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1.
Phys Rev Lett ; 130(17): 173001, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37172243

RESUMO

To test bound-state quantum electrodynamics (BSQED) in the strong-field regime, we have performed high precision x-ray spectroscopy of the 5g-4f and 5f- 4d transitions (BSQED contribution of 2.4 and 5.2 eV, respectively) of muonic neon atoms in the low-pressure gas phase without bound electrons. Muonic atoms have been recently proposed as an alternative to few-electron high-Z ions for BSQED tests by focusing on circular Rydberg states where nuclear contributions are negligibly small. We determined the 5g_{9/2}- 4f_{7/2} transition energy to be 6297.08±0.04(stat)±0.13(syst) eV using superconducting transition-edge sensor microcalorimeters (5.2-5.5 eV FWHM resolution), which agrees well with the most advanced BSQED theoretical prediction of 6297.26 eV.

2.
Phys Rev Lett ; 127(5): 053001, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34397250

RESUMO

We observed electronic K x rays emitted from muonic iron atoms using superconducting transition-edge sensor microcalorimeters. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic Kα and Kß x rays together with the hypersatellite K^{h}α x rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the L-shell electrons, accompanied by electron side feeding. Assisted by a simulation, these data clearly reveal the electronic K- and L-shell hole production and their temporal evolution on the 10-20 fs scale during the muon cascade process.

3.
Phys Rev Lett ; 116(5): 056802, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26894727

RESUMO

In scanning tunneling microscopy, orbital selectivity of the tunneling process can make the topographic image dependent on a tip-surface distance. We have found reproducible dependence of the images on the distance for a monatomic layer of iron nitride formed on a Cu(001) surface. Observed atomic images systematically change between a regular dot array and a dimerized structure depending on the tip-surface distance, which turns out to be the only relevant parameter in the image variation. An accompanied change in the weight of Fe-3d local density of states to a tunneling background was detected in dI/dV spectra. These have been attributed to a shift in surface orbitals detected by the tip from the d states to the s/p states with increasing the tip-surface distance, consistent with an orbital assignment from first-principles calculations.

4.
Phys Rev Lett ; 114(8): 086401, 2015 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-25768771

RESUMO

We report electrical resistivity, ac magnetic susceptibility, and x-ray absorption spectroscopy measurements of intermediate valence YbNi_{3}Ga_{9} under pressure and magnetic field. We have revealed a characteristic pressure-induced Yb valence crossover within the temperature-pressure phase diagram, and a first-order metamagnetic transition is found below P_{c}∼9 GPa where the system undergoes a pressure-induced antiferromagnetic transition. As a possible origin of the metamagnetic behavior, a critical valence fluctuation emerging near the critical point of the first-order valence transition is discussed on the basis of the temperature-field-pressure phase diagram.

5.
Br J Cancer ; 110(12): 2965-74, 2014 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-24867687

RESUMO

BACKGROUND: Although T-cell immunity is thought to be involved in the prognosis of epithelial ovarian cancer (EOC) patients, immunosuppressive conditions hamper antitumour immune responses. Thus, their mechanisms and overcoming strategies need to be investigated. METHODS: The role of NF-κB in human EOC cells and macrophages was evaluated by in vitro production of immunosuppressive IL-6 and IL-8 by EOC cells and in vivo analysis of immune responses in nude mice implanted with human EOC cells using an NF-κB inhibitor DHMEQ. RESULTS: In EOC patients, increased plasma IL-6, IL-8, and arginase were observed. The NF-κB inhibitor DHMEQ inhibited the production of IL-6 and IL-8 by EOC cell lines. Immunosuppression of human DCs and macrophages by culture supernatant of EOC cells was reversed with the pretreatment of DHMEQ. Administration of DHMEQ to nude mice implanted with human EOC resulted in the restoration of T-cell stimulatory activity of murine DCs along with the reduction of tumour accumulation and arginase expression of MDSCs. Nuclear factor-κB inhibition in tumour-bearing mice also enhanced antitumour effects of transferred murine naive T cells. CONCLUSIONS: NF-κB is involved in the immunosuppression induced by human EOC, and its inhibitor may restore antitumour immune responses, indicating that NF-κB is an attractive target for EOC treatment.


