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1.
Phys Rev Lett ; 132(24): 241803, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38949341

RESUMO

We report a search for time variations of the solar ^{8}B neutrino flux using 5804 live days of Super-Kamiokande data collected between May 31, 1996, and May 30, 2018. Super-Kamiokande measured the precise time of each solar neutrino interaction over 22 calendar years to search for solar neutrino flux modulations with unprecedented precision. Periodic modulations are searched for in a dataset comprising five-day interval solar neutrino flux measurements with a maximum likelihood method. We also applied the Lomb-Scargle method to this dataset to compare it with previous reports. The only significant modulation found is due to the elliptic orbit of the Earth around the Sun. The observed modulation is consistent with astronomical data: we measured an eccentricity of (1.53±0.35)%, and a perihelion shift of (-1.5±13.5) days.

2.
Phys Rev Lett ; 130(5): 051801, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36800472

RESUMO

The KamLAND-Zen experiment has provided stringent constraints on the neutrinoless double-beta (0νßß) decay half-life in ^{136}Xe using a xenon-loaded liquid scintillator. We report an improved search using an upgraded detector with almost double the amount of xenon and an ultralow radioactivity container, corresponding to an exposure of 970 kg yr of ^{136}Xe. These new data provide valuable insight into backgrounds, especially from cosmic muon spallation of xenon, and have required the use of novel background rejection techniques. We obtain a lower limit for the 0νßß decay half-life of T_{1/2}^{0ν}>2.3×10^{26} yr at 90% C.L., corresponding to upper limits on the effective Majorana neutrino mass of 36-156 meV using commonly adopted nuclear matrix element calculations.

3.
Phys Rev Lett ; 130(3): 031802, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36763398

RESUMO

We report a search for cosmic-ray boosted dark matter with protons using the 0.37 megaton×years data collected at Super-Kamiokande experiment during the 1996-2018 period (SKI-IV phase). We searched for an excess of proton recoils above the atmospheric neutrino background from the vicinity of the Galactic Center. No such excess is observed, and limits are calculated for two reference models of dark matter with either a constant interaction cross section or through a scalar mediator. This is the first experimental search for boosted dark matter with hadrons using directional information. The results present the most stringent limits on cosmic-ray boosted dark matter and exclude the dark matter-nucleon elastic scattering cross section between 10^{-33}cm^{2} and 10^{-27}cm^{2} for dark matter mass from 1 MeV/c^{2} to 300 MeV/c^{2}.

5.
BJOG ; 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37156239

RESUMO

OBJECTIVE: To examine prevalence of novel newborn types among 541 285 live births in 23 countries from 2000 to 2021. DESIGN: Descriptive multi-country secondary data analysis. SETTING: Subnational, population-based birth cohort studies (n = 45) in 23 low- and middle-income countries (LMICs) spanning 2000-2021. POPULATION: Liveborn infants. METHODS: Subnational, population-based studies with high-quality birth outcome data from LMICs were invited to join the Vulnerable Newborn Measurement Collaboration. We defined distinct newborn types using gestational age (preterm [PT], term [T]), birthweight for gestational age using INTERGROWTH-21st standards (small for gestational age [SGA], appropriate for gestational age [AGA] or large for gestational age [LGA]), and birthweight (low birthweight, LBW [<2500 g], nonLBW) as ten types (using all three outcomes), six types (by excluding the birthweight categorisation), and four types (by collapsing the AGA and LGA categories). We defined small types as those with at least one classification of LBW, PT or SGA. We presented study characteristics, participant characteristics, data missingness, and prevalence of newborn types by region and study. RESULTS: Among 541 285 live births, 476 939 (88.1%) had non-missing and plausible values for gestational age, birthweight and sex required to construct the newborn types. The median prevalences of ten types across studies were T+AGA+nonLBW (58.0%), T+LGA+nonLBW (3.3%), T+AGA+LBW (0.5%), T+SGA+nonLBW (14.2%), T+SGA+LBW (7.1%), PT+LGA+nonLBW (1.6%), PT+LGA+LBW (0.2%), PT+AGA+nonLBW (3.7%), PT+AGA+LBW (3.6%) and PT+SGA+LBW (1.0%). The median prevalence of small types (six types, 37.6%) varied across studies and within regions and was higher in Southern Asia (52.4%) than in Sub-Saharan Africa (34.9%). CONCLUSIONS: Further investigation is needed to describe the mortality risks associated with newborn types and understand the implications of this framework for local targeting of interventions to prevent adverse pregnancy outcomes in LMICs.

