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1.
J Appl Clin Med Phys ; 25(6): e14280, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38252745

RESUMEN

PURPOSE: This study evaluated the intra- and inter-fractional variation of tumors with fiducial markers (FMs), relative to the tumor-FM distance, to establish how close an FM should be inserted for respiratory-gated stereotactic body radiation therapy (RG-SBRT). METHODS: Forty-five lung tumors treated with RG-SBRT were enrolled. End-expiratory computed tomography (CT) (CTplan) and four-dimensional-CT (4D-CT) scans were obtained for planning. End-expiratory CT (CTfr) scanning was performed before each fraction. The FMs were divided into two groups based on the median tumor-FM distance in the CTplan (Dp). For the intra-fractional variation, the correlations between the corresponding tumor and FM intra-fractional motions, defined as the centroid coordinates of those in each 0-90% phase, with the 50% phase of 4D-CT as the origin, were calculated in the left-right, anterior-posterior, and superior-inferior directions. Furthermore, the maximum difference in the tumor-FM distance in each phase of 4D-CT scan, based on those in the 50% phase of 4D-CT scan (Dmax), was obtained. Inter-fractional variation was defined as the maximum distance between the tumors in CTplan and CTfr, when the CT scans were fused based on each FM or vertebra. RESULTS: The median Dp was 26.1 mm. While FM intra-fractional motions were significantly and strongly correlated with the tumor intra-fractional motions in only anterior-posterior and superior-inferior directions for the Dp > 26 mm group, they were significantly and strongly correlated in all directions for the Dp ≤ 26 mm group. In all directions, Dmax values of the Dp ≤ 26 mm group were lower than those of the Dp > 26 mm group. The inter-fractional variations based on the Dp ≤ 26 mm were smaller than those on the Dp > 26 mm and on the vertebra in all directions. CONCLUSIONS: Regarding intra- and inter-fractional variation, FMs for Dp ≤ 26 mm can increase the accuracy for RG-SBRT.


Asunto(s)
Marcadores Fiduciales , Tomografía Computarizada Cuatridimensional , Neoplasias Pulmonares , Radiocirugia , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada , Humanos , Radiocirugia/métodos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirugía , Neoplasias Pulmonares/patología , Planificación de la Radioterapia Asistida por Computador/métodos , Tomografía Computarizada Cuatridimensional/métodos , Masculino , Femenino , Radioterapia de Intensidad Modulada/métodos , Anciano , Respiración , Persona de Mediana Edad , Anciano de 80 o más Años , Tomografía Computarizada por Rayos X/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Movimiento , Pronóstico , Técnicas de Imagen Sincronizada Respiratorias/métodos , Órganos en Riesgo/efectos de la radiación
2.
Am J Physiol Cell Physiol ; 322(5): C948-C959, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35294847

RESUMEN

Sphingomyelin phosphodiesterase 1 (SMPD1) converts sphingomyelin into ceramide and phosphocholine; hence, loss of SMPD1 function causes abnormal accumulation of sphingomyelin in lysosomes, which results in the lipid-storage disorder Niemann-Pick disease (types A and B). SMPD1 activity is dependent on zinc, which is coordinated at the active site of the enzyme, and although SMPD1 has been suggested to acquire zinc at the sites where the enzyme is localized, precisely how SMPD1 acquires zinc remains to be clarified. Here, we addressed this using a gene-disruption/reexpression strategy. Our results revealed that Zn transporter 5 (ZNT5)-ZNT6 heterodimers and ZNT7 homodimers, which localize in the compartments of the early secretory pathway, play essential roles in SMPD1 activation. Both ZNT complexes contribute to cellular sphingolipid metabolism by activating SMPD1 because cells lacking the functions of the two complexes exhibited a reduced ceramide to sphingomyelin content ratio in terms of their dominant molecular species and an increase in the sphingomyelin content in terms of three minor species. Moreover, mutant cells contained multilamellar body-like structures, indicative of membrane stacking and accumulation, in the cytoplasm. These findings provide novel insights into the molecular mechanism underlying the activation of SMPD1, a key enzyme in sphingolipid metabolism.


