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1.
Haematologica ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38867578

RESUMO

Information regarding follow-up duration after treatment for newly diagnosed diffuse large B-cell lymphoma (DLBCL) is important. However, a clear endpoint has yet to be established. We totally enrolled 2182 patients newly diagnosed with DLBCL between 2008 and 2018. The median age of the patients was 71 years. All patients were treated with rituximab- and anthracycline-based chemotherapies. Each overall survival (OS) was compared with the age- and sex-matched Japanese general population (GP) data. At a median follow-up of 3.4 years, 985 patients experienced an event and 657 patients died. Patients who achieved an event-free survival (EFS) at 36 months (EFS36) had an OS equivalent to that of the matched GP (standard mortality ratio [SMR], 1.17; P=0.1324), whereas those who achieved an EFS24 did not have an OS comparable to that of the matched GP (SMR, 1.26; P=0.0095). Subgroup analysis revealed that relatively old patients (>60 years), male patients, those with limited-stage disease, those with a good performance status, and those with low levels of soluble interleukin 2 receptor already had a comparable life expectancy to the matched GP at an EFS24. In contrast, relatively young patients had a shorter life expectancy than matched GP, even with an EFS36. In conclusion, an EFS36 was shown to be a more suitable endpoint for newly diagnosed DLBCL patients than an EFS24. Of note, younger patients require a longer EFS period than older patients in order to obtain an equivalent life expectancy to the matched GP.

2.
Br J Haematol ; 201(6): 1144-1152, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37067758

RESUMO

Recent advances in next-generation sequencing (NGS) have enabled the detection of subclinical minute FLT3-ITD. We selected 74 newly diagnosed, cytogenetically normal acute myeloid leukaemia (AML) samples in which FLT3-ITD was not detected by gel electrophoresis. We sequenced them using NGS and found minute FLT3-ITDs in 19 cases. We compared cases with clinically relevant FLT3-ITD (n = 37), cases with minute FLT3-ITD (n = 19) and cases without detectable FLT3-ITD (n = 55). Molecular characteristics (location and length) of minute FLT3-ITD were similar to those of clinically relevant FLT3-ITD. Survival of cases with minute FLT3-ITD was similar to that of cases without detectable FLT3-ITD, whereas the relapse rate within 1 year after onset was significantly higher in cases with minute FLT3-ITD. We followed 18 relapsed samples of cases with clinically FLT3-ITD-negative at diagnosis. Two of 3 cases with minute FLT3-ITD relapsed with progression to clinically relevant FLT3-ITD. Two of 15 cases in which FLT3-ITD was not detected by NGS relapsed with the emergence of minute FLT3-ITD, and one of them showed progression to clinically relevant FLT3-ITD at the second relapse. We revealed the clonal dynamics of subclinical minute FLT3-ITD in clinically FLT3-ITD-negative AML. Minute FLT3-ITD at the initial AML can expand to become a dominant clone at relapse.


Assuntos
Leucemia Mieloide Aguda , Recidiva Local de Neoplasia , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Tirosina Quinase 3 Semelhante a fms/genética , Mutação , Prognóstico
3.
Eur J Haematol ; 111(4): 620-627, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37465857

RESUMO

OBJECTIVES: The cryptic fusion oncogene NUP98::NSD1 is known to be associated with FLT3-ITD mutation in acute myeloid leukemia (AML), and an independent poor prognostic factor in pediatric AML. However, there are little data regarding the clinical significance of NUP98::NSD1 in adult cohort. METHODS: We conducted a multicenter retrospective study to investigate the prevalence, clinical characteristics, and prognostic impact of NUP98::NSD1 in adult FLT3-ITD-positive AML patients. RESULTS: In a total of 97 FLT3-ITD-positive AML patients, six cases (6.2%) were found to harbor the NUP98::NSD1 fusion transcript. NUP98::NSD1 positive cases had significantly higher platelet counts and a higher frequency of FAB-M4 morphology than NUP98::NSD1 negative cases. NUP98::NSD1 was found to be mutually exclusive with NPM1 mutation, and was accompanied by the WT1 mutation in three of the six cases. The presence of NUP98::NSD1 fusion at the time of diagnosis predicted poor response to cytarabine-anthracycline-based intensive induction chemotherapy (induction failure rate: 83% vs. 36%, p = .038). Five of the six cases with NUP98::NSD1 underwent allogeneic hematopoietic stem cell transplantation (HSCT). Two of the five cases have successfully maintained remission, with one of them being rescued through a second HSCT. CONCLUSIONS: Detecting NUP98::NSD1 in adult FLT3-ITD-positive AML is crucial to recognizing chemotherapy-resistant group.


