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4.
Phys Rev Lett ; 124(6): 065101, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32109113

RESUMO

The first-order Fermi acceleration of electrons requires an injection of electrons into a mildly relativistic energy range. However, the mechanism of injection has remained a puzzle both in theory and observation. We present direct evidence for a novel stochastic shock drift acceleration theory for the injection obtained with Magnetospheric Multiscale observations at the Earth's bow shock. The theoretical model can explain electron acceleration to mildly relativistic energies at high-speed astrophysical shocks, which may provide a solution to the long-standing issue of electron injection.

5.
Phys Rev Lett ; 123(23): 235101, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31868466

RESUMO

A 3D fully kinetic simulation shows that the lower-hybrid drift instability disturbs the front of magnetic reconnection outflow jets and additionally causes energy dissipation. The result is very consistent with a disturbance observed at the dipolarization front (DF) in Earth's magnetotail by the Magnetospheric Multiscale (MMS) mission. A fully kinetic dispersion relation solver, validated by the MMS observations, further predicts that the disturbance of the reconnection jet front could occur over different parameter regimes in space plasmas including Earth's DF and solar flares.

6.
J Eur Acad Dermatol Venereol ; 33(11): 2050-2057, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31301194

RESUMO

Although many variations of guidelines have been released, there is limited research that compares multiple treatment strategies for basal cell carcinoma (BCC). The aim of this study was to systematically review the studies reporting on multiple treatments for BCC with systematic review and network meta-analyses. Search formulas for databases, such as PubMed, EMBASE, Web of Science Core Collection and Cochrane Central Register of Controlled Trials, were created with the support of Cochrane Japan. The patient-level and tumour-level meta-analyses were performed for both the long-term treatment-failure and treatment-success. Of the 1464 studies identified from the database and hand searches, 14 met our inclusion criteria. These 14 studies included 2524 patients and 1738 tumours. Our study indicated that the incidence of treatment-failure of invasive treatments such as surgery and Mohs micrographic surgery was significantly lower than that of superficial therapies such as cryotherapy, photodynamic therapy, radiotherapy or topical therapies, in the patient-level and the tumour-level analyses, despite histological-type and pretreatment. Relapse of BCC may be a low life-threatening risk, and there are merits of non-surgical treatment. However, the significant difference in the recurrence rate is essential. Our study can provide useful guidance to clinicians in selecting treatment options for BCC.


Assuntos
Carcinoma Basocelular/terapia , Neoplasias Cutâneas/terapia , Humanos , Metanálise em Rede , Fatores de Tempo , Falha de Tratamento
7.
Nature ; 569(7757): E9, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31073227

RESUMO

Change history: In this Letter, the y-axis values in Fig. 3f should go from 4 to -8 (rather than from 4 to -4), the y-axis values in Fig. 3h should appear next to the major tick marks (rather than the minor ticks), and in Fig. 1b, the arrows at the top and bottom of the electron-scale current sheet were going in the wrong direction; these errors have been corrected online.

8.
Science ; 362(6421): 1391-1395, 2018 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-30442767

RESUMO

Magnetic reconnection is an energy conversion process that occurs in many astrophysical contexts including Earth's magnetosphere, where the process can be investigated in situ by spacecraft. On 11 July 2017, the four Magnetospheric Multiscale spacecraft encountered a reconnection site in Earth's magnetotail, where reconnection involves symmetric inflow conditions. The electron-scale plasma measurements revealed (i) super-Alfvénic electron jets reaching 15,000 kilometers per second; (ii) electron meandering motion and acceleration by the electric field, producing multiple crescent-shaped structures in the velocity distributions; and (iii) the spatial dimensions of the electron diffusion region with an aspect ratio of 0.1 to 0.2, consistent with fast reconnection. The well-structured multiple layers of electron populations indicate that the dominant electron dynamics are mostly laminar, despite the presence of turbulence near the reconnection site.

