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1.
Eur Radiol ; 28(5): 1929-1937, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29218614

RESUMO

OBJECTIVES: We aimed to determine whether high-resolution specimen-positron emission mammography (PEM) using fluorodeoxyglucose (18F-FDG) can reveal extension of breast cancer in breast-conserving surgery (BCS), and assess the safety of radiation exposure to medical staff. METHODS: Sixteen patients underwent positron emission tomography, and then BCS with intraoperative frozen section analysis on the same day. Resected specimens with remaining 18F-FDG accumulation were scanned by high-resolution PEM. At least 1 day after surgery, tumour extension was evaluated by three independent experienced readers and by binarized images from the specimen-PEM data. Intraoperative exposure of medical staff to 18F-FDG was measured. RESULTS: Specimen-PEM evaluations of binarized images and the three investigators detected all (100 %, 12/12) invasive lesions and 94.4 % (17/18) of in situ lesions using both methods. The positive predictive value of the accumulated lesions was 74.4 % (29/39) for the binarized images and 82.9 % (29/35) for the three investigators. Analysis of intraoperative frozen sections detected 100 % (2/2) of the margin-positive cases, also detected by both specimen-PEM evaluation methods with no false-positive margin cases. The mean exposure of the medical staff to 18F was 18 µSv. CONCLUSIONS: Specimen-PEM detected invasive and in situ lesions with high accuracy and allowable radiation exposure. KEY POINTS: • Specimen-PEM detected invasive and in situ lesions with high accuracy. • Specimen-PEM predicted complete resection with the same accuracy as frozen section analysis. • Breast-conserving surgery after fluorodeoxyglucose injection was performed with low medical staff exposure.


Assuntos
Neoplasias da Mama/diagnóstico , Fluordesoxiglucose F18/farmacologia , Mamografia/métodos , Mastectomia Segmentar/métodos , Tomografia por Emissão de Pósitrons/métodos , Idoso , Neoplasias da Mama/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Compostos Radiofarmacêuticos/farmacologia
2.
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.

3.
Phys Rev Lett ; 116(5): 052501, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26894705

RESUMO

A candidate resonant tetraneutron state is found in the missing-mass spectrum obtained in the double-charge-exchange reaction ^{4}He(^{8}He,^{8}Be) at 186 MeV/u. The energy of the state is 0.83±0.65(stat)±1.25(syst) MeV above the threshold of four-neutron decay with a significance level of 4.9σ. Utilizing the large positive Q value of the (^{8}He,^{8}Be) reaction, an almost recoilless condition of the four-neutron system was achieved so as to obtain a weakly interacting four-neutron system efficiently.

4.
Appl Opt ; 55(5): 1164-9, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26906392

RESUMO

We demonstrate frequency offset locking between two laser sources using a waveguide-type electro-optic modulator (EOM) with 10th-order sidebands for magneto-optical trapping of Fr atoms. The frequency locking error signal was successfully obtained by performing delayed self-homodyne detection of the beat signal between the repumping frequency and the 10th-order sideband component of the trapping light. Sweeping the trapping-light and repumping-light frequencies with keeping its frequency difference of 46 GHz was confirmed over 1 GHz by monitoring the Doppler absorption profile of I2. This technique enables us to search for a resonance frequency of magneto-optical trapping of Fr.

6.
Phys Rev Lett ; 115(10): 102501, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26382672

RESUMO

Differential cross sections of isoscalar and isovector spin-M1 (0(+)→1(+)) transitions are measured using high-energy-resolution proton inelastic scattering at E(p)=295 MeV on (24)Mg, (28)Si, (32)S, and (36)Ar at 0°-14°. The squared spin-M1 nuclear transition matrix elements are deduced from the measured differential cross sections by applying empirically determined unit cross sections based on the assumption of isospin symmetry. The ratios of the squared nuclear matrix elements accumulated up to E(x)=16 MeV compared to a shell-model prediction are 1.01(9) for isoscalar and 0.61(6) for isovector spin-M1 transitions, respectively. Thus, no quenching is observed for isoscalar spin-M1 transitions, while the matrix elements for isovector spin-M1 transitions are quenched by an amount comparable with the analogous Gamow-Teller transitions on those target nuclei.

