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1.
Int J Clin Oncol ; 28(9): 1227-1235, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37314600

RESUMO

BACKGROUND: Real-world data on optimal cancer pain management remain scarce. We describe prescription patterns of analgesics in Japanese cancer patients with bone metastases. METHODS: National hospital-based claims data were analyzed. Adults with first diagnosis of cancer during 2015-2019 and first diagnosis of bone metastasis after the initial cancer diagnosis were included. Skeletal-related events (SREs) were identified with disease and receipt codes. RESULTS: Among the 40,507 eligible patients (age [mean ± SD], 69.7 ± 11.7 years), lung (25.3%), prostate (15.6%), breast (10.9%), and colorectal (10.7%) cancers were common primary tumors. Time (mean ± SD) between primary cancer diagnosis and bone metastases was 306.9 ± 490.4 days; median survival time from bone metastases was 483.0 days. Most patients used acetaminophen (62.7%, 117.5 days/year) and nonsteroidal anti-inflammatory drugs (NSAIDs; 75.3%, 170.0 days/year). Commonly used opioids included oxycodone (39.4%; 479.3 days/year), fentanyl (32.5%; 52.6 days/year), morphine (22.1%; 130.9 days/year), and tramadol (15.3%; 143.0 days/year). Internal medicine, surgery, respiratory, urology, and orthopedics treated 19.4%, 18.5%, 17.6%, 17.3%, and 13.0% of patients, respectively. Prescription patterns varied inter-department. Overall, 44.9% of patients developed SRE (bone pain requiring radiation [39.6%] or orthopedic surgery [2.9%]; hypercalcemia, 4.9%; pathological fracture, 3.3%; spinal cord compression, 0.4%). Analgesics use by patients with SREs was 1.8- to 2.2-fold in the postsymptomatic vs the presymptomatic period. SRE patients had numerically lower survival probabilities than non-SRE patients. Opioid use increased considerably in the month before death. CONCLUSION: In Japanese cancer patients with bone metastases, acetaminophen, NSAIDs, and weak or strong opioids were commonly used; their use increased after SREs developed. Opioid use increased closer to death.


Assuntos
Analgésicos Opioides , Neoplasias Ósseas , Adulto , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Analgésicos Opioides/uso terapêutico , Estudos Retrospectivos , Acetaminofen/uso terapêutico , Japão , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/secundário , Analgésicos/uso terapêutico , Dor , Anti-Inflamatórios não Esteroides/uso terapêutico
2.
Int J Biochem Cell Biol ; 79: 151-157, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27590852

RESUMO

We have shown recently that acrolein is strongly involved in cell damage during brain infarction and chronic renal failure. To study the mechanism of acrolein detoxification, we tried to isolate Neuro2a cells with reduced sensitivity to acrolein toxicity (Neuro2a-ATD cells). In one cell line, Neuro2a-ATD1, the level of glutathione (GSH) was increased. We recently isolated a second cell line, Neuro2a-ATD2, and found that acrolein-producing enzymes [polyamine oxidases (PAO); i.e. acetylpolyamine oxidase (AcPAO), and spermine oxidase (SMO)] are reduced in this cell line due to changes at the level of transcription. In the Neuro2a-ATD2 cells, the IC50 of acrolein increased from 4.2 to 6.8µM, and the levels of FosB and C/EBPß - transcription factors involved in the transcription of AcPAO and SMO genes - were reduced. Transfection of siRNAs for FosB and C/EBPß reduced the levels of AcPAO and SMO, respectively. In addition, the synthesis of FosB and AcPAO was also decreased by siRNA for C/EBPß, because C/EBPß is one of the transcription factors for the FosB gene. It was also found that transfection of siRNA for C/EBPß decreased SMO promoter activity in Neuro2a cells but not in ATD2 cells confirming that a decrease in C/EBPß is involved in the reduced SMO activity in Neuro2a-ATD2 cells. Furthermore, transfection of the cDNA for AcPAO or SMO into Neuro2a cells increased the toxicity of acrolein. These results suggest that acrolein is mainly produced from polyamines by PAO.


