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When athletes in ball game sports start sprinting in the forward direction from a parallel stance, they commonly use the forward- and false-step techniques. Previous studies focusing on the performance of short-distance sprints starting in the forward direction have demonstrated that the false-step technique is superior to the forward-step technique. Although athletes start sprinting in various directions based on relevant visual cues, such as movements of the ball or the opponent players, the effectiveness of each technique for starting a sprint in the other direction is still unclear. This study aims to clarify the effectiveness of each technique in improving the performance of the short-distance sprint starting in the lateral direction. In this study, 20 athletes started 5-m sprints in the right direction from the parallel stance using either of these two techniques. Kinematic and kinetic analyses were performed from movement initiation to the flight phase after the second step in the sprinting direction. The average and terminal sprint velocities throughout this range were larger in the forward-step technique (p = 0.039 and 0.003), indicating its superiority in traveling and accelerating performance. The change of sprint velocity in the initial phase until the contact of the first step in the sprinting direction was smaller in the false-step technique (p < 0.001), although this phase included "false step." These results indicate that the forward-step technique is superior in sprints starting in the lateral direction, and the advantage results from greater acceleration in the initial phase immediately after movement initiation. These findings imply the sprint-directional dependence of the relative superiority of these techniques, providing an impetus for athletes and coaches to consider and establish the effective training and coaching methods of short-distance sprints.
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Skeletal muscle atrophy and the inhibition of muscle regeneration are known to occur as a natural consequence of aging, yet the underlying mechanisms that lead to these processes in atrophic myofibers remain largely unclear. Our research has revealed that the maintenance of proper mitochondrial-associated endoplasmic reticulum membranes (MAM) is vital for preventing skeletal muscle atrophy in microgravity environments. We discovered that the deletion of the mitochondrial fusion protein Mitofusin2 (MFN2), which serves as a tether for MAM, in human induced pluripotent stem (iPS) cells or the reduction of MAM in differentiated myotubes caused by microgravity interfered with myogenic differentiation process and an increased susceptibility to muscle atrophy, as well as the activation of the Notch signaling pathway. The atrophic phenotype of differentiated myotubes in microgravity and the regenerative capacity of Mfn2-deficient muscle stem cells in dystrophic mice were both ameliorated by treatment with the gamma-secretase inhibitor DAPT. Our findings demonstrate how the orchestration of mitochondrial morphology in differentiated myotubes and regenerating muscle stem cells plays a crucial role in regulating Notch signaling through the interaction of MAM.
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Atrofia Muscular , Ingravidez , Ratones , Humanos , Animales , Atrofia Muscular/metabolismo , Atrofia Muscular/patología , Fibras Musculares Esqueléticas/metabolismo , Transducción de Señal , Mitocondrias/metabolismo , Músculo Esquelético/metabolismoRESUMEN
Determining the degrees of freedom (DOF) of the linked rigid-body model, representing a multi-body motion of the human lower extremity, is one of the most important procedures in locomotion analysis. However, a trade-off exists between the quality of data fitting and the generalizability of the model. This study aimed to determine the optimal DOF of the model for the lower extremities that balance the goodness-of-fit and generalizability of the model during walking and running using Akaike's information criterion (AIC). Empirically obtained kinematic data for the lower extremities during walking and running were fitted by models with 9, 18, or 22 DOF. The relative quality of these models was assessed using their bias-corrected AIC (cAIC) value. A significant simple main effect of the model was found on the cAIC value for both walking and running conditions. Pairwise comparisons revealed that the cAIC value of the 18-DOF model was significantly smaller than that of the 9-DOF (walking: p < 0.001, running: p = 0.010) and 22-DOF (walking: p < 0.001, running: p < 0.001) models. These findings suggest that the 18-DOF model is optimal for representing the lower extremities during walking and running, in terms of goodness-of-fit and generalizability.
