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1.
Anticancer Res ; 42(7): 3349-3360, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35790263

RESUMO

BACKGROUND/AIM: The clinical significance ofmiR-4257 in patients with colorectal cancer (CRC) remains unclear. Here, we investigated the usefulness of measuring miR-4257 levels in the plasma and cancer tissues of patients with CRC, and the function of miR-4257 in CRC cell lines. MATERIALS AND METHODS: miR-4257 levels were measured in the plasma and cancer tissues of patients with CRC using quantitative polymerase chain reaction. The relationships between miR-4257 level and clinicopathological features were examined. Proliferation, transwell, wound healing, and adhesion assays were performed using a miR-4257 mimic and inflammatory cytokines. RESULTS: Relapse-free survival was significantly lower in patients with high miR-4257 levels in the plasma and cancer tissue (p<0.001 andp=0.016, respectively). High miR-4257 expression was an independent predictive factor for recurrence (p=0.017 and p=0.028). Addition of inflammatory cytokines to CRC and normal cell lines increased the expression of miR-4257 in the cell lines and cell culture medium. Over-expression of miR-4257 in CRC cells increased malignancy, while over-expression in normal cells increased adhesion to CRC cells. The addition of inflammatory cytokines to normal cell lines enhanced adhesion to CRC cell lines. CONCLUSION: miR-4257 level in plasma and cancer tissues is a biomarker of disease recurrence in patients with CRC. Moreover, miR-4257 promoted tumour growth and was associated with cancer-induced inflammation.


Assuntos
Neoplasias Colorretais , MicroRNAs , Movimento Celular/fisiologia , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Citocinas/genética , Humanos , Inflamação/genética , MicroRNAs/metabolismo , Recidiva Local de Neoplasia
2.
Gan To Kagaku Ryoho ; 49(3): 342-344, 2022 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-35299200

RESUMO

Pancreatic fistula is one of the most critical complication following distal pancreatectomy. We report here a successfully treated case with intractable pancreatic fistula using Trafermin® consisting of basic fibroblast growth factor(bFGF). A 60- year-old man underwent laparoscopic distal pancreatectomy. After surgery, pancreatic fistula was occurred. Pancreatic fistula persisted for 3 months despite of several conservative treatments. After obtaining informed consent, we started to inject 50µg/day of Trafermin® through a drainage tube into the dehiscence of pancreas. Consequently, pancreatic fistula was successfully closed within a week. This technique could be one of the treatment choices for intractable pancreatic fistula following distal pancreatectomy.


Assuntos
Fator 2 de Crescimento de Fibroblastos , Fatores de Crescimento de Fibroblastos , Fístula Pancreática , Fragmentos de Peptídeos , Complicações Pós-Operatórias , Fator 2 de Crescimento de Fibroblastos/uso terapêutico , Fatores de Crescimento de Fibroblastos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatectomia/efeitos adversos , Fístula Pancreática/tratamento farmacológico , Fístula Pancreática/etiologia , Fragmentos de Peptídeos/uso terapêutico , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/etiologia
3.
J Phys Ther Sci ; 33(3): 267-273, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33814715

RESUMO

[Purpose] Global aging has led to a dramatic increase in the number of frail people, who are likely to become bedridden. Since frailty can be partially reversed, early intervention would be beneficial for patients, family members, and clinicians. This study was designed to develop a screening tool for an accurate and comprehensive assessment of frailty by modulating the Edmonton Frail Scale (EFS). [Participants and Methods] The EFS, covering multiple domains, is one of the major diagnostic tools for frailty. Frail and non-frail participants (n=67) were evaluated for each diagnostic item of the EFS to identify the most efficient combination of questions by evaluating its sensitivity and specificity. [Results] The Kyoto Frailty Scale (KFS) was developed as a rapid frailty scale, based on the EFS. The KFS comprises nine questions about health status, polypharmacy, hospitalization, living with a reliable caregiver, shopping, transportation, housework, money management, and forgetting to take medicine. The KFS has an excellent negative predictive value (100%) for screening frailty and a positive predictive value (97%) for screening prefrailty and frailty if we regard KFS ≥4 as a test positive. [Conclusion] The KFS permits clinician to rapidly and accurately screen for frailty and prefrailty, or exclude frailty.