Assuntos
Acroleína/toxicidade , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Animais , Linhagem Celular Tumoral , DNA Complementar/genética , Camundongos , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Poliamina Oxidase
3.
Int J Biochem Cell Biol ; 76: 87-97, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27163532

RESUMO

Spermidine acetyltransferase (SAT) from Escherichia coli, which catalyses the transfer of acetyl groups from acetyl-CoA to spermidine, is a key enzyme in controlling polyamine levels in prokaryotic cells. In this study, we determined the crystal structure of SAT in complex with spermidine (SPD) and CoA at 2.5Å resolution. SAT is a dodecamer organized as a hexamer of dimers. The secondary structural element and folding topology of the SAT dimer resemble those of spermidine/spermine N(1)-acetyltransferase (SSAT), suggesting an evolutionary link between SAT and SSAT. However, the polyamine specificity of SAT is distinct from that of SSAT and is promiscuous. The SPD molecule is also located at the inter-dimer interface. The distance between SPD and CoA molecules is 13Å. A deep, highly acidic, water-filled cavity encompasses the SPD and CoA binding sites. Structure-based mutagenesis and in-vitro assays identified SPD-bound residues, and the acidic residues lining the walls of the cavity are mostly essential for enzymatic activities. Based on mutagenesis and structural data, we propose an acetylation mechanism underlying promiscuous polyamine recognition for SAT.


Assuntos
Acetiltransferases/química , Poliaminas Biogênicas/química , Proteínas de Escherichia coli/química , Escherichia coli/enzimologia , Multimerização Proteica , Acetilação , Sítios de Ligação , Coenzima A/química , Cristalografia por Raios X , Estrutura Quaternária de Proteína , Especificidade por Substrato
4.
PLoS One ; 10(3): e0120860, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25803296

RESUMO

Shark fin, used as a food, is a rich source of glycosaminoglyans (GAGs), acidic polysaccharides having important biological activities, suggesting their nutraceutical and pharmaceutical application. A comprehensive survey of GAGs derived from the fin was performed on 11 elasmobranchs, including several deep sea sharks. Chondroitin sulfate (CS) and hyaluronic acid (HA) were found in Isurus oxyrinchus, Prionace glauca, Scyliorhinus torazame, Deania calcea, Chlamydoselachus anguineus, Mitsukurina owatoni, Mustelus griseus and Dasyatis akajei, respectively. CS was only found from Chimaera phantasma, Dalatias licha, and Odontaspis ferox, respectively. Characteristic disaccharide units of most of the CS were comprised of C- and D-type units. Interestingly, substantial amount of CS/dermatan sulfate (DS) was found in the dried fin (without skin and cartilage) of Isurus oxyrinchus and Prionace glauca. 1H-NMR analysis showed that the composition of glucuronic acid (GlcA) and iduronic acid (IdoA) in shark CS/DS was 41.2% and 58.8% (Isurus oxyrinchus), 36.1% and 63.9% (Prionace glauca), respectively. Furthermore, a substantial proportion of this CS/DS consisted of E-, B- and D-type units. Shark CS/DS stimulated neurite outgrowth of hippocampal neurons at a similar level as DS derived from invertebrate species. Midkine and pleiotrophin interact strongly with CS/DS from Isurus oxyrinchus and Prionace glauca, affording Kd values of 1.07 nM, 6.25 nM and 1.70 nM, 1.88 nM, respectively. These results strongly suggest that the IdoA-rich domain of CS/DS is required for neurite outgrowth activity. A detailed examination of oligosaccharide residues, produced by chondroitinase ACII digestion, suggested that the IdoA and B-type units as well as A- and C-type units were found in clusters in shark CS/DS. In addition, it was discovered that the contents of B-type units in these IdoA-rich domain increased in a length dependent manner, while C- and D-type units were located particularly in the immediate vicinity of the IdoA-rich domain.