Asunto(s)
Esfingolípidos , Esfingomielina Fosfodiesterasa , Ceramidas , Vías Secretoras , Esfingolípidos/metabolismo , Esfingomielina Fosfodiesterasa/genética , Esfingomielina Fosfodiesterasa/metabolismo , Esfingomielinas/metabolismo , Zinc/metabolismo
3.
J Org Chem ; 87(17): 11362-11368, 2022 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-35969667

RESUMEN

The development of protecting group-free synthesis has come to the forefront this century, as there is an increasing need to switch to greener synthetic methods. In peptide synthesis, a strategy of maximum protection offers the most efficient synthetic pathway, but minimal side chain protection is more favorable in terms of green chemistry. Here, we describe solid-phase peptide synthesis (SPPS) without hydroxy side chain protection based on an aqueous microwave (MW)-assisted method. First, we investigated the extent of O-acylation of the hydroxy side chain of Ser, Thr, and Tyr occurring in our method, which uses 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride. Under aqueous MW-assisted conditions, the coupling reaction proceeded efficiently without substantial O-acylation. Next, we applied the aqueous synthetic protocol without hydroxy side chain protection to synthesis of a laminin-related peptide, H-Tyr-Ile-Gly-Ser-Arg-NH2. HPLC analysis of the crude peptide revealed a single peak, suggesting the absence of side reactions including O-acylation and racemization. We also succeeded in synthesizing a difficult peptide sequence, acyl carrier protein (65-74) peptide, by aqueous SPPS without hydroxy or carboxamide side chain protection. Based on the eighth criterion of the 12 principles of green chemistry, namely, "reduce derivatives", our approach without hydroxy side chain protection will provide a greener peptide synthesis.


Asunto(s)
Técnicas de Síntesis en Fase Sólida , Agua , Secuencia de Aminoácidos , Microondas , Péptidos/química , Agua/química
4.
J Sci Food Agric ; 102(5): 1987-1994, 2022 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-34516661

RESUMEN

BACKGROUND: Chronic exposure to ultraviolet (UV) radiation promotes skin photoaging, which is clinically characterized by dryness, laxity, and wrinkling. Sea cucumber (Stichopus japonicus) (SC) is a marine organism with culinary and medicinal applications, especially in Asian countries. It is also a potential nutraceutical as it exhibits bioactive effects, such as antioxidant, antitumor, and anticancer activity. This study examined the effects of SC and its hydrolysate (SCH) on ultraviolet A (UVA) induced skin barrier function and wrinkle formation using hairless mice. RESULTS: Ultraviolet A significantly induced transepidermal water loss and wrinkle formation, which were significantly mitigated upon oral administration of SC and SCH. Sea cucumber also mitigated the UVA-induced downregulation of epidermal natural moisturizing factors and the upregulation of Aqp3, Mmp13, Tnfa, and Il6 mRNA levels in the mouse skin. CONCLUSION: Taken together, these results suggest that dietary SC and SCH exert anti-photoaging effects by modulating filaggrin synthesis and desquamation in the epidermis and regulating the NF-κB pathway in the skin. Our research indicates that SC and SCH have potential applications in nutricosmetics for photoaging. © 2021 Society of Chemical Industry.


Asunto(s)
Pepinos de Mar , Envejecimiento de la Piel , Animales , Suplementos Dietéticos , Ratones , Ratones Pelados , Piel , Rayos Ultravioleta/efectos adversos
5.
Mar Drugs ; 18(6)2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32492769

