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2.
Phys Rev Lett ; 127(6): 069902, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34420355

RESUMO

This corrects the article DOI: 10.1103/PhysRevLett.116.217201.

6.
Pharmazie ; 73(1): 3-8, 2018 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-29441943

RESUMO

For the development of orally available liposomes, understanding the interaction of liposomes with the intestinal mucosa is important. An unstirred water layer (UWL) on the intestinal epithelium surface is a considerable permeability barrier for lipophilic drugs. Therefore, the effects of an UWL on liposome transport across intestinal epithelial cells must be elucidated. We evaluated the effects of the surface charge, particle size, and polyethylene glycol (PEG) modification of liposomes on their association with Caco-2 cells across an UWL. When the association of cationic liposomes with Caco-2 cells was evaluated under a reduction in UWL thickness by shaking, the uptake and/or amount of surface-bound cationic liposomes in cells was increased significantly in a shaking rate-dependent manner. The uptake and/or amount of surface-bound neutral liposomes were increased only at the highest shaking rate. No significant differences in the cellular association of anionic liposomes and PEG-modified liposomes were observed with or without shaking. The association of large liposomes with Caco-2 cells was affected considerably by an UWL compared with that of small liposomes. These results suggest that an UWL affects the surface binding and subsequent uptake of liposomes in Caco-2 cells according to their particle size, surface charge, and PEG modification.


Assuntos
Sistemas de Liberação de Medicamentos , Mucosa Intestinal/metabolismo , Polietilenoglicóis/química , Água/química , Administração Oral , Ânions , Transporte Biológico , Células CACO-2 , Cátions , Química Farmacêutica/métodos , Humanos , Lipossomos , Tamanho da Partícula , Permeabilidade
7.
Nat Commun ; 8(1): 1198, 2017 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-29084963

RESUMO

The behavior of the f-electrons in the lanthanides and actinides governs important macroscopic properties but their pressure and temperature dependence is not fully explored. Cerium with nominally just one 4f electron offers a case study with its iso-structural volume collapse from the γ-phase to the α-phase ending in a critical point (p C, V C, T C), unique among the elements, whose mechanism remains controversial. Here, we present longitudinal (c L) and transverse sound speeds (c T) versus pressure from higher than room temperature to T C for the first time. While c L experiences a non-linear dip at the volume collapse, c T shows a step-like change. This produces very peculiar macroscopic properties: the minimum in the bulk modulus becomes more pronounced, the step-like increase of the shear modulus diminishes and the Poisson's ratio becomes negative-meaning that cerium becomes auxetic. At the critical point itself cerium lacks any compressive strength but offers resistance to shear.

8.
J Fish Biol ; 90(6): 2363-2374, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28386984

RESUMO

This study identified ventilatory and behavioural responses in the marbled sole Pseudopleuronectes yokohamae under experimentally induced progressive decreases in dissolved oxygen (DO) levels. Ventilation frequency showed an increase with decreasing DO levels from normoxia to 2·75 mg O2 l-1 , followed by a decrease in ventilation frequency at decreased DO levels from 2·00 to 0·75 mg O2 l-1 . At DO levels below 2·00 mg l-1 , behaviours at the bottom were suppressed, whereas avoidance behaviours increased. A decrease in avoidance behaviours was observed from 1·00 to 0·75 mg O2 l-1 . Upside-down reversal and incapacitation at DO levels of 1·00-0·75 mg O2 l-1 suggested that sublethal effects on P. yokohamae were induced. The responses observed before the sublethal DO level could be interpreted as an effort to maintain oxygen uptake, reduce routine activities and facilitate avoidance. The observed DO level thresholds that induce behavioural responses, in addition to sublethal effects, indicate hypoxia-tolerance that is important for understanding the effects of hypoxia on coastal ecosystems.


Assuntos
Linguado/fisiologia , Oxigênio/análise , Animais , Comportamento Animal , Hipóxia/veterinária , Respiração , Água do Mar/química
9.
Aliment Pharmacol Ther ; 45(1): 169-177, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27862091