Assuntos
Nadadeiras de Animais/química , Sulfatos de Condroitina/análise , Dermatan Sulfato/análise , Tubarões/anatomia & histologia , Animais , Sulfatos de Condroitina/química , Dermatan Sulfato/química , Dermatan Sulfato/farmacologia , Camundongos , Neuritos/efeitos dos fármacos
5.
Amino Acids ; 47(2): 345-56, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25425115

RESUMO

It is thought that Shine-Dalgarno-like sequences, which exhibit complementarity to the nucleotide sequences at the 3'-end of 18S rRNA, are not present in eukaryotic mRNAs. However, complementary sequences consisting of more than 5 nucleotides to the 3'-end of 18S rRNA, i.e., a CR sequence, are present at -17 to -32 upstream from the initiation codon AUG in 18 mRNAs involved in protein synthesis except eEF1A mRNA. Thus, effects of the CR sequence in mRNAs and polyamines on protein synthesis were examined using control and polyamine-reduced FM3A and NIH3T3 cells. Polyamines did not stimulate protein synthesis encoded by 18 mRNAs possessing a normal CR sequence. When the CR sequence was deleted, protein synthetic activities decreased to less than 70% of intact mRNAs. In eEF1A mRNA, the CR sequence was located at -33 to -39 upstream from the initiation codon AUG, and polyamines stimulated eEF1A synthesis about threefold. When the CR sequence was shifted to -22 to -28 upstream from the AUG, eEF1A synthesis increased in polyamine-reduced cells and the degree of polyamine stimulation decreased greatly. The results indicate that the CR sequence exists in many eukaryotic mRNAs, and the location of a CR sequence in mRNAs influences polyamine stimulation of protein synthesis.


Assuntos
Códon de Iniciação/metabolismo , Fator 1 de Elongação de Peptídeos/biossíntese , Poliaminas/farmacologia , Biossíntese de Proteínas/efeitos dos fármacos , RNA Ribossômico 18S/metabolismo , Animais , Linhagem Celular Tumoral , Códon de Iniciação/genética , Camundongos , Fator 1 de Elongação de Peptídeos/genética , Biossíntese de Proteínas/fisiologia , RNA Ribossômico 18S/genética
6.
Acta Crystallogr F Struct Biol Commun ; 70(Pt 6): 738-41, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24915082

RESUMO

A membrane-associated ATPase, PotA, is a component of the spermidine-preferential uptake system in prokaryotes that plays an important role in normal cell growth by regulating the cellular polyamine concentration. No three-dimensional structures of membrane-associated ATPases in polyamine-uptake systems have been determined to date. Here, the crystallization and preliminary X-ray diffraction analysis of PotA from Thermotoga maritima are reported. Diffraction data were collected and processed to 2.7 Šresolution from both native and selenomethionine-labelled crystals. Preliminary crystallographic analysis revealed that the crystals belonged to the hexagonal space group P3112 (or P3212), with unit-cell parameters a=b=88.9, c=221.2 Å, α=90, ß=90, γ=120°, indicating that a dimer was present in the asymmetric unit.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Membrana/metabolismo , Espermidina/metabolismo , Thermotoga maritima/enzimologia , Adenosina Trifosfatases/química , Sequência de Aminoácidos , Sequência de Bases , Cristalização , Cristalografia por Raios X , Primers do DNA , Proteínas de Membrana/química , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Thermotoga maritima/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-23908034

RESUMO

The spermidine acetyltransferase (SAT) from Escherichia coli catalyses the transfer of acetyl groups from acetyl-CoA to spermidine. SAT has been expressed and purified from E. coli. SAT was crystallized by the sitting-drop vapour-diffusion method to obtain a more detailed insight into the molecular mechanism. Preliminary X-ray diffraction studies revealed that the crystals diffracted to 2.5 Å resolution and belonged to the cubic space group P23, with unit-cell parameters a = b = c = 148.7 Å. They contained four molecules per asymmetric unit.


