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The Rare-RI Ring (R3) is a recently commissioned cyclotronlike storage ring mass spectrometer dedicated to mass measurements of exotic nuclei far from stability at Radioactive Isotope Beam Factory (RIBF) in RIKEN. The first application of mass measurement using the R3 mass spectrometer at RIBF is reported. Rare isotopes produced at RIBF-^{127}Sn, ^{126}In, ^{125}Cd, ^{124}Ag, ^{123}Pd-were injected in R3. Masses of ^{126}In, ^{125}Cd, and ^{123}Pd were measured whereby the mass uncertainty of ^{123}Pd was improved. This is the first reported measurement with a new storage ring mass spectrometry technique realized at a heavy-ion cyclotron and employing individual injection of the preidentified rare nuclei. The latter is essential for the future mass measurements of the rarest isotopes produced at RIBF. The impact of the new ^{123}Pd result on the solar r-process abundances in a neutron star merger event is investigated by performing reaction network calculations of 20 trajectories with varying electron fraction Y_{e}. It is found that the neutron capture cross section on ^{123}Pd increases by a factor of 2.2 and ß-delayed neutron emission probability, P_{1 n}, of ^{123}Rh increases by 14%. The neutron capture cross section on ^{122}Pd decreases by a factor of 2.6 leading to pileup of material at A=122, thus reproducing the trend of the solar r-process abundances. The trend of the two-neutron separation energies (S_{2n}) was investigated for the Pd isotopic chain. The new mass measurement with improved uncertainty excludes large changes of the S_{2n} value at N=77. Such large increase of the S_{2n} values before N=82 was proposed as an alternative to the quenching of the N=82 shell gap to reproduce r-process abundances in the mass region of A=112-124.
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Interaction cross sections for ^{42-51}Ca on a carbon target at 280 MeV/nucleon have been measured for the first time. The neutron number dependence of derived root-mean-square matter radii shows a significant increase beyond the neutron magic number N=28. Furthermore, this enhancement of matter radii is much larger than that of the previously measured charge radii, indicating a novel growth in neutron skin thickness. A simple examination based on the Fermi-type distribution, and mean field calculations point out that this anomalous enhancement of the nuclear size beyond N=28 results from an enlargement of the core by a sudden increase in the surface diffuseness of the neutron density distribution, which implies the swelling of the bare ^{48}Ca core in Ca isotopes beyond N=28.
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Telomerase participates in malignant transformation or immortalization of cells, and has attracted attention as an anticancer drug screening and diagnostic tumor marker. We developed a novel telomerase assay called the PPDK-luciferin-luciferase system bioluminescence assay (PLLBA) using pyruvate phosphate dikinase (PPDK). In this assay, pyrophosphate produced by the telomerase reaction and polymerase chain reaction (PCR) is converted to ATP by PPDK, and ATP is detected by the firefly luciferin-luciferase reaction. In this work, telomerase substrate was obtained in accordance with the telomeric repeat amplification protocol (TRAP). Telomerase-positive (500 cells/assay), -inactive (heated for 10 min at 85 °C) and -negative (only Chaps lysis buffer) samples were used. As a result, the findings clearly showed that the signal-to-noise (S/N) ratio of the positive cells was 39.5. After the telomerase reaction and PCR, PLLBA was completed ~ 120 s later. A high level of reproducibility was obtained with - coefficient of variation (CV) of 4.1% (positive cells). The detection limit for cells using telomerase was one cell per assay. This assay for telomerase activity was also shown to be adaptable to human cancer-derived cell lines.
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Luciferina de Vaga-Lumes/análise , Luciferases/análise , Telomerase/análise , Sequência de Bases , Primers do DNA , Humanos , Limite de Detecção , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
BACKGROUND: Adolescents and young adults (AYAs) represent a small proportion of patients with cancer. The genomic profiles of AYA patients with cancer are not well-studied, and outcomes of genome-matched therapies remain largely unknown. PATIENTS AND METHODS: We investigated differences between Japanese AYA and older adult (OA) patients in genomic alterations, therapeutic evidence levels, and genome-matched therapy usage by cancer type. We also assessed treatment outcomes. RESULTS: AYA patients accounted for 8.3% of 876 cases. Microsatellite instability-high and/or tumor mutation burden was less common in AYA patients (1.4% versus 7.7% in OA; P = 0.05). However, BRCA1 alterations were more common in AYA patients with breast cancer (27.3% versus 1.7% in OA; P = 0.01), as were MYC alterations in AYA patients with colorectal cancer (23.5% versus 5.8% in OA; P = 0.02) and sarcoma (31.3% versus 3.4% in OA; P = 0.01). Genome-matched therapy use was similar between groups, with overall survival tending to improve in both. However, in AYA patients, the small number of patients prevented statistical significance. Comprehensive genomic profiling-guided genome-matched therapy yielded encouraging results, with progression-free survival of 9.0 months in AYA versus 3.7 months in OA patients (P = 0.59). CONCLUSION: Our study suggests that tailored therapeutic approaches can benefit cancer patients regardless of age.