8.
J Dairy Sci ; 98(4): 2533-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25648815

RESUMO

Difructose anhydride (DFA) III promotes the intestinal absorption of calcium via a paracellular pathway in rats. In dairy cows, DFA III reaches the duodenum without being degraded by ruminal bacteria and hence could be used to control hypocalcemia. The aims of the present study were to investigate the percentage of DFA III that appears in the duodenum of cows and to determine the effect of DFA III on calcium absorption from duodenal fluid. The first experiment was performed in 3 ruminally and duodenally cannulated dry Holstein cows in a 3 × 3 Latin square design. Each experimental period lasted 7 d. On the first day, the cows were ruminally fed one of the following treatments: 0 (DFA0), 50 (DFA50), or 100 (DFA100) g/d of DFA III, using cobalt-EDTA as a liquid phase marker. Difructose anhydride III was detected in duodenal fluid 1 h after feeding, and its concentration peaked 4 h after feeding, in a dose-dependent manner. The percentages of DFA III that appeared in the duodenum after the DFA50 and DFA100 treatments were 69.1 ± 7.0% and 67.9 ± 5.6%, respectively. The second experiment used the everted duodenal sacs of cattle (n = 7 in each group). Sacs were incubated in artificial mucosal fluid containing 1 mM DFA III or no DFA III (control) for 60 min with 100% O2 in a water bath at 37 °C. After incubation, the calcium concentration of the artificial serosal fluid in the everted sacs was measured. Calcium absorption was higher in the DFA III-treated group than in the control group (803 ± 161 and 456 ± 74 nmol/cm of sac, respectively). The above results demonstrate that approximately 70% of administered DFA III reached the duodenum of cows intact. Moreover, similar to its effects on calcium absorption in rats, DFA III promoted calcium absorption via a paracellular pathway in the duodenum of cows.


Assuntos
Cálcio da Dieta/metabolismo , Dissacarídeos/metabolismo , Absorção Intestinal/efeitos dos fármacos , Animais , Cálcio/metabolismo , Cálcio/farmacologia , Bovinos , Duodeno/metabolismo , Feminino , Conteúdo Gastrointestinal/efeitos dos fármacos , Ratos
9.
Opt Express ; 22(5): 6108-13, 2014 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-24663945

RESUMO

We demonstrate a compact 100 Gbit/s DP-QPSK receiver module that is only 18 mm (W) x 16 mm (D) x 2.8 mm (H). The module size is reduced by using a ball grid array (BGA) package with three-dimensional assembly technology and by applying a heterogeneous integrated PLC. Error-free DP-QPSK signal demodulation is successfully demonstrated.

10.
Phys Rev Lett ; 113(10): 102501, 2014 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-25238351

RESUMO

The direct 3α decay branch from the 02+ state at Ex=7.65 MeV in 12C, which is known as the Hoyle state, is considered to affect the triple-α reaction rate strongly and to give crucial information on its structure. We have performed a high-precision measurement of the 3α decay from this state using the 12C(12C,3α)12C reaction at E12C=110 MeV. The branching ratio of the direct 3α decay was under the detection limit in the present experiment. By comparing with Monte Carlo simulations for three decay mechanisms as the sequential decay through the ground state of ^{8}Be, the direct decay with equal energies of three α particles, and the direct decay to the phase space uniformly, we have obtained the upper limit of 0.2% on the direct 3α decay.

11.
Andrologia ; 46(5): 556-63, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23710595

RESUMO

Experimental autoimmune orchitis (EAO), comprising a breakdown of the testicular immune privilege, is one of the models of immunological male infertility. EAO is characterised by CD4 + T-cell-dependent lymphocytic inflammation and augmented delayed-type hypersensitivity (DTH) against testicular antigens. We previously established an EAO model in mice by immunisation with viable syngeneic testicular germ cells (TGC) alone. However, the sequential change of DTH during development of this EAO has not been analysed yet. In this study, the DTH response during TGC-induced EAO was investigated by the injection of syngeneic TGC protein into the ears of mice. The results showed that a significant DTH response was observed on injection of 20 µg TGC protein, but not on that of 0.2 or 2 µg TGC protein. Also, the level of the DTH response to 20 µg TGC protein was highly relevant to the pathology of EAO development. These results indicate that the DTH response on injection of 20 µg TGC protein into the ears of mice is effective for predicting the pathology of EAO development.


Assuntos
Hipersensibilidade Tardia , Espermatozoides/imunologia , Testículo/imunologia , Animais , Masculino , Camundongos , Testículo/citologia
12.
Sci Rep ; 14(1): 14552, 2024 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914593