Assuntos
Leucemia Mieloide Aguda , Criança , Humanos , Adulto , Estudos Retrospectivos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Prognóstico , Mutação , Tirosina Quinase 3 Semelhante a fms/genética , Histona-Lisina N-Metiltransferase/genética
4.
J Mol Cell Cardiol ; 164: 42-50, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34826768

RESUMO

Roles of mitochondria in sinoatrial nodal cells (SANCs) have not been fully clarified. We have previously demonstrated that mitochondrial Ca2+ efflux through the Na+-Ca2+ exchanger, NCXm, modulates sarcoplasmic reticulum (SR) Ca2+ content and automaticity of HL-1 cardiomyocytes. In this study, we extended this line of investigation to clarify the spatial and functional association between mitochondria and local calcium release (LCR) from the SR in murine SANCs. High-speed two dimensional (2D) and confocal line-scan imaging of SANCs revealed that LCRs in the early phase of the Ca2+ transient cycle length (CL) appeared with a higher probability near mitochondria. Although LCR increased toward the late phase of CL, no significant difference was noted in the occurrence of late LCRs near and distant from mitochondria. LCRs, especially in the late phase of CL, induced temporal and spatial heterogeneity of the Ca2+ transient amplitude. Attenuating mitochondrial Ca2+ efflux using an NCXm inhibitor, CGP-37157 (1 µM), reduced the amplitude, duration and size of LCR. It also attenuated early LCR occurrence, and simultaneously prolonged LCR period and CL. Additionally, CGP-37157 reduced caffeine-induced Ca2+ transient. Therefore, the inhibitory effect on LCR was attributable to the reduction of the SR Ca2+ content through NCXm inhibition. No obvious off-target effects of 1 µM CGP-37157 were found on T- and L-type voltage-gated Ca2+ currents and hyperpolarization-activated inward current. Taken together, these results suggest that mitochondria are involved in LCR generation by modulating the SR Ca2+ content through NCXm-mediated Ca2+ efflux in murine SANCs.


Assuntos
Cálcio , Mitocôndrias , Nó Sinoatrial , Potenciais de Ação , Animais , Cálcio/metabolismo , Sinalização do Cálcio/fisiologia , Camundongos , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Retículo Sarcoplasmático/metabolismo , Nó Sinoatrial/citologia , Nó Sinoatrial/metabolismo , Trocador de Sódio e Cálcio/metabolismo
5.
Rinsho Ketsueki ; 59(12): 2594-2599, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-30626795

RESUMO

An 80-year-old female with fever, edema in the lower extremities, and marked eosinophilia was referred to our hospital. Based on the presence of the Philadelphia chromosome, she was diagnosed with chronic myeloid leukemia (CML). Although imatinib induced a complete cytogenetic response (CCyR), CML relapsed after 28 months of starting it. A CCyR was achieved again by nilotinib but was lost after about 14 months. Only transient response occurred to dasatinib, and the patient died. At relapse, neutrophilia was more predominant than eosinophilia. We reviewed 6 patients with CML whose eosinophil rate in the peripheral blood was >50%. Most patients were males with palpable splenomegaly and had cardiac disorders, peripheral vascular disease, or pleural effusion. Typically, CML causes neutrophil-predominant leukocytosis. However, a subgroup of CML with marked eosinophilia resembles chronic eosinophilic leukemia or idiopathic hypereosinophilic syndrome.


Assuntos
Eosinofilia/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Dasatinibe/uso terapêutico , Eosinofilia/tratamento farmacológico , Evolução Fatal , Feminino , Humanos , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Masculino , Cromossomo Filadélfia , Inibidores de Proteínas Quinases , Recidiva
6.
Am J Physiol Cell Physiol ; 310(5): C337-47, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26741144

