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1.
Eur Psychiatry ; 32: 34-41, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26802982

RESUMO

BACKGROUND: Postgraduate medical trainees experience high rates of burnout, but evidence regarding psychiatric trainees is missing. We aim to determine burnout rates among psychiatric trainees, and identify individual, educational and work-related factors associated with severe burnout. METHODS: In an online survey psychiatric trainees from 22 countries were asked to complete the Maslach Burnout Inventory (MBI-GS) and provide information on individual, educational and work-related parameters. Linear mixed models were used to predict the MBI-GS scores, and a generalized linear mixed model to predict severe burnout. RESULTS: This is the largest study on burnout and training conditions among psychiatric trainees to date. Complete data were obtained from 1980 out of 7625 approached trainees (26%; range 17.8-65.6%). Participants were 31.9 (SD 5.3) years old with 2.8 (SD 1.9) years of training. Severe burnout was found in 726 (36.7%) trainees. The risk was higher for trainees who were younger (P<0.001), without children (P=0.010), and had not opted for psychiatry as a first career choice (P=0.043). After adjustment for socio-demographic characteristics, years in training and country differences in burnout, severe burnout remained associated with long working hours (P<0.001), lack of supervision (P<0.001), and not having regular time to rest (P=0.001). Main findings were replicated in a sensitivity analysis with countries with response rate above 50%. CONCLUSIONS: Besides previously described risk factors such as working hours and younger age, this is the first evidence of negative influence of lack of supervision and not opting for psychiatry as a first career choice on trainees' burnout.


Assuntos
Esgotamento Profissional , Psiquiatria/estatística & dados numéricos , Tolerância ao Trabalho Programado/psicologia , Adulto , Esgotamento Profissional/diagnóstico , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/etiologia , Escolha da Profissão , Demografia , Educação Médica Continuada/métodos , Feminino , Humanos , Masculino , Serviços de Saúde Mental/organização & administração , Pessoa de Meia-Idade , Inventário de Personalidade , Fatores de Risco , Fatores Socioeconômicos , Inquéritos e Questionários
2.
Oecologia ; 172(4): 949-60, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23232939

RESUMO

We investigated the nitrogen and carbohydrate allocation patterns of trees under heterogeneous light environments using saplings of the devil maple tree (Acer diabolicum) with Y-shaped branches. Different branch groups were created: all branches of a sapling exposed to full light (L-branches), all branches exposed to full shade (S-branches), and half of the branches of a sapling exposed to light (HL-branches) and the other half exposed to shade (HS-branches). Throughout the growth period, nitrogen was preferentially allocated to HL-branches, whereas nitrogen allocation to HS-branches was suppressed compared to L- and S-branches. HL-branches with the highest leaf nitrogen content (N(area)) also had the highest rates of growth, and HS-branches with the lowest N(area) had the lowest observed growth rates. In addition, net nitrogen assimilation, estimated using a photosynthesis model, was strongly correlated with branch growth and whole-plant growth. In contrast, patterns of photosynthate allocation to branches and roots were not affected by the light conditions of the other branch. These observations suggest that tree canopies develop as a result of resource allocation patterns, where the growth of sun-lit branches is favoured over shaded branches, which leads to enhanced whole-plant growth in heterogeneous light environments. Our results indicate that whole-plant growth is enhanced by the resource allocation patterns created for saplings in heterogeneous light environments.


Assuntos
Acer/crescimento & desenvolvimento , Acer/metabolismo , Luz , Nitrogênio/metabolismo , Metabolismo dos Carboidratos , Alocação de Recursos
3.
Transl Psychiatry ; 2: e188, 2012 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-23149452

RESUMO

To better understand the cellular pathogenetic mechanisms of fetal alcohol spectrum disorder (FASD) and the therapeutic benefit of stem cell treatment, we exposed pregnant rats to ethanol followed by intravenous administration of neural stem cells (NSCs) complexed with atelocollagen to the new born rats and studied recovery of GABAergic interneuron numbers and synaptic protein density in the anterior cingulate cortex, hippocampus and amygdala. Prenatal ethanol exposure reduced both parvalbumin-positive phenotype of GABAergic interneurons and postsynaptic density protein 95 levels in these areas. Intravenous NSC treatment reversed these reductions. Furthermore, treatment with NSCs reversed impaired memory/cognitive function and social interaction behavior. These experiments underscore an important role for synaptic remodeling and GABAergic interneuron genesis in the pathophysiology and treatment of FASD and highlight the therapeutic potential for intravenous NSC administration in FASD utilizing atelocollagen.


