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1.
Sci Technol Adv Mater ; 25(1): 2331959, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38572411

RESUMEN

Hydrogels are flexible materials that typically accommodate elongation with positive Poisson's ratios. Auxetic property, i.e., the negative Poisson's ratio, of elastic materials can be macroscopically implemented by the structural design of the continuum. We realize it without mold for hydrogel made of cellulose nanofibers (CNFs). The complex structural design of auxetic Kirigami is first implemented on the dry CNF film, i.e., so-called nanopaper, by laser processing, and the CNF hydrogel is formed by dipping the film in liquid water. The CNF films show anisotropic swelling where drastic volumetric change mainly originates from increase in the thickness. This anisotropy makes the design and fabrication of the emergent Kirigami hydrogel straightforward. We characterize the flexibility of this mechanical metamaterial made of hydrogel by cyclic tensile loading starting from the initial end-to-end distance of dry sample. The tensile load at the maximum strain decreases with the increasing number of cycles. Furthermore, the necessary work up to the maximum strain even decreases to the negative value, while the work of restoration to the original end-to-end distance increases from the negative value to the positive. The equilibrium strain where the force changes the sign increases to reach a plateau. This plastic deformation due to the cyclic loading can be regarded as the adaptive response without fracture to the applied dynamic loading input.


Highly anisotropic swelling-based gelation of dry film of cellulose nanofibers enables development of emergent hydrogel Kirigami with auxetic behavior. Furthermore, adaptive response to the iterative loading condition is found.

2.
J Vet Med Sci ; 86(6): 619-622, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38631871

RESUMEN

Cryptococcosis, a globally distributed mycotic disease caused by Cryptococcus neoformans or C. gattii, has been extensively studied in various domestic animals and humans. However, non-domestic species have often been overlooked in the literature, with limited attention given to their susceptibility and contribution to the epidemiology of the disease. In this study, a captive two-year-old Cape hyrax in a Japanese zoo exhibited neurological symptoms and torticollis, ultimately succumbing to the infection. Necropsy and pathological analyses, including histopathological techniques and PCR, revealed the presence of C. neoformans in the lungs, cerebrum, and internal auditory canal. While cryptococcosis has been reported in various wild animals globally, this case represents the first documented cryptococcosis in Cape hyrax.


Asunto(s)
Animales de Zoológico , Criptococosis , Cryptococcus neoformans , Animales , Criptococosis/veterinaria , Criptococosis/patología , Criptococosis/microbiología , Criptococosis/diagnóstico , Cryptococcus neoformans/aislamiento & purificación , Resultado Fatal , Masculino , Damanes , Pulmón/patología , Pulmón/microbiología , Cerebro/patología , Cerebro/microbiología
3.
Sci Rep ; 13(1): 18140, 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37875507

RESUMEN

We present a combined experimental and theoretical study of the Se-treated GaAs(001)-([Formula: see text]) surface. The ([Formula: see text]) structure with the two-fold coordinated Se atom at the outermost layer and the three-fold coordinated Se atom at the third layer was found to be energetically stable and agrees well with the experimental data from scanning tunneling microscopy, low energy electron diffraction, and x-ray photoelectron spectroscopy. This atomic geometry accounts for the improved stability of the Se-treated surface against the oxidation. The present result allows us to address a long-standing question on the structure of the Se-passivated GaAs surface, and will leads us to a more complete understanding of the physical origin of the electrical and chemical passivation of Se-treated GaAs surface.

4.
J Vet Med Sci ; 85(12): 1296-1300, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-37821381

RESUMEN

The brain of a rhesus monkey that died at 43 years of age with symptoms of suspected cognitive dysfunction was analyzed. pathological analyses revealed characteristic Alzheimer's disease-related lesions: the aggregation of amyloid ß (Aß) in the form of senile plaques and phosphorylated tau proteins. We also revealed that Aß43, which is prone to aggregation and toxicity in humans, is involved in senile plaques in the brain of the rhesus monkey, as well as several other Aß species. Comparative studies of neuropathology using aged nonhuman primates lack behavioral descriptions compared to human medicine. This case report showed behavioral abnormalities and the detailed pathological changes that may have caused it in a super-aged rhesus monkey.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Animales , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/veterinaria , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Macaca mulatta/metabolismo , Placa Amiloide/veterinaria , Placa Amiloide/metabolismo , Placa Amiloide/patología , Proteínas tau/metabolismo
5.
J Pathol ; 261(1): 96-104, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37550796