RESUMO

We have reported that an environmental pollutant, cadmium, promotes cell death in the human renal tubular cells (RTCs) through hyperactivation of a serine/threonine kinase Akt. However, the molecular mechanisms downstream of Akt in this process have not been elucidated. Cadmium has a potential to accumulate misfolded proteins, and proteotoxicity is involved in cadmium toxicity. To clear the roles of Akt in cadmium exposure-induced RTCs death, we investigated the possibility that Akt could regulate proteotoxicity through autophagy in cadmium chloride (CdCl2)-exposed HK-2 human renal proximal tubular cells. CdCl2 exposure promoted the accumulation of misfolded or damaged proteins, the formation of aggresomes (pericentriolar cytoplasmic inclusions), and aggrephagy (selective autophagy to degrade aggresome). Pharmacological inhibition of Akt using MK2206 or Akti-1/2 enhanced aggrephagy by promoting dephosphorylation and nuclear translocation of transcription factor EB (TFEB)/transcription factor E3 (TFE3), lysosomal transcription factors. TFEB or TFE3 knockdown by siRNAs attenuated the protective effects of MK2206 against cadmium toxicity. These results suggested that aberrant activation of Akt attenuates aggrephagy via TFEB or TFE3 to facilitate CdCl2-induced cell death. Furthermore, these roles of Akt/TFEB/TFE3 were conserved in CdCl2-exposed primary human RTCs. The present study shows the molecular mechanisms underlying Akt activation that promotes cadmium-induced RTCs death.


Assuntos
Autofagia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Cádmio , Proteínas Proto-Oncogênicas c-akt , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Autofagia/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Linhagem Celular , Cádmio/toxicidade , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , Fosforilação/efeitos dos fármacos , Cloreto de Cádmio/toxicidade , Compostos Heterocíclicos com 3 Anéis/farmacologia , Túbulos Renais/metabolismo , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/citologia , Túbulos Renais/patologia
13.
Parasitology ; 140(5): 626-31, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23351616

RESUMO

Mucosal mast cells (MMC) play a crucial role in the expulsion of Strongyloides ratti adults from the small intestine of mice. We reported the large intestinal parasitism of S. ratti in rats, and there has been no report on MMC in the large intestine of the natural host. We studied kinetics of MMC, together with eosinophils, in the upper and lower small intestines, caecum and colon of infected rats. Two distinct phases of mastocytosis were revealed: one in the upper small intestine triggered by stimulation of 'ordinary' adults, and the other in the colon stimulated by 'immune-resistant' adults that started parasitizing the colon around 19 days post-infection. In all 4 intestinal sites, the MMC peaks were observed 5-7 days after the number of adult worms became the maximum and the height of MMC peaks appeared to be dependent on the number of parasitic adults, suggesting an important role played by worms themselves in the MMC buildup.


Assuntos
Eosinófilos/fisiologia , Intestinos/citologia , Mastócitos/fisiologia , Strongyloides ratti/fisiologia , Estrongiloidíase/veterinária , Animais , Intestinos/parasitologia , Masculino , Ratos , Ratos Wistar , Strongyloides ratti/imunologia , Estrongiloidíase/imunologia , Estrongiloidíase/patologia , Fatores de Tempo
14.
Int J Sports Med ; 34(4): 368-75, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23041964

RESUMO

Physical exercise has been shown to increase adult neurogenesis in the hippocampus and to enhance synaptic plasticity. It has been demonstrated that these neuroprotective effects can be observed following aerobic exercise. However, it remains unknown whether plasticity molecules, such as brain-derived neurotrophic factor (BDNF) and cyclic AMP response element-binding protein (CREB), are expressed in the hippocampus following resistance exercise. We applied voluntary progressive-resistance wheel exercise (RE) for 14 days, and measured BDNF and CREB in the hippocampus. The Morris water maze was also performed to estimate learning and memory. Furthermore, we measured RE effects on mammalian target of rapamycin (mTOR) and 70-kDa ribosomal protein S6 kinase (p70S6K) mediating muscle protein synthesis in the soleus. As a result, we found that RE enhanced cognition and elevated BDNF and CREB expressions in the hippocampus. Also, RE activated the mTOR-p70S6K signaling pathway in the soleus. We found that phosphorylated mTOR and p70S6K were significantly positively correlated with BDNF expression. Our results indicated that resistance exercise drove the protein synthesis signaling pathway in the soleus and enhanced hippocampal synaptic plasticity-related molecules. These results suggest the beneficial effects of resistance exercise on cognitive function.


Assuntos
Cognição/fisiologia , Condicionamento Físico Animal/métodos , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Hipocampo/metabolismo , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Fosforilação , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/metabolismo
16.
Phys Rev Lett ; 106(10): 105502, 2011 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-21469803

RESUMO

Resonant ultrasound spectroscopy has been used to follow elastic softening in SrTi(18)O3 in the frequency range ∼0.2-1 MHz. A dramatic softening of C44 occurs as the Curie temperature T(c) = 24 K is approached from above or below, which correlates with the development of a central peak in Raman and Brillouin spectra. This is attributed to strong coupling between the acoustic mode and the central peak mode. A weaker anomaly is seen in a resonance mode which is believed to be controlled by 1/2(C11-C12). Significant attenuation accompanies this softening and an additional dissipation peak has also been observed at ∼80-90 K. This extends earlier work by a factor of 150,000× from the 30 GHz regime and helps address the question as to whether the ferroelectricity is stimulated primarily by a soft mode into a homogeneous ground state or by clustering of rhombohedral nanoregions into an inhomogeneous ground state.