Assuntos
Transtornos do Espectro Alcoólico Fetal/terapia , Transtornos da Memória/terapia , Células-Tronco Neurais/transplante , Reconhecimento Psicológico , Tonsila do Cerebelo/metabolismo , Tonsila do Cerebelo/fisiopatologia , Animais , Animais Recém-Nascidos , Comportamento Animal , Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/fisiopatologia , Transtornos Cognitivos/terapia , Modelos Animais de Doenças , Feminino , Transtornos do Espectro Alcoólico Fetal/metabolismo , Transtornos do Espectro Alcoólico Fetal/fisiopatologia , Neurônios GABAérgicos/metabolismo , Giro do Cíngulo/metabolismo , Giro do Cíngulo/fisiopatologia , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Interneurônios/metabolismo , Transtornos da Memória/metabolismo , Transtornos da Memória/fisiopatologia , Gravidez , Ratos , Ratos Wistar , Comportamento Social , Transplante de Células-Tronco
4.
Br J Radiol ; 80(950): 85-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16854963

RESUMO

The purpose of this study was to objectively evaluate the registration accuracy of an automated temporal subtraction system of thin-section thoracic CT. The automated subtraction system was applied to data from 20 subjects with lung diseases. The registration accuracy was evaluated based on the concept of target registration error using 19 landmarks chosen at the bifurcations of segmental bronchi. The landmarks were identified, and the displacements of the landmarks were measured. The average displacements of the landmarks in x, y and z directions were 0.56 pixels+/-0.64 (SD), 0.56 pixels+/-0.62 (SD, standard deviation) and 0.28 sections+/-0.40 (SD), respectively. Differences in average displacements between the landmarks were not statistically significant. Our computer system demonstrated promising results. The average displacements of the landmarks were less than the dimensions of a voxel. Further study is necessary to determine whether such a computer system can improve the diagnostic performance of radiologists.


Assuntos
Pneumopatias/diagnóstico por imagem , Tomografia Computadorizada por Raios X/normas , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos
5.
J Neural Transm (Vienna) ; 113(3): 283-93, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15959844

RESUMO

The neuron-restrictive silencer factor (NRSF), or repressor element-1 silencing transcription factor (REST), is a transcription factor that mediates negative regulation of neuronal genes. NRSF represses multiple neuronal target genes in non-neuronal and neuronal precursor cells to regulate the proper timing of neuronal gene expression during neurogenesis. In the present study, we investigated the effects of ethanol and MEK inhibitor U0126 on the DNA binding activity of NRSF in neural stem cells prepared from rat embryos. Both ethanol and U0126 enhanced NRSF binding activity measured by the method based on the principal of electrophoretic mobility shift assay (EMSA) and decreased neuronal differentiation in a concentration dependent manner. Western blot analysis revealed that ethanol suppressed phosphorylation of extracellular signal-regulated kinase (ERK) without affecting expression of total ERK. These results suggest that ethanol-induced potentiation of NRSF binding activity underlies the mechanism of ethanol inhibition of neuronal differentiation and decreased neurogenesis.


Assuntos
Transtornos do Sistema Nervoso Induzidos por Álcool/metabolismo , Encéfalo/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Etanol/toxicidade , Neurônios/efeitos dos fármacos , Proteínas Repressoras/efeitos dos fármacos , Fatores de Transcrição/efeitos dos fármacos , Transtornos do Sistema Nervoso Induzidos por Álcool/fisiopatologia , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiopatologia , Diferenciação Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Depressores do Sistema Nervoso Central/toxicidade , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/genética , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 1/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Células-Tronco Pluripotentes/efeitos dos fármacos , Células-Tronco Pluripotentes/metabolismo , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Ratos , Ratos Wistar , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia
6.
Phys Rev Lett ; 93(4): 043201, 2004 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-15323759

RESUMO

Electron-DNA anion collisions were studied using an electrostatic storage ring with a merging electron-beam technique. The rate of neutral particles emitted in collisions started to increase from definite threshold energies, which increased regularly with ion charges in steps of about 10 eV. These threshold energies were almost independent of the length and sequence of DNA, but depended strongly on the ion charges. Neutral particles came from breaks of DNAs, rather than electron detachment. The step of the threshold energy increase approximately agreed with the plasmon excitation energy. It is deduced that plasmon excitation is closely related to the reaction mechanism.