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Genômica , Neoplasias , Humanos , Feminino , Adolescente , Adulto Jovem , Masculino , Neoplasias/genética , Neoplasias/terapia , Adulto , Genômica/métodos , Medicina de Precisão/métodos , Pessoa de Meia-Idade , JapãoRESUMO
OBJECTIVES: To investigate the 'I-shaped' sign as a novel echocardiographic marker for antenatal diagnosis of d-transposition of the great arteries (dTGA) in routine cardiac examination, and to compare its prevalence in fetuses with dTGA, those with other congenital heart diseases (CHDs) and those with normal structural hearts. METHODS: This retrospective evaluation involved 1134 fetuses undergoing echocardiography to screen for CHD over a 4-year period. I-shaped sign was defined as the characteristic appearance of the aortic arch, resembling the letter 'I', from the most anterior to the most posterior point of the descending aorta visible in the three vessels and trachea view. The frequency of this sign was evaluated in cases with dTGA, those with other cardiac defects and those with normal cardiac structures. RESULTS: CHD was diagnosed in 671 (59.1%) cases, of which 31 (4.6%) had dTGA. I-shaped sign was observed in 30/31 (96.8%) cases of dTGA, compared with 31/640 (4.8%) cases with other cardiac anomalies, which included single ventricle with pulmonary atresia or severe pulmonary stenosis, hypoplastic left heart syndrome with aortic atresia, corrected transposition of the great arteries, and double outlet right ventricle with malposition of the great arteries. I-shaped sign was detected significantly more frequently in the dTGA group compared with the normal group and with the other CHDs group (both P < 0.001) and had 96.8% sensitivity and 97.1% specificity for diagnosis of dTGA. Importantly, I-shaped sign was never observed in fetuses with structurally normal hearts. CONCLUSIONS: Detection on echocardiography of an extremely long vessel with a marked I-shape should raise suspicion of cardiac anomaly, especially dTGA. This marker may therefore aid in the prenatal diagnosis of dTGA during routine ultrasound examination.
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Mediastino/diagnóstico por imagem , Transposição dos Grandes Vasos/diagnóstico por imagem , Ultrassonografia Pré-Natal/métodos , Adolescente , Adulto , Ecocardiografia/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Gravidez de Gêmeos , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto JovemRESUMO
This retrospective study identified the risk factors for fracture of veneering materials and screw loosening of implant-supported fixed partial dentures in partially edentulous cases. The study group included a total of 182 patients who were installed 219 suprastructures at the Fixed Prosthodontic Clinic of Okayama University Dental Hospital between February 1990 and March 2005 and were subdivided in two subgroups: 120 patients (149 facing suprastructures) were included in the subgroup to investigate the risk factors of fracture of veneering materials, and 81 patients (92 suprastructures) were included in the subgroup to identify the risk factors of abutment screw loosening. Each patient was followed up from the day of suprastructure installation until March, 2005. A Cox proportional hazards regression model was used to identify the risk factors related to technical complications, and eight factors were regarded as candidate risk factors. Screw retention was the significant risk factor for fracture of veneering materials, whereas connection of suprastructures with natural tooth was the significant risk factor for screw loosening. It was suggested that screw retention was a significant risk factor for the fracture of veneering materials, and connection of suprastructures with natural tooth was a significant risk factor for screw loosening. Future studies, involving dynamic factors (e.g. bruxism) as predictors as well, are more helpful to discuss the risk factor of fracture of veneering materials and screw loosening.