RESUMEN

Siphonaxanthin has been known to possess inhibitory effects against obesity, inflammation, and angiogenesis. However, little information on its in vivo bioavailability and biotransformation is available. To assess the bioavailability and metabolism of siphonaxanthin, its absorption and accumulation were evaluated using intestinal Caco-2 cells and Institute of Cancer Research (ICR) mice. Siphonaxanthin was absorbed and exhibited non-uniform accumulation and distribution patterns in tissues of ICR mice. Notably, in addition to siphonaxanthin, three main compounds were detected following dietary administration of siphonaxanthin. Because the compounds showed changes on mass spectra compared with that of siphonaxanthin, they were presumed to be metabolites of siphonaxanthin in ICR mice. Siphonaxanthin mainly accumulated in stomach and small intestine, while putative metabolites of siphonaxanthin mainly accumulated in liver and adipose tissues. Furthermore, siphonaxanthin and its putative metabolites selectively accumulated in white adipose tissue (WAT), especially mesenteric WAT. These results provide useful evidence regarding the in vivo bioactivity of siphonaxanthin. In particular, the results regarding the specific accumulation of siphonaxanthin and its metabolites in WAT have important implications for understanding their anti-obesity effects and regulatory roles in lipid metabolism.


Asunto(s)
Xantófilas/metabolismo , Xantófilas/farmacocinética , Tejido Adiposo , Tejido Adiposo Blanco , Animales , Disponibilidad Biológica , Células CACO-2 , Humanos , Metabolismo de los Lípidos , Hígado/metabolismo , Ratones , Distribución Tisular , Xantófilas/química
6.
Mar Drugs ; 18(12)2020 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-33255382

RESUMEN

Halocynthiaxanthin is an acetylenic carotenoid mainly found in Halocynthia roretzi. To date, several bioactivities of halocynthiaxanthin have been reported, but its mechanism of digestion and absorption in mammals has not been studied yet. In this study, we evaluated the intestinal absorption of halocynthiaxanthin in mice. The halocynthiaxanthin-rich fraction was prepared from the tunicate Halocynthia roretzi. Mice were orally administered the fraction at a dose of 5 mg/kg body weight. The halocynthiaxanthin levels in the plasma, liver, and small intestine, were quantified using HPLC-PDA, 1, 3, 6, and 9 h after ingestion. The halocynthiaxanthin-rich fraction mainly consisted of the all-trans form and a small amount of cis forms. These three isomers were detected in the plasma of mice 3 h after ingestion. Time-course changes after the ingestion of this fraction were found, with cis isomers being more abundant than the all-trans isomer in the mouse plasma and liver. In the small intestine, however, the all-trans isomer was primarily detected. The possibility that cis isomers might be absorbed rapidly from the small intestine cannot be denied, but our results suggest that dietary all-trans-halocynthiaxanthin might be isomerized to the cis isomer after intestinal absorption.


Asunto(s)
Absorción Intestinal , Intestino Delgado/metabolismo , Urocordados/metabolismo , Xantófilas/metabolismo , Administración Oral , Alimentación Animal , Animales , Masculino , Ratones Endogámicos ICR , Estereoisomerismo , Factores de Tiempo , Xantófilas/administración & dosificación , Xantófilas/sangre
7.
J Lipid Res ; 60(2): 333-340, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30552287

RESUMEN

Various functions of dietary sphingolipids have been reported; however, little is known about marine sphingolipids. Ceramide 2-aminoethylphosphonate (CAEP), an abundant sphingolipid in marine mollusks, frequently has a unique triene type of sphingoid base [2-amino-9-methyl-4,8,10-octadecatriene-1,3-diol (d19:3)]. We previously reported that dietary CAEP prepared from the skin of squid was digested in the intestinal mucosa of mice via ceramides to yield free sphingoid bases. How dietary CAEP is then used in the body remains unclear. Here, we investigated the absorption of dietary CAEP using a lipid absorption assay on the lymph collected from rats with thoracic duct cannulation. Our results reveal that sphingoid bases derived from CAEP, including d16:1, d18:1, and d19:3, were detected in the lymph after administration of CAEP. Lymphatic recovery of d19:3 was lower than that of other sphingoid bases. A large fraction of the absorbed sphingoid bases was present as complex sphingolipids, whereas a smaller portion was present in the free form. Fatty acids in ceramide moieties found in the lymph were partially different from dietary CAEP, which indicates that sphingoid bases derived from CAEP could be, at least in part, resynthesized into complex sphingolipids. Future studies should elucidate the metabolism of sphingoid bases derived from CAEP.


