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1.
Phys Rev Lett ; 126(18): 186401, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34018791

RESUMO

The energy spectrum of positronium atoms generated at a solid surface reflects the electron density of states (DOS) associated solely with the first surface layer. Using spin-polarized positrons, the spin-dependent surface DOS can be studied. For this purpose, we have developed a spin-polarized positronium time-of-flight spectroscopy apparatus based on a ^{22}Na positron source and an electrostatic beam transportation system, which enables the sampling of topmost surface electrons around the Γ point and near the Fermi level. We applied this technique to nonmagnetic Pt(111) and W(001), ferromagnetic Ni(111), Co(0001) and graphene on them, Co_{2}FeGa_{0.5}Ge_{0.5} (CFGG) and Co_{2}MnSi (CMS). The results showed that the electrons of Ni(111) and Co(0001) surfaces have characteristic negative spin polarizations, while these spin polarizations vanished upon graphene deposition, suggesting that the spin polarizations of graphene on Ni(111) and Co(0001) were mainly induced at the Dirac points that were out of range in the present measurement. The CFGG and CMS surfaces also exhibited only weak spin polarizations suggesting that the half-metallicity expected for these bulk states was not maintained at the surfaces.

2.
Phys Rev Lett ; 125(23): 236806, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33337194

RESUMO

The surface magnetism of Fe(001) was studied in an atomic layer-by-layer fashion by using the in situ iron-57 probe layer method with a synchrotron Mössbauer source. The observed internal hyperfine field H_{int} exhibits a marked decrease at the surface and an oscillatory behavior with increasing depth in the individual upper four layers below the surface. The calculated layer-depth dependencies of the effective hyperfine field |H_{eff}|, isomer shift δ, and quadrupole shift 2ϵ agree well with the observed experimental parameters. These results provide the first experimental evidence for the magnetic Friedel oscillations, which penetrate several layers from the Fe(001) surface.

3.
Phys Rev Lett ; 124(8): 081101, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32167338

RESUMO

Searching for space-time variations of the constants of Nature is a promising way to search for new physics beyond general relativity and the standard model motivated by unification theories and models of dark matter and dark energy. We propose a new way to search for a variation of the fine-structure constant using measurements of late-type evolved giant stars from the S star cluster orbiting the supermassive black hole in our Galactic Center. A measurement of the difference between distinct absorption lines (with different sensitivity to the fine structure constant) from a star leads to a direct estimate of a variation of the fine structure constant between the star's location and Earth. Using spectroscopic measurements of five stars, we obtain a constraint on the relative variation of the fine structure constant below 10^{-5}. This is the first time a varying constant of nature is searched for around a black hole and in a high gravitational potential. This analysis shows new ways the monitoring of stars in the Galactic Center can be used to probe fundamental physics.

4.
Phys Rev Lett ; 123(21): 216601, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31809165

RESUMO

The impact of electron correlation on the Dirac semimetal state is investigated for perovskite CaIrO_{3} in terms of the magnetotransport properties under varying pressures. The reduction of electron correlation with a pressure of 1 GPa enhances the Fermi velocity as much as 40%, but it reduces the mobility by an order of magnitude by detuning the Dirac node from the Fermi energy. Moreover, the giant magnetoresistance at the quantum limit due to the one-dimensional confinement of Dirac electrons is critically suppressed under pressure. These results indicate that the electron correlation is a crucial knob for controlling the transport of a correlated Dirac semimetal.