Assuntos
DNA/química , Oligonucleotídeos/química , Ânions , Elétrons , Eletricidade Estática
7.
J Neural Transm (Vienna) ; 111(6): 667-81, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15168214

RESUMO

The neurotoxicity of conventional antipsychotic drugs has emerged as a potential pathogenic event in extrapyramidal side effects (EPS) and in their limited efficacy for negative-cognitive symptoms in schizophrenic patients. The atypical antipsychotics, recently developed, have superior therapeutic efficacy to treat not only positive symptoms but negative symptoms and cognitive dysfunctions with much lower potentials of side effects, although the influence of atypical antipsychotics on the regulation of neuronal survival has been less investigated. It is important to clarify the effects of typical and atypical antipsychotics on neuronal survival and their contributions to the therapeutic development and understanding of the pathophysiology of schizophrenia. We measured the neurotoxicity of two antipsychotic drug treatments, haloperidol and risperidone, in primary cultured rat cortical neurons. Immunoblotting and pharmacological agent analyses were used to determine the signal transduction changes implicated in the mechanisms of the neurotoxicity. Haloperidol induced apoptotic injury in cultured cortical neurons, but risperidone showed weak potential to injure the neurons. Treatment with haloperidol also led the reduction of phosphorylation levels of Akt, and activated caspase-3. The D2 agonist bromocriptine and 5-HT2A antagonist, ketanserin attenuated the haloperidol-induced neuronal toxicity. Moreover, brain-derived neurotrophic factor (BDNF) reduced the caspase-3 activity and protected neurons from haloperidol-induced apoptosis. BDNF also reversed the reduced levels of phosphorylation of Akt caused by treatment with haloperidol. Haloperidol but not risperidone induces caspase-dependent apoptosis by reducing cellular survival signaling, which possibly contributes to the differential clinical therapeutic efficacy and expression of side effects in schizophrenia.


Assuntos
Antagonistas de Dopamina/toxicidade , Haloperidol/toxicidade , Neurônios/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/efeitos dos fármacos , Proteínas Proto-Oncogênicas/efeitos dos fármacos , Risperidona/toxicidade , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Caspase 3 , Caspases/efeitos dos fármacos , Células Cultivadas , Embrião de Mamíferos , Imuno-Histoquímica , Neurônios/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Ratos , Ratos Wistar
8.
Eur J Clin Pharmacol ; 58(4): 247-52, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12136370

RESUMO

BACKGROUND: Zolmitriptan is a 5HT(1B/1D) receptor agonist effective in the acute treatment of migraine. Clinical trials in the USA and Europe have demonstrated the optimal oral therapeutic dose to be 2.5 mg. The 2.5-mg oral tablet has recently been licensed in Japan. OBJECTIVE: To compare the pharmacokinetics of zolmitriptan and its metabolites in Japanese and Caucasian subjects and evaluate the effect of gender on these pharmacokinetics in Japanese volunteers. METHODS: In this open, parallel-group study, 30 Japanese and 30 Caucasian volunteers (20-45 years) received a single 2.5-mg zolmitriptan tablet in the fasting state. Blood samples were taken up to 15 h post-dose to determine plasma concentrations of zolmitriptan and its active metabolite, 183C91. Urinary excretion of zolmitriptan, 183C91 and the inactive N-oxide and indole acetic acid metabolites were measured over 24 h. RESULTS: Japanese volunteers were, on average, smaller and lighter than Caucasian volunteers. Plasma-concentration profiles of zolmitriptan and 183C91 were similar in the two groups. Although geometric mean zolmitriptan and 183C91 area under the plasma concentration-time curve (AUC) and maximum plasma concentration (C(max)) were slightly higher in Japanese subjects (up to 20%), these differences were not considered to be of clinical relevance as the 90% confidence interval for the ratio of AUCs fell within pre-specified limits (0.67 to 1.5). Mean zolmitriptan and 183C91 half-lives were around 2.5 h for both populations. Urinary excretion of the four analytes was similar in Japanese and Caucasians. Plasma concentrations of zolmitriptan were higher in Japanese females than males (AUC 40% and C(max) 29% higher), consistent with the results previously obtained in Caucasians. CONCLUSION: Pharmacokinetic parameters of zolmitriptan were similar between Caucasian and Japanese volunteers.


