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1.
J Dairy Sci ; 106(6): 4443-4453, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37080779

RESUMO

Kraft pulp (KP), an intermediate product obtained when wood chips are converted to paper, contains highly digestible fiber. This study evaluated the effect of KP inclusion in calf starters on growth performance, health, and plasma glucagon-like peptide 2 (GLP-2) concentration in calves. Twenty-five Holstein heifer calves were raised on a high plane of nutrition program using milk replacer containing 29% crude protein and 18% fat until 49 d after birth, and were fed calf starters containing KP at 0 (CON; n = 14) or 12% (KPS; n = 11) on a dry matter basis. All calves were fed the treatment calf starters and timothy hay ad libitum. Blood was collected at 4, 14, 21, 35, 49, 70, and 91 d after birth. Dry matter intake (DMI) of milk replacer and hay was not affected by treatment, whereas calf starter DMI was lower for KPS (0.93 kg/d) than for CON (1.03 kg/d). Higher neutral detergent fiber (NDF) content in KPS (31.7%) than in the CON starter (22.1%) resulted in higher NDF intake for KPS (0.55 kg/d) than for CON (0.47 kg/d). However, the consumption of starch was lower for KPS (0.29 kg/d) than for CON (0.33 kg/d). Despite the lower starter intake for KPS, body weight and average daily gain did not differ between treatments. No significant difference was observed in the plasma concentrations of metabolites, except for ß-hydroxybutyrate (BHB); BHB concentration was lower for KPS (216 µmol/L) than for CON (257 µmol/L). The area under the curve for plasma GLP-2 concentration was higher for KPS (54.1 ng/mL × d) than for CON (36.0 ng/mL × d). Additionally, the fecal score postweaning (1.19 and 1.48 for KPS and CON, respectively) and the number of days that calves developed diarrhea throughout the experimental period (2.50 d and 8.10 d for KPS and CON, respectively) were lower for KPS than for CON. These results indicate that feeding KP reduces the severity and frequency of diarrhea without adversely affecting growth performance. This could be attributed to the increased plasma GLP-2 concentration induced by higher NDF intake.


Assuntos
Dieta , Peptídeo 2 Semelhante ao Glucagon , Animais , Bovinos , Feminino , Desmame , Dieta/veterinária , Ração Animal/análise , Peso Corporal , Diarreia/veterinária , Ácido 3-Hidroxibutírico
2.
Insect Mol Biol ; 25(1): 16-23, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26471013

RESUMO

Ticks are obligate haematophagous arthropods that feed on vertebrate blood containing high levels of iron. The host-derived iron reacts to oxygen in the tick's body, and then high levels of reactive oxygen species, including hydrogen peroxide (H(2)O(2)), may be generated. High levels of H(2)O(2) cause oxidative stress to aerobic organisms. Therefore, antioxidant responses are necessary to control H(2)O(2). We focused on peroxiredoxins (Prxs), H(2)O(2) -scavenging enzymes. The sequence of Haemaphysalis longicornis 2-Cys Prx (HlPrx2) was identified from fat body cDNA libraries of this tick and recombinant HlPrx2 was then prepared using Escherichia coli. By comparison with the 2-Cys Prxs of other organisms, we found two conserved cysteines in HlPrx2, Cys51 and Cys172. We examined the antioxidant activity of HlPrx2 and mutant proteins produced by a single base substitution, converting one or both of these cysteines into serines. The assays revealed that proteins containing Cys51 showed antioxidant activity when H(2)O(2) was removed. Sodium dodecyl sulphate polyacrylamide gel electrophoresis and size-exclusion chromatography demonstrated that only the wild-type HlPrx2 formed homodimers and that all of the proteins that we made had a high molecular weight peak. These results indicate that both Cys51 and Cys172 are essential for the dimerization of HlPrx2, whereas only the Cys51 residue is necessary for antioxidant activity.