5.
J Dairy Sci ; 102(11): 9559-9569, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31495632

RESUMO

Antiviral neuraminidase inhibitors, such as oseltamivir, zanamivir, and peramivir, are widely used for treatment of influenza virus infection. We reported previously that oseltamivir inhibits the viral growth cycle, ameliorates symptoms, and reduces viral antigen quantities. Suppressed viral antigen production, however, induces a reduction of acquired antiviral humoral immunity, and increases the incidence of re-infection rate in the following year. To achieve effective treatment of influenza virus infection, it is necessary to overcome these adverse effects of antiviral neuraminidase inhibitors. Feeding of yogurt fermented with Lactobacillus delbrueckii ssp. bulgaricus (L. bulgaricus) OLL1073R-1 is reported to have immune-stimulatory effects on influenza virus infection in mice and humans. In the present study, we assessed the effect of feeding L. bulgaricus OLL1073R-1 yogurt cultures (YC) on local and systemic humoral immune responses, which were suppressed by oseltamivir treatment, in mice infected with influenza A virus. Yogurt culture (1.14 × 108 cfu/0.4 mL per mouse per day) or sterile water (vehicle) was administered by intragastric gavage for 35 d. At d 22, influenza A virus/Puerto Rico/8/34 (H1N1) (PR8; 0.5 pfu/15 µL per mouse) was instilled intranasally, followed immediately by oral administration of oseltamivir (50 µg/100 µL per mouse, twice daily) or 5% methylcellulose (100 µL/mouse) as a vehicle for 13 d. Titers of anti-PR8-specific IgG and IgA in serum and mucosal secretory IgA (S-IgA) and IgG in bronchoalveolar lavage fluid (BALF) were analyzed by ELISA at 14 d after infection. Oseltamivir significantly suppressed the induction of anti-PR8-specific IgG and IgA in serum and S-IgA and IgG in BALF after infection. Feeding YC mildly but significantly stimulated production of PR8-specific IgA in serum, S-IgA in BALF, and IgG in serum without changing the IgG2a:IgG1 ratio. We analyzed the neutralizing activities against PR8 in serum and BALF and found that oseltamivir also reduced protective immunity, and YC feeding abrogated this effect. The immune-stimulatory tendency of YC on anti-PR8-specific IgA and IgG titers in serum and BALF was also detected in mice re-infected with PR8, but the effect was insignificant, unlike the effect of YC in the initial infection.


Assuntos
Antivirais/uso terapêutico , Imunidade Humoral/efeitos dos fármacos , Lactobacillus delbrueckii , Neuraminidase/antagonistas & inibidores , Infecções por Orthomyxoviridae/imunologia , Oseltamivir/uso terapêutico , Probióticos/uso terapêutico , Proteínas Virais/antagonistas & inibidores , Ração Animal , Animais , Antivirais/efeitos adversos , Antivirais/antagonistas & inibidores , Inibidores Enzimáticos/uso terapêutico , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Lactobacillus delbrueckii/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/dietoterapia , Infecções por Orthomyxoviridae/tratamento farmacológico , Oseltamivir/efeitos adversos , Oseltamivir/antagonistas & inibidores , Iogurte
6.
Skin Res Technol ; 24(4): 562-569, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29536579

RESUMO

BACKGROUND: Hyaluronan (HA) is an important constituent of extracellular matrix (ECM) in the skin, and HA degradation mediated by HYBID (KIAA1199) is suggested to be implicated in facial skin wrinkling in Japanese women. Ethnic difference in skin wrinkle formation is known between Caucasian and Japanese women, but no information is available for the relations of HA and HYBID expression levels with skin wrinkling in Caucasian women. METHODS: The skin surface roughness at the eye corner of the Caucasian female subjects was measured, and the skin specimens biopsied from the same areas were subjected to microarray gene analysis, HA staining, and immunohistochemistry for HYBID. RESULTS: Among the ECM genes and those related to ECM metabolism, only HYBID expression levels positively correlated with the skin roughness parameters. When the skin sample groups with high expression of HYBID or low expression of HYBID were compared, the HA staining intensity and the ratio of HYBID-immunoreactive cells to total cells in the superficial dermis were significantly reduced and increased in the high-HYBID-expression group compared with the low-HYBID-expression group, respectively. CONCLUSION: Our data suggest that like Japanese women, HYBID-mediated reduction of HA in the superficial dermis is involved in the formation of wrinkles in Caucasian women.


