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1.
Actas Urol Esp ; 30(3): 321-3, 2006 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-16749591

RESUMO

We report a case of encrusted prostatitis, term which is not found in MedLine search. Alkaline encrusted cystitis was described 70 years ago and few cases have been described since that time, most of them associated with Corynebacterium infection. In fact, we find these two entities very similar, except for the organ affected. Both present irritative urinary symptoms, alkaline urine and tisular necrosis below a calcification layer. Another entity described in 1993 is encrusted pyelitis, related to patients with immunodeficiency, particularly those with renal transplantation and also associated with ureolytic bacteria. The treatment of encrusted cystitis an pyelitis may include specific antibiotics, urinary acidification and endoscopic excision of the calcified lesions.


Assuntos
Prostatite/patologia , Idoso , Humanos , Masculino
2.
Actas urol. esp ; 30(3): 321-323, mar. 2006. ilus
Artigo em Es | IBECS | ID: ibc-046136

RESUMO

Presentamos un caso clínico de prostatitis incrustante, término que no se encuentra en la búsqueda hecha en MedLine. La cistitis alcalina incrustante se describió hace 70 años y son pocos los casos descritos desde entonces, la mayoría de ellos asociados a infección por Corynebacterium1 . De hecho, consideramos que estas dos entidades son muy similares, excepto en lo que se refiere al órgano afectado. Ambas presentan síntomas urinarios causantes de irritación, orina alcalina y necrosis tisular por debajo de una capa de calcificación. Otra entidad descrita en 1993 es la pielitis incrustante, relacionada con pacientes con inmunodeficiencia, especialmente los receptores de trasplante renal y también asociada a bacterias ureolíticas. El tratamiento de la cistitis y la pielitis incrustantes puede incluir antibióticos específicos, acidificación urinaria y escisión endoscópica de las lesiones calcificadas


We report a case of encrusted prostatitis, term which is not found in MedLine search. Alkaline encrusted cystitis was described 70 years ago and few cases have been described since that time, most of them associated with Corynebacterium infection1 In fact, we find these two entities very similar, except for the organ affected. Both present irritative urinary symptoms, alkaline urine and tisular necrosis below a calcification layer. Another entity described in 1993 is encrusted pyelitis, related to patients with immunodeficiency, particularly those with renal transplantation and also associated with ureolytic bacteria. The treatment of encrusted cystitis an pyelitis may include specific antibiotics, urinary acidification and endoscopic excision of the calcified lesions


Assuntos
Masculino , Idoso , Humanos , Prostatite/fisiopatologia , Cistite/fisiopatologia , Infecções por Corynebacterium/complicações , Corynebacterium/patogenicidade , Antibacterianos/uso terapêutico
3.
J Org Chem ; 66(10): 3495-501, 2001 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-11348135

RESUMO

The quaternizations of dibenzoquinolizines 9 and 14 with 3-halo-1-propanols are highly cis-selective (94-100% cis), results consistent with the N-methylation of O-methylcapaurine (7b), but in contrast to the proposed trans-stereochemistry of dibenzo[a,h]quinolizine methiodide 10 and the analogous quaternizations of 1-benzyl- and 1-phenylisoquinoline congeners 5b and 5c. In this report, we describe stereoselective preparation of the unique cis-dibenzoquinolizinium propanols 15 and 16and their transformation into bis- and mixed-onium chlorofumarates 19, 20ab, and 26. Dibenzo[a,g]quinolizinium propanol 15 was prepared enantioselectively in three steps from dihydroisoquinoline 11. Asymmetric transfer hydrogenation of 11 in the presence of triethylamine/formic acid and Noyori's chiral ruthenium catalyst 12 produced R-(-)-5',8-dimethoxynorlaudanosine (13) in 98% yield and 87% ee. Pictet-Spengler cyclization of 13 in formalin/formic acid afforded the dibenzo[a,g]quinolizine 14 in 65% yield. Quaternization of 14 with 3-chloro-1-propanol under Finkelstein conditions generated cis-dibenzoquinolizinium propanol 15 in 85% yield with >94% cis-selectivity. The cis-dibenzo[a,h]quinolizinium propanol 16 was obtained as a single stereoisomer by reaction of the known tetramethoxyquinolizine 9 with neat 3-iodo-1-propanol. Bis-onium chlorofumarates 18 and 19 and the mixed-onium derivative 20ab were prepared by a pool synthesis procedure from (1R)-trans-6a, 16, and chlorofumaryl chloride (17). Mixed-onium alpha-chlorofumarate 26 was synthesized from (1S)-trans-6d, 15 and (+/-)-trans-2,3-dichlorosuccinic anhydride (22), employing a recently disclosed chlorofumarate mixed-diester synthesis. The title compounds (19, 20ab, and 26) displayed curare-like effects of ultrashort duration in rhesus monkeys.


