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1.
Circ J ; 85(3): 264-271, 2021 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-33431721

RESUMEN

BACKGROUND: Coronary artery spasms (CASs), which can cause angina attacks and sudden death, have been recently reported during catheter ablation. The aim of the present study was to report the incidence, characteristics, and prognosis of CASs related to atrial fibrillation (AF) ablation procedures.Methods and Results:The AF ablation records of 22,232 patients treated in 15 Japanese hospitals were reviewed. CASs associated with AF ablation occurred in 42 of 22,232 patients (0.19%). CASs occurred during ablation energy applications in 21 patients (50%). CASs also occurred before ablation in 9 patients (21%) and after ablation in 12 patients (29%). The initial change in the electrocardiogram was ST-segment elevation in the inferior leads in 33 patients (79%). Emergency coronary angiography revealed coronary artery stenosis and occlusions, which were relieved by nitrate administration. No air bubbles were observed. A comparison of the incidence of CASs during pulmonary vein isolation between the different ablation energy sources revealed a significantly higher incidence with cryoballoon ablation (11/3,288; 0.34%) than with radiofrequency catheter, hot balloon, or laser balloon ablation (8/18,596 [0.04%], 0/237 [0%], and 0/111 [0%], respectively; P<0.001). CASs most often occurred during ablation of the left superior pulmonary vein. All patients recovered without sequelae. CONCLUSIONS: CASs related to AF ablation are rare, but should be considered as a dangerous complication that can occur anytime during the periprocedural period.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Vasoespasmo Coronario , Venas Pulmonares , Fibrilación Atrial/epidemiología , Fibrilación Atrial/cirugía , Ablación por Catéter/efectos adversos , Vasoespasmo Coronario/epidemiología , Vasoespasmo Coronario/etiología , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/cirugía , Humanos , Incidencia , Venas Pulmonares/cirugía , Espasmo , Resultado del Tratamiento
2.
Pediatr Res ; 84(5): 733-742, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30188508

RESUMEN

BACKGROUND: Left ventricular noncompaction (LVNC) is a primary cardiomyopathy with heterogeneous genetic origins. The aim of this study was to elucidate the role of sarcomere gene variants in the pathogenesis and prognosis of LVNC. METHODS AND RESULTS: We screened 82 Japanese patients (0-35 years old), with a diagnosis of LVNC, for mutations in seven genes encoding sarcomere proteins, by direct DNA sequencing. We identified variants in a significant proportion of cases (27%), which were associated with poor prognosis (p = 0.012), particularly variants in TPM1, TNNC1, and ACTC1 (p = 0.012). To elucidate the pathological role, we developed and studied human-induced pluripotent stem cells (hiPSCs) from a patient carrying a TPM1 p.Arg178His mutation, who underwent heart transplantation. These cells displayed pathological changes, with mislocalization of tropomyosin 1, causing disruption of the sarcomere structure in cardiomyocytes, and impaired calcium handling. Microarray analysis indicated that the TPM1 mutation resulted in the down-regulation of the expression of numerous genes involved in heart development, and positive regulation of cellular process, especially the calcium signaling pathway. CONCLUSIONS: Sarcomere genes are implicated as genetic triggers in the development of LVNC, regulating the expression of numerous genes involved in heart development, or modifying the severity of disease.


Asunto(s)
Ventrículos Cardíacos/patología , Sarcómeros/genética , Adolescente , Adulto , Pueblo Asiatico/genética , Señalización del Calcio , Niño , Preescolar , Femenino , Ventrículos Cardíacos/metabolismo , Humanos , Lactante , Recién Nacido , Japón , Masculino , Mutación , Pronóstico , Sarcómeros/metabolismo , Adulto Joven
3.
Arterioscler Thromb Vasc Biol ; 37(1): 66-74, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27765767

RESUMEN

OBJECTIVE: UVB irradiation is an established treatment for immunoinflammatory cutaneous disorders and has been shown to suppress cutaneous and systemic inflammatory diseases through modulation of the adaptive immune response. However, it remains unknown whether UVB irradiation prevents an immunoinflammatory disease of arteries such as atherosclerosis. APPROACH AND RESULTS: Here, we show that UVB exposure inhibits the development and progression of atherosclerosis in atherosclerosis-prone mice by expanding and enhancing the functional capacity of CD4+ forkhead box P3+ regulatory T cells and regulating proatherogenic T-cell responses. Experimental studies in Langerhans cell-depleted mice revealed that epidermal Langerhans cells play a critical role in UVB-dependent induction of CD4+ forkhead box P3+ regulatory T cells, suppression of proatherogenic T-cell responses, and prevention of atherosclerotic plaque development. CONCLUSIONS: Our findings suggest the skin immune system as a novel therapeutic target for atherosclerosis and provide a novel strategy for the treatment and prevention of atherosclerosis.


