RESUMO
Transverse single-spin asymmetries of very forward neutral pions generated in polarized p+p collisions allow us to understand the production mechanism in terms of perturbative and nonperturbative strong interactions. During 2017, the RHICf Collaboration installed an electromagnetic calorimeter in the zero-degree region of the STAR detector at the Relativistic Heavy Ion Collider (RHIC) and measured neutral pions produced at pseudorapidity larger than 6 in polarized p+p collisions at sqrt[s]=510 GeV. The large nonzero asymmetries increasing both in longitudinal momentum fraction x_{F} and transverse momentum p_{T} have been observed at low transverse momentum p_{T}<1 GeV/c for the first time, at this collision energy. The asymmetries show an approximate x_{F} scaling in the p_{T} region where nonperturbative processes are expected to dominate. A non-negligible contribution from soft processes may be necessary to explain the nonzero neutral pion asymmetries.
RESUMO
This study investigated rare variants associated with atopic dermatitis. We performed exome analyses on 37 patients who were diagnosed with atopic dermatitis by board-certified dermatologists and had total serum IgE levels greater than 1000 IU/ml. The exome analysis identified seven variants with <1% allele frequency in Asian (ASN) population of 1000 Genomes Project phase 1 data and >5% allele frequency in the atopic dermatitis exome samples. We then conducted a replication study using 469 atopic dermatitis patients with total serum IgE ≥1000 IU/ml and 935 Japanese controls to assess the presence of these 7 candidate variants. The replication study confirmed that CYP27A1 rs199691576 (A/G) was associated with atopic dermatitis with high serum IgE levels (P = 0.012, odds ratio = 2.1). CYP27A1 is involved in the metabolism of vitamin D3, which plays important roles in modulating immune function. Previous studies have reported polymorphisms in vitamin D pathway genes that are associated with allergy-related phenotypes. Our data confirm the importance of genes regulating the vitamin D pathway in the development of atopic dermatitis.
Assuntos
Colestanotriol 26-Mono-Oxigenase/genética , Dermatite Atópica/sangue , Dermatite Atópica/genética , Predisposição Genética para Doença , Variação Genética , Imunoglobulina E/sangue , Adulto , Alelos , Dermatite Atópica/imunologia , Feminino , Frequência do Gene , Genótipo , Humanos , Imunoglobulina E/imunologia , Masculino , Mutação de Sentido Incorreto , Razão de Chances , Polimorfismo de Nucleotídeo Único , Adulto JovemRESUMO
AIMS/HYPOTHESIS: Incretins stimulate insulin secretion in a glucose-dependent manner but also promote pancreatic beta cell protection. Dipeptidyl peptidase-4 (DPP-4) inhibitors are a new glucose-lowering treatment that blocks incretin degradation by DPP-4. We assessed whether DPP-4 inhibition suppresses the progression to hyperglycaemia in a low-dose streptozotocin (STZ)-induced diabetic mouse model, and then investigated how DPP-4 inhibition affects islet function and morphology. METHODS: The DPP-4 inhibitor, des-fluoro-sitagliptin (SITA), was administered to mice during and after STZ injections, and in some mice also before STZ. RESULTS: In control mice, STZ resulted in hyperglycaemia associated with impaired insulin secretion and excess glucagon secretion. In SITA-treated STZ mice, these metabolic abnormalities were improved, particularly when SITA administration was initiated before STZ injections. We observed beta cell loss and dramatic alpha cell expansion associated with decreased insulin content and increased glucagon content after STZ administration. In SITA-treated mice, islet architecture and insulin content were preserved, and no significant increase in glucagon content was observed. After STZ exposure, beta cell apoptosis increased before hyperglycaemia, and SITA treatment reduced the number of apoptotic beta cells. Interestingly, alpha cell proliferation was observed in non-treated mice after STZ injection, but the proliferation was not observed in SITA-treated mice. CONCLUSIONS/INTERPRETATION: Our results suggest that the ability of DPP-4 inhibition to suppress the progression to STZ-induced hyperglycaemia involves both alleviation of beta cell death and alpha cell proliferation.
