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1.
Mol Psychiatry ; 23(4): 985-992, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28827761

RESUMO

Working memory capacity, a critical component of executive function, expands developmentally from childhood through adulthood. Anomalies in this developmental process are seen in individuals with autism spectrum disorder (ASD), schizophrenia and intellectual disabilities (ID), implicating this atypical process in the trajectory of developmental neuropsychiatric disorders. However, the cellular and neuronal substrates underlying this process are not understood. Duplication and triplication of copy number variants of 22q11.2 are consistently and robustly associated with cognitive deficits of ASD and ID in humans, and overexpression of small 22q11.2 segments recapitulates dimensional aspects of developmental neuropsychiatric disorders in mice. We capitalized on these two lines of evidence to delve into the cellular substrates for this atypical development of working memory. Using a region- and cell-type-selective gene expression approach, we demonstrated that copy number elevations of catechol-O-methyl-transferase (COMT) or Tbx1, two genes encoded in the two small 22q11.2 segments, in adult neural stem/progenitor cells in the hippocampus prevents the developmental maturation of working memory capacity in mice. Moreover, copy number elevations of COMT or Tbx1 reduced the proliferation of adult neural stem/progenitor cells in a cell-autonomous manner in vitro and migration of their progenies in the hippocampus granular layer in vivo. Our data provide evidence for the novel hypothesis that copy number elevations of these 22q11.2 genes alter the developmental trajectory of working memory capacity via suboptimal adult neurogenesis in the hippocampus.


Assuntos
Hipocampo/citologia , Memória de Curto Prazo/fisiologia , Células-Tronco Neurais/citologia , Neurogênese/genética , Neurônios/citologia , Animais , Transtorno do Espectro Autista/genética , Catecol O-Metiltransferase/genética , Cromossomos Humanos Par 22 , Variações do Número de Cópias de DNA , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/patologia , Células HEK293 , Hipocampo/metabolismo , Humanos , Deficiência Intelectual/genética , Deficiência Intelectual/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Esquizofrenia/genética , Proteínas com Domínio T/genética
2.
Mol Psychiatry ; 19(1): 55-62, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23183491

RESUMO

Opioids, such as morphine and fentanyl, are widely used as effective analgesics for the treatment of acute and chronic pain. In addition, the opioid system has a key role in the rewarding effects of morphine, ethanol, cocaine and various other drugs. Although opioid sensitivity is well known to vary widely among individual subjects, several candidate genetic polymorphisms reported so far are not sufficient for fully understanding the wide range of interindividual differences in human opioid sensitivity. By conducting a multistage genome-wide association study (GWAS) in healthy subjects, we found that genetic polymorphisms within a linkage disequilibrium block that spans 2q33.3-2q34 were strongly associated with the requirements for postoperative opioid analgesics after painful cosmetic surgery. The C allele of the best candidate single-nucleotide polymorphism (SNP), rs2952768, was associated with more analgesic requirements, and consistent results were obtained in patients who underwent abdominal surgery. In addition, carriers of the C allele in this SNP exhibited less vulnerability to severe drug dependence in patients with methamphetamine dependence, alcohol dependence, and eating disorders and a lower 'Reward Dependence' score on a personality questionnaire in healthy subjects. Furthermore, the C/C genotype of this SNP was significantly associated with the elevated expression of a neighboring gene, CREB1. These results show that SNPs in this locus are the most potent genetic factors associated with human opioid sensitivity known to date, affecting both the efficacy of opioid analgesics and liability to severe substance dependence. Our findings provide valuable information for the personalized treatment of pain and drug dependence.