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Locomoción , Caminata , Humanos , Extremidad Inferior , Movimiento (Física) , ConvulsionesRESUMEN
BACKGROUND: Bullous pemphigoid (BP) is an autoimmune bullous disease in which abundant eosinophils accumulate in the blisters. Galectin-10 abounds in the cytoplasm of eosinophils and is released as a result of eosinophil extracellular trap cell death (EETosis). OBJECTIVE: To identify EETosis and the pathological roles of galectin-10 in BP. METHODS: EETosis and galectin-10 in BP blisters were confirmed by immunofluorescence and transmission electron microscopy. The concentrations of galectin-10 in serum and blister fluid from BP patients were studied by ELISA. The matrix metalloproteinase (MMP) expression in BP blisters was immunohistochemically compared to that in healthy controls. As an in vitro assay, normal human epidermal keratinocytes (NHEKs) and normal human dermal fibroblasts (NHDFs) were stimulated with galectin-10, followed by MMP expression measurement by real-time PCR and ELISA. The signaling pathways activated by galectin-10 were studied using Western blotting and confirmed by inhibition assays. RESULTS: Galectin-10-containing eosinophil infiltration and the extracellular deposition of major basic protein were observed in BP blisters. The ultrastructural characteristics of tissue eosinophils indicated piecemeal degranulation and EETosis. In the BP patients, the concentration of galectin-10 was higher in the blister fluid than in the serum. Several types of MMPs were upregulated in BP blisters. Galectin-10 upregulated the production of MMPs through the pathways of p38 MAPK, ERK and JNK in NHEKs and NHDFs. CONCLUSION: In the BP blisters, the eosinophils underwent EETosis and released galectin-10. Galectin-10 might contribute to BP blister formation through the production of MMPs by keratinocytes and fibroblasts.
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Vesícula , Penfigoide Ampolloso , Humanos , Vesícula/patología , Eosinófilos , Metaloproteinasas de la Matriz , GalectinasRESUMEN
Autologous hematopoietic stem cell transplantation (SCT) is not a standard treatment option for Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL); however, its position has been reassessed since the introduction of tyrosine kinase inhibitors (TKIs). We prospectively analyzed the efficacy and safety of autologous peripheral blood SCT (auto-PBSCT) for Ph+ALL patients aged between 55 and 70 years who had achieved complete molecular remission. Melphalan, cyclophosphamide, etoposide, and dexamethasone were used for conditioning. A total of 12 courses of maintenance therapy, including dasatinib, were performed. The required number of CD34+ cells was harvested in all five patients. No patient died within 100 days after auto-PBSCT, and no unexpected serious adverse events were observed. Although 1-year event-free survival was 100%, hematological relapse was observed in three patients at a median of 801 days (range, 389-1088 days) after auto-PBSCT. Molecular progressive disease was observed in the other two patients, although they maintained their first hematological remission at the last visit. Auto-PBSCT can be safely performed for Ph+ALL with TKIs. A limitation of auto-PBSCT was suggested, despite the increase in the intensity of a single treatment. The development of long-term therapeutic strategies by including new molecular targeted drugs is warranted to maintain long-term molecular remission.
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Skeletal muscle stem cells (MuSCs) have been proposed as suitable candidates for cell therapy to muscular disorders since they exhibit a good capacity for myogenic regeneration. However, for better therapeutic outcomes, it is necessary to isolate human MuSCs from a suitable tissue source that possess high myogenic differentiation. In this context, isolated CD56+CD82+ cells from extra eyelid tissues were tested in vitro myogenic differentiation potential. Primary human myogenic cells derived from extra eyelids including orbicularis oculi, might be good candidates for human muscle stem cell-based research.
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Párpados , Fibras Musculares Esqueléticas , Humanos , Diferenciación Celular , Células Madre , Músculo Esquelético/fisiologíaRESUMEN
The foot and trunk kinematics could be associated with horizontal velocity during underwater undulatory swimming (UUS). This study aimed to compare the foot and trunk kinematic parameters during UUS between faster and slower swimmers. The three-dimensional coordinates of the markers were collected during 15 m UUS for 13 swimmers. Participants were divided into two groups based on their horizontal UUS velocity. The range of motion of the lower waist was greater for the faster swimmers than for the slower swimmers; however, no group differences were found for the foot orientation angle. Both the maximum flexion and extension angular velocities of the lower waist and maximum extension angular velocity of the chest were greater for faster swimmers than for slower swimmers. The toe vertical velocity during upward and downward kicks and horizontal displacement per kick were greater for the faster swimmers than for the slower swimmers, whereas no group difference was found for kick frequency. The increase in the long horizontal displacement per kick could be explained by the increase in vertical velocity of the great toes due to the increased trunk angular velocity. These results indicate that faster swimmers performed the UUS with greater trunk angular velocity.