Assuntos
Tolerância Imunológica , Interleucina-6/imunologia , Interleucina-8/imunologia , Neoplasias Epiteliais e Glandulares/imunologia , Neoplasias Ovarianas/imunologia , Fator de Transcrição RelA/imunologia , Transferência Adotiva , Animais , Arginase/sangue , Benzamidas/farmacologia , Carcinoma Epitelial do Ovário , Linhagem Celular Tumoral , Meios de Cultivo Condicionados/farmacologia , Cicloexanonas/farmacologia , Células Dendríticas/imunologia , Feminino , Humanos , Interleucina-6/biossíntese , Interleucina-6/sangue , Interleucina-8/biossíntese , Interleucina-8/sangue , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Transdução de Sinais/imunologia , Fator de Transcrição RelA/antagonistas & inibidores , Fator de Transcrição RelA/genética , Transplante Heterólogo
7.
Neuropathol Appl Neurobiol ; 38(6): 559-71, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22013984

RESUMO

AIMS: Multiple system atrophy (MSA) is pathologically characterized by the formation of α-synuclein-containing glial cytoplasmic inclusions (GCIs) in oligodendrocytes. However, the mechanisms of GCI formation are not fully understood. Cellular machinery for the formation of aggresomes has been linked to the biogenesis of the Lewy body, a characteristic α-synuclein-containing inclusion of Parkinson's disease and dementia with Lewy bodies. Here, we examined whether GCIs contain the components of aggresomes by immunohistochemistry. METHODS: Sections from five patients with MSA were stained immunohistochemically with antibodies against aggresome-related proteins and analysed in comparison with sections from five patients with no neurological disease. We evaluated the presence or absence of aggresome-related proteins in GCIs by double immunofluorescence and immunoelectron microscopy. RESULTS: GCIs were clearly immunolabelled with antibodies against aggresome-related proteins, such as γ-tubulin, histone deacetylase 6 (HDAC6) and 20S proteasome subunits. Neuronal cytoplasmic inclusions (NCIs) were also immunopositive for these aggresome-related proteins. Double immunofluorescence staining and quantitative analysis demonstrated that the majority of GCIs contained these proteins, as well as other aggresome-related proteins, such as Hsp70, Hsp90 and 62-kDa protein/sequestosome 1 (p62/SQSTM1). Immunoelectron microscopy demonstrated immunoreactivities for γ-tubulin and HDAC6 along the fibrils comprising GCIs. CONCLUSIONS: Our results indicate that GCIs, and probably NCIs, share at least some characteristics with aggresomes in terms of their protein components. Therefore, GCIs and NCIs may be another manifestation of aggresome-related inclusion bodies observed in neurodegenerative diseases.


Assuntos
Encéfalo/metabolismo , Corpos de Inclusão/metabolismo , Atrofia de Múltiplos Sistemas/metabolismo , Neuroglia/metabolismo , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Feminino , Desacetilase 6 de Histona , Histona Desacetilases/metabolismo , Humanos , Corpos de Inclusão/patologia , Corpos de Lewy/metabolismo , Corpos de Lewy/patologia , Masculino , Pessoa de Meia-Idade , Atrofia de Múltiplos Sistemas/patologia , Neuroglia/patologia , Neurônios/metabolismo , Neurônios/patologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Tubulina (Proteína)/metabolismo
8.
Eur J Neurol ; 19(5): 681-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22136555

RESUMO

BACKGROUND: Nearly all epidemiologic studies examining the association between the risk of Parkinson's disease (PD) and diet have focused on single foods and specific nutrients. However, epidemiologic evidence for the association of dietary pattern with PD, namely the measurement of overall diet by considering the cumulative effects of nutrients is extremely limited. We conducted a hospital-based case-control study in Japan to examine the relationship between dietary patterns and the risk of PD. METHODS: Patients with PD diagnosed using the UK PD Society Brain Bank criteria (n = 249) and controls without neurodegenerative diseases (n = 368) were recruited. At the time of recruitment, dietary intake during the preceding 1 month was assessed using a validated, self-administered diet history questionnaire. Dietary patterns from 33 predefined food groups (energy-adjusted food g/day) were extracted by factor analysis. RESULTS: Three dietary patterns were identified: 'Healthy', 'Western' and 'Light meal' patterns. After adjustment for potential non-dietary confounding factors, the Healthy pattern, characterized by a high intake of vegetables, seaweed, pulses, mushrooms, fruits and fish, was inversely associated with the risk of PD with a border-line significance (P for trend = 0.06). Multivariate Odds ratio (95% confidence intervals) for PD in the highest quartile of the Healthy pattern was 0.54 (0.32-0.92) compared with the lowest quartile. No associations with PD were detected for the other two dietary patterns. CONCLUSION: In this case-control study in Japan, a dietary pattern consisting of high intakes of vegetables, fruits and fish may be associated with a decreased risk of PD.


