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1.
J Infect Chemother ; 23(10): 692-697, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28807755

RESUMO

We hypothesized that cases of uncomplicated cystitis treated in a Urology Department would display higher antimicrobial susceptibility than those reported by the hospital antibiogram. This would suggest narrow spectrum antibiotics could still be an effective treatment for uncomplicated cystitis despite this era of antimicrobial resistance. The objective of this study was thus to evaluate the rates of antimicrobial susceptibility of isolates cultured from uncomplicated cystitis cases that presented to the Urology Department of a community hospital in Japan. We evaluated the efficacy of cefaclor, a narrow spectrum antibiotic, for uncomplicated cystitis. We further compared the rates of antimicrobial susceptibility of isolates from uncomplicated cystitis cases to those reported in a hospital-wide antibiogram. A retrospective chart review was performed of patients diagnosed with uncomplicated cystitis in the Urology Department. The patients were mainly treated orally by cefaclor at 750 mg/day for seven days. Significantly greater susceptibilities to cefazolin (87.0% vs 65.7%), trimethoprim-sulfamethoxazole (89.4% vs 79.1%) and levofloxacin (84.6% vs 66.9%) were observed in a cystitis antibiogram for Escherichia coli compared with a hospital-wide antibiogram. The clinical efficacy of cefaclor for acute cystitis was also demonstrated. The greater susceptibility of Escherichia coli to antimicrobials observed in this study supports the hypothesis that antimicrobial susceptibility rates in uncomplicated cystitis cases that present to the Urology Department would be greater than those reported in the hospital antibiogram. Therefore, uncomplicated acute cystitis can be treated by narrow spectrum antibiotics such as cefaclor even in this ''antimicrobial resistance era''.


Assuntos
Anti-Infecciosos/uso terapêutico , Cistite/tratamento farmacológico , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Cistite/microbiologia , Feminino , Hospitais Comunitários/métodos , Humanos , Japão , Levofloxacino/uso terapêutico , Testes de Sensibilidade Microbiana/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Urologia/métodos , Adulto Jovem
2.
Genome Biol Evol ; 8(8): 2288-96, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27389689

RESUMO

The human genome contains thousands of retrocopies, mostly as processed pseudogenes, which were recently shown to be prevalently transcribed. In particular, those specifically acquired in the human lineage are able to modulate gene expression in a manner that contributed to the evolution of human-specific traits. Therefore, knowledge of the human-specific retrocopies that are transcribed or their full-length transcript structure contributes to better understand human genome evolution. In this study, we identified 16 human-specific retrocopies that harbor 5' CpG islands by in silico analysis and showed that 12 were transcribed in normal tissues and cancer cell lines with a variety of expression patterns, including cancer-specific expression. Determination of the structure of the transcripts associated with the retrocopies revealed that none were transcribed from their 5' CpG islands, but rather, from inside the 3' UTR and the nearby 5' flanking region of the retrocopies as well as the promoter of neighboring genes. The multiple forms of the transcripts, such as chimeric and individual transcripts in both the sense and antisense orientation, might have introduced novel post-transcriptional regulation into the genome during human evolution. These results shed light on the potential role of human-specific retrocopies in the evolution of gene regulation and genomic disorders.


Assuntos
RNA Mensageiro/genética , Retroelementos , Regiões 3' não Traduzidas , Linhagem Celular Tumoral , Ilhas de CpG , Regulação Neoplásica da Expressão Gênica , Humanos , Regiões Promotoras Genéticas , Transcrição Reversa
3.
Soft Matter ; 11(19): 3869-74, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25864798

RESUMO

Giant helical (oriented chiral nematic) alignments of microtubules of nanometer to centimeter lengths are known to form over a temperature gradient during anisotropic spiral propagation via tubulin dimer addition in a capillary cell. Such helical alignments may be modified by the addition of either paclitaxel or dimethyl sulfoxide, which induces a lattice (helical) structural change in the microtubule itself. In this study, we found that the lattice structural change of microtubules brings about inversion of microtubule alignments in the helical ordering. Based on microscopy and scattering data, a mechanism for the helical ordering of microtubules is discussed in relation to their lattice (helical) structure.