4.
Gan To Kagaku Ryoho ; 48(13): 2109-2111, 2021 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-35045508

RESUMO

Mediastinoscopic esophagectomy(ME)is a minimally invasive approach without thoracotomy and pulmonary atelectasis during surgery. Here, we report the case of a 67-year-old patient who was successfully treated with thoracic esophageal cancer and severe chronic pulmonary infection using ME and home enteral nutrition therapy. Esophageal cancer patients with severe lung dysfunction have a risk of postoperative pneumoniae. ME could be a promising procedure for patients with severe lung dysfunction. We highlight the usefulness of ME as a safe approach to avoid pulmonary complications.


Assuntos
Neoplasias Esofágicas , Esofagectomia , Idoso , Neoplasias Esofágicas/complicações , Neoplasias Esofágicas/cirurgia , Humanos , Pulmão , Mediastinoscópios , Mediastinoscopia , Complicações Pós-Operatórias
5.
Gan To Kagaku Ryoho ; 48(13): 2112-2114, 2021 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-35045509

RESUMO

G-CSF producing esophageal carcinosarcoma is extremely rare, and its effective treatment strategy remains undefined. Here, we report the case of a 69-year-old woman who underwent successful two-stage surgery using mediastinoscopic esophagectomy and laparoscopic reconstruction for the management of severe anemia, malnutrition, and inflammation due to G-CSF producing esophageal carcinosarcoma(G-CSF 265 pg/mL). Chemoradiotherapy could not manage lymph node recurrences in the patient; however, nivolumab was found to be effective and helped achieved a prolonged partial response.


Assuntos
Carcinossarcoma , Neoplasias Esofágicas , Idoso , Carcinossarcoma/tratamento farmacológico , Carcinossarcoma/cirurgia , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/cirurgia , Esofagectomia , Feminino , Fator Estimulador de Colônias de Granulócitos , Humanos , Nivolumabe/uso terapêutico , Recidiva
6.
Gan To Kagaku Ryoho ; 48(13): 1709-1711, 2021 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-35046305

RESUMO

Stage Ⅳ gastric cancer(GC)with ovarian metastasis showed poor prognosis and its treatment strategy remains unclear. Recent studies identified the favorable prognostic effect of conversion surgery in Stage Ⅳ GC following intensive chemotherapy. We report here a case with advanced GC and ovarian metastasis, who underwent conversion surgery for them followed by chemotherapy and had a long-term survival. We reviewed the literatures in order to discuss clinical significance of our treatment strategy.


Assuntos
Tumor de Krukenberg , Neoplasias Ovarianas , Neoplasias Gástricas , Gastrectomia , Humanos , Estadiamento de Neoplasias , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/cirurgia , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia
7.
Gan To Kagaku Ryoho ; 47(13): 2030-2031, 2020 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-33468790

RESUMO

Postoperative low nutrition, body weight loss and poor QOL are pivotal clinical issues for elderly patients following total gastrectomy for advanced gastric cancer. Here, we report a successfully treated high-risk elderly case using home night enteral nutrition and adjuvant chemotherapy following laparoscopic total gastrectomy for advanced gastric cancer. Home night enteral nutrition might not impair oral intake and daily QOL, and could be a useful treatment strategy for elderly patients following total gastrectomy.


Assuntos
Laparoscopia , Neoplasias Gástricas , Idoso , Nutrição Enteral , Gastrectomia , Humanos , Qualidade de Vida , Neoplasias Gástricas/cirurgia
8.
Gan To Kagaku Ryoho ; 47(13): 2056-2058, 2020 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-33468799

RESUMO

TAGS trial revealed the efficacy and safety of trifluridine/tipiracil(Lonsurf®)treatment in patients with metastatic gastric cancer following gastrectomy. Here, we successfully treated 38 months survival case after recurrences following radical gastrectomy for advanced adenocarcinoma of esophago-gastric junction using historical recommended chemotherapy regimens and trifluridine/tipiracil as a fifth-line chemotherapy. Trifluridine/tipiracil therapy contributed to effective and safety treatment even in late-line chemotherapy for recurrent gastric cancer.


