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1.
Int J Mol Sci ; 24(3)2023 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-36768545

RESUMEN

Tissue inhibitors of metalloproteinases (TIMPs) are endogenous matrix metalloproteinase inhibitors. TIMP1 is produced by cancer cells and has pleiotropic activities. However, its role and source in multiple myeloma (MM) are unclear. Here, we evaluated TIMP1 protein and mRNA levels in bone marrow (BM) plasma cells and assessed the effects of TIMP1 expression on fibroblast invasive capacity using three-dimensional spheroid cell invasion assays. TIMP1 mRNA and protein levels were elevated when patients progressed from monoclonal gammopathy of undetermined significance or smouldering myeloma to MM. Furthermore, TIMP1 levels decreased at complete response and TIMP1 protein levels increased with higher international staging. TIMP1 mRNA levels were markedly higher in extramedullary plasmacytoma and MM with t(4;14). Overall survival and post-progression survival were significantly lower in MM patients with high TIMP1 protein. Recombinant TIMP1 did not directly affect MM cells but enhanced the invasive capacity of fibroblasts; this effect was suppressed by treatment with anti-TIMP1 antibodies. Fibroblasts supported myeloma cell invasion and expansion in extracellular matrix. Overall, these results suggested that MM-derived TIMP1 induces the invasive phenotype in fibroblasts and is involved in disease progression. Further studies are required to elucidate the specific roles of TIMP1 in MM and facilitate the development of novel therapies targeting the TIMP1 pathway.


Asunto(s)
Mieloma Múltiple , Humanos , Mieloma Múltiple/genética , Mieloma Múltiple/metabolismo , Inhibidor Tisular de Metaloproteinasa-1/metabolismo , Fibroblastos/metabolismo , ARN Mensajero/metabolismo , Fenotipo , Progresión de la Enfermedad
2.
Rinsho Ketsueki ; 64(3): 203-208, 2023.
Artículo en Japonés | MEDLINE | ID: mdl-37019674

RESUMEN

During laparoscopic cholecystectomy, an 89-year-old man was discovered to have a prolonged APTT. He was transferred to our hospital for a thorough examination because wound bleeding necessitated a reoperation. Based on coagulation factor VIII activity (FVIII:C) of 3.6% and FVIII inhibitor levels of 48.5 BU/ml, he was diagnosed with acquired hemophilia A (AHA). Due to concerns about his advanced age and postoperative infection, immunosuppressive therapy with prednisolone 0.5 mg/kg/day was initiated. His clinical course was favorable, except hemorrhagic shock caused by intramuscular hemorrhage on the right back, although low FVIII inhibitor levels persisted for more than a month; additionally, lower leg edema and increased urinary protein were also observed. He was diagnosed as with AHA and secondary nephrotic syndrome, possibly because of early gastric cancer. As a result, radical endoscopic submucosal dissection (ESD) was performed while a recombinant coagulation factor VIIa preparation was administered. AHA improved rapidly following ESD, and coagulative remission was achieved. Simultaneously, the nephrotic syndrome improved. Because the control of malignant tumors may improve the status of AHA, the timing of malignant tumor intervention must be considered considering the risk of bleeding and infection associated with immunosuppression.


Asunto(s)
Hemofilia A , Síndrome Nefrótico , Neoplasias Gástricas , Masculino , Humanos , Anciano de 80 o más Años , Hemofilia A/tratamiento farmacológico , Factor VIII/uso terapéutico , Síndrome Nefrótico/complicaciones , Neoplasias Gástricas/complicaciones , Prednisolona/uso terapéutico
3.
Rinsho Ketsueki ; 64(1): 60-65, 2023.
Artículo en Japonés | MEDLINE | ID: mdl-36775309