Assuntos
Ixodidae/enzimologia , Peroxirredoxinas/metabolismo , Sequência de Aminoácidos , Animais , Antioxidantes/metabolismo , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismo , Cromatografia em Gel , Dimerização , Peróxido de Hidrogênio , Ixodidae/genética , Dados de Sequência Molecular , Proteínas Recombinantes/metabolismo
3.
Eur J Gynaecol Oncol ; 35(4): 473-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25118497

RESUMO

Adenosarcoma of the uterine body is a rare mixed tumor in which a benign epithelial component is mixed with a malignant stromal element. It has been considered that this tumor originates from the endometrium and its most common finding of imaging is a polypoid tumor occupying the uterine cavity. The authors herein present a case of 37-year-old female with a complaint of abnormal vaginal bleeding. At the first visit, transvaginal ultrasound and magnetic resonance imaging (MRI) showed a round mass with a diameter of one cm in the uterine wall. No malignant pathological finding was detected. The patient visited the authors again one year later, because of continuous bleeding. At that time, they found a polypoid tumor in the uterine cavity, which turned out to be adenosarcoma with sarcomatous overgrowth. The round mass in the uterus detected at first time seems to have been incipience of adenosarcoma. Prodromal sign of adenosarcoma has not been reported previously.


Assuntos
Adenossarcoma/diagnóstico , Sintomas Prodrômicos , Neoplasias Uterinas/diagnóstico , Útero/patologia , Adenossarcoma/complicações , Adenossarcoma/cirurgia , Adulto , Feminino , Humanos , Histerectomia , Imageamento por Ressonância Magnética , Ultrassonografia , Hemorragia Uterina/etiologia , Neoplasias Uterinas/complicações , Neoplasias Uterinas/cirurgia , Útero/diagnóstico por imagem
4.
Opt Express ; 21(23): 28849-55, 2013 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-24514398

RESUMO

We report the design and use of a megawatt peak power Nd:YAG/Cr4+:YAG microchip laser for efficient second to ninth harmonic generation. We show that the sub-nanosecond pulse width region, between 100 ps and 1 ns, is ideally suited for efficient wavelength conversion. Using this feature, we report 85% second harmonic generation efficiency using lithium triborate (LBO), 60% fourth harmonic generation efficiency usingß-barium borate, and 44% IR to UV third harmonic generation efficiency using Type I and Type II LBO. Finally, we report the first demonstration of 118 nm VUV generation in xenon gas using a microchip laser.

5.
Parasitology ; 139(12): 1553-61, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22906745

RESUMO

Eimeria tenella is recognized worldwide as a significant pathogen in the poultry industry. However, a lack of methods for isolating developing schizonts has hindered the use of transcriptome analyses to discover novel and developmentally regulated genes. In the present study, we characterized the long-term successive development of E. tenella in infected chicken caeca and assessed the utility of laser microdissection (LMD) for the isolation of schizont RNA. Developmental stages, including those of the first, second, and third-generation schizonts and gametocytes, were synchronous. Using LMD, only the mature second-generation schizonts were successfully excised from the lamina propria, and non-degraded RNA was purified from the schizonts. E. tenella-specific genes were amplified by reverse transcription polymerase chain reaction (RT-PCR). These results augment our understanding of the E. tenella life cycle, and reveal LMD as a potentially useful tool for gene expression analyses of the intracellular stages of E. tenella.


Assuntos
Ceco/parasitologia , Eimeria tenella/fisiologia , Microdissecção , RNA de Protozoário/isolamento & purificação , Esquizontes/fisiologia , Animais , Galinhas , Eimeria tenella/genética , Estágios do Ciclo de Vida
6.
Nat Commun ; 11(1): 287, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31941881

RESUMO

Recent findings of new Higgs modes in unconventional superconductors require a classification and characterization of the modes allowed by nontrivial gap symmetry. Here we develop a theory for a tailored nonequilibrium quantum quench to excite all possible oscillation symmetries of a superconducting condensate. We show that both a finite momentum transfer and quench symmetry allow for an identification of the resulting Higgs oscillations. These serve as a fingerprint for the ground state gap symmetry. We provide a classification scheme of these oscillations and the quench symmetry based on group theory for the underlying lattice point group. For characterization, analytic calculations as well as full scale numeric simulations of the transient optical response resulting from an excitation by a realistic laser pulse are performed. Our classification of Higgs oscillations allows us to distinguish between different symmetries of the superconducting condensate.