Assuntos
Neoplasias Colorretais , Neoplasias Gástricas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Combinação de Medicamentos , Humanos , Recidiva Local de Neoplasia/tratamento farmacológico , Pirrolidinas , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia , Sobreviventes , Timina , Trifluridina/uso terapêutico , Uracila/uso terapêutico
9.
Gan To Kagaku Ryoho ; 47(13): 2424-2426, 2020 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-33468982

RESUMO

A 74-year-old woman presented with abdominal discomfort and was diagnosed with an unresectable advanced gastric cancer(T4aN3aM1, stage Ⅳ)based on a thorough examination. S-1/cisplatin therapy was administered as first-line treatment and paclitaxel/ramucirumab therapy as the second-line treatment. However, because the patient developed a peritoneal dissemination and her lymph node metastasis increased despite these regimens, nivolumab was introduced as a third- line treatment. The CT scan revealed that after the 5 courses of nivolumab, both the peritoneal dissemination and metastatic lymph nodes shrunk; after 12 courses of nivolumab, the peritoneal dissemination almost disappeared. Although nivolumab, an anti-programmed cell death-1(PD-1)antibody, has the possibility to cause immune-related adverse events not seen with conventional chemotherapy, in the present case, these events did not occur and the antitumor effects were maintained for a relatively long period without a decrease in the performance status(PS). We experienced a case of peritoneal metastasis from gastric cancer with a good response to nivolumab. Herein, this case is reported with some literature review.


Assuntos
Neoplasias Peritoneais , Neoplasias Gástricas , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/uso terapêutico , Feminino , Humanos , Metástase Linfática , Nivolumabe/uso terapêutico , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Gástricas/tratamento farmacológico
10.
J Struct Funct Genomics ; 15(3): 173-80, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24894648

RESUMO

The N (1)-methyladenosine residue at position 58 of tRNA is found in the three domains of life, and contributes to the stability of the three-dimensional L-shaped tRNA structure. In thermophilic bacteria, this modification is important for thermal adaptation, and is catalyzed by the tRNA m(1)A58 methyltransferase TrmI, using S-adenosyl-L-methionine (AdoMet) as the methyl donor. We present the 2.2 Å crystal structure of TrmI from the extremely thermophilic bacterium Aquifex aeolicus, in complex with AdoMet. There are four molecules per asymmetric unit, and they form a tetramer. Based on a comparison of the AdoMet binding mode of A. aeolicus TrmI to those of the Thermus thermophilus and Pyrococcus abyssi TrmIs, we discuss their similarities and differences. Although the binding modes to the N6 amino group of the adenine moiety of AdoMet are similar, using the side chains of acidic residues as well as hydrogen bonds, the positions of the amino acid residues involved in binding are diverse among the TrmIs from A. aeolicus, T. thermophilus, and P. abyssi.


Assuntos
Aquifoliaceae/enzimologia , Complexos Multiproteicos/ultraestrutura , S-Adenosilmetionina/química , tRNA Metiltransferases/química , tRNA Metiltransferases/ultraestrutura , Sequência de Aminoácidos , Cristalização , Cristalografia por Raios X , Ligação de Hidrogênio , Dados de Sequência Molecular , Ligação Proteica , Pyrococcus abyssi/enzimologia , Alinhamento de Sequência , Thermus thermophilus/enzimologia
11.
J Biol Chem ; 287(52): 43950-60, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23091054