RESUMO

BACKGROUND: Abdominal ultrasound fails to detect over one-fourth of hepatocellular carcinoma (HCC) at an early stage in patients with cirrhosis. Identifying patients in whom ultrasound is of inadequate quality can inform interventions to improve surveillance effectiveness. AIM: To evaluate and identify predictors of ultrasound quality in patients with cirrhosis. METHODS: We performed a retrospective cohort study among patients who underwent ultrasound examination for a cirrhosis-related indication between April 2015 and October 2015. Three fellowship-trained abdominal radiologists collectively reviewed all ultrasound exams and categorised exam quality as definitely adequate, likely adequate, likely inadequate and definitely inadequate to exclude liver lesions. We performed multivariable logistic regression to determine characteristics associated with inadequate ultrasound quality. RESULTS: Among 941 patients, 191 (20.3%) ultrasounds were inadequate for excluding HCC- 134 definitely inadequate and 57 likely inadequate. In multivariable analysis, inadequate quality was associated with male gender (OR 1.68, 95% CI 1.14-2.48), body mass index category (OR 1.67, 95% CI 1.45-1.93), Child-Pugh B or C cirrhosis (OR 1.93, 95% CI 1.32-2.81), alcohol-related cirrhosis (OR 2.11, 95% CI 1.33-3.37), NASH cirrhosis (OR 2.87, 95% CI 1.71-4.80), and in-patient status (OR 1.55, 95% CI 1.01-2.37). Ultrasounds were inadequate in over one-third of patients with Child-Pugh C cirrhosis, BMI >35, or NASH cirrhosis. CONCLUSIONS: One in five ultrasounds in patients with cirrhosis are inadequate for exclusion of HCC, which can contribute to surveillance failure. Alternative surveillance modalities are needed in subgroups prone to inadequate ultrasounds including obese patients, those with Child Pugh B or C cirrhosis, and those with alcohol- or NASH-related cirrhosis.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Cirrose Hepática/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Vigilância da População , Ultrassonografia/normas , Adulto , Idoso , Carcinoma Hepatocelular/epidemiologia , Estudos de Coortes , Feminino , Humanos , Cirrose Hepática/epidemiologia , Neoplasias Hepáticas/epidemiologia , Masculino , Pessoa de Meia-Idade , Vigilância da População/métodos , Valor Preditivo dos Testes , Estudos Retrospectivos
10.
Phys Rev Lett ; 116(21): 217201, 2016 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-27284670

RESUMO

A hidden order that emerges in the frustrated pyrochlore Tb_{2+x}Ti_{2-x}O_{7+y} with T_{c}=0.53 K is studied using specific heat, magnetization, and neutron scattering experiments on a high-quality single crystal. Semiquantitative analyses based on a pseudospin-1/2 Hamiltonian for ionic non-Kramers magnetic doublets demonstrate that it is an ordered state of electric quadrupole moments. The elusive spin liquid state of the nominal Tb_{2}Ti_{2}O_{7} is most likely a U(1) quantum spin-liquid state.

13.
Neuroscience ; 320: 1-7, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-26851771

RESUMO

Glycinergic neurons provide an important mechanism to control excitation of motoneurons in the brainstem and a reduction or loss of glycinergic inhibition can be deleterious by leading to hyperexcitation such as in hyperekplexia or neurodegeneration and neuronal death as in amyotrophic lateral sclerosis (ALS). Second messenger systems that change cyclic AMP and lead to phosphorylation of the α3 subunit of the glycine receptor (GlyR α3) have been shown to be potent modulators of synaptic inhibition in the spinal cord and brain stem. In this study we analyzed the role of GlyR α3 in synaptic inhibition to the hypoglossal nucleus using Glra3 (the gene encoding the glycine receptor α3 subunit) knockout mice. We observed that baseline glycinergic synaptic transmission to nucleus of hypoglossal motoneurons is rather normal in Glra3 knockout mice. Interestingly, we found that the modulation of synaptic transmission by cAMP-mediated pathways appeared to be reduced in Glra3 knockout mice. In the second postnatal week the forskolin-induced increase of miniature inhibitory postsynaptic potential (mIPSC) frequency was significantly larger in control as compared to Glra3 knockout mice suggesting that presynaptic glycine release in the hypoglossal nucleus is partially depending on GlyR α3.


Assuntos
Tronco Encefálico/metabolismo , Potenciais Pós-Sinápticos Inibidores/fisiologia , Neurônios Motores/metabolismo , Receptores de Glicina/metabolismo , Transmissão Sináptica/fisiologia , Animais , Feminino , Glicina/metabolismo , Masculino , Camundongos , Camundongos Knockout , Inibição Neural/fisiologia , Técnicas de Cultura de Órgãos , Técnicas de Patch-Clamp , Receptores de Glicina/deficiência
14.
Pharmazie ; 71(11): 619-624, 2016 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29441964

