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1.
Yakugaku Zasshi ; 143(7): 607-616, 2023 Jul 01.
Artículo en Japonés | MEDLINE | ID: mdl-37225498

RESUMEN

In today's world, where clinical options are ever increasing and patients' needs are more diverse, it is not possible to conclude that simply practicing medical care based on pathophysiological data and medical evidence is sufficient for patients, particularly in terms of seeing each patient as an individual. Medical professionals must maintain a close relationship with their patients and seek treatment and care methods that reflect the patient's values and views on life and death, based on their own ethics in medical care. Ethics education should be provided on a continuing basis from the beginning of medical/pharmacy school. However, ethics education in pharmacy departments is often delivered in a lecture format attended by many students and/or as group training using case studies and hypothetical situations, i.e., "paper" patients. With these teaching methods, there are limited opportunities for the students to foster a sense of ethics or to think deeply about their values and views on life and death with respect to the patients they care for. Therefore, in this study, we conducted ethics exercises for pharmacy students in a group study format using a documentary film of real patients who were facing death. By retrospectively analyzing the results of the questionnaires collected before and after the assignments and exercises, we verified the educational effects and changes in the students' sense of ethics from participating in the group learning exercise; moreover, our results revealed the insight gained by the students in examining the experiences and challenges faced by terminally ill patients.


Asunto(s)
Estudiantes de Medicina , Estudiantes de Farmacia , Humanos , Estudios Retrospectivos , Escolaridad , Aprendizaje , Curriculum , Ética Médica
2.
Biol Pharm Bull ; 46(2): 257-262, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36724953

RESUMEN

Platelet-activating factor acetylhydrolase (PAF-AH) hydrolyzes an acetyl ester at the sn-2 position of platelet-activating factor (PAF), thereby mediating a variety of biological functions. PAF-AH is found in three isoforms: Type I PAF-AH (PAF-AH I) and Type II PAF-AH (PAF-AH II) are intracellular enzymes whereas plasma PAF-AH is characterized by association with lipoprotein in plasma. PAF-AH I forms a tetramer constituted by two catalytic subunits (α1 and α2) with ß regulatory subunits. We recently showed that a deficiency of PAF-AH I catalytic subunits in male mice caused an increase of body weight, food intake, and white adipose tissue (WAT) weight. In this study, we examined whether the expression of this enzyme was altered in the differentiation of 3T3-L1 preadipocytes into adipocytes. The amount of PAF-AH I α1 subunit protein was significantly reduced in 3T3-L1 differentiation, while the amount of the PAF-AH I α2 subunit was not changed. Immunoprecipitation analysis of 3T3-L1 differentiation showed that the complex of PAF-AH I catalytic subunits was changed from α1/α2 heterodimer to α2/α2 homodimer. Our findings suggest that changes in PAF-AH I catalytic subunits are involved in adipocyte differentiation of 3T3-L1 and obesity in mice.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa , Fosfolipasas A , Masculino , Ratones , Animales , Fosfolipasas A/metabolismo , Células 3T3-L1 , Dominio Catalítico , 1-Alquil-2-acetilglicerofosfocolina Esterasa/genética , Factor de Activación Plaquetaria/metabolismo , Diferenciación Celular
3.
Endocr J ; 69(10): 1261-1269, 2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-35675983

RESUMEN

Sulfonation is an important step in the metabolism of dopamine, estrogens, dehydroepiandrosterone, as well as thyroid hormones. However, the regulation of cytosolic sulfotransferases in the thyroid is not well understood. In a DNA microarray analysis of rat thyroid FRTL-5 cells, we found that the mRNA expression of 10 of 48 sulfotransferases was significantly altered by thyroid stimulating hormone (TSH), with that of sulfotransferase family 1A member 1 (SULT1A1) being the most significantly affected. Real-time PCR and Western blot analyses revealed that TSH, forskolin and dibutyryl cyclic AMP significantly suppressed SULT1A1 mRNA and protein levels in a time- and concentration-dependent manner. Moreover, immunofluorescence staining of FRTL-5 cells showed that SULT1A1 is localized in the perinuclear area in the absence of TSH but is spread throughout the cytoplasm with reduced fluorescence intensity in the presence of TSH. Sulfotransferase activity in FRTL-5 cells, measured using 3'-phosphoadenosine-5'-phosphosulfate as a donner and p-nitrophenol as an acceptor substrate, was significantly reduced by TSH. These findings suggest that the expression and activity of SULT1A1 are modulated by TSH in thyrocytes.