RESUMO

Post-transcriptional modifications of the wobble uridine (U34) of tRNAs play a critical role in reading NNA/G codons belonging to split codon boxes. In a subset of Escherichia coli tRNA, this wobble uridine is modified to 5-methylaminomethyluridine (mnm(5)U34) through sequential enzymatic reactions. Uridine 34 is first converted to 5-carboxymethylaminomethyluridine (cmnm(5)U34) by the MnmE-MnmG enzyme complex. The cmnm(5)U34 is further modified to mnm(5)U by the bifunctional MnmC protein. In the first reaction, the FAD-dependent oxidase domain (MnmC1) converts cmnm(5)U into 5-aminomethyluridine (nm(5)U34), and this reaction is immediately followed by the methylation of the free amino group into mnm(5)U34 by the S-adenosylmethionine-dependent domain (MnmC2). Aquifex aeolicus lacks a bifunctional MnmC protein fusion and instead encodes the Rossmann-fold protein DUF752, which is homologous to the methyltransferase MnmC2 domain of Escherichia coli MnmC (26% identity). Here, we determined the crystal structure of the A. aeolicus DUF752 protein at 2.5 Å resolution, which revealed that it catalyzes the S-adenosylmethionine-dependent methylation of nm(5)U in vitro, to form mnm(5)U34 in tRNA. We also showed that naturally occurring tRNA from A. aeolicus contains the 5-mnm group attached to the C5 atom of U34. Taken together, these results support the recent proposal of an alternative MnmC1-independent shortcut pathway for producing mnm(5)U34 in tRNAs.


Assuntos
Bactérias/enzimologia , Proteínas de Bactérias/química , tRNA Metiltransferases/química , Bactérias/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cristalografia por Raios X , Metilação , Oxirredutases/química , Oxirredutases/genética , Oxirredutases/metabolismo , Estrutura Terciária de Proteína , RNA Bacteriano/química , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , RNA de Transferência/química , RNA de Transferência/genética , RNA de Transferência/metabolismo , S-Adenosilmetionina/química , S-Adenosilmetionina/genética , S-Adenosilmetionina/metabolismo , Homologia de Sequência de Aminoácidos , tRNA Metiltransferases/genética , tRNA Metiltransferases/metabolismo
12.
Inorg Chem ; 49(15): 6889-96, 2010 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-20597499

RESUMO

Treatment of incomplete cubane-type clusters [(Cp*M){Re(L)}(2)(mu(3)-S)(mu(2)-S)(3)] (M = Ir (1a), Rh (1b); Cp* = eta(5)-C(5)Me(5); L = S(2)C(2)(SiMe(3))(2)) and [{(Pmb)Ru}{Re(L)}(2)(mu(3)-S)(mu(2)-S)(3)] (Pmb = eta(6)-C(6)Me(5)H) with 1 equiv of [Pt(PPh(3))(3)] gave tetranuclear tetra(sulfido) clusters having raft-type cores, [(Cp*M){Pt(PPh(3))(2)}{Re(L)}(2)(mu(3)-S)(4)] (M = Ir (3a), Rh) and [{(Pmb)Ru}{Pt(PPh(3))(2)}{Re(L)}(2)(mu(3)-S)(4)], which presents a sharp contrast to the reactions with [Pd(PPh(3))(4)] reported previously, affording the cubane-type clusters [(Cp*M){Pd(PPh(3))}{Re(L)}(2)(mu(3)-S)(4)] (M = Ir (2a), Rh) and [{(Pmb)Ru}{Pd(PPh(3))}{Re(L)}(2)(mu(3)-S)(4)]. The reactions of 2a with diphosphines P2 resulted in the conversion of its cubane-type core into the analogous raft-type frameworks, forming [(Cp*Ir){Pd(P2)}{Re(L)}(2)(mu(3)-S)(4)] (P2 = cis-Ph(2)PCH=CHPPh(2) (6), Ph(2)PCH(2)CH(2)PPh(2), Ph(2)PCH(2)CH(2)CH(2)PPh(2)). On the other hand, when 2 was allowed to react with Ph(2)PCH(2)PPh(2) (dppm) as P2, the trinuclear tri(sulfido) cluster [(Cp*Ir){Re(L)}(2)(mu(3)-S)(2)(mu(2)-S)(mu(2)-dppm)] (9a) was obtained. Alternatively, this cluster 9a and its Rh analogue 9b were derived from the incomplete cubane-type clusters 1a and 1b by treatment with dppm. It has also been found that further treatment of the cubane-type cluster 2a with excess [Pd(PPh(3))(4)] affords the heptanuclear tetra(sulfido) cluster [(Cp*Ir){Pd(PPh(3))}(4)Re(2)(mu(3)-L)(2)(mu(3)-S)(4)] (10). The detailed structures have been determined by the X-ray analyses for 3a, 6, 9a, and 10.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/química , Metais Pesados/química , Compostos Organometálicos/química , Enxofre/química , Irídio/química , Oxirredução , Paládio/química , Platina/química , Rênio/química , Rutênio/química
13.
Structure ; 15(12): 1642-53, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18073113