Assuntos
Microtúbulos/química , Dimetil Sulfóxido/química , Modelos Moleculares , Conformação Molecular , Paclitaxel/química
4.
Small ; 10(9): 1813-20, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24573908

RESUMO

In this paper, we describe stimuli-responsive hydrogels prepared from a rigid rod-like polyelectrolyte 'imogolite' and a dicarboxylic acid. The hydrogel exhibited thixotropy in response to mechanical shock within the order of seconds or sub-seconds. Here, using the latest structural/rheological characterisation techniques, the relationship between the structural transition processes and the shear thinning was estimated. The evidence obtained by the experiments revealed for the first time the direct relationship between the microscopic structural change and the macroscopic thixotropic behavior that have been extensively discussed. The thixotropic hydrogel has the hierarchical architecture in the combination of imogolite and dicarboxylic acid, i.e., sheathed nanotubes/hydroclusters of cross-bridged nanotubes/frameworks. The formation and disintegration of the network structure upon resting and agitating, respectively, were the origin of gel/sol transition (thixotropy), although the hydroclusters of cross-bridged nanotubes were maintained throughout the transition.

5.
Anal Chem ; 84(12): 5292-7, 2012 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-22568496

RESUMO

A microarray chip containing human P450 isoforms was constructed for the parallel assay of their metabolic activities. The chip had microwells that contained vertically integrated P450 and oxygen sensing layers. The oxygen sensing film was made of an organically modified silica film (ORMOSIL) doped with tris(4,7-diphenyl-1,10-phenanthroline) ruthenium dichloride (Ru(dpp)(3)Cl(2)). Human P450s (23 types) expressed in E. coli and purified as membrane fractions were immobilized in agarose matrixes on the oxygen sensing layer. The activities of P450s were determined by evaluating the fluorescence intensity enhancement of the oxygen sensor due to the oxygen consumption by the metabolic reaction. By normalizing the responses with the amounts of oxygen sensor and P450 enzymes in microwells, we could obtain fluorescence enhancement patterns that were characteristic to the combination of P450 isoforms and substrate material. The patterns obtained from two psoralen derivatives resembled each other, whereas a structurally different substrate (capsaicin) resulted in a distinct pattern. These results suggest the potential of the microarray to analyze the activities of diverse P450 isoforms in a high-throughput fashion. Furthermore, mechanism-based inactivation (MBI) of P450 could be detected by successively incubating a chip with different substrate solutions and measuring the residual activities.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Oxigênio/metabolismo , Análise Serial de Proteínas/métodos , Cicloparafinas/química , Humanos , Compostos Organometálicos/química , Fenantrolinas/química , Polímeros/química , Dióxido de Silício/química
6.
Genes Cells ; 15(10): 1036-50, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20825495

RESUMO

Cyclin-dependent protein kinases (CDKs) are required for various cell cycle events both in mitosis and in meiosis. During the meiotic prophase of Saccharomyces cerevisiae, only one CDK, Cdc28, which forms a complex with B-type cyclins, Clb5 or Clb6, promotes not only the onset of premeiotic DNA replication but also the formation of meiotic double-strand breaks (DSBs). In this study, we showed that Cdc28 exhibits punctate staining on chromosomes during meiotic prophase I. Chromosomal localization of Cdc28, dependent on Clb5 and/or Clb6, is frequently observed in zygotene and pachytene, when formation of the synaptonemal complex (SC) occurs. Interestingly, the CDK localization is independent of DSB formation, but rather dependent on meiosis-specific chromosome components such as Red1, Hop1 and a cohesin subunit Rec8. Compromised CDK activity in meiotic prophase leads to defective SC formation without affecting DSB formation. These results suggest that CDK-dependent phosphorylation regulates meiotic chromosome morphogenesis.