Assuntos
Dieta , Doença de Parkinson/epidemiologia , Doença de Parkinson/etiologia , Idoso , Estudos de Casos e Controles , Dieta/efeitos adversos , Análise Fatorial , Comportamento Alimentar , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Fenômenos Fisiológicos da Nutrição , Doença de Parkinson/diagnóstico , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Inquéritos e Questionários
10.
Eur J Neurol ; 18(1): 106-13, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20491891

RESUMO

BACKGROUND: antioxidant vitamins are expected to protect cells from oxidative damage by neutralizing the effects of reactive oxygen species. However, epidemiological evidence regarding the associations between antioxidant vitamin intake and Parkinson's disease (PD) is limited and inconsistent. We investigated the relationship between dietary intake of selected antioxidant vitamins, vegetables and fruit and the risk of PD in Japan using data from a multicenter hospital-based case-control study. METHODS: included were 249 patients within 6 years of onset of PD. Controls were 368 inpatients and outpatients without a neurodegenerative disease. Information on dietary factors was collected using a validated self-administered diet history questionnaire. Adjustment was made for sex, age, region of residence, pack-years of smoking, years of education, body mass index, dietary intake of cholesterol, alcohol, total dairy products, and coffee and the dietary glycemic index. RESULTS: higher consumption of vitamin E and ß-carotene was significantly associated with a reduced risk of PD after adjustment for confounders under study: the adjusted odds ratio in the highest quartile was 0.45 (95% confidence interval [CI]: 0.25-0.79, P for trend = 0.009) for vitamin E and 0.56 (95% CI: 0.33-0.97, P for trend = 0.03) for ß-carotene. Stratified by sex, such inverse associations were significant only in women. No material relationships were shown between intake of vitamin C, α-carotene, cryptoxanthin, green and yellow vegetables, other vegetables, or fruit and the risk of PD. CONCLUSIONS: higher intake of vitamin E and ß-carotene may be associated with a decreased risk of PD.


Assuntos
Antioxidantes/administração & dosagem , Dieta , Doença de Parkinson/etiologia , Risco , Vitamina E/administração & dosagem , beta Caroteno/administração & dosagem , Idoso , Estudos de Casos e Controles , Inquéritos sobre Dietas , Feminino , Humanos , Japão , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Inquéritos e Questionários , Verduras
11.
Infect Prev Pract ; 3(3): 100151, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34647007

RESUMO

BACKGROUND: Periodic point prevalence surveys (PPSs) provide a method for assessing changes in healthcare-associated infections (HAIs) and antimicrobial use over time. Following the introduction of an antimicrobial stewardship programme at Nagoya University Hospital (Aichi, Japan) a five-year PPS study was performed to highlight any epidemiological changes. METHODS: One-day PPSs were performed annually in July at Nagoya University Hospital. Data on patient characteristics, medical devices, active HAIs and antimicrobial use were collected using a standard data-collection form. RESULTS: A total of 4339 patients were included. Over the five-year study period the median patient age was 62 years, median duration of hospital admission was nine days, 9% of patients had an HAI and 35.2% received at least one antimicrobial. Overall there were 406 HAIs (95% confidence interval, 369-447) with surgical site infection, pneumonia and febrile neutropenia occurring most frequently. Enterobacterales were the most common pathogens (N = 78, 28.6%) and 32.1% were third-generation cephalosporin-resistant. Meropenem was the most frequently prescribed antimicrobial for HAIs. Surgical antimicrobial prophylaxis changed drastically, with shorter durations and a marked reduction in oral cephalosporin use. However, antimicrobials for medical prophylaxis gradually increased. CONCLUSIONS: This five-year PPS study shows consistent data for patient background, HAIs and causative pathogens and highlights changes in antimicrobial use during the era of the National Action Plan on Antimicrobial Resistance. To describe the epidemiology of Japanese hospitals by PPS, multicentre PPSs including in community hospitals should be performed annually.