Assuntos
Ácido Hialurônico/metabolismo , Proteínas/metabolismo , Envelhecimento da Pele/etnologia , Pele/metabolismo , População Branca , Idoso , Biópsia , Feminino , Expressão Gênica , Humanos , Ácido Hialurônico/genética , Hialuronoglucosaminidase , Pessoa de Meia-Idade , Proteínas/genética , Pele/patologia , Envelhecimento da Pele/patologia , Envelhecimento da Pele/fisiologia
7.
Phys Rev Lett ; 118(21): 211101, 2017 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-28598651

RESUMO

We demonstrate that short-period stars orbiting around the supermassive black hole in our Galactic center can successfully be used to probe the gravitational theory in a strong regime. We use 19 years of observations of the two best measured short-period stars orbiting our Galactic center to constrain a hypothetical fifth force that arises in various scenarios motivated by the development of a unification theory or in some models of dark matter and dark energy. No deviation from general relativity is reported and the fifth force strength is restricted to an upper 95% confidence limit of |α|<0.016 at a length scale of λ=150 astronomical units. We also derive a 95% confidence upper limit on a linear drift of the argument of periastron of the short-period star S0-2 of |ω[over ˙]_{S0-2}|<1.6×10^{-3} rad/yr, which can be used to constrain various gravitational and astrophysical theories. This analysis provides the first fully self-consistent test of the gravitational theory using orbital dynamic in a strong gravitational regime, that of a supermassive black hole. A sensitivity analysis for future measurements is also presented.

8.
Phys Rev Lett ; 116(19): 197001, 2016 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-27232035

RESUMO

We study the temperature-dependent electronic B_{1g} Raman response of a slightly underdoped single crystal HgBa_{2}Ca_{2}Cu_{3}O_{8+δ} with a superconducting critical temperature T_{c}=122 K. Our main finding is that the superconducting pair-breaking peak is associated with a dip on its higher-energy side, disappearing together at T_{c}. This result reveals a key aspect of the unconventional pairing mechanism: spectral weight lost in the dip is transferred to the pair-breaking peak at lower energies. This conclusion is supported by cellular dynamical mean-field theory on the Hubbard model, which is able to reproduce all the main features of the B_{1g} Raman response and explain the peak-dip behavior in terms of a nontrivial relationship between the superconducting gap and the pseudogap.

9.
Phys Rev Lett ; 117(24): 247001, 2016 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-28009182

RESUMO

We use a surface-selective angle-resolved photoemission spectroscopy and unveil the electronic nature on the topmost layer of Sr_{2}RuO_{4} crystal, consisting of slightly rotated RuO_{6} octahedrons. The γ band derived from the 4d_{xy} orbital is found to be about three times narrower than that for the bulk. This strongly contrasts with a subtle variation seen in the α and ß bands derived from the one-dimensional 4d_{xz/yz}. This anomaly is reproduced by the dynamical mean-field theory calculations, introducing not only the on-site Hubbard interaction but also the significant Hund's coupling. We detect a coherence-to-incoherence crossover theoretically predicted for Hund's metals, which has been recognized only recently. The crossover temperature in the surface is about half that of the bulk, indicating that the naturally generated monolayer of reconstructed Sr_{2}RuO_{4} is extremely correlated and well isolated from the underlying crystal.