Asunto(s)
Células Epiteliales Tiroideas , Tirotropina , Ratas , Animales , Tirotropina/farmacología , Tirotropina/metabolismo , Células Epiteliales Tiroideas/metabolismo , Glándula Tiroides/metabolismo , Sulfotransferasas/genética , Sulfotransferasas/metabolismo , ARN Mensajero/metabolismo
4.
Artículo en Inglés | MEDLINE | ID: mdl-35462067

RESUMEN

Breast cancer is primarily classified into ductal and lobular types, as well as into noninvasive and invasive cancer. Invasive cancer involves lymphatic and hematogenous metastasis. In breast cancer patients with distant metastases, a neutrophil-derived serine protease; cathepsin G (Cat G), is highly expressed in breast cancer cells. Cat G induces cell migration and multicellular aggregation of MCF-7 human breast cancer cells; however, the mechanism is not clear. Recently, platelet-activating factor (PAF)-acetylhydrolase (PAF-AH), the enzyme responsible for PAF degradation, was reported to be overexpressed in some tumor types, including pancreatic and breast cancers. In this study, we investigated whether PAF-AH is involved in Cat G-induced aggregation and migration of MCF-7 cells. We first showed that Cat G increased PAF-AH activity and elevated PAFAH1B2 expression in MCF-7 cells. The elevated expression of PAFAH1B2 was also observed in human breast cancer tissue specimens by immunohistochemical analysis. Furthermore, knockdown of PAFAH1B2 in MCF-7 cells suppressed the cell migration and aggregation induced by low concentrations, but not high concentrations, of Cat G. Carbamoyl PAF (cPAF), a nonhydrolyzable PAF analog, completely suppressed Cat G-induced migration of MCF-7 cells. In addition, PAF receptor (PAFR) inhibition induced cell migration of MCF-7 cells even in the absence of Cat G, suggesting that Cat G suppresses the activation of PAFR through enhanced PAF degradation due to elevated expression of PAFAH1B2 and thereby induces malignant phenotypes in MCF-7 cells. Our findings may lead to a novel therapeutic modality for treating breast cancer by modulating the activity of Cat G/PAF signaling.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa , Neoplasias de la Mama , Catepsina G , Proteínas Asociadas a Microtúbulos , Factor de Activación Plaquetaria , 1-Alquil-2-acetilglicerofosfocolina Esterasa/biosíntesis , 1-Alquil-2-acetilglicerofosfocolina Esterasa/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Movimiento Celular , Femenino , Humanos , Células MCF-7 , Proteínas Asociadas a Microtúbulos/biosíntesis , Proteínas Asociadas a Microtúbulos/genética , Neutrófilos/metabolismo , Neutrófilos/patología , Factor de Activación Plaquetaria/metabolismo
5.
Biol Pharm Bull ; 44(7): 920-925, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34193688

RESUMEN

Type I platelet-activating factor-acetylhydrolase (PAF-AH) forms a complex consisting of two catalytic subunits (α1 and/or α2) with a regulatory subunit (ß). Although this protein was discovered as an enzyme that degrades an acetyl ester linked at the sn-2 position of platelet-activating factor (PAF), its physiological function remains unknown. In this study, to examine whether knockout mice lacking the catalytic subunits of this enzyme showed a different phenotype from that of wild-type mice, we measured and compared the body weights of knockout mice and control mice. The body weights of knockout mice were significantly increased compared to those of the control mice during 6 to 20 weeks from birth. Food intake was also significantly increased in knockout mice compared with control mice during these periods. Since a decrease in testis weight was reported in the knockout mice, we expected a decrease in testosterone levels. We measured and compared the amounts of testosterone in the serum and testis of knockout and control mice using liquid chromatography-tandem mass spectrometry, and found that testosterone levels in both the serum and testis were significantly decreased in the knockout mice compared with the control mice. These results suggest that a deficiency of type I PAF-AH catalytic subunits causes an increase in body weight, in part, due to reduced testosterone levels in male mice.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/deficiencia , Peso Corporal , 1-Alquil-2-acetilglicerofosfocolina Esterasa/genética , Tejido Adiposo Blanco , Animales , Dominio Catalítico , Hígado , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Tamaño de los Órganos , Testículo/anatomía & histología , Testículo/metabolismo , Testosterona/sangre , Testosterona/metabolismo
6.
Int J Mol Sci ; 22(14)2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-34299217