Assuntos
Proteína Quinase CDC28 de Saccharomyces cerevisiae/metabolismo , Meiose/fisiologia , Saccharomyces cerevisiae/metabolismo , Complexo Sinaptonêmico/metabolismo , Proteína Quinase CDC28 de Saccharomyces cerevisiae/genética , Cromossomos Fúngicos/genética , Cromossomos Fúngicos/metabolismo , Ciclina B/metabolismo , Prófase Meiótica I/fisiologia , Recombinação Genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiologia , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
7.
Masui ; 58(6): 678-83, 2009 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-19522257

RESUMO

BACKGROUND: Effect of bicarbonated Ringer's solution (BRS) on the liver function of rats with metabolic acidosis was compared with that of lactated Ringer's solution (LRS) and Ringer's solutions (RS). Furthermore, the effect of acidosis on the plasma protein binding ratio of propofol was examined. METHODS: Partial hepatectomized rats were divided into three groups, and BRS, LRS or RS was intravenously administered at 20 ml x kg(-1) x hr(-1) with propofol (45 mg x kg(-1) hr(-1)) for 90 min. Immediately after the administration, indocyanine-green (ICG) was infused. Blood sampling was done at 30, 60, 90 and 120 min after the ICG infusion, and the ICG concentration in plasma was measured. Propofol was added to plasma of rats with ketoacidosis or normal rats (final conc. 5 microg x ml(-1)), and incubated for 30 min at 37 degrees C. After incubation, plasma propofol concentrations were measured. RESULTS: The reduction of ICG in plasma of BRS group was the fastest among the three groups. Plasma protein binding ratio of propofol in plasma samples of rats with ketoacidosis tended to be lower than those of normal rats samples. CONCLUSIONS: These results suggest that metabolic acidosis induced the delay of awakening from anesthesia, suggesting that BRS accelerates recovery from anesthesia through amelioration of acidosis.


Assuntos
Acidose/metabolismo , Período de Recuperação da Anestesia , Soluções Isotônicas/administração & dosagem , Propofol/metabolismo , Animais , Infusões Intravenosas , Masculino , Propofol/administração & dosagem , Propofol/sangue , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Lactato de Ringer , Solução de Ringer , Fatores de Tempo
8.
Mol Biol Cell ; 20(13): 3064-76, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19439448

RESUMO

Spo11-mediated DNA double-strand breaks (DSBs) that initiate meiotic recombination are temporally and spatially controlled. The meiotic cohesin Rec8 has been implicated in regulating DSB formation, but little is known about the features of their interplay. To elucidate this point, we investigated the genome-wide localization of Spo11 in budding yeast during early meiosis by chromatin immunoprecipitation using high-density tiling arrays. We found that Spo11 is dynamically localized to meiotic chromosomes. Spo11 initially accumulated around centromeres and thereafter localized to arm regions as premeiotic S phase proceeded. During this stage, a substantial proportion of Spo11 bound to Rec8 binding sites. Eventually, some of Spo11 further bound to both DSB and Rec8 sites. We also showed that such a change in a distribution of Spo11 is affected by hydroxyurea treatment. Interestingly, deletion of REC8 influences the localization of Spo11 to centromeres and in some of the intervals of the chromosomal arms. Thus, we observed a lack of DSB formation in a region-specific manner. These observations suggest that Rec8 would prearrange the distribution of Spo11 along chromosomes and will provide clues to understanding temporal and spatial regulation of DSB formation.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Cromossomos Fúngicos/genética , DNA Topoisomerases Tipo II/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Sítios de Ligação , Imunoprecipitação da Cromatina , Proteínas Cromossômicas não Histona/genética , Mapeamento Cromossômico , Quebras de DNA de Cadeia Dupla , Replicação do DNA/efeitos dos fármacos , DNA Topoisomerases Tipo II/genética , DNA Fúngico/genética , Endodesoxirribonucleases/genética , Endodesoxirribonucleases/metabolismo , Exodesoxirribonucleases/genética , Exodesoxirribonucleases/metabolismo , Hidroxiureia/farmacologia , Meiose/genética , Mutação , Ligação Proteica , Fase S/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Tempo
9.
J Biol Chem ; 282(7): 4447-4452, 2007 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-17170106