RESUMEN

An 86-year-old Japanese male patient visited a nearby hospital with painful swelling in his left upper and lower limbs 35 days after the second dose of the BNT162b2 mRNA coronavirus disease-2019 (COVID-19) vaccine. He was referred to our hematological department due to a prolonged activated partial thromboplastin time and was urgently admitted. He was diagnosed with acquired hemophilia A (AHA) based on factor VIII (FVIII) activity of 1.7%, FVIII inhibitor of 152.3 BU/ml, and FVIII-binding antibodies detected by enzyme-linked immunosorbent assay. Immunosuppressive therapy with prednisolone (PSL) at 0.5 mg/kg/day was started owing to the risk of infection due to old age and poor activities of daily living. Hemostasis treatment with bypass hemostatic preparations (rFVIIa preparation, FVIIa/FX) was administered for each bleeding event, such as intramuscular and knee joint bleeding, resulting in good hemostatic effects. Coagulative complete remission was achieved on day 69 with PSL treatment; however, FVIII activity decreased with PSL tapering. AHA relapse with rectus abdominis muscle hematoma was observed after the third vaccination. This is the first Japanese report of AHA after COVID-19 vaccination and the world's first case, in which the presence of anti-FVIII-binding antibodies were observed.


Asunto(s)
Vacuna BNT162 , COVID-19 , Hemofilia A , Hemostáticos , Anciano de 80 o más Años , Humanos , Masculino , Actividades Cotidianas , Vacuna BNT162/efectos adversos , COVID-19/prevención & control , Factor VIII/uso terapéutico , Hemofilia A/inducido químicamente , Hemofilia A/terapia , Hemostáticos/uso terapéutico , Prednisolona/uso terapéutico
4.
Rinsho Ketsueki ; 63(1): 55-61, 2022.
Artículo en Japonés | MEDLINE | ID: mdl-35135953

RESUMEN

Neuropsychiatric symptoms comprise one of the five classic symptoms of autoimmune thrombotic thrombocytopenic purpura (aTTP). Although aTTP is typically transient, it is sometimes complicated by cerebral infarction with residual disability. This report presents the case of an 87-year-old man previously admitted to a different hospital with fever and transient consciousness loss. After receiving platelet transfusion with diagnosis of Evans syndrome, he was transferred to our hospital with worsening consciousness disturbance. He was subsequently diagnosed with aTTP with a PLASMIC score of 6 points, ADAMTS13 activity of less than 0.5%, and its inhibitor of 7.4 BU/ml. Platelet count and consciousness were rapidly improved with plasmapheresis and steroids, but motor aphasia emerged. MRI showed multiple cerebral infarctions, including a large infarction in the left frontal lobe. Thus, unfractionated heparin was administered. When his platelet count dropped once again on the 20th day, rituximab was added. The treatment eventually proved to be successful, and his aTTP remained in remission one year after the onset. Treatment for cerebral infarctions was switched to DOAC, and rehabilitation was continued. However, his ADL has not yet recovered. Advances in aTTP treatment have cured many similar cases. Thus, rituximab is now considered a treatment option for refractory cases. However, ischemic organ damage in acute phase and sequelae are observed. Therefore, early diagnosis and novel therapy are required.


Asunto(s)
Púrpura Trombocitopénica Trombótica , Proteína ADAMTS13 , Anciano de 80 o más Años , Infarto Cerebral/diagnóstico por imagen , Infarto Cerebral/tratamiento farmacológico , Infarto Cerebral/etiología , Heparina , Humanos , Masculino , Intercambio Plasmático , Púrpura Trombocitopénica Trombótica/complicaciones , Púrpura Trombocitopénica Trombótica/diagnóstico , Púrpura Trombocitopénica Trombótica/tratamiento farmacológico , Rituximab/uso terapéutico
5.
Rinsho Ketsueki ; 63(10): 1392-1396, 2022.
Artículo en Japonés | MEDLINE | ID: mdl-36351645

RESUMEN

From a young age, a 63-year-old Japanese man had experienced difficulties with hemostasis during tooth extraction and epistaxis and swelling of bruised areas. He had previously been diagnosed with mild hemophilia (FVIII:C 8.5%) at age of 60 due to swelling of a right hip bruise and was administered FVIII concentrate for the first time. He had frequent bleeding around his shoulder joints and was given FVIII concentrates every time, but his hemostasis was poor. He was referred to our hospital because his FVIII activity decreased to<1% and a low-titer inhibitor (2.0 BU/ml) was detected. Because of a shoulder hematoma and new subcutaneous bleeding on both forearms, recombinant FVIIa was used to perform the hemostatic treatment. Following hemostasis, emicizumab was administered subcutaneously every 2 weeks at a dose of 3.0 mg/kg. Approximately 2 months after starting emicizumab, inhibitors were no longer detected, and FVIII activity increased to 8% after 9 months. We encountered a case of mild hemophilia A with an inhibitor that was first diagnosed in old age. The incidence of inhibitors in non-severe hemophilia A is about 10%, and about 70% of those resolves spontaneously. In this case, suppression of bleeding by emicizumab may have contributed to the spontaneous disappearance of the inhibitor.