Assuntos
Analgésicos Opioides/administração & dosagem , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/genética , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromossomos Humanos Par 2/genética , Metilases de Modificação do DNA/genética , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/etiologia , Escalas de Graduação Psiquiátrica , Procedimentos de Cirurgia Plástica/efeitos adversos , Transtornos Relacionados ao Uso de Substâncias/genética , Adulto Jovem
3.
Br J Anaesth ; 115(1): 122-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25835024

RESUMO

BACKGROUND: Train-of-four (TOF) fade during nerve-mediated muscle contraction is postulated to be attributable to inhibition of prejunctional nicotinic α3ß2 acetylcholine receptors (nAChRs), while decrease of twitch tension is attributable to block of postjunctional muscle nAChRs. The validity of these presumptions was tested using specific prejunctional and postjunctional nAChR antagonists, testing the hypothesis that fade is not always a prejunctional phenomenon. METHODS: Pentobarbital anaesthetized mice had TOF fade measured after administration of: either 0.9% saline; the prejunctional α3ß2 nAChR antagonist, dihydro-ß-erythroidine (DHßE); the postjunctional nAChR antagonists, α-bungarotoxin (α-BTX) or α-conotoxin GI; and a combination of α-BTX and DHßE; or a combination of α-conotoxin GI and DHßE. RESULTS: Saline caused no neuromuscular changes. Administration of muscle nAChR antagonists, α-BTX or α-conotoxin GI caused significant decrease of twitch tension and TOF fade compared with baseline (P<0.01). DHßE alone caused no change of twitch tension or fade even after 90 min, but its coadministration with α-BTX or α-conotoxin GI significantly accelerated the onset of paralysis and degree of fade compared with α-BTX or α-conotoxin GI alone (P<0.01). CONCLUSIONS: Occupation of postjunctional nAChRs alone by α-BTX or α-conotoxin GI causes fade. As the prejunctional effects of DHßE on fade became manifest only when co-administered with α-BTX or α-conotoxin GI, specific inhibition of prejunctional nAChR alone is not necessary and sufficient to cause fade. Fade observed during repetitive nerve stimulation can be because of block of either postjunctional nAChRs alone, or block of prejunctional and postjunctional nAChRs together.


Assuntos
Estimulação Elétrica , Contração Muscular/efeitos dos fármacos , Junção Neuromuscular/efeitos dos fármacos , Receptores Colinérgicos/efeitos dos fármacos , Animais , Bungarotoxinas/administração & dosagem , Conotoxinas/administração & dosagem , Di-Hidro-beta-Eritroidina/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Cloreto de Sódio/administração & dosagem
4.
Osteoporos Int ; 25(9): 2245-53, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24899103

RESUMO

UNLABELLED: This multi-center, prospective, open-label, observational study evaluated the effects of once-monthly minodronate (50 mg) on treatment persistence, bone turnover markers, bone mineral density, low back pain, and upper gastrointestinal symptoms in outpatients with osteoporosis previously treated with daily or weekly bisphosphonate products. INTRODUCTION: The purposes of this study were to investigate the effects of once-monthly oral minodronate (MIN 50 mg) on bone turnover markers and bone mineral density, low back pain, and upper gastrointestinal symptoms, as well as preference for and treatment persistence of MIN 50 mg among Japanese osteoporosis patients currently treated with daily or weekly bisphosphonates. METHODS: Study patients were allocated based on their preference to either the Switch group (patients willing to switch over to MIN 50 mg) or the Continue group (patients wanting to continue their current therapies). Patients' treatment persistence and satisfaction levels with the therapies were assessed using a self-administered questionnaire. The study endpoints were serum TRACP-5b, serum P1NP, bone mineral density, upper gastrointestinal symptoms, and low back pain. RESULTS: In total, 264 and 133 patients were allocated into the Switch and Continue groups, respectively. Approximately, 65 % of patients were willing to switch to MIN 50 mg, with the predominant reason being "less frequent dosing more convenient." Treatment persistence was significantly higher in the Switch group (MIN 50 mg) than the Continue group. Almost all patients with abnormal bone metabolism markers demonstrated normalization after switchover. MIN 50 mg alleviated low back pain and upper gastrointestinal symptoms induced by prior bisphosphonate use. CONCLUSIONS: MIN 50 mg alleviates low back pain, reduces bone turnover markers and increases bone density, and induces fewer upper gastrointestinal symptoms after switchover from prior bisphosphonate products, and therefore, it may provide patients with a more convenient treatment option and enhance long-term treatment persistence.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Difosfonatos/uso terapêutico , Imidazóis/administração & dosagem , Osteoporose/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/efeitos adversos , Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/administração & dosagem , Difosfonatos/efeitos adversos , Esquema de Medicação , Substituição de Medicamentos , Feminino , Gastroenteropatias/induzido quimicamente , Humanos , Imidazóis/efeitos adversos , Imidazóis/uso terapêutico , Dor Lombar/etiologia , Dor Lombar/prevenção & controle , Masculino , Adesão à Medicação/estatística & dados numéricos , Pessoa de Meia-Idade , Osteoporose/complicações , Osteoporose/fisiopatologia , Preferência do Paciente , Estudos Prospectivos , Resultado do Tratamento
5.
Acta Neurol Scand ; 128(3): 160-5, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23410225