RESUMEN

The mycobacterial cell wall is composed of large amounts of lipids with varying moieties. Some mycobacteria species hijack host cells and promote lipid droplet accumulation to build the cellular environment essential for their intracellular survival. Thus, lipids are thought to be important for mycobacteria survival as well as for the invasion, parasitization, and proliferation within host cells. However, their physiological roles have not been fully elucidated. Recent studies have revealed that mycobacteria modulate the peroxisome proliferator-activated receptor (PPAR) signaling and utilize host-derived triacylglycerol (TAG) and cholesterol as both nutrient sources and evasion from the host immune system. In this review, we discuss recent findings that describe the activation of PPARs by mycobacterial infections and their role in determining the fate of bacilli by inducing lipid metabolism, anti-inflammatory function, and autophagy.


Asunto(s)
Infecciones por Mycobacterium/microbiología , Mycobacterium/metabolismo , Receptores Activados del Proliferador del Peroxisoma/metabolismo , Animales , Autofagia/fisiología , Colesterol/metabolismo , Humanos , Metabolismo de los Lípidos , Mycobacterium/crecimiento & desarrollo , Mycobacterium/inmunología , Infecciones por Mycobacterium/inmunología , Infecciones por Mycobacterium/metabolismo , Receptores Activados del Proliferador del Peroxisoma/genética , Transducción de Señal
7.
PLoS One ; 16(3): e0249184, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33770127

RESUMEN

Mycobacterium leprae (M. leprae) is the etiological agent of leprosy, and the skin lesions of lepromatous leprosy are filled with numerous foamy or xanthomatous histiocytes that are parasitized by M. leprae. Lipids are an important nutrient for the intracellular survival of M. leprae. In this study, we attempted to determine the intracellular lipid composition and underlying mechanisms for changes in host cell lipid metabolism induced by M. leprae infection. Using high-performance thin-layer chromatography (HPTLC), we demonstrated specific induction of triacylglycerol (TAG) production in human macrophage THP-1 cells following M. leprae infection. We then used [14C] stearic acid tracing to show incorporation of this newly synthesized host cell TAG into M. leprae. In parallel with TAG accumulation, expression of host glycerol-3-phosphate acyltransferase 3 (GPAT3), a key enzyme in de novo TAG synthesis, was significantly increased in M. leprae-infected cells. CRISPR/Cas9 genome editing of GPAT3 in THP-1 cells (GPAT3 KO) dramatically reduced accumulation of TAG following M. leprae infection, intracellular mycobacterial load, and bacteria viability. These results together suggest that M. leprae induces host GPAT3 expression to facilitate TAG accumulation within macrophages to maintain a suitable environment that is crucial for intracellular survival of these bacilli.


Asunto(s)
Mycobacterium leprae/genética , Mycobacterium leprae/metabolismo , Factor de Transcripción STAT3/genética , Triglicéridos/biosíntesis , Línea Celular , Expresión Génica , Humanos , Monocitos/citología
8.
Int J Mol Sci ; 20(4)2019 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-30813330

RESUMEN

Acyl-CoA:glycerol-sn-3-phosphate acyltransferase (GPAT) is an enzyme responsible for the rate-limiting step in the synthesis of glycerophospholipids and triacylglycerol (TAG). The enzymes of mammalian species are classified into four isoforms; GPAT1 and GPAT2 are localized in the mitochondrial outer membrane, whereas GPAT3 and GPAT4 are localized in the endoplasmic reticulum membrane. The activity of each enzyme expressed is associated with physiological and pathological functions. The transcriptional regulation is well known, particularly in GPAT1. GPAT1 mRNA expression is mainly regulated by the binding of the transcriptional factor SREBP-1c to the specific element (the sterol regulatory element) flanking the GPAT1 promoter. The TAG level is controlled by the insulin-induced transcriptional expression of GPAT1, which occupies most of the GPAT activity in the liver. The transcriptional regulation of the other three GPAT isoforms remains undetermined in detail. It is predicted that retinoic acid serves as a transcription factor in the GPAT2 promoter. PPARγ (peroxisome proliferator-activated receptor γ) increases the mRNA expression of GPAT3, which is associated with TAG synthesis in adipose tissues. Although GPAT has been considered to be a key enzyme in the production of TAG, unexpected functions have recently been reported, particularly in GPAT2. It is likely that GPAT2 is associated with tumorigenesis and normal spermatogenesis. In this review, the physiological and pathophysiological roles of the four GPAT isoforms are described, alongside the transcriptional regulation of these enzymes.