17.
Phys Rev Lett ; 107(6): 062502, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21902316

RESUMO

A benchmark experiment on (208)Pb shows that polarized proton inelastic scattering at very forward angles including 0° is a powerful tool for high-resolution studies of electric dipole (E1) and spin magnetic dipole (M1) modes in nuclei over a broad excitation energy range to test up-to-date nuclear models. The extracted E1 polarizability leads to a neutron skin thickness r(skin) = 0.156(-0.021)(+0.025) fm in (208)Pb derived within a mean-field model [Phys. Rev. C 81, 051303 (2010)], thereby constraining the symmetry energy and its density dependence relevant to the description of neutron stars.

18.
Curr Opin Cell Biol ; 11(5): 628-33, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10508648

RESUMO

Tight junctions (TJs) have been suggested to act both as barriers and fences, but lack of information on the constituents of TJ strands has hampered the direct assessment of these functions. Over the past year, our understanding of the molecular architecture of TJ strands has increased markedly and we are ready to experimentally examine how TJs are involved in their dual functions.


Assuntos
Transdução de Sinais , Junções Íntimas/metabolismo , Animais , Proteínas de Transporte/fisiologia , Moléculas de Adesão Celular/fisiologia , Guanilato Quinases , Humanos , Moléculas de Adesão Juncional , Proteínas de Membrana/química , Proteínas de Membrana/fisiologia , Modelos Biológicos , Núcleosídeo-Fosfato Quinase/fisiologia , Ocludina , Fosfoproteínas/fisiologia , Conformação Proteica , Junções Íntimas/ultraestrutura , Proteínas da Zônula de Oclusão , Proteína da Zônula de Oclusão-1 , Proteína da Zônula de Oclusão-2
19.
Parasitology ; 138(8): 1053-60, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21676279

RESUMO

Strongyloides ratti (Nagoya strain) is unique in that a portion of adults parasitizing the small intestine withstands 'worm expulsion', which starts at around day 8 post-infection (p.i.) by host immunity, and establishes in the large intestine after day 19 p.i. To investigate the mechanism, adults obtained from the small intestine at day 7 or 19 p.i. were transplanted into the colon of infection-primed immune rats. Adults obtained at day 7 p.i. were rejected quickly, whereas those obtained at day 19 p.i. could establish infection. Moreover, the body length and the number of intrauterine eggs increased in the large intestine. In a separate experiment, large intestinal parasitism was abolished by the treatment of host rats with an anti-oxidant, butylated hydroxyanisole. These results indicate that small intestinal adults between days 7 and 19 p.i. acquired the ability to parasitize the large intestine of immune rats, and that free radicals produced by the host may have played a significant role in the process.


Assuntos
Antioxidantes/farmacologia , Hidroxianisol Butilado/farmacologia , Colo/parasitologia , Intestino Delgado/parasitologia , Strongyloides ratti/patogenicidade , Estrongiloidíase/parasitologia , Animais , Tamanho Corporal , Fezes/parasitologia , Interações Hospedeiro-Parasita , Masculino , Contagem de Ovos de Parasitas , Ratos , Ratos Wistar , Strongyloides ratti/efeitos dos fármacos , Fatores de Tempo
20.
J Dent Res ; 100(6): 623-630, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33402027

RESUMO

It is difficult to correlate the direction of mandibular canal branches (MCBs) with altered sensation in dental treatments. In contrast, calcitonin gene-related peptide (CGRP) is related to vasodilation, bone formation, and the interaction with the peripheral nervous system. Therefore, we investigated the detailed morphological characteristics of MCBs using cone-beam computed tomography (CBCT) and observation of the CGRP distribution around the MCB. The MCB measurements were evaluated using principal component analysis (PCA) to identify morphological correlations. A total of 168 sides of mandibles from 84 cadavers were analyzed in this study. Most of the MCBs were primarily in the direction of the clock model from X to XI in sagittal sections and XII to I in coronal sections of the mandible. The structure of the MCB was divided into the fine canal branch (60.4%, 223/369), partial branch (24.4%, 90/369), and no canal branch (15.2%, 56/369). PCA indicated that the measurement element with the MCB and its structures were correlated in contrast to tooth factors. Positive CGRP reactions were clearly observed in the no-canal branch group compared to other groups. These data provide useful suggestions for MCB dynamics and information for clinical dental treatment.


Assuntos
Mandíbula , Nociceptividade , Dente , Cadáver , Calcitonina , Tomografia Computadorizada de Feixe Cônico , Humanos , Mandíbula/diagnóstico por imagem
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