Asunto(s)
Absorción Fisicoquímica , Ácido Aminoetilfosfónico/análogos & derivados , Ceramidas/química , Carbohidratos de la Dieta , Linfa/metabolismo , Esfingolípidos/metabolismo , Absorción Fisicoquímica/efectos de los fármacos , Ácido Aminoetilfosfónico/química , Ácido Aminoetilfosfónico/farmacología , Animales , Ceramidas/farmacología , Carbohidratos de la Dieta/farmacología , Linfa/efectos de los fármacos , Ratas
8.
Proc Biol Sci ; 286(1907): 20191039, 2019 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-31311468

RESUMEN

Keto-carotenoids contribute to many important traits in animals, including vision and coloration. In a great number of animal species, keto-carotenoids are endogenously produced from carotenoids by carotenoid ketolases. Despite the ubiquity and functional importance of keto-carotenoids in animals, the underlying genetic architectures of their production have remained enigmatic. The body and eye colorations of spider mites (Arthropoda: Chelicerata) are determined by ß-carotene and keto-carotenoid derivatives. Here, we focus on a carotenoid pigment mutant of the spider mite Tetranychus kanzawai that, as shown by chromatography, lost the ability to produce keto-carotenoids. We employed bulked segregant analysis and linked the causal locus to a single narrow genomic interval. The causal mutation was fine-mapped to a minimal candidate region that held only one complete gene, the cytochrome P450 monooxygenase CYP384A1, of the CYP3 clan. Using a number of genomic approaches, we revealed that an inactivating deletion in the fourth exon of CYP384A1 caused the aberrant pigmentation. Phylogenetic analysis indicated that CYP384A1 is orthologous across mite species of the ancient Trombidiformes order where carotenoids typify eye and body coloration, suggesting a deeply conserved function of CYP384A1 as a carotenoid ketolase. Previously, CYP2J19, a cytochrome P450 of the CYP2 clan, has been identified as a carotenoid ketolase in birds and turtles. Our study shows that selection for endogenous production of keto-carotenoids led to convergent evolution, whereby cytochrome P450s were independently co-opted in vertebrate and invertebrate animal lineages.


Asunto(s)
Proteínas de Artrópodos/genética , Carotenoides/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Evolución Molecular , Pigmentación/genética , Tetranychidae/fisiología , Animales , Proteínas de Artrópodos/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Tetranychidae/genética
9.
Biosci Biotechnol Biochem ; 82(8): 1433-1436, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29625535

RESUMEN

We evaluated the distribution of astaxanthin in rat brains after a single dose administration and after feeding 0.1% astaxanthin diet for 5 days. Astaxanthin was detected in the hippocampus and cerebral cortex 4 and 8 h after a single dose. Astaxanthin concentration in rat brains was higher after consumption of astaxanthin diet for 5 days than after a single dose.


Asunto(s)
Antioxidantes/metabolismo , Corteza Cerebral/metabolismo , Dieta , Hipocampo/metabolismo , Animales , Antioxidantes/administración & dosificación , Antioxidantes/farmacología , Masculino , Estrés Oxidativo/efectos de los fármacos , Ratas Sprague-Dawley , Xantófilas/administración & dosificación , Xantófilas/sangre , Xantófilas/metabolismo , Xantófilas/farmacología
10.
PLoS Pathog ; 11(5): e1004909, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26020241

