135 research outputs found

    Determinacion del Efecto Citotoxico del Extracto de Hojas de Annona Muricata l. (Guanábana) en Cultivo de Líneas Celulares de Cáncer de Prostata (pc-3) y Cáncer de Páncreas (ASPC-1)

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    El cáncer es una de las causas de muerte más importante a nivel mundial, dentro de ellas el cáncer de próstata y el cáncer de páncreas cuya principal diferencia es que el primero es de tipo localizado y desarrollo lento y el segundo es de tipo metástasico y desarrollo rápido; en ambos tipos se ha observado un incremento en la resistencia a las quimioterapias lo cual motiva la búsqueda de nuevas alternativas de tratamiento. Desde tiempos remotos el uso de plantas ha demostrado efectividad frente a ciertas enfermedades, en la actualidad muchos estudios previos han sugerido que la Annona muricata L. (Guanábana) posee una actividad citotóxica frente a células cancerígenas, esto genera gran interés en el desarrollo de posibles alternativas de tratamiento para el cáncer. Dado que es un tratamiento de origen vegetal se debe determinar el solvente adecuado para extraer la mayor cantidad de sus componentes que le confieren sus propiedades, determinar la concentración y tiempo de exposición óptimo al extracto a utilizar para producir el efecto deseado. La reducción de la viabilidad celular es apoyada por la estadística de significancia, el cual indico una diferencia significativa en la viabilidad entre el control y los grupos de tratamiento (p<0.05). La presente investigación se desarrolló teniendo como objetivo principal la evaluación del efecto citotóxico del extracto de hojas de Annona muricata L. (Guanábana) sobre las líneas celulares de cáncer de páncreas (ASPC-1) y cáncer de próstata (PC-3).Para lograr dicho fin se utilizó hojas de Guanábana las cuales fueron previamente recolectadas en Costa Rica y secadas en sombra; estas fueron molidas para su utilización; luego se procedió a realizar una extracción por maceración utilizando como solvente metanol 90%. Posteriormente se realizaron re-extracciones del primer extracto utilizando 3 solventes adicionales (diclorometano, acetato de etilo, n-butanol), obteniéndose finalmente 5 extractos diferentes: metanol 90% (extracto crudo), diclorometano, acetato de etilo, n-butanol, acuoso (residual); y se procedió a evaluar el rendimiento obtenido de cada re-extracto. Los extractos fueron empleados para evaluar la viabilidad de las líneas celulares ASPC-1 y PC-3 tras ser expuestas a los 5 extractos obtenidos; por 24 y 48 horas de exposición al tratamiento en las siguientes concentraciones 1µg/mL, 3µg/mL, 10µg/mL, 30µg/mL y 100µg/mL. Para poder determinar los efectos de los extractos de hojas de Annona muricata L. sobre la viabilidad celular, se utilizó el ensayo de proliferación celular MTS. También se evaluó si el extracto de hojas de Annona muricata L. puede ser el causante del proceso de activación de las caspasas, lo cual como consecuencia promueve una sucesión de eventos intracelulares que finalmente produce la destrucción controlada de los componentes celulares. El kit de ensayo CaspaseGlo®-3/7 luminescence fue utilizado para determinar y cuantificar el grado y/o nivel de destrucción celular. Paralelamente se midió el nivel de Lactato Deshidrogenasa (LDH) liberada; dado que es una enzima altamente estable la cual es útil para determinar el daño celular a nivel de la membrana.´ PALABRAS CLAVE: Cáncer, Guanábana, Célula

    Epstein-Barr Virus-Positive Mucocutaneous Ulcer: A Unique and Curious Disease Entity