Assuntos
Inibidores da Dipeptidil Peptidase IV/metabolismo , Células Secretoras de Glucagon/citologia , Células Secretoras de Insulina/citologia , Estreptozocina/farmacologia , Animais , Glicemia/metabolismo , Proliferação de Células , Progressão da Doença , Teste de Tolerância a Glucose , Hemoglobinas/metabolismo , Imuno-Histoquímica/métodos , Incretinas/metabolismo , Insulina/metabolismo , Secreção de Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
A novel subset of T cells characterized by the expression of an invariant T cell antigen receptor (TCR) encoded by V alpha 24J alpha Q gene segments was investigated in patients with systemic sclerosis (SSc). Polymerase chain reaction analysis demonstrated that the V alpha 24 TCR repertoire was selectively used in CD4-CD8- double-negative T cells both in patients and in healthy individuals, while almost all families of TCR V alpha were expressed in single-positive T cell fractions. The V alpha 24+ double-negative T cells were increased by approximately fivefold in patients. However, sequence analysis clearly showed significant differences in the V alpha 24 TCR repertoire dominating in patients and healthy donors. In healthy individuals, the invariant V alpha 24J alpha Q was expanded and comprised 20-50% of the total TCR-alpha, while their selective reduction was observed in SSc patients who also showed expansion of invariant V alpha 24 TCR other than V alpha 24J alpha Q. Analogous to murine invariant V alpha 14J alpha 281 TCR, these results suggest that T cells with invariant V alpha 24J alpha Q TCR would function as regulatory T cells, whereas T cells bearing other invariant V alpha 24 TCR in SSc patients could be autoaggressive T cells in nature.
Assuntos
Doenças Autoimunes/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Escleroderma Sistêmico/imunologia , Subpopulações de Linfócitos T/imunologia , Povo Asiático , Sequência de Bases , Antígenos CD4/análise , Antígenos CD8/análise , Separação Celular , Clonagem Molecular , Citometria de Fluxo , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Seleção Genética , Análise de Sequência de DNARESUMO
It is known that rearrangement of the T cell antigen receptor (TCR) gene occurs in the thymus during T cell development and consequently results both in the deletion of DNA between the variable (V) and diversity/joining segments and in the formation of a circular DNA with recombination signal sequences. Here, we provide evidence that V alpha 14+ TCR gene rearrangements take place in extrathymic sites, such as bone marrow, liver, and intestine, but not in spleen, because we were able to detect frequent productive and nonproductive V alpha 14+ coding and signal sequences as a result of TCR rearrangements in extrathymic sites. Similar findings were also detected in athymic mice. Quantitative analysis shows that the relative amounts of V alpha 14 gene-mediated signal sequences in extrathymic tissues are higher than those in thymus. On the contrary, TCR rearrangements of V alpha 1.1 T cells, which are known to develop in the thymus, were mainly detected in the thymus, Peyer's patch, and spleen, but not in other extrathymic tissues, showing patterns distinct from V alpha 14 TCR rearrangements. These findings are evidence of extrathymic development of V alpha 14+ T cells. Differential characteristic TCR rearrangement patterns also indicate that distinct TCR repertoires are generated in different lymphoid tissues.
Assuntos
Proteínas de Ligação a DNA , Rearranjo Gênico da Cadeia alfa dos Receptores de Antígenos dos Linfócitos T , Proteínas de Homeodomínio , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Linfócitos T/citologia , Timo/citologia , Animais , Sequência de Bases , Medula Óssea/imunologia , Células da Medula Óssea , DNA , Fígado/citologia , Fígado/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Sinais Direcionadores de Proteínas/genética , Proteínas/genética , Baço/citologia , Baço/imunologia , Linfócitos T/imunologia , Timo/imunologiaRESUMO
Pregnancy with amyotrophic lateral sclerosis (ALS) is rare and generally considered dangerous. Riluzole is the only drug approved for use in ALS, but the effect on maternal and fetal health is unknown. We describe the case of an ALS patient taking riluzole throughout pregnancy. A 34-year old Japanese woman, who had been diagnosed with probable ALS 4 years earlier, visited our hospital for abdominal distension, without knowing that she was pregnant. The patient had been taking riluzole for 2 years, inclusive of her gestational months, and we decided to continue administration of the medication. The patient delivered a normal female infant transvaginally at 38 weeks gestation. The patient's neurological status was stable 1 year after delivery and the baby had developed normally. We found that, in this case, riluzole did not cause any side-effects to the pregnant woman or her fetus.
Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Complicações na Gravidez/tratamento farmacológico , Riluzol/uso terapêutico , Adulto , Feminino , Monitorização Fetal , Humanos , Recém-Nascido , Gravidez , Resultado da Gravidez , Resultado do TratamentoRESUMO
BACKGROUND: Isoprostanes are prostaglandin (PG)-like compounds synthesized by oxidative stress, not by cyclooxygenase, and increase in bronchoalveolar lavage fluid of patients with asthma. The airway inflammation implicated in this disease may be amplified by oxidants. Although isoprostanes are useful biomarkers for oxidative stress, the action of these agents on airways has not been fully elucidated. OBJECTIVE: This study was designed to determine the intracellular mechanisms underlying the effects of oxidative stress on airway smooth muscle, focused on Ca(2+) signalling pathways involved in the effect of 8-iso-PGF(2 alpha). METHODS: Using simultaneous recording of isometric tension and F(340)/F(380) (an indicator of intracellular concentrations of Ca(2+), [Ca(2+)]i, we examined the correlation between tension and [Ca(2+)]i in response to 8-iso-PGF(2 alpha) in the fura-2 loaded tracheal smooth muscle. RESULTS: Augmented tension and F(340)/F(380) by 8-iso-PGF(2 alpha) were attenuated by ICI-192605, an antagonist of thromboxane A(2) receptors (TP receptors). Moreover, D609, an antagonist of phosphatidylcholine-specific phospholipase C, markedly reduced both the tension and F(340)/F(380) induced by 8-iso-PGF(2 alpha), whereas U73122, an antagonist of phosphatidylinositol-specific phospholipase C, modestly inhibited them by 8-iso-PGF(2 alpha). SKF96365, a non-selective antagonist of Ca(2+) channels, markedly reduced both tension and F(340)/F(380) by 8-iso-PGF(2 alpha). However, diltiazem and verapamil, voltage-dependent Ca(2+) channel inhibitors, modestly attenuated tension although their reduction of F(340)/F(380) was not different from that by SKF96365. Y-27632, an inhibitor of Rho-kinase, significantly attenuated contraction induced by 8-iso-PGF(2 alpha) without reducing F(340)/F(380), whereas GF109203X and Go6983, protein kinase C inhibitors, did not markedly antagonize them although reducing F(340)/F(380) with a potency similar to Y-27632. CONCLUSION: 8-iso-PGF(2 alpha) causes airway smooth muscle contraction via activation of TP receptors. Ca(2+) mobilization by SKF96365- and D609-sensitive Ca(2+) influx and Ca(2+) sensitization by Rho-kinase contribute to the intracellular mechanisms underlying the action of 8-iso-PGF(2 alpha). Rho-kinase may be a therapeutic target for the physiologic abnormalities induced by oxidative stress in airways.
Assuntos
Sinalização do Cálcio/fisiologia , Dinoprosta/análogos & derivados , Músculo Liso/efeitos dos fármacos , Traqueia/efeitos dos fármacos , Traqueia/fisiologia , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Amidas/farmacologia , Animais , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Diltiazem/farmacologia , Dinoprosta/farmacologia , Dioxanos/farmacologia , Inibidores Enzimáticos/farmacologia , Estrenos/farmacologia , Cobaias , Imidazóis/farmacologia , Técnicas In Vitro , Indóis/farmacologia , Masculino , Maleimidas/farmacologia , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Liso/fisiologia , Norbornanos , Piridinas/farmacologia , Pirrolidinonas/farmacologia , Receptores de Tromboxano A2 e Prostaglandina H2/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Tiocarbamatos , Tionas/farmacologia , Fosfolipases Tipo C/antagonistas & inibidores , Vasoconstritores/farmacologia , Verapamil/farmacologia , Quinases Associadas a rho/antagonistas & inibidoresRESUMO
BACKGROUND: Recent studies have revealed that in asthma, mast cells infiltrate to the smooth muscle layer and release tryptase, an enzymatic activator of protease-activated receptor 2 (PAR2). This phenomenon, mast cell myositis, is proposed as a new feature of asthma. However, little is known about the involvement of mast cell myositis in the pathophysiology of asthma. OBJECTIVE: This study was designed to determine whether mast cell degranulation has any functional impact on beta-adrenoceptors via PAR2 in airway smooth muscle. Moreover, we focused on Ca(2+) signalling as a mechanism underlying alteration of smooth muscle tone and responsiveness. METHODS: Isometric tension and F(340)/F(380), an indicator of the concentration of intracellular Ca(2+) ([Ca(2+)](i)), were simultaneously measured using fura-2-loaded tissues isolated from guinea-pig tracheal smooth muscle. RESULTS: Tryptase (1-100 nm) caused tension with elevated F(340)/F(380), and after exposure to tryptase for 15 min the inhibitory effect of isoprenaline (ISO) against methacholine was attenuated without elevating F(340)/F(380) in a concentration-dependent manner. Tryptase (<1 nm) had a modest effect on tension, but prolonged treatment (=120 min) with 0.1 nm tryptase also reduced the effects of ISO in a time-dependent manner. When tissues were incubated with tryptase in the presence of Y-27632, a Rho-kinase inhibitor, reduced responsiveness to ISO by tryptase was reversed without affecting F(340)/F(380). In contrast, pre-treatment with SKF96365, a non-selective inhibitor of Ca(2+) channels, did not antagonize the effect of tryptase. Moreover, pre-treatment with SLIGKV-NH(2), a non-enzymatic activator of PAR2, resulted in a loss of beta-adrenergic efficacy, similar to tryptase. The effect of cAMP-related agents bypassing beta-adrenoceptors was not attenuated after exposure to tryptase. CONCLUSION: In mast cell myositis, tryptase released from mast cells acts on airway smooth muscle, leading to homologous beta-adrenergic desensitization mediated by [Ca(2+)](i)-independent mechanisms via PAR2 activation.