RESUMEN

Fibrinogen Aα-chain amyloidosis is a hereditary systemic amyloidosis characterized by glomerular amyloid depositions, which are derived from the fibrinogen Aα-chain variant in humans. Despite its unique pathology, the pathogenic mechanisms of this disease are only partially understood. This is in part because comparative pathological studies on fibrinogen Aα-chain amyloidosis are currently unavailable as there is a lack of reported cases in animals other than humans. In this study, mass spectrometry-based proteomic analyses of Japanese squirrels (Sciurus lis) that died in five Japanese zoos showed that they developed glomerular-associated fibrinogen Aα-chain amyloidosis with an extremely high incidence rate (29/38 cases, 76.3%). The condition was found to be age-dependent in the Japanese squirrels, with 89% of individuals over 4 years of age affected. Mass spectrometry revealed that the C-terminal region of the fibrinogen Aα-chain was involved in amyloidogenesis in Japanese squirrels as well as humans. No gene variations were identified between amyloid-positive and amyloid-negative squirrels, which contrasted with the available data for humans. The results indicate that fibrinogen Aα-chain amyloidosis is a senile amyloidosis in Japanese squirrels. The results have also provided comparative pathological support that the amyloidogenic C-terminal region of the fibrinogen Aα-chain is involved in the characteristic glomerular pathology, regardless of the animal species. This study elucidates the potential causes of death in Japanese squirrels and will contribute to future comparative pathological studies of fibrinogen Aα-chain amyloidosis. © 2023 The Pathological Society of Great Britain and Ireland.


Asunto(s)
Amiloidosis , Enfermedades Renales , Sciuridae , Animales , Amiloidosis/epidemiología , Amiloidosis/genética , Amiloidosis/veterinaria , Brotes de Enfermedades , Enfermedades Renales/genética , Enfermedades Renales/veterinaria , Proteómica
6.
Anticancer Res ; 43(2): 911-918, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36697097

RESUMEN

BACKGROUND/AIM: The chemotherapeutic landscape for hepatocellular carcinomas (HCCs) has changed dramatically with the availability of several treatment options. This study aimed to assess the long-term outcomes of lenvatinib treatment and analyze its feasibility in the sequential treatment of HCCs. PATIENTS AND METHODS: Eighty-five consecutive patients who received lenvatinib for unresectable HCCs were investigated retrospectively. Survival was assessed based on when the patients were first radiologically diagnosed with progressive disease. Among those with radiologically diagnosed stable or progressive disease at 3 months after lenvatinib administration, the cutoff α-fetoprotein (AFP) ratio (ratio of the AFP level after lenvatinib treatment to the pretreatment AFP level) that was predictive of survival was determined using receiver operating characteristic analysis. RESULTS: The median survival time (MST) was significantly worse among patients diagnosed with progressive disease at 1 month after treatment than among those diagnosed at 2-3 or 3-4 months after treatment [MSTs at 1, 2-3, and 3-4 months: 2.2, 10.2, and 17.3 months, respectively (p<0.001)]. An AFP ratio of 1.36 (computed using the AFP level at 3 months after lenvatinib treatment) was significantly predictive of survival in patients with stable or progressive disease (26.3 vs. 11.3 months, p=0.0024). CONCLUSION: The prognosis of patients on lenvatinib who develop early progressive disease is dismal. Thus, their treatment should be ceased or switched. The 3-month AFP ratio of 1.36 may be a potentially useful cutoff for considering a switch to other treatments in patients radiologically diagnosed with stable or progressive disease.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Quinolinas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/tratamiento farmacológico , alfa-Fetoproteínas , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/tratamiento farmacológico , Estudios Retrospectivos , Compuestos de Fenilurea/efectos adversos , Quinolinas/uso terapéutico
7.
Nanomaterials (Basel) ; 12(14)2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35889653

RESUMEN

Nanopapers fabricated from cellulose nanofibers (CNFs) are flexible for bending while they are rather stiff against stretching, which is a common feature shared by conventional paper-based materials in contrast with typical elastomers. Cellulose nanopapers have therefore been expected to be adopted in flexible device applications, but their lack of stretching flexibility can be a bottleneck for specific situations. The high stretching flexibility of nanopapers can effectively be realized by the implementation of Kirigami structures, but there has never been discussion on the mechanical resilience where stretching is not a single event. In this study, we experimentally revealed the mechanical resilience of nanopapers implemented with Kirigami structures for stretching flexibility by iterative tensile tests with large strains. Although the residual strains are found to increase with larger maximum strains and a larger number of stretching cycles, the high mechanical resilience was also confirmed, as expected for moderate maximum strains. Furthermore, we also showed that the round edges of cut patterns instead of bare sharp ones significantly improve the mechanical resilience for harsh stretching conditions. Thus, the design principle of relaxing the stress focusing is not only important in circumventing fractures but also in realizing mechanical resilience.