Assuntos
Fármacos Neuromusculares não Despolarizantes/síntese química , Animais , Fumaratos/síntese química , Fumaratos/farmacologia , Macaca mulatta , Fármacos Neuromusculares não Despolarizantes/farmacologia , Quinolizinas/síntese química , Quinolizinas/farmacologia , Estereoisomerismo , Fatores de Tempo
5.
J Biol Chem ; 274(11): 7039-42, 1999 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-10066759

RESUMO

The ribonucleoside triphosphate reductase (RTPR) from Lactobacillus leichmannii catalyzes the reduction of nucleoside 5'-triphosphates to 2'-deoxynucleoside 5'-triphosphates and uses coenzyme B12, adenosylcobalamin (AdoCbl), as a cofactor. Use of a mechanism-based inhibitor, 2'-deoxy-2'-methylenecytidine 5'-triphosphate, and isotopically labeled RTPR and AdoCbl in conjunction with EPR spectroscopy has allowed identification of the lower axial ligand of cob(II)alamin when bound to RTPR. In common with the AdoCbl-dependent enzymes catalyzing irreversible heteroatom migrations and in contrast to the enzymes catalyzing reversible carbon skeleton rearrangements, the dimethylbenzimidazole moiety of the cofactor is not displaced by a protein histidine upon binding to RTPR.


Assuntos
Benzimidazóis/metabolismo , Cobamidas/metabolismo , Lactobacillus/enzimologia , Ribonucleotídeo Redutases/metabolismo , Vitamina B 12/metabolismo , Catálise , Nucleotídeos de Desoxicitosina/farmacologia , Espectroscopia de Ressonância de Spin Eletrônica , Inibidores Enzimáticos/farmacologia , Ligantes , Ligação Proteica , Ribonucleotídeo Redutases/antagonistas & inibidores
7.
Org Lett ; 1(12): 1993-6, 1999 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-10836056

RESUMO

[formula: see text] The stereo- and regioselective synthesis of ultra-short-acting nondepolarizing neuromuscular blocker GW 0430 (5a) is described. Key steps involved the enantioselective transfer hydrogenation of imine 8 employing Noyori's catalyst, the stereoselective crystallization and methanolysis of trans-bataines 11 and 12, and the stereo- and regioselective trans elimination of hydrogen chloride from 14. The latter transformation allowed complete control of the position of the chloro substituent and stereochemistry at the double bond of the linker in 15.


Assuntos
Isoquinolinas/síntese química , Bloqueadores Neuromusculares/síntese química , Cristalização , Isoquinolinas/química , Metanol , Estereoisomerismo
8.
Biochemistry ; 37(18): 6419-26, 1998 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-9572859

RESUMO

Ribonucleotide reductases (RNRs) play a central role in replication and repair by catalyzing the conversion of nucleotides to deoxynucleotides. Gemcitabine 5'-diphosphate (F2CDP), the nucleoside of which was recently approved by the FDA for treatment of pancreatic cancer, is a potent mechanism-based inhibitor of class I and II RNRs. Inactivation of the Eschericia coli class I RNR is accompanied by loss of two fluorides and one cytosine. This RNR is composed of two homodimeric subunits: R1 and R2. R1 is the site of nucleotide reduction, and R2 contains the essential diferric-tyrosyl radical cofactor. The mechanism of inactivation depends on the availability of reductant. In the presence of reductant [thioredoxin (TR)/thioredoxin reductase (TRR)/NADPH or dithiothreitol], inhibition results from R1 inactivation. In the absence of reductant with prereduced R1 and R2, inhibition results from loss of the essential tyrosyl radical in R2. The same result is obtained with C754S/C759S-R1 in the presence of TR/TRR/NADPH. In both cases, tyrosyl radical loss is accompanied by formation of a new stable radical (0.15-0.25 equiv/RNR). EPR studies in 2H2O, with [U-2H]R1, and examination of the microwave power saturation of the observed signal, indicate by process of elimination that this new radical is nucleotide-based. In contrast to all previously investigated 2'-substituted nucleotide inhibitors of RNR, inactivation is not accompanied by formation of a new protein-associated chromophore under any conditions. The requirement for reductant in the R1 inactivation pathway, the lack of chromophore on the protein, the loss of two fluoride ions, and the stoichiometry of the inactivation all suggest a unique mechanism of RNR inactivation not previously observed with other 2'-substituted nucleotide inhibitors of RNR. This unique mode of inactivation is proposed to be responsible for its observed clinical efficacy.


