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1.
Rev Sci Instrum ; 94(8)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38065167

RESUMO

This study developed a high-temperature and high-pressure (HTHP) cell for in situ neutron imaging of hydrothermal reactions. The cell's maximum temperature and pressure were 500 °C and 50 MPa, respectively, and its vessel for observing reactions comprised SUS316 stainless steel. Neutron transmission images were obtained to observe the behavior of sub- and supercritical water and the decomposition of two plastics (polypropylene and polyethylene) at HTHP. The images showed that water's density and phase changed with temperature and pressure, affecting neutron transmission (and thus image brightness). The plastics began to melt and change shape at 150-200 °C, and they decomposed at 500 °C and 20 MPa. This study provides a basis for future research using the HTHP cell to examine various reactions such as the decomposition of biomass samples, the reforming of heavy oil, and the synthesis of nano-materials using sub- and supercritical water.

2.
Int J Emerg Med ; 13(1): 59, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33256596

RESUMO

BACKGROUND: Air in the venous system may cause vascular air embolism, which is a potentially life-threatening event. The presence of air in venous system after basilar skull fracture is very rare. CASE PRESENTATION: A 77-year-old man fell from a truck bed and suffered head and neck trauma. On hospital arrival, his consciousness was clear and his vital signs were stable. His chief complaint was pain in the back of his head and neck. Head CT showed traumatic subarachnoid hemorrhage in the right frontal area and basilar skull fracture of the occipital bone. Whole body CT showed pneumocephalus and air in the jugular vein and right ventricle. The patient was placed in the supine position in a state of absolute rest to prevent vascular air embolism and was treated conservatively. On hospital day 3, CT was reperformed, revealing disappearance of air in the right ventricle and decreased air in the veins of the head and neck. On hospital day 4, the air in the veins disappeared completely on CT. He did not experience vascular air embolism after increasing of his activity level (e.g., raising his head on hospital day 3 and standing and walking alone on day 5). He was discharged 34 days after admission without sequelae. CONCLUSIONS: Head trauma patients with basilar skull fracture might develop vascular air embolism if physicians fail to detect air in the venous system on hospital arrival. A high degree of suspicion regarding air in venous system or heart is required when patients present with such injuries.

3.
FEBS Lett ; 594(14): 2254-2265, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32337711

RESUMO

TDP-43 is the major pathogenic protein of amyotrophic lateral sclerosis (ALS). Previously, we identified that TDP-43 interacts with G-quadruplex (G4)-containing RNA and is involved in their long-distance transport in neurons. For the molecular dissection of the TDP-43 and G4-RNA interaction, we analyzed it here in vitro and in cultured cells using a set of 10 mutant TDP-43 proteins from familial and sporadic ALS patients as well as using the TDP-43 C-terminal Gly-rich domain alone. Our results altogether indicate the involvement of the Gly-rich region of TDP-43 in the initial recognition and binding of G4-RNA, which then induces tight binding of TDP-43 with target RNAs, supposedly in conjunction with its RNA recognition motifs.


Assuntos
Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Quadruplex G , Glicina/metabolismo , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/isolamento & purificação , Células HEK293 , Humanos , Mutação , Domínios Proteicos , Transporte de RNA , RNA Mensageiro/genética
4.
Gan To Kagaku Ryoho ; 45(3): 501-503, 2018 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-29650918

RESUMO

Hepatocellular carcinoma(HCC)is not commonly observed with bile duct thrombosis.Here, we report a case of HCC with bile thrombi that extended to the liver hilum.The patient was a 61-year-old man who visited us due to untreated type B hepatitis.He underwent screening with a CT scan that revealed LDA on the right posterior lobe of his liver with infiltration of the bile duct.Generally, bile resection and reconstruction should be considered for curative resection for bile thrombi; however, we attempted to conserve the common bile duct to preserve the options of percutaneous therapy in case of tumor recurrence.We performed right lobectomy of the liver.The bile duct thrombus was extracted without bile duct resection or reconstruction.The patient is alive 6 months after the surgery without any development.


Assuntos
Ductos Biliares/irrigação sanguínea , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Trombose/cirurgia , Ductos Biliares/cirurgia , Carcinoma Hepatocelular/etiologia , Hepatite B/complicações , Humanos , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
5.
Gan To Kagaku Ryoho ; 45(3): 513-514, 2018 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-29650922

RESUMO

Creation of a cholecystojejunostomy has been recommended as one option in the palliation of biliary obstruction due to pancreatic carcinoma.However, it was a technique used for biliary drainage for acute cholecystitis a long time ago.We describe a patient who underwent a cholecystojejunostomy for acute cholecystitis 50 years prior to presentation, and then revealed a gallbladder carcinoma.