RESUMO

Glucagon-like peptide-1 (GLP-1) is an intestinally derived blood glucose-lowering hormone that potentiates glucose-stimulated insulin secretion from pancreatic ß-cells. The secretagogue action of GLP-1 is explained, at least in part, by its ability to stimulate cAMP production so that cAMP may facilitate the release of Ca(2+) from inositol trisphosphate receptor (IP3R)-regulated Ca(2+) stores. However, a quantitative model has yet to be provided that explains the molecular mechanisms and dynamic processes linking GLP-1-stimulated cAMP production to Ca(2+) mobilization. Here, we performed simulation studies to investigate how GLP-1 alters the abilities of Ca(2+) and IP3 to act as coagonists at IP3R Ca(2+) release channels. A new dynamic model was constructed based on the Kaftan model, which demonstrates dual steady-state allosteric regulation of the IP3R by Ca(2+) and IP3. Data obtained from ß-cells were then analyzed to understand how GLP-1 facilitates IP3R-mediated Ca(2+) mobilization when UV flash photolysis is used to uncage Ca(2+) and IP3 intracellularly. When the dynamic model for IP3R activation was incorporated into a minimal cell model, the Ca(2+) transients and oscillations induced by GLP-1 were successfully reconstructed. Simulation studies indicated that transient and oscillatory responses to GLP-1 were produced by sequential positive and negative feedback regulation due to fast activation and slow inhibition of the IP3R by Ca(2+). The slow rate of Ca(2+)-dependent inhibition was revealed to provide a remarkable contribution to the time course of the decay of cytosolic Ca(2+) transients. It also served to drive and pace Ca(2+) oscillations that are significant when evaluating how GLP-1 stimulates insulin secretion.


Assuntos
Cálcio/metabolismo , Citoplasma/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Células Secretoras de Insulina/metabolismo , Animais , AMP Cíclico/metabolismo , Citosol/metabolismo , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Glucose/metabolismo , Insulina/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Camundongos , Fragmentos de Peptídeos/farmacologia
7.
Respir Med Case Rep ; 44: 101867, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37229484

RESUMO

An 80-year-old man diagnosed with primary macroglobulinemia 7 years earlier had been treated with cyclophosphamide, following which he developed dyspnea on exertion. Cyclophosphamide was discontinued. The patient's dyspnea, however, failed to improve. Right heart catheterization (RHC) revealed precapillary pulmonary hypertension (PH). He was transferred to our institution for further examination. Prior use of cyclophosphamide was the patient's only risk factor for PH, and cyclophosphamide use was considered as a possible cause of PH in this case. He was treated with tadalafil and dyspnea gradually improved. A follow-up RHC exhibited improvement in mean pulmonary arterial pressure and pulmonary vascular resistance.

8.
Sci Rep ; 12(1): 19529, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376413

RESUMO

Retinal photoreceptor cells, rods and cones, convert photons of light into chemical and electrical signals as the first step of the visual transduction cascade. Although the chemical processes in the phototransduction system are very similar to each other in these photoreceptors, the light sensitivity and time resolution of the photoresponse in rods are functionally different than those in the photoresponses of cones. To systematically investigate how photoresponses are divergently regulated in rods and cones, we have developed a detailed mathematical model on the basis of the Hamer model. The current model successfully reconstructed light intensity-, ATP- and GTP-dependent changes in concentrations of phosphorylated visual pigments (VPs), activated transducins (Tr*s) and phosphodiesterases (PDEs) in rods and cones. In comparison to rods, the lower light sensitivity of cones was attributed not only to the lower affinity of activated VPs for Trs but also to the faster desensitization of the VPs. The assumption of an intermediate inactive state, MIIi, in the thermal decay of activated VPs was essential for inducing faster inactivation of VPs in rods, and possibly also in cones.


Assuntos
Fotofobia , Células Fotorreceptoras Retinianas Bastonetes , Humanos , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Células Fotorreceptoras Retinianas Cones/metabolismo , Transdução de Sinal Luminoso/fisiologia , Transducina/metabolismo
9.
Am J Physiol Cell Physiol ; 301(4): C792-803, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21734192

RESUMO

Glucagon-like peptide-1 (GLP-1) elevates intracellular concentration of cAMP ([cAMP]) and facilitates glucose-dependent insulin secretion in pancreatic ß-cells. There has been much evidence to suggest that multiple key players such as the GLP-1 receptor, G(s) protein, adenylate cyclase (AC), phosphodiesterase (PDE), and intracellular Ca(2+) concentration ([Ca(2+)]) are involved in the regulation of [cAMP]. However, because of complex interactions among these signaling factors, the kinetics of the reaction cascade as well as the activities of ACs and PDEs have not been determined in pancreatic ß-cells. We have constructed a minimal mathematical model of GLP-1 receptor signal transduction based on experimental findings obtained mostly in ß-cells and insulinoma cell lines. By fitting this theoretical reaction scheme to key experimental records of the GLP-1 response, the parameters determining individual reaction steps were estimated. The model reconstructed satisfactorily the dynamic changes in [cAMP] and predicted the activities of cAMP effectors, protein kinase A (PKA), and cAMP-regulated guanine nucleotide exchange factor [cAMP-GEF or exchange protein directly activated by cAMP (Epac)] during GLP-1 stimulation. The simulations also predicted the presence of two sequential desensitization steps of the GLP1 receptor that occur with fast and very slow reaction rates. The cross talk between glucose- and GLP-1-dependent signal cascades for cAMP synthesis was well reconstructed by integrating the direct regulation of AC and PDE by [Ca(2+)]. To examine robustness of the signaling system in controlling [cAMP], magnitudes of AC and PDE activities were compared in the presence or absence of GLP-1 and/or the PDE inhibitor IBMX.(1).