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Extremidad Inferior , Natación , Fenómenos Biomecánicos , Pie , Humanos , Rango del Movimiento ArticularRESUMEN
The significance of antibody-identified epitopes stimulating humoral alloimmunity is not well understood in the identification of non-permissive human leukocyte antigen (HLA) mismatching patterns in hematopoietic stem cell transplantation (HSCT). This was a retrospective study in a cohort of 9,991 patients who underwent their first HSCT for hematologic malignancies from unrelated bone marrow donors in the Transplant Registry Unified Management Program (TRUMP). HLA eplet mismatches (EMM) were quantified using HLAMatchmaker (HLAMM). The median age of patients was 48 years (range, 16 to 77). The number of EMM in recipient-donor pairs in our study population ranged from 0 to 37 in HLA class I (median, 0) and 0 to 60 in HLA class II (median, 1). In addition to the known high-risk mismatch patterns in the Japanese cohort, HLA-C EMM in the GVH direction was associated with a significantly higher risk for grade III-IV aGVHD, leading to a higher risk of non-relapse mortality and lower overall survival (compared with HLA-C matched patients, HR 1.67, 95% CI 1.44-1.95; HR 1.39, 95% CI 1.25-1.54; HR 1.20, 95% CI 1.10-1.30, respectively). HLAMM-based epitope matching might be useful for identifying patients who are at high risk for serious complications after HSCT from HLA mismatched unrelated donors.
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Trasplante de Médula Ósea , Antígenos HLA-C , Adolescente , Adulto , Anciano , Trasplante de Médula Ósea/efectos adversos , Epítopos , Antígenos HLA/genética , Prueba de Histocompatibilidad , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Adulto JovenRESUMEN
The proliferation and differentiation of skeletal muscle cells are usually controlled by serum components. Myogenic differentiation is induced by a reduction of serum components in vitro. It has been recently reported that serum contains not only various growth factors with specific actions on the proliferation and differentiation of myogenic cells, but also exogenous exosomes, the function of which is poorly understood in myogenesis. We have found that exosomes in fetal bovine serum are capable of exerting an inhibitive effect on the differentiation of C2C12 myogenic cells in vitro. In this process of inhibition, the downregulation of Tceal5 and Tceal7 genes was observed. Expression of these genes is specifically increased in direct proportion to myogenic differentiation. Loss- or gain- of function studies with Tceal5 and Tceal7 indicated that they have the potential to regulate myogenic differentiation via exosomes in fetal bovine serum.
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Diferenciación Celular , Mioblastos , Factores de Transcripción , Animales , Ratones , Línea Celular , Exosomas/metabolismo , Mioblastos/citología , Mioblastos/efectos de los fármacos , Mioblastos/metabolismo , Albúmina Sérica Bovina/farmacología , Factores de Transcripción/genética , Factores de Transcripción/metabolismoAsunto(s)
Melanoma , Neoplasias Cutáneas , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bencimidazoles , Carbamatos , Humanos , Imidazoles , Lactato Deshidrogenasas , Melanoma/tratamiento farmacológico , Mutación , Oximas , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas B-raf/genética , Piridonas , Pirimidinonas , Neoplasias Cutáneas/tratamiento farmacológico , SulfonamidasRESUMEN
PURPOSE: To characterize the issues regarding work and employment specific to allogeneic hematopoietic cell transplantation (allo-HCT) survivors, we conducted a nationwide cross-sectional questionnaire survey. METHODS: We targeted allo-HCT survivors employed at diagnosis, aged 20-64 at survey, and survived ≥2 years without relapse. The questionnaire included the timing of and reasons for resignation (termination of employment contract), and patient-related, HCT-related, work-related, and HCT center-related factors. RESULTS: A total of 1048 eligible participants were included in the analysis (response rate, 60%). The median time after allo-HCT was 5 years (range, 2-30) at the time of survey. After diagnosis, 41% of participants resigned from work throughout the course of treatment. The most frequent timing of the first resignation was "after discharge post-HCT" (46%), followed by "from diagnosis to initial treatment" (27%). Factors significantly associated with resignation included female gender, older age, and part-time employment. Favorable factors included the presence of occupational health staff at the workplace, employment of ≥10 years, and self-employed/freelance. After resignation, the overall incidence of return to work with some accommodations was 76% at 5 years after HCT, but it was 52% without any accommodation. CONCLUSIONS: Overall, the rate of resignation was 41%, and the most frequent timing of resignation was after discharge post-HCT, accounting for approximately half of the resignations (46%). Workplace accommodations increased the rate of return to work from 52% to 76%. IMPLICATIONS FOR CANCER SURVIVORS: Early detection of employment-related concerns and support throughout the treatment process are necessary for patients receiving allo-HCT.