8.
J Orthop Case Rep ; 11(4): 14-17, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34327157

RESUMEN

INTRODUCTION: Hypophosphatemic osteomalacia can be overlooked or confused with other musculoskeletal disorders due to the variety of associated clinical, laboratory, and radiographic findings. If osteomalacia is diagnosed early and the fractures are not displaced, they often heal with nutritional supplements, but, if they progress to displaced fractures, they may require surgical intervention. CASE REPORT: We present a case of secondary osteomalacia due to autoimmune polyendocrine syndrome Type 2 due to this condition, the patient developed bilateral tibial proximal fractures and her varus deformity had progressed. No clear indication of the timing for surgery for adults with osteomalacia has been reported. However, medical treatment improves the symptoms of osteomalacia and it is reported that in children, appropriate level of the serum phosphate (P) should be attained and maintained for the successful bone healing after osteotomy. Therefore, we prioritized pharmacological treatment and prescribed surgery after confirming that the value of serum phosphate P had been improved to recommended levels (2.5-3.5 mg/dl). We performed high tibial osteotomy for the right side and gradual correction by an external fixation for the left tibia, because of more severe deformation, and converted to an internal fixation to shorten the treatment period. During conversion, we performed the operation with a locking plate by the minimal invasive plate osteosynthesis method (MIPO). CONCLUSION: We conclude that the use of different deformity correction methods, depending on the degree of deformity, and the pharmacological treatment of osteomalacia may lead to favorable results.

9.
Materials (Basel) ; 11(11)2018 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-30445738

RESUMEN

This research investigated high-temperature corrosion (500 °C) of Cr-Mo steel processed using water jet peening or multifunction cavitation (MFC), and the suitability of such steel for high-temperature boilers and reaction vessels. High-temperature corrosion was induced using an embedment test and a coating test using sulfide-type K2SO4-Na2SO4 powder. To measure the relaxation of the residual stress due to the decrease in work hardening caused by an increase in specimen temperature and the difference in thermal shrinkage between the surface and interior of the specimen, a thermal cycling test was conducted. For the MFC-processed specimen, the oxide film that formed on the surface suppressed mass loss, prevented crack formation, and reduced the compressive residual stress caused by high-temperature corrosion. MFC-processed Cr-Mo steel is thus suitable for a high-temperature corrosion environment.

10.
Rev Sci Instrum ; 87(4): 043104, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-27131651

RESUMEN

To perform the femtosecond pump-probe spectroscopy under high pressure and low temperature, we constructed a measurement system with a piston cylinder type pressure cell installing an optical fiber bundle. The applied pressure was achieved to 6 kbar and the cell was cooled down to 15 K. Several demonstrations revealed that broadening and change of polarization of pulse (duration of ∼120 fs) owing to the dispersions in the fiber bundle are much small indicating that those have little influence on the measurement of carrier relaxation dynamics. In the measurements of κ-(BEDT-TTF)2Cu(NCS)2 under 1.3 kbar at 43 K, we have successfully detected the polarization anisotropy of the carrier relaxation dynamics and estimated the decay time in the same way as the normal measurement.

11.
Yakugaku Zasshi ; 132(7): 831-6, 2012.
Artículo en Japonés | MEDLINE | ID: mdl-22790029

RESUMEN

The protective effects of notoginseng against hepatic damage were investigated in mice. To prepare a model animal of hepatitis, a mixture of lipopolysaccharide and galactosamine (LPS/GAlN) was administered intraperitoneally, leading to the impairment of hepatic function. Extracts of notoginseng or its components (ginsenoside Rb1 and ginsenoside Rg1) were orally administered 2 h before LPS/GalN injection. Eight hours after LPS/GalN injection, blood and liver tissue samples were collected. The levels of serum aspartate amino transferase (AST), alanine aminotransferase (ALT), tumor necrosis factor (TNF)-α, and interferon (IFN)-γ were measured using commercial assay kits. Histologic changes in the tissue samples were also observed after hematoxylin-eosin staining. LPS/GalN administration increased the serum levels of AST and ALT, and histologic changes were noted, indicating hepatic cell damage. Prior to the increase in ALT, the serum levels of TNF-α and IFN-γ were elevated after LPS/GalN injection. Pretreatment of the mice with either notoginseng extract or gensenoside Rb1 and Rg1 attenuated the LPS/GalN-induced hepatic damage markedly. The protective effects of the components against hepatic damage appeared to be less potent than those of the crude extract and prescription of notoginseng. Notoginseng may be clinically useful in patients with hepatitis.