Assuntos
Biologia Computacional/métodos , Células Secretoras de Insulina/fisiologia , Receptores de Glucagon/metabolismo , Transdução de Sinais/fisiologia , Análise de Sistemas , Animais , Receptor do Peptídeo Semelhante ao Glucagon 1 , Modelos Biológicos , Receptores de Glucagon/genética
10.
Am J Physiol Heart Circ Physiol ; 301(6): H2285-94, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21984539

RESUMO

Ca(+) sparklets are subcellular Ca(2+) signals produced by the opening of sarcolemmal L-type Ca(2+) channels. Ca(2+) sparklet activity varies within the sarcolemma of arterial myocytes. In this study, we examined the relationship between Ca(2+) sparklet activity and sarcoplasmic reticulum (SR) Ca(2+) accumulation and release in cerebral arterial myocytes. Our data indicate that the SR is a vast organelle with multiple regions near the sarcolemma of these cells. Ca(2+) sparklet sites were located at or <0.2 µm from SR-sarcolemmal junctions. We found that while Ca(2+) sparklets increase the rate of SR Ca(2+) refilling in arterial myocytes, their activity did not induce regional variations in SR Ca(2+) content or Ca(2+) spark activity. In arterial myocytes, L-type Ca(2+) channel activity was independent of SR Ca(2+) load. This ruled out a potential feedback mechanism whereby SR Ca(2+) load regulates the activity of these channels. Together, our data suggest a model in which Ca(2+) sparklets contribute Ca(2+) influx into a cytosolic Ca(2+) pool from which sarco(endo)plasmic reticulum Ca(2+)-ATPase pumps Ca(2+) into the SR, indirectly regulating SR function.


Assuntos
Sinalização do Cálcio , Cálcio/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Sarcolema/metabolismo , Retículo Sarcoplasmático/metabolismo , Animais , Canais de Cálcio Tipo L/metabolismo , Artérias Cerebrais/metabolismo , Proteínas Luminescentes/biossíntese , Proteínas Luminescentes/genética , Microscopia Confocal , Microscopia de Fluorescência , Músculo Liso Vascular/citologia , Sinais Direcionadores de Proteínas , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes de Fusão/biossíntese , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Fatores de Tempo , Transfecção , Proteína Vermelha Fluorescente
11.
Am J Physiol Cell Physiol ; 298(2): C211-20, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19846755

RESUMO

Ca(+) sparklets are subcellular Ca(2+) signals produced by the opening of L-type Ca(2+) channels (LTCCs). In cerebral arterial myocytes, Ca(2+) sparklet activity varies regionally, resulting in low and high activity, "persistent" Ca(2+) sparklet sites. Although increased Ca(2+) influx via LTCCs in arterial myocytes has been implicated in the chain of events contributing to vascular dysfunction during acute hyperglycemia and diabetes, the mechanisms underlying these pathological changes remain unclear. Here, we tested the hypothesis that increased Ca(2+) sparklet activity contributes to higher Ca(2+) influx in cerebral artery smooth muscle during acute hyperglycemia and in an animal model of non-insulin-dependent, type 2 diabetes: the dB/dB mouse. Consistent with this hypothesis, acute elevation of extracellular glucose from 10 to 20 mM increased the density of low activity and persistent Ca(2+) sparklet sites as well as the amplitude of LTCC currents in wild-type cerebral arterial myocytes. Furthermore, Ca(2+) sparklet activity and LTCC currents were higher in dB/dB than in control myocytes. We found that activation of PKA contributed to higher Ca(2+) sparklet activity during hyperglycemia and diabetes. In addition, we found that the interaction between PKA and the scaffolding protein A-kinase anchoring protein was critical for the activation of persistent Ca(2+) sparklets by PKA in cerebral arterial myocytes after hyperglycemia. Accordingly, PKA inhibition equalized Ca(2+) sparklet activity between dB/dB and wild-type cells. These findings suggest that hyperglycemia increases Ca(2+) influx by increasing Ca(2+) sparklet activity via a PKA-dependent pathway in cerebral arterial myocytes and contributes to vascular dysfunction during diabetes.