Assuntos
Colestase/cirurgia , Neoplasias da Vesícula Biliar/cirurgia , Idoso , Colecistectomia , Feminino , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Humanos , Jejunostomia , Fatores de Tempo , Resultado do Tratamento
6.
Gan To Kagaku Ryoho ; 44(12): 2026-2028, 2017 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-29394856

RESUMO

A 70's woman with a history of abdominal surgery for gastric cancer visited our hospital for the evaluation of bleeding during defecation.We diagnosed her with advanced rectal cancer and performed laparoscopic low anterior resection.As postoperative pathological staging was pT3N2M0, pStage III b, we included CapeOx therapy as adjuvant chemotherapy.One year and 4 months after the surgery, lung and liver metastases were revealed by CT and PET-CT scans.At the same time, dilatation of the main pancreatic duct(intraductal papillary mucinous neoplasm: IPMN)was detected.Thus, we first performed liver resection and then lung resection.After the surgery, new lung nodules and a mass lesion with IPMN with superior mesenteric venous invasion was found on CT scans.We then administered chemo-radiation therapy(CRT).After CRT, the lung and pancreatic lesions seemed to decrease slightly.Accidentally, a nodule on the cystic bladder was found, resected by transurethral resection of the bladder tumor(TUR-Bt), and diagnosed as a bladder cancer.Thirty months after the rectal surgery, she is continuing the S-1 chemotherapy with stable disease.


Assuntos
Adenocarcinoma Mucinoso/terapia , Carcinoma Papilar/terapia , Neoplasias Primárias Múltiplas/terapia , Neoplasias Pancreáticas/terapia , Idoso , Antineoplásicos/uso terapêutico , Feminino , Humanos , Estadiamento de Neoplasias , Neoplasias Pancreáticas/patologia
7.
PLoS One ; 10(6): e0131401, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26114770

RESUMO

We demonstrate a new analytical X-ray computed tomography technique for visualizing and quantifying the mass density of materials comprised of low atomic number elements with unknown atomic ratios. The mass density was obtained from the experimentally observed ratio of the imaginary and real parts of the complex X-ray refractive index. An empirical linear relationship between the X-ray mass attenuation coefficient of the materials and X-ray energy was found for X-ray energies between 8 keV and 30 keV. The mass density image of two polymer fibers was quantified using the proposed technique using a scanning-type X-ray microbeam computed tomography system equipped with a wedge absorber. The reconstructed mass density agrees well with the calculated one.


Assuntos
Modelos Teóricos , Tomografia Computadorizada por Raios X/métodos
8.
J Am Chem Soc ; 132(27): 9414-9, 2010 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-20560585

RESUMO

Tetrahedral amorphous carbon (ta-C) films with nanoscale structural anisotropy, which are obliquely deposited on a substrate by a filtered cathodic vacuum arc deposition (FAD) technique, allow anisotropic growth of mesostructured silica films thereon. The ta-C films have a uniformly tilted nanoscale columnar structure, which is caused by the self-shadowing effect during the oblique deposition, and consequently, the surface of the film can be morphologically anisotropic when the deposition angle is large enough. When silica films with a two-dimensional hexagonal mesostructure are grown under hydrothermal conditions on these ta-C films, the cylindrical mesochannels are aligned perpendicularly to the deposition direction of ta-C. The distribution of the in-plane alignment direction of the mesochannels can be controlled by the deposition angle of ta-C; it becomes narrower with the increase of the deposition angle and the consequent increase of the surface roughness. The observed alignment of the mesochannels is caused by the anisotropic accommodation of the surfactant molecules on the structurally anisotropic surface of the ta-C films, which is consistent with the fact that the ta-C films prepared at small deposition angles with smoother surface morphology have little alignment controllability. The ta-C film can be removed with the surfactant by calcination, allowing the formation of an aligned mesoporous silica film directly on a substrate. In contrast to this, obliquely evaporated SiO(2) films with a distinct tilted columnar structure and an anisotropic surface morphology provide neither continuous film formation nor controlled alignment of mesochannels even after providing hydrophobicity by a silylation process. This suggests the specificity, in particular, intrinsic strong hydrophobicity, of the ta-C films for the aligned mesostructured silica film formation.