12.
J Neurol Neurosurg Psychiatry ; 81(1): 94-6, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20019224

RESUMO

BACKGROUND: Hereditary neuralgic amyotrophy (HNA), also known as hereditary brachial plexus neuropathy, has phenotypic and genetic heterogeneity. Mutations in the septin 9 (SEPT9) gene were recently identified in some HNA patients. The phenotypic spectrum of HNA caused by SEPT9 mutations is not well known. OBJECTIVE: To characterise the phenotype of a large family of HNA patients with the SEPT9 R88W mutation. METHODS: We report clinical, electrophysiological, neuroimaging and genetic findings of six HNA patients from a Japanese family. RESULTS: All 17 neuropathic episodes identified were selectively and asymmetrically distributed in the upper-limb nerves. Severe pain was an initial symptom in 16 episodes (94%). Motor weakness occurred in 15 (88%) and sensory signs in 10 (59%). A minor dysmorphism, hypotelorism, was seen in all. Nerve conduction studies revealed focal demyelination as well as prominent axonal degeneration changes. Needle electromyography revealed chronic neurogenic patterns only in the upper limbs. An MRI study showed a gadolinium-enhanced brachial plexus. The missense mutation c.262C>T; p.R88W was found in exon 2 of SEPT9 in all patients. CONCLUSIONS: The SEPT9 R88W mutation in this family causes selective involvement of the brachial plexus and upper-limb nerves. Wider and more universal recognition of clinical hallmarks and genetic counselling are of diagnostic importance for HNA caused by the SEPT9 mutation.


Assuntos
Neurite do Plexo Braquial/genética , Proteínas do Citoesqueleto/genética , Proteínas de Ligação ao GTP/genética , Mutação de Sentido Incorreto/genética , Adolescente , Adulto , Idoso , Braço/inervação , Plexo Braquial/patologia , Criança , Família , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Debilidade Muscular/genética , Linhagem , Fenótipo , Septinas , Adulto Jovem
13.
Acta Neurol Scand ; 122(6): 377-82, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20175761

RESUMO

OBJECTIVE: To assess the association between active and passive smoking and the risk of Parkinson's disease (PD), a case-control study with 249 PD patients and 369 controls was carried out in Japan. METHODS: Information on smoking was obtained through a self-administered questionnaire. Adjustment was made for age, sex, region of residence, educational level, and occupational exposure. RESULTS: Ever having smoked cigarettes was associated with a reduced risk of PD [adjusted odds ratio = 0.38; 95% confidence interval (CI): 0.24-0.59]. Risk for former smokers was intermediate between the high risk for never smokers and the low risk for current smokers. Adjusted odds ratios for former and current smokers were 0.51 (95% CI: 0.32-0.82) and 0.12 (95% CI: 0.05-0.26), respectively. There was an inverse dose-response gradient with pack-years smoked. No significant association was detected for passive smoking exposure. CONCLUSION: Our results appear to confirm data from previous epidemiological studies.


Assuntos
Doença de Parkinson/etiologia , Poluição por Fumaça de Tabaco/efeitos adversos , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Japão/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Doença de Parkinson/epidemiologia , Fatores de Risco , Inquéritos e Questionários , Poluição por Fumaça de Tabaco/estatística & dados numéricos
14.
J Phys Condens Matter ; 21(1): 016002, 2009 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21817239

RESUMO

The proper annealing of Ni(51)Mn(28)Ga(21) ribbon alloy gives rise to an increase of the saturation magnetization and of the magnetic order T(C) (up to 20 K) and martensitic transition T(M) (up to 10 K) temperatures. The combined x-ray absorption spectroscopy (XAS) and x-ray magnetic circular dichroism (XMCD) studies indicate that the annealing treatment drives the alloy to a more ordered structure without significantly affecting the local structure in terms of interatomic distances and bonding geometry. By contrast, the annealing strongly affects the near-edge absorption at the Mn K-edge while no effect is observed at either the Ni or Ga K-edge. These results suggest that annealing leads to a modification of the electronic structure of the Mn atoms while that of Ni and Ga atoms remains unvaried. However, strong XMCD signals are detected at both Ni and Ga K-edges whose amplitude increases after annealing. These results point out that despite the change of the magnetic properties of the system being mainly associated with the modification of the electronic properties of the Mn atoms, both Ni and Ga may play a non-negligible role through the polarization of the conduction band.