Assuntos
Glicemia/metabolismo , Canais de Cálcio Tipo L/metabolismo , Sinalização do Cálcio , Diabetes Mellitus Tipo 2/metabolismo , Angiopatias Diabéticas/metabolismo , Hiperglicemia/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Proteínas de Ancoragem à Quinase A/metabolismo , Animais , Canais de Cálcio Tipo L/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Artérias Cerebrais/metabolismo , Colforsina/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Angiopatias Diabéticas/fisiopatologia , Modelos Animais de Doenças , Ativação Enzimática , Ativadores de Enzimas/farmacologia , Hiperglicemia/complicações , Hiperglicemia/fisiopatologia , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Potenciais da Membrana , Camundongos , Camundongos Knockout , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/fisiopatologia , Miócitos de Músculo Liso/efeitos dos fármacos , Proteína Quinase C-alfa/genética , Proteína Quinase C-alfa/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas/farmacologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Fatores de Tempo , Regulação para Cima
12.
Eur J Haematol ; 82(2): 143-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19018870

RESUMO

OBJECTIVES: Recent studies have indicated that patients who receive stem cell transplantation (SCT) and rituximab demonstrate an increased risk of developing hypogammaglobulinemia. Such hypogammaglobulinemia has been found to be due to delayed recovery of memory B cells with an abnormal cell marker expression and impaired immunoglobulin production in vitro. However, no predictive factors for the levels of immunoglobulin after autologous SCT and rituximab therapy have been reported. The aim of this study is to clarify the relationships between the FCGR3A-158V/F genotype and the levels of serum immunoglobulin after SCT. METHODS: A total of 24 non-Hodgkin's lymphoma (NHL) patients received autologous SCT with an adjuvant rituximab. The FCGR3A-158V/F genotype was determined in these patients. We also included ten NHL patients who received an identical conditioning regimen and autologous SCT but no rituximab as control patients. RESULTS: The levels of IgG were significantly lower in FCGR3A-158F homozygous patients (n = 9) in comparison to those in FCGR3A-158V carriers (n = 15). Moreover, the levels of IgG and IgA of FCGR3A-158F homozygous patients, but not those of FCGR3A-158V carriers, were significantly lower than those of control patients. CONCLUSIONS: The genotype of FCGR3A determines not only the response to rituximab, but also the levels of immunoglobulin after SCT and an adjuvant rituximab.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Imunoglobulinas/sangue , Linfoma não Hodgkin/terapia , Polimorfismo Genético , Receptores de IgG/genética , Adulto , Idoso , Anticorpos Monoclonais Murinos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Humanos , Linfoma não Hodgkin/sangue , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/genética , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Rituximab , Vincristina/administração & dosagem
13.
J Physiol ; 586(3): 859-73, 2008 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-18033817

RESUMO

Two distinct populations of interstitial cells of Cajal (ICC) exist within the tunica muscularis of the gastric antrum, and these cells serve different physiological functions. One population of ICC generates and actively propagates electrical slow waves, and the other population of ICC is innervated by excitatory and inhibitory motor neurons and mediates enteric motor neurotransmission. In spite of the key role of ICC in gastric excitability, little is known about the ionic conductances that underlie the functional diversity of these cells. In the present study we isolated ICC from the murine gastric antrum and investigated the Ca(2+)-dependent ionic conductances expressed by these cells using the patch clamp technique. Conductances in ICC were compared with those expressed in smooth muscle cells. The cells studied were identified by RT-PCR using cell-specific primers that included Myh11 (smooth muscle cells), Kit (ICC) and Uchl1 (enteric neurons) following electrophysiolgical recordings. Distinct ionic conductances were observed in Kit-positive cells. One group of ICC expressed a basal non-selective cation conductance (NSCC) that was inhibited by an increase in [Ca(2+)](i) in a calmodulin (CaM)-dependent manner. A second population of ICC generated spontaneous transient inward currents (STICs) and expressed a basal noisy NSCC that was facilitated by an increase in [Ca(2+)](i) in a CaM-dependent manner. The [Ca(2+)](i)-facilitated NSCC in ICC was blocked by the Cl(-) channel antagonists 4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid (DIDS), anthracene-9-carboxylate (9-AC) and niflumic acid. These data suggest that distinct NSCC are expressed in subpopulations of ICC and these conductances may underlie the functional differences of these cells within the gastric antrum.