9.
Rev Sci Instrum ; 80(3): 033707, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19334927

RESUMO

Two-directional differential phase contrast images were measured using an x-ray microbeam and a double wedge absorber. The wedge absorber converts the displacement of an x-ray beam that is refracted by an object into change of x-ray intensity. The double wedge absorber made it possible to detect values of two-directional refraction angle with microrad sensitivity simultaneously. By Fourier integration of two-directional phase gradients calculated from the refraction angle instead of line integration of one-directional phase gradients, we obtained a quantitative phase map without artifacts even when only a part of the boundaries of the object were in the field of view. One of the characteristics of this technique is flexibility in a sensitivity of the phase gradient. By changing of shape or material of the wedge absorber, it is comparatively easy to control the detection limit of the refraction angle.


Assuntos
Intensificação de Imagem Radiográfica/instrumentação , Radiografia/instrumentação , Refratometria/instrumentação , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
J Synchrotron Radiat ; 15(Pt 4): 329-34, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18552423

RESUMO

In situ visualization of the distribution and behaviour of water in a polymer electrolyte fuel cell during power generation has been demonstrated using a synchrotron X-ray imaging technique. Images were recorded using a CCD detector combined with a scintillator (Gd(2)O(2)S:Tb) and relay lens system, which were placed at 2.0 m or 2.5 m from the fuel cell. The images were measured continuously before and during power generation, and data on cell performance was recorded. The change of water distribution during power generation was obtained from X-ray images normalized with the initial state of the fuel cell. Compared with other techniques for visualizing the water in fuel cells, this technique enables the water distribution and behaviour in the fuel cell to be visualized during power generation with high spatial resolution. In particular, the effects of the specifications of the gas diffusion layer on the cathode side of the fuel cell on the distribution of water were efficiently identified. This is a very powerful technique for investigating the mechanism of water flow within the fuel cell and the relationship between water behaviour and cell performance.

11.
J Synchrotron Radiat ; 13(Pt 6): 484-8, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17057327

RESUMO

Visualization of the three-dimensional distribution of the crystal defects of large single crystals of calcium fluoride has been demonstrated by white X-ray section topography using sheet-like X-rays (BL28B2 at SPring-8). An image of the three-dimensional distribution of the crystal defects was reconstructed by stacking section topographs, which expressed the images of cross sections of the sample. The section topographs were recorded using a CMOS flat-panel imager or a CCD detector combined with scintillator (Gd(2)O(2)S:Tb) and relay lens system. The section topographs were measured by repeating cycles of exposure and sample translation along the direction perpendicular to the top face of the sample. Using high-brilliance and high-energy white X-rays ( approximately 60 keV) efficiently, visualization of the three-dimensional structure of subgrains of a sample of up to 60 mm in diameter was achieved. Furthermore, the three-dimensional distribution of the glide plane in the crystal was visualized by reconstructing the linear contrast of the glide plane.


Assuntos
Fluoreto de Cálcio/química , Cristalografia por Raios X/métodos , Interpretação de Imagem Assistida por Computador/métodos , Tomografia Óptica/métodos , Imageamento Tridimensional , Conformação Molecular
12.
Reproduction ; 128(5): 583-94, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15509704

RESUMO

Usp9x, an X-linked deubiquitylating enzyme, is stage dependently expressed in the supporting cells (i.e. Sertoli cells and granulosa cells) and germ cells during mouse gametogenesis. Af-6, a cell junction protein, has been identified as a substrate of Usp9x, suggesting a possible association between Usp9x and Af-6 in spermatogenesis and oogenesis. In this study, we examined the expression pattern of Af-6 and Usp9x and their intracellular localization in testes and ovaries of mice treated with or without pregnant mare serum gonadotropin (PMSG), an FSH-like hormone. In both testes and ovaries, Af-6 expression was predominantly observed in supporting cells, as well as in steroidogenic cells, but not in any germ cells. In Sertoli cells, Af-6 was continuously expressed throughout postnatal and adult stages, where both Af-6 and Usp9x were enriched at the sites of Sertoli-Sertoli and Sertoli-spermatid junctions especially at stages XI-VI. In the granulosa cells, Af-6, as well as Usp9x, was highly expressed in primordial and primary follicles, but its expression rapidly decreased after the late-secondary follicle stage. Interestingly, in PMSG-treated mice, the expression levels of Af-6 and Usp9x were synchronously enhanced, slightly in Sertoli cells and strongly in granulosa cells of the late-secondary and Graafian follicles. Such closely correlated expression patterns between Af-6 and Usp9x clearly suggest that Af-6 may be deubiquitylated by Usp9x in both Sertoli and granulosa cells. It further suggests that the post-translational regulation of Af-6 by Usp9x may be one potential pathway to control the cell adhesion dynamics in mammalian gametogenesis.