RESUMO

In the bacterial genetic-code system, the codon AUA is decoded as isoleucine by tRNA(Ile)(2) with the lysidine residue at the wobble position. Lysidine is derived from cytidine, with ATP and L-lysine, by tRNA(Ile) lysidine synthetase (TilS), which is an N-type ATP pyrophosphatase. In this study, we determined the crystal structure of Aquifex aeolicus TilS, complexed with ATP, Mg2+, and L-lysine, at 2.5 A resolution. The presence of the TilS-specific subdomain causes the active site to have two separate gateways, a large hole and a narrow tunnel on the opposite side. ATP is bound inside the hole, and L-lysine is bound at the entrance of the tunnel. The conserved Asp36 in the PP-motif coordinates Mg2+. In these initial binding modes, the ATP, Mg2+, and L-lysine are held far apart from each other, but they seem to be brought together for the reaction upon cytidine binding, with putative structural changes of the complex.


Assuntos
Trifosfato de Adenosina/metabolismo , Aminoacil-tRNA Sintetases/metabolismo , Lisina/metabolismo , Trifosfato de Adenosina/química , Sequência de Aminoácidos , Aminoacil-tRNA Sintetases/química , Lisina/química , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica , Conformação Proteica , Homologia de Sequência de Aminoácidos
14.
Acta Crystallogr D Biol Crystallogr ; 63(Pt 10): 1059-68, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17881823

RESUMO

Wye bases are tricyclic bases that are found in archaeal and eukaryotic tRNAs. The most modified wye base, wybutosine, which appears at position 37 (the 3'-adjacent position to the anticodon), is known to be important for translational reading-frame maintenance. Saccharomyces cerevisiae TYW1 catalyzes the tri-ring-formation step in wye-base biosynthesis, with the substrate tRNA bearing N(1)-methylated G37. Here, the crystal structure of the archaeal TYW1 homologue from Pyrococcus horikoshii is reported at 2.2 A resolution. The amino-acid sequence of P. horikoshii TYW1 suggested that it is a radical-AdoMet enzyme and the tertiary structure of P. horikoshii TYW1 indeed shares the modified TIM-barrel structure found in other radical-AdoMet enzymes. Radical-AdoMet enzymes generally contain one or two iron-sulfur (FeS) clusters. The tertiary structure of P. horikoshii TYW1 revealed two FeS cluster sites, each containing three cysteine residues. One FeS cluster site was expected from the amino-acid sequence and the other involves cysteine residues that are dispersed throughout the sequence. The existence of two FeS clusters was confirmed from the anomalous Fourier electron-density map. By superposing the P. horikoshii TYW1 tertiary structure on those of other radical-AdoMet enzymes, the AdoMet molecule, which is necessary for the reactions of radical-AdoMet enzymes, was modelled in P. horikoshii TYW1. Surface plots of conservation rates and electrostatic potentials revealed the highly conserved and positively charged active-site hollow. On the basis of the surface properties, a docking model of P. horikoshii TYW1, the tRNA, the FeS clusters and the AdoMet molecule was constructed, with the nucleoside at position 37 of tRNA flipped out from the canonical tRNA structure.