Asunto(s)
Regulación Enzimológica de la Expresión Génica , Glicerol-3-Fosfato O-Aciltransferasa/genética , Transcripción Genética , Secuencia de Aminoácidos , Animales , Carcinogénesis/patología , Glicerol-3-Fosfato O-Aciltransferasa/química , Glicerol-3-Fosfato O-Aciltransferasa/metabolismo , Humanos , Resistencia a la Insulina , Modelos Biológicos
9.
Clin Chim Acta ; 481: 184-188, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29550277

RESUMEN

BACKGROUND: Measurement of lipoprotein-associated phospholipase A2 (Lp-PLA2) can be used as an adjunct to traditional cardiovascular risk factors for identifying individuals at higher risk of cardiovascular events. This can be performed by quantification of the protein concentration using an ELISA platform or by measuring Lp-PLA2 activity using platelet-activating factor (PAF) analog as substrate. Here, an enzymatic Lp-PLA2 activity assay method using 1-O-Hexadecyl-2-acetyl-rac-glycero-3-phosphocholine (rac C16 PAF) was developed. METHODS: The newly revealed substrate specificity of lysoplasmalogen-specific phospholipase D (lysophospholipase D (LysoPLD)) was exploited. Lp-PLA2 hydrolyzes 1-O-Hexadecyl-2-acetyl-sn-glycero-3-phosphocholine (C16 PAF) to 1-O-Hexadecyl-2-hydroxy-sn-glycero-3-phosphocholine (LysoPAF). LysoPLD acted on LysoPAF, and the hydrolytically released choline was detected by choline oxidase. RESULTS: Regression analysis of Lp-PLA2 activity measured by the enzymatic Lp-PLA2 activity assay vs. two chemical Lp-PLA2 activity assays, i.e. LpPLA2 FS and PLAC® test, and ELISA, gave the following correlation coefficients: 0.990, 0.893 and 0.785, respectively (n = 30). CONCLUSION: Advantages of this enzymatic Lp-PLA2 activity assay compared with chemical Lp-PLA2 methods include the following; (i) only requires two reagents enabling a simple two-point linear calibration method with one calibrator (ii) no need for inhibitors of esterase-like activity in serum.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/sangre , Pruebas de Enzimas/métodos , 1-Alquil-2-acetilglicerofosfocolina Esterasa/metabolismo , Humanos , Análisis de Regresión
10.
Med Image Anal ; 39: 18-28, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28410505

RESUMEN

Automated organ segmentation from medical images is an indispensable component for clinical applications such as computer-aided diagnosis (CAD) and computer-assisted surgery (CAS). We utilize a multi-atlas segmentation scheme, which has recently been used in different approaches in the literature to achieve more accurate and robust segmentation of anatomical structures in computed tomography (CT) volume data. Among abdominal organs, the pancreas has large inter-patient variability in its position, size and shape. Moreover, the CT intensity of the pancreas closely resembles adjacent tissues, rendering its segmentation a challenging task. Due to this, conventional intensity-based atlas selection for pancreas segmentation often fails to select atlases that are similar in pancreas position and shape to those of the unlabeled target volume. In this paper, we propose a new atlas selection strategy based on vessel structure around the pancreatic tissue and demonstrate its application to a multi-atlas pancreas segmentation. Our method utilizes vessel structure around the pancreas to select atlases with high pancreatic resemblance to the unlabeled volume. Also, we investigate two types of applications of the vessel structure information to the atlas selection. Our segmentations were evaluated on 150 abdominal contrast-enhanced CT volumes. The experimental results showed that our approach can segment the pancreas with an average Jaccard index of 66.3% and an average Dice overlap coefficient of 78.5%.


Asunto(s)
Páncreas/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Abdomen/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados
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