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Parafusos Ósseos/efeitos adversos , Prótese Dentária Fixada por Implante/efeitos adversos , Falha de Restauração Dentária/estatística & dados numéricos , Facetas Dentárias/efeitos adversos , Arcada Parcialmente Edêntula/reabilitação , Dente Suporte , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
Asthma is the most common chronic lower respiratory disease in childhood throughout the world. Several guidelines and/or consensus documents are available to support medical decisions on pediatric asthma. Although there is no doubt that the use of common systematic approaches for management can considerably improve outcomes, dissemination and implementation of these are still major challenges. Consequently, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), recently formed by the EAACI, AAAAI, ACAAI, and WAO, has decided to propose an International Consensus on (ICON) Pediatric Asthma. The purpose of this document is to highlight the key messages that are common to many of the existing guidelines, while critically reviewing and commenting on any differences, thus providing a concise reference. The principles of pediatric asthma management are generally accepted. Overall, the treatment goal is disease control. To achieve this, patients and their parents should be educated to optimally manage the disease, in collaboration with healthcare professionals. Identification and avoidance of triggers is also of significant importance. Assessment and monitoring should be performed regularly to re-evaluate and fine-tune treatment. Pharmacotherapy is the cornerstone of treatment. The optimal use of medication can, in most cases, help patients control symptoms and reduce the risk for future morbidity. The management of exacerbations is a major consideration, independent of chronic treatment. There is a trend toward considering phenotype-specific treatment choices; however, this goal has not yet been achieved.
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Asma/diagnóstico , Asma/terapia , Adolescente , Asma/classificação , Asma/prevenção & controle , Criança , Pré-Escolar , Humanos , Lactente , Recém-NascidoRESUMO
The purposes of this study were to determine whether a response shift was observable after partial denture treatment and to identify the predictors that influenced the response shift magnitude and direction. A total of 173 consecutive patients with no more than eight missing teeth who received implant-supported, fixed or removable partial dentures at Okayama University Dental Hospital were asked to complete a full-version Oral Health-Related Quality of Life (OHRQoL) questionnaire before (pre-test) and after treatment (post-test). Additionally, a short form (then-test) consisting of seven questions selected from the full version had its reliability verified and was utilised to retrospectively assess the pre-treatment OHRQoL status. The difference between the summary scores of the then-test and the pre-test determined the response shift magnitude and direction. The then-test mean score (22·9 ± 6·6) was significantly lower (worse OHRQoL) than that of the pre-test (26·4 ± 5·2). The response shift effect size was of moderate magnitude and negative direction (d = -0·78). A multiple regression analysis showed that age (younger patients) (P < 0·01), number of replaced teeth (fewer) (P < 0·01) and pre-test scores (lower) (P < 0·01) were the significant predictors for response shift. In conclusion, a response shift phenomenon with negative and moderate effect size was observed after partial denture treatment. The significant predictor variables were young age, fewer numbers of replaced teeth and lower pre-test scores.
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Prótese Parcial/psicologia , Arcada Parcialmente Edêntula/reabilitação , Saúde Bucal , Satisfação do Paciente , Qualidade de Vida , Perda de Dente/reabilitação , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Inquéritos e Questionários , Resultado do Tratamento , Adulto JovemRESUMO
This Letter presents the discovery of macroscale electron temperature fluctuations with a long radial correlation length comparable to the plasma minor radius in a toroidal plasma. Their spatiotemporal structure is characterized by a low frequency of â¼1-3 kHz, ballistic radial propagation, a poloidal or toroidal mode number of m/n=1/1 (or 2/1), and an amplitude of â¼2% at maximum. Nonlinear coupling between the long-range fluctuations and the microscopic fluctuations is identified. A change of the amplitude of the long-range fluctuation is transmitted across the plasma radius at the velocity which is of the order of the drift velocity.
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The velocity distribution function is a statistical description that connects particle kinetics and macroscopic parameters in many-body systems. Laser-induced fluorescence (LIF) spectroscopy is utilized to measure the local velocity distribution function in spatially inhomogeneous plasmas. However, the analytic form of such a function for the system of interest is not always clear under the intricate factors in non-equilibrium states. Here, we propose a novel approach to select the valid form of the velocity distribution function based on Bayesian statistics. We formulate the Bayesian inference of ion velocity distribution function and apply it to LIF spectra locally observed at several positions in a linear magnetized plasma. We demonstrate evaluating the spatial inhomogeneity by verifying each analytic form of the local velocity distribution function. Our approach is widely applicable to experimentally establish the velocity distribution function in plasmas and fluids, including gases and liquids.