Assuntos
Canais Iônicos/metabolismo , Plexo Mientérico/metabolismo , Miócitos de Músculo Liso/metabolismo , Antro Pilórico/metabolismo , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Animais , Antracenos/farmacologia , Cálcio/metabolismo , Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/metabolismo , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Neurônios Motores/metabolismo , Plexo Mientérico/citologia , Miócitos de Músculo Liso/citologia , Técnicas de Patch-Clamp , Potássio/metabolismo , Proteínas Proto-Oncogênicas c-kit/metabolismo , Antro Pilórico/citologia , Antro Pilórico/inervação
14.
Biol Blood Marrow Transplant ; 14(5): 568-75, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18410899

RESUMO

We retrospectively evaluated the outcomes of 37 adult patients with acute lymphoblastic leukemia (ALL) undergoing allogeneic hematopoietic stem cell transplantation (allo-SCT) conditioned with medium-dose VP-16 (VP, 30 mg/kg), cyclophosphamide (CY, 120 mg/kg), and fractionated total-body irradiation (TBI, 12 Gy) (medium-dose VP/CY/TBI). The median age of the patients was 26 years. Thirteen patients underwent transplantation from HLA-matched related donors (MRD), 18 patients underwent transplantation from HLA-matched unrelated donors (MUD), and 6 patients underwent transplantation from HLA-mismatched donors (MMD). Thirty-two patients received bone marrow and 4 patients received peripheral blood stem cells. Ten patients were Philadelphia chromosome-positive (Ph(+)) and 35 patients were in complete remission (CR) at transplantation. All of the patients achieved engraftment, and grade 3 organ toxicity before engraftment occurred in 27 patients. Grade II-III acute graft-versus-host disease (GVHD) and chronic GVHD (cGVHD) occurred in 15 and 18 patients, respectively. No patient developed grade IV acute GVHD (aGVHD) or died of GVHD. At median follow-up of 35.1 months, 32 patients were alive and all Ph(+) patients were alive. Three patients died of relapse and 2 died of transplant-related mortality (TRM). The actuarial 3-year overall survival (OS) rate, relapse rate, and TRM rate were 89.2%, 8.1%, and 5.4%, respectively. Non-CR at transplantation, MRD, and no aGVHD were significant adverse prognostic factors for survival. Medium-dose VP/CY/TBI for adult ALL patients was associated with lower relapse rate and no increase in toxicity, resulting in better survival.


Assuntos
Ciclofosfamida/administração & dosagem , Etoposídeo/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Condicionamento Pré-Transplante/métodos , Adolescente , Adulto , Ciclofosfamida/toxicidade , Etoposídeo/toxicidade , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/radioterapia , Prognóstico , Indução de Remissão , Estudos Retrospectivos , Análise de Sobrevida , Condicionamento Pré-Transplante/efeitos adversos , Transplante Homólogo , Resultado do Tratamento , Irradiação Corporal Total
15.
Yakugaku Zasshi ; 136(3): 467-71, 2016.
Artigo em Japonês | MEDLINE | ID: mdl-26935088

RESUMO

Upon elevation of plasma glucose concentration, pancreatic ß-cells generate bursts of action potentials to induce cyclic changes in [Ca(2+)]i regulating insulin release. Glucose-dependent insulin secretion is synergistically enhanced by glucagon-like peptide-1 (GLP-1), which increases [cAMP]i and activates protein kinase A (PKA) and exchange protein activated by cAMP (Epac). The insulinotropic effect of GLP-1 is mediated, at least in part, by modulating multiple ion channels/transporters at the plasma membrane and ER through PKA- and EPAC-dependent mechanisms, which increase membrane excitability and intracellular Ca(2+) release. However, because of complex interactions between multiple cellular factors involved in the GLP-1 effects, quantitative aspects of the molecular/ionic mechanisms have not yet been determined. We thus performed simulation studies and mathematical analysis to investigate how GLP-1 signals control [cAMP]i and subsequently modify the bursting activities and Ca(2+) dynamics. First, a GLP-1 receptor signal transduction model was developed and introduced to our ß-cells model. Secondly, modulatory effects of PKA/Epac on ion channels/transporters were incorporated based on experimental studies. Increases in the frequency and duration of the bursting activity observed during GLP-1 stimulation were well reconstructed by our model, and lead potential analysis quantitatively determined the functional role of each ion channel/transporter in modifying the burst pattern. Finally, an IP3R model was developed to reproduce GLP-1-induced Ca(2+) transients/oscillations. Instantaneous equilibrium analysis and bifurcation analysis also elucidated the quantitative mechanisms involved in generating IP3R-mediated Ca(2+) mobilization. The results of this theoretical analysis of the effects of GLP-1 on membrane excitability/Ca(2+) dynamics are discussed in this review.