Assuntos
Cálcio/metabolismo , Mastócitos/enzimologia , Músculo Liso/metabolismo , Receptores Adrenérgicos beta/metabolismo , Traqueia/metabolismo , Triptases/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Animais , Sinalização do Cálcio/efeitos dos fármacos , Cobaias , Humanos , Masculino , Mastócitos/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Receptor PAR-2/metabolismo , Traqueia/efeitos dos fármacos , Quinases Associadas a rho/metabolismoRESUMO
Signaling adaptor protein Crk regulates cell motility and growth through its targets Dock180 and C3G, those are the guanine-nucleotide exchange factors (GEFs) for small GTPases Rac and Rap, respectively. Recently, overexpression of Crk has been reported in various human cancers. To define the role for Crk in human cancer cells, Crk expression was targeted in the human ovarian cancer cell line MCAS through RNA interference, resulting in the establishment of three Crk knockdown cell lines. These cell lines exhibited disorganized actin fibers, reduced number of focal adhesions, and abolishment of lamellipodia formation. Decreased Rac activity was demonstrated by pull-down assay and FRET-based time-lapse microscopy, in association with suppression of both motility and invasion by phagokinetic track assay and transwell assay in these cells. Furthermore, Crk knockdown cells exhibited slow growth rates in culture and suppressed anchorage-dependent growth in soft agar. Tumor forming potential in nude mice was attenuated, and intraperitoneal dissemination was not observed when Crk knockdown cells were injected into the peritoneal cavity. These results suggest that the Crk is a key component of focal adhesion and involved in cell growth, invasion, and dissemination of human ovarian cancer cell line MCAS.
Assuntos
Invasividade Neoplásica , Neoplasias Ovarianas/metabolismo , Proteínas Proto-Oncogênicas c-crk/metabolismo , Citoesqueleto de Actina/patologia , Animais , Adesão Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Imunofluorescência , Humanos , Immunoblotting , Camundongos , Camundongos Nus , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neoplasias Ovarianas/patologia , Pseudópodes/patologia , Interferência de RNA , Proteínas rac de Ligação ao GTP/metabolismoRESUMO
Adaptation to stress evokes a variety of biological responses, including activation of the hypothalamic-pituitary-adrenal (HPA) axis and synthesis of a panel of stress-response proteins at cellular levels: for example, expression of thioredoxin (TRX) is significantly induced under oxidative conditions. Glucocorticoids, as a peripheral effector of the HPA axis, exert their actions via interaction with a ligand-inducible transcription factor glucocorticoid receptor (GR). However, how these stress responses coordinately regulate cellular metabolism is still unknown. In this study, we demonstrated that either antisense TRX expression or cellular treatment with H2O2 negatively modulates GR function and decreases glucocorticoid-inducible gene expression. Impaired cellular response to glucocorticoids is rescued by overexpression of TRX, most possibly through the functional replenishment of the GR. Moreover, not only the ligand binding domain but the DNA binding domain of the GR is also suggested to be a direct target of TRX. Together, we here present evidence showing that cellular glucocorticoid responsiveness is coordinately modulated by redox state and TRX level and propose that cross talk between neuroendocrine control of stress responses and cellular antioxidant systems may be essential for mammalian adaptation processes.