RESUMO

We have determined the activity of all ARSs on the Saccharomyces cerevisiae chromosome VI as chromosomal replication origins in premeiotic S-phase by neutral/neutral two-dimensional gel electrophoresis. The comparison of origin activity of each origin in mitotic and premeiotic S-phase showed that one of the most efficient origins in mitotic S-phase, ARS605, was completely inhibited in premeiotic S-phase. ARS605 is located within the open reading frame of MSH4 gene that is transcribed specifically during an early stage of meiosis. Systematic analysis of relationships between MSH4 transcription and ARS605 origin activity revealed that transcription of MSH4 inhibited the ARS605 origin activity by removing origin recognition complex from ARS605. Deletion of UME6, a transcription factor responsible for repressing MSH4 during mitotic S-phase, resulted in inactivation of ARS605 in mitosis. Our finding is the first demonstration that the transcriptional regulation on the replication origin activity is related to changes in cell physiology. These results may provide insights into changes in replication origin activity in embryonic cell cycle during early developmental stages.


Assuntos
Cromossomos Fúngicos/metabolismo , Replicação do DNA/fisiologia , DNA Fúngico/biossíntese , Meiose/fisiologia , Origem de Replicação/fisiologia , Saccharomyces cerevisiae/fisiologia , Proteínas de Ciclo Celular/genética , Cromossomos Fúngicos/genética , Proteínas de Ligação a DNA/genética , Fases de Leitura Aberta/genética , Proteínas Repressoras/genética , Fase S/fisiologia , Saccharomyces cerevisiae/citologia , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Transcrição/genética , Transcrição Gênica/fisiologia
10.
Cell ; 126(6): 1049-64, 2006 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-16990132

RESUMO

In meiosis, a single round of DNA replication is followed by two consecutive rounds of chromosome segregation, called meiosis I and II. Disjunction of maternal from paternal centromeres during meiosis I depends on the attachment of sister kinetochores to microtubules emanating from the same pole. In budding yeast, monopolar attachment requires recruitment to kinetochores of the monopolin complex. How monopolin promotes monopolar attachment was unclear, as its subunits are poorly conserved and lack similarities to proteins with known functions. We show here that the monopolin subunit Mam1 binds tightly to Hrr25, a highly conserved casein kinase 1 delta/epsilon (CK1delta/epsilon), and recruits it to meiosis I centromeres. Hrr25 kinase activity and Mam1 binding are both essential for monopolar attachment. Since CK1delta/epsilon activity is important for accurate chromosome segregation during meiosis I also in fission yeast, phosphorylation of kinetochore proteins by CK1delta/epsilon might be an evolutionary conserved process required for monopolar attachment.


Assuntos
Caseína Quinase I/metabolismo , Segregação de Cromossomos/fisiologia , Cinetocoros/metabolismo , Meiose/fisiologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimologia , Fuso Acromático/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Caseína Quinase I/genética , Centrômero/genética , Centrômero/metabolismo , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Replicação do DNA/fisiologia , Cinetocoros/ultraestrutura , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismo , Fuso Acromático/genética , Fuso Acromático/ultraestrutura
11.
Curr Genet ; 49(6): 403-13, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16550352

RESUMO

Schizosaccharomyces pombe isp6(+) gene encodes a vacuolar serine protease, which is specifically induced during nitrogen starvation. An isp6-disruption mutant, isp6Delta, grew normally under normal conditions but was defective in large-scale protein degradation during nitrogen starvation, a hallmark of autophagy. Vacuoles are the organelles for such drastic protein degradation but those of isp6Delta were apparently aberrant. isp6Delta was infertile under nitrogen source-free conditions with poor expression of ste11(+), a gene critical for sexual development. A protein kinase A-disruption mutant, pka1Delta, is prone to sexual development because expression of ste11(+) is derepressed. However, isp6Deltapka1Delta still showed defects in ste11(+) expression and sexual development under nitrogen source-free conditions. isp6Delta and isp6Deltapka1Delta were able to initiate sexual development to produce spores when only a small amount of a nitrogen source was present. Pat1 protein kinase negatively controls meiosis, and a temperature-sensitive mutant of pat1, pat1-114, initiates meiosis irrespective of ploidy at the restrictive temperature. However, isp6Deltapat1-114 did not start meiosis under nitrogen source-free conditions even at the restrictive temperature. These observations suggest that isp6(+) contributes to sexual development by providing a nitrogen source through autophagy.


