 6 is more conveniently obtainable from the deprotected 2,2'-anhydronucleoside 7.


Assuntos
Nucleosídeos de Pirimidina/síntese química , Uridina/análogos & derivados , Fenômenos Químicos , Química
12.
Nucleic Acids Symp Ser ; (37): 41-2, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9585989

RESUMO

Michael addition of cytosine, N4-dimethyl-aminomethylidene-cytosine, uracil and thymine to the nitroolefin (2) generated in situ from 1-(4,6-O-benzylidene-3-deoxy-3-nitro-beta-D-glucopyranosyl)-uracil (1) gave the corresponding 2-(N1-pyrimidinyl)-2,3-dideoxy-3-nitro-beta-D-glucopyranosides (3-6). Compound 3 was also obtainable from 4.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/química , Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Citosina/química , Nucleosídeos/síntese química , Timina/química , Uracila/química , Uridina/análogos & derivados , Citosina/análogos & derivados , Indicadores e Reagentes , Estrutura Molecular , Nucleosídeos/química , Uridina/síntese química , Uridina/química
13.
Nucleic Acids Symp Ser ; (21): 121-2, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2608457

RESUMO

In contrast with direct tosylation of 5'-O-benzoyl- (1d) or 5'-O-pivaloyl-1-beta-D-lyxofuranosyl-uracil (1e) with TsCl/pyridine, tosylation of the 2', 3'-O-dibutylstannylene derivatives (4d,e) of these compounds proved to give the 3'-O-tosyl derivatives 2d, e selectively. Coversion of 2d as a model to 1-(5'-O-benzoyl-3'-deoxy-beta-D-glycero-pentofuran-2'-ulosyl )uracil (5-beta) by base-induced [1,2]-hydride shift was examined under various reaction conditions, and the alpha/beta ratio of the product mixture (5-alpha, beta) determined by 1H NMR spectroscopy in each case. The BzOLi/DMF combination has proved to be most profitable for obtaining 5-beta.


Assuntos
Uridina/análogos & derivados , Estereoisomerismo , Uridina/síntese química
14.
J Biol Chem ; 275(28): 21468-76, 2000 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-10806208

RESUMO

Little is known about interactions between endogenous anti-inflammatory paradigms and microvascular thrombosis in lung ischemia/reperfusion (I/R) injury. Interleukin (IL)-10 suppresses macrophage activation and down-regulates proinflammatory cytokine production, but there are no available data to suggest a link between IL-10, thrombosis, and fibrinolysis in the setting of I/R. We hypothesized that hypoxia/ischemia triggers IL-10 production, to dampen proinflammatory cytokine and adhesion receptor cascades and to restore vascular patency by fibrinolytic potentiation. Studies were performed in a mouse lung I/R model. IL-10 mRNA levels in lung were increased 43-fold over base line by 1 h of ischemia/2 h of reperfusion, with a corresponding increase in plasma IL-10. Expression was prominently localized in bronchial epithelial cells and mononuclear phagocytes. To study the link between IL-10 and fibrinolysis in vivo, the induction of plasminogen activator inhibitor-1 (PAI-1) was evaluated. Northern analysis demonstrated exaggerated pulmonary PAI-1 expression in IL-10 (-/-) mice after I/R, with a corresponding increase in plasma PAI/tissue-type plasminogen activator activity. In vivo, IL-10 (-/-) mice showed poor postischemic lung function and survival after I/R compared with IL-10 (+/+) mice. Despite a decrease in infiltration of mononuclear phagocytes in I/R lungs of IL-10 (-/-) mice, an increased intravascular pulmonary fibrin deposition was observed by immunohistochemistry and Western blotting, along with increased IL-1 expression. Recombinant IL-10 given to IL-10 (-/-) mice normalized the PAI/tissue-type plasminogen activator ratio, reduced pulmonary vascular fibrin deposition, and rescued mice from lung injury. Since recombinant hirudin (direct thrombin inhibitor) also sufficed to rescue IL-10 (-/-) mice, these data suggest a preeminent role for microvascular thrombosis in I/R lung injury. Ischemia-driven IL-10 expression confers postischemic pulmonary protection by augmenting endogenous fibrinolytic mechanisms.