RESUMO

Macrophages have been assumed to have a crucial role in the development of inflammatory bowel disease (IBD). However, involvement of intestinal macrophages in IBD onset and functional alterations of macrophages during IBD development has not been clarified. We investigated the effect of exposure of compounds used in the induction of colitis in mice on the immune responses of peritoneal macrophages in mice. 2,4,6- trinitrobenzenesulfonic acid and oxazolone did not affect the production of interleukin (IL)-10 and IL-12 from lipopolysaccharide (LPS)-stimulated peritoneal macrophages from BALB/c mice. A significant increase in IL-10 secretion and decrease in IL-12 production from LPS-stimulated macrophages were observed upon exposure to dextran sodium sulfate (DSS). TNF-α production was enhanced significantly by exposure to DSS and LPS. The level of nitric-oxide production from macrophages was increased slightly by exposure to DSS and LPS. Expression of sphingosine kinase-1 and LIGHT (both of which are specific biomarkers of M2b macrophages) was observed in macrophages upon DSS exposure. Alteration of cytokine production in macrophages was observed upon DSS exposure in the absence of LPS stimulation. Peritoneal macrophages from C57BL/6 mice showed similar responses to peritoneal macrophages from BALB/c mice against DSS. These results suggest that DSS directs the immune response of macrophages towards the M2b phenotype.


Assuntos
Citocinas/biossíntese , Sulfato de Dextrana/farmacologia , Macrófagos Peritoneais/metabolismo , Animais , Colite/induzido quimicamente , Colite/patologia , Feminino , Técnicas In Vitro , Interleucina-10/biossíntese , Interleucina-10/genética , Interleucina-12/biossíntese , Interleucina-12/genética , Lipopolissacarídeos/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Óxido Nítrico/biossíntese , Fosfotransferases (Aceptor do Grupo Álcool)/biossíntese , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Especificidade da Espécie , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral/biossíntese , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética
15.
Phys Rev Lett ; 114(3): 037202, 2015 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-25659018

RESUMO

High-precision dc magnetization measurements have been made on Cu(C4H4N2) (NO3)2 in magnetic fields up to 14.7 T, slightly above the saturation field Hs=13.97 T, in the temperature range from 0.08 to 15 K. The magnetization curve and differential susceptibility at the lowest temperature show excellent agreement with exact theoretical results for the spin-1/2 Heisenberg antiferromagnet in one dimension. A broad peak is observed in magnetization measured as a function of temperature, signaling a crossover to a low-temperature Tomonaga-Luttinger-liquid regime. With an increasing field, the peak moves gradually to lower temperatures, compressing the regime, and, at Hs, the magnetization exhibits a strong upturn. This quantum critical behavior of the magnetization and that of the specific heat withstand quantitative tests against theory, demonstrating that the material is a practically perfect one-dimensional spin-1/2 Heisenberg antiferromagnet.

16.
Sarcoidosis Vasc Diffuse Lung Dis ; 30(1): 43-51, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24003534

RESUMO

BACKGROUND: The serum Krebs von der Lungen-6 (KL-6) level is a useful marker correlated with the severity of various interstitial lung diseases. There have been few reports about the clinical characteristics of organizing pneumonia (OP) associated with the serum KL-6 levels. OBJECTIVE: This study was performed to determine whether the serum KL-6 levels can help determine the optimal treatment for OP. DESIGNS: Patients diagnosed with OP by clinical, radiological and histopathological findings were retrospectively reviewed. The OP patients were classified into two groups based on their serum KL-6 levels: normal KL-6 and high KL-6 groups. The two groups were compared with regard to their clinical and radiological data and therapeutic response one month after the start of treatment. RESULTS: The clinical records of twenty-two patients diagnosed with OP were reviewed. The serum KL-6 level was elevated in 11 of the 22 patients. There were no obvious differences in the clinical data between the two groups, although patients in the normal KL-6 group tended to have a fever. There were no significant differences in the chest X-ray (CXR) score or computed tomography (CT) score between the two groups. The CXR scores were correlated with the serum KL-6 levels. At 1 month after the diagnosis, 11 patients who needed treatment with prednisolone were included in the high KL-6 group. CONCLUSIONS: Patients with normal KL-6 levels showed lower CXR and CT scores. The serum KL-6 level on admission is a useful marker to judge the need for corticosteroid treatment in OP patients.


Assuntos
Biomarcadores/sangue , Pneumonia em Organização Criptogênica/sangue , Mucina-1/sangue , Corticosteroides/uso terapêutico , Broncoscopia , Pneumonia em Organização Criptogênica/diagnóstico , Pneumonia em Organização Criptogênica/diagnóstico por imagem , Pneumonia em Organização Criptogênica/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
17.
J Phys Condens Matter ; 25(34): 345401, 2013 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-23884010

RESUMO

The longitudinal and transverse sound speeds, cL and cT, of polycrystalline cerium were measured under pressure across the iso-structural γ-α phase transition at 0.75 GPa to beyond 3 GPa. In contrast to previous methods all quantities were directly obtained and no assumptions were made about the size of the volume collapse. Up to the transition our values for cL are in excellent agreement with previous ones, while our values for cT are significantly lower. We deduce values for the adiabatic bulk modulus BS, the shear modulus [Formula: see text], and the pressure dependent Debye temperature, ΘD(p). ΘD(p) is in good agreement with recent results derived from phonon dispersion measurements on single crystals. The ratio of the Debye temperature values bracketing the transition indicates a lattice contribution to the entropy change across the volume collapse, ΔSvib(γ â†’ α) ≈ (0.68 ± 0.06)kB, consistent with previous results obtained by neutron scattering, but significantly larger than other previously determined values.