RESUMO

OBJECTIVES: To explore the possibility of a generally applicable tool for the immediate diagnosis of Parkinson's disease (PD) in its early stage, we compared the sensitivity and specificity of an acute levodopa challenge test with that of (123) I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy. MATERIALS AND METHODS: A consecutive series of 45 patients with extrapyramidal symptoms were recruited to the acute levodopa challenge and evaluated for improvement by use of the Unified Parkinson's Disease Rating Scale motor scores. Of these patients, 32 of them were also examined by MIBG scintigraphy. The patients were followed up for at least 24 months, and 22 patients were diagnosed as having clinically definite PD. RESULTS: The sensitivity and specificity of the acute levodopa challenge test to predict clinical diagnosis of PD were 81.8% and 81.8%, respectively, which were better than those obtained by MIBG scintigraphy (62.5% and 62.5%). In both early- and middle-stages of PD, the test gave better sensitivity than MIBG scintigraphy. CONCLUSIONS: Considering that the well-established and frequently referred clinical diagnostic criteria require longitudinal observation for at least 24 months, the acute levodopa challenge test can be used as an immediate diagnostic tool for PD with sensitivity and specificity comparable to those of MIBG.


Assuntos
3-Iodobenzilguanidina , Antiparkinsonianos/uso terapêutico , Levodopa/uso terapêutico , Doença de Parkinson/diagnóstico , Doença de Parkinson/tratamento farmacológico , Compostos Radiofarmacêuticos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Sensibilidade e Especificidade , Fatores de Tempo
6.
Phys Rev Lett ; 108(26): 262501, 2012 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-23004969

RESUMO

A high-resolution measurement of inelastic proton scattering off (90)Zr near 0° was performed at 295 MeV with a focus on a pronounced strength previously reported in the low-energy tail of giant dipole resonance. A forest of fine structure was observed in the excitation energy region 7-12 MeV. A multipole decomposition analysis of the angular distribution for the forest was carried out using the ECIS95 distorted-wave Born approximation code with the Hartree-Fock plus random-phase approximation model of E1 and M1 transition densities and inclusion of E1 Coulomb excitation. The analysis separated pygmy dipole and M1 resonances in the forest at E(PDR)=9.15±0.18 MeV with Γ(PDR)=2.91±0.64 MeV and at E(M1)=9.53±0.06 MeV with Γ(M1)=2.70±0.17 MeV in the Lorentzian function, respectively. The B(E1)↑ value for pygmy dipole resonance over 7-11 MeV is 0.75±0.08 e(2)fm(2), which corresponds to 2.1±0.2% of the Thomas-Reiche-Kuhn sum rule.