Asunto(s)
Aorta/efectos de la radiación , Enfermedades de la Aorta/prevención & control , Aterosclerosis/prevención & control , Inflamación/prevención & control , Piel/efectos de la radiación , Linfocitos T Reguladores/efectos de la radiación , Rayos Ultravioleta , Animales , Aorta/inmunología , Aorta/metabolismo , Aorta/patología , Enfermedades de la Aorta/inmunología , Enfermedades de la Aorta/metabolismo , Enfermedades de la Aorta/patología , Apolipoproteínas E/deficiencia , Apolipoproteínas E/genética , Aterosclerosis/inmunología , Aterosclerosis/metabolismo , Aterosclerosis/patología , Células Cultivadas , Modelos Animales de Enfermedad , Factores de Transcripción Forkhead/inmunología , Factores de Transcripción Forkhead/metabolismo , Predisposición Genética a la Enfermedad , Inflamación/inmunología , Inflamación/metabolismo , Inflamación/patología , Células de Langerhans/inmunología , Células de Langerhans/metabolismo , Células de Langerhans/efectos de la radiación , Activación de Linfocitos/efectos de la radiación , Ratones Noqueados , Fenotipo , Placa Aterosclerótica , Transducción de Señal/efectos de la radiación , Piel/inmunología , Piel/metabolismo , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo
4.
Appl Opt ; 56(17): 4917, 2017 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-29047635

RESUMEN

This publisher's note corrects a value in Table 3 in [Appl. Opt.56, 4474 (2017)APOPAI0003-693510.1364/AO.56.004474].

5.
Appl Opt ; 56(15): 4474-4479, 2017 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-29047878

RESUMEN

Double random phase encoding (DRPE) is a classical optical symmetric-key encryption method. DRPE prevents the key length from being determined because of its redundancy between encryption and decryption, unlike digital symmetric-key cryptographies. In our study, we numerically analyzed the key length of DRPE based on key-space analysis. We estimated the key length of DRPE by calculating the inverse value of the cumulative probability of the normal distribution that was estimated from samples of DRPE and then discuss security against brute-force attacks.

6.
J Anesth ; 31(5): 789-793, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28634641

RESUMEN

In ultrasound-guided central venous catheterization, there is no standard technique either for the needle tip visualization or for the adequate needle angle and entry to the skin with short-axis view under out-of-plane technique. In the present study, we propose a novel technique named "stepwise flashing with triangulation", and the efficacy of this technique is assessed. Before and after a didactic session in which the technique was explained, 12 novice residents were asked to position the needle tip on or into the imitation vessels and to avoid deeper penetration by using an agar tissue phantom with ultrasound guidance. "Stepwise flashing" technique was for stepwise visualization of the needle tip, and "triangulation" technique was for adequate needle angle and entry to the skin. After the session, the success rate was increased and a deeper penetration rate was decreased. This technique will help us to facilitate vascular access and to avoid complications in clinical settings.


Asunto(s)
Cateterismo Venoso Central/métodos , Internado y Residencia , Ultrasonografía Intervencional/métodos , Humanos , Agujas , Fantasmas de Imagen , Ultrasonografía/métodos
7.
Masui ; 65(1): 82-5, 2016 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-27004391

RESUMEN

We present two patients developing intraoperative massive bleeding and showed ischemic changes in the electrocardiogram and circulatory collapse accompanied by severe anemia owing to the delay of red blood cell concentrate transfusion. One patient underwent hepatectomy and the other pancreaticoduodenectomy. Their lowest hemoglobin concentration was around 2 g x dl(-1), and they showed ischemic changes in the electrocardiogram and severe decreases in blood pressure. The former received compatible red blood cell concentrate and the latter received uncrossmatched same blood group red blood cell concentrate immediately, and their electrocardiogram and blood pressure quickly improved. To avoid life-threatening anemia, emergency red blood cell concentrate transfusion including compatible different blood group transfusion should be applied for intraoperative massive bleeding.