Assuntos
Fibrinólise/imunologia , Interleucina-10/farmacologia , Interleucina-10/fisiologia , Isquemia/imunologia , Pulmão/irrigação sanguínea , Traumatismo por Reperfusão/imunologia , Animais , Fibrina/metabolismo , Fibrinólise/efeitos dos fármacos , Inflamação , Molécula 1 de Adesão Intercelular/sangue , Interleucina-1/sangue , Interleucina-1/genética , Interleucina-10/deficiência , Interleucina-10/genética , Isquemia/sangue , Pulmão/imunologia , Pulmão/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Inibidor 1 de Ativador de Plasminogênio/genética , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/tratamento farmacológico , Ativador de Plasminogênio Tecidual/genética , Transcrição Gênica
15.
Nucleic Acids Symp Ser ; (17): 57-60, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3562276

RESUMO

The X-ray analysis of 8,5'-(N-carbamoyloxy)-2-dimethylamino- methylene-9-(2',3'-0-isopropylidene-beta-D-ribofuranosyl)guanine (2a) has disclosed that some bond angles are significantly larger or smaller than the corresponding angles of normal ribonucleosides. Abnormally longer or shorter bond lengths have also been found. The base-sugar torsion angle of 2a has proved to reside between the C1'-C2' and C1'-C3' lines, and quite near the latter line. Some new 8,5'-carbamoyloxy bridged adenosines were also synthesized as 2',3'-protected forms.


Assuntos
Carbamatos/síntese química , Nucleosídeos de Purina/síntese química , Indicadores e Reagentes , Modelos Moleculares , Conformação de Ácido Nucleico , Relação Estrutura-Atividade , Difração de Raios X
16.
Nucleic Acids Symp Ser ; (25): 55-6, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1668776

RESUMO

2,2'-Anhydro-1-(3'-deoxy-3'-iodo-5'-O-trityl-beta-D-arabinofuranosyl) thymine (2) was synthesized from 2',3'-didehydro-3'-deoxythymidine (DHT). Compound 2 was readily converted into the 2',3'-anhydrolyxofuranosyl derivatives 4-6. Treatment of 4a with some nucleophiles (N3-, OMe-, Cl-) gave the corresponding 3'-substituted arabinosyl nucleosides (7a,c,e) together with the minor xylosyl isomers (8a,c,d). 7a,c,e were deprotected to 7b,d,f, respectively.


Assuntos
Timidina/análogos & derivados , Didesoxinucleosídeos/química , Estrutura Molecular , Estavudina , Timidina/síntese química , Timidina/química
17.
Nucleic Acids Symp Ser ; (15): 53-6, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6522294

RESUMO

To achieve a systematic synthesis of purine 8,5'-imino and substituted imino cyclonucleosides, 2',3'-O-isopropylidene-purinenucleosides substituted with a methylamino (4a,b), benzyl-amino (4c,d,g and h) and allylamino group (4e,f,i and j) at the C8 were synthesized. With these substrates in hand, extensive 8,5'-cyclization reactions were carried out using diphenyl carbonate/Et3N (Method A), N,N'-carbonyldiimidazole (Method B) and the Mitsunobu reaction (Method C) to give 8,5'-substituted imino cyclonucleosides (5a,c,d,e,f and g). The yields of cyclization by Method C are generally higher than by the other two methods. 5a, b,c,d,e,f,g and h were deprotected to the corresponding mother compounds 8 through one or two steps. In guanosine series, a new cyclic system comprising an 8,5'-carbamate ester bridge (6a-c) has been introduced.


Assuntos
Nucleosídeos de Purina/síntese química , Cromatografia em Camada Fina , Iminas/síntese química , Indicadores e Reagentes , Espectrofotometria Ultravioleta , Relação Estrutura-Atividade
18.
J Biol Chem ; 251(3): 587-98, 1976 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-175056

RESUMO

Chemical syntheses of the four deoxyribodecanucleotides, d(T-C-G-A-A-G-T-C-G-A), d(C-G-T-C-A-T-C-G-A-C), d(T-G-A-C-G-G-C-A-G-A), and d(C-T-A-A-A-T-C-T-G-C) are described. These polynucleotides form, respectively, segments 7 to 10 in the plan adopted for the total synthesis of the DNA corresponding to the precursor for the Escherichia coli tyrosine tRNA. The syntheses used the principles of stepwise addition of protected mono- and oligonucleotides to the 3'-hydroxyl end of growing oligonucleotide chains. Detailed schemes used in the present syntheses are shown in Diagrams 1 to 4 in the text. The final products were subjected to extensive chromatography and were characterized as pure by chemical and enzymatic procedures.