18.
J Perinatol ; 33(7): 569-71, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23803677

RESUMO

We encountered a neonatal patient with hemophagocytic lymphohistiocytosis (HLH) whose mother was positive for anti-Ro/SSA and anti-La/SSB antibodies. Complete atrioventricular block was found in a male patient at 29 weeks of gestation. The patient was born at 40 weeks of gestation. He showed severe circulatory disturbance at 22 h after the birth, and he also had elevated serum levels of aspartate aminotransferase (1027 IU l(-1)), alanine aminotransferase (121 IU l(-1)), lactic dehydrogenase (3490 IU l(-1)), ferritin (9769.7 ng ml(-1)) and soluble interleukin-2 (IL-2) receptor (3230 U ml(-1)). We could not find any known HLH genetic abnormality in the patient, but he fulfilled seven of the eight criteria for HLH. Serum levels of IL-6 and IL-8 had been already elevated in his cord blood, and serum levels of granulocyte-macrophage colony-stimulating factor and IL-8 were significantly increased on the second day of life. His symptoms regressed with the administration of hydrocortisone. We presumed that transplacental transfer of maternal antibodies could be related to the occurrence of HLH.


Assuntos
Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfo-Histiocitose Hemofagocítica/imunologia , Síndrome de Sjogren/imunologia , Anticorpos Antinucleares/análise , Bloqueio Atrioventricular , Autoimunidade , Quimiocinas/imunologia , Citocinas/sangue , Humanos , Recém-Nascido , Interleucina-6/sangue , Interleucina-8/sangue , Masculino
19.
J Chem Phys ; 138(2): 024302, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23320678

RESUMO

Cascade Si LVV Auger decays following KL(23)L(23) Auger transitions have been measured in SiF(4) molecule using an electron spectrometer combined with monochromatized undulator radiation. Molecular cascade processes from the two 2p holes states largely generate wide band structures in the spectra due to sequential electron emission leading to multiple valence holes. However, a peak with high yield is observed for the first time at about 103 eV, an energy being considerably higher than the energies of the normal LVV Auger electron, in the instance of the resonant excitation of Si 1s electron into the vacant molecular orbital. This peak is presumed to originate from the participator decay from the state with two 2p holes and one excited electron into the state with one 2p hole and one valence hole. A similar peak with less intensity is detected in the photoexcitation of the 1s electron into a Rydberg orbital. After the normal KL(23)L(23) Auger transition, the resultant cascade spectrum shows several peaks, e.g., 61 eV, 76 eV, and 82 eV. The former two peaks are assigned to the Auger transitions of Si atoms produced through molecular ion dissociation after cascade decays, and the latter is probably ascribed to the second step Auger decay into states having a 2p hole together with two valence holes.

20.
Pharmazie ; 67(5): 400-5, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22764571

RESUMO

Gene therapy is a promising treatment option for cancers generated by mutation of oncogenes or tumor suppressor genes. The transcriptional process is activated by doxorubicin (DXR), and gene expression efficiency followed by gene transfection can be enhanced by the combination-use of DXR. Therefore, co-encapsulation of plasmid DNA (pDNA) and DXR into non-viral gene carriers can enhance gene expression. Here, we prepared DXR-loaded liposome/pDNA complexes (DXR-loaded PEGylated lipoplexes) by co-encapsulating pDNA and DXR into liposomes. Gene expression was enhanced by DXR encapsulation into lipoplexes in colon-26 cells and cultured mouse macrophages, and this gene expression level was significantly higher than that obtained by the combination of PEGylated lipoplexes and free DXR. Moreover, the activation profiles of transcriptional factors induced by DXR-loaded lipoplexes were different from those induced by free DXR; therefore, co-encapsulation of pDNA and DXR into gene carriers might be contributed to effective enhancement of gene expression. These findings provide a new approach for achieving effective gene transfection using PEGylated lipoplexes.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/farmacologia , DNA/administração & dosagem , DNA/genética , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacologia , Expressão Gênica/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Análise de Variância , Animais , Linhagem Celular , Corantes , DNA/biossíntese , Portadores de Fármacos , Feminino , Lipossomos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/genética , Tamanho da Partícula , Polietilenoglicóis , Reação em Cadeia da Polimerase em Tempo Real , Sais de Tetrazólio , Tiazóis , Fator de Transcrição AP-1/genética
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