Asunto(s)
Anemia/etiología , Pérdida de Sangre Quirúrgica , Electrocardiografía , Transfusión de Eritrocitos , Choque/etiología , Anciano , Humanos , Masculino
8.
Appl Opt ; 53(28): 6435-43, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25322230

RESUMEN

Classical double-random phase encoding (C-DRPE) is an optical symmetric-key encryption technique. C-DRPE is reported to be vulnerable to a known-plaintext attack (KPA) that uses a phase retrieval algorithm. However, although phase-only DRPE (PO-DRPE) is reported to be more resistant to KPAs than C-DRPE, it is not obvious yet that PO-DRPE is sufficiently resistant to a KPA under any condition, because the vulnerability to KPA varies depending on various factors, such as the number of the known plaintext-ciphertext pairs that are given for the KPA, or the gray level of the known-plaintext image (i.e., binary or multivalued image). In this paper, we investigate the resistance of C-DRPE and PO-DRPE to KPA under various conditions related to the number of known plaintext-ciphertext pairs and to the gray level of the known-plaintext image.

9.
Appl Opt ; 53(14): 2956-63, 2014 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-24922013

RESUMEN

The security of important information captured by sensors and cameras is currently a growing concern as information theft via techniques such as side-channel attacks become increasingly more prevalent. Double random phase encoding (DRPE) is an optical encryption method based on optical Fourier transform that is currently being used to implement secure coherent optical systems. In this paper, we propose a new DRPE implementation for incoherent optical systems based on integral photography that can be applied to "encrypted imaging (EI)" to optically encrypt an image before it is captured by an image sensor. Because the proposed incoherent DRPE is constituted from conventional DRPE by rewriting the optical encryption via discretization and Euler's formula, its security level is the same as that of conventional DRPE. The results of an experiment in which we encrypted a plaintext image optically and then decrypted it numerically demonstrate that our proposed incoherent optical security system is feasible.

10.
Appl Opt ; 52(6): 1276-83, 2013 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-23435000

RESUMEN

Although initial research shows that double-random phase encoding (DRPE) is vulnerable to known-plaintext attacks that use phase retrieval algorithms, subsequent research has shown that phase-only DRPE, in which the Fourier amplitude component of an image encrypted with classical DRPE remains constant, is resistant to attacks that apply phase retrieval algorithms. Herein, we numerically analyze the key-space of DRPE and investigate the distribution property of decryption keys for classical and phase-only DRPE. We determine the difference in the distribution property of successful decryption keys for these DRPE techniques from the numerical analysis results and then discuss the security offered by them.

11.
Artículo en Inglés | MEDLINE | ID: mdl-37981100

RESUMEN

OBJECTIVE: This study aimed to explore the therapeutic potential of human induced pluripotent stem cell (hiPSC)-derived cardiac tissues (HiCTs) in the emerging approach of bridge to recovery for severe heart failure with ventricular assist devices. We used a rat model of heterotopic heart transplantation (HTx) to mimic ventricular assist device support and heart unloading. METHODS: HiCTs were created by inserting gelatin hydrogel microspheres between cell sheets made from hiPSC-derived cardiovascular cells. Male athymic nude rats underwent myocardial infarction (MI) and were divided into the following groups: MI (loaded, untreated control), MI + HTx (unloaded, untreated control), MI + HTx + HiCT (unloaded, treated), and MI + HiCT (loaded, treated). HiCTs were placed on the epicardium of the heart in treated groups. We evaluated HiCT engraftment, fibrosis, and neovascularization using histologic analysis. RESULTS: After 4 weeks, HiCTs successfully engrafted in 5 of 6 rats in the MI + HTx + HiCT group (83.3%). The engrafted HiCT area was greater under unloaded conditions (MI + HTx + HiCT) than loaded conditions (MI + HiCT) (P < .05). MI + HTx + HiCT had a significantly smaller infarct area compared with MI and MI + HTx. The MI + HTx + MiCT group exhibited greater vascular density in the border zone than MI and MI + HTx. HiCT treatment suppressed cardiomyocyte atrophy due to left ventricular unloading (P = .001). The protein level of muscle-specific RING finger 1, an atrophy-related ubiquitin ligase, was lower in the MI + HTx + HiCT group than in MI + HTx (P = .036). CONCLUSIONS: Transplanting HiCTs into ischemic hearts under unloaded conditions promoted engraftment, neovascularization, attenuated infarct remodeling, and suppressed myocyte atrophy. These results suggest that HiCT treatment could contribute to future advancements in bridge to recovery.