Assuntos
Endopeptidases/metabolismo , Células da Granulosa/metabolismo , Cinesinas/metabolismo , Miosinas/metabolismo , Células de Sertoli/metabolismo , Animais , Feminino , Gonadotropinas Equinas/farmacologia , Immunoblotting/métodos , Imuno-Histoquímica/métodos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Microscopia Confocal , Estimulação Química , Ubiquitina Tiolesterase
13.
Nat Mater ; 3(9): 651-6, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15311273

RESUMO

Films of mesoporous materials attract broad interest because of their wide applicability in the fields of optics and electronics. Although many of these films have a regular local porous structure, the structural regularity has not been used practically yet because of difficulties in its control on macroscopic scales. Here, we demonstrate the preparation of mesoporous silica films whose porous structure can be described as a single crystal, that is, a long-range order of cage-like pores is maintained over centimetre scales. These films have a three-dimensional hexagonal (space group P6(3)/mmc) porous structure, and the in-plane arrangement of the pores is strictly controlled by a polymeric substrate surface that has been treated by rubbing. This new class of single-crystalline films with mesoscopic periodic structure is a significant breakthrough in bottom-up nanotechnology, and could lead to novel devices, for example, optics in a soft X-ray region, and quantum electronics.


Assuntos
Cristalização/métodos , Membranas Artificiais , Nanotecnologia/métodos , Dióxido de Silício/química , Tensoativos/química , Substâncias Macromoleculares , Teste de Materiais , Porosidade , Propriedades de Superfície
14.
Atherosclerosis ; 162(1): 69-76, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11947899

RESUMO

The roles of transforming growth factor (TGF)-beta 1 in vascular proliferation, atherosclerosis, and plaque still remain controversial. TGF-beta 1 has been previously reported to inhibit the proliferation and migration of vascular smooth muscle cells and endothelial cells, in vitro. On the other hand, administration or transgenic overexpression of TGF-beta 1 enhances extracellular matrix synthesis and cellular hyperplasia of the intima and media in the normal artery and injured artery in vivo. We evaluated the correlation of arterial proliferation with plasma levels of TGF-beta 1 and TGF-beta receptor type II, respectively, in Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a new strain of spontaneous non-insulin-dependent diabetes mellitus (NIDDM) models. OLETF rats (n=30) were divided into three groups aged 5,15, and 30 weeks. Long-Evans Tokushima Otsuka (LETO) rats (n=30) were used as age-matched non-diabetic controls. Plasma TGF-beta1 and insulin were determined by enzyme-linked immunosorbent assay. Immunoreactive TGF-beta receptor type II antigen was detected by immunohistochemistry on the thoracic artery. Arterial media area was measured microscopically. Oral glucose tolerance test was performed to examine the stage of diabetes mellitus. The thoracic aorta wall section area increased significantly from the age of 15 weeks in OLETF rats, versus LETO rats. In both OLETF and LETO rats, plasma TGF-beta 1 increased significantly from the age of 15 weeks. In OLETF rats, plasma TGF-beta 1 increased significantly over that in LETO rats (P<0.001). Furthermore, TGF-beta receptor type II was detected on aortic wall as strong signals in OLETF rats, but only weakly in LETO rats. OLETF rats showed hyperinsulinemia and insulin resistance from the age of 15 weeks. With oral glucose tolerance test, from the age of 15 weeks, the high glucose level in OLETF rats was prolonged to 2 h after loading, and the insulin levels at both fasting and after loading were significantly higher than those of LETO rats (P<0.001). There are significant linear relations between plasma TGF-beta 1 antigen and aorta wall section area, and plasma TGF-beta 1 antigen and fasting insulin level (P<0.001, respectively). We found that plasma TGF-beta 1 and vascular TGF-beta type II receptors existed to a greater extent in pre- and early stages of diabetes mellitus (DM) in OLETF rats compared with LETO rats. The greater extent of each in OLETF rats was associated with hyperinsulinemia and/or vascular thickening.