Asunto(s)
Anticuerpos Biespecíficos , Hemofilia A , Masculino , Humanos , Persona de Mediana Edad , Hemofilia A/tratamiento farmacológico , Hemofilia A/diagnóstico , Factor VIII/uso terapéutico , Anticuerpos Biespecíficos/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Hemorragia/tratamiento farmacológico , Hemorragia/etiología
6.
Nano Lett ; 20(12): 8682-8688, 2020 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-33226819

RESUMEN

Electrostatically defined quantum dots (QDs) in Bernal stacked bilayer graphene (BLG) are a promising quantum information platform because of their long spin decoherence times, high sample quality, and tunability. Importantly, the shape of QD states determines the electron energy spectrum, the interactions between electrons, and the coupling of electrons to their environment, all of which are relevant for quantum information processing. Despite its importance, the shape of BLG QD states remains experimentally unexamined. Here we report direct visualization of BLG QD states by using a scanning tunneling microscope. Strikingly, we find these states exhibit a robust broken rotational symmetry. By using a numerical tight-binding model, we determine that the observed broken rotational symmetry can be attributed to low energy anisotropic bands. We then compare confined holes and electrons and demonstrate the influence of BLG's nontrivial band topology. Our study distinguishes BLG QDs from prior QD platforms with trivial band topology.

7.
Br J Haematol ; 191(5): 755-763, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32386081

RESUMEN

Previous genomic studies have revealed the genomic landscape of myeloma cells. Although some of the genomic abnormalities shown are believed to be correlated to the molecular pathogenesis of multiple myeloma and/or clinical outcome, these correlations are not fully understood. The aim of this study is to elucidate the correlation between genomic abnormalities and clinical characteristics by targeted capture sequencing in the Japanese multiple myeloma cohort. We analysed 154 patients with newly diagnosed multiple myeloma. The analysis revealed that the study cohort consisted of a less frequent hyperdiploid subtype (37·0%) with relatively high frequencies of KRAS mutation (36·4%) and IGH-CCND1 translocation (26·6%) compared with previous reports. Moreover, our targeted capture sequencing strategy was able to detect rare IGH-associated chromosomal translocations, such as IGH-CCND2 and IGH-MAFA. Interestingly, all 10 patients harboured MAX mutations accompanied by 14q23 deletion. The patients with del(17p) exhibited an unfavourable clinical outcome, and the presence of KRAS mutation was associated with shorter survival in patients with multiple myeloma, harbouring IGH-CCND1. Thus, our study provides a detailed landscape of genomic abnormalities, which may have potential clinical application for patients with multiple myeloma.


Asunto(s)
Deleción Cromosómica , Cromosomas Humanos Par 14/genética , Mieloma Múltiple/genética , Proteínas de Neoplasias/genética , Síndrome de Smith-Magenis/genética , Adulto , Cromosomas Humanos Par 17/genética , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad
8.
Acta Haematol ; 143(5): 486-490, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31563916

RESUMEN

Acquired factor V inhibitor (AFVI) results from the formation of autoantibodies to coagulation factor V (FV), and the clinical phenotype can range from asymptomatic laboratory abnormalities to life-threatening bleeds. We describe a 74-year-old man who developed AFVI along with a massive subcutaneous hematoma. He was initially treated with prednisolone (PSL), but AFVI recurred when the dose was reduced after a short period. We subsequently increased the PSL dose and added cyclophosphamide (CY), which resulted in a complete response. We then gradually tapered PSL and stopped CY, and the patient has since remained free of recurrent AFVI symptoms. We monitored FV activity, antigen concentrations, and inhibitor titers of this patient throughout the clinical course. The ratio of FV activity to antigen concentration was low at diagnosis and gradually increased along with the patient's improvement. This ratio might be a useful parameter for evaluating the effects of immunosuppressive therapy in patients with AFVI.