12.
Arterioscler Thromb Vasc Biol ; 31(9): 1963-72, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21817104

RESUMEN

OBJECTIVE: Eicosapentaenoic acid (EPA) has been shown to have beneficial effects on cardiovascular diseases, although the precise mechanism is unknown. We investigated the effect of EPA on the regression of atherosclerosis. METHODS AND RESULTS: LDL-receptor-deficient mice were fed a high-cholesterol diet for 8 weeks to build up aortic sinus atherosclerotic lesions and then were fed a normal diet with or without 5% EPA for 4 weeks. Atherosclerotic lesions were histologically assessed, and immunologic assays were performed. EPA treatment significantly regressed atherosclerosis (-22.7%, P<0.05) and decreased the content of macrophages, CD4(+) T cells, and dendritic cells (DCs) in atherosclerotic lesions, though only changing the chow never induced the regression. Flow cytometric analysis revealed that EPA increased immature DCs (CD11c(+) CD80(-) CD86(-)), increased the indoleamine 2,3-dioxygenase (IDO) in DCs, and decreased the number of CD4(+) T cells. In the presence of the IDO inhibitor, the beneficial effects of EPA on regression were inhibited, suggesting that the effect of EPA was mainly mediated through IDO. CONCLUSIONS: In addition to lowering plasma cholesterol, EPA regressed atherosclerosis probably due to modulation of DC phenotype and reduction in T cell numbers. The present findings might partly explain the beneficial effects of EPA in clinics and support clinical evidence.


Asunto(s)
Aterosclerosis/tratamiento farmacológico , Células Dendríticas/fisiología , Ácido Eicosapentaenoico/administración & dosificación , Receptores de LDL/deficiencia , Administración Oral , Animales , Aterosclerosis/inmunología , Citocinas/genética , Ácido Eicosapentaenoico/farmacología , Indolamina-Pirrol 2,3,-Dioxigenasa/fisiología , Masculino , Ratones , Fenotipo , ARN Mensajero/análisis , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología
13.
Arterioscler Thromb Vasc Biol ; 30(12): 2495-503, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20930170

RESUMEN

OBJECTIVE: To determine whether the administration of an active form of vitamin D(3) (calcitriol) could prevent atherosclerosis through anti-inflammatory actions. METHODS AND RESULTS: Recent clinical studies have shown that lack of vitamin D(3) is a risk factor for cardiovascular events. Oral calcitriol administration decreased atherosclerotic lesions, macrophage accumulation, and CD4(+) T-cell infiltration at the aortic sinus, when compared with the corresponding observations in control mice. We observed a significant increase in Foxp3(+) regulatory T cells and a decrease in CD80(+)CD86(+) dendritic cells (DCs) in the mesenteric lymph nodes, spleen, and atherosclerotic lesions in oral calcitriol-treated mice in association with increased interleukin 10 and decreased interleukin 12 mRNA expression. CD11c(+) DCs from the calcitriol group showed reduced proliferative activity of T lymphocytes, suggesting the suppression of DC maturation. Neutralization of CD25 in vivo revealed that calcitriol inhibited atherosclerosis mainly in a regulatory T cell-dependent manner but also partly because of a decrease in DC maturation. CONCLUSIONS: Oral calcitriol treatment could prevent the development of atherosclerosis by changing the function or differentiation of DCs and regulatory T cells. These findings suggest that intestinal and systemic immune modulation by calcitriol may be a potentially valuable therapeutic approach against atherosclerosis.


Asunto(s)
Antiinflamatorios/administración & dosificación , Enfermedades de la Aorta/prevención & control , Aterosclerosis/prevención & control , Calcitriol/administración & dosificación , Células Dendríticas/efectos de los fármacos , Tolerancia Inmunológica/efectos de los fármacos , Intestino Delgado/efectos de los fármacos , Linfocitos T Reguladores/efectos de los fármacos , Administración Oral , Animales , Enfermedades de la Aorta/genética , Enfermedades de la Aorta/inmunología , Enfermedades de la Aorta/patología , Apolipoproteínas E/deficiencia , Apolipoproteínas E/genética , Aterosclerosis/genética , Aterosclerosis/inmunología , Aterosclerosis/patología , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Antígeno CD11c/metabolismo , Células Cultivadas , Células Dendríticas/inmunología , Modelos Animales de Enfermedad , Femenino , Factores de Transcripción Forkhead/metabolismo , Regulación de la Expresión Génica , Tolerancia Inmunológica/genética , Mediadores de Inflamación/metabolismo , Interleucina-10/genética , Interleucina-12/genética , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Intestino Delgado/inmunología , Ganglios Linfáticos/efectos de los fármacos , Ganglios Linfáticos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , ARN Mensajero/metabolismo , Bazo/efectos de los fármacos , Bazo/inmunología , Linfocitos T Reguladores/inmunología
14.
Am J Case Rep ; 22: e931247, 2021 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-34455414