RESUMEN

Eukaryotic positive-strand RNA [(+)RNA] viruses are intracellular obligate parasites replicate using the membrane-bound replicase complexes that contain multiple viral and host components. To replicate, (+)RNA viruses exploit host resources and modify host metabolism and membrane organization. Phospholipase D (PLD) is a phosphatidylcholine- and phosphatidylethanolamine-hydrolyzing enzyme that catalyzes the production of phosphatidic acid (PA), a lipid second messenger that modulates diverse intracellular signaling in various organisms. PA is normally present in small amounts (less than 1% of total phospholipids), but rapidly and transiently accumulates in lipid bilayers in response to different environmental cues such as biotic and abiotic stresses in plants. However, the precise functions of PLD and PA remain unknown. Here, we report the roles of PLD and PA in genomic RNA replication of a plant (+)RNA virus, Red clover necrotic mosaic virus (RCNMV). We found that RCNMV RNA replication complexes formed in Nicotiana benthamiana contained PLDα and PLDß. Gene-silencing and pharmacological inhibition approaches showed that PLDs and PLDs-derived PA are required for viral RNA replication. Consistent with this, exogenous application of PA enhanced viral RNA replication in plant cells and plant-derived cell-free extracts. We also found that a viral auxiliary replication protein bound to PA in vitro, and that the amount of PA increased in RCNMV-infected plant leaves. Together, our findings suggest that RCNMV hijacks host PA-producing enzymes to replicate.


Asunto(s)
Nicotiana/virología , Ácidos Fosfatidicos/metabolismo , Fosfolipasa D/metabolismo , Hojas de la Planta/virología , ARN de Planta/genética , Tombusviridae/fisiología , Replicación Viral , Western Blotting , Silenciador del Gen , Inmunoprecipitación , Fosfolipasa D/antagonistas & inhibidores , Fosfolipasa D/genética , ARN Mensajero/genética , ARN Interferente Pequeño/genética , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
11.
J Nutr ; 145(3): 490-8, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25733464

RESUMEN

BACKGROUND: Siphonaxanthin, a xanthophyll present in green algae, has been shown to possess antiangiogenic and apoptosis-inducing activities. OBJECTIVE: We evaluated the antiobesity effects of siphonaxanthin by using a 3T3-L1 cell culture system and in diabetic KK-Ay mice. METHODS: 3T3-L1 cells were differentiated with or without 5 µmol/L siphonaxanthin, and lipid accumulation and critical gene expressions for adipogenesis were examined. In vivo, 4-wk-old male KK-Ay mice were administered daily oral treatment of 1.3 mg siphonaxanthin for 6 wk and body weight, visceral fat weight, serum variables, and gene expressions involved in lipid metabolism were evaluated. RESULTS: Compared with the other carotenoids evaluated, siphonaxanthin potently inhibited adipocyte differentiation. Siphonaxanthin significantly suppressed lipid accumulation at noncytotoxic concentrations of 2.5 and 5 µmol/L by 29% and 43%, respectively. The effects of siphonaxanthin were largely limited to the early stages of adipogenesis. Siphonaxanthin significantly inhibited protein kinase B phosphorylation by 48% and 72% at 90 and 120 min, respectively. The expressions of key adipogenesis genes, including CCAAT/enhancer binding protein α (Cebpa), peroxisome proliferator activated receptor γ (Pparg), fatty acid binding protein 4 (Fabp4), and stearoyl coenzyme A desaturase 1 (Scd1), were elevated by 1.6- to 166-fold during adipogenesis. After 8 d of adipocyte differentiation, siphonaxanthin significantly lowered gene expression of Cebpa, Pparg, Fabp4, and Scd1 by 94%, 83%, 95%, and 90%, respectively. Moreover, oral administration of siphonaxanthin to KK-Ay mice significantly reduced the total weight of white adipose tissue (WAT) by 13%, especially the mesenteric WAT by 28%. Furthermore, siphonaxanthin administration reduced lipogenesis and enhanced fatty acid oxidation in adipose tissue. Siphonaxanthin was observed to highly accumulate in mesenteric WAT, and the accumulation in the mesenteric WAT was almost 2- and 3-fold that in epididymal (P = 0.14) and perirenal (P < 0.05) WAT, respectively. CONCLUSION: These results provide evidence that siphonaxanthin may effectively regulate adipogenesis in 3T3-L1 cells and diabetic KK-Ay mice.