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We have characterized extrachromosomal circular DNAs from adult mouse spleen cells that were induced to switch to immunoglobulin A (IgA) with bacterial lipopolysaccharide (LPS) and transforming growth factor beta (TGF-beta), and identified breakpoints of S mu/S gamma 3, S mu/S gamma 2, S mu/S alpha, S gamma 3/S alpha, and S gamma 2/S alpha recombinants. The S mu recombination donor sites clustered in the 3' half of the S mu region, while the S alpha recombination acceptor sites clustered in the 5' half of the S alpha region. In addition, donor and acceptor sites of S gamma regions also clustered in the 3' and 5' parts, respectively. These site preferences are in sharp contrast to the dispersed distribution of S mu/S gamma 1 breakpoints within both S mu and S gamma 1 regions upon IgG1 switch induced by LPS and interleukin 4. Our results support the hypotheses that TGF-beta increases the frequency of switch recombination events to IgA and that the switch recombination to IgA often proceeds by successive recombination of S mu/S gamma and S gamma/S alpha.
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Genes de Troca , Imunoglobulina G/genética , Região de Troca de Imunoglobulinas , Recombinação Genética , Fator de Crescimento Transformador beta/farmacologia , Animais , Sequência de Bases , Clonagem Molecular , DNA Circular/genética , Feminino , Biblioteca Gênica , Genes de Troca/efeitos dos fármacos , Região de Troca de Imunoglobulinas/efeitos dos fármacos , Interleucina-4/farmacologia , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos BALB C , Modelos Genéticos , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos , Plasmídeos , Recombinação Genética/efeitos dos fármacos , Mapeamento por Restrição , Baço/imunologiaRESUMO
A streamer, which is a bunching of drift-wave fluctuations, and its mediator, which generates the streamer by coupling with other fluctuations, have been observed in a cylindrical magnetized plasma. Their radial structures were investigated in detail by using the biphase analysis. Their quasi-two-dimensional structures were revealed to be equivalent with a pair of fast and slow modes predicted by a nonlinear Schrödinger equation based on the Hasegawa-Mima model.
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BACKGROUND: Atopic dermatitis is a disease of skin barrier dysfunction and outside stimuli can cross the skin barrier. OBJECTIVES: To examine a new method for evaluating the outside to inside skin transparency with a colorimeter and yellow dyes. METHODS: In study 1, a total of 28 volunteer subjects (24 normal and four with atopic dermatitis) participated. After provocation with yellow dye, the skin colour of all the subjects was measured using a colorimeter. The skin transparency index was calculated by the changes of the skin colour to yellow. Other variables of skin function, including transepidermal water loss (TEWL) and stratum corneum hydration, were also measured. In study 2, the skin transparency index was evaluated for a cohort of 38 patients with atopic dermatitis, 27 subjects with dry skin and 29 healthy controls. RESULTS: In study 1, the measurement of skin colour (b*) using tartrazine showed good results. There was a significant relationship between the skin transparency index with tartrazine and the atopic dermatitis score (P = 0.014). No other measurements of skin function, including the TEWL, were correlated. In study 2, the skin transparency index score obtained with tartrazine in the patients with atopic dermatitis was significantly higher than that of the controls and those with dry skin (P < 0.001 and P = 0.022, respectively). However, the TEWL in patients with atopic dermatitis was not significantly higher than that of patients with dry skin and the TEWL in subjects with dry skin was not higher than that of the controls. CONCLUSIONS: This method, which used a colorimeter and food dye, is noninvasive, safe and reliable for the evaluation of out-in skin transparency and can demonstrate the characteristic dysfunction in the skin barrier in patients with atopic dermatitis.
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Dermatite Atópica/fisiopatologia , Corantes de Alimentos/uso terapêutico , Pele/fisiopatologia , Tartrazina/uso terapêutico , Adolescente , Análise de Variância , Criança , Colorimetria , Dermatite Atópica/patologia , Feminino , Humanos , Masculino , Estudos Prospectivos , Índice de Gravidade de Doença , Pele/patologia , Absorção Cutânea , Pigmentação da Pele/fisiologia , Perda Insensível de Água/fisiologia , Adulto JovemRESUMO
The cytokines LIF (leukemia inhibitory factor) and BMP2 (bone morphogenetic protein-2) signal through different receptors and transcription factors, namely STATs (signal transducers and activators of transcription) and Smads. LIF and BMP2 were found to act in synergy on primary fetal neural progenitor cells to induce astrocytes. The transcriptional coactivator p300 interacts physically with STAT3 at its amino terminus in a cytokine stimulation-independent manner, and with Smad1 at its carboxyl terminus in a cytokine stimulation-dependent manner. The formation of a complex between STAT3 and Smad1, bridged by p300, is involved in the cooperative signaling of LIF and BMP2 and the subsequent induction of astrocytes from neural progenitors.