RESUMEN

BACKGROUND Post-cardiac injury syndrome, including pleural effusion as a delayed complication of permanent pacemaker implantation, has rarely been reported. To resolve pleural effusion, prolonged chest tube placement is often required. Anti-inflammatory agents combined with diuretics are also often prescribed. Saireito, a Japanese herbal medication, which is a combination of Goreisan and Shousaikoto, has both anti-inflammatory and water-modulation properties and has been used for edema (lymph edema, cerebral edema) and inflammation (chronic nephritis). CASE REPORT We describe a 71-year-old woman with a history of syncope and bradycardia who underwent dual permanent pacemaker implantation (placed in the right chest because of a persistent left superior vena cava) without complications. Two months later, she came to the hospital as an outpatient with a dry cough, and was diagnosed with right-sided pleural effusion. A pleural fluid analysis revealed exudative effusion, according to Light's criteria. The fluid was negative for infectious etiology. Chest X-ray, computed tomography, and echocardiography revealed no signs of pericardial effusion or perforation of the pacemaker lead to outside the heart. The pleural effusion persisted despite use of anti-inflammatory medication for several weeks and diuretics for a short period. Saireito was administered with good response; the pleural effusion resolved completely and there was no deterioration of renal function. CONCLUSIONS The present case highlights the clinical significance of Saireito as an effective therapeutic agent for late-onset pacemaker-related pleural effusion, without adverse effects such as renal dysfunction.


Asunto(s)
Marcapaso Artificial , Derrame Pleural , Anciano , Medicamentos Herbarios Chinos , Femenino , Humanos , Japón , Medicina Kampo , Derrame Pleural/etiología , Derrame Pleural/terapia , Vena Cava Superior
15.
Circulation ; 120(20): 1996-2005, 2009 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-19884470

RESUMEN

BACKGROUND: Accumulating evidence suggests that several subsets of regulatory T cells that actively mediate immunologic tolerance play crucial roles in atherogenesis. Recently, orally administered anti-CD3 monoclonal antibody has been shown as an inducer of novel regulatory T cells expressing latency-associated peptide (LAP) on their surface, which potently prevents systemic autoimmunity. In the present study, we hypothesized that oral anti-CD3 antibody treatment may inhibit atherosclerosis in mice. METHODS AND RESULTS: Six-week-old apolipoprotein E-deficient mice on a standard diet were orally given anti-CD3 antibody or control immunoglobulin G on 5 consecutive days, and atherosclerosis was assessed at age 16 weeks. Oral administration of anti-CD3 antibody significantly reduced atherosclerotic lesion formation and accumulations of macrophages and CD4(+) T cells in the plaques compared with controls. We observed a significant increase in LAP(+) cells and CD25(+)Foxp3(+) cells in the CD4(+) T-cell population in anti-CD3-treated mice, in association with increased production of the antiinflammatory cytokine transforming growth factor-beta and suppressed T-helper type 1 and type 2 immune responses. Neutralization of transforming growth factor-beta in vivo abrogated the preventive effect of oral anti-CD3 antibody. CONCLUSIONS: Our findings indicate the atheroprotective role of oral anti-CD3 antibody treatment in mice via induction of a regulatory T-cell response. These findings suggest that oral immune modulation may represent an attractive therapeutic approach to atherosclerosis.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Aterosclerosis/inmunología , Aterosclerosis/prevención & control , Complejo CD3/inmunología , Linfocitos T Reguladores/inmunología , Administración Oral , Animales , Anticuerpos Monoclonales/inmunología , Apolipoproteínas E/genética , Aterosclerosis/genética , Autoinmunidad/efectos de los fármacos , Macrófagos/inmunología , Masculino , Ratones , Ratones Noqueados , Células TH1/inmunología , Células Th2/inmunología , Factores de Tiempo , Factor de Crecimiento Transformador beta/inmunología
16.
Opt Express ; 18(13): 13772-81, 2010 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-20588510