Assuntos
Acetiltransferases/biossíntese , Acetiltransferases/isolamento & purificação , Proteínas de Escherichia coli/biossíntese , Proteínas de Escherichia coli/isolamento & purificação , Escherichia coli/enzimologia , Regulação Bacteriana da Expressão Gênica , Acetiltransferases/química , Cristalização , Cristalografia por Raios X , Proteínas de Escherichia coli/química
9.
Biochem Biophys Res Commun ; 430(4): 1265-71, 2013 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-23261472

RESUMO

We have recently reported that acrolein is more toxic than reactive oxygen species. Thus, the mechanism of cell toxicity by acrolein was studied using mouse mammary carcinoma FM3A cells. Acrolein-conjugated proteins were separated by gel electrophoresis with subsequent determination of their amino acid sequence, and it was found that glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was one of the major acrolein-conjugated proteins in cells. Acrolein interacted with cysteine-150 at the active site of GAPDH, and also with cysteine-282. When cells were treated with 8 µM acrolein, the activity of acrolein-conjugated GAPDH was greatly reduced, and the ATP content in cells was thus significantly reduced. In addition, it was shown that acrolein-conjugated GAPDH translocated to the nucleus, and the level of acetylated GAPDH and the number of TUNEL positive cells was increased, indicating that cell death is enhanced by acrolein-conjugated GAPDH. Inhibition of cell growth by acrolein was partially reversed when the cDNA encoding GAPDH was transformed into cells. These results indicate that inactivation of GAPDH is one mechanism that underlies cell toxicity caused by acrolein.


Assuntos
Acroleína/metabolismo , Acroleína/toxicidade , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular Tumoral , Cisteína/genética , Cisteína/metabolismo , Gliceraldeído-3-Fosfato Desidrogenases/genética , Camundongos , Dados de Sequência Molecular , Transformação Genética
10.
Int J Biochem Cell Biol ; 44(11): 1877-86, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22814172

RESUMO

We have reported that polyamines increase cell viability at the stationary phase of cell growth through translational stimulation of ribosome modulation factor, and SpoT and RpoZ proteins involved in the synthesis and function of ppGpp in Escherichia coli. Since biofilm formation is also involved in cell viability, we looked for proteins involved in biofilm formation and cell viability whose synthesis is stimulated by polyamines at the level of translation. It was found that the synthesis of response regulators UvrY and CpxR in the two-component signal transducing systems and ribosome recycling factor (RRF) was increased by polyamines at the level of translation. Polyamine stimulation of the synthesis of UvrY and RRF was dependent on the existence of the inefficient initiation codons UUG and GUG in uvrY and frr mRNA, respectively; and polyamine stimulation of CpxR synthesis was dependent on the existence of an unusual location of a Shine-Dalgarno (SD) sequence in cpxR mRNA. Biofilm formation and cell viability in the absence of polyamines was increased by transformation of modified uvrY and cpxR genes, and cell viability by modified frr gene whose translation occurs effectively without polyamines. The results indicate that polyamines are necessary for both biofilm formation and cell viability.


Assuntos
Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Proteínas de Escherichia coli/metabolismo , Viabilidade Microbiana/efeitos dos fármacos , Poliaminas/farmacologia , Proteínas Ribossômicas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Proteínas de Bactérias/genética , Sequência de Bases , Biofilmes/efeitos dos fármacos , Dicroísmo Circular , Cobre/farmacologia , Escherichia coli/citologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/fisiologia , Proteínas de Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Genes Bacterianos/genética , Modelos Biológicos , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espermidina/farmacologia , Fatores de Transcrição/genética
11.
J Pharmacol Exp Ther ; 343(1): 82-90, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22743575

RESUMO

Modeling the binding sites for spermine and ifenprodil on the regulatory (R) domains of the N-methyl-D-aspartate receptor GluN1 and GluN2B subunits was carried out after measuring spermine stimulation and ifenprodil inhibition at receptors containing GluN1 and GluN2B R domain mutants. Models were constructed based on the published crystal structure of the GluN1 and GluN2B R domains, which form a heterodimer (Nature 475:249-253, 2011). The experimental results and modeling suggest that a binding site for spermine was formed by the residues near the cleft between the R1 and R2 lobes of the GluN1 R domain (GluN1R) together with residues on the surface of the R2 (C-terminal side) lobe of the GluN2B R domain (GluN2BR). The ifenprodil binding site included residues on the surface of the R1 lobe (N-terminal side) of GluN1R together with residues near the cleft between the R1 and R2 lobes of GluN2BR. It was confirmed using a Western blot analysis that GluN1R and GluN2BR formed a heterodimer. Models of spermine and ifenprodil binding to the heterodimer were constructed. The modeling suggests that an open space between the two R1 lobes of GluN1R and GluN2BR is promoted through spermine binding and that the R1 lobes of GluN1R and GluN2BR approach each other through ifenprodil binding--an effect opposite to that seen with the binding of spermine.