15.
Leukemia ; 21(2): 288-96, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17183364

RESUMO

Hypercalcemia is relatively rare but clinically important complication in childhood leukemic patients. To clarify the clinical characteristics, mechanisms of hypercalcemia, response to management for hypercalcemia, incidence of t(17;19) and final outcome of childhood acute lymphoblastic leukemia (ALL) accompanied by hypercalcemia, clinical data of 22 cases of childhood ALL accompanied by hypercalcemia (>12 mg/dl) reported in Japan from 1990 to 2005 were retrospectively analyzed. Eleven patients were 10 years and older. Twenty patients had low white blood cell count (<20 x 10(9)/l), 15 showed hemoglobin> or =8 g/dl and 14 showed platelet count > or =100 x 10(9)/l. Parathyroid hormone-related peptide (PTHrP)-mediated hypercalcemia was confirmed in 11 of the 16 patients in whom elevated-serum level or positive immunohistochemistry of PTHrP was observed. Hypercalcemia and accompanying renal insufficiency resolved quickly, particularly in patients treated with bisphosphonate. t(17;19) or add(19)(p13) was detected in five patients among 17 patients in whom karyotypic data were available, and the presence of E2A-HLF was confirmed in these five patients. All five patients with t(17;19)-ALL relapsed very early. Excluding the t(17;19)-ALL patients, the final outcome of ALL accompanied by hypercalcemia was similar to that of all childhood ALL patients, indicating that the development of hypercalcemia itself is not a poor prognostic factor.


Assuntos
Cromossomos Humanos Par 17 , Cromossomos Humanos Par 19 , Proteínas de Ligação a DNA/genética , Hipercalcemia/complicações , Hipercalcemia/genética , Proteínas de Fusão Oncogênica/genética , Proteína Relacionada ao Hormônio Paratireóideo/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Fatores de Transcrição/genética , Translocação Genética , Adolescente , Cálcio/sangue , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Rev Sci Instrum ; 79(5): 053502, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18513064

RESUMO

A negative muon in hydrogen targets, e.g., D2 or D-T mixture, can catalyze nuclear fusions following a series of atomic processes involving muonic hydrogen molecular formation (muon-catalyzed fusion, muCF). The ortho-para state of D2 is a crucial parameter not only for enhancing the fusion rate but also to precisely investigate various muonic atom processes. We have developed a system for controlling and measuring the ortho-para ratio of D2 gas for muCF experiments. We successfully collected para-enriched D2 without using liquid-hydrogen coolant. Ortho-enriched D2 was also obtained by using a catalytic conversion method with a mixture of chromium oxide and alumina. The ortho-para ratio of D2 gas was measured with a compact Raman spectroscopy system. We produced large volume (5-30 l at STP), high-purity (less than ppm high-Z contaminant) D2 targets with a wide range of ortho-para ratios (ortho 20%-99%). By using the ortho-para controlled D2 in muCF experiments, we observed the dependence of muCF phenomena on the ortho-para ratio.

17.
J Clin Invest ; 78(5): 1331-8, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3490495

RESUMO

Production of B cell growth factor (BCGF) from B-chronic lymphocytic leukemia (B-CLL) cells was demonstrated. Freshly isolated monoclonal B-CLL cells expressed surface mu, delta, B1, and Leu 1, but not Ba (an antigen expressed only on activated B cells). Upon stimulation with anti-IgM, they secreted BCGF, which could act on anti-IgM-stimulated autologous leukemic cells as well as anti-IgM-stimulated normal B cells. Cell lines established from these leukemic cells also constitutively secreted BCGF. The BCGF from B-CLL cells or established cell lines induced neither proliferation nor enhanced HLA-DR expression in resting B cells. These results show the presence of B cell-derived BCGF, which is distinct from BSF-1 and effective only on activated B cells. They also suggest that an autocrine mechanism may operate in the growth of B-CLL cells.


Assuntos
Linfócitos B/imunologia , Substâncias de Crescimento/biossíntese , Leucemia Linfoide/imunologia , Linfocinas/biossíntese , Antígenos de Superfície/análise , Linfócitos B/citologia , Divisão Celular , Linhagem Celular , Células Cultivadas , DNA/isolamento & purificação , Humanos , Interleucina-1/análise , Interleucina-2/análise , Interleucina-4 , Monócitos/citologia , Monócitos/imunologia , Tonsila Palatina
18.
J Clin Invest ; 78(6): 1439-42, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3097073

RESUMO

We describe a 10-yr-old boy with T-lineage non-Hodgkin's lymphoma. He had a mediastinal mass, swollen supraclavicular lymph nodes, and pleural effusion. A supraclavicular lymph node biopsy under light microscopy showed a malignant lymphoma of diffuse lymphoblastic type. Most of the cells taken from the malignant pleural effusion expressed T cell-associated antigens such as Leu-1 and OKT 8. To confirm these antigens as T-lineage lymphoma, we examined genomic DNA from malignant cells obtained from the pleural effusion. As was expected, T cell receptor beta-chain gene rearrangements were demonstrated. However, when the immunoglobulin gene organization was analyzed, we detected rearrangements in both the heavy- and kappa-chain genes. To our knowledge, this is the first case in which kappa-chain gene rearrangement was detected in apparent T-lineage cells. These findings provide important information relating to determination of the cellular lineage of lymphoid malignancy.