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Trasplante de Células Madre Hematopoyéticas , Reinserción al Trabajo , Estudios Transversales , Empleo , Femenino , Humanos , SobrevivientesRESUMEN
A 47-year-old woman presented with progressive limb weakness. A neurological examination revealed proximal dominant symmetrical muscle weakness in her limbs, and electromyography revealed complex repetitive discharges and short motor unit potentials with positive sharp waves in the biceps. We observed early recruitment in the quadriceps, and laboratory tests revealed normal creatine kinase. Serum protein electrophoresis showed monoclonal IgG-lambda, but the bone marrow aspiration specimen was normal. A muscle biopsy revealed nemaline rod accumulations in the muscle fibers; based on the results, we diagnosed the patient with sporadic late-onset nemaline myopathy with monoclonal gammopathy of undetermined significance (SLONM-MGUS). We administered repeated intravenous immunoglobulin, but her limb weakness continued, and she developed a restrictive ventilatory defect. The patient received melphalan, followed by autologous stem-cell transplantation (ASCT). Her upper extremity strength and respiratory capability improved within one year after ASCT; however, it was not until six years after ASCT that her atrophied lower extremities strengthened. A discrepancy in the timeline of treatment response between the upper or respiratory muscles and the atrophied lower limb was characteristic in the patient, suggesting that the efficacy of ASCT on SLONM-MGUS should be evaluated in the long term, especially in severely atrophied muscles. In addition, this case showed that ASCT for SLOMN-MGUS is an effective treatment option in Asian populations.
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Trasplante de Células Madre Hematopoyéticas , Gammopatía Monoclonal de Relevancia Indeterminada , Miopatías Nemalínicas , Femenino , Humanos , Persona de Mediana Edad , Músculo Esquelético , Resultado del TratamientoRESUMEN
BACKGROUND: Mesenchymal stromal cells (MSCs) function as supportive cells on skeletal muscle homeostasis through several secretory factors including type 6 collagen (COL6). Several mutations of COL6A1, 2, and 3 genes cause Ullrich congenital muscular dystrophy (UCMD). Skeletal muscle regeneration deficiency has been reported as a characteristic phenotype in muscle biopsy samples of human UCMD patients and UCMD model mice. However, little is known about the COL6-dependent mechanism for the occurrence and progression of the deficiency. The purpose of this study was to clarify the pathological mechanism of UCMD by supplementing COL6 through cell transplantation. METHODS: To test whether COL6 supplementation has a therapeutic effect for UCMD, in vivo and in vitro experiments were conducted using four types of MSCs: (1) healthy donors derived-primary MSCs (pMSCs), (2) MSCs derived from healthy donor induced pluripotent stem cell (iMSCs), (3) COL6-knockout iMSCs (COL6KO-iMSCs), and (4) UCMD patient-derived iMSCs (UCMD-iMSCs). RESULTS: All four MSC types could engraft for at least 12 weeks when transplanted into the tibialis anterior muscles of immunodeficient UCMD model (Col6a1KO) mice. COL6 protein was restored by the MSC transplantation if the MSCs were not COL6-deficient (types 1 and 2). Moreover, muscle regeneration and maturation in Col6a1KO mice were promoted with the transplantation of the COL6-producing MSCs only in the region supplemented with COL6. Skeletal muscle satellite cells derived from UCMD model mice (Col6a1KO-MuSCs) co-cultured with type 1 or 2 MSCs showed improved proliferation, differentiation, and maturation, whereas those co-cultured with type 3 or 4 MSCs did not. CONCLUSIONS: These findings indicate that COL6 supplementation improves muscle regeneration and maturation in UCMD model mice.