6.
Clin Radiol ; 77(9): e689-e696, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35778295

RESUMO

AIM: To assess the utility of dynamic chest radiography (DCR) during the preoperative evaluation of pleural adhesions. MATERIALS AND METHODS: Sequential chest radiographs of 146 patients with lung cancer were acquired during forced respiration using a DCR system. The presence of pleural adhesions and their grades were determined by retrospective surgery video assessment (absent: 121, present: 25). The maximum inspiration to expiration lung area ratio was used as an index for air intake volume. A ratio of ≥0.65 was regarded as insufficient respiration. Two radiologists assessed the images for pleural adhesions based on motion findings. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were compared for each adhesion grade and patient group (patients with sufficient/insufficient respiration). Pearson's chi-squared test compared the group. Statistical significance was set at p<0.05. RESULTS: DCR correctly identified 22/25 patients with pleural adhesions, with 20 false-positive results (sensitivity, 88%; specificity, 83.5%; PPV, 52.4%; NPV, 97.12%). Although the diagnostic performances for the various adhesion grades were similar, specificity in patients with sufficient respiration increased to 93.9% (31/33), identifying all cases except for those with loose adhesions. CONCLUSIONS: DCR images revealed restricted and/or distorted motions in lung structures and structural tension in patients with pleural adhesions. DCR could be a useful technique for routine preoperative evaluation of pleural adhesions. Further development of computerised methods can assist in the quantitative assessment of abnormal motion findings.


Assuntos
Neoplasias Pulmonares , Doenças Pleurais , Humanos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/diagnóstico por imagem , Doenças Pleurais/diagnóstico por imagem , Radiografia , Estudos Retrospectivos , Sensibilidade e Especificidade , Aderências Teciduais/diagnóstico por imagem
7.
Histochem Cell Biol ; 156(4): 301-313, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34185148

RESUMO

The adenohypophysis is composed of the anterior and intermediate lobes (AL and IL), and secretes important hormones for growth, sexual development, metabolism, and reproduction. In the marginal cell layer (MCL) facing Rathke's cleft between the IL and AL, cluster of differentiation (CD) 9-, CD81-, S100ß-, and SOX2-quadruple positive (CD9/CD81/S100ß/SOX2-positive) cells in the adult IL are settled as tissue-resident stem/progenitor cells supplying hormone-producing cells to the AL. However, it is unclear how CD9/CD81/S100ß/SOX2-positive cells in the IL-side MCL migrate into the AL across Rathke's cleft. In the present study, we performed chimeric pituitary tissue culture using S100ß/GFP-transgenic rats and Wistar rats, and traced the footprint of S100ß/GFP-expressing cells. We detected IL-side S100ß/GFP-expressing cells in the AL tissue, demonstrating that these cells migrate from the IL to the AL. However, the cells failed to migrate in the opposite direction. Consistently, scanning electron microscopic analysis revealed well-developed cytoplasmic protrusions in the IL-side MCL, but not in the AL-side MCL, suggesting that IL-side CD9/CD81/S100ß/SOX2-positive cells had higher migratory activity. We also searched for a specific marker for IL-side CD9/CD81/S100ß/SOX2-positive cells and identified tetraspanin 1 (TSPAN1) from microarray analysis. Downregulation of Tspan1 by specific siRNA impaired cell migration and significantly reduced expression of snail family transcriptional repressor 2 (Slug), a marker of epithelial-mesenchymal transition (EMT). Therefore, CD9/CD81/S100ß/SOX2-positive cells in the IL-side MCL can be stem/progenitor cells that provide stem/progenitor cells to the AL-side MCL via SLUG-mediated EMT and cell migration.