7.
Diabetologia ; 54(10): 2649-59, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21786155

RESUMO

AIMS/HYPOTHESIS: Several lines of evidence suggest that incretin-based therapies suppress the development of cardiovascular disease in type 2 diabetes. We investigated the possibility that glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) can prevent the development of atherosclerosis in Apoe (-/-) mice. METHODS: Apoe (-/-) mice (17 weeks old) were administered GLP-1(7-36)amide, GLP-1(9-36)amide, GIP(1-42) or GIP(3-42) for 4 weeks. Aortic atherosclerosis, oxidised LDL-induced foam cell formation and related gene expression in exudate peritoneal macrophages were determined. RESULTS: Administration of GLP-1(7-36)amide or GIP(1-42) significantly suppressed atherosclerotic lesions and macrophage infiltration in the aortic wall, compared with vehicle controls. These effects were cancelled by co-infusion with specific antagonists for GLP-1 and GIP receptors, namely exendin(9-39) or Pro(3)(GIP). The anti-atherosclerotic effects of GLP-1(7-36)amide and GIP(1-42) were associated with significant decreases in foam cell formation and downregulation of CD36 and acyl-coenzyme A:cholesterol acyltransferase-1 (ACAT-1) in macrophages. GLP-1 and GIP receptors were both detected in Apoe (-/-) mouse macrophages. Ex vivo incubation of macrophages with GLP-1(7-36)amide or GIP(1-42) for 48 h significantly suppressed foam cell formation. This effect was wholly abolished in macrophages pretreated with exendin(9-39) or (Pro(3))GIP, or with an adenylate cyclase inhibitor, MDL12,330A, and was mimicked by incubation with an adenylate cyclase activator, forskolin. The inactive forms, GLP-1(9-36)amide and GIP(3-42), had no effects on atherosclerosis and macrophage foam cell formation. CONCLUSIONS/INTERPRETATION: Our study is the first to demonstrate that active forms of GLP-1 and GIP exert anti-atherogenic effects by suppressing macrophage foam cell formation via their own receptors, followed by cAMP activation. Molecular mechanisms underlying these effects are associated with the downregulation of CD36 and ACAT-1 by incretins.


Assuntos
Apolipoproteínas E/metabolismo , Aterosclerose/tratamento farmacológico , Incretinas/farmacologia , Acetil-CoA C-Acetiltransferase/metabolismo , Animais , Apolipoproteínas E/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Western Blotting , Antígenos CD36/metabolismo , Linhagem Celular , Células Cultivadas , Células Espumosas/citologia , Células Espumosas/efeitos dos fármacos , Polipeptídeo Inibidor Gástrico/farmacologia , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Humanos , Masculino , Camundongos , Camundongos Knockout , Microscopia Confocal , Fragmentos de Peptídeos/farmacologia , Peptídeos/farmacologia , Reação em Cadeia da Polimerase em Tempo Real
8.
J Exp Med ; 171(4): 1027-41, 1990 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-1969918

RESUMO

The cutaneous graft-versus-host disease (GVHD) lesions induced by intradermal injection of cloned autoreactive T cells have been shown to subside rapidly and the epidermis returns to normal 2 wk after injection. Those mice that had spontaneously recovered from the cutaneous GVHD became resistant to subsequent attempts to induce the cutaneous GVHD by the T cells while maintaining their activity to mount delayed-type hypersensitivity (DTH) responses and to induce the enlargement of the popliteal lymph nodes (PLN). The resistance appeared to be restricted to the epidermal structures of the injection sites, suggesting the involvement of locally acting suppression mechanisms. This local resistance was not specific for the clonotype used for the induction of the resistance. A loss of the epidermal integrity by an attack of T cells capable of producing cutaneous GVHD was a prerequisite for the induction of the resistance. By up to at least 8 mo after injection of the T cells, no mice became susceptible to the cutaneous GVHD again, provided that the T cells were injected into the same footpad sites that had initially received the T cells. This resistance correlated well with the great increase (20-30-fold) in Thy-1+ EC number. The great increase in the number of Thy-1+ EC following destruction of epidermal structures may be important in protecting the epidermal integrity from an additional attack by T cells.


Assuntos
Antígenos de Superfície/imunologia , Doença Enxerto-Hospedeiro , Hipersensibilidade Tardia , Pele/imunologia , Linfócitos T/imunologia , Animais , Anticorpos Monoclonais , Antígenos de Superfície/análise , Linhagem Celular , Células Clonais , Epiderme/imunologia , Feminino , Imunofluorescência , Imunidade Celular , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T/transplante , Antígenos Thy-1
10.
J Thromb Haemost ; 6(1): 139-46, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17988229