9.
Eur J Neurol ; 25(9): e108-e109, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30134052
11.
Nature ; 557(7704): 202-206, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29743689

RESUMO

Magnetic reconnection in current sheets is a magnetic-to-particle energy conversion process that is fundamental to many space and laboratory plasma systems. In the standard model of reconnection, this process occurs in a minuscule electron-scale diffusion region1,2. On larger scales, ions couple to the newly reconnected magnetic-field lines and are ejected away from the diffusion region in the form of bi-directional ion jets at the ion Alfvén speed3-5. Much of the energy conversion occurs in spatially extended ion exhausts downstream of the diffusion region 6 . In turbulent plasmas, which contain a large number of small-scale current sheets, reconnection has long been suggested to have a major role in the dissipation of turbulent energy at kinetic scales7-11. However, evidence for reconnection plasma jetting in small-scale turbulent plasmas has so far been lacking. Here we report observations made in Earth's turbulent magnetosheath region (downstream of the bow shock) of an electron-scale current sheet in which diverging bi-directional super-ion-Alfvénic electron jets, parallel electric fields and enhanced magnetic-to-particle energy conversion were detected. Contrary to the standard model of reconnection, the thin reconnecting current sheet was not embedded in a wider ion-scale current layer and no ion jets were detected. Observations of this and other similar, but unidirectional, electron jet events without signatures of ion reconnection reveal a form of reconnection that can drive turbulent energy transfer and dissipation in electron-scale current sheets without ion coupling.

12.
J Crohns Colitis ; 12(suppl_1): S329, 2018 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31135895

RESUMO

BACKGROUND: Oral mesalazine effectively induces and maintains remission in inflammatory bowel diseases (IBD) patients. However, adherence to the drug regimen is low. Shared decision-making (SDM) is considered effective in promoting treatment adherence in IBD patients. We used SDM to switch non-adherent IBD patients from oral mesalazine tablets to granules and checked the new adherence rates. METHODS: The IRB of our hospital approved this observational study named 'Evaluation of improvement of adherence by changing oral mesalazine to Pentasa granule in low adherent inflammatory bowel disease patients, IMPACT-PG'. We used the Morisky Medication Adherence Scale (MMAS-8, where an MMAS-8 score of ≥6 indicates good adherence) to assess adherence to oral mesalazine. We met with low adherence patients and explained the benefits and characteristics of mesalazine granules and tablets; we then gave them a choice between continuing with the same pH-dependent mesalazine tablets (with a 20% weight/volume decrease) and switching to oral mesalazine granules (2 g in one stick, 2 g once or twice a day). Primary endpoint was adherence rate in IBD patients with granule or with tablet at 6 months, and secondary endpoint was adherence rate at 12 months. Contributing factors to good adherence to the oral regimen were also examined. The adherence rate was analysed using chi-square test, and contributing factors were determined by multivariate analysis using SPSS ver24. RESULTS: One hundred and eighty-three patients (126 UC and 57 Crohn's colitis patients) were enrolled and examined adherence by MMAS-8 score. Good adherence ratio was 42.6% (78 of 183). Both higher age and low frequency of medication were significantly more common in adherent patients than in non-adherent patients. Odds ratios of age and the frequency of daily medication were 1.057 (95% CI 1.029-1.086; p < 0.0001) and 0.407 (95% CI 0.218-0.759; p = 0.005), respectively. SDM was performed to the 105 low adherence patients. 67% of the low adherence patients (70 of 105) preferred mesalazine granules. Five patients were dropped out until 6 months, as well as 13 patients were dropped out until 12 months. Remission rates at 0, 6, and 24 months were not significantly different between granule and tablet groups. Adherence rates at 6 [67% (44/66) vs. 32% (11 of 34)] and at 12 [72% (43 of 60) vs. 44% (14 of 32)] months were significantly higher in the granule group than in the tablet group. CONCLUSIONS: SDM was effective for switching patients from a mesalazine tablet to a granule regimen, and adherence rates were improved in IBD patients.

13.
Science ; 352(6290): aaf2939, 2016 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-27174677

RESUMO

Magnetic reconnection is a fundamental physical process in plasmas whereby stored magnetic energy is converted into heat and kinetic energy of charged particles. Reconnection occurs in many astrophysical plasma environments and in laboratory plasmas. Using measurements with very high time resolution, NASA's Magnetospheric Multiscale (MMS) mission has found direct evidence for electron demagnetization and acceleration at sites along the sunward boundary of Earth's magnetosphere where the interplanetary magnetic field reconnects with the terrestrial magnetic field. We have (i) observed the conversion of magnetic energy to particle energy; (ii) measured the electric field and current, which together cause the dissipation of magnetic energy; and (iii) identified the electron population that carries the current as a result of demagnetization and acceleration within the reconnection diffusion/dissipation region.