7.
Sci Rep ; 9(1): 11505, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395929

RESUMO

A lamellar (L12 + B2) AlCoCrFeNi2.1 eutectic high entropy alloy (EHEA) was severely deformed by a novel hybrid-rolling process. During hybrid-rolling, the deformation was carried out in two stages, namely cryo-rolling followed by warm-rolling at 600 °C. The strain (ε) imparted in each of these steps was identical ~1.2, resulting in a total strain of ε~2.4 (corresponding to 90% reduction in thickness). The novel processing strategy resulted in an extremely heterogeneous microstructure consisting of retained lamellar and transformed nanocrystalline regions. Each of these regions consisted of different phases having different crystal structures and chemical compositions. The novel structure-composition dual heterogeneous microstructure originated from the stored energy of the cryo-rolling which accelerated transformations during subsequent low temperature warm-rolling. The dual heterogeneous microstructure yielded an unprecedented combination of strength (~2000 MPa) and ductility (~8%). The present study for the first time demonstrated that dual structure-composition heterogeneities can be a novel microstructural design strategy for achieving outstanding strength-ductility combination in multiphase high entropy alloys.

8.
Clin Exp Immunol ; 153(1): 127-35, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18460018

RESUMO

When oral tolerance was induced in either specific pathogen-free (SPF) or germ-free (GF) mice, ovalbumin (OVA) feeding before immunization induced oral tolerance successfully in SPF mice. On the other hand, OVA-specific immunoglobulin G1 (IgG1) and IgE titres in OVA-fed GF mice were comparable to those in phosphate-buffered saline-fed GF mice, thus demonstrating that oral tolerance could not be induced in GF mice. The frequencies of CD25(+) CD4(+)/CD4(+) cells in the mesenteric lymph node (MLN) and the absolute number of CD25(+) CD4(+) cells in the Peyer's patches and MLN of naive GF mice were significantly lower than those in naive SPF mice. In an in vitro assay, the CD25(+) CD4(+) cells from the naive SPF mice suppressed more effectively the proliferation of responder cells in a dose-dependent manner than those from the GF mice. In addition, the CD25(+) CD4(+) regulatory T (T(reg)) cells from the naive SPF mice produced higher amounts of interleukin (IL)-10 and transforming growth factor (TGF)-beta than those from the GF mice. When anti-TGF-beta neutralizing antibody, but not anti-IL-10 neutralizing antibody, was added to the in vitro proliferation assay, the suppressive effect of the CD25(+) CD4(+) T(reg) cells from the SPF mice was attenuated to the same level as that of the CD25(+) CD4(+) cells from the GF mice. In conclusion, the TGF-beta-producing CD25(+) CD4(+) T(reg) cells from the MLN of SPF mice played a major role in oral tolerance induction. In addition, as the regulatory function of the CD25(+) CD4(+) cells from the naive GF mice was much lower than that of the CD25(+) CD4(+) T(reg) cells from the SPF mice, indigenous microbiota are thus considered to contribute to the induction and maintenance of CD25(+) CD4(+) T(reg) cells.


Assuntos
Vida Livre de Germes , Intestinos/microbiologia , Linfonodos/imunologia , Organismos Livres de Patógenos Específicos , Linfócitos T Reguladores/imunologia , Animais , Proliferação de Células , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Fatores de Transcrição Forkhead/análise , Tolerância Imunológica , Interleucina-10/análise , Interleucina-2/análise , Intestinos/imunologia , Mesentério , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina , Baço/imunologia , Fator de Crescimento Transformador beta/análise
9.
Sci Rep ; 8(1): 3276, 2018 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-29459746