Assuntos
Povo Asiático , Oxazolidinonas/farmacocinética , Agonistas do Receptor de Serotonina/farmacocinética , População Branca , Administração Oral , Adulto , Área Sob a Curva , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Oxazolidinonas/sangue , Oxazolidinonas/urina , Agonistas do Receptor de Serotonina/sangue , Agonistas do Receptor de Serotonina/urina , Fumar , Triptaminas
9.
EMBO J ; 20(19): 5421-30, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11574474

RESUMO

In cultured mammalian cells, the p38 mitogen-activated protein kinase (MAPK) pathway is activated in response to a variety of environmental stresses. How ever, there is little evidence from in vivo studies to demonstrate a role for this pathway in the stress response. We identified a Drosophila MAPK kinase kinase (MAPKKK), D-MEKK1, which can activate p38 MAPK. D-MEKK1 is structurally similar to the mammalian MEKK4/MTK1 MAPKKK. D-MEKK1 kinase activity was activated in animals under conditions of high osmolarity. Drosophila mutants lacking D-MEKK1 were hypersensitive to environmental stresses, including elevated temperature and increased osmolarity. In these D-MEKK1 mutants, activation of Drosophila p38 MAPK in response to stress was poor compared with activation in wild-type animals. These results suggest that D-MEKK1 regulation of the p38 MAPK pathway is critical for the response to environmental stresses in Drosophila.


Assuntos
Drosophila/enzimologia , Sistema de Sinalização das MAP Quinases , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Adaptação Biológica , Sequência de Aminoácidos , Animais , Meio Ambiente , Ativação Enzimática , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Proteínas Quinases p38 Ativadas por Mitógeno
10.
Proc Natl Acad Sci U S A ; 98(19): 10857-62, 2001 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-11553814

RESUMO

Antiangiogenic agents block the effects of tumor-derived angiogenic factors (paracrine factors), such as vascular endothelial growth factor (VEGF), on endothelial cells (EC), inhibiting the growth of solid tumors. However, whether inhibition of angiogenesis also may play a role in liquid tumors is not well established. We recently have shown that certain leukemias not only produce VEGF but also selectively express functional VEGF receptors (VEGFRs), such as VEGFR-2 (Flk-1, KDR) and VEGFR1 (Flt1), resulting in the generation of an autocrine loop. Here, we examined the relative contribution of paracrine (EC-dependent) and autocrine (EC-independent) VEGF/VEGFR signaling pathways, by using a human leukemia model, where autocrine and paracrine VEGF/VEGFR loops could be selectively inhibited by neutralizing mAbs specific for murine EC (paracrine pathway) or human tumor (autocrine) VEGFRs. Blocking either the paracrine or the autocrine VEGF/VEGFR-2 pathway delayed leukemic growth and engraftment in vivo, but failed to cure inoculated mice. Long-term remission with no evidence of disease was achieved only if mice were treated with mAbs against both murine and human VEGFR-2, whereas mAbs against human or murine VEGFR-1 had no effect on mice survival. Therefore, effective antiangiogenic therapies to treat VEGF-producing, VEGFR-expressing leukemias may require blocking both paracrine and autocrine VEGF/VEGFR-2 angiogenic loops to achieve remission and long-term cure.


Assuntos
Comunicação Autócrina , Fatores de Crescimento Endotelial/metabolismo , Leucemia Promielocítica Aguda/fisiopatologia , Linfocinas/metabolismo , Comunicação Parácrina , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Transdução de Sinais , Animais , Divisão Celular , Células Cultivadas , Técnicas de Cocultura , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Células HL-60 , Humanos , Leucemia Promielocítica Aguda/metabolismo , Camundongos , Invasividade Neoplásica , Transplante de Neoplasias , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/fisiopatologia , Neovascularização Patológica/fisiopatologia , Receptores de Fatores de Crescimento do Endotélio Vascular , Fatores de Tempo , Transplante Heterólogo , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
11.
J Nucl Med ; 42(7): 1005-10, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11438619

RESUMO

UNLABELLED: Recently, troglitazone has emerged as an insulin sensitizer for the treatment of type II diabetes. However, its effect on skeletal muscle glucose use (SMGU) has not been studied. METHODS: To investigate the effect of troglitazone on SMGU in patients with type II diabetes, we undertook skeletal muscle (18)F-FDG PET dynamic imaging under insulin clamping before and after administration of SMGU to 20 patients with type II diabetes. Data were compared with those for 12 age-matched healthy volunteers. RESULTS: The whole-body glucose disposal rate (GDR) was significantly lower in patients (29.9 +/- 9.83 micromol/min/kg) than in control subjects (55.6 +/- 16.5 micromol/min/kg, P < 0.01), as was the SMGU (patients, 3.27 +/- 2.17 micromol/min/kg; control subjects, 10.9 +/- 6.4 micromol/min/kg; P < 0.01). After the therapy, GDR significantly improved in patients (29.3 +/- 14.6 micromol/min/kg, P < 0.05), as did SMGU (5.06 +/- 2.11 micromol/min/kg, P < 0.05). When results for patients with and without hypertension were separately analyzed, a significant improvement in SMGU after troglitazone was seen in both normotensive and hypertensive patients (normotensive [n = 10]: baseline, 3.67 +/- 2.89 micromol/min/kg; after therapy, 5.28 +/- 2.61 micromol/min/kg; P < 0.05; hypertensive [n = 10]: baseline, 2.89 +/- 1.22 micromol/min/kg; after therapy, 4.72 +/- 1.39 micromol/min/kg; P < 0.05). GDR in patients with and without hypertension was significantly improved by troglitazone (normotensive: baseline, 17.9 +/- 10.2 micromol/min/kg; after therapy, 31.9 +/- 15.9 micromol/min/kg; P < 0.01; hypertensive: baseline, 39.6 +/- 15.1 micromol/min/kg; after therapy, 47.7 +/- 23.8 micromol/min/kg; P < 0.05). The plasma free fatty acid concentration during insulin clamping was not changed by troglitazone (baseline, 1.1 +/- 0.86 mEq/L; after therapy, 0.93 +/- 0.65 mEq/L; P = not significant). CONCLUSION: Troglitazone can improve whole-body insulin resistance through the improvement of SMGU but not through a decline in plasma free fatty acid concentration in patients with type II diabetes with or without hypertension.