Assuntos
Antioxidantes/metabolismo , Dexametasona/farmacologia , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo , Receptores de Glucocorticoides/fisiologia , Tiorredoxinas/biossíntese , Transcrição Gênica/efeitos dos fármacos , Animais , Northern Blotting , Células CHO , Células COS , Cricetinae , Citocinas/farmacologia , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/fisiologia , Diamida/farmacologia , Genes Reporter , Células HeLa , Humanos , Cinética , Mamíferos , Proteínas de Neoplasias/farmacologia , Oxirredução , Reação em Cadeia da Polimerase , Receptores de Glucocorticoides/biossíntese , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/farmacologia , TransfecçãoRESUMO
Oxytocin (OT) is widely used to induce labor in the clinical setting. However, its physiological role in normal human parturition remains unclear. We demonstrated the enhanced expression of OT receptor (OTR) mRNA in chorio-decidual tissue, using the polymerase chain reaction after the reverse transcriptase reaction (RT-PCR) and Northern blot analysis. OTR gene expression in chorio-decidual tissue increased fivefold during the course of parturition. In situ hybridization of fetal membrane revealed the expression of OTR mRNA in maternally derived decidual cells. The OTR mRNA was also detected in fetally derived chorionic trophoblast cells. Immunohistochemistry, using a newly developed anti-OTR monoclonal antibody, demonstrated the distribution of OTR protein in fetal membrane. The distribution pattern of OTR protein and OTR mRNA was identical, indicating that the regulation of OTR expression occurs mainly at the transcriptional level. These results support the idea that the expression of decidual OTR regulates the initiation and amplification of labor. The implications of these findings with regard to the pathogenesis of preterm labor are also discussed.
Assuntos
Córion/química , Decídua/química , Trabalho de Parto/metabolismo , RNA Mensageiro/análise , Receptores de Ocitocina/genética , Sequência de Bases , Northern Blotting , Feminino , Regulação da Expressão Gênica , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Gravidez , Receptores de Ocitocina/análiseRESUMO
We previously identified a novel TATA-binding protein (TBP)-interacting protein (TIP120) from the rat liver. Here, in an RNA polymerase II (RNAP II)-reconstituted transcription system, we demonstrate that recombinant TIP120 activates the basal level of transcription from various kinds of promoters regardless of the template DNA topology and the presence of TFIIE/TFIIH and TBP-associated factors. Deletion analysis demonstrated that a 412-residue N-terminal domain, which includes an acidic region and the TBP-binding domain, is required for TIP120 function. Kinetic studies suggest that TIP120 functions during preinitiation complex (PIC) formation at the step of RNAP II/TFIIF recruitment to the promoter but not after the completion of PIC formation. Electrophoretic mobility shift assays showed that TIP120 enhanced PIC formation, and TIP120 also stimulated the nonspecific transcription and DNA-binding activity of RNAP II. These lines of evidence suggest that TIP120 is able to activate basal transcription by overcoming a kinetic impediment to RNAP II/TFIIF integration into the TBP (TFIID)-TFIIB-DNA-complex. Interestingly, TIP120 also stimulates RNAP I- and III-driven transcription and binds to RPB5, one of the common subunits of the eukaryotic RNA polymerases, in vitro. Furthermore, in mouse cells, ectopically expressed TIP120 enhances transcription from all three classes (I, II, and III) of promoters. We propose that TIP120 globally regulates transcription through interaction with basal transcription mechanisms common to all three transcription systems.
Assuntos
Regulação da Expressão Gênica , Fatores de Transcrição/metabolismo , Transcrição Gênica , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular , Proteínas de Ligação a DNA/metabolismo , Células Eucarióticas , Células HeLa , Humanos , Camundongos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , RNA Polimerase II/metabolismo , Coelhos , Ratos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteína de Ligação a TATA-Box , Fatores de Transcrição/genética , Ativação Transcricional , Células Tumorais CultivadasRESUMO
Perioperative ventricular tachycardia (VT) was treated with nifekalant hydrochloride, a pure potassium channel blocker in 2 patients with low left ventricular ejection fraction (LVEF). The first patient is a 34-year-old woman, a chronic hemodialysis patient in whom severe aortic stenosis due to structural valvular deterioration of the previously implanted tissue valve was diagnosed with her LVEF of 26.9%. She underwent urgent redo aortic valve replacement with a mechanical valve. Postoperatively a sustained VT developed. After she received direct-current (DC) shock, nifekalant hydrochloride was administered. The 2nd patient is a 44-year-old man who presented with severe congestive heart failure. A coronary angiogram revealed triple vessel disease as well as decreased LVEF of 16% and ischemic mitral regurgitation. He underwent triple coronary artery bypass grafting and mitral ring annuloplasty. A VT developed requiring DC shock during hemostasis. Nifekalant hydrochloride was given immediately. In both patients, nifekalant hydrochloride was given intravenously in a dose of 0.3 mg/kg followed by a continuous intravenous infusion at a dose of 0.4 mg/kg/hr. Our experience shows nifekalant hydrochloride is effective against perioperative VT, especially in patients with impaired left ventricular function since it has mild positive inotropic effect.