Assuntos
Desoxicitidina/análogos & derivados , Inibidores Enzimáticos/farmacologia , Ribonucleotídeo Redutases/antagonistas & inibidores , Ribonucleotídeo Redutases/química , Cromatografia Líquida de Alta Pressão , Cistina Difosfato/análogos & derivados , Cistina Difosfato/farmacologia , Desoxicitidina/farmacologia , Ditiotreitol/farmacologia , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres , Espectrofotometria Ultravioleta , Gencitabina
9.
Biochemistry ; 37(16): 5528-35, 1998 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-9548936

RESUMO

Ribonucleoside triphosphate reductase (RTPR) from Lactobacillus leichmannii utilizes adenosylcobalamin and catalyzes the conversion of nucleoside triphosphates to deoxynucleoside triphosphates. One equivalent of 2',2'-difluoro-2'-deoxycytidine 5'-triphosphate, F2dCTP, rapidly inactivates RTPR. Analysis of the reaction products reveals that inactivation is accompanied by release of two fluoride ions and 0.84 equiv of 5'-deoxyadenosine and attachment of 1 equiv of corrin covalently to an active-site cysteine residue of RTPR. No cytosine release was detected. Proteolysis of corrin-labeled RTPR with endoproteinase Glu-C and peptide mapping at pH 5.8 revealed that C419 was predominantly modified. The kinetics of the inactivation have been examined by stopped-flow (SF) UV-vis spectroscopy and rapid freeze quench (RFQ) electron paramagnetic resonance (EPR) spectroscopy. Monitoring DeltaA525 nm shows that cob(II)alamin is formed with an apparent kobs of 50 s-1, only 2. 5-fold slower than a similar experiment carried out with cytidine 5'-triphosphate (CTP). The same reaction mixture was thus quenched at times from 22 ms to 30 s and examined by EPR spectroscopy. At early time points the EPR spectrum resembled a thiyl radical exchange coupled to cob(II)alamin. From 22 to 255 ms the total spin concentration remained unchanged at 1.4 spins/RTPR, twice that predicted by the amount of cob(II)alamin determined by SF. However, with time the signal attributed to the thiyl radical-cob(II)alamin disappears and new signal(s) with broad feature(s) at g = 2.33 and a sharp feature at g = 2.00 appeared, suggesting formation of cob(II)alamin and a nucleotide-based radical with only dipolar interactions. These studies have been interpreted to support the proposal that an RTPR-based thiyl radical can give rise to a nucleotide-based radical.


Assuntos
Desoxicitidina/análogos & derivados , Inibidores Enzimáticos/farmacologia , Lactobacillus/enzimologia , Ribonucleotídeo Redutases/antagonistas & inibidores , Compostos de Sulfidrila/farmacologia , Citosina/metabolismo , Desoxiadenosinas/metabolismo , Desoxicitidina/química , Desoxicitidina/metabolismo , Desoxicitidina/farmacologia , Espectroscopia de Ressonância de Spin Eletrônica , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Estabilidade Enzimática/efeitos dos fármacos , Fluoretos/metabolismo , Radicais Livres/metabolismo , Peptídeos/metabolismo , Desnaturação Proteica , Ribonucleotídeo Redutases/metabolismo , Espectrofotometria Ultravioleta , Vitamina B 12/metabolismo , Gencitabina
10.
Biochem Pharmacol ; 47(2): 365-71, 1994 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-8304981

RESUMO

The 2'-deoxy-2'-methylene derivatives of adenosine (MdAdo), guanosine (MdGuo), tubercidin (MdTu), cytidine (MdCyd) and uridine (MdUrd) were synthesized as mechanism-based inhibitors directed at ribonucleotide reductase. It was shown that MdCyd 5'-diphosphate irreversibly inactivated ribonucleotide reductase from Escherichia coli (Baker et al., J Med Chem 34: 1879-1884, 1991). In studies reported here, MdAdo/EHNA, MdGuo and MdCyd inhibited L1210 cell growth with IC50 values of 3.4, 10.6 and 1.4 microM, respectively. Since MdAdo is a substrate for adenosine deaminase, the presence of EHNA was required to give maximal growth inhibition. 8-Aminoguanosine was not required to maximize the cytotoxic effects of MdGuo. The 2'-deoxy-2'-methylene derivatives of tubercidin and uridine did not inhibit L1210 cell growth at concentrations as high as 50 microM (MdTu) or 100 microM (MdUrd). L1210 cell lines resistant to hydroxyurea (directed at the non-heme iron subunit of ribonucleotide reductase) or deoxyadenosine (directed at the effector binding subunit of ribonucleotide reductase) were not resistant to MdCyd. An L1210 cell line that was highly resistant to dGuo due to the loss of a relatively specific deoxyribonucleoside kinase (Cory et al., J Biol Chem 268: 405-409, 1993) had a 6.6-fold increase in the IC50 value toward MdCyd, but showed only a 2-fold increase in resistance to MdGuo. Another L1210 cell line that was markedly deficient in adenosine kinase activity was highly resistant to MdAdo. Analysis by flow cytometry showed that MdCyd showed the transit of the cells through the G2/M phase of the cell cycle resulting in the buildup of the G2/M population. MdAdo, MdGuo and MdCyd inhibited the incorporation of [14C]cytidine into DNA without an effect on RNA synthesis or total cellular uptake of [14C]cytidine. The conversion of [14C]cytidine to deoxycytidine nucleotides was partially inhibited by MdGuo, but not by MdAdo or MdCyd. These data show that the 2'-deoxy-2'-methylene derivatives of adenosine, guanosine and cytidine are activated via specific nucleoside kinases and that the modes of action of these compounds are not identical.