10.
Diabetes Obes Metab ; 18(7): 702-6, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26639943

RESUMO

This randomized, double-blind, placebo-controlled, crossover study was the first to determine the effects of luseogliflozin in combination with a low-carbohydrate diet (LCD) on 24-h glucose variability, assessed by continuous glucose monitoring (CGM). A total of 18 Japanese patients with type 2 diabetes were randomized into two groups, in which patients first received luseogliflozin 2.5 mg once daily then placebo for 8 days each, or vice versa. Patients took luseogliflozin or placebo with a normal-carbohydrate diet (NCD) on day 7 and with the LCD on day 8. CGM was performed on both days. Luseogliflozin significantly reduced glucose exposure in terms of the area under the curve over the course of 24 h when administered with the NCD (difference vs placebo: -555.6 mg/dl·h [1 mg/dl = 0.0556 mmol/l]; p < 0.001) or with the LCD (-660.7 mg/dl·h; p < 0.001). No hypoglycaemia was observed over 24 h with either diet. Although glucose levels were lower with the LCD than with the NCD in the placebo treatment period, luseogliflozin with the LCD improved glycaemic control throughout the day to nearly the same extent as luseogliflozin with the NCD, without inducing hypoglycaemia.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Dieta com Restrição de Carboidratos , Hipoglicemiantes/administração & dosagem , Sorbitol/análogos & derivados , Administração Oral , Glicemia/metabolismo , Estudos Cross-Over , Diabetes Mellitus Tipo 2/sangue , Método Duplo-Cego , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/farmacologia , Masculino , Pessoa de Meia-Idade , Transportador 2 de Glucose-Sódio , Inibidores do Transportador 2 de Sódio-Glicose , Sorbitol/administração & dosagem , Sorbitol/efeitos adversos , Sorbitol/farmacologia , Resultado do Tratamento
11.
Transpl Infect Dis ; 18(1): 93-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26613364

RESUMO

Adoptive immunotherapies have been developed for antiviral agent-refractory cytomegalovirus (CMV) disease after stem cell transplantation (SCT). However, the application of such strategies is limited, particularly in terms of need for donor cooperation regarding blood sampling and inaccessibility in the setting of cord blood transplantation. Herein, we describe the first successful treatment of antiviral agent-refractory CMV enteritis after allogeneic SCT by the infusion of ex vivo-expanded donor-derived CD4(+) lymphocytes obtained from the recipient's peripheral blood.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , Citomegalovirus/isolamento & purificação , Enterite/tratamento farmacológico , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , Doadores de Sangue , Citomegalovirus/fisiologia , Infecções por Citomegalovirus/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Transplante Homólogo/efeitos adversos , Ativação Viral
12.
Phys Chem Chem Phys ; 18(48): 33047-33052, 2016 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-27886322

RESUMO

The structural, magnetic and electronic properties of 2D VX2 (X = S, Se) monolayers and graphene/VX2 heterostructures were studied using a DFT+U approach. It was found that the stability of the 1T phases of VX2 monolayers is linked to strong electron correlation effects. The study of vertical junctions comprising of graphene and VX2 monolayers demonstrated that interlayer interactions lead to the formation of strong spin polarization of both graphene and VX2 fragments while preserving the linear dispersion of graphene-originated bands. It was found that the insertion of Mo atoms between the layers leads to n-doping of graphene with a selective transformation of graphene bands keeping the spin-down Dirac cone intact.

13.
J Clin Pediatr Dent ; 40(6): 496-502, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27805893

RESUMO

OBJECTIVE: Most cases of hypophosphatasia (HPP) exhibit early loss of primary teeth. Results of micro-computed tomography (micro-CT) analysis of teeth with HPP have not yet been reported. The purpose of the present study was to describe the size and mineral density distribution and mapping of exfoliated teeth with HPP using micro CT. STUDY DESIGN: Seven exfoliated teeth were obtained from a patient with HPP. Exfoliated teeth sizes were measured on micro CT images and mineral densities of the mandibular primary central incisors were determined. RESULTS: Partial dentures were fabricated for the patient to replace the eight primary teeth which had exfoliated. Most primary teeth sizes were within the normal range. The mean values of enamel and dentin mineral densities in teeth with HPP were 1.35 and 0.88 g/cm3, respectively, in the mandibular primary central incisors. CONCLUSION: Mineral density distribution and mapping revealed that the values in teeth with HPP were lower than the homonymous teeth controls in all regions from the crown to apex. Furthermore, it was demonstrated that the differences between HPP and controls were larger on the crown side and the differences tended to converge on the apex side. These results suggested that the present patient showed mild hypomineralization in the primary dentition.