Asunto(s)
Inhibidores de Factor de Coagulación Sanguínea/sangre , Factor V/metabolismo , Hemorragia/diagnóstico , Anciano , Ciclofosfamida/uso terapéutico , Factor V/antagonistas & inhibidores , Hemorragia/tratamiento farmacológico , Hemorragia/etiología , Humanos , Masculino , Prednisolona/uso terapéutico
9.
Int J Mol Sci ; 21(19)2020 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-32992461

RESUMEN

Long noncoding RNAs (lncRNAs) are deregulated in human cancers and are associated with disease progression. Plasmacytoma Variant Translocation 1 (PVT1), a lncRNA, is located adjacent to the gene MYC, which has been linked to multiple myeloma (MM). PVT1 is expressed in MM and is associated with carcinogenesis. However, its role and regulation remain uncertain. We examined PVT1/MYC expression using real-time PCR in plasma cells purified from 59 monoclonal gammopathy of undetermined significance (MGUS) and 140 MM patients. The MM cell lines KMS11, KMS12PE, OPM2, and RPMI8226 were treated with JQ1, an MYC super-enhancer inhibitor, or MYC inhibitor 10058-F4. The expression levels of PVT1 and MYC were significantly higher in MM than in MGUS (p < 0.0001) and were positively correlated with disease progression (r = 0.394, p < 0.0001). JQ1 inhibited cell proliferation and decreased the expression levels of MYC and PVT1. However, 10054-F4 did not alter the expression level of PVT1. The positive correlation between MYC and PVT1 in patients, the synchronous downregulation of MYC and PVT1 by JQ1, and the lack of effect of the MYC inhibitor on PVT1 expression suggest that the expression of these two genes is co-regulated by a super-enhancer. Cooperative effects between these two genes may contribute to MM pathogenesis and progression.


Asunto(s)
Carcinogénesis/genética , Proteínas de Ciclo Celular/genética , Progresión de la Enfermedad , Gammopatía Monoclonal de Relevancia Indeterminada/genética , Mieloma Múltiple/genética , ARN Largo no Codificante/genética , Factores de Transcripción/genética , Acetamidas/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Azepinas/farmacología , Proteínas de Ciclo Celular/antagonistas & inhibidores , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Silenciador del Gen , Humanos , Masculino , Persona de Mediana Edad , Gammopatía Monoclonal de Relevancia Indeterminada/patología , Mieloma Múltiple/patología , Células Plasmáticas/metabolismo , Proteínas Proto-Oncogénicas c-myc/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-myc/genética , Tiazoles/farmacología , Factores de Transcripción/antagonistas & inhibidores , Triazoles/farmacología , Adulto Joven
10.
J Am Chem Soc ; 140(43): 14046-14049, 2018 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-30336019

RESUMEN

Surface structure relaxation of organic semiconductors affects the properties of organic devices, although such relaxation has not been well explored. Only two examples have been experimentally reported; tetracene shows a large surface relaxation, while rubrene exhibits no relaxation. Therefore, a systematic investigation of the surface relaxation is conducted on [ n]phenacenes ( n = 5, 7, and 9). Electron density analyses are performed based on the synchrotron surface X-ray scattering with the aid of first-principles calculations. The results show little surface relaxation in [ n]phenacenes.

11.
Nanotechnology ; 29(45): 455201, 2018 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-30156565

RESUMEN

With the view towards future non-volatile random access memories that can be integrated at a large scale, extensive study on resistive switching (RS) devices arranged in a crossbar array is currently underway. Although the crossbar array architecture offers relatively simple and acceptable scalability, the presence of sneak current is recognized as a critical issue that needs to be resolved at device level. In addressing this issue, we demonstrate a new type of RS device fabricated by combining graphene oxide (G-O) and zinc oxide (ZnO) with highly asymmetric current-voltage (I-V) characteristics depending on the polarity of bias voltage. The distinctive highly asymmetric I-V characteristics result from the presence of a hetero-junction interface formed between the G-O and ZnO layers. This hetero-junction manifests resistance in the range of GΩ under both forward and reverse bias voltage when the device is in the OFF state, in contrast, when the device is in the ON state, it exhibits resistance in the range of MΩ or kΩ under forward bias and GΩ under reverse bias. We propose to employ demonstrated RS devices with highly asymmetric I-V characteristics to mitigate adverse effects of the sneak current.