Asunto(s)
Adipocitos/efectos de los fármacos , Adipogénesis/efectos de los fármacos , Tejido Adiposo Blanco/efectos de los fármacos , Chlorophyta/química , Xantófilas/farmacología , Células 3T3-L1 , Adipogénesis/genética , Tejido Adiposo Blanco/metabolismo , Administración Oral , Animales , Glucemia/metabolismo , Proteínas Potenciadoras de Unión a CCAAT/genética , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Diferenciación Celular/efectos de los fármacos , Colesterol/sangre , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Ratones , PPAR gamma/genética , PPAR gamma/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Estearoil-CoA Desaturasa/genética , Estearoil-CoA Desaturasa/metabolismo , Triglicéridos/sangre
12.
Mar Drugs ; 12(6): 3660-8, 2014 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-24950294

RESUMEN

Siphonaxanthin is a specific keto-carotenoid in green algae whose bio-functional properties are yet to be identified. This review focuses on siphonaxanthin as a bioactive compound and outlines the evidence associated with functionality. Siphonaxanthin has been reported to potently inhibit the viability of human leukemia HL-60 cells via induction of apoptosis. In comparison with fucoxanthin, siphonaxanthin markedly reduced cell viability as early as 6 h after treatment. The cellular uptake of siphonaxanthin was 2-fold higher than fucoxanthin. It has been proposed that siphonaxanthin possesses significant anti-angiogenic activity in studies using human umbilical vein endothelial cells and rat aortic ring. The results of these studies suggested that the anti-angiogenic effect of siphonaxanthin is due to the down-regulation of signal transduction by fibroblast growth factor receptor-1 in vascular endothelial cells. Siphonaxanthin also exhibited inhibitory effects on antigen-induced degranulation of mast cells. These findings open up new avenues for future research on siphonaxanthin as a bioactive compound, and additional investigation, especially in vivo studies, are required to validate these findings. In addition, further studies are needed to determine its bioavailability and metabolic fate.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Chlorophyta/metabolismo , Xantófilas/farmacología , Inhibidores de la Angiogénesis/aislamiento & purificación , Animales , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Humanos , Ratas , Transducción de Señal/efectos de los fármacos , Xantófilas/aislamiento & purificación
13.
J Oleo Sci ; 73(1): 113-119, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38171727

RESUMEN

Cluster of differentiation 36 (CD36) is a scavenger receptor expressed in various vertebrate cells that contains diverse ligands, including long-chain fatty acids. This receptor has recently been suggested as a captor of specific volatile odorants (e.g., aliphatic acetates) in the mammalian nasal epithelium. This study used a fluorescence-intensifying assay to produce the first evidence that lauric acid, an odorous fatty acid, directly binds to CD36. This expansion of the repertoire of volatile ligands supports potential applications for nasal CD36. Our present findings could promote future research aimed at understanding the mechanisms of fatty acid interactions with CD36.


Asunto(s)
Antígenos CD36 , Ácidos Grasos , Animales , Antígenos CD36/metabolismo , Fluorescencia , Odorantes , Ácidos Láuricos , Mamíferos/metabolismo
14.
Phys Med Biol ; 69(5)2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38359451

RESUMEN

Objective. For response-adapted adaptive radiotherapy (R-ART), promising biomarkers are needed to predict post-radiotherapy (post-RT) responses using routine clinical information obtained during RT. In this study, a patient-specific biomechanical model (BM) of the head and neck squamous cell carcinoma (HNSCC) was proposed using the pre-RT maximum standardized uptake value (SUVmax) of18F-fluorodeoxyglucose (FDG) and tumor structural changes during RT as evaluated using computed tomography (CT). In addition, we evaluated the predictive performance of BM-driven imaging biomarkers for the treatment response of patients with HNSCC who underwent concurrent chemoradiotherapy (CCRT).Approach. Patients with histologically confirmed HNSCC treated with definitive CCRT were enrolled in this study. All patients underwent CT two times as follows: before the start of RT (pre-RT) and 3 weeks after the start of RT (mid-RT). Among these patients, 67 patients who underwent positron emission tomography/CT during the pre-RT period were included in the final analysis. The locoregional control (LC), progression-free survival (PFS), and overall survival (OS) prediction performances of whole tumor stress change (TS) between pre- and mid-RT computed using BM were assessed using univariate, multivariate, and Kaplan-Meier survival curve analyses, respectively. Furthermore, performance was compared with the pre and post-RT SUVmax, tumor volume reduction rate (TVRR) during RT, and other clinical prognostic factors.Main results. For both univariate, multivariate, and survival curve analyses, the significant prognostic factors were as follows (p< 0.05): TS and TVRR for LC; TS and pre-RT FDG-SUVmaxfor PFS; and TS only for OS. In addition, for 2 year LC, PFS, and OS prediction, TS showed a comparable predictive performance to post-RT FDG-SUVmax.Significance. BM-driven TS is an effective prognostic factor for tumor treatment response after CCRT. The proposed method can be a feasible functional imaging biomarker that can be acquired during RT using only routine clinical data and may provide useful information for decision-making during R-ART.