Assuntos
Hipofosfatasia/patologia , Calcificação de Dente/fisiologia , Dente Decíduo/patologia , Esmalte Dentário/patologia , Dentina/patologia , Humanos , Hipofosfatasia/metabolismo , Processamento de Imagem Assistida por Computador/métodos , Lactente , Masculino , Minerais/análise , Odontometria/métodos , Colo do Dente/patologia , Coroa do Dente/patologia , Esfoliação de Dente , Dente Decíduo/química , Microtomografia por Raio-X/métodos
14.
Diabetes Obes Metab ; 17(8): 800-4, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25930989

RESUMO

The aim of the present study was to determine the effects of luseogliflozin on 24-h glucose levels, assessed by continuous glucose monitoring, and on pharmacodynamic variables measured throughout the day. In this double-blind, placebo-controlled, crossover study, 37 patients with type 2 diabetes mellitus inadequately controlled with diet and exercise were randomized into two groups. Patients in each group first received luseogliflozin then placebo for 7 days each, or vice versa. After 7 days of treatment, the mean 24-h glucose level was significantly lower with luseogliflozin than with placebo [mean (95% confidence interval) 145.9 (134.4-157.5) mg/dl vs 168.5 (156.9-180.0) mg/dl; p < 0.001]. The proportion of time spent with glucose levels ≥70 to ≤180 mg/dl was significantly greater with luseogliflozin than with placebo [median (interquartile range) 83.2 (67.7-96.5)% vs 71.9 (46.9-83.3)%; p < 0.001] without inducing hypoglycaemia. The decrease in glucose levels was accompanied by reductions in serum insulin levels throughout the day.


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/farmacologia , Sorbitol/análogos & derivados , Glicemia/análise , Automonitorização da Glicemia/métodos , Estudos Cross-Over , Diabetes Mellitus Tipo 2/sangue , Método Duplo-Cego , Humanos , Hipoglicemia/induzido quimicamente , Japão , Refeições , Período Pós-Prandial/efeitos dos fármacos , Sorbitol/farmacologia
15.
Lett Appl Microbiol ; 60(4): 400-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25580646

RESUMO

UNLABELLED: Microcystis aeruginosa forms toxic cyanobacterial blooms throughout the world where its infectious phages are thought to influence host population dynamics. To assess the cyanophage impact on the host dynamics, we previously monitored Ma-LMM01-type phage abundance using a real-time PCR with a primer set designed based on the sequence of Microcystis phage Ma-LMM01; and we estimated the phage-infected host cell abundance. However, a recent study shows the Ma-LMM01 g91 gene sequence belongs to the smallest group, group III, of the three genotype groups, suggesting Ma-LMM01-type phage abundance was underestimated. Therefore, to re-evaluate the effect of Ma-LMM01-type phages on their hosts, we monitored the abundance of Ma-LMM01-type phages using real-time PCR with a new primer set designed based on the sequences of genotype groups I-III. We found phage abundance between 10(3) and 10(4) ml(-1) using the new primer set in samples where previously these phages were not detected using the old primer set. The frequency of Ma-LMM01-type phage-infected cells to Ma-LMM01-type phage-susceptible host cells may be as high as 30%, suggesting the phages may occasionally affect not only shifts in the genetic composition but also the dynamics of Ma-LMM01-type phage-susceptible host populations. SIGNIFICANCE AND IMPACT OF THE STUDY: Phages are one of the factors that may control the ecology of their host blooms. Therefore, it is essential to estimate phage abundance to understand phage impact on host populations. A real-time PCR assay was improved to detect a larger range of Microcystis cyanophages in natural surroundings where no phages were detected using a previous method by re-designing a new primer set based on sequences from three Ma-LMM01-type phage genetic groups. The new method allows us to determine the distribution, dynamics and infection cycle of the phage to help understand the interaction between the phages and the hosts.