Assuntos
DNA Bacteriano/biossíntese , Escherichia coli/metabolismo , Genes , Polidesoxirribonucleotídeos/síntese química , Sequência de Bases , Oligodesoxirribonucleotídeos/síntese química , Diester Fosfórico Hidrolases , Biossíntese de Proteínas , RNA de Transferência/biossíntese , Espectrofotometria Ultravioleta , Transcrição Gênica , Tirosina/biossíntese
19.
J Biol Chem ; 251(3): 667-75, 1976 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-175058

RESUMO

The DNA duplex corresponding to the entire length (126 nucleotides) of the precursor for an Escherichia coli tyrosine tRNA has been synthesized. Duplex [I] (Sekiya, T., Besmer, P., Takeya, T., and Khorana, H. G.(1976) J. Biol. Chem. 251, 634-641), corresponding to the nucleotide sequence 1-26, containing single-stranded ends and carrying one appropriately labeled 5'-phosphate group, was joined to duplex [II] (Loewen, P. C., Miller, R. C., Panet, A., Sekiya, T., and Khorana, H. G. (1976) J. Biol. Chem. 251, 642-650) (nucleotide sequence 23-66 or 23-60) was phosphorylated with [gamma-33P]ATP at the 5'-OH ends. Duplex [III] (Panet, A., Kleppe, R., Kleppe, K., and Khorana, H. G. (1976) J. Biol. Chem. 251, 651-657) (nucleotide sequence 57-94 (Fig. 2)) was also phosphorylated at 5'-ends with [gamma-33P]ATP and was joined to duplex [IV] (Caruthers, M. H., Kleppe, R., Kleppe, K., and Khorana, H. G. (1976) J. Biol. Chem. 251, 658-666) (nucleotide sequence 90-126) which carried a 33P-labeled phosphate group on nucleotide 90. The joined product, duplex [III + IV] (nucleotide sequence 57-126) was characterized. The latter duplex was joined to the duplex [I + II] to give the total duplex. The latter contains singlestranded ends (nucleotides 1 to 6 and 121 to 126) which can either be "filled in" to produce the completely base-paired duplex or may be used to add the promoter and terminator regions at the appropriate ends.


Assuntos
DNA Bacteriano/biossíntese , Escherichia coli/metabolismo , Genes , Polinucleotídeo Ligases/metabolismo , RNA de Transferência/biossíntese , Sequência de Bases , Sítios de Ligação , Cinética , Conformação de Ácido Nucleico , Monoéster Fosfórico Hidrolases , Polinucleotídeo 5'-Hidroxiquinase/metabolismo , Biossíntese de Proteínas , Transcrição Gênica , Tirosina/biossíntese
20.
J Biol Chem ; 251(3): 565-70, 1976 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-765327

RESUMO

With the ultimate objective of the total synthesis of a tRNA gene including its transcriptional signals, an Escherichia coli tyrosine suppressor tRNA gene was chosen. The arguments in favor of this choice are presented. A plan for the total synthesis of the 126-nucleotide-long DNA duplex corresponding to a precursor (Altman S., and Smith, J. D. (1971) Nature New Biol. 233, 35) to the above tRNA is formulated. The plan involves: (a) the chemical synthesis of 26 deoxyribooligonucleotide segments, (b) polynucleotide ligase-catalyzed joining of several segments at a time to form a total of four DNA duplexes with appropriate comlementary single-stranded ends, and (c) the joining of the duplexes to form the entire DNA duplex. Ten accompanying papers describe the experimental realization of this objective.


Assuntos
DNA Bacteriano/biossíntese , Escherichia coli/metabolismo , Genes , RNA de Transferência/biossíntese , Sequência de Bases , Conformação de Ácido Nucleico , Oligodesoxirribonucleotídeos/síntese química , Polidesoxirribonucleotídeos/síntese química , Polinucleotídeo Ligases/metabolismo , Biossíntese de Proteínas , Transcrição Gênica , Tirosina/metabolismo
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