RESUMO

Nano-lamellar (L12 + B2) AlCoCrFeNi2.1 eutectic high entropy alloy (EHEA) was processed by cryo-rolling and annealing. The EHEA developed a novel hierarchical microstructure featured by fine lamellar regions consisting of FCC lamellae filled with ultrafine FCC grains (average size ~200-250 nm) and B2 lamellae, and coarse non-lamellar regions consisting of ultrafine FCC (average size ~200-250 nm), few coarse recrystallized FCC grains and rather coarse unrecrystallized B2 phase (~2.5 µm). This complex and hierarchical microstructure originated from differences in strain-partitioning amongst the constituent phases, affecting the driving force for recrystallization. The hierarchical microstructure of the cryo-rolled and annealed material resulted in simultaneous enhancement in strength (Yield Strength/YS: 1437 ± 26 MPa, Ultimate Tensile Strength/UTS: 1562 ± 33 MPa) and ductility (elongation to failure/ef ~ 14 ± 1%) as compared to the as-cast as well as cold-rolled and annealed materials. The present study for the first time demonstrated that cryo-deformation and annealing could be a novel microstructural design strategy for overcoming strength-ductility trade off in multiphase high entropy alloys.

10.
Clin Res Hepatol Gastroenterol ; 42(5): 462-469, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29753730

RESUMO

BACKGROUND: Myeloid-derived suppressor cells (MDSCs) exert their suppressive effects on multiple immune response and contribute to the development of many diseases. However, limited data is available on the involvement of MDSCs in human chronic HBV infection. OBJECTIVE: To investigate whether the progression of chronic HBV infection was associated with imbalance of MDSCs. METHODS: The percentages of MDSCs, regulatory T (Treg), Th1 and Tc1 cells in the peripheral blood from chronic hepatitis B (CHB) patients and healthy controls (HC) were determined by flow cytometry. Plasma levels of IL-10, TGF-ß and IFN-γ were measured using enzyme-linked immunosorbent assay. The potential association of the frequencies of MDSCs with clinical parameters was assessed. RESULTS: The percentages of MDSCs and Treg cells were significantly higher in CHB patients than those in HC. The percentages of MDSCs were negatively correlated with Th1 cells. Increased plasma IL-10 level and decreased IFN-γ level were found in CHB patients compared with HC. Moreover, the frequencies of MDSCs and plasma IL-10 levels were positively correlated with serum HBV DNA loads, as well as liver function impairment. CONCLUSION: The expanded peripheral MDSCs may contribute to poor viral clearance and disease progression during chronic HBV infection.


Assuntos
Hepatite B Crônica/sangue , Células Supressoras Mieloides/fisiologia , Adulto , Progressão da Doença , Feminino , Hepatite B Crônica/etiologia , Humanos , Masculino , Pessoa de Meia-Idade
11.
J Phys Condens Matter ; 29(42): 425805, 2017 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-28805192

RESUMO

Temperature dependent experimental Compton profiles of quaternary alloys Co1-x Cu x MnSb (x = 0.0, 0.2, 0.6 and 0.8) when decomposed into constituent profiles show that the sp-electron spin polarization is antiferromagnetically coupled to Mn-3d moments. The orbital magnetic moments derived from combination of magnetic Compton profiles (MCPs) and magnetization measurements are found to be small. Moreover, the first-principles full potential-linearized augmented plane wave (FP-LAPW) calculations have been performed to validate the experimental investigations of spin moments and half-Heusler properties. Present experimental and theoretical work show major role of Mn atoms in building-up the absolute spin moments. Our MCP data and spin-projected density of states derived from FP-LAPW computations show an increase in sp-d interaction in conduction region on increasing the Cu concentration. Further, Ruderman-Kittel-Kasuya-Yosida-type hybridization and antiferromagnetic superexchange interactions are witnessed in the reported alloys.

12.
World J Gastroenterol ; 12(36): 5793-7, 2006 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-17007044

RESUMO

AIM: To examine human beta-defensin-3 (hBD-3) expression in inflamed gastric mucosal tissues or MKN45 gastric cancer cells with or without H. pylori infection for better understanding the innate immune response to H. pylori. METHODS: We used reverse transcription-polymerase chain reactions and immunohistochemistry to examine hBD-3 expression in inflamed gastric mucosal tissues or MKN45 gastric cancer cells with or without H. pylori. Effects of hBD-3 against H. pylori were also evaluated. RESULTS: The mean mRNA expression of hBD-3 in H. pylori-positive specimens was significantly higher than that in H pylori-negative specimens (P = 0.0002, Mann-Whitney). In addition, unlike uninfected samples, 8 of 15 (53.33%) infected mucosal samples expressed hBD-3 protein. H. pylori dose-dependently induced mRNA expression of hBD-3 in MKN45 cells, an effect inhibited by adding anti-toll-like receptor (TLR)-4 antibody. HBD-3 protein completely inhibited H. pylori growth. CONCLUSION: Our results suggest that like hBD-2, hBD-3 may be involved in the pathophysiology of H. pylori-induced gastritis.