Assuntos
Bacteriófagos/genética , Microcystis/virologia , Lagoas/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sequência de Bases , Genótipo , Microcystis/crescimento & desenvolvimento , Dados de Sequência Molecular
16.
J Clin Pediatr Dent ; 39(4): 322-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26161602

RESUMO

OBJECTIVE: Abused children have been reported to have low self-esteem. The aim of this study was to investigate the effects of dental intervention on self-esteem, oral condition, and concern for oral health in abused children admitted to a child protection service facility. STUDY DESIGN: We examined the oral condition of 65 children (34 boys, 31 girls; aged 2-15 years), instructed them in tooth-brushing. Self-esteem was examined using Pope's five-scale test for children. Before discharge, the children completed questionnaires on concern about their oral health. RESULTS: The findings revealed the reasons for admission were child abuse and neglect (n=45), domestic violence against the mother (n= 20), special needs (n=11), delinquency (n=7), school refusal (n=2), and other reasons (n=3). Thirty-five of the 65 residents (54%) needed treatment for caries. Of these, 24 (69%) were abused children and 11 (31%) were admitted due to other reasons. Mean self-esteem score differed significantly between the resident children (n=43) and an outpatient control group (n=102) (59.16±14.54 vs 73.92±16.81, respectively; p<0.01). CONCLUSION: Although the abused children had low self-esteem, after dental intervention, positive answers regarding oral health were obtained. The findings suggest that dental interventions might be effective for helping to improve the self-esteem of abused children.


Assuntos
Adolescente Institucionalizado/psicologia , Maus-Tratos Infantis/psicologia , Criança Institucionalizada/psicologia , Saúde Bucal , Autoimagem , Adolescente , Atitude Frente a Saúde , Criança , Pré-Escolar , Cárie Dentária/terapia , Crianças com Deficiência/psicologia , Violência Doméstica , Feminino , Comportamentos Relacionados com a Saúde , Educação em Saúde Bucal , Humanos , Delinquência Juvenil , Masculino , Avaliação das Necessidades , Saúde Bucal/educação , Escovação Dentária/psicologia
17.
J Phys Chem A ; 118(50): 11744-50, 2014 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-25420099

RESUMO

Bromoiodomethane, CH2BrI, is a molecule of natural origin emitted in significant amount into the marine boundary layer. It can easily be decomposed by solar radiation, releasing Br and I atoms in the troposphere, which in turn impacts the atmospheric chemistry. Spectroscopy is an invaluable tool to monitor species present in the atmosphere. Since no high-resolution spectroscopic studies are available for this dihalomethane, we have investigated the rotational spectra of the two bromine isotopologues of CH2BrI in its vibrational ground state in the microwave and millimeter-wave regions. Transitions of b-type have been recorded by Fourier transform microwave spectroscopy below 25 GHz while both a- and b-type spectral lines have been measured below 230 GHz. Observed transitions correspond to energy levels with J ≤ 132 and Ka ≤ 14. Molecular constants including those describing the nuclear quadrupole coupling tensors for (79)Br, (81)Br, and (127)I were accurately determined from the least-squares analysis of a total of 1873 distinct transition frequencies (of which 943 belong to the CH2(79)BrI isotopologue). An experimental (r0) structure of the title species has been derived from the two sets of rotational constants.

18.
Skin Res Technol ; 20(2): 155-63, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23800248

RESUMO

BACKGROUND: A quantitative understanding of the histological alteration of the skin is important for assessing the severity of photoaging. METHODS: We performed Elastica-van Gieson staining and immunohistochemistry for decorin on 34 facial skin sections. We evaluated the alteration of collagen fibers and decorin (a modulator for collagen fibrillogenesis), according to the 5 grades of morphological change in elastic fibers that was established by Kligman (1969). The objectivity of a stage (Stages I-VI), which was established in this study, was evaluated using weighted kappa statistical analysis based on the degree of agreement in stage determination by 11 observers using a blind procedure. Correlation between the crow's-feet-area wrinkles grades of another 26 women and stages was also analyzed. RESULTS: The initial alteration of elastic fibers was observed in the deep dermis. Decorin was not detected in very severely altered skin. Based on the combination of changes in the elastic fibers, collagenic fibers, and decorin, skin tissues were categorized into 6 stages according to severity. The statistical analysis showed almost perfect agreement between observers. Significant positive correlation between stages and wrinkle scores was found. CONCLUSIONS: We propose a new objective histological scale that is useful for assessing the severity of photoaging.