Assuntos
Piperidinas/metabolismo , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/metabolismo , Espermina/metabolismo , Sequência de Aminoácidos , Animais , Feminino , Dados de Sequência Molecular , Piperidinas/química , Ligação Proteica/fisiologia , Multimerização Proteica/fisiologia , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Subunidades Proteicas/química , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Ratos , Receptores de N-Metil-D-Aspartato/genética , Espermina/química , Xenopus laevis
12.
Clin Chim Acta ; 413(7-8): 753-9, 2012 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-22293277

RESUMO

BACKGROUND: We found previously that increases in plasma levels of protein-conjugated acrolein and polyamine oxidases, enzymes that produce acrolein, are good biomarkers for stroke. The aim of this study was to test whether 3-hydroxypropyl mercapturic acid (3-HPMA), an acrolein-glutathione metabolite, was increased in the urine of stroke patients. METHODS: The level of 3-HPMA in urine was measured by liquid chromatography with tandem mass spectrometry (LC-MS/MS). Stroke (78 subjects) was divided into 52 cerebral infarction (CI) and 26 cerebral hemorrhage (CH) on the basis of clinical information including brain imaging. RESULTS: A major acrolein derivative in urine is 3-HPMA. Being different from the results of PC-Acro in plasma, 3-HPMA in urine decreased following stroke. The median value of µmol 3-HPMA/g creatinine (Cre) for 90 control subjects was 2.83, while that for 78 stroke patients was 1.56. The degree of the decrease in 3-HPMA was similar in both CI and CH patients. Furthermore, the median value of µmol 3-HPMA/g Cre in 56 patients with lesions ≥ 1cm in diameter (1.39) was significantly lower than that in 20 patients with lesion <1cm in diameter (2.16). CONCLUSION: Inverse correlation between stroke and urinary 3-HPMA was observed. The results suggest that stroke is aggravated when nervous system tissues have a reduced level of glutathione.


Assuntos
Acetilcisteína/análogos & derivados , Acroleína/metabolismo , Glutationa/metabolismo , Acidente Vascular Cerebral/urina , Acetilcisteína/urina , Adulto , Idoso , Estudos de Casos e Controles , Cromatografia Líquida , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem
13.
Biochem Biophys Res Commun ; 418(1): 110-5, 2012 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-22244891

RESUMO

We have shown recently that acrolein is more strongly involved in cell damage than reactive oxygen species during brain infarction. Thus, we tried to isolate cells with reduced susceptibility to acrolein toxicity to clarify how acrolein is detoxified under cell culture conditions. The IC(50) of acrolein in mouse mammary carcinoma FM3A cells and in neuroblastoma Neuro2a cells was 2.6 and 4.2µM, respectively, but in acrolein toxicity-decreasing FM3A (FM3A-ATD) cells and Neuro2a (Neuro2a-ATD) cells, it was 7.6 and 8.4µM, respectively. In both FM3A-ATD and Neuro2a-ATD cells, the concentration of glutathione (GSH) was increased, so that detoxification occurred through acrolein conjugation with GSH. In FM3A-ATD cells, the level of a rate-limiting enzyme of GSH synthesis, γ-glutamylcysteine ligase catalytic unit (GCLC), was increased through the reactivation of one inactive allele of GCLC genes in FM3A cells. In Neuro2a-ATD cells, phosphorylation of transcription factors (c-Jun and NF-κB) necessary for expression of genes for GCLC and glutathione synthetase (GSHS) involved in GSH synthesis was stimulated, so that transcription of two genes increased in Neuro2a-ATD cells. Phosphorylation of JNK (c-Jun N-terminal kinase), which catalyzes phosphorylation of c-Jun and NF-κB p65, was also increased in Neuro2a-ATD cells, suggesting that activation of JNK kinase is responsible for the increase in GSH. These results support the idea that GSH plays important roles in detoxification of acrolein, because GSH is increased in both FM3A-ATD and Neuro2a-ATD cells.