Assuntos
Cadeias kappa de Imunoglobulina/genética , Linfoma/imunologia , Recombinação Genética , Criança , DNA/análise , Humanos , Linfoma/genética , Masculino , RNA Mensageiro/análise , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T
19.
J Clin Invest ; 102(4): 853-60, 1998 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9710455

RESUMO

The present study analyzed peripheral blood B cell populations separated by IgD and CD27 expression in six males with X-linked hyper-IgM syndrome (XHIM). Costimulation of mononuclear cells from most of the patients induced no to low levels of class switching from IgM to IgG and IgA with Staphylococcus aureus Cowan strain (SAC) plus IL-2 or anti-CD40 mAb (anti-CD40) plus IL-10. Measurable levels of IgE were secreted in some of the patients after stimulation with anti-CD40 plus IL-4. Costimulation with SAC plus IL-2 plus anti-CD40 plus IL-10 yielded secretion of significant levels of IgG in addition to IgM, but not IgA. The most striking finding was that peripheral blood B cells from all of the six patients were composed of only IgD+ CD27(-) and IgD+ CD27(+) B cells; IgD- CD27(+) memory B cells were greatly decreased. IgD+ CD27(+) B cells from an XHIM patient produced IgM predominantly. Our data indicate that the low response of IgG production in XHIM patients is due to reduced numbers of IgD- CD27(+) memory B cells. However, the IgG production can be induced by stimulation of immunoglobulin receptors and CD40 in cooperation with such cytokines as IL-2 and IL-10 in vitro.


Assuntos
Subpopulações de Linfócitos B/imunologia , Hipergamaglobulinemia/imunologia , Imunoglobulina D/deficiência , Imunoglobulina M/biossíntese , Memória Imunológica , Aberrações dos Cromossomos Sexuais/imunologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/análise , Cromossomo X , Adolescente , Adulto , Antígenos CD40/imunologia , Ligante de CD40 , Criança , Ligação Genética , Humanos , Hipergamaglobulinemia/genética , Imunoglobulinas/biossíntese , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/imunologia , Transdução de Sinais , Síndrome
20.
Neuroscience ; 141(2): 917-927, 2006 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-16716527

RESUMO

Leukotriene B4 is a potent lipid mediator, which has been identified as a potent proinflammatory and immunomodulatory compound. Although there has been robust evidence indicating that leukotriene B4 is synthesized in the normal brain, detailed distribution and its functions in the nervous system have been unclear. To obtain insight into the possible neural function of leukotriene B4, we examined the immunohistochemical distribution of leukotriene A4 hydrolase, an enzyme catalyzing the final and committed step in leukotriene B4 biosynthesis, in the mouse nervous system. Immunoreactivity for leukotriene A4 hydrolase showed widespread distribution with preference to the sensory-associated structures; i.e. neurons in the olfactory epithelium and vomeronasal organ, olfactory glomeruli, possibly amacrine cells, neurons in the ganglion cell layer and three bands in the inner plexiform layer of the retina, axons in the optic nerve and tract up to the superior colliculus, inner and outer hair cells and the spiral ganglion cells in the cochlea, vestibulocochlear nerve bundle, spinal trigeminal tract, and lamina II of the spinal cord. Double immunofluorescence staining demonstrated that most of the leukotriene A4-hydrolase-immunopositive neurons coexpressed calretinin, a calcium-binding protein in neurons. The ubiquitous distribution of leukotriene A4 hydrolase was in sharp contrast with the distribution of leukotriene C4 synthase [Shimada A, Satoh M, Chiba Y, Saitoh Y, Kawamura N, Keino H, Hosokawa M, Shimizu T (2005) Highly selective localization of leukotriene C4 synthase in hypothalamic and extrahypothalamic vasopressin systems of mouse brain. Neuroscience 131:683-689] which was confined to the hypothalamic and extrahypothalamic vasopressinergic neurons. These results suggest that leukotriene B4 may exert some neuromodulatory function mainly in the sensory nervous system, in concert with calretinin.


Assuntos
Epóxido Hidrolases/metabolismo , Sistema Nervoso/metabolismo , Proteína G de Ligação ao Cálcio S100/metabolismo , Animais , Calbindina 2 , Imuno-Histoquímica/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sistema Nervoso/citologia , Sistema Nervoso/enzimologia
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