Assuntos
Mucosa Gástrica/metabolismo , Gastrite/metabolismo , Infecções por Helicobacter/metabolismo , beta-Defensinas/metabolismo , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Anti-Idiotípicos/farmacologia , Linhagem Celular Tumoral , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Gastrite/genética , Gastrite/microbiologia , Gastrite/fisiopatologia , Regulação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Infecções por Helicobacter/genética , Infecções por Helicobacter/fisiopatologia , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/patogenicidade , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Receptor 4 Toll-Like/imunologia , beta-Defensinas/genética , beta-Defensinas/farmacologia
13.
Cancer Res ; 52(19): 5278-81, 1992 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-1327505

RESUMO

Based on the findings that expression of endogenous tumor necrosis factor (enTNF), which is not present in TNF-susceptible cells, was generally observed in TNF-resistant cells and that TNF gene transfection gives rise to TNF resistance, the assumption was made that enTNF may be a protective protein against the cytotoxicity of exogenous TNF. However, it remains unknown whether the protection by enTNF is exerted in an intracellular or extracellular (autocrine) manner. We therefore transfected a nonsecretory human TNF gene (pTNF delta pro) into highly TNF-sensitive mouse tumorigenic fibroblasts (L-M cells) and investigated their TNF susceptibility. The transfectants expressed enTNF which was not secreted into the medium and acquired an appreciable degree of resistance to exogenous TNF. A significant increase in the manganous superoxide dismutase level was also noted in the transfectants. These findings suggest that enTNF exerts its protective function intracellularly by inducing manganous superoxide dismutase production.


Assuntos
Fator de Necrose Tumoral alfa/fisiologia , Animais , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Células Cultivadas , Resistência a Medicamentos , Fibroblastos/citologia , Fibroblastos/fisiologia , Humanos , Líquido Intracelular/enzimologia , Líquido Intracelular/fisiologia , Cinética , Camundongos , Receptores de Superfície Celular/metabolismo , Receptores do Fator de Necrose Tumoral , Proteínas Recombinantes/toxicidade , Sensibilidade e Especificidade , Superóxido Dismutase/metabolismo , Transfecção , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/toxicidade
14.
Cancer Res ; 52(22): 6258-62, 1992 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-1423271

RESUMO

One of the mechanisms of cytotoxicity by tumor necrosis factor (TNF) is the induction of reactive oxygen molecules. Cells producing endogenous tumor necrosis factor (enTNF) show resistance to the cytotoxicity of exogenous TNF by scavenging the reactive oxygen molecules. The intracellular hydroxyl radical production is also known to be involved in the heat-induced cytotoxicity. In the present study, we therefore examined the possibility that enTNF may act as a protective protein against the heat-induced cytotoxicity in a manner similar to that of exogenous TNF. Heat-sensitive L-M (mouse tumorigenic fibroblast) cells, originally expressing no enTNF, were transfected with a human TNF expression vector to produce enTNF. The stable transfectants showed apparent resistance to heat treatment. Conversely, when HeLa (human uterine cervical cancer) cells, originally producing an appreciable amount of enTNF, were transfected with an antisense TNF mRNA expression vector to inhibit enTNF synthesis, their heat sensitivity was enhanced. Furthermore, L-M cells which were transfected with nonsecretory human TNF expression vector also acquired resistance to heat treatment. In these cells, heat resistance correlated well with expression of enTNF and intracellular levels of manganous superoxide dismutase. These results indicate that enTNF exerts its intracellular protective effect against the heat-induced cytotoxicity by scavenging reactive oxygen with induced manganous superoxide dismutase in a manner similar to that found in cells treated with exogenous TNF.