Assuntos
Células Endócrinas/metabolismo , Adeno-Hipófise/metabolismo , Tetraspanina 29/metabolismo , Animais , Movimento Celular , Masculino , Ratos , Ratos Wistar
8.
Reproduction ; 160(2): 205-215, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32438343

RESUMO

The existence of cytoplasmic passages between germ cells and their potential function in the control of the spermatogenic process has long been an intriguing question. Evidence of the important role of such structures, known as intercellular bridges (ICB), in spermatogenesis has been implicated by the failure of spermatogenesis in testis-expressed gene 14 (Tex14) mutant mice, which lack the ICBs, to progress past the pachytene spermatocyte stage. Using these Tex14 mutants, the present study evaluated, for the first time, the behavior and synchrony of the spermatogonial lineage in the absence of ICBs. Our data suggest that the absence of these cytoplasmic connections between cells affects the expansion of the undifferentiated type A (Aundiff) spermatogonia compartment and their transition to A1, resulting in a significant numerical reduction of differentiating A1 spermatogonia, but did not interfere with cell amplification during subsequent mitotic steps of differentiating spermatogonia from A1 through intermediate (In). However, beginning at the type B spermatogonia, the synchrony of differentiation was impaired as some cells showed delayed differentiation compared to their behavior in a normal seminiferous epithelium cycle. Thus although spermatogonial development is able to proceed, in the absence of ICBs in Tex14-/- mutants, the yield of cells, specific steps of differentiation, the synchrony of the cell kinetics, and the subsequent progression in meiosis are quantitatively lower than normal.


Assuntos
Comunicação Celular , Diferenciação Celular , Meiose , Epitélio Seminífero/patologia , Espermatogênese , Espermatogônias/patologia , Fatores de Transcrição/fisiologia , Animais , Proliferação de Células , Citoplasma , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Epitélio Seminífero/metabolismo , Espermatogônias/metabolismo
9.
Phys Rev Lett ; 122(19): 192501, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31144924

RESUMO

We present a precision analysis of the ^{136}Xe two-neutrino ßß electron spectrum above 0.8 MeV, based on high-statistics data obtained with the KamLAND-Zen experiment. An improved formalism for the two-neutrino ßß rate allows us to measure the ratio of the leading and subleading 2νßß nuclear matrix elements (NMEs), ξ_{31}^{2ν}=-0.26_{-0.25}^{+0.31}. Theoretical predictions from the nuclear shell model and the majority of the quasiparticle random-phase approximation (QRPA) calculations are consistent with the experimental limit. However, part of the ξ_{31}^{2ν} range allowed by the QRPA is excluded by the present measurement at the 90% confidence level. Our analysis reveals that predicted ξ_{31}^{2ν} values are sensitive to the quenching of NMEs and the competing contributions from low- and high-energy states in the intermediate nucleus. Because these aspects are also at play in neutrinoless ßß decay, ξ_{31}^{2ν} provides new insights toward reliable neutrinoless ßß NMEs.

10.
Eur J Neurol ; 26(9): 1205-1211, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30980575

RESUMO

BACKGROUND AND PURPOSE: Corticobasal syndrome (CBS) is pathologically characterized by tau deposits in neuronal and glial cells and by reactive astrogliosis. In several neurodegenerative disorders, 18 F-THK5351 has been observed to bind to reactive astrocytes expressing monoamine oxidase B. In this study, the aim was to investigate the progression of disease-related pathology in the brains of patients with CBS using positron emission tomography with 18 F-THK5351. METHODS: Baseline and 1-year follow-up imaging were acquired using magnetic resonance imaging and positron emission tomography with 18 F-THK5351 in 10 subjects: five patients with CBS and five age-matched normal controls (NCs). RESULTS: The 1-year follow-up scan images revealed that 18 F-THK5351 retention had significantly increased in the superior parietal gyrus of the patients with CBS compared with the NCs. The median increases in 18 F-THK5351 accumulation in the patients with CBS were 6.53% in the superior parietal gyrus, 4.34% in the precentral gyrus and 4.33% in the postcentral gyrus. In contrast, there was no significant increase in the regional 18 F-THK5351 retention in the NCs. CONCLUSIONS: Longitudinal increases in 18 F-THK5351 binding can be detected over a short interval in the cortical sites of patients with CBS. A monoamine oxidase B binding radiotracer could be useful in monitoring the progression of astrogliosis in CBS.