Assuntos
Diabetes Mellitus/sangue , Endotélio Vascular/metabolismo , Músculo Liso Vascular/metabolismo , Fator de Crescimento Transformador beta/biossíntese , Envelhecimento/fisiologia , Animais , Aorta Torácica/metabolismo , Aorta Torácica/fisiopatologia , Pressão Sanguínea/fisiologia , Peso Corporal/fisiologia , Colesterol/sangue , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/fisiopatologia , Modelos Animais de Doenças , Teste de Tolerância a Glucose , Imuno-Histoquímica , Insulina/sangue , Masculino , Proteínas Serina-Treonina Quinases , Ratos , Ratos Endogâmicos OLETF , Ratos Long-Evans , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/biossíntese , Receptores de Fatores de Crescimento Transformadores beta/sangue , Fatores de Tempo , Fator de Crescimento Transformador beta/sangue , Fator de Crescimento Transformador beta1
15.
Gene Expr Patterns ; 2(1-2): 87-91, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12617843

RESUMO

During the Drosophila oogenic processes, Fat facets (Faf), an ubiquitin-specific protease essential for normal development of oocyte and eye, becomes localized at the posterior pole and is incorporated into the pole cells. This is dependent on Oskar, a key factor for pole cell determination, and suggests a role for Faf in germ cell differentiation and development. Here we show that Usp9x, an X-linked ortholog of Faf, is predominantly expressed in both germ cell and supporting cell lineages during mouse gonadal development in stage- and sex-dependent manners. Usp9x was first detected in PGCs at 10.5 days post coitum (dpc), and thereafter its expression both at mRNA and protein levels was enhanced in PGCs of both sexes at 11.5-13.5 dpc. In testis, Usp9x expression rapidly decreased to an undetectable level by 15.5 dpc and after birth to adult, no expression was found in any spermatogenic cells, except for weak expression in Sertoli cells. In the ovary, Usp9x expression in embryonic oocytes was also reduced at the newborn stage, its expression reappeared in oocytes at secondary follicle stage, and its products were highly accumulated in the cytoplasm of Graaffian follicles in adults. Although follicular epithelial cells also expressed Usp9x at a moderate level during postnatal development, its expression was downregulated from early secondary follicle stage. Thus, the present study is not only the first to demonstrate a conserved expression of fat facets in PGCs between mouse and fly, but also sex- and stage-dependent changes of a specific component of the deubiquitylation system during mammalian gonadal development.


Assuntos
Endopeptidases/genética , Camundongos/embriologia , Oogênese/fisiologia , Ovário/embriologia , Cromossomo X , Animais , Endopeptidases/metabolismo , Feminino , Imuno-Histoquímica , Oócitos/metabolismo , Ovário/metabolismo , Ubiquitina Tiolesterase
16.
Mech Dev ; 119 Suppl 1: S91-5, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14516667

RESUMO

During the Drosophila oogenic processes, Fat facets (Faf), an ubiquitin-specific protease essential for normal development of oocyte and eye, becomes localized at the posterior pole and is incorporated into the pole cells. This is dependent on Oskar, a key factor for pole cell determination, and suggests a role for Faf in germ cell differentiation and development. Here we show that Usp9x, an X-linked ortholog of Faf, is predominantly expressed in both germ cell and supporting cell lineages during mouse gonadal development in stage- and sex-dependent manners. Usp9x was first detected in PGCs at 10.5 days post coitum (dpc), and thereafter its expression both at mRNA and protein levels was enhanced in PGCs of both sexes at 11.5-13.5 dpc. In testis, Usp9x expression rapidly decreased to an undetectable level by 15.5 dpc and after birth to adult, no expression was found in any spermatogenic cells, except for weak expression in Sertoli cells. In the ovary, Usp9x expression in embryonic oocytes was also reduced at the newborn stage, its expression reappeared in oocytes at secondary follicle stage, and its products were highly accumulated in the cytoplasm of Graaffian follicles in adults. Although follicular epithelial cells also expressed Usp9x at a moderate level during postnatal development, its expression was downregulated from early secondary follicle stage. Thus, the present study is not only the first to demonstrate a conserved expression of fat facets in PGCs between mouse and fly, but also sex- and stage-dependent changes of a specific component of the deubiquitylation system during mammalian gonadal development.


Assuntos
Drosophila , Oogênese , Animais , Drosophila/genética , Gônadas , Humanos , Camundongos , Oócitos/metabolismo , Oogênese/genética , Ovário/metabolismo
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