RESUMO

BACKGROUND: Thrombin-activatable fibrinolysis inhibitor (TAFI) has been reported to affect wound healing and fibrotic processes, but its role in renal tubulointerstitial fibrosis remains unknown. OBJECTIVE: To study its potential role, we compared TAFI-deficient and wild-type mice for the degree of renal fibrosis caused by unilateral ureteral obstruction (UUO). METHODS: The grade of tubulointerstitial fibrosis, the activity of plasmin, MMP-2 and MMP-9 were evaluated on days 4 and 9 after UUO. RESULTS: The renal content of hydroxyproline and the activity of plasmin, MMP-2 and MMP-9 were significantly increased in kidneys with UUO from TAFI-deficient mice compared with those from wild-type mice. These differences disappeared when animals with UUO from both groups were treated with the plasmin inhibitor tranexamic acid. The renal concentrations of fibrogenic cytokines were also significantly elevated in kidneys with UUO from TAFI-deficient mice compared with those from wild-type mice. CONCLUSION: The results of this study suggest that increased renal activity of plasmin in TAFI-deficient mice causes increased renal interstitial fibrosis in obstructive nephropathy.


Assuntos
Carboxipeptidase B2/fisiologia , Fibrinolisina/análise , Fibrose/etiologia , Nefropatias/etiologia , Obstrução Ureteral/complicações , Animais , Carboxipeptidase B2/deficiência , Citocinas/análise , Hidroxiprolina/análise , Nefropatias/patologia , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 9 da Matriz/análise , Camundongos , Camundongos Knockout
12.
Clin Exp Rheumatol ; 24(3): 260-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16870092

RESUMO

OBJECTIVE: To evaluate the effectiveness of disease-modifying antirheumatic drugs, namely, methotrexate (MTX), sulfasalazine (SSZ) and bucillamine (BUC) at low-doses (4, 6 or 8 mg MTX, 500 or 1,000 mg SSZ, and 100 or 200 mg BUC) in 1,358 patients with a follow-up of at least 12 months and more than 120 months. METHODS: Clinical assessments were based on the number of painful joints (NPJ) and that of swollen joints (NSJ), CRP level, erythrocyte sedimentation rate, rheumatoid factor level and morning stiffness before and after treatment. Results were evaluated on the basis of the duration of treatment for each drug with inefficacy or inadequate efficacy as one endpoint for discontinuation and adverse drug reactions (ADRs) as the other in single agent and combination therapy. The incidence and nature of ADRs in single and combination treatment are described. RESULTS: The effects of MTX, SSZ and BUC on clinical parameters were monitored over the first three months, and in particular, NPJs and NSJs were found to decrease significantly during single agent MTX or BUC treatment over 108 months. CRP levels remained significantly improved for more than 120 months with MTX. In the single and combination long-term treatments, continuation rate with inefficacy or inadequate efficacy as the end point achieved for each of the treatments were 83.1% for MTX, 76.0% for BUC, 68.5% for SSZ, and in the case of the combination treatments, these rates were 83.3% for MTX + BUC and 71.0% for MTX+SSZ. Continuation rates using ADRs as the end point were 88% for SSZ, 79.6% for BUC and 79.4% for MTX. The incidences of ADRs for the various treatments were: MTX 22.2%, SSZ 11.0%, BUC 20.6%, MTX + BUC 30.0% and MTX + SSZ 31.2%. CONCLUSION: MTX showed the highest efficacy even though it was administrated at a low dose (6-8 mg), as a single agent or in combination with other treatment. However, in combination treatments, the continuous duration of treatment ending in ADRs as the end point were lower than those in single treatments with MTX, SSZ and BUC.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Cisteína/análogos & derivados , Metotrexato/uso terapêutico , Sulfassalazina/uso terapêutico , Artrite Reumatoide/fisiopatologia , Cisteína/uso terapêutico , Relação Dose-Resposta a Droga , Esquema de Medicação , Quimioterapia Combinada , Feminino , Humanos , Articulações/efeitos dos fármacos , Articulações/patologia , Articulações/fisiopatologia , Masculino , Pessoa de Meia-Idade , Dor/tratamento farmacológico , Dor/patologia , Dor/fisiopatologia , Prednisolona/uso terapêutico , Resultado do Tratamento
13.
Cancer Res ; 54(12): 3171-2, 1994 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-8205535

RESUMO

8-Hydroxydeoxyguanosine (oh8dG) is a promutagenic DNA lesion produced by oxygen radicals. We examined alterations in the oh8dG level in human livers which have chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. The oh8dG content in livers with chronic hepatitis was significantly higher than the oh8dG content in normal livers (P < 0.05). There was also a significant correlation between the oh8dG content in noncancerous liver tissues with individual serum alanine aminotransferase concentration (r = 0.515; P < 0.001). Thus, chronic inflammation in the liver produces oxidative DNA damage, which may increase the risk for genomic alterations causing hepatocarcinogenesis.