Assuntos
Cálcio/fisiologia , Peptídeo 1 Semelhante ao Glucagon/fisiologia , Receptor do Peptídeo Semelhante ao Glucagon 1/fisiologia , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/fisiologia , Potenciais de Ação , Glicemia/metabolismo , Cálcio/metabolismo , Membrana Celular/fisiologia , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Humanos , Insulina/metabolismo , Secreção de Insulina , Modelos Teóricos , Transdução de Sinais/fisiologia
16.
J Comp Neurol ; 493(2): 193-206, 2005 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-16255030

RESUMO

Autonomic neurotransmission is thought to occur via a loose association between nerve varicosities and smooth muscle cells. In the gastrointestinal tract ultrastructural studies have demonstrated close apposition between enteric nerves and intramuscular interstitial cells of Cajal (ICC-IM) in the stomach and colon and ICC in the deep muscular plexus (ICC-DMP) of the small intestine. In the absence of ICC-IM, postjunctional neural responses are compromised. Although membrane specializations between nerves and ICC-IM have been reported, the molecular identity of these specializations has not been studied. Here we have characterized the expression and distribution of synapse-associated proteins between nerve terminals and ICC-IM in the murine stomach. Transcripts for the presynaptic proteins synaptotagmin, syntaxin, and SNAP-25 were detected. Synaptotagmin and SNAP-25-immunopositive nerve varicosities were concentrated in varicose regions of motor nerves and were closely apposed to ICC-IM but not smooth muscle. W/W(V) mice were used to examine the expression and distribution of synaptic proteins in the absence of ICC-IM. Transcripts encoding synaptotagmin, syntaxin, and SNAP-25 were detected in W/W(V) tissues. In the absence of ICC-IM, synaptotagmin and SNAP-25 were localized to nerve varicosities. Reverse transcriptase polymer chain reaction (RT-PCR) and immunohistochemistry demonstrated the expression of postsynaptic density proteins PSD-93 and PSD-95 in the stomach and expression levels of PSD-93 and PSD-95 were reduced in W/W(V) mutants. These data support the existence of synaptic specializations between enteric nerves and ICC-IM in gastric tissues. In the absence of ICC-IM, components of the synaptic vesicle docking and fusion machinery is trafficked and concentrated in enteric nerve terminals.


Assuntos
Sistema Nervoso Entérico/ultraestrutura , Neurônios Motores/ultraestrutura , Músculo Liso/ultraestrutura , Vias Neurais/ultraestrutura , Estômago/ultraestrutura , Sinapses/ultraestrutura , Animais , Comunicação Celular/fisiologia , Sistema Nervoso Entérico/fisiologia , Motilidade Gastrointestinal/fisiologia , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Neurônios Motores/fisiologia , Músculo Liso/inervação , Músculo Liso/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Vias Neurais/fisiologia , Junção Neuromuscular/fisiologia , Junção Neuromuscular/ultraestrutura , Proteínas Qa-SNARE/metabolismo , Estômago/inervação , Sinapses/metabolismo , Vesículas Sinápticas/metabolismo , Proteína 25 Associada a Sinaptossoma/metabolismo , Sinaptotagminas/metabolismo
17.
Proc Biol Sci ; 271(1554): 2293-6, 2004 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-15539355

RESUMO

The adaptation of death-feigning (thanatosis), a subject that has been overlooked in evolutionary biology, was inferred in a model prey-and-predator system. We studied phenotypic variation among individuals, fitness differences, and the inheritance of death-feigning behaviour in the red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). Two-way artificial selections for the duration of death-feigning, over 10 generations, showed a clear direct response in the trait and a correlated response in the frequency of death-feigning, thus indicating variation and inheritance of death-feigning behaviour. A comparison of the two selected strains with divergent frequencies of death-feigning showed a significant difference in the fitness for survival when a model predator, a female Adanson jumper spider, Hasarius adansoni Audouin (Araneomophae: Salticidae), was presented to the beetles. The frequency of predation was lower among beetles from strains selected for long-duration than among those for short-duration death-feigning. The results indicate the possibility of the evolution of death-feigning under natural selection.