Assuntos
Cromanos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Fluordesoxiglucose F18 , Glucose/metabolismo , Hipoglicemiantes/uso terapêutico , Resistência à Insulina , Músculo Esquelético/metabolismo , Compostos Radiofarmacêuticos , Tiazóis/uso terapêutico , Tiazolidinedionas , Tomografia Computadorizada de Emissão , Glicemia/análise , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Diabetes Mellitus Tipo 2/metabolismo , Ácidos Graxos não Esterificados/sangue , Feminino , Humanos , Hipertensão/complicações , Hipertensão/metabolismo , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Troglitazona
12.
Blood ; 97(11): 3354-60, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11369624

RESUMO

The chemokine, stromal cell-derived factor-1 (SDF1), is produced in the bone marrow and has been shown to modulate the homing of stem cells to this site by mediating chemokinesis and chemotaxis. Therefore, it was hypothesized that elevation of SDF1 level in the peripheral circulation would result in mobilization of primitive hematopoietic stem and progenitor cells. SDF1 plasma level was increased by intravenous injection of an adenoviral vector expressing SDF1alpha (AdSDF1) into severe combined immunodeficient mice. This resulted in a 10-fold increase in leukocyte count, a 3-fold increase in platelets, and mobilization of progenitors, including colony-forming units-granulocyte-macrophage to the peripheral circulation. In addition, AdSDF1 induced mobilization of cells with stem cell potential, including colony-forming units in spleen and long-term reconstituting cells. These data demonstrate that overexpression of SDF1 in the peripheral circulation results in the mobilization of hematopoietic cells with repopulating capacity, progenitor cells, and precursor cells. These studies lay the foundation for using SDF1 to induce mobilization of hematopoietic stem and progenitor cells in in vivo studies. (Blood. 2001;97:3354-3360)


Assuntos
Quimiocinas CXC/sangue , Células-Tronco Hematopoéticas/citologia , Adenoviridae/genética , Animais , Células da Medula Óssea/efeitos dos fármacos , Contagem de Células , Quimiocina CXCL12 , Quimiocinas CXC/genética , Expressão Gênica , Granulócitos , Transplante de Células-Tronco Hematopoéticas , Contagem de Leucócitos , Macrófagos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos SCID , Contagem de Plaquetas , Baço/citologia , Baço/efeitos dos fármacos , Células Estromais/metabolismo , Transfecção
13.
J Exp Med ; 193(9): 1005-14, 2001 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-11342585

RESUMO

Tyrosine kinase receptors for angiogenic factors vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1) are expressed not only by endothelial cells but also by subsets of hematopoietic stem cells (HSCs). To further define their role in the regulation of postnatal hematopoiesis and vasculogenesis, VEGF and Ang-1 plasma levels were elevated by injecting recombinant protein or adenoviral vectors expressing soluble VEGF(165), matrix-bound VEGF(189), or Ang-1 into mice. VEGF(165), but not VEGF(189), induced a rapid mobilization of HSCs and VEGF receptor (VEGFR)2(+) circulating endothelial precursor cells (CEPs). In contrast, Ang-1 induced delayed mobilization of CEPs and HSCs. Combined sustained elevation of Ang-1 and VEGF(165) was associated with an induction of hematopoiesis and increased marrow cellularity followed by proliferation of capillaries and expansion of sinusoidal space. Concomitant to this vascular remodeling, there was a transient depletion of hematopoietic activity in the marrow, which was compensated by an increase in mobilization and recruitment of HSCs and CEPs to the spleen resulting in splenomegaly. Neutralizing monoclonal antibody to VEGFR2 completely inhibited VEGF(165), but not Ang-1-induced mobilization and splenomegaly. These data suggest that temporal and regional activation of VEGF/VEGFR2 and Ang-1/Tie-2 signaling pathways are critical for mobilization and recruitment of HSCs and CEPs and may play a role in the physiology of postnatal angiogenesis and hematopoiesis.