Assuntos
Dano ao DNA , DNA/metabolismo , Guanosina/análogos & derivados , Hepatite/metabolismo , Fígado/metabolismo , Alanina Transaminase/sangue , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/metabolismo , Doença Crônica , Estudos de Avaliação como Assunto , Guanosina/metabolismo , Hepatite/complicações , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/metabolismo , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/metabolismo , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Fatores de Risco
14.
Cancer Res ; 57(8): 1435-7, 1997 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9108441

RESUMO

Allelic deletion of multiple regions on the short arm of chromosome 3 (3p) implies the presence of multiple important tumor suppressor genes in human carcinogenesis. The FHIT gene, identified recently in chromosome 3p14.2, shows frequent allelic deletion and aberrant transcripts in gastrointestinal tumors. After determining the intron sequences flanking each of the coding exons of the FHIT gene and designing intron primers to facilitate mutation analysis of genomic DNA samples, we analyzed the complete coding sequences in matched cancer and normal tissues from 40 cases with primary gastric cancer using intron primers, PCR-single-strand conformation polymorphism analysis, and direct sequencing. A somatic missense mutation in exon 6, codon 61, ACG (threonine) --> ATG (methionine) was found in a signet ring cell adenocarcinoma. We also evaluated allelic deletion in these tumors by PCR-based microsatellite analysis; allelic deletion occurred in 42.1% (16 of 38) of evaluable cases. This is the first report of a somatic missense mutation of the FHIT gene in a primary tumor. Presence of a point mutation and frequent allelic deletions are consistent with the hypothesis that FHIT gene alterations are involved in the development of primary gastric cancers.


Assuntos
Hidrolases Anidrido Ácido , Éxons/genética , Deleção de Genes , Genes Supressores de Tumor/genética , Proteínas de Neoplasias/genética , Fases de Leitura Aberta/genética , Proteínas/genética , Neoplasias Gástricas/genética , Sequência de Bases , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples
15.
Cancer Res ; 59(4): 843-8, 1999 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10029073

RESUMO

The tumor suppressor protein p53 contributes to the control of cell cycle checkpoints and stress-induced apoptosis and is frequently mutated in many different types of human cancers. The COOH terminus of p53 modulates the transcriptional and apoptotic activities of the protein. Although COOH-terminal mutants of p53 are uncommon, we proposed that these p53 mutants nevertheless contributed to the selective clonal expansion of the cancer cells. Therefore, we analyzed the tumor-derived p53 COOH-terminal domain (CTD) mutants (352D/H, 356G/W, 342-stop, 360-del, and 387-del) functionally. The results have revealed that all mutants have impaired apoptotic activity when compared with wild-type p53. However, some of these mutants still transcriptionally transactivate p21Waf/Cip1 and inhibit cell growth. Interestingly, of the tumor-derived CTD mutants, oligomerization-defective mutant 342-stop was the only one that did not exhibit sequence-specific DNA binding or failed to transactivate p21Waf1/Cip1, Bax, and IGF-BP3 transcriptionally. The failure to inhibit cell growth by this tumor-derived CTD mutant supports the hypothesis that p53 sequence-specific transcriptional transactivity to p21Waf1/Cip1 is correlated with induction of cell cycle arrest and that the p53 transcriptional transactivity requires oligomerization of the p53 protein. These and other data indicate that the CTD of p53 is an important component of p53-mediated apoptosis and cell growth arrest and that inactivation of the apoptotic function, but not the inhibition of growth, is an important step during human tumorigenesis.