12.
J Pediatr Hematol Oncol ; 40(3): e171-e175, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29200172

RESUMEN

We describe a rare case of chronic active Epstein-Barr virus (CAEBV) infection, with infiltration of the skeletal muscle. A 19-year-old woman with swollen cervical lymph nodes and a fever was referred to our hospital. Swelling of the trapezium muscle and elevation of creatinine kinase level were observed. Biopsy results of the brachialis muscle revealed infiltration of Epstein-Barr virus (EBV)-encoded RNA-positive CD8 T lymphocytes. The EBV virus load in the peripheral blood was high, and EBV monoclonality was determined by Southern blot analysis. Owing to the rarity of CAEBV with skeletal muscle infiltration, this case alerts physicians to the potential diagnostic pitfalls of CAEBV.


Asunto(s)
Linfocitos T CD8-positivos/virología , Infecciones por Virus de Epstein-Barr/patología , Músculo Esquelético/patología , Enfermedad Crónica , Femenino , Herpesvirus Humano 4 , Humanos , Miositis/patología , Miositis/virología , Adulto Joven
13.
Br J Haematol ; 179(3): 449-460, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28770558

RESUMEN

Extramedullary myeloma (EMM) occurs when myeloma develops outside the bone marrow; it often develops after chemotherapy and is associated with the acquisition of chemo-resistance and a fatal course. The mechanisms underlying extramedullary spread have not yet been fully elucidated. MALAT1 is a highly abundantly and ubiquitously expressed long non-coding RNA that plays important roles in cancer metastasis. The aims of this study were to clarify the association of MALAT1 with EMM and to elucidate the underlying mechanism of EMM formation under chemotherapeutic pressure. MALAT1 expression was significantly higher in multiple myeloma (MM) than in monoclonal gammopathy of undetermined significance. Furthermore, MALAT1 expression was markedly higher in EMM compared with that in corresponding intramedullary myeloma cells. A higher MALAT1 level was associated with shorter overall and progression-free survival. MALAT1 expression level was positively correlated with expression of HSP90AA1, HSP90AB1 and HSP90B1 but not with TP53 expression. MALAT1 was significantly upregulated by bortezomib and doxorubicin. Considering the known functions of MALAT1, our results suggest that it acts as a stress response gene that is upregulated by chemotherapy, thereby linking chemotherapy to EMM formation. Elucidating the biological implication of long non-coding RNA contributes to deeper understanding concerning the pathogenesis and investigation of novel therapeutic targets for MM.


Asunto(s)
Biomarcadores de Tumor/genética , Mieloma Múltiple/patología , ARN Largo no Codificante/genética , Antineoplásicos/farmacología , Biomarcadores de Tumor/metabolismo , Bortezomib/farmacología , Progresión de la Enfermedad , Doxorrubicina/farmacología , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Gammopatía Monoclonal de Relevancia Indeterminada/genética , Gammopatía Monoclonal de Relevancia Indeterminada/metabolismo , Mieloma Múltiple/genética , Pronóstico , ARN Largo no Codificante/biosíntesis , ARN Neoplásico/biosíntesis , ARN Neoplásico/genética , Estrés Fisiológico/genética , Análisis de Supervivencia , Células Tumorales Cultivadas
14.
Rinsho Ketsueki ; 58(6): 613-618, 2017.
Artículo en Japonés | MEDLINE | ID: mdl-28679991

RESUMEN

Acquired von Willebrand syndrome (AvWS) is a rare bleeding disorder with laboratory findings resembling those of congenital von Willebrand disease. AvWS usually occurs in association with a variety of underlying disorders, such as lymphoproliferative disease or cardiovascular disease, but autoimmune AvWS is very rare. We now describe the case of a 42-year-old woman with autoimmune AvWS with concurrent antiphospholipid syndrome (APS). The patient was suffering from epistaxis and menorrhagia from few years prior to referral. She was referred to our hospital because of Activated Partial Thromboplastin Time (APTT) prolongation. Autoimmune AvWS was diagnosed as hemostatic and immunological analyses showed very low (<6%) levels of vWF ristocetin cofactor activity, low (6%) levels of vWF antigen and the presence of anti-vWF antibodies (IgG1 and IgG2) as well as antiphospholipid antibodies. Steroid therapy led to prompt AvWS remission, but deep vein thrombosis occurred in the left leg, on day 36 and APS was diagnosed. A combination of steroid and anti-coagulant was given for approximately 3 years. Thrombosis has not recurred; but AvWS re-exacerbated with steroid tapering. This is the first case report of autoimmune AvWS concurrent with APS, and the long-term disease course described here can be beneficial to clinicians.