Assuntos
Aminopiridinas , Doenças dos Gânglios da Base/diagnóstico por imagem , Progressão da Doença , Tomografia por Emissão de Pósitrons , Quinolinas , Compostos Radiofarmacêuticos , Tauopatias/diagnóstico por imagem , Idoso , Aminopiridinas/farmacocinética , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Quinolinas/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética
11.
Pharmazie ; 74(2): 120-124, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30782263

RESUMO

Aim of the study: Here, we investigated the risk factors for decreased teicoplanin plasma trough concentrations relative to the initial dosing in critically ill patients. Patients and methods: Data obtained from 80 eligible critically ill patients who received intravenous teicoplanin were retrospectively analyzed. Risk factors for decreases in teicoplanin trough concentrations 72 h after administration of teicoplanin of more than 30% relative to predicted concentrations based on initial dosing setting were identified by logistic regression analysis. Results: Although prediction trough concentration and total dose of two days no significant differences were seen between the variation group and the non-variation group, actual trough concentration was significantly different between two groups (19.9±5.6 µg/ml vs 10.3±2.2 µg/ml, p < 0.001). In multivariate analysis, serum albumin ≤ 2.2 mg/dl (odds ratio [OR] = 3.003, 95% CI 1.072-8.408; p = 0.036) and SOFA score ≥ 9 (OR = 3.498, 95% CI 1.171-10.450; p = 0.025) were significant risk factors for decreased teicoplanin plasma trough concentrations. Conclusion: In critically ill patients, high SOFA score and low serum albumin were risk factors for decreased teicoplanin plasma trough concentration during initial dosing.


Assuntos
Antibacterianos/sangue , Infecções/sangue , Infecções/tratamento farmacológico , Teicoplanina/sangue , Administração Intravenosa , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/administração & dosagem , Estado Terminal , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Teicoplanina/administração & dosagem , Adulto Jovem
12.
Phys Rev Lett ; 120(8): 083401, 2018 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-29543028

RESUMO

We report spectroscopic observation of Rydberg polarons in an atomic Bose gas. Polarons are created by excitation of Rydberg atoms as impurities in a strontium Bose-Einstein condensate. They are distinguished from previously studied polarons by macroscopic occupation of bound molecular states that arise from scattering of the weakly bound Rydberg electron from ground-state atoms. The absence of a p-wave resonance in the low-energy electron-atom scattering in Sr introduces a universal behavior in the Rydberg spectral line shape and in scaling of the spectral width (narrowing) with the Rydberg principal quantum number, n. Spectral features are described with a functional determinant approach (FDA) that solves an extended Fröhlich Hamiltonian for a mobile impurity in a Bose gas. Excited states of polyatomic Rydberg molecules (trimers, tetrameters, and pentamers) are experimentally resolved and accurately reproduced with a FDA.