Asunto(s)
Fluorodesoxiglucosa F18 , Neoplasias de Cabeza y Cuello , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/diagnóstico por imagen , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/terapia , Radiofármacos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Quimioradioterapia/métodos , Biomarcadores , Tomografía de Emisión de Positrones/métodos
15.
Sci Rep ; 14(1): 2400, 2024 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-38287139

RESUMEN

Radiotherapy with deep inspiration breath hold (DIBH) reduces doses to the lungs and organs at risk. The stability of breath holding and reproducibility of tumor location are higher during expiration than during inspiration; therefore, we developed an irradiation method combining DIBH and real-time tumor-tracking radiotherapy (RTRT) (DBRT). Nine patients were enrolled in this study. Fiducial markers were placed near tumors using bronchoscopy. Treatment planning computed tomography (CT) was performed thrice during DIBH, assisted by spirometer-based device. Each CT scan was fused using fiducial markers. Gross tumor volume (GTV) was contoured for each dataset and summed to create GTVsum; adding a 5-mm margin around GTVsum generated the planning target volume. The prescribed dose was mainly 42 Gy in four fractions. The treatment plan was created using DIBH CT (DBRT-plan), with a similar treatment plan created for expiratory CT for cases for which DBRT could not be performed (conv-plan). Vx defined as the volume of the lung received x Gy, and the mean lung dose, V20, V10, and V5 were evaluated. DBRT was completed in all patients. Mean dose, V20, and V10 were significantly lower in the DBRT-plan than in the conv-plan (all p = 0.003). Mean rates of decrease for mean dose, V20, and V10 were 14.0%, 27.6%, and 19.1%, respectively. No significant difference was observed in V5. We developed DBRT, a stereotactic body radiation therapy performed with the DIBH technique; it combines a spirometer-based breath-hold support system with an RTRT system. All patients who underwent DBRT completed the procedure without any technical or mechanical complications. This is a promising methodology that may significantly reduce lung doses.


Asunto(s)
Neoplasias Pulmonares , Neoplasias de Mama Unilaterales , Humanos , Contencion de la Respiración , Reproducibilidad de los Resultados , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/radioterapia , Pulmón/diagnóstico por imagen , Pulmón/efectos de la radiación , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Órganos en Riesgo/efectos de la radiación , Corazón/efectos de la radiación , Neoplasias de Mama Unilaterales/radioterapia
16.
J Nutr Sci Vitaminol (Tokyo) ; 69(1): 62-70, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36858542

RESUMEN

Siphonein is a C19 acylated siphonaxanthin found in some edible green algae (e.g., Codium fragile and Caulerpa lentillifera). Although the content of siphonein in these green algae is similar to or higher than that of siphonaxanthin, studies of health-related biological activity of siphonein are much less than those of siphonaxanthin. Given the difference in the position of the acyl chain, one cannot infer intestinal absorption of siphonein from other general carotenoid fatty acid esters. In this study, we first investigated the intestinal absorption of siphonein using mouse and cell culture models. A small amount of siphonein was detected in the plasma of treated mice, and its concentration was higher than that of siphonaxanthin (i.e., the hydrolyzed product of ingested siphonein) from 1 to 6 h after administration. Pharmacological inhibition tests with differentiated Caco-2 cells showed that Nieman-Pick C1-like 1-mediated facilitated diffusion was involved in the cellular uptake of siphonein. These results indicate that, unlike general carotenoid fatty acid esters, siphonein can be absorbed without hydrolysis. We also evaluated the anti-inflammatory effect of siphonein in differentiated Caco-2 cells. Siphonein pretreatment modulated lipopolysaccharide-induced cellular lipidome alterations and suppressed mRNA expression of proinflammatory chemokines, CXCL8 protein release, and activation of NF-κB. This study provides new insights into the absorption processes of carotenoids and shows the anti-inflammatory effect of siphonein for the first time.