Assuntos
Hipertermia Induzida , Fator de Necrose Tumoral alfa/fisiologia , Animais , Células Cultivadas , Fibroblastos/citologia , Vetores Genéticos/genética , Células HeLa , Temperatura Alta , Humanos , Camundongos , RNA Antissenso/genética , RNA Mensageiro/genética , Sensibilidade e Especificidade , Superóxido Dismutase/metabolismo , Transfecção , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/farmacologia
15.
Environ Entomol ; 45(1): 46-52, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26496951

RESUMO

The effect of competition on species that coexist with similar ecological niches is an important theme in ecology. Furthermore, species displacement by introduced or invaded species is also an important environmental problem for biological control and conservation ecology. We tested whether two species of phytoseiids could coexist in closed cages with ample quantities of the extraguild prey species Carpoglyphus lactis (L.). Three species of phytoseiid mites-Amblyseius eharai Amitai & Swirski (a species native to China), Amblyseius swirskii (Athias-Henriot) and Neoseiulus cucumeris (Oudemans) (both species were introduced from outside of China)-were tested under experimental conditions (25 ± 1°C, 90 ± 5% relative humidity, and a photoperiod of 14:10 [L:D] h). With extraguild prey, we found that the numbers of a single population of each phytoseiid species (initial density of 10 females per cage) reached a plateau between 18 and 25 d after introduction into the experimental cages, suggesting that density-dependent factors were operating. In closed environments, one of these density-dependent factors might be cannibalism by these species. With regression analyses, Lotka-Volterra equations estimated the rate of population increase (r) and the carrying capacity (K) of each species with the data from observations on population dynamics. We next observed the interactions of two phytoseiid species with abundant extraguild prey. In all species combinations, one species went extinct and the other increased in population size, despite the availability of sufficient extraguild prey, suggesting some type of competition must have caused the extinctions. We suggested that intraguild predation is the most plausible hypothesis to explain the results.


Assuntos
Ácaros/fisiologia , Animais , Biodiversidade , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Ácaros/crescimento & desenvolvimento , Dinâmica Populacional , Crescimento Demográfico , Comportamento Predatório , Especificidade da Espécie
16.
Rev Sci Instrum ; 87(5): 053905, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27250440

RESUMO

We measured the electrical conductivity σ of aluminum specimen consisting of submicron-grains by observing the AC magnetic susceptibility resulting from the eddy current. By using a commercial platform for magnetic measurement, contactless measurement of the relative electrical conductivity σn of a nonmagnetic metal is possible over a wide temperature (T) range. By referring to σ at room temperature, obtained by the four-terminal method, σn(T) was transformed into σ(T). This approach is useful for cylinder specimens, in which the estimation of the radius and/or volume is difficult. An experiment in which aluminum underwent accumulative roll bonding, which is a severe plastic deformation process, validated this method of evaluating σ as a function of the fraction of high-angle grain boundaries.

17.
J Phys Condens Matter ; 28(43): 436001, 2016 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-27602698

RESUMO

Spin selective magnetic hysteresis (SSMH) curves, orbital selective magnetic hysteresis (OSMH) curves and magnetic quantum number selective SSMH curves are obtained for CoFeB/MgO multilayer films by combining magnetic Compton profile measurements and superconducting quantum interference device (SQUID) magnetometer measurements. Although the SQUID magnetometer measurements do not show perpendicular magnetic anisotropy (PMA) in the CoFeB/MgO multilayer film, PMA behavior is observed in the OSMH and SSMH curves for the |m| = 2 magnetic quantum number states. These facts indicate that magnetization switching behavior is dominated by the orbital magnetization of the |m| = 2 magnetic quantum number states.

18.
Sci Rep ; 5: 16707, 2015 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-26582568

RESUMO

It is commonly accepted that twinning can induce an increase of strain-hardening rate during the tensile process of face-centered cubic (FCC) metals and alloys with low stacking fault energy (SFE). In this study, we explored the grain size effect on the strain-hardening behavior of a Cu-15 at.%Al alloy with low SFE. Instead of twinning, we detected a significant contribution of stacking faults (SFs) irrespective of the grain size even in the initial stage of tensile process. In contrast, twinning was more sensitive to the grain size, and the onset of deformation twins might be postponed to a higher strain with increasing the grain size. In the Cu-15 at.%Al alloy with a mean grain size of 47 µm, there was a stage where the strain-hardening rate increases with strain, and this was mainly induced by the SFs instead of twinning. Thus in parallel with the TWIP effect, we proposed that SFs also contribute significantly to the plasticity of FCC alloys with low SFE.