14.
Clin Genet ; 89(6): 739-43, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26830932

RESUMO

The p.Asp211Gly homozygous HYLS1 mutation is so far known to cause only hydrolethalus syndrome, a lethal malformation syndrome. We report living sibling patients with a homozygous no-stop mutation in exon 4 of HYLS1, NM_145014.2:c.900A>C (p.Ter300TyrextTer11) in the second decade of life. The proband has Joubert syndrome (JS). The younger brother also has JS and an enlarged posterior fossa that was initially diagnosed as Dandy-Walker malformation. The present mutation is unique as it affects the stop codon. The product protein HYLS1 plays an essential role in the formation of the primary cilium. This report provides insight into the spectrum of disorders involving midline brain defects closely related to cilium dysfunction or ciliopathy.


Assuntos
Anormalidades Múltiplas/genética , Cerebelo/anormalidades , Anormalidades do Olho , Predisposição Genética para Doença/genética , Mutação , Proteínas/genética , Retina/anormalidades , Anormalidades Múltiplas/diagnóstico por imagem , Adolescente , Sequência de Bases , Cerebelo/diagnóstico por imagem , Criança , Consanguinidade , Exoma/genética , Anormalidades do Olho/diagnóstico por imagem , Anormalidades do Olho/genética , Feminino , Homozigoto , Humanos , Doenças Renais Císticas/diagnóstico por imagem , Doenças Renais Císticas/genética , Masculino , Linhagem , Retina/diagnóstico por imagem , Análise de Sequência de DNA , Irmãos
15.
Br J Surg ; 103(4): 337-47, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26840944

RESUMO

BACKGROUND: Patients' quality of life (QoL) deteriorates remarkably after gastrectomy. Billroth I reconstruction following distal gastrectomy has the physiological advantage of allowing food to pass through the duodenum. It was hypothesized that Billroth I reconstruction would be superior to Roux-en-Y reconstruction in terms of long-term QoL after distal gastrectomy. This study compared two reconstructions in a multicentre prospective randomized clinical trial to identify the optimal reconstruction procedure. METHODS: Between January 2009 and September 2010, patients who underwent gastrectomy for gastric cancer were randomized during surgery to Billroth I or Roux-en-Y reconstruction. The primary endpoint was assessment of QoL using the Functional Assessment of Cancer Therapy - Gastric (FACT-Ga) questionnaire 36 months after surgery. RESULTS: A total of 122 patients were enrolled in the study, 60 to Billroth I and 62 to Roux-en-Y reconstruction. There were no differences between the two groups in terms of postoperative complications or mortality, and no significant differences in FACT-Ga total score (P = 0·496). Symptom scales such as epigastric fullness (heaviness), diarrhoea and fatigue were significantly better in the Billroth I group at 36 months after gastrectomy (heaviness, P = 0·040; diarrhoea, P = 0·046; fatigue, P = 0·029). The rate of weight loss in the third year was lower for patients in the Billroth I group (P = 0·046). CONCLUSION: The choice of anastomotic reconstruction after distal gastrectomy resulted in no difference in long-term QoL in patients with gastric cancer. REGISTRATION NUMBER: NCT01065688 (http://www.clinicaltrials.gov).


Assuntos
Anastomose em-Y de Roux/métodos , Gastrectomia/métodos , Gastroenterostomia/métodos , Qualidade de Vida , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose em-Y de Roux/psicologia , Feminino , Seguimentos , Gastrectomia/psicologia , Gastroenterostomia/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Procedimentos de Cirurgia Plástica/métodos , Neoplasias Gástricas/psicologia , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
16.
Phys Chem Chem Phys ; 17(43): 29057-63, 2015 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-26456398

RESUMO

The oxygen ionic conduction in ZrO2 systems under tensile epitaxial strain was investigated by performing ab initio molecular dynamics (MD) calculations based on density functional theory (DFT) to elucidate the essential factors in the colossal ionic conductivity observed in the yttria stabilized ZrO2 (YSZ)/SrTiO3 heterostructure. Three factors were evaluated: lattice strain, oxygen vacancies, and dopants. Phonon calculations based on density functional perturbation theory (DFPT) were used to obtain the most stable structure for nondoped ZrO2 under 7% tensile strain along the a- and b-axes. This structure has the space group Pbcn, which is entirely different from that of cubic ZrO2, suggesting that previous ab initio MD calculations assuming cubic ZrO2 may have overestimated the ionic conductivity due to relaxation from the initial structure to the stable structure (Pbcn). Our MD calculations revealed that the ionic conductivity is enhanced only when tensile strain and oxygen vacancies are incorporated, although the presently obtained diffusion constant is far below the range for the colossal ionic conduction experimentally observed. The enhanced ionic conductivity is due to the combined effects of oxygen sublattice formation induced by strain and deformation of this sublattice by oxygen vacancies.