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Colágeno Tipo VI , Músculo Esquelético , Animales , Trasplante de Células , Colágeno Tipo VI/genética , Suplementos Dietéticos , Humanos , Ratones , Distrofias Musculares , EsclerosisRESUMEN
Infection is one of the major causes of death in hematopoietic stem cell transplantation (HSCT) survivors. Precise assessments of immune function after HSCT will be critical in establishing appropriate treatment and prophylaxis, such as re-vaccination. Although several surrogate markers for prediction of clinical outcomes after HSCT have been proposed, definitive markers of immune reconstitution and data on those markers in long-term survivors are lacking. In this study, cellular response to mitogens was assessed and clinical features associated with a poor response to mitogens were investigated in long-term allogeneic HSCT survivors. Age at transplantation and age at the time of mitogen stimulation test were each identified as significant risk factors for poor response to phytohemagglutinin and concanavalin A, respectively (P < 0.001 each). However, time elapsed since transplantation was not found to be correlated with responsiveness to mitogens in this study. Prospective, in-depth studies on immune reconstitution are needed to establish appropriate prophylaxis against infections after HSCT and a schedule for re-vaccination.
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Inmunidad Celular , Mitógenos/inmunología , Enfermedad Injerto contra Huésped/diagnóstico , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas , Humanos , Recuento de Leucocitos , Activación de Linfocitos/inmunología , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Sobrevivientes , Inmunología del Trasplante , Trasplante HomólogoRESUMEN
Adult T cell leukemia/lymphoma (ATL) is a highly aggressive hematologic malignancy with a very poor prognosis, and most patients with ATL are elderly. Although post-transplantation cyclophosphamide (PTCy) has yielded promising results in various diseases, available data are limited regarding its outcomes in ATL. The aim of this study was to determine the safety and efficacy of reduced-intensity peripheral blood stem cell transplantation (PBSCT) from a human leukocyte antigen (HLA)-haploidentical donor using PTCy as graft-versus-host disease (GVHD) prophylaxis. This was a prospective, multicenter phase I/II study (UMIN000021783) conducted at 16 hospitals in Japan. The primary endpoint was the probability of survival with engraftment and without grade III/IV acute GVHD at day 60 after PBSCT. The expected probability of the primary endpoint was estimated to be 60%, and the threshold probability was set at 30% on the basis of previous studies. The conditioning regimen consisted of fludarabine (30 mg/m2/d from day -7 to -2), melphalan (40 mg/m2/d on days -3 and -2), and total body irradiation (2 Gy on day -1). GVHD prophylaxis consisted of tacrolimus starting at 0.02 mg/kg/d on day -1, PTCy (50 mg/kg/d on days +3 and +5), and mycophenolate mofetil 2000 mg/d starting on day +6. Eighteen ATL patients underwent PBSCT. The probability of patients who met the primary endpoint was 89% (95% confidence interval, 65% to 99%). The cumulative incidences of grade II to IV acute GVHD, III/IV acute GVHD, and moderate-to-severe chronic GVHD were 39%, 11%, and 17%, respectively. The probabilities of overall survival were 83% at 1 year and 73% at 2 years. The cumulative incidences of non-relapse mortality and disease progression at 1 year were 11% and 28%, respectively. HLA-haploidentical PBSCT with PTCy as GVHD prophylaxis is a valid option for patients with aggressive ATL.
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Trasplante de Células Madre Hematopoyéticas , Leucemia-Linfoma de Células T del Adulto , Linfoma , Trasplante de Células Madre de Sangre Periférica , Anciano , Ciclofosfamida/uso terapéutico , Antígenos HLA , Humanos , Leucemia-Linfoma de Células T del Adulto/terapia , Estudios ProspectivosRESUMEN
From standing in a parallel stance, two common techniques for sprint starts are forward and false steps. In the forward step technique, athletes take a first step in the sprinting direction; in the false step technique, the first step is in the opposite direction to the sprinting direction. Although the false step technique, including a redundant step, has generally been considered as an inferior technique, athletes habitually use it to start sprinting in a forward direction. The present study aimed to clarify which step technique is habitually used by high-level male soccer players when they start sprinting in a backward or a sideward direction. From a stationary standing position, 15 male soccer players were instructed to sprint backward and rightward three times each, and the step techniques used to start sprinting were recorded. In the backward sprint start trials, 2 trials were done using the forward step technique and 43 using the false step technique. In the rightward sprint start trials, 27 trials were done using the forward step technique and 18 using the false step technique. While the false step technique was used significantly more than the forward step technique in the backward sprint start trials (p < 0.001), no significant difference was found between the use of either technique in the rightward sprint start trials (p = 0.18). The results demonstrate that high-level male soccer players habitually use the false step technique in a backward sprint start and use both techniques with similar frequencies in a sideward sprint start.