19.
J Invest Dermatol ; 117(3): 671-7, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11564175

RESUMO

We previously reported that wrinkle formation in the skin following long-term ultraviolet B irradiation is accompanied by decreases in skin elasticity and the curling of elastic fibers in the dermis. We further showed that wrinkles could be repaired by treatment with retinoic acid and that this was concomitant with the recovery of skin elasticity ascribed to the repair of damaged elastic fibers. Those studies suggested that decreasing the tortuosity of dermal elastic fibers is an important factor involved in inhibiting or repairing wrinkle formation. Therefore, it is of particular interest to determine whether the inhibition of elastase activity in vivo would prevent the damage of dermal elastic fibers and might abolish wrinkle formation associated with the loss of skin elasticity. Because the major elastase in the skin under noninflammatory conditions is skin fibroblast elastase, we used a specific inhibitor of that enzyme to assess its biologic role in wrinkle formation. The hind limb skins of Sprague-Dawley rats were irradiated with ultraviolet B at a suberythemal dose three times a week for 6 wk. During that period, 0.1-10.0 mM N-phenetylphosphonyl-leucyl-tryptophane, an inhibitor of skin fibroblast elastase, was applied topically five times a week. N-phenetylphosphonyl-leucyl-tryptophane application at concentrations of 0.1-1.0 mM abolished wrinkle formation in a concentration-dependent manner, with a peak for inhibition at 1.0 mM. This inhibition was accompanied by a continued low tortuosity of dermal elastic fibers and a maintenance of skin elasticity. Measurement of elastase activity after 6 wk of ultraviolet B irradiation demonstrated that whereas phosphoramidon-sensitive elastase activity was significantly enhanced in the ultraviolet B-exposed skin, there was no significant increase in that activity in the ultraviolet B-exposed, N-phenetylphosphonyl-leucyl-tryptophane-treated skin. These findings suggest that skin fibroblast elastase plays an essential part in the degeneration and/or tortuosity of elastic fibers induced by cumulative ultraviolet B irradiation.


Assuntos
Inibidores Enzimáticos/farmacologia , Elastase Pancreática/antagonistas & inibidores , Animais , Dipeptídeos/farmacologia , Relação Dose-Resposta a Droga , Fibroblastos/enzimologia , Fibroblastos/patologia , Fibroblastos/efeitos da radiação , Masculino , Ratos , Ratos Sprague-Dawley , Pele/enzimologia , Pele/patologia , Pele/efeitos da radiação , Raios Ultravioleta
20.
Endocrinology ; 136(2): 558-61, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7835288

RESUMO

The insulin receptor-related receptor (IRR) is a member of the insulin receptor family. In contrast to the widespread expression of insulin receptor and insulin-like growth factor-I receptor messenger RNA (mRNA), the expression of IRR mRNA is highly restricted to the kidney and stomach. IRR mRNA in the kidney is focally expressed in the renal distal tubule cells. However, the cellular localization of IRR mRNA in the stomach remains to be elucidated. Here, we examined the cellular localization of IRR mRNA in the rat stomach by in situ hybridization. IRR mRNA in the stomach was abundantly localized in the basal third of the oxyntic glands of the fundic stomach. IRR mRNA in the stomach was colocalized with mRNA for histidine decarboxylase, a marker for the enterochromaffin-like (ECL) cells, indicating that the expression was restricted to ECL cells. ECL cells actively produce and store histamine, which is an important physiological stimulant of acid secretion from the parietal cells. The preferential localization of IRR mRNA in ECL cells suggests that the IRR plays an important role in the function of these cells.


Assuntos
Células Enterocromafins/metabolismo , Mucosa Gástrica/metabolismo , Receptor de Insulina/biossíntese , Animais , Sequência de Bases , Histidina Descarboxilase/análise , Hibridização In Situ , Dados de Sequência Molecular , Sondas RNA , RNA Mensageiro/análise , Ratos
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