17.
Neuroscience ; 284: 566-580, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25450958

RESUMO

The cerebral cortex is an indispensable region that is involved in higher cognitive function in the mammalian brain, and is particularly evolved in the primate brain. It has been demonstrated that cortical areas are formed by both innate and activity-dependent mechanisms. However, it remains unknown what molecular changes induce cortical expansion and complexity during primate evolution. Active DNA methylation/demethylation is one of the epigenetic mechanisms that can modify gene expression via the methylation/demethylation of promoter regions. Three growth arrest and DNA damage-inducible small nuclear proteins, Gadd45 alpha, beta, and gamma, have been identified as regulators of methylation status. To understand the involvement of epigenetic factors in primate cortical evolution, we started by analyzing expression of these demethylation genes in the developing common marmoset (Callithrix jacchus) and mouse (Mus musculus) brain. In the marmoset brain, we found that cortical expression levels of Gadd45 alpha and gamma were reduced during development, whereas there was high expression of Gadd45 beta in some areas of the adult brain, including the prefrontal, temporal, posterior parietal and insula cortices, which are particularly expanded in greater primates and humans. Compared to the marmoset brain, there were no clear regional differences and constant or reduced Gadd45 expression was seen between juvenile and adult mouse brain. Double staining with a neuronal marker revealed that most Gadd45-expressing cells were NeuN-positive neurons. Thus, these results suggest the possibility that differential Gadd45 expression affects neurons, contributing cortical evolution and diversity.


Assuntos
Callithrix/crescimento & desenvolvimento , Córtex Cerebral/crescimento & desenvolvimento , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos/crescimento & desenvolvimento , Animais , Antígenos de Diferenciação/metabolismo , Callithrix/metabolismo , Proteínas de Transporte/metabolismo , Contagem de Células , Proteínas de Ciclo Celular/metabolismo , Córtex Cerebral/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas de Ligação a DNA , Feminino , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Imuno-Histoquímica , Hibridização In Situ , Masculino , Camundongos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Proteínas Nucleares/metabolismo , Especificidade da Espécie , Proteínas GADD45
18.
J Oral Rehabil ; 41(10): 715-22, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24909970

RESUMO

Experimental loss of occlusal support caused by the extraction or grinding of molar teeth has been reported to foment the impairment of learning and memory in laboratory animals. The purpose of this study was to examine the effect of occlusal reconstruction after long-term loss of molars on spatial memory by using 8-arm radial maze and by assessing histopathological changes of neuron density in the hippocampus. Experimental dentures were inserted into the oral cavities of molarless rats to recover the occlusal support. Age-matched groups of control, molarless and denture-wearing rats were trained to perform the maze tasks. The difference of the error incidence in the maze task was evaluated between three groups. The difference of neuron density between three groups was also evaluated at the end of the maze task. Serum corticosterone levels were also measured to estimate the chronic stress, which could be caused by extraction, insertion of the experimental denture or any experimental procedure. The error incidence in the denture-wearing group was significantly higher than that of the control group, but significantly lower than that of the molarless group. Significant differences of neuron density were observed between three groups in each of the hippocampal CA1, CA3 and DG subfields. No significant difference of the serum corticosterone levels between three groups could be observed. From the results of this study, it was suggested that the recovery of occlusal support would bring amelioration of cognitive impairment concomitant with long period loss of molars in rats.