Asunto(s)
Síndrome Antifosfolípido/complicaciones , Enfermedades de von Willebrand/etiología , Adulto , Femenino , Humanos , Resultado del Tratamiento , Enfermedades de von Willebrand/tratamiento farmacológico
15.
Acta Haematol ; 136(3): 174-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27561697

RESUMEN

Epstein-Barr virus-associated lymphoproliferative disorder (EBV-LPD) is a currently emerging serious complication in immunosuppressed patients, especially in allogeneic transplant recipients. Several fatal cases of EBV-LPD have been reported in aplastic anemia (AA) patients receiving immunosuppressive therapy (IST) with antithymocyte globulin (ATG) plus cyclosporine A (CsA), but no appropriate prophylactic or therapeutic strategy has been established. Herein, we describe a 29-year-old man whose EBV-LPD was successfully treated with rituximab. He received IST with ATG plus CsA for hepatitis-associated AA. EBV-DNA in plasma, which was not detectable before IST, gradually increased after IST initiation. A high fever and systemic lymphadenopathy developed 31 days after IST initiation. An EBV-DNA titer of 5.7 × 105 copies/µl was detected, and a diagnosis of EBV-LPD was made. Although discontinuation of IST was not effective, a single dose of rituximab on day 33 resolved the clinical symptoms and completely eliminated EBV-DNA. Even after restarting CsA administration, no elevation of EBV-DNA was observed, and his complete blood cell count had fully recovered 1 year after IST. This case suggests that this treatment strategy for EBV-LPD with EBV-DNA monitoring and rituximab administration, which has been recommended in allogeneic transplant recipients, may also be useful in the context of AA patients receiving IST.


Asunto(s)
Herpesvirus Humano 4/genética , Rituximab , Anemia Aplásica , Infecciones por Virus de Epstein-Barr , Humanos , Trastornos Linfoproliferativos/diagnóstico
16.
Langmuir ; 31(28): 7852-9, 2015 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-26126182

RESUMEN

The structural properties of optically thin (15 nm) silver (Ag) films deposited on SiO2/Si(100) substrates with a germanium (Ge) nucleation layer were studied. The morphological and crystallographical characteristics of Ag thin films with different Ge nucleation layer thicknesses were assessed by cross-sectional transmission electron microscopy (XTEM), reflection high-energy electron diffraction (RHEED), X-ray diffractometry (XRD), grazing incidence X-ray diffractometry (GIXRD), X-ray reflection (XRR), and Fourier transform infrared spectroscopy (FTIR). The surface roughness of Ag thin films was found to decrease significantly by inserting a Ge nucleation layer with a thickness in the range of 1 to 2 nm (i.e., smoothing mode). However, as the Ge nucleation layer thickness increased beyond 2 nm, the surface roughness increased concomitantly (i.e., roughing mode). For the smoothing mode, the role of the Ge nucleation layer in the Ag film deposition is discussed by invoking the surface energy of Ge, the bond dissociation energy of Ag-Ge, and the deposition mechanisms of Ag thin films on a given characteristic Ge nucleation layer. Additionally, Ge island formation, the precipitation of Ge from Ag-Ge alloys, and the penetration of Ge into SiO2 are suggested for the roughing mode. This demonstration of ultrasmooth Ag thin films would offer an advantageous material platform with scalability for applications such as optics, plasmonics, and photonics.