Assuntos
Adaptação Biológica/fisiologia , Comportamento Animal/fisiologia , Morte , Enganação , Tribolium/fisiologia , Animais , Feminino , Masculino , Observação , Comportamento Predatório/fisiologia , Seleção Genética , Aranhas/fisiologia
18.
Anal Sci ; 19(5): 721-5, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12769372

RESUMO

A colloidal powder was prepared by fixing polyaniline (PANI, conducting polymer), poly(vinyl alcohol) (PVA, surfactant stabilizer) and a suitable dopant anion to silica-gel powder. This hydrophilic composite colloidal particle incorporates anions with the protonation of PANI in an acidic solution. The anion can be exchanged with other anions when the colloid is immersed in an acidic solution. Thus, the PANI colloid works as an ion exchanger. The ion-exchange properties on the composite colloidal powder were investigated. Anions were successfully and easily exchanged in the order Br- < Cl- < NO3- < ClO4- < SCN-. This ion-exchange selectivity corresponds largely to the ion-exchange equilibrium constants, which are based on a hydrophobic interaction between the anion and colloid. However, this ion-exchange selectivity does not agree simply with the lipophilic order, but is instead explainable by a gap in the effective ion-exchange capacity due to a size effect between the micropore on the colloidal particle formed by the dopant anion in polymerization and anion sizes in the hydrophobic environment.

19.
Neurosurgery ; 68(6): 1733-42; discussion 1742, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21311377

RESUMO

BACKGROUND: The donor cell culture in animal serum-free medium is important for the clinical application of cell transplantation therapy. Recently, human-derived platelet lysate (PL) gained interest as a substitute for fetal calf serum (FCS), but there are no studies that evaluate the validity of human bone marrow stromal cells (hBMSCs) expanded with PL-containing medium for central nervous system disorders. OBJECTIVE: To test the hypothesis that hBMSCs expanded with FCS-free, PL-containing medium can promote functional recovery after cerebral infarct. METHODS: hBMSCs were cultured in the FCS- or PL-containing medium. Cell-growth kinetics were analyzed. The vehicle or hBMSCs was stereotactically transplanted into the ipsilateral striatum of the rats subjected to permanent middle cerebral artery occlusion 7 days after the insult. Motor function was assessed for 8 weeks, and the fate of transplanted hBMSCs was examined using immunohistochemistry. RESULTS: There was no significant difference in hBMSC expansion between the 2 groups. Transplantation of hBMSCs expanded with the FCS- or PL-containing medium equally promoted functional recovery compared with the vehicle group. Histological analysis revealed that there were no significant differences in their migration, survival, and neural differentiation in the infarct brain between the 2 groups. CONCLUSION: hBMSCs expanded with PL-containing medium retained their capacity of migration, survival, and differentiation and significantly promoted functional recovery when stereotactically transplanted into the infarct brain. The PL may be a clinically valuable and safe substitute for FCS in expanding hBMSCs to regenerate the infarct brain.


Assuntos
Transplante de Medula Óssea/métodos , Técnicas de Cultura de Células/métodos , Meios de Cultura Livres de Soro , Infarto da Artéria Cerebral Média/cirurgia , Células Estromais/citologia , Células Estromais/transplante , Animais , Diferenciação Celular , Movimento Celular/fisiologia , Sobrevivência Celular/fisiologia , Humanos , Imuno-Histoquímica , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica
20.
Transl Stroke Res ; 2(3): 294-306, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24323650

RESUMO

This study was aimed to test the hypothesis that human bone marrow stromal cells (hBMSC) expanded in fetal calf serum (FCS)-free, platelet lysate (PL)-containing medium would retain their capacity of migration, survival, and neural differentiation when transplanted into the infarct brain, using serial in vivo magnetic resonance imaging (MRI). Cell growth kinetic analysis revealed that hBMSC maintain their proliferative activity when cultured either in conventional FCS-containing medium or FCS-free, PL-containing medium. Subsequently, hBMSC were labeled with a superparamagnetic iron oxide agent and were stereotactically transplanted into the ipsilateral striatum of rats at 7 days after permanent middle cerebral artery occlusion. Serial MRI performed over 8 weeks revealed that they retain their migratory capacity towards the cerebral infarct. Moreover, double fluorescence immunohistochemistry also revealed that they preserve their capacity of differentiation into the neural cells in the peri-infarct area. The hBMSC expanded in the FCS-free, PL-containing medium retain their capacity of migration, survival, and differentiation when stereotactically transplanted into the infarct brain. The present findings strongly suggest the clinical utility of PL as a substitute to expand autologous hBMSC for cerebral infarct in the future.

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