Assuntos
Acroleína/antagonistas & inibidores , Acroleína/metabolismo , Regulação Enzimológica da Expressão Gênica , Glutamato-Cisteína Ligase/genética , Glutationa/biossíntese , Estresse Oxidativo , Acroleína/toxicidade , Animais , Sequência de Bases , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Separação Celular , Éxons , Íntrons , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos , Dados de Sequência Molecular , NF-kappa B/metabolismo , Fosforilação
14.
Int J Biochem Cell Biol ; 44(2): 412-22, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22138225

RESUMO

It is known that polyamines increase cell growth through stimulation of the synthesis of several kinds of proteins encoded by the so-called "polyamine modulon". We recently reported that polyamines also increase cell viability at the stationary phase of cell growth through stimulation of the synthesis of ribosome modulation factor, a component of the polyamine modulon. Accordingly, we looked for other proteins involved in cell viability whose synthesis is stimulated by polyamines. It was found that the synthesis of ppGpp regulatory protein (SpoT) and ω protein of RNA polymerase (RpoZ) was stimulated by polyamines at the level of translation. Stimulation of the synthesis of SpoT and RpoZ by polyamines was due to an inefficient initiation codon UUG in spoT mRNA and an unusual location of a Shine-Dalgarno (SD) sequence in rpoZ mRNA. Accordingly, the spoT and rpoZ genes are components of the polyamine modulon involved in cell viability. Reduced cell viability caused by polyamine deficiency was prevented by modified spoT and rpoZ genes whose synthesis was not influenced by polyamines. Under these conditions, the level of ppGpp increased in parallel with increase of SpoT protein. The results indicate that polyamine stimulation of synthesis of SpoT and RpoZ plays important roles for cell viability through stimulation of ppGpp synthesis by SpoT and modulation of RNA synthesis by ppGpp-RpoZ complex.


Assuntos
RNA Polimerases Dirigidas por DNA/fisiologia , Proteínas de Escherichia coli/fisiologia , Poliaminas/farmacologia , Pirofosfatases/fisiologia , RNA Polimerases Dirigidas por DNA/biossíntese , RNA Polimerases Dirigidas por DNA/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/biossíntese , Proteínas de Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Guanosina Tetrafosfato/metabolismo , Viabilidade Microbiana/efeitos dos fármacos , Pirofosfatases/biossíntese , Pirofosfatases/genética , RNA Bacteriano/genética , RNA Bacteriano/metabolismo
15.
Amino Acids ; 42(2-3): 733-40, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21796432

RESUMO

The structure and function of a cadaverine-lysine antiporter CadB and a putrescine-ornithine antiporter PotE in Escherichia coli were evaluated using model structures based on the crystal structure of AdiC, an agmatine-arginine antiporter, and the activities of various CadB and PotE mutants. The central cavity of CadB, containing the substrate binding site, was wider than that of PotE, mirroring the different sizes of cadaverine and putrescine. The size of the central cavity of CadB and PotE was dependent on the angle of transmembrane helix 6 (TM6) against the periplasm. Tyr(73), Tyr(89), Tyr(90), Glu(204), Tyr(235), Asp(303), and Tyr(423) of CadB, and Cys(62), Trp(201), Glu(207), Trp(292), and Tyr(425) of PotE were strongly involved in the antiport activities. In addition, Trp(43), Tyr(57), Tyr(107), Tyr(366), and Tyr(368) of CadB were involved preferentially in cadaverine uptake at neutral pH, while only Tyr(90) of PotE was involved preferentially in putrescine uptake. The results indicate that the central cavity of CadB consists of TMs 2, 3, 6, 7, 8, and 10, and that of PotE consists of TMs 2, 3, 6, and 8. These results also suggest that several amino acid residues are necessary for recognition of cadaverine in the periplasm because the level of cadaverine is much lower than that of putrescine in the periplasm at neutral pH. All the amino acid residues identified as being strongly involved in both the antiport and uptake activities were located on the surface of the transport path consisting of the central cavity and TM12.