Assuntos
Archaea/metabolismo , Proteínas Arqueais/química , Enzimas/química , Nucleosídeos/química , Sequência de Aminoácidos , Sítios de Ligação , Catálise , Cristalografia por Raios X/métodos , Proteínas Ferro-Enxofre/química , Conformação Molecular , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Pyrococcus horikoshii/metabolismo , Saccharomyces cerevisiae/metabolismo , Homologia de Sequência de Aminoácidos
15.
Proc Natl Acad Sci U S A ; 104(20): 8293-8, 2007 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-17488812

RESUMO

tmRNA and small protein B (SmpB) are essential trans-translation system components. In the present study, we determined the crystal structure of SmpB in complex with the entire tRNA domain of the tmRNA from Thermus thermophilus. Overall, the ribonucleoprotein complex (tRNP) mimics a long-variable-arm tRNA (class II tRNA) in the canonical L-shaped tertiary structure. The tmRNA terminus corresponds to the acceptor and T arms, or the upper part, of tRNA. On the other hand, the SmpB protein simulates the lower part, the anticodon and D stems, of tRNA. Intriguingly, several amino acid residues collaborate with tmRNA bases to reproduce the canonical tRNA core layers. The linker helix of tmRNA had been considered to correspond to the anticodon stem, but the complex structure unambiguously shows that it corresponds to the tRNA variable arm. The tmRNA linker helix, as well as the long variable arm of class II tRNA, may occupy the gap between the large and small ribosomal subunits. This suggested how the tRNA domain is connected to the mRNA domain entering the mRNA channel. A loop of SmpB in the tRNP is likely to participate in the interaction with alanyl-tRNA synthetase, which may be the mechanism for the promotion of tmRNA alanylation by the SmpB protein. Therefore, the tRNP may simulate a tRNA, both structurally and functionally, with respect to aminoacylation and ribosome entry.


Assuntos
Mimetismo Molecular , RNA Bacteriano/química , RNA de Transferência/química , Thermus thermophilus/metabolismo , Alanina/metabolismo , Aminoacilação , Sequência de Bases , Cristalografia por Raios X , Modelos Moleculares , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA Bacteriano/genética , Proteínas de Ligação a RNA/metabolismo , Ribossomos/metabolismo , Relação Estrutura-Atividade
16.
Artigo em Inglês | MEDLINE | ID: mdl-17277442

RESUMO

The transcription termination factor NusA from Aeropyrum pernix was crystallized using a counter-diffusion technique in both terrestrial and microgravity environments. Crystallization under microgravity conditions significantly reduced the twinning content (1.0%) compared with terrestrially grown crystals (18.3%) and improved the maximum resolution from 3.0 to 2.29 A, with similar unit-cell parameters. Based on a comparison of the crystal parameters, the effect of microgravity on protein crystallization is discussed.


Assuntos
Aeropyrum/química , Proteínas Arqueais/química , Fatores de Alongamento de Peptídeos/química , Fatores de Transcrição/química , Cristalografia por Raios X
17.
Biochem Biophys Res Commun ; 355(1): 122-8, 2007 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-17288993

RESUMO

The transcription factor NusA functions in transcriptional regulation involving termination in bacteria. A NusA homolog consisting of only the two KH domains is widely conserved in archaea, but its function remains unknown. We have found that Aeropyrum pernix NusA strongly binds to a certain CU-rich sequence near a termination signal. Our crystal structure of A. pernix NusA revealed that its spatial arrangement is quite similar to that of the KH domains of bacterial NusA. Thus, we consider archaeal NusA to have retained some functions of bacterial NusA, including the ssRNA-binding ability. Remarkable structural differences between archaeal and bacterial NusA exist at the interface with RNAP, in connection with the different NusA-binding sites around the termination signals. Transcriptional termination in archaea could differ from all of the known bacterial and eukaryal mechanisms, in terms of the combination of a bacterial factor and a eukaryal-type RNAP.