13.
Lupus ; 27(10): 1636-1643, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29954283

RESUMO

Objective The objective of this study is to investigate the effectiveness of discontinuation of risedronate for patients with systemic lupus erythematosus (SLE) treated with glucocorticoid (GC). Methods The participants were patients with SLE treated with prednisolone (PSL) ≥ 2 mg/day and risedronate for at least three years. Lumbar spine and total hip bone mineral density (BMD) measurements were taken at baseline and 24 and 48 weeks after discontinuation of risedronate, and bone turnover markers were evaluated at baseline, 12, 24, 36, and 48 weeks. Results A total of 36 patients were enrolled, 25 of whom discontinued risedronate. The mean age was 46.8 ± 11.2 years, and 23 were female. The mean duration of GC treatment was 14.8 ± 11.4 years, the mean dose of PSL was 7.8 ± 3.9 mg/day, and the mean duration of risedronate was 5.8 ± 2.4 years. Seventeen patients showed decreased lumbar spine BMD at 48 weeks after discontinuation of risedronate, with a mean lumbar spine lumbar decrease of 1.42% ± 3.20% ( p = 0.034); 17 patients (71%) showed a decreased total hip BMD at 48 weeks after discontinuation of risedronate, with a mean total hip BMD decrease of 0.99% ± 2.10% ( p = 0.021). Serum tartrate-resistant acid phosphatase 5b (TRACP-5b) ≥ 309 mU/dl at baseline was a risk factor for decreased total hip BMD at 48 weeks compared with serum TRACP-5b < 309 mU/dl (56% vs 0%, p = 0.0098). One patient developed a clinical fracture of the lumbar spine at 20 weeks. Conclusions Discontinuation of risedronate treatment in patients with SLE who had received GC therapy led to decreases in lumbar spine and total hip BMD, particularly in patients with high baseline serum TRACP-5b levels.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Densidade Óssea/efeitos dos fármacos , Glucocorticoides/administração & dosagem , Vértebras Lombares/efeitos dos fármacos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Ossos Pélvicos/efeitos dos fármacos , Prednisolona/administração & dosagem , Ácido Risedrônico/administração & dosagem , Adulto , Biomarcadores/sangue , Esquema de Medicação , Feminino , Glucocorticoides/efeitos adversos , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiopatologia , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/diagnóstico , Masculino , Pessoa de Meia-Idade , Osteoporose/sangue , Osteoporose/induzido quimicamente , Osteoporose/diagnóstico por imagem , Osteoporose/fisiopatologia , Ossos Pélvicos/diagnóstico por imagem , Ossos Pélvicos/fisiopatologia , Prednisolona/efeitos adversos , Fatores de Proteção , Fatores de Risco , Fosfatase Ácida Resistente a Tartarato/sangue , Fatores de Tempo , Resultado do Tratamento
14.
Lupus ; 27(14): 2245-2252, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30394835

RESUMO

OBJECTIVES: We investigated the efficacy and safety of tacrolimus (TAC) by monitoring its serum concentration for mothers and infants in pregnant patients with systemic lupus erythematosus (SLE). METHODS: We measured trough concentrations of TAC in 25 pregnant patients with SLE to assess influence of TAC on the disease activity. Additionally, we measured the concentrations of TAC in umbilical arterial blood, breast milk, and breastfed infants to investigate the safety of TAC for the mothers and infants. RESULTS: The trough concentrations of TAC in the mothers significantly decreased in the second trimester as compared with those before pregnancy. However, the decrease in the trough concentrations of TAC did not lead to the deterioration of SLE. When examined, the doses of TAC were significantly lower in the second trimester and postpartum in the deteriorating group than those in the non-deteriorating group. There were no adverse events by TAC in mothers and fetuses. The concentrations of TAC in the umbilical cord blood were lower than those in the maternal blood. The relative infant dose in breastfed infants of TAC was < 1%. The level of TAC in infant bloods was below detectable limits. CONCLUSION: These findings suggest that TAC is one of the most effective and safest immunosuppressive drugs for use in pregnant patients with SLE.


Assuntos
Imunossupressores/uso terapêutico , Lactação , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Tacrolimo/uso terapêutico , Adulto , Aleitamento Materno , Feminino , Sangue Fetal/química , Humanos , Imunossupressores/sangue , Lactente , Recém-Nascido , Japão , Leite Humano/química , Gravidez , Índice de Gravidade de Doença , Tacrolimo/sangue
16.
Phys Rev Lett ; 118(5): 052701, 2017 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-28211732

RESUMO

The cross sections of the ^{7}Be(n,α)^{4}He reaction for p-wave neutrons were experimentally determined at E_{c.m.}=0.20-0.81 MeV slightly above the big bang nucleosynthesis (BBN) energy window for the first time on the basis of the detailed balance principle by measuring the time-reverse reaction. The obtained cross sections are much larger than the cross sections for s-wave neutrons inferred from the recent measurement at the n_TOF facility in CERN, but significantly smaller than the theoretical estimation widely used in the BBN calculations. The present results suggest the ^{7}Be(n,α)^{4}He reaction rate is not large enough to solve the cosmological lithium problem, and this conclusion agrees with the recent result from the direct measurement of the s-wave cross sections using a low-energy neutron beam and the evaluated nuclear data library ENDF/B-VII.1.