Assuntos
Hipocampo/patologia , Arcada Parcialmente Edêntula/reabilitação , Neurônios/patologia , Memória Espacial/fisiologia , Animais , Corticosterona/sangue , Masculino , Maxila , Aprendizagem em Labirinto , Dente Molar , Ratos , Ratos Wistar , Estresse Psicológico/sangue , Resultado do Tratamento
19.
Ann Surg Oncol ; 21 Suppl 4: S546-54, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24562936

RESUMO

BACKGROUND: In the tumor microenvironment, factors inhibiting the targeting of cancer cells by activated T cells have recently been noted. B7-H3 belongs to the B7 superfamily of immune regulatory ligands and plays an important role in the adaptive immune response of co-inhibitory/stimulatory factors in regulating T cells. However, the degree to which B7-H3 directly affects tumor immune evasion mechanisms remains unclear, particularly in patients with breast cancer. Regulatory T cells (Tregs) are known as a key player in the inhibition of immune mechanisms. The present study demonstrated that expression of B7-H3 on tumor cells and the number of Tregs in the tumor microenvironment independently affected prognosis in breast cancer patients. METHODS: We immunohistochemically investigated the presence of B7-H3 and forkhead box P3 (Foxp3)-positive Tregs in pathological specimens from 90 patients with breast cancer. RESULTS: Positive B7-H3 expression was associated with shorter recurrence-free survival (RFS) (p = 0.014). A higher percentage of Foxp3-positive cells also correlated with shorter RFS (p = 0.039). Multivariate analysis showed B7-H3 as an independent factor on RFS. Foxp3 expression in tumor-infiltrating lymphocytes (TILs) correlated significantly with larger tumor size (>2 cm), expression of human epidermal growth factor receptor 2 (HER2), and higher nuclear grade (p = 0.003, p < 0.001, p = 0.001, respectively). No correlation was identified between expression of B7-H3 and the percentage of Foxp3-positive TILs. CONCLUSIONS: B7-H3 and Foxp3 can be regarded as markers of poor prognosis in breast cancer. These expressions were not correlated, suggesting that B7-H3 expression plays an independent role in tumor immune evasion, regardless of Tregs.


Assuntos
Antígenos B7/análise , Neoplasias da Mama/química , Carcinoma Ductal de Mama/química , Linfócitos do Interstício Tumoral , Linfócitos T Reguladores , Evasão Tumoral , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/imunologia , Carcinoma Ductal de Mama/patologia , Intervalo Livre de Doença , Feminino , Fatores de Transcrição Forkhead/análise , Humanos , Contagem de Linfócitos , Linfócitos do Interstício Tumoral/química , Pessoa de Meia-Idade , Receptor ErbB-2/análise , Taxa de Sobrevida , Linfócitos T Reguladores/química , Carga Tumoral , Microambiente Tumoral/imunologia
20.
Br J Dermatol ; 170(4): 922-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24329764

RESUMO

BACKGROUND: Current treatment with biologics has produced dramatic therapeutic effects in patients with psoriasis, although these agents occasionally decrease in efficacy. One of the main factors responsible for this attenuation is attributed to the development of antidrug antibodies (ADAs). OBJECTIVES: To analyse the relationship between serum drug concentrations, the presence of ADAs and treatment efficacy of adalimumab and infliximab, and to determine the optimal use of these biologics. METHODS: This was a 1-year prospective study in the dermatology departments of Kobe University Hospital and collaborating hospitals. All patients starting a regimen of adalimumab and infliximab for psoriasis were included. We measured the serum concentration of the drugs and titres of antibodies to adalimumab and infliximab, as well as the Psoriasis Area and Severity Index scores at weeks 0, 4, 12, 24 and 48 during the first year of treatment. RESULTS: We observed a 50% positive rate of ADAs to adalimumab, and a 41% positive rate of ADAs to infliximab. The titres of ADAs showed a wide range from low to high titres. In the high-titre groups, the patients exhibited a decreased clinical response, and demonstrated a negative correlation between titre and clinical response. However, an equivalent therapeutic effect was observed between the low-titre group and the group with no antibodies detected for adalimumab. For infliximab, the patients with ADAs showed decreased clinical response. An apparent negative correlation between antibody production and reduced clinical response was observed. CONCLUSIONS: Two biologics, adalimumab and infliximab, showed different therapeutic behaviour. The measurement of ADAs and drug concentrations has important implications for treatment with biologics.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/fisiologia , Fármacos Dermatológicos/uso terapêutico , Psoríase/tratamento farmacológico , Adalimumab , Anticorpos Monoclonais/sangue , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais Humanizados/sangue , Anticorpos Monoclonais Humanizados/imunologia , Formação de Anticorpos/efeitos dos fármacos , Fatores Biológicos/uso terapêutico , Fármacos Dermatológicos/sangue , Fármacos Dermatológicos/imunologia , Feminino , Humanos , Infliximab , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Psoríase/imunologia , Resultado do Tratamento
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