RESUMEN

We have shown that the application of double random phase encoding (DRPE) to biometrics enables the use of biometrics as cipher keys for binary data encryption. However, DRPE is reported to be vulnerable to known-plaintext attacks (KPAs) using a phase recovery algorithm. In this study, we investigated the vulnerability of DRPE using fingerprints as cipher keys to the KPAs. By means of computational experiments, we estimated the encryption key and restored the fingerprint image using the estimated key. Further, we propose a method for avoiding the KPA on the DRPE that employs the phase retrieval algorithm. The proposed method makes the amplitude component of the encrypted image constant in order to prevent the amplitude component of the encrypted image from being used as a clue for phase retrieval. Computational experiments showed that the proposed method not only avoids revealing the cipher key and the fingerprint but also serves as a sufficiently accurate verification system.


Asunto(s)
Algoritmos , Identificación Biométrica/métodos , Seguridad Computacional , Dermatoglifia , Óptica y Fotónica/métodos , Artefactos , Análisis de Fourier , Modelos Teóricos
17.
Heliyon ; 6(7): e04423, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32685738

RESUMEN

BACKGROUND: Evaluations for the tumorigenicity of transplantation of stem cell products is mandatory for clinical application. It is of importance to establish a system to accurately quantify contaminated tumorigenic cells regardless of the format of stem cell product. In the present report, we aimed to examine the accuracy of the quantification of tumorigenic cell numbers with commonly used 2 methods, quantitative polymerase chain reaction (qPCR) and flow cytometry (FCM) using experimental models of stem cell products spiked with tumorigenic cells. METHODS: Human mesenchymal stem cells (hMSCs) and melanoma Mewo-Luc cells constitutively expressing luciferase were used. We stained Mewo-Luc cells with a cell linker then spiked onto hMSC suspensions and hMSC sheets. We validated the accuracy of 10-fold serial dilution technique for Mewo-Luc cell suspension using a Coulter counter. The samples spiked with Mewo-Luc cells were subjected to qPCR and FCM analyses, respectively for the quantification of Mewo-Luc cells. RESULTS: Ten-fold serial dilutions of Mewo-Luc cells were performed accurately with small deviation. In samples spiked with or less than 100 cells in hMSC suspensions, and samples spiked with or less than 1,000 cells in hMSC sheets showed significantly higher cell numbers in calculations by FCM, respectively (suspensions; qPCR vs FCM: 100 cells: 59 ± 25 vs 232 ± 35 cells, p = 0.022/10 cells: 21 ± 7 vs 114 ± 27 cells, p = 0.030, sheets; qPCR vs FCM: 1,000 cells: 1723 ± 258 vs 5810 ± 878 cells, p = 0.012/100 cells: 110 ± 18 vs 973 ± 232 cells, p = 0.012/10 cells: 20 ± 6 vs 141 ± 36 cells, p = 0.030). CONCLUSION: Differences in accuracy between quantification methods should be considered in designing a tumorigenicity study model.

18.
PLoS One ; 15(11): e0241287, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33137106

RESUMEN

Currently, cardiomyocyte (CM) differentiation methods require a purification step after CM induction to ensure the high purity of the cell population. Here we show an improved human CM differentiation protocol with which high-purity ventricular-type CMs can be obtained and maintained without any CM purification process. We induced and collected a mesodermal cell population (platelet-derived growth factor receptor-α (PDGFRα)-positive cells) that can respond to CM differentiation cues, and then stimulated CM differentiation by means of Wnt inhibition. This method reproducibly generated CMs with purities above 95% in several human pluripotent stem cell lines. Furthermore, these CM populations were maintained in culture at such high purity without any further CM purification step for over 200 days. The majority of these CMs (>95%) exhibited a ventricular-like phenotype with a tendency to structural and electrophysiological maturation, including T-tubule-like structure formation and the ability to respond to QT prolongation drugs. This is a simple and valuable method to stably generate CM populations suitable for cardiac toxicology testing, disease modeling and regenerative medicine.