Assuntos
Autofagia/fisiologia , Proteínas de Membrana/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Schizosaccharomyces/fisiologia , Serina Endopeptidases/metabolismo , Autofagia/genética , Epistasia Genética , Regulação Fúngica da Expressão Gênica , Meiose , Proteínas de Membrana/genética , Nitrogênio/deficiência , Nitrogênio/metabolismo , Schizosaccharomyces/citologia , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/genética , Serina Endopeptidases/genética , Transdução de Sinais , Fatores de Transcrição
12.
Nature ; 441(7089): 53-61, 2006 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-16541024

RESUMO

Segregation of homologous maternal and paternal centromeres to opposite poles during meiosis I depends on post-replicative crossing over between homologous non-sister chromatids, which creates chiasmata and therefore bivalent chromosomes. Destruction of sister chromatid cohesion along chromosome arms due to proteolytic cleavage of cohesin's Rec8 subunit by separase resolves chiasmata and thereby triggers the first meiotic division. This produces univalent chromosomes, the chromatids of which are held together by centromeric cohesin that has been protected from separase by shugoshin (Sgo1/MEI-S332) proteins. Here we show in both fission and budding yeast that Sgo1 recruits to centromeres a specific form of protein phosphatase 2A (PP2A). Its inactivation causes loss of centromeric cohesin at anaphase I and random segregation of sister centromeres at the second meiotic division. Artificial recruitment of PP2A to chromosome arms prevents Rec8 phosphorylation and hinders resolution of chiasmata. Our data are consistent with the notion that efficient cleavage of Rec8 requires phosphorylation of cohesin and that this is blocked by PP2A at meiosis I centromeres.


Assuntos
Centrômero/metabolismo , Cromátides/metabolismo , Pareamento Cromossômico , Meiose , Fosfoproteínas Fosfatases/metabolismo , Saccharomyces cerevisiae/citologia , Schizosaccharomyces/citologia , Animais , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Proteínas Cromossômicas não Histona/metabolismo , Sequência Conservada , Humanos , Camundongos , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Fosforilação , Ligação Proteica , Proteína Fosfatase 2 , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/enzimologia , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Coesinas
13.
Curr Biol ; 14(24): 2183-96, 2004 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-15620645

RESUMO

BACKGROUND: Cells undergoing meiosis perform two consecutive divisions after a single round of DNA replication. During the first meiotic division, homologous chromosomes segregate to opposite poles. This is achieved by (1) the pairing of maternal and paternal chromosomes via recombination producing chiasmata, (2) coorientation of homologous chromosomes such that sister chromatids attach to the same spindle pole, and (3) resolution of chiasmata by proteolytic cleavage by separase of the meiotic-specific cohesin Rec8 along chromosome arms. Crucially, cohesin at centromeres is retained to allow sister centromeres to biorient at the second division. Little is known about how these meiosis I-specific events are regulated. RESULTS: Here, we show that Spo13, a centromere-associated protein produced exclusively during meiosis I, is required to prevent sister kinetochore biorientation by facilitating the recruitment of the monopolin complex to kinetochores. Spo13 is also required for the reaccumulation of securin, the persistence of centromeric cohesin during meiosis II, and the maintenance of a metaphase I arrest induced by downregulation of the APC/C activator CDC20. CONCLUSION: Spo13 is a key regulator of several meiosis I events. The presence of Spo13 at centromere-surrounding regions is consistent with the notion that it plays a direct role in both monopolin recruitment to centromeres during meiosis I and maintenance of centromeric cohesion between the meiotic divisions. Spo13 may also limit separase activity after the first division by ensuring securin reaccumulation and, in doing so, preventing precocious removal from chromatin of centromeric cohesin.