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Citocinas/farmacologia , Proteínas de Ligação a DNA/metabolismo , Interleucina-6 , Proteínas Nucleares/metabolismo , Receptores de Fatores de Crescimento , Transdução de Sinais , Transativadores/metabolismo , Ativação Transcricional , Fator de Crescimento Transformador beta , Animais , Astrócitos/citologia , Proteína Morfogenética Óssea 2 , Receptores de Proteínas Morfogenéticas Ósseas , Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas Morfogenéticas Ósseas/farmacologia , Células COS , Diferenciação Celular , Núcleo Celular/metabolismo , Células Cultivadas , Proteína p300 Associada a E1A , Proteína Glial Fibrilar Ácida/genética , Inibidores do Crescimento/metabolismo , Inibidores do Crescimento/farmacologia , Fator Inibidor de Leucemia , Subunidade alfa de Receptor de Fator Inibidor de Leucemia , Linfocinas/metabolismo , Linfocinas/farmacologia , Camundongos , Regiões Promotoras Genéticas , Receptores de Superfície Celular/metabolismo , Receptores de Citocinas/metabolismo , Receptores de OSM-LIF , Fator de Transcrição STAT3 , Deleção de Sequência , Proteínas Smad , Proteína Smad1 , Células-Tronco/citologia , Células-Tronco/metabolismo , Telencéfalo/embriologia , Telencéfalo/metabolismoRESUMO
BACKGROUND AND AIM: Magnifying endoscopy combined with narrow-band imaging (ME-NBI) has been used for differential diagnosis of various focal lesions. The aim of our study was to evaluate ME-NBI criteria for cancer diagnosis in superficial depressed gastric lesions in comparison to conventional white light endoscopy (WLE). PATIENTS AND METHODS: ME-NBI and WLE images of 100 superficial gastric depressions (55 depressed cancers, 45 benign depressions) were independently evaluated by 11 endoscopists blinded to the diagnosis in each case. The presence or absence of predefined ME-NBI findings relating to microvasculature and fine mucosal structure (FMS) was recorded. A general diagnosis of benign or malignant also had to be given on the basis of a general assessment of features of color and shape as shown in the ME-NBI and WLE images, respectively, without regard to any prespecified criteria. RESULTS: Multivariate and ROC analysis demonstrated that the triad of FMS disappearance, microvascular dilation, and heterogeneity appeared to be the best combination for diagnosis of gastric cancer. ME-NBI diagnosis with the triad attained a good specificity (85 %, theoretically calculated if all of the triad were positive), which was significantly ( P < 0.001) superior to WLE general diagnosis (65 %), and comparable with ME-NBI general diagnosis (80 %). The sensitivities of the three diagnoses (ME-NBI with the triad 69 %, WLE general diagnosis 71 %, ME-NBI general diagnosis 72 %) were comparably moderate. The kappa values (interobserver concordance) for ME-NBI diagnosis with the triad (0.47) and ME-NBI general diagnosis (0.48) were superior to the kappa value for WLE diagnosis (0.34). CONCLUSION: The triad of FMS disappearance, microvascular dilation, and heterogeneity has good specificity for the diagnosis of superficial depressed gastric carcinoma, but the sensitivity needs to be improved.
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Esofagoscopia/métodos , Mucosa Gástrica/irrigação sanguínea , Mucosa Gástrica/patologia , Gastropatias/diagnóstico , Gastropatias/patologia , Idoso , Diagnóstico Diferencial , Humanos , Microvasos/patologia , Pessoa de Meia-Idade , Análise Multivariada , Variações Dependentes do Observador , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/patologia , Curva ROC , Estômago/irrigação sanguínea , Estômago/patologia , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologiaRESUMO
The purpose of this study was to investigate a practical patient dose index for assessing the patient organ dose from a cone-beam computed tomography (CBCT) scan by comparing eight dose indices, i.e. CTDI100, CTDIIEC, CTDI∞, midpoint doses f(0)PMMA for a cylindrical polymethyl methacrylate (PMMA) phantom, f(0)Ap for an anthropomorphic phantom and f(0)Pat for a prostate cancer patient, as well as the conventional size specific dose estimations (SSDEconv) and modified SSDE (SSDEmod), with organ dose for the prostate (ODprost) obtained via Monte Carlo (MC) simulation. The ODprost was the reference dose used to find the practical dose index at the center of the pelvic region of a prostate cancer patient. The smallest error rate with respect to the ODprost of 19.3 mGy (reference) among eight dose indices was 5% for f(0)Pat. The practical patient dose index was the f(0)Pat, which showed the smallest error with respect to the reference dose.
Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Doses de Radiação , Humanos , Masculino , Método de Monte Carlo , Órgãos em Risco , Imagens de FantasmasRESUMO
BACKGROUND AND PURPOSE: Both adhesive and nonabrasive embolic agents are available for arteriovenous malformation (AVM) embolization. The purpose of this study was to evaluate a novel ethanol-based nonadhesive liquid embolic material in a swine AVM model. MATERIALS AND METHODS: Eudragit (copolymer of methyl and butyl methacrylate and dimethylaminoethyl methacrylate) was dissolved in 50% ethanol and 50% iopamidol. Eudragit was injected into 9 retia mirabilia (RMs). Ethanol and iopamidol mixture were injected into 4 RMs for comparison. Three RMs embolized with Eudragit mixture were evaluated both angiographically and histopathologically acutely (3-24 hours) and at 30 days and 90 days after embolization. RESULTS: No procedural complications from Eudragrit embolization were noted, including retention or adhesion of the microcatheter. Various degrees of inflammation were observed in the acute and 30-day specimens. Two RMs showed partial recanalization on both histopathology and follow-up angiography in the 30-day group. Arterial fibrosis and calcification were observed in the 30- and 90-day specimens. The internal elastic lamina was disrupted in the 30- and 90-day specimens, but there was no evidence of Eudragit extravasation or hemorrhage. Endothelial damage was seen in all specimens and was particularly severe in the 30- and 90-day specimens. CONCLUSION: Eudragit polymer induced inflammation in thrombosis similar to n-butyl 2-cyanoacrylate, but without the disadvantages of perivascular hemorrhage and extravasation of embolization material. Although recanalization of some embolized RMs was noted, further investigation into Eudragit as a potentially useful embolic material for brain AVMs is warranted.
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Acrilatos/administração & dosagem , Cavidades Cranianas/efeitos dos fármacos , Cavidades Cranianas/diagnóstico por imagem , Embolização Terapêutica/métodos , Polímeros/administração & dosagem , Animais , Radiografia , Suínos , Resultado do TratamentoRESUMO
Magnification of a polarization angle with Littrow layout gratings has been developed. High magnification with a factor of 7.7 using two gratings in Littrow layout was experimentally proved. The magnification range was investigated by calculation at a wavelength of 10.6 µm. The method can be applied for a high magnification factor >30. Larger groove numbers and smaller blaze angles are suitable for the large magnification. Statistical fluctuation of the diffracted polarization angle is compared with that of the incident polarization angle.
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The p53 tumor-suppressor gene regulates apoptosis through the transcriptional activation of its target genes. The expression of the axon-guidance molecule UNC5B (also designated p53RDL1), which is a receptor for netrin-1, is directly regulated by p53. In the absence of netrin-1, UNC5B mediates p53-dependent apoptosis. Conversely, in the presence of netrin-1, p53-induced apoptosis is inhibited through the signaling pathway activated by the interaction between netrin-1 and UNC5B. A number of other molecules that are involved in axon guidance are inactivated in human cancers and are also regulated by p53. These findings suggest a close link between axon-guidance molecules and tumorigenesis.
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Apoptose/fisiologia , Axônios/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Proteína Supressora de Tumor p53/fisiologia , Animais , HumanosRESUMO
The question addressed in this study is how does the protein-DNA complexation affect the structure and dynamics of DNA and protein in aqueous solution. We examined the interaction of calf-thymus DNA with human serum albumin (HSA) in aqueous solution at physiological conditions, using constant DNA concentration of 12.5 mM (phosphate) and various HSA contents 0.25 to 2% or 0.04 to 0.3 mM. Affinity capillary electrophoresis and FTIR spectroscopic methods were used to determine the protein binding mode, the association constant, sequence preference, and the biopolymer secondary structural changes in the HSA-DNA complexes. Spectroscopic evidence showed two types of HSA-DNA complexes with strong binding of K(1) = 4.5 x 10(5) M(-1) and weak binding of K(2) = 6.10 x 10(4) M(-1). The two major binding sites were located on the G-C bases and the backbone PO(2) group. The protein-DNA interaction stabilizes the HSA secondary structure. A minor alteration of B-DNA structure was observed, while no major protein conformational changes occurred.