Asunto(s)
Diferenciación Celular/genética , Células Madre Pluripotentes Inducidas/citología , Mesodermo/crecimiento & desarrollo , Miocitos Cardíacos/citología , Técnicas de Cultivo de Célula/métodos , Linaje de la Célula/genética , Fenómenos Electrofisiológicos , Ventrículos Cardíacos/citología , Humanos , Mesodermo/citología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Proteínas Wnt/antagonistas & inhibidores
19.
Am J Case Rep ; 21: e926670, 2020 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-33035203

RESUMEN

BACKGROUND Takotsubo cardiomyopathy is characterized by apical ballooning and excessive constriction of the base of heart. However, reverse takotsubo cardiomyopathy, wherein ballooning from the mid-ventricle to the base of the heart occurs with excessive constriction of the apex, has also been reported. We report a case of a transition from atypical wall motion abnormality to a typical takotsubo cardiomyopathy pattern. CASE REPORT A 54-year-old woman was following excessive sugar and dietary restrictions because of concerns regarding her blood sugar levels while receiving treatment for diabetes at another hospital. She presented at our hospital with general malaise and chest discomfort after several days of significantly increased workload. On admission, blood tests showed elevated cardiac enzymes. Electrocardiogram showed ST elevation of V2-V3 and poor R-wave enhancement of the anterior precordial lead. Coronary angiography showed no significant stenosis; however, left ventricular (LV) angiography showed a decrease in mid-ventricular wall motion. On the basis of these findings, she was diagnosed with a reverse takotsubo cardiomyopathy. We initiated conservative treatment for her condition. During her treatment, the LV wall motion showed a typical pattern of the apical ballooning that is characteristic of takotsubo cardiomyopathy. This LV wall motion was normalized on day 22 of the onset. CONCLUSIONS We observed a rare case of takotsubo cardiomyopathy where the pattern of LV wall motion abnormality changed over time. This case suggests that it is necessary to follow up LV abnormality over time rather than rely on single-point observations in cases with takotsubo cardiomyopathy.


Asunto(s)
Cardiomiopatía de Takotsubo , Arritmias Cardíacas , Angiografía Coronaria , Ecocardiografía , Electrocardiografía , Femenino , Humanos , Persona de Mediana Edad , Cardiomiopatía de Takotsubo/diagnóstico
20.
Arterioscler Thromb Vasc Biol ; 28(6): 1068-76, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18403727

RESUMEN

OBJECTIVE: Diabetes mellitus is associated with increased oxidative stress, which induces oxidation of tetrahydrobiopterin (BH4) in vessel wall. Without enough BH4, eNOS is uncoupled to L-arginine and produces superoxide rather than NO. We examined the role of uncoupled eNOS in vascular remodeling in diabetes. METHODS AND RESULTS: Diabetes mellitus was produced by streptozotocin in C57BL/6J mice. Under stable hyperglycemia, the common carotid artery was ligated, and neointimal formation was examined 4 weeks later. In diabetic mice, the neointimal area was dramatically augmented. This augmentation was associated with increased aortic superoxide formation, reduced aortic BH4/dihydrobiopterin (BH2) ratio, and decreased plasma nitrite and nitrate (NOx) levels compared with nondiabetic mice. Chronic BH4 treatment (10 mg/kg/d) reduced the neointimal area in association with suppressed superoxide production and inflammatory changes in vessels. BH4/BH2 ratio in vessel wall was preserved, and plasma NOx levels increased. Furthermore, in the presence of diabetes, overexpression of bovine eNOS resulted in augmentation of neointimal area, accompanied by increased superoxide production in the endothelium. CONCLUSIONS: In diabetes, increased oxidative stress by uncoupled NOSs, particularly eNOS, causes augmentation of vascular remodeling. These findings indicate restoration of eNOS coupling has an atheroprotective benefit in diabetes.


Asunto(s)
Arterias Carótidas/metabolismo , Diabetes Mellitus Experimental/metabolismo , Endotelio Vascular/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Animales , Aorta/metabolismo , Biopterinas/análogos & derivados , Biopterinas/metabolismo , Biopterinas/farmacología , Arterias Carótidas/efectos de los fármacos , Arterias Carótidas/patología , Colesterol/sangre , Diabetes Mellitus Experimental/patología , Modelos Animales de Enfermedad , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/patología , GTP Ciclohidrolasa/metabolismo , Pulmón/metabolismo , Ratones , Ratones Endogámicos C57BL , Nitratos/sangre , Nitritos/sangre , Estreptozocina , Superóxidos/metabolismo
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