Assuntos
Apoptose , Ativação Transcricional , Proteína Supressora de Tumor p53/fisiologia , Divisão Celular , Células Cultivadas , DNA/metabolismo , Humanos , Mutação , Relação Estrutura-Atividade , Proteína Supressora de Tumor p53/química
16.
Cancer Res ; 60(13): 3333-7, 2000 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10910033

RESUMO

Ulcerative colitis (UC) is a chronic inflammatory disease that produces reactive oxygen and nitrogen species and increases the risk of colorectal cancer (CRC). The p53 tumor suppressor gene is frequently mutated in UC-associated dysplastic lesions and CRC. We are exploring the hypothesis that p53 mutations in the nontumorous colonic tissue in noncancerous UC cases indicate genetic damage from exposure to exogenous and endogenous carcinogens and may identify individuals at increased cancer risk. We are reporting, for the first time, the frequency of specific p53 mutated alleles in nontumorous colon tissue from donors either with or without UC by using a highly sensitive genotypic mutation assay. Higher p53 mutation frequencies of both G:C to A:T transitions at the CpG site of codon 248 and C:G to T:A transitions at codon 247 were observed in colon from UC cases when compared with normal adult controls (P = 0.001 and P = 0.001, respectively). In the UC cases, higher p53 codon 247 and 248 mutation frequencies were observed in the inflamed lesional regions when compared with the nonlesional regions of their colon (P < 0.001 and P = 0.001). The colonic nitric oxide synthase-2 activity was higher in UC cases than in non-UC adult controls (P = 0.02). Our data are consistent with the hypothesis that a higher frequency of p53 mutant cells can be generated under oxidative stress in people with UC. The increased frequency of specific p53 mutated alleles in noncancerous UC colon tissue may confer susceptibility to the development of CRC in an inflammatory microenvironment.


Assuntos
Colite Ulcerativa/genética , Neoplasias do Colo/genética , Genes p53 , Mutação Puntual , Adulto , Códon , Colite Ulcerativa/complicações , Colite Ulcerativa/patologia , Colo/patologia , Neoplasias do Colo/etiologia , Fosfatos de Dinucleosídeos/genética , Predisposição Genética para Doença , Genótipo , Humanos , Mucosa Intestinal/patologia , Óxido Nítrico Sintase/análise , Óxido Nítrico Sintase Tipo II , Valores de Referência
17.
Kyobu Geka ; 59(7): 573-6, 2006 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-16856533

RESUMO

A 3-year-old boy suffered from the poor body weight gain under the diagnosis of partial anomalous pulmonary venous connection (PAPVC) to the high portion of the superior vena cava (SVC) associated with ventricular septal defect (VSD) and intact atrial septum (IAS). Preoperative cardiac catheterization revealed the pulmonary to systemic flow ratio 2.6 and mean pulmonary arterial pressure of 21 mmHg. He successfully underwent surgical repair with Williams method using right atrial (RA) flap out and VSD patch closure. Postoperative course was uneventful and echocardiography demonstrated no obstruction at the both routes of neo-SVC and neo-right upper pulmonary venous return.


Assuntos
Comunicação Interventricular/cirurgia , Veias Pulmonares/anormalidades , Retalhos Cirúrgicos , Procedimentos Cirúrgicos Vasculares/métodos , Veia Cava Superior/anormalidades , Pré-Escolar , Átrios do Coração , Comunicação Interventricular/complicações , Humanos , Masculino , Veias Pulmonares/cirurgia , Veia Cava Superior/cirurgia
18.
Oncogene ; 14(10): 1255-8, 1997 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-9121777

RESUMO

Mutations in the transforming growth factor beta type II receptor (TGFbeta RII) gene have been detected in several human cancers exhibiting microsatellite instability. To extend analyses of this gene, we previously investigated the exon-intron organization of the TGFbeta RII gene and defined seven exons and flanking intron sequences. In this study, we further determined the nucleotide sequences surrounding these seven exons and designed eight sets of intron-based primers to examine the entire coding region of the TGFbeta RII gene. Using these primers, we screened genomic DNA sequences from 30 sporadic colorectal cancers for mutations of the TGFbeta RII gene. TGFbeta RII mutations were detected in two of 30 tumors and both displayed microsatellite instability. One had a deletion in a polyadenine tract in exon 3 and the other had a point mutation in the kinase domain located in exon 7. There were no mutations in exons 1, 2, 4, 5 and 6. These results further implicate the polyadenine tract and kinase domain as mutational hotspots in the TGFbeta RII gene in cells with genomic instability and suggest that TGFbeta RII gene mutations occur rarely in cells lacking genomic instability.