17.
Heart Vessels ; 29(3): 308-12, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-23686321

RESUMEN

Although detecting left ventricular thrombus in anterior myocardial infarction is important for the prevention of embolic events, imaging of apical thrombus is often difficult using conventional echocardiography. We examined whether contrast echocardiography improves sensitivity and specificity in detecting thrombus in the left ventricle in comparison with conventional echocardiography alone in patients with anterior myocardial infarction. Participants in this single-center prospective study comprised 392 patients with anterior myocardial infarction admitted between 2000 and 2006. After conventional echocardiography, all patients underwent contrast echocardiography (left ventricular opacification and myocardial contrast echocardiography) during intravenous drip infusion of contrast media at rest. Left ventricular thrombus was diagnosed based on left ventriculography or multidetector-row computed tomography (MDCT). Mural left ventricular thrombus was confirmed by left ventriculography and/or MDCT in 32 of 393 patients (8 %). Sensitivity and specificity of conventional echocardiography alone were 88 % and 96 %, respectively, compared with 100 % each with contrast echocardiography. Among the 32 patients with left ventricular thrombus, 25 patients (78 %) showed no perfusion in the anterior wall on myocardial contrast echocardiography, even with a four-beat interval. In conclusion, contrast echocardiography offers a clinically feasible and useful method for noninvasively evaluating left ventricular thrombus in anterior myocardial infarction.


Asunto(s)
Infarto de la Pared Anterior del Miocardio/complicaciones , Medios de Contraste , Cardiopatías/diagnóstico por imagen , Polisacáridos , Trombosis/diagnóstico por imagen , Anciano , Medios de Contraste/administración & dosificación , Estudios de Factibilidad , Femenino , Cardiopatías/etiología , Humanos , Infusiones Intravenosas , Japón , Masculino , Tomografía Computarizada Multidetector , Polisacáridos/administración & dosificación , Valor Predictivo de las Pruebas , Estudios Prospectivos , Trombosis/etiología , Ultrasonografía
18.
Nano Lett ; 13(7): 3213-7, 2013 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-23746124

RESUMEN

Highly reproducible bipolar resistance switching was recently demonstrated in a composite material of Pt nanoparticles dispersed in silicon dioxide. Here, we examine the electrical performance and scalability of this system and demonstrate devices with ultrafast (<100 ps) switching, long state retention (no measurable relaxation after 6 months), and high endurance (>3 × 10(7) cycles). A possible switching mechanism based on ion motion in the film is discussed based on these observations.

19.
J Phys Condens Matter ; 36(33)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38729207

RESUMEN

We present an order-Nquantum transport calculation methodology to evaluate thermoelectric transport coefficients, such as electric conductivity and Seebeck coefficient. Different from a conventional method using the electric conductivity spectrum, it obtains the coefficients directly from the correlation function between heat and electric current based on linear response theory. As an example, we apply the methodology to a two-dimensional square-lattice model with static disorder and confirm that the calculated results are consistent with those obtained by the conventional method. The proposed methodology provides an effective approach to evaluate the thermoelectric performance of micron-scale materials based on quantum mechanics from an atomistic viewpoint.

20.
Int J Hematol ; 117(4): 563-577, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36522589

RESUMEN

Human endogenous retroviruses (HERVs) are retrotransposons that infect human germline cells and occupy 5-8% of the human genome. Their expression, though inhibited by mutation, deletion, and epigenetic mechanisms under normal conditions, is associated with diseases including cancer. This study aimed to clarify the association between HERVs and multiple myeloma (MM) progression. We found that HERV-K envelope (env) and long-term repeat (LTR) expression was statistically significantly higher within plasma cells in MM than in monoclonal gammopathy of undetermined significance or controls. HERV-K env knockdown increased proliferation in the MM.1S cell line and decreased the expression of the tumor suppressor genes TP53 and CDKN1A. TP53 and CDKN1A were highly expressed in MM, and their expression was correlated with HERV-K expression. HERV-K knockdown reduced apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3F, 3G, and 3H expression by 10-20% in MM.1S cells. The anti-retroviral agents nevirapine and nelfinavir suppressed proliferation and increased HERV-K expression in MM cell lines. Our results suggest that HERV-K is involved in MM progression, but its role is likely to go beyond promoting cell proliferation. Clarifying the role of HERV-K in MM will lead to the discovery of novel treatment strategies and supply new insights into MM pathogenesis.


Asunto(s)
Retrovirus Endógenos , Mieloma Múltiple , Humanos , Retrovirus Endógenos/genética , Mieloma Múltiple/genética , Relevancia Clínica
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