17.
Parasite Immunol ; 39(12)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29072334

RESUMO

Interleukin-12 (IL-12) plays an important role in antigen-specific adaptive immunity against Plasmodium sporozoites, and this requirement allows for a new approach to developing an effective malaria vaccine. In this study, we examined whether IL-12 could enhance protective efficacy of a baculovirus-based malaria vaccine. For this aim, a baculoviral vector expressing murine IL-12 (mIL-12) under the control of CMV promoter (BES-mIL-12-Spider) and a baculoviral vector expressing Plasmodium falciparum circumsporozoite protein (PfCSP) with post-transcriptional regulatory element of woodchuck hepatitis virus (BDES-sPfCSP2-WPRE-Spider) were generated. BES-mIL-12-Spider produced bioactive IL-12 which activates splenocytes, resulting in induction of IFN-γ. When co-immunized with BES-mIL-12-Spider and BDES-sPfCSP2-WPRE-Spider, the mouse number for high IgG2a/IgG1 ratios and the geometric mean in this group were both increased as compared with those of the other groups, indicating a shift towards a Th1-type response following immunization with BES-mIL-12-Spider. Finally, immunization with BDES-sPfCSP2-WPRE-Spider plus BES-mIL-12-Spider had a higher protective efficacy (73%) than immunization with BDES-sPfCSP2-WPRE-Spider alone (30%) against challenge with transgenic Plasmodium berghei sporozoites expressing PfCSP. These results suggest that co-administration of IL-12 expressing baculoviral vector, instead of IL-12 cDNA, with viral-vectored vaccines provides a new feasible vaccine platform to enhance Th1-type cellular immune responses against Plasmodium parasites.


Assuntos
Anticorpos Antiprotozoários/imunologia , Interleucina-12/imunologia , Vacinas Antimaláricas/imunologia , Plasmodium berghei/imunologia , Plasmodium falciparum/imunologia , Proteínas de Protozoários/imunologia , Animais , Baculoviridae/genética , Linhagem Celular , Vetores Genéticos/genética , Células Hep G2 , Humanos , Imunoglobulina G/imunologia , Interferon gama/imunologia , Interleucina-12/biossíntese , Interleucina-12/genética , Camundongos , Plasmodium berghei/genética , Proteínas de Protozoários/biossíntese , Proteínas de Protozoários/genética , Esporozoítos/imunologia , Vacinação
18.
Nanotechnology ; 28(18): 185701, 2017 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-28290374

RESUMO

The thermal transport properties of random network, single-walled carbon nanotube (SWNT) films were assessed using Raman spectroscopy. Two types of SWNT films were investigated: single-layer and stacked. The single-layer films were fabricated by aerosol chemical vapour deposition and subsequent direct dry deposition, while the stacked films were prepared by placing the single-layer films on top of one another. The anisotropy of the network structures of each of these films was evaluated based on the angular dependence of the optical absorbance spectra. The results show that the anisotropy of the films decreases with increasing film thickness in the case of the single-layer films, and that the film anisotropy is preserved during the stacking process. The sheet thermal conductance is proportional to the SWNT area density in the case of stacked films, but is reduced with increasing thickness in the case of single-layer films. This effect is explained by a change in the network morphology from a two-dimensional anisotropic structure to the more isotropic structure. This work demonstrates the fabrication of low-density films with high sheet thermal conductance through the stacking of thin SWNT films.