Assuntos
Fatores de Crescimento Endotelial/fisiologia , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Linfocinas/fisiologia , Glicoproteínas de Membrana/fisiologia , Proteínas Proto-Oncogênicas , Transdução de Sinais/fisiologia , Adenoviridae , Angiopoietina-1 , Animais , Células da Medula Óssea , Fatores de Crescimento Endotelial/administração & dosagem , Fatores de Crescimento Endotelial/sangue , Fatores de Crescimento Endotelial/metabolismo , Feminino , Vetores Genéticos , Mobilização de Células-Tronco Hematopoéticas , Leucócitos/fisiologia , Linfocinas/administração & dosagem , Linfocinas/sangue , Linfocinas/metabolismo , Masculino , Glicoproteínas de Membrana/administração & dosagem , Glicoproteínas de Membrana/sangue , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos SCID , Proteínas de Neoplasias/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular , Baço/citologia , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
14.
J Perinat Med ; 29(1): 77-80, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11234621

RESUMO

Options for the treatment of thoracoabdominally conjoined twins are dependent on the anatomy of the cardiovascular system. It is important to increase the accuracy of diagnosis of conjoined twins with a fused heart. Color Doppler imaging performed in a 23-year-old nulliparous Japanese woman at 12 weeks of gestation revealed synchronized blood flow in 2 aortic arches arising from a single heart. The patient underwent a therapeutic abortion, and the diagnosis of conjoined twins with a fused heart was confirmed. Thus, color Doppler imaging is useful for investigating the cardiovascular anatomy in conjoined twins suspected of having a fused heart, even in an early gestational age.


Assuntos
Abdome , Sistema Cardiovascular/diagnóstico por imagem , Sistema Cardiovascular/embriologia , Tórax , Gêmeos Unidos , Ultrassonografia Pré-Natal , Adulto , Feminino , Coração , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Ultrassonografia Doppler em Cores
15.
Cancer Res ; 61(3): 1144-53, 2001 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-11221845

RESUMO

DNA methylation is the only known mechanism for an epigenetic genomic DNA modification that is capable of altering gene expression. A recent study reveals that the pattern of CpG island methylation is largely characteristic of tumor type, suggesting that distinct sets of genes are inactivated by methylation during development of each tumor type. We compared previously the methylation status between normal liver and liver tumors in SV40 T/t antigen transgenic mice (MT-D2 mice) using Restriction Landmark Genomic Scanning for Methylation (RLGS-M) and identified several loci/spots that appeared to be methylated frequently in liver tumors. One of these spots, B236, identified a locus on chromosome 12 (D12Ncvs7) syntenic with human 14q12-q21 that is frequently lost in certain human cancers. Shotgun sequencing of a bacterial artificial chro mosome clone containing this spot/locus was performed to identify genes within this region. The Genescan program predicted an open reading frame of a novel, intron-less gene adjacent to the B236 spot that encodes a putative 493-amino acid protein containing the SNAG repressor motif in the NH2-terminal region and five C2H2-type zinc finger motifs in the COOH-terminal half. This putative gene, methylated in liver tumor (mlt 1), is a novel member of the SNAG transcriptional repressor family with 43% amino acid identity to insulinoma-associated protein 1. An open reading frame encoding a protein quite similar to mouse mlt 1 (56% amino acid identity) was located in the syntenic region of the human genome, indi cating that mlt 1 is evolutionarily conserved in human. Northern blot analysis revealed that mlt 1 is normally expressed in brain, spleen, stom ach, and liver. However, mlt 1 expression was silenced in the liver tumors of MT-D2 mice. The putative promoter region of mlt 1 is unmethylated in normal tissues but methylated in all liver tumors from 11 MT-D2 mice We also found that mlt 1 was methylated and not expressed in N18TG-22 cells, a mouse neuroblastoma cell line. Treatment of N18TG-2 cells with a demethylating agent, 5-aza-deoxycytidine, resulted in an expression of mlt 1, indicating that the repression of mlt 1 is attributable to methylation Thus, mlt 1 is a novel target gene that is silenced by methylation during liver tumorigenesis initiated by SV40 T antigen.