Assuntos
Decorina/metabolismo , Colágenos Fibrilares/metabolismo , Envelhecimento da Pele/fisiologia , Pele/citologia , Pele/metabolismo , Escala Visual Analógica , Idoso , Biomarcadores/metabolismo , Dermoscopia/métodos , Tecido Elástico/citologia , Tecido Elástico/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Pele/efeitos da radiação , Envelhecimento da Pele/efeitos da radiação
19.
Database (Oxford) ; 20242024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38581360

RESUMO

When the scientific dataset evolves or is reused in workflows creating derived datasets, the integrity of the dataset with its metadata information, including provenance, needs to be securely preserved while providing assurances that they are not accidentally or maliciously altered during the process. Providing a secure method to efficiently share and verify the data as well as metadata is essential for the reuse of the scientific data. The National Science Foundation (NSF) funded Open Science Chain (OSC) utilizes consortium blockchain to provide a cyberinfrastructure solution to maintain integrity of the provenance metadata for published datasets and provides a way to perform independent verification of the dataset while promoting reuse and reproducibility. The NSF- and National Institutes of Health (NIH)-funded Neuroscience Gateway (NSG) provides a freely available web portal that allows neuroscience researchers to execute computational data analysis pipeline on high performance computing resources. Combined, the OSC and NSG platforms form an efficient, integrated framework to automatically and securely preserve and verify the integrity of the artifacts used in research workflows while using the NSG platform. This paper presents the results of the first study that integrates OSC-NSG frameworks to track the provenance of neurophysiological signal data analysis to study brain network dynamics using the Neuro-Integrative Connectivity tool, which is deployed in the NSG platform. Database URL: https://www.opensciencechain.org.


Assuntos
Neurociências , Publicações , Reprodutibilidade dos Testes , Bases de Dados Factuais , Metadados
20.
Strahlenther Onkol ; 189(4): 335-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23443610

RESUMO

BACKGROUND AND PURPOSE: Bloom syndrome is a DNA repair disorder that is hypersensitive to radiotherapy. We describe the first case in which proton beam therapy (PBT) was used in a patient with Bloom syndrome to treat oropharyngeal cancer. PATIENTS AND METHODS: The patient was a 32-year-old woman with Bloom syndrome who was diagnosed with oropharyngeal cancer staged as T2N2bM0 poorly differentiated squamous cell carcinoma. The primary tumor was located on the right tongue base and extended to the right lateral pharyngeal wall. Several right upper region lymph nodes were positive for metastases. RESULTS: We selected PBT in anticipation of dose reduction to normal tissue. The clinical target volume was defined as the area of the primary tumor and lymph node metastases plus an 8-mm margin. After treatment with 36 GyE (Gray equivalent) in 20 fractions (4-5 fractions per week), dietary intake was decreased by mucositis and intravenous hyperalimentation was started. Termination of treatment for 2.5 weeks was required to relieve mucositis. Administration of 59.4 GyE in 33 fractions markedly reduced the size of the primary tumor, but also caused moderate mucositis that required termination of PBT. One month later, lung metastases and breast cancer developed and the patient died 9 months after PBT. At this time the reduction in size of the primary tumor was maintained without severe late toxicity. CONCLUSION: We obtained almost complete response for a radiosensitive patient with a deficiency of DNA repair, indicating the excellent dose concentration of proton beam therapy.


Assuntos
Síndrome de Bloom/radioterapia , Carcinoma de Células Escamosas/radioterapia , Fracionamento da Dose de Radiação , Neoplasias Orofaríngeas/radioterapia , Terapia com Prótons/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Adulto , Carcinoma de Células Escamosas/patologia , Feminino , Seguimentos , Humanos , Metástase Linfática/patologia , Metástase Linfática/radioterapia , Imageamento por Ressonância Magnética , Mucosa Bucal/efeitos da radiação , Mucosite/etiologia , Estadiamento de Neoplasias , Neoplasias Orofaríngeas/patologia , Terapia com Prótons/efeitos adversos , Lesões por Radiação/etiologia , Dosagem Radioterapêutica
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