Assuntos
Sistemas de Transporte de Aminoácidos/metabolismo , Antiporters/metabolismo , Poliaminas Biogênicas/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Sequência de Aminoácidos , Sistemas de Transporte de Aminoácidos/química , Antiporters/química , Cristalografia por Raios X , Proteínas de Escherichia coli/química , Dados de Sequência Molecular , Conformação Proteica , Homologia de Sequência de Aminoácidos
16.
Chem Commun (Camb) ; 47(37): 10344-6, 2011 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21853178

RESUMO

An amphiphilic low-molecular-weight hydrogelator 1 was synthesized. A tris-glycine-SDS solution gel of 1 was applied for electrophoresis to separate proteins. Centrifugation of a mixture of protein and a hydrogel of 1 enabled the recovery of protein. Various combinations of proteins were applied for supramolecular gel electrophoresis (SUGE), and remarkably poor mobility for small proteins (<45 kDa) was found.


Assuntos
Eletroforese/métodos , Compostos Orgânicos/química , Proteínas/isolamento & purificação , Interações Hidrofóbicas e Hidrofílicas , Peso Molecular , Compostos Orgânicos/síntese química
17.
Am J Hum Genet ; 88(3): 306-16, 2011 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-21376300

RESUMO

Little is known about the genetics of nonsyndromic intellectual disability (NSID). We hypothesized that de novo mutations (DNMs) in synaptic genes explain an important fraction of sporadic NSID cases. In order to investigate this possibility, we sequenced 197 genes encoding glutamate receptors and a large subset of their known interacting proteins in 95 sporadic cases of NSID. We found 11 DNMs, including ten potentially deleterious mutations (three nonsense, two splicing, one frameshift, four missense) and one neutral mutation (silent) in eight different genes. Calculation of point-substitution DNM rates per functional and neutral site showed significant excess of functional DNMs compared to neutral ones. De novo truncating and/or splicing mutations in SYNGAP1, STXBP1, and SHANK3 were found in six patients and are likely to be pathogenic. De novo missense mutations were found in KIF1A, GRIN1, CACNG2, and EPB41L1. Functional studies showed that all these missense mutations affect protein function in cell culture systems, suggesting that they may be pathogenic. Sequencing these four genes in 50 additional sporadic cases of NSID identified a second DNM in GRIN1 (c.1679_1681dup/p.Ser560dup). This mutation also affects protein function, consistent with structural predictions. None of these mutations or any other DNMs were identified in these genes in 285 healthy controls. This study highlights the importance of the glutamate receptor complexes in NSID and further supports the role of DNMs in this disorder.


Assuntos
Ácido Glutâmico/genética , Deficiência Intelectual/genética , Mutação/genética , Substituição de Aminoácidos/genética , Animais , Sequência de Bases , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Feminino , Células HEK293 , Humanos , Cinesinas/genética , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mutação de Sentido Incorreto/genética , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Fenótipo , Ligação Proteica/genética , Transporte Proteico , Splicing de RNA/genética , Ratos , Receptores de AMPA/metabolismo , Receptores de N-Metil-D-Aspartato/genética , Frações Subcelulares/metabolismo , Síndrome
18.
Clin Chim Acta ; 412(3-4): 339-42, 2011 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-21070758

RESUMO

BACKGROUND: We have recently found that the median relative risk value (RRV) (0-1) of brain infarction estimated by protein-conjugated acrolein (PC-Acro), IL-6 and CRP together with age was in the order silent brain infarction (SBI) (0.80)>carotid atherosclerosis (CA) (0.76)>white matter hyperintensity (WMH) (0.46)>control (0.14). We clarified how metabolic disorders [hypertension (HT), hyperlipidemia (HL) and hyperglycemia (HG)] are correlated with RRV. METHODS: The levels of PC-Acro, IL-6 and CRP in plasma were measured by ELISA. SBI and WMH were evaluated by MRI, and CA was evaluated by duplex carotid ultrasonography. RESULTS: The median RRV of metabolic disorders was in the order HT+HG (0.84)>HT+HL (0.73)>HT (0.65)≈HG (0.65)>HL (0.61)>HL+HG (0.48)>no metabolic disorder (0.24)>normal (0.11). Correlation with SBI was in the order HT+HG (52%)>HT+HL (42%)>HT (40%)>HG (34%)≈HL(33%)>HL+HG (14%)≈no metabolic disorder (14%). CONCLUSION: The results indicate that HT is the most strongly associated factor with SBI among metabolic disorders and that the seriousness of metabolic disorder estimated by RRV was well correlated with SBI.