Assuntos
Centrômero/metabolismo , Segregação de Cromossomos/fisiologia , Cinetocoros/metabolismo , Meiose/fisiologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Western Blotting , Proteínas de Ciclo Celular/metabolismo , Imunoprecipitação , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Securina , Leveduras
14.
Nature ; 430(6999): 573-8, 2004 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-15229615

RESUMO

Sister chromatids, the products of eukaryotic DNA replication, are held together by the chromosomal cohesin complex after their synthesis. This allows the spindle in mitosis to recognize pairs of replication products for segregation into opposite directions. Cohesin forms large protein rings that may bind DNA strands by encircling them, but the characterization of cohesin binding to chromosomes in vivo has remained vague. We have performed high resolution analysis of cohesin association along budding yeast chromosomes III-VI. Cohesin localizes almost exclusively between genes that are transcribed in converging directions. We find that active transcription positions cohesin at these sites, not the underlying DNA sequence. Cohesin is initially loaded onto chromosomes at separate places, marked by the Scc2/Scc4 cohesin loading complex, from where it appears to slide to its more permanent locations. But even after sister chromatid cohesion is established, changes in transcription lead to repositioning of cohesin. Thus the sites of cohesin binding and therefore probably sister chromatid cohesion, a key architectural feature of mitotic chromosomes, display surprising flexibility. Cohesin localization to places of convergent transcription is conserved in fission yeast, suggesting that it is a common feature of eukaryotic chromosomes.


Assuntos
Cromossomos Fúngicos/metabolismo , Proteínas Nucleares/metabolismo , Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/metabolismo , Transcrição Gênica , Proteínas de Ciclo Celular , Cromátides/genética , Cromátides/metabolismo , Proteínas Cromossômicas não Histona , Segregação de Cromossomos , Cromossomos Fúngicos/genética , Sequência Conservada/genética , DNA Intergênico/genética , DNA Intergênico/metabolismo , Proteínas Fúngicas , Genes Fúngicos/genética , Ligação Proteica , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Schizosaccharomyces/citologia , Schizosaccharomyces/genética , Coesinas
15.
Int J Pharm ; 271(1-2): 225-32, 2004 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15129989

RESUMO

Oral absorption of low molecular weight heparin (LMWH) is limited by its molecular size and negative charge. Development of its oral formulations would allow outpatient treatment with LMWH and decrease the hospital expenses. Studies were aimed at evaluating Labrasol for improving intestinal absorption of LMWH. Formulations containing LMWH and Labrasol were administered to duodenum, jejunum, and ileum of the fasted rats. The doses of LMWH and Labrasol were 200 IU/kg and 50 mg/kg, respectively. Reversibility of absorption enhancing effect of Labrasol was assessed by administering LMWH to jejunum after 0.5 and 1 h of administration of Labrasol. The effect of different doses of Labrasol on LMWH absorption was studied by administering Labrasol at 50, 100, and 200 mg/kg doses. Administration of LMWH formulation tojejunum resulted in the highest plasma anti-Xa activity (0.50+/-0.03 IU/ml) compared to duodenum (0.19+/-0.03 IU/ml), and ileum (0.29 +/-0.06 IU/ml) and the anti-Xa levels were maintained above the therapeutic level for about 160 min. The absorption of LMWH was negligible when LMWH was administered at 0.5 and 1 h post-Labrasol administration. Increasing the dose of Labrasol has decreased the absorption of LMWH from jejunum. Labrasol increased the intestinal absorption of LMWH, and jejunum was found to be the best site of absorption. Intestinal membrane permeability changes induced by Labrasol were transient and reversible. Maintaining high drug concentration gradient across intestinal wall is important to obtain increased intestinal LMWH absorption.