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    Epstein-Barr virus (EBV)-positive mucocutaneous ulcer (EBVMCU) was first described as a lymphoproliferative disorder in 2010. EBVMCU is a unifocal mucosal or cutaneous ulcer that often occurs after local trauma in patients with immunosuppression; the patients generally have a good prognosis. It is histologically characterized by proliferating EBV-positive atypical B cells accompanied by ulcers. On the basis of conventional pathologic criteria, EBVMCU may be misdiagnosed as EBV-positive diffuse large B-cell lymphoma or other lymphomas. However, its prognosis differs from that of EBV-associated lymphomas, in that patients with EBVMCU frequently show spontaneous regression or complete remission without chemotherapy. Therefore, EBVMCU is now recognized as a low-grade malignancy or a pseudo-malignant lesion. Avoiding unnecessary chemotherapy by distinguishing EBVMCU from other EBV-associated lymphomas will reduce the burden and unnecessary harm on patients. On the basis of these facts, EBVMCU was first described as a new clinicopathological entity by the World Health Organization in 2017. In this review, we discuss the clinicopathological characteristics of previously reported EBVMCU cases, while focusing on up-to-date clinical, pathological, and genetic aspects

    Surgical removal of amyloid-laden lymph nodes: a possible therapeutic approach in a primary systemic AL amyloidosis patient with focal lymphadenopathy

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    We report a patient with primary systemic AL amyloidosis who suffered from remarkable bilateral cervical lymphadenopathy. Intensive chemotherapies, including two cycles of high-dose melphalan with autologous peripheral blood stem cell transplantation, were insufficiently effective for both the lymphadenopathy and amyloidogenic IgG lambda lambda-type M-protein in serum, but the patient showed complete haematological remission after extensive surgical removal of enlarged lymph nodes that had massive depositions of lambda lambda-type immunoglobulin light chain-derived amyloid. Lymphadenectomy may be a possible therapeutic approach with regard to both cosmetic and haematological aspects in primary systemic AL amyloidosis patients with focal lymphadenopathy.ArticleAMYLOID-JOURNAL OF PROTEIN FOLDING DISORDERS. 18(2):79-82 (2011)journal articl

    Upregulated Expression of Activation-Induced Cytidine Deaminase in Ocular Adnexal Marginal Zone Lymphoma with IgG4-Positive Cells

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    Immunoglobulin G4-related disease (IgG4-RD) is a systemic disorder characterized by tissue fibrosis and intense lymphoplasmacytic infiltration, causing progressive organ dysfunction. Activation-induced cytidine deaminase (AID), a deaminase normally expressed in activated B-cells in germinal centers, edits ribonucleotides to induce somatic hypermutation and class switching of immunoglobulin. While AID expression is strictly controlled under physiological conditions, chronic inflammation has been noted to induce its upregulation to propel oncogenesis. We examined AID expression in IgG4-related ophthalmic disease (IgG4-ROD; n = 16), marginal zone lymphoma with IgG4-positive cells (IgG4+ MZL; n = 11), and marginal zone lymphoma without IgG4-positive cells (IgG4- MZL; n = 12) of ocular adnexa using immunohistochemical staining. Immunohistochemistry revealed significantly higher AID-intensity index in IgG4-ROD and IgG4+ MZL than IgG4- MZL (p < 0.001 and = 0.001, respectively). The present results suggest that IgG4-RD has several specific causes of AID up-regulation in addition to inflammation, and AID may be a driver of oncogenesis in IgG4-ROD to IgG4+ MZL

    Regulation of membrane phospholipid biosynthesis in mammalian cells.

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    In mammalian cells, phospholipids and cholesterol are assembled into bilayer membranes forming the plasma membrane, nuclear envelope, mitochondria, endoplasmic reticulum, Golgi apparatus, lysosomes, and endosomes. Phospholipids are divided into classes based on the molecular structures, including phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidic acid, phosphatidylinositol, phosphatidylglycerol, cardiolipin, and sphingomyelin. In addition to their structural roles, phospholipids play important roles in many cellular processes, such as membrane protein regulation, membrane trafficking, cell growth, apoptosis, and intracellular signaling. Thus, abnormal phospholipid metabolism is associated with various diseases. In mammalian cells, phospholipid classes are generated through several enzymatic steps, predominantly in the endoplasmic reticulum, mitochondria, and Golgi apparatus. In recent years, various enzymes involved in the biosynthesis of phospholipid classes have been identified. However, little is known about the regulatory mechanisms underlying the biosynthesis of phospholipid classes. Using our recently developed enzymatic fluorometric assays for all major phospholipid classes, we have demonstrated changes in phospholipid composition in intracellular organelles during cell growth. In this review, we summarize the current understanding of the properties and functions of phospholipid biosynthesis enzymes, and discuss their regulatory mechanisms