Assuntos
Antígenos Transformantes de Poliomavirus/genética , Azacitidina/análogos & derivados , Metilação de DNA , Inativação Gênica , Neoplasias Hepáticas Experimentais/genética , Proteínas Repressoras/genética , Dedos de Zinco/genética , Sequência de Aminoácidos , Animais , Antimetabólitos Antineoplásicos/farmacologia , Azacitidina/farmacologia , Sequência de Bases , Proteínas de Ligação a DNA/genética , Decitabina , Feminino , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Humanos , Neoplasias Hepáticas Experimentais/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Dados de Sequência Molecular , Neuroblastoma/genética , Fases de Leitura Aberta , Regiões Promotoras Genéticas , RNA Mensageiro/genética , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genética
16.
Eur J Pediatr ; 159(12): 908-11, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11131350

RESUMO

UNLABELLED: We investigated the clinical and biochemical characteristics of a 6-year-old Japanese boy with very-long-chain acyl-CoA dehydrogenase (VLCAD) deficiency. He had hypoketotic hypoglycaemia, exercise- and fasting-induced lethargy, hepatomegaly and cardiomegaly. Significant laboratory findings included elevated plasma levels of creatine phosphokinase and acyl-carnitine and a fatty liver at biopsy suggesting a diagnosis of VLCAD deficiency. CONCLUSION: The diagnosis of very long-chain acyl-CoA dehydrogenase deficiency was supported by the results of acyl-CoA dehydrogenase activity for C8 and C16 fatty acids in skin fibroblasts from the patient. Treatment with medium chain triglycerides and L-carnitine in the diet improved his hepatomegaly and cardiomegaly.


Assuntos
Acil-CoA Desidrogenase de Cadeia Longa/deficiência , Erros Inatos do Metabolismo/diagnóstico , Cardiomegalia/complicações , Carnitina/uso terapêutico , Criança , Fígado Gorduroso/complicações , Fígado Gorduroso/diagnóstico , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico , Hepatomegalia/complicações , Humanos , Masculino , Erros Inatos do Metabolismo/complicações , Erros Inatos do Metabolismo/enzimologia , Erros Inatos do Metabolismo/terapia
17.
Ultrasound Obstet Gynecol ; 16(2): 171-8, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11117089

RESUMO

OBJECTIVES: To develop a new quantitative index, the notch depth index (NDI), to evaluate its association with the risk of pre-eclampsia and a small-for-gestational-age (SGA) infant and to compare its clinical usefulness with that of the uterine artery resistance index (RI) and the peak systolic to early diastolic velocity (A/C) ratio. METHODS: Uterine artery color Doppler ultrasound was performed in 288 consecutive healthy pregnant women at 20.2 +/- 2.0 (range 16.0-23.9) weeks of gestation. The NDI represents the depth of the early diastolic notch divided by the maximal diastolic velocity. RESULTS: Nine (3.1%) of the 288 women developed pre-eclampsia and 18 women (6.3%) delivered an SGA infant. The NDI was associated with subsequent onset of pre-eclampsia. The optimal cutoff value for the NDI in predicting pre-eclampsia was 0.14, giving a sensitivity, specificity and a positive predictive value (PPV) of 67, 92, and 22%, respectively. The PPV of the NDI was the largest of the three indices evaluated (12% for the RI and 16% for the A/C ratio). The relative risk for pre-eclampsia in women with values equal to or greater than the optimal cutoff values of the RI, A/C ratio and the NDI was 9.7 (95% confidence interval, 2.5-3.7), 19.2 (4.2-91), and 19.2 (5.1-71), respectively. The NDI of 0.14 improved the PPV of 18% determined by the presence of notches in bilateral uterine arteries. The optimal cutoff value of 0.14 for the NDI in predicting an SGA infant yielded a higher PPV (22%) than those for the RI (9%) and A/C ratio (12%). CONCLUSIONS: The NDI value in the second trimester is associated with the later onset of pre-eclampsia, and is clinically more useful in predicting pre-eclampsia than the two conventional indices.