Assuntos
Anticoagulantes/farmacocinética , Emulsões/farmacologia , Heparina de Baixo Peso Molecular/farmacocinética , Absorção Intestinal/efeitos dos fármacos , Animais , Anticoagulantes/administração & dosagem , Área Sob a Curva , Relação Dose-Resposta a Droga , Jejum , Glicerídeos , Heparina de Baixo Peso Molecular/administração & dosagem , Técnicas In Vitro , Intestino Delgado/metabolismo , Masculino , Compostos Orgânicos , Ratos , Ratos Wistar
16.
Biol Pharm Bull ; 27(3): 418-21, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14993814

RESUMO

Intestinal absorption of low molecular weight heparin (LMWH) as well as unfractionated heparin (UFH) is limited due to its large molecular size and extensive negative charge. Development of its oral formulations would allow outpatient treatment with LMWH and UFH, and contribute a reduction in hospital expenses. The present study was aimed at evaluating the absorption enhancers Labrasol and Gelucire 44/14, which mainly consist of glycerides and fatty acids esters, to improve the intestinal absorption of LMWH. The absorption effects of saturated fatty acids with several carbon chain lengths (C6-C14) were also investigated. LMWH formulated with or without absorption enhancer was administered to the duodenum of fasted rats. The doses of LMWH and absorption enhancer were 20 mg/kg and 30 mg/kg, respectively. Plasma anti-Xa activity was measured as a marker of the LMWH absorption. By administration of the LMWH formulation with Labrasol but not with Gelucire 44/14, the plasma anti-Xa activity was increased to a level above 0.2 IU/ml which is the critical level for elucidation of its anticoagulant activity. Saturated fatty acids also enhanced the intestinal absorption of LMWH, and the order of absorption-enhancing effect was C10=C12>C14>C16>C8> or =C6. These results suggest that the intestinal absorption of LMWH varies with carbon chain lengths of the saturated fatty acids.


Assuntos
Adjuvantes Farmacêuticos/farmacologia , Anticoagulantes/farmacocinética , Ácidos Graxos/farmacologia , Heparina de Baixo Peso Molecular/farmacocinética , Absorção Intestinal/efeitos dos fármacos , Animais , Duodeno/metabolismo , Emulsões/farmacologia , Inibidores do Fator Xa , Glicerídeos , Masculino , Compostos Orgânicos , Polietilenoglicóis/farmacologia , Ratos , Ratos Wistar , Fatores de Tempo
17.
Jpn J Pharmacol ; 89(1): 36-43, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12083741

RESUMO

In our previous study, beta-hydroxybutyrate (BHB) was found to prolong survival time and to inhibit cerebral edema by improving energy metabolism in the hypoxia, anoxia and global cerebral ischemia models. In this study, the cerebroprotective effect of BHB was examined in rats with permanent (p)-occlusion and transient (t)-occlusion of middle cerebral artery (MCA). BHB (30 mg x kg(-1) x h(-1) was continuously administered through the femoral vein. In rats with p-MCA occlusion, BHB significantly reduced infarct area at 24 h after the occlusion, but not at 72 h after the occlusion. In rats with 2-h t-MCA occlusion followed by 22-h reperfusion, BHB significantly reduced cerebral infarct area, edema formation, lipid peroxidation and neurological deficits. Moreover, in the t-MCA occlusion model, delayed administration of BHB started at 1 h after the initiation of the MCA occlusion also significantly reduced cerebral infarct area. Taking together the results obtained in our previous study into account, these results indicate that BHB decreased cerebral edema formation and infarct area by improving of the cerebral energy metabolism during ischemia and by inhibition of lipid peroxidation after reperfusion.


Assuntos
Ácido 3-Hidroxibutírico/farmacologia , Isquemia Encefálica/prevenção & controle , Fármacos Neuroprotetores/farmacologia , Animais , Isquemia Encefálica/etiologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Córtex Cerebral/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Infarto da Artéria Cerebral Média/complicações , Infusões Intravenosas , Ataque Isquêmico Transitório/etiologia , Ataque Isquêmico Transitório/metabolismo , Ataque Isquêmico Transitório/patologia , Ataque Isquêmico Transitório/prevenção & controle , Masculino , Artéria Cerebral Média , Ratos , Ratos Wistar , Recuperação de Função Fisiológica
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