Asunto(s)
Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/tratamiento farmacológico , Galactosamina , Lipopolisacáridos , Panax notoginseng , Fitoterapia , Extractos Vegetales/uso terapéutico , Administración Oftálmica , Alanina Transaminasa/sangre , Animales , Biomarcadores/sangre , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/diagnóstico , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/etiología , Modelos Animales de Enfermedad , Interferón gamma/sangre , Masculino , Ratones , Ratones Endogámicos ICR , Extractos Vegetales/administración & dosificación , Extractos Vegetales/farmacología , Factor de Necrosis Tumoral alfa/sangre
12.
Int Heart J ; 48(1): 79-86, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17379981

RESUMEN

BACKGROUND: In patients with aortic stenosis (AS), the clinical outcome worsens after the development of angina, syncope, and heart failure. This study was performed to elucidate whether the outcome with AS was also poor in patients with diastolic heart failure. METHODS AND RESULTS: Fifty-two patients who had undergone aortic valve replacement (AVR) for AS were retrospectively classified into 3 groups (G) on the basis of LV ejection fraction (EF) and pulmonary wedge pressure (PWP): G-1) normal LVEF, low PWP (EF > or = 45% and PWP < 16 mmHg; n = 35), G-2) normal LVEF, high PWP (EF > or = 45% and PWP > or = 16 mmHg; n = 8), and G-3) low LVEF (EF < 45%; n = 9). Among these 3 groups, we compared the outcome after AVR. None of the patients died after the operation in AS with preserved LVEF irrespective of the PWP, whereas there were 3 cardiac deaths in AS with low EF irrespective of the PWP. CONCLUSIONS: In patients with AS, diastolic heart failure developed in addition to systolic heart failure. The development of LV systolic dysfunction in AS was regarded as poor during the postoperative course, but diastolic heart failure did not affect the outcome. The occurrence of heart failure with preserved systolic function may have a slightly better prognosis and may still be suitable for AVR.


Asunto(s)
Estenosis de la Válvula Aórtica/cirugía , Insuficiencia Cardíaca/etiología , Implantación de Prótesis de Válvulas Cardíacas , Contracción Miocárdica/fisiología , Función Ventricular Izquierda/fisiología , Anciano , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/fisiopatología , Cateterismo Cardíaco , Ecocardiografía Doppler , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Volumen Sistólico/fisiología , Sístole , Factores de Tiempo , Resultado del Tratamiento
13.
J Vet Med Sci ; 68(10): 1093-5, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17085889

RESUMEN

The serum and fecal testosterone (T) concentrations and testicular sizes of two male bharals (Pseudois nayaur) were determined for approximately one year. The profiles of the fecal T concentrations showed a similar tendency as the profiles of serum T concentrations, and there was a significant correlation between serum and fecal T concentrations (r=0.72). T concentrations rose drastically in October and decreased gradually until January. The maximum testicular size was observed between November and January. Semen collected between December and January was excellent in quality and comparable to domestic sheep and goats. The active periods of the testes were synchronized with the early breeding season of females.


Asunto(s)
Heces/química , Ovinos/fisiología , Espermatozoides/fisiología , Testículo/fisiología , Testosterona/metabolismo , Animales , Conservación de los Recursos Naturales , Masculino , Estaciones del Año , Ovinos/anatomía & histología , Ovinos/sangre , Testículo/anatomía & histología , Testosterona/sangre
14.
J Vet Med Sci ; 68(8): 847-51, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16953086

RESUMEN

The purpose of present study was to determine annual changes in serum progesterone (P(4)) concentrations and to clarify basic reproductive characteristics, such as breeding season, estrous cycle, and puberty in female bharals (Pseudois nayaur). Blood was collected from 9 female bharals once or twice weekly for approximately one year. Serum P(4) concentrations were determined by radioimmunoassay. Serum P(4) concentrations showed remarkable and cyclic changes between November/December (winter) and May/June (late spring). The mean estrous cycle was 24.9 +/- 0.5 days. Chasing insistently to other females and discharge of mucus from the vulva were observed around the time when the serum P(4) concentrations began to increase. The chasing behavior and discharge of mucus were considered to be external indicators of estrus in female bharals. Serum P(4) concentrations of a pregnant female had non-cyclic changes, and the values remained high. In this study, all 37 deliveries were between April and September, and about 70% of these were concentrated in May and June. The conception month determined on the day of birth was between October and April for all animals, and the most common month was in December (54%). This month corresponded to an early stage of the period when the serum P(4) concentrations changed cyclically. These results indicate that many female bharals become pregnant at the beginning of the breeding seasons and, if they do not become pregnant, the estrous cycle, about 25 days in length, is repeated.