19.
J Periodontal Res ; 52(6): 984-993, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28590058

RESUMO

BACKGROUND AND OBJECTIVE: Human periodontal ligament cells (HPDLCs) express transforming growth factor-ß1 (TGF-ß1) that regulates differentiation and proliferation, and plays key roles in homeostasis of PDL tissue. Transgelin is a cytoskeleton-associated protein with an Smad-binding element in its gene promoter region. In this study, we examined the localization and potential function of transgelin in PDL tissue and cells. MATERIAL AND METHODS: Microarray analysis of HPDLC lines (2-14, 2-23 and 2-52) was performed. Expression of transgelin in HPDLCs was examined by quantitative reverse transcription-polymerase chain reaction, immunofluorescence staining and western blot analysis. Effects of TGF-ß1 and its signaling inhibitor, SB431542, on transgelin expression in HPDLCs were examined by western blot analysis. The effects of transgelin knockdown by small interfering RNA (siRNA) on HPDLC proliferation stimulated by TGF-ß1 were assessed by WST-1 assay. RESULTS: In microarray and quantitative reverse transcription-polymerase chain reaction analyses, the expression levels of transgelin (TAGLN) in 2-14 and 2-23 cells, which highly expressed PDL markers such as periostin (POSTN), tissue non-specific alkaline phosphatase (ALPL), α-smooth muscle actin (ACTA2) and type I collagen A1 (COL1A1), was significantly higher than those in 2-52 cells that expressed PDL markers weakly. Immunohistochemical and immunofluorescence staining revealed expression of transgelin in rat PDL tissue and HPDLCs. In HPDLCs, TGF-ß1 treatment upregulated transgelin expression, whereas inhibition of the type 1 TGF-ß1 receptor by SB431542 suppressed this upregulation. Furthermore, TAGLN siRNA transfection did not promote the proliferation of HPDLCs treated with TGF-ß1. The expression levels of CCNA2 and CCNE1, which regulate DNA synthesis and mitosis through the cell cycle, were also not upregulated in HPDLCs transfected with TAGLN siRNA. CONCLUSION: Transgelin is expressed in PDL tissue and might have a role in HPDLC proliferation induced by TGF-ß1 stimulation.


Assuntos
Proteínas dos Microfilamentos/farmacologia , Proteínas Musculares/farmacologia , Ligamento Periodontal/efeitos dos fármacos , Fator de Crescimento Transformador beta/antagonistas & inibidores , Adulto , Benzamidas/farmacologia , Western Blotting , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Dioxóis/farmacologia , Feminino , Imunofluorescência , Humanos , Masculino , Proteínas dos Microfilamentos/fisiologia , Proteínas Musculares/fisiologia , Ligamento Periodontal/citologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise Serial de Tecidos , Fator de Crescimento Transformador beta/farmacologia , Adulto Jovem
20.
J Endocrinol Invest ; 40(4): 385-389, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27848228

RESUMO

INTRODUCTION: High DNA polymerase ß activity has been observed in the thyroid tissue of patients with Graves' disease (Nagasaka et al. in Metabolism 37:1051-1054, 1988). This fact aroused our interest in whether the alteration of DNA polymerase ß activity depends on DNA polymerase ß (DNA poly ß) mRNA levels, which may be modulated by thyroid-stimulating hormone (TSH) or thyroid-stimulating substances, i.e. TSH receptor antibody (TRAb). RESULT: Addition of TSH or TRAb to primary cultures of Graves' disease thyroid cells for 4 h led to no increase in DNA poly ß mRNA levels. In contrast, thyroid hormone synthesizing enzyme, peroxidase, mRNA levels increased fivefold after coculture with TSH and TRAb, even though DNA poly ß activity and mRNA levels are already significantly higher in Graves' disease thyroid tissues, compared with normal thyroid tissue. DISCUSSION: These results indicate that DNA poly ß expression in Graves' disease thyroid cells may be maximally activated or plateau in response to thyroid-stimulating immunoglobulins, or that the activation of to poly ß expression may occur via pathways other than the G protein and cyclic AMP system.


Assuntos
DNA Polimerase beta/genética , Doença de Graves/enzimologia , RNA Mensageiro/genética , Glândula Tireoide/enzimologia , Autoantígenos/genética , Northern Blotting , Células Cultivadas , Doença de Graves/genética , Doença de Graves/patologia , Humanos , Imunoglobulinas Estimuladoras da Glândula Tireoide/farmacologia , Iodeto Peroxidase/genética , Proteínas de Ligação ao Ferro/genética , Receptores da Tireotropina/imunologia , Glândula Tireoide/patologia , Hormônios Tireóideos/metabolismo , Tireotropina/farmacologia
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