Assuntos
Acroleína/metabolismo , Infarto Encefálico/complicações , Proteína C-Reativa/metabolismo , Interleucina-6/metabolismo , Doenças Metabólicas/metabolismo , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Artérias Carótidas/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Doenças Metabólicas/complicações , Doenças Metabólicas/diagnóstico por imagem , Doenças Metabólicas/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Ultrassonografia
19.
J Biol Chem ; 285(37): 28698-707, 2010 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-20628056

RESUMO

We searched for proteins whose synthesis is enhanced by polyamines at the stationary phase of cell growth using an Escherichia coli polyamine-requiring mutant in which cell viability is greatly decreased by polyamine deficiency. The synthesis of ribosome modulation factor (RMF) was strongly enhanced by polyamines at the level of translation at the stationary phase of cell growth. In rmf mRNA, a Shine-Dalgarno (SD) sequence is located 11 nucleotides upstream of the initiation codon AUG. When the SD sequence was moved to the more common position 8 nucleotides upstream of the initiation codon, the degree of polyamine stimulation was reduced, although the level of RMF synthesis was markedly increased. Polyamine stimulation of RMF synthesis was found to be caused by a selective structural change of the bulged-out region of the initiation site of rmf mRNA. The decrease in cell viability caused by polyamine deficiency was prevented by the addition of a modified rmf gene whose synthesis is not influenced by polyamines. The results indicate that polyamines enhance cell viability of E. coli at least in part by enhancing RMF synthesis.


Assuntos
Poliaminas Biogênicas , Códon de Iniciação/metabolismo , Proteínas de Escherichia coli/biossíntese , Escherichia coli/metabolismo , RNA Bacteriano/metabolismo , Sequências Reguladoras de Ácido Ribonucleico/fisiologia , Proteínas Ribossômicas/biossíntese , Poliaminas Biogênicas/metabolismo , Poliaminas Biogênicas/farmacologia , Códon de Iniciação/genética , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas Ribossômicas/genética
20.
Atherosclerosis ; 211(2): 475-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20417516

RESUMO

OBJECTIVE: We found previously that the measurement of plasma levels of protein-conjugated acrolein (PC-Acro) together with IL-6 and CRP can be used to identify silent brain infarction (SBI) with high sensitivity and specificity. The aim of this study was to clarify how three biochemical markers are correlated to SBI, carotid atherosclerosis (CA) and white matter hyperintensity (WMH). METHODS: The levels of PC-Acro, IL-6 and CRP in plasma were measured by ELISA. SBI and WMH were evaluated by MRI, and CA was evaluated by duplex carotid ultrasonography. RESULTS: A total of 790 apparently healthy volunteers were classified into 260 control, 214 SBI, 263 CA and 245 WMH subjects, which included 187 subjects with two or three pathologies. When the combined measurements of PC-Acro, IL-6 and CRP were evaluated together with age, using a receiver operating characteristic curve and artificial neural networks, the relative risk value (RRV), an indicator of tissue damage, was in the order SBI with CA (0.90)>SBI (0.80)>CA (0.76)>WMH with CA (0.65)>WMH (0.46)>control (0.14). RRV was also correlated with severity in each group of SBI, CA and WMH. CONCLUSION: The RRV supports the idea that the degree of risk to develop a stroke is in the order SBI>CA>WMH.


Assuntos
Acroleína/sangue , Infarto Encefálico/patologia , Encéfalo/patologia , Proteína C-Reativa/biossíntese , Doenças das Artérias Carótidas/patologia , Interleucina-6/sangue , Fibras Nervosas Mielinizadas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Encefalopatias/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Redes Neurais de Computação , Fatores de Risco
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