Assuntos
Antiarrítmicos/uso terapêutico , Assistência Perioperatória , Pirimidinonas/uso terapêutico , Taquicardia Ventricular/tratamento farmacológico , Função Ventricular Esquerda/efeitos dos fármacos , Adulto , Procedimentos Cirúrgicos Cardíacos , Eletrocardiografia , Feminino , Humanos , Masculino , Taquicardia Ventricular/fisiopatologiaRESUMO
BACKGROUND: Although the prognosis of type 1 autoimmune hepatitis is generally good with immunosuppressive treatment, the disease progresses in some patients despite the treatment. The prognosis may be determined by the clinical course. AIM: To evaluate the long-term prognosis and assess the predictive factors for a serious event, including the development of hepatocellular carcinoma or death. METHODS: Sixty-nine patients with type 1 autoimmune hepatitis were prospectively followed up regularly, with a median follow-up period of 96 months (49-201 months). RESULTS: During the follow-up period, three patients (4%) developed hepatocellular carcinoma, and two of these three patients died. Another patient died of liver failure. The 10-year survival rate was 98%, and the 10-year hepatocellular carcinoma-free rate was 93%. The four patients experiencing a serious event received higher maintenance doses of corticosteroid during their follow-up periods than those did not. However, serum alanine aminotransferase levels during the follow-up period were higher in these four patients than in the others. CONCLUSIONS: Persistent elevation of serum alanine amniotransferase levels during the follow-up period, rather than factors existing prior to medical treatment is considered to be an important prognostic factor, and it is indicated that poor outcomes may result from the resistance to immunosuppressive treatment.
Assuntos
Alanina Transaminase/sangue , Carcinoma Hepatocelular/sangue , Hepatite Autoimune/mortalidade , Neoplasias Hepáticas/sangue , Adolescente , Adulto , Idoso , Anti-Inflamatórios/administração & dosagem , Azatioprina/administração & dosagem , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/patologia , Colagogos e Coleréticos/administração & dosagem , Esquema de Medicação , Quimioterapia Combinada , Feminino , Hepatite Autoimune/sangue , Hepatite Autoimune/tratamento farmacológico , Humanos , Imunossupressores/administração & dosagem , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prednisolona/administração & dosagem , Estudos Prospectivos , Recidiva , Resultado do Tratamento , Ácido Ursodesoxicólico/administração & dosagemRESUMO
Regulators of G protein signaling (RGS), which act as GTPase activators, are a family of cytosolic proteins emerging rapidly as an important means of controlling G protein-mediated cell signals. The importance of RGS action has been verified in vitro for various kinds of cell function. Their in situ modes of action in intact cells are, however, poorly understood. Here we show that an increase in intracellular Ca(2+) evoked by membrane depolarization controls the RGS action on G protein activation of muscarinic K(+) (K(G)) channel in the heart. Acetylcholine-induced K(G) current exhibits a slow time-dependent increase during hyperpolarizing voltage steps, referred to as "relaxation." This reflects the relief from the decrease in available K(G) channel number induced by cell depolarization. This phenomenon is abolished when an increase in intracellular Ca(2+) is prevented. It is also abolished when a calmodulin inhibitor or a mutant RGS4 is applied that can bind to calmodulin but that does not accelerate GTPase activity. Therefore, an increase in intracellular Ca(2+) and the resultant formation of Ca(2+)/calmodulin facilitate GTPase activity of RGS and thus decrease the available channel number on depolarization. These results indicate a novel and probably general pathway that Ca(2+)-dependent signaling regulates the G protein cycle via RGS proteins.