Assuntos
Proteínas Arqueais/química , RNA Arqueal/química , RNA Arqueal/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Proteínas Arqueais/metabolismo , Sequência de Bases , Biotinilação , Cristalografia por Raios X , RNA Polimerases Dirigidas por DNA/química , RNA Polimerases Dirigidas por DNA/metabolismo , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/metabolismo , Proteínas Recombinantes/metabolismo
18.
Gan To Kagaku Ryoho ; 34 Suppl 2: 221-2, 2007 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-20443268

RESUMO

The all-in-one catheter package for intravenous hyperalimentation provided an easy handling to the medical staff. However, the package is the cause for a medical cost increase. In order to reduce the medical cost, the incidence of bacterial contamination on the catheter was compared between the two groups: one group is to exchange the catheter once a week and the other is to exchange the catheter twice a week. No bacterial contamination was found in both groups. The result suggested that once a week catheter exchange was tolerable against bacterial contamination.


Assuntos
Infecções Relacionadas a Cateter/microbiologia , Cateterismo/métodos , Contaminação de Equipamentos , Nutrição Parenteral Total/métodos , Humanos , Consentimento Livre e Esclarecido/ética , Fatores de Risco
19.
RNA Biol ; 3(3): 115-22, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17114947

RESUMO

The pseudouridine synthase (Psi synthase) TruA catalyzes the conversion of uridine to pseudouridine at positions 38, 39 and/or 40 in the anticodon stem-loop (ASL) of tRNA. We have determined the crystal structure of TruA from Thermus thermophilus HB8 at 2.25 A resolution. TruA and the other (Psi synthases have a completely conserved active site aspartate, which suggests that the members of this enzyme family share a common catalytic mechanism. The T. thermophilus TruA structure reveals the remarkably flexible structural features in the tRNA-binding cleft, which may be responsible for the primary tRNA interaction. In addition, the charged residues occupying the intermediate positions in the cleft may lead the tRNA to the active site for catalysis. Based on the TruB-tRNA complex structure, the T. thermophilus TruA structure reveals that the tRNA probably makes the melting base pairs move into the cleft, and suggests that a conformational change of the substrate tRNA is necessary to facilitate access to the active site aspartate residue, deep within the cleft.


Assuntos
RNA/genética
20.
Clin Cancer Res ; 12(18): 5363-8, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-17000669

RESUMO

PURPOSE: Hepatocellular carcinoma (HCC) associated with chronic liver disease is known to show an obvious multistage process of tumor progression. We previously identified heat shock protein 70 as a molecular marker of early HCC during investigation of expression profiling in multistage hepatocarcinogenesis. In this report, we examined cyclase-associated protein 2 (CAP2), which is also listed as an up-regulated gene in early HCC. EXPERIMENTAL DESIGN: We measured the level of CAP2 mRNA by real-time quantitative PCR. We raised a polyclonal antibody against CAP2 and we confirmed the expression of CAP2 by immunoblotting and immunohistochemistry in HCC cell lines and HCC tissues. RESULTS: According to real-time quantitative PCR, the level of CAP2 mRNA was up-regulated in early HCC when compared with noncancerous liver tissue, and it was further up-regulated in progressed HCC. We raised a polyclonal antibody against CAP2, which showed a single 53-kDa band of strong intensity in the human HCC cell lines and HCC tissues but only a weak band in the noncancerous liver tissues in Western blot analysis. Immunohistochemical examination of CAP2 revealed its significant overexpression in early HCC when compared with noncancerous and precancerous lesions and in progressed HCC when compared with early HCC. CONCLUSION: Our findings show that CAP2 is up-regulated in HCC when compared with noncancerous and precancerous lesions. This is the first report that proves that CAP2 is up-regulated in human cancers and that this is possibly related to multistage hepatocarcinogenesis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Carcinoma Hepatocelular/metabolismo , Proteínas de Membrana/metabolismo , Biópsia , Western Blotting , Carcinoma Hepatocelular/patologia , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , RNA Mensageiro/metabolismo
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