Asunto(s)
Ciclo Estral/fisiología , Progesterona/sangre , Rumiantes/fisiología , Animales , Ciclo Estral/sangre , Femenino , Masculino , Parto , Rumiantes/sangre , Estaciones del Año
16.
Circulation ; 112(6): 812-8, 2005 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-16061745

RESUMEN

BACKGROUND: Markers of cardiac injury, including troponin-T (TnT), are used to diagnose acute coronary syndrome (ACS); however, markers for plaque instability may be more useful for diagnosing ACS at the earliest stage. Lectin-like oxidized LDL receptor-1 (LOX-1) appears to play crucial roles in the pathogenesis of atherosclerotic plaque rupture and ACS onset. LOX-1 is released in part as soluble LOX-1 (sLOX-1) by proteolytic cleavage. METHODS AND RESULTS: We examined serum sLOX-1 levels in 521 patients, consisting of 427 consecutive patients undergoing coronary angiography, including 80 ACS patients, 173 symptomatic coronary heart disease patients, 122 patients with significant coronary stenosis without ischemia, and 52 patients without apparent coronary atherosclerosis plus 34 patients with noncardiac acute illness and 60 patients with noncardiac chronic illness. Time-dependent changes in sLOX-1 and TnT levels were analyzed in an additional 40 ACS patients. Serum sLOX-1 levels were significantly higher in ACS than the other groups and were associated with ACS as shown by multivariable logistic regression analyses. Given a cutoff value of 1.0 ng/mL, sLOX-1 can discriminate ACS from other groups with 81% and 75% of sensitivity and specificity, respectively. sLOX-1 can also discriminate ACS without ST elevation or abnormal Q waves and ACS without TnT elevation from non-ACS with 91% and 83% of sensitivity, respectively. Peak values of sLOX-1 in ACS were observed earlier than those of TnT. CONCLUSIONS: sLOX-1 appears to be a useful marker for early diagnosis of ACS.


Asunto(s)
Enfermedad Coronaria/sangre , Enfermedad Coronaria/diagnóstico , Receptores Depuradores de Clase E/sangre , Enfermedad Aguda , Anciano , Biomarcadores/sangre , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/sangre , Femenino , Humanos , Lectinas/sangre , Masculino , Persona de Mediana Edad
17.
Artículo en Inglés | MEDLINE | ID: mdl-15142532

RESUMEN

Carbohydrates were extracted from milk of a bearded seal, Erignathus barbatus (Family Phocidae). Free neutral oligosaccharides were separated by gel filtration, anion-exchange chromatography and preparative thin layer chromatography, while free acidic oligosaccharides were separated by gel filtration and then purified by ion exchange chromatography, gel filtration and high performance liquid chromatography. Oligosaccharide structures were determined by 1H-NMR spectroscopy. The structures of the neutral oligosaccharides were as follows; lactose, 2'-fucosyllactose, lacto-N-fucopentaose IV, difucosyl lacto-N-neohexaose and difucosyl decasaccharide which contained a lacto-N-neohexaose unit as well as an additional Gal(beta1-4)GlcNAc(beta1-3) unit and two residues of non-reducing Fuc(alpha1-2). The acidic oligosaccharides were thought to contain an Neu5Ac(alpha2-6) residue linked to GlcNAc or a sulfate linked to Gal at OH-3. The sialyl oligosaccharides and sulfated oligosaccharides had a lacto-N-neohexaose unit and two non-reducing Fuc(alpha1-2) residues and some of them had in addition one or two Gal(beta1-4)GlcNAc(beta1-3) units. The milk oligosaccharides of the bearded seal were compared to those of the harbour seal, which had been studied previously.


Asunto(s)
Leche/química , Oligosacáridos/análisis , Oligosacáridos/química , Phocidae , Animales , Cromatografía Liquida , Femenino , Concentración de Iones de Hidrógeno , Inositol/análisis , Inositol/química , Inositol/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Oligosacáridos/aislamiento & purificación
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