Assuntos
Recém-Nascido Pequeno para a Idade Gestacional , Pré-Eclâmpsia/diagnóstico por imagem , Pré-Eclâmpsia/fisiopatologia , Ultrassonografia Doppler em Cores/métodos , Ultrassonografia Pré-Natal/métodos , Útero/irrigação sanguínea , Adulto , Artérias/diagnóstico por imagem , Artérias/fisiopatologia , Velocidade do Fluxo Sanguíneo/fisiologia , Diástole , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Pré-Eclâmpsia/diagnóstico , Valor Preditivo dos Testes , Gravidez , Probabilidade , Curva ROC , Medição de Risco , Fatores de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Útero/diagnóstico por imagem
18.
Auris Nasus Larynx ; 27(4): 327-34, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10996491

RESUMO

OBJECTIVE: Objective of this study is to know how a frequency compression hearing aid with new concepts is beneficial for severe-to-profound hearing impairments. (2) METHODS: Clinical trials of this hearing aid were conducted for 11 severe-to-profound hearing impaired listeners. These 11 wore the frequency compression hearing aid in their daily life and reported subjectively on its performance. Speech recognition tests with five listeners and audio-visual short sentence recognition tests with three listeners were also conducted. This hearing aid can separately adjust the fundamental frequency from the spectral envelope of input speech and can adjust frequency response by use of a post-processing digital filter. (3) RESULTS: Five listeners out of these 11 came to prefer this hearing aid in their daily life and are still wearing it. The results of the speech recognition tests show that the speech recognition scores were not improved for all listeners and the results of the audio-visual short sentence recognition tests do that the audio-visual recognition scores were improved for two listeners. (4) CONCLUSION: There were some severe-to-profound hearing impaired listeners who preferred the frequency compression hearing aid finally. It is also suggested that the benefits of this hearing aid may be evaluated correctly using not only speech but also visual materials.


Assuntos
Auxiliares de Audição , Transtornos da Audição/fisiopatologia , Transtornos da Audição/terapia , Idoso , Idoso de 80 Anos ou mais , Recursos Audiovisuais , Feminino , Audição , Humanos , Masculino , Pessoa de Meia-Idade , Percepção da Fala , Gravação de Videoteipe
19.
Gan To Kagaku Ryoho ; 27(4): 585-91, 2000 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-10791001

RESUMO

We evaluated the feasibility of high-dose CEP (cyclophosphamide 750 mg/m2, epirubicin 90 mg/m2, cis-platinum 70 mg/m2) therapy, with granulocyte colony-stimulating factor support every 21 days, in 18 patients with advanced and recurrent ovarian cancer. Ten patients (56%) received 6 cycles of this regimen as planned. Toxicities more than grade 3/4 on' the WHO scale of neutropenia and thrombocytopenia were observed in all cases. Nausea, vomiting, mucositis, malaise, alopecia, hepatotoxicity, and fever were common adverse effects. The average relative dose intensity of cyclophosphamide, epirubicin, cis-platinum was 0.77, 0.77, 0.79 respectively, and each RDI decreased in the last two cycles. These data suggest that this regimen could be performed safely with careful consideration on hepatotoxicity and thrombocytopenia.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Cisplatino/administração & dosagem , Ciclofosfamida/administração & dosagem , Epirubicina/administração & dosagem , Neoplasias Ovarianas/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/efeitos adversos , Ciclofosfamida/efeitos adversos , Esquema de Medicação , Epirubicina/efeitos adversos , Feminino , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Humanos , Pessoa de Meia-Idade , Projetos Piloto
20.
Lupus ; 9(1): 74-7, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10713652

RESUMO

We report on a 23-year-old Japanese female with a 13-year history of systemic lupus erythematosus (SLE), and two episodes of deterioration followed by treatment with high dose prednisolone. Although she had been recently treated with prednisolone (12.5 mg daily), her liver function became worse in July 1998. Results of a liver biopsy revealed multi-focal hepatic cell death in a severe fatty liver, without any inflammatory cell invasion. The biopsy also showed a positive TUNEL (Tdt-catalysed DNA nick end labelling) reaction indicating apoptosis. Her liver function recovered rapidly following steroid pulse therapy. Serum soluble Fas ligand (sFasL) was found to be elevated to a concentration of 0.395 ng/ml at the time of liver damage, but was less than 0.03 ng/ml before liver damage and after prednisolone treatment. The liver damage in this case appeared to be involved with apoptosis induced by sFasL. Although hepatitis associated with SLE is rare, apoptosis directly related to elevated sFasL levels might cause this complication.


Assuntos
Apoptose , Hepatite/etiologia , Fígado/patologia , Lúpus Eritematoso Sistêmico/complicações , Adulto , Biópsia , Proteína Ligante Fas , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Hepatite/sangue , Hepatite/tratamento farmacológico , Hepatite/patologia , Humanos , Marcação In Situ das Extremidades Cortadas , Ligantes , Testes de Função Hepática , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/patologia , Glicoproteínas de Membrana/sangue , Prednisolona/administração & dosagem , Prednisolona/uso terapêutico , Receptor fas/sangue
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