Assuntos
Potenciais de Ação , Cálcio/metabolismo , Ácido Egtázico/análogos & derivados , Coração/fisiologia , Proteínas Heterotriméricas de Ligação ao GTP/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , Proteínas RGS/fisiologia , Animais , Calmodulina/antagonistas & inibidores , Células Cultivadas , Quelantes/farmacologia , Ácido Egtázico/farmacologia , Condutividade Elétrica , Transporte de Íons , Cinética , Mutação , Miocárdio/citologia , Miocárdio/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana/antagonistas & inibidores , Proteínas RGS/genética , Ratos , Ratos Endogâmicos WKYRESUMO
TLP (TBP-like protein), which is a new protein dis-covered by us, has a structure similar to that of the C-terminal conserved domain (CCD) of TBP, although its function has not yet been elucidated. We isolated cDNA and genomic DNA that encode chicken TLP (cTLP) and determined their structures. The predicted amino acid sequence of cTLP was 98 and 91% identical to that of its mammalian and Xenopus counterparts, respectively, and its translation product was ubiquitously observed in chicken tissues. FISH detection showed that chicken tlp and tbp genes were mapped at 3q2.6-2.8 and 3q2.4-2.6 of the same chromosome, respectively. Genome analysis revealed that the chicken tlp gene was spliced with five introns. Interestingly, the vertebrate tbp genes were also found to be split by five introns when we focused on the CCDs, and their splicing points were similar to those of tlp. On the contrary, another TBP-resembling gene of Drosophila, trf1, is split by only one intron, as is the Drosophila 's tbp gene. These results support our earlier assumption that vertebrate TLPs did not directly descend from Drosophila TRF1. On the basis of these results together with phylogenetical exam-ination, we speculate that tlp diverged from an ancestral tbp gene through a process of gene duplication and point mutations.
Assuntos
Galinhas/genética , Proteínas de Ligação a DNA/genética , Proteínas de Drosophila , Evolução Molecular , Fatores de Transcrição/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Éxons/genética , Expressão Gênica , Genoma , Hibridização in Situ Fluorescente , Íntrons/genética , Modelos Genéticos , Dados de Sequência Molecular , Filogenia , Mapeamento Físico do Cromossomo , Homologia de Sequência de Aminoácidos , Proteínas Semelhantes à Proteína de Ligação a TATA-Box , Proteína de Ligação a TATA-Box , Fatores de Transcrição/química , Fatores de Transcrição/metabolismoRESUMO
The Y box-binding protein (YB-1) binds to DNA sequences, present in the control regions of many genes, that contain an inverted CCAAT box. The binding activity of a nuclear factor, designated MDR-NF1, to an inverted CCAAT box in the promoter of the multidrug resistance 1 (MDR1) gene has previously been shown to be increased in nuclear extracts of cells exposed to UV radiation or various anticancer agents. The MDR-NF1 cDNA has now been cloned by screening a human colon library with an active fragment of the MDR1 promoter. The amino acid sequence encoded by the cloned cDNA was identical to that of YB-1. Northern blot analysis revealed that YB-1 mRNA was present in all human tissues examined. Rabbit antibodies were generated against synthetic peptides corresponding to YB-1, and indirect immunofluorescence microscopy with these antibodies showed that the concentration of YB-1 in all cisplatin-resistant cell lines examined was higher than that in the respective drug-sensitive parental cells. Transfection of human epidermoid cancer KB cells with a YB-1 antisense construct established two cell lines with reduced concentrations of YB-1. These transfectants showed increased sensitivity to cisplatin, mitomycin C, and UV radiation but not to vincristine, doxorubicin, camptothecin, or etoposide. Thus, YB-1 may protect cells from the cytotoxic effects of agents that induce cross-linking of DNA, suggesting a novel function of this ancestor DNA-binding protein.
Assuntos
Antineoplásicos/toxicidade , Proteínas Estimuladoras de Ligação a CCAAT , Cisplatino/toxicidade , Dano ao DNA , Proteínas de Ligação a DNA/fisiologia , Resistência a Múltiplos Medicamentos/genética , Mitomicina/toxicidade , Raios Ultravioleta , Sequência de Aminoácidos , Animais , Anticorpos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Neoplasias do Colo , Proteínas de Ligação a DNA/biossíntese , Feminino , Imunofluorescência , Humanos , Células KB , Masculino , Dados de Sequência Molecular , Fatores de Transcrição NFI , Proteínas Nucleares , Regiões Promotoras Genéticas , Coelhos , Proteínas Recombinantes/biossíntese , Fatores de Transcrição , Transfecção , Células Tumorais Cultivadas , Proteína 1 de Ligação a Y-BoxRESUMO
We developed a novel and efficient cDNA subtraction method to isolate rat hepatocellular carcinoma (HCC)-related genes. cDNAs from Solt-Farber procedure-driven HCCs were synthesized on Latex beads. The subtraction was accomplished by a simple centrifugation, PCR amplification, and dot blot screening. Among 2000 clones from the subtracted cDNA library, one clone with a full-length HCC-related cDNA was eventually obtained. Sequence analysis of this clone showed it to exhibit 90 and 60% similarity with the rat cysteine sulfinic acid decarboxylase (CSAD) and mammalian glutamic acid decarboxylases (GAD), respectively. Differences between our sequence data on CSAD and those reported previously were observed at two positions, which arose from a single amino acid substitution and frame shift mutation. The CSAD expression was restricted to the liver and kidney of rats. During hepatocarcinogenesis, expression of the CSAD mRNA and its protein was stimulated in the precancerous liver and maintained its high expression afterward. Interestingly, a high level of anti-CSAD autoantibody was detected in the HCC-bearing rats. The titer of anti-CSAD autoantibodies in these rats was 30-200 times higher than that in normal rats. The anti-CSAD autoantibody appeared in the precancerous state and was maintained afterward, and its pattern of appearance was similar to that of CSAD mRNAs and proteins. Thus, we propose that the high-titer CSAD autoantibody resulted from increased CSAD gene expression in the liver due to stimulation by the HCC. These results remind us of human autoimmune diseases including insulin-dependent diabetes mellitus and stiff-man syndrome, which are caused by autoantibodies against GAD.