Assuntos
Desoxiadenosinas/farmacologia , Desoxicitidina/análogos & derivados , Desoxiguanosina/análogos & derivados , Desoxiuridina/análogos & derivados , Leucemia L1210/patologia , Tubercidina/análogos & derivados , Animais , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Desoxiguanosina/farmacologia , Leucemia L1210/enzimologia , Ribonucleotídeo Redutases/antagonistas & inibidores , Células Tumorais Cultivadas/efeitos dos fármacos
11.
J Med Chem ; 35(12): 2283-93, 1992 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-1613752

RESUMO

Treatment of 2-amino-6-chloro-9-(beta-D-ribofuranosyl)purine (21) with TBDMS chloride/imidazole/DMF gave a separable mixture of 5'-O, 2',5'-bis-O (22), 3',5'-bis-O (23), and 2',3',5'-tris-O-TBDMS derivatives. Oxidation of 22 and 23 with CrO3/pyridine/Ac2O, treatment of the respective ketonucleosides with methylenetriphenylphosphorane, and deprotection gave 2-amino-6-chloro-9-[3(and 2)-deoxy-3(and 2)-methylene- beta-D-erythro-pentofuranosyl]purines (28 and 37) that were converted into other 2-amino-6-substituted-purine analogues. Tubercidin was converted into 2'-deoxy-2'-methylenetubercidin (49) by an analogous route. Inactivation of S-adenosyl-L-homocysteine hydrolase by 2'- and 3'-methyleneadenosine analogues was investigated. Mechanism-based inhibition of S-adenosyl-L-homocysteine hydrolase and anticancer and antiviral activities of 2'(and 3')-deoxy-2'(and 3')-methylenenucleoside analogues are discussed.


Assuntos
Antineoplásicos/síntese química , Antivirais/síntese química , Hidrolases/antagonistas & inibidores , Nucleosídeos/síntese química , Ribonucleotídeo Redutases/antagonistas & inibidores , Adenosil-Homocisteinase , Animais , Antineoplásicos/farmacologia , Antivirais/farmacologia , Divisão Celular/efeitos dos fármacos , Desoxiadenosinas/síntese química , Desoxiadenosinas/farmacologia , Desoxicitidina/análogos & derivados , Desoxicitidina/síntese química , Desoxicitidina/farmacologia , Desoxiguanosina/análogos & derivados , Desoxiguanosina/síntese química , Desoxiguanosina/farmacologia , Humanos , Camundongos , Estrutura Molecular , Nucleosídeos/farmacologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Replicação Viral/efeitos dos fármacos
12.
J Med Chem ; 34(6): 1879-84, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2061926

RESUMO

It has been found that 2'-deoxy-2'-methyleneuridine (MdUrd), 2'-deoxy-2'-methylenecytidine (MdCyd), and 2'-deoxy-2',2'-difluorocytidine (dFdCyd) 5'-diphosphates (MdUDP (1) MdCDP (2) and dFdCDP (3), respectively) function as irreversible inactivators of the Escherichia coli ribonucleoside diphosphate reductase (RDPR). 2 is a much more potent inhibitor than its uridine analogue 1. It is proposed that 2 undergoes abstraction of H3' to give an allylic radical that captures a hydrogen atom and decomposes to an active alkylating furanone species. RDPR also accepts 3 as an alternative substrate analogue and presumably executes an initial abstraction of H3' to initiate formation of a suicide species. Both 2 and 3 give inactivation results that differ from those of previously studied inhibitors. The potent anticancer activities of MdCyd and dFdCyd indicate a significant chemotherapeutic potential. The analogous RDPR of mammalian cells should be regarded as a likely target and/or activating enzyme for these novel mechanism-based inactivators.


Assuntos
Desoxicitidina/análogos & derivados , Nucleotídeos de Desoxicitosina/farmacologia , Ribonucleotídeo Redutases/antagonistas & inibidores , Citosina/metabolismo , Desoxicitidina/farmacologia , Ditiotreitol/farmacologia , Escherichia coli/enzimologia , Espectrofotometria Ultravioleta
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