    New Panoramic View of 12^{12}CO and 1.1 mm Continuum Emission in the Orion A Molecular Cloud. I. Survey Overview and Possible External Triggers of Star Formation

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    We present new, wide and deep images in the 1.1 mm continuum and the 12^{12}CO (JJ=1-0) emission toward the northern part of the Orion A Giant Molecular Cloud (Orion-A GMC). The 1.1 mm data were taken with the AzTEC camera mounted on the Atacama Submillimeter Telescope Experiment (ASTE) 10 m telescope in Chile, and the 12^{12}CO (JJ=1-0) data were with the 25 beam receiver (BEARS) on the NRO 45 m telescope in the On-The-Fly (OTF) mode. The present AzTEC observations are the widest (\timeform{1.D7} ×\times \timeform{2.D3}, corresponding to 12 pc ×\times 17 pc) and the highest-sensitivity (\sim9 mJy beam1^{-1}) 1.1 mm dust-continuum imaging of the Orion-A GMC with an effective spatial resolution of \sim 40\arcsec. The 12^{12}CO (JJ=1-0) image was taken over the northern \timeform{1D.2} \times\timeform{1D.2} (corresponding 9 pc ×\times 9 pc) area with a sensitivity of 0.93 K in TMBT_{\rm MB}, a velocity resolution of 1.0 km s1^{-1}, and an effective spatial resolution of 21\arcsec. With these data, together with the MSX 8 μ\mum, Spitzer 24 μ\mum and the 2MASS data, we have investigated the detailed structure and kinematics of molecular gas associated with the Orion-A GMC and have found evidence for interactions between molecular clouds and the external forces that may trigger star formation. Two types of possible triggers were revealed; 1) Collision of the diffuse gas on the cloud surface, particularly at the eastern side of the OMC-2/3 region, and 2) Irradiation of UV on the pre-existing filaments and dense molecular cloud cores. Our wide-field and high-sensitivity imaging have provided the first comprehensive view of the potential sites of triggered star formation in the Orion-A GMC.Comment: 32 pages, 20 figures, accepted for publication in PAS

    Rho-associated protein kinase and cyclophilin a are involved in inorganic phosphate-induced calcification signaling in vascular smooth muscle cells

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    Arterial calcification, a risk factor of cardiovascular events, develops with differentiation of vascular smooth muscle cells (VSMCs) into osteoblast-like cells. Cyclophilin A (CypA) is a peptidyl-prolyl isomerase involved in cardiovascular diseases such as atherosclerosis and aortic aneurysms, and rho-associated protein kinase (ROCK) is involved in the pathogenesis of vascular calcification. CypA is secreted in a ROCK activity-dependent manner and works as a mitogen via autocrine or paracrine mechanisms in VSMCs. We examined the involvement of the ROCK-CypA axis in VSMC calcification induced by inorganic phosphate (Pi), a potent cell mineralization initiator. We found that Pi stimulated ROCK activity, CypA secretion, extracellular signal-regulated protein kinase (ERK) 1/2 phosphorylation, and runt-related transcription factor 2 expression, resulting in calcium accumulation in rat aortic smooth muscle cells (RASMCs). The ROCK inhibitor Y-27632 significantly suppressed Pi-induced CypA secretion, ERK1/2 phosphorylation, and calcium accumulation. Recombinant CypA was found to be associated with increased calcium accumulation in RASMCs. Based on these results, we suggest that autocrine CypA is mediated by ROCK activity and is involved in Pi-induced ERK1/2 phosphorylation following calcification signaling in RASMCs

    PD-L1 expression is associated with the spontaneous regression of patients with methotrexate-associated lymphoproliferative disorders