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Regulatory T (Treg) cells, which are essential for maintaining self-tolerance, inhibit anti-tumor immunity, consequently hindering protective cancer immunosurveillance, and hampering effective anti-tumor immune responses in tumor-bearing hosts. Here, we show that depletion of Treg cells via targeting glycoprotein A repetitions predominant (GARP) induces effective anti-tumor immune responses. GARP was specifically expressed by highly suppressive Treg cells in the tumor microenvironment (TME) of multiple cancer types in humans. In the periphery, GARP was selectively induced in Treg cells, but not in effector T cells, by polyclonal stimulation. DS-1055a, a novel afucosylated anti-human GARP monoclonal antibody, efficiently depleted GARP+ Treg cells, leading to the activation of effector T cells. Moreover, DS-1055a decreased FoxP3+CD4+ T cells in the TME and exhibited remarkable anti-tumor activity in humanized mice bearing HT-29 tumors. We propose that DS-1055a is a new Treg-cell-targeted cancer immunotherapy agent with augmentation of anti-tumor immunity.
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Anticuerpos Monoclonales/inmunología , Proteínas de la Membrana/inmunología , Neoplasias/inmunología , Linfocitos T Reguladores/inmunología , Animales , Femenino , Humanos , Tolerancia Inmunológica/inmunología , Inmunidad/inmunología , Inmunoterapia/métodos , Leucocitos Mononucleares/inmunología , Ratones , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Microambiente Tumoral/inmunologíaAsunto(s)
Síndrome de Hipersensibilidad a Medicamentos , Eosinofilia , Preparaciones Farmacéuticas , Síndrome de Hipersensibilidad a Medicamentos/diagnóstico , Síndrome de Hipersensibilidad a Medicamentos/etiología , Síndrome de Hipersensibilidad a Medicamentos/terapia , Eosinofilia/inducido químicamente , Eosinofilia/diagnóstico , Humanos , Lenalidomida/efectos adversosRESUMEN
A 37-year-old man diagnosed with diffuse large B-cell lymphoma two weeks previously, visited our emergency department with sudden dyspnea. He had a severe respiratory failure with saturated percutaneous oxygen at 80% (room air). Chest radiography showed a large amount of left pleural effusion. After 1000 mL of the effusion was urgently drained, reexpansion pulmonary edema (RPE) occurred. Despite ventilator management, oxygenation did not improve and venovenous extracorporeal membrane oxygenation (VV-ECMO) was initiated in the intensive care unit. The next day, contrast-enhanced computed tomography showed a massive thrombus in the right pulmonary artery, at this point the presence of pulmonary thromboembolism (PTE) was revealed. Fortunately, the patient's condition gradually improved with anticoagulant therapy and VV-ECMO support. VV-ECMO was successfully discontinued on day 4, and chemotherapy was initiated on day 8. We speculated the following mechanism in this case: blood flow to the right lung significantly reduced due to acute massive PTE, and blood flow to the left lung correspondingly increased, which could have caused RPE in the left lung. Therefore, our observations suggest that drainage of pleural effusion when contralateral blood flow is impaired due to acute PTE may increase the risk of RPE.
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Duchenne muscular dystrophy (DMD) is a progressive and fatal muscle-wasting disease caused by DYSTROPHIN deficiency. Cell therapy using muscle stem cells (MuSCs) is a potential cure. Here, we report a differentiation method to generate fetal MuSCs from human induced pluripotent stem cells (iPSCs) by monitoring MYF5 expression. Gene expression profiling indicated that MYF5-positive cells in the late stage of differentiation have fetal MuSC characteristics, while MYF5-positive cells in the early stage of differentiation have early myogenic progenitor characteristics. Moreover, late-stage MYF5-positive cells demonstrated good muscle regeneration potential and produced DYSTROPHIN in vivo after transplantation into DMD model mice, resulting in muscle function recovery. The engrafted cells also generated PAX7-positive MuSC-like cells under the basal lamina of DYSTROPHIN-positive fibers. These findings suggest that MYF5-positive fetal MuSCs induced in the late stage of iPSC differentiation have cell therapy potential for DMD.