Assuntos
Anticorpos Antineoplásicos/metabolismo , Autoanticorpos/metabolismo , Carboxiliases/genética , DNA Complementar/isolamento & purificação , DNA de Neoplasias/isolamento & purificação , Neoplasias Hepáticas Experimentais/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Carboxiliases/imunologia , Carboxiliases/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas Experimentais/enzimologia , Neoplasias Hepáticas Experimentais/imunologia , Masculino , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , RNA Mensageiro/análise , RNA Neoplásico/análise , Ratos , Ratos WistarRESUMO
Thioredoxin, a cellular thiol, functions as a self-defense mechanism in response to environmental stimuli, including oxidative stress. We first determined cellular levels of thioredoxin in several human bladder and prostatic cancer cell lines resistant to cis-diamminedichloroplatinum(II) (cisplatin). All cisplatin-resistant cell lines had much higher levels of thioredoxin than those in their drug-sensitive parental counterpart. We then, by introducing thioredoxin antisense expression plasmids into human bladder cancer T24 cells, established two bladder cancer cell lines that had decreased levels of thioredoxin. These thioredoxin antisense transfectants showed increased sensitivity to cisplatin and also to other superoxide-generating agents, i.e., doxorubicin, mitomycin C, etoposide, and hydrogen peroxide, as well as to UV irradiation, but not to the tubulin-targeting agents, vincristine, and colchicine. Cellular levels of thioredoxin thus appear to limit sensitivity to various superoxide-generating anticancer drugs in cancer cells.
Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Doxorrubicina/farmacologia , Etoposídeo/farmacologia , Mitomicina/farmacologia , Tiorredoxinas/metabolismo , DNA/metabolismo , Relação Dose-Resposta a Droga , Resistência a Medicamentos , Humanos , Células Tumorais CultivadasRESUMO
OBJECTIVE: The purpose of this study was to investigate how the opening direction of the mental foramen (MF) changes with age in a Japanese population using multi-detector computed tomography (MDCT). METHODS: Post-mortem MDCT scans of 121 Japanese subjects (66 males and 55 females) were carried out where all subjects possessed at least twenty teeth, including molar teeth, in the upper and lower jaws. Two angles of the mental foramen opening were measured, namely the superior-inferior angle in the coronal plane and anterior-posterior angle in the transverse plane, on the CT reconstructed images. The associations between age and these two angles were evaluated using a multiple regression analysis. RESULTS: For male subjects, the relationship between the superior-inferior angle and age was a quadratic curve (p < 0.001). This angle increased until the subject reached their early 50s and then the angle decreased with age. In the transverse plane, there was a linear relation between the anterior-posterior angle and age (p=0.002).It was noted also that the angle decreased with age. By contrast, however, no significant associations between the two angles and age for either measurement were noted for female subjects. This study demonstrated that the opening direction of the mental foramen changes with age in Japanese male subjects. By contrast this change in the opening direction of the mental foramen was not demonstrated in Japanese female subjects. In male subjects, the opening direction moves superiorly until the individual reaches their early 50s, and then moves inferiorly with advancing age. It also shifts from a posterior to an anterior position with age. CONCLUSION: These observed change differ from the results of previous studies. The findings could be useful for forensic science as they demonstrate a change in the position of mental foramen in a sample of contemporaneous male Japanese subjects.