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    Background Most patients with methotrexate-associated lymphoproliferative disorder (MTX-LPD) show diffuse large B-cell lymphoma (DLBCL) or classic Hodgkin lymphoma (CHL) types. Patients with MTX-LPD often have spontaneous remission after MTX discontinuation, but chemotherapeutic intervention is frequently required in patients with CHL-type MTX-LPD. In this study, we examined whether programmed cell death-ligand 1 (PD-L1) expression levels were associated with the prognosis of MTX-LPD after MTX discontinuation. Methods A total of 72 Japanese patients diagnosed with MTX-LPD were clinicopathologically analyzed, and immunohistochemical staining of PD-L1 was performed in 20 DLBCL-type and 24 CHL-type MTX-LPD cases to compare with the clinical course. Results PD-L1 was expressed in 5.0% (1/20) of patients with DLBCL-type MTX-LPD, whereas it was expressed in 66.7% (16/24) of the patients with CHL-type MTX-LPD in more than 51% of tumor cells. Most CHL-type MTX-LPD patients with high PD-L1 expression required chemotherapy owing to exacerbations or relapses after MTX discontinuation. However, no significant differences in clinicopathologic findings at diagnosis were observed between PD-L1 high- and low-expression CHL-type MTX-LPD. Conclusion PD-L1 expression was significantly higher in patients with CHL-type than DLBCL-type MTX-LPD, suggesting the need for chemotherapy in addition to MTX discontinuation in CHL-type MTX-LPD patients to achieve complete remission. No association was observed between PD-L1 expression levels and clinical findings at diagnosis, suggesting that PD-L1 expression in tumor cells influences the pathogenesis of CHL-type MTX-LPD after MTX discontinuation

    Detection of Strong Millimeter Emission from the Circumstellar Dust Disk Around V1094 Sco: Cold and Massive Disk around a T Tauri Star in a Quiescent Accretion Phase?

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    We present the discovery of a cold massive dust disk around the T Tauri star V1094 Sco in the Lupus molecular cloud from the 1.1 millimeter continuum observations with AzTEC on ASTE. A compact (rr\lesssim320 AU) continuum emission coincides with the stellar position having a flux density of 272 mJy which is largest among T Tauri stars in Lupus. We also present the detection of molecular gas associated with the star in the five-point observations in 12^{12}CO J=3--2 and 13^{13}CO J=3--2. Since our 12^{12}CO and 13^{13}CO observations did not show any signature of a large-scale outflow or a massive envelope, the compact dust emission is likely to come from a disk around the star. The observed SED of V1094 Sco shows no distinct turnover from near infrared to millimeter wavelengths, which can be well described by a flattened disk for the dust component, and no clear dip feature around 10 \micron suggestive of absence of an inner hole in the disk. We fit a simple power-law disk model to the observed SED. The estimated disk mass ranges from 0.03 to \gtrsim0.12 M_\sun, which is one or two orders of magnitude larger than the median disk mass of T Tauri stars in Taurus.Comment: 18 pages, 4 figures, accepted for publication in Ap

    Significant Impact of Age on Mortality and Non-significant Impact of Age on Thrombosis and Major Bleeding in Patients with COVID-19: From the CLOT-COVID Study.

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    AIM: There is scarce data on the impact of age on clinical outcomes in patients with coronavirus disease 2019 (COVID-19). METHOD: The CLOT-COVID Study was a retrospective, multicenter cohort study enrolling 2894 consecutive hospitalized patients with COVID-19 among 16 centers in Japan from April 2021 to September 2021. We divided the entire cohort into five groups according to age strata; -19, 20-39, 40-59, 60-79, and 80- years. RESULTS: Most patients under 19 had mild COVID-19 on admission (99%), while older patients had more severe COVID-19. The incidence rates of clinical outcomes during hospitalization in patients aged ≤ 19, 20-39, 40-59, 60-79, and 80 ≥ years were 0.0%, 0.5%, 2.2%, 2.7%, and 1.5% for thrombosis; 0.0%, 1.2%, 1.5%, 3.4%, and 2.0% for major bleeding; and 0.0%, 0.4%, 2.0%, 12.1%, and 16.8% for all-cause death, respectively. In the stratified analysis according to COVID-19 severity on admission, the incidences of thrombosis were generally higher among patients with more severe status, although those were not significantly different among age strata in all sub-types of COVID-19 severity. However, the incidences of all-cause death were significantly higher with increasing age in all sub-types of COVID-19 severity. CONCLUSIONS: In the current large observational study of patients with COVID-19, the risk of mortality became markedly higher with increased age. However, the risks of thrombosis and major bleeding did not necessarily increase as age increases, which seemed to be consistent irrespective of COVID-19 severity on admission
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