Assuntos
Neoplasias do Colo/genética , Neoplasias do Colo/ultraestrutura , Primers do DNA , DNA de Neoplasias/genética , Íntrons , Receptores de Fatores de Crescimento Transformadores beta/genética , Sequência de Bases , Análise Mutacional de DNA , Regulação Neoplásica da Expressão Gênica , Humanos , Dados de Sequência Molecular , Proteínas Serina-Treonina Quinases , Receptor do Fator de Crescimento Transformador beta Tipo II
19.
Oncogene ; 15(1): 117-22, 1997 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-9233784

RESUMO

The transforming growth factor-beta (TGF-beta) binds the type II TGF-beta growth factor receptor (RII) to inhibit the growth of most epithelial tissues. Most human colon and gastric cancers with microsatellite instability (MI) have frameshift mutations in polynucleotide repeats within the RII coding region; these mutations truncate the receptor protein and disable the serine/threonine kinase to produce TGF-beta resistance. To further investigate the type, frequency and tissue distribution of RII mutations, we selected 24 human cancer cell lines from various tissues which were previously reported to be resistant to the inhibitory effects of TGF-beta. We developed protocols for non-isotopic SSCP analysis of PCR products from genomic DNA samples, and we tested them for microsatellite instability. PCR-SSCP analysis followed by DNA sequencing identified deletion mutations in the exon 3 poly-adenine tract in three colon tumor cell lines: LS174T and SW48 had a single base deletion and LS411 had a two base deletion. Among the 24 previously unreported cell lines, only these three demonstrated microsatellite instability. These and other recent data indicate that RII mutations are essentially confined to colon and gastric cancers with microsatellite instability. The narrow spectrum of tissues containing RII mutations illustrates the complexity of genetic checkpoints in human carcinogenesis.


Assuntos
Mutação , Receptores de Fatores de Crescimento Transformadores beta/genética , Fator de Crescimento Transformador beta/farmacologia , Divisão Celular/efeitos dos fármacos , Neoplasias do Colo/genética , Análise Mutacional de DNA , Humanos , Repetições de Microssatélites , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Proteínas Serina-Treonina Quinases , Receptor do Fator de Crescimento Transformador beta Tipo II , Neoplasias Gástricas/genética , Células Tumorais Cultivadas
20.
Oncogene ; 18(22): 3415-21, 1999 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-10362363

RESUMO

p73 is a candidate tumor suppressor gene with substantial DNA and protein homology to the p53 tumor suppressor gene. We have investigated two hypotheses: (a) p73 is mutated in diverse types of human cancer, and (b) p73 is functionally redundant with p53 in carcinogenesis so that mutations would be exclusive in these two genes. The entire coding region and intronic splice junctions of p73 were examined in 54 cancer cell lines. Three lung cancer cell lines contained mutations that affected the amino acid sequence. One amino acid substitution was in a region with homology to the specific DNA binding region of p53 and two microdeletions were outside the region of homology. Two of the cell lines with p73 mutations also carried p53 mutations. Although our results are inconsistent with the two hypotheses tested, p73 mutations may contribute infrequently to the molecular pathogenesis of human lung cancer.


Assuntos
Proteínas de Ligação a DNA/genética , Genes Supressores de Tumor , Mutação , Neoplasias/genética , Proteínas Nucleares/genética , Proteína Supressora de Tumor p53/genética , Análise Mutacional de DNA , Humanos , Íntrons , Neoplasias Pulmonares/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Análise de Sequência de DNA , Células Tumorais Cultivadas , Proteína Tumoral p73 , Proteínas Supressoras de Tumor
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