Asunto(s)
Chlorophyta , Absorción Intestinal , Animales , Ratones , Humanos , Células CACO-2 , Carotenoides , Ácidos Grasos , Antiinflamatorios , Ésteres
17.
Br J Radiol ; 96(1149): 20221149, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37393529

RESUMEN

OBJECTIVE: This study aims to retrospectively compare the stress map of the lung with pulmonary function test (PFT) results in lung cancer patients and to evaluate the potential of the stress map as an imaging biomarker for chronic obstructive pulmonary disease (COPD). METHODS: 25 lung cancer patients with pre-treatment four-dimensional CT (4DCT) and PFT data were retrospectively analysed. PFT metrics were used to diagnose obstructive lung disease. For each patient, forced expiratory volume in 1 s (FEV1 % predicted) and the ratio of FEV1 and forced vital capacity (FEV1/FVC) were recorded. 4DCT and biomechanical model-deformable image registration (BM-DIR) were used to obtain the lung stress map. The relationship between the mean of the total lung stress and PFT data was evaluated, and the COPD classification grade was also evaluated. RESULTS: The mean values of the total lung stress and FEV1 % predicted showed a significant strong correlation [R = 0.833, (p < 0.001)]. The mean values and FEV1/FVC showed a significant strong correlation [R = 0.805, (p < 0.001)]. For the total lung stress, the area under the curve and the optimal cut-off value were 0.94 and 510.8 Pa for the classification of normal or abnormal lung function, respectively. CONCLUSION: This study has demonstrated the potential of lung stress maps based on BM-DIR to accurately assess lung function by comparing them with PFT data. ADVANCES IN KNOWLEDGE: The derivation of stress map directly from 4DCT is novel method. The BM-DIR-based lung stress map can provide an accurate assessment of lung function.


Asunto(s)
Neoplasias Pulmonares , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Tomografía Computarizada Cuatridimensional , Estudios Retrospectivos , Pulmón/diagnóstico por imagen , Pruebas de Función Respiratoria/métodos , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico por imagen , Capacidad Vital
18.
Cancers (Basel) ; 15(17)2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-37686535

RESUMEN

This exploratory and retrospective study aimed to evaluate whether there is a difference in the overall survival (OS) rates of patients with stage IV lung cancer who underwent radiation therapy (RT) depending on the presence or absence of immune checkpoint inhibitors (ICIs) and the timing of their use. Eighty patients with histologically confirmed stage IV lung cancer were enrolled, and ICIs were administered to thirty (37.5%). ICIs were administered before RT and after RT in 11 and 20 patients, respectively. The median follow-up period was 6 (range: 1-37) months. Patients treated with ICIs had significantly better OS rates than those not treated with ICIs (p < 0.001). The 6-month OS rates in patients treated with and without ICIs were 76.3% and 34.5%, respectively. The group that received ICI therapy after RT had a significantly better OS rate than the group that received ICI therapy prior to RT (6-month OS: 94.7% vs. 40.0%, p < 0.001). In the multivariate analysis, performance status (0-1 vs. 2-4) and ICI use after RT were significant factors for OS (p = 0.032 and p < 0.001, respectively). Our results suggest that ICI administration after RT may prolong the OS of patients with stage IV lung cancer.

19.
J Pers Med ; 14(1)2023 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-38248726

RESUMEN

Unlike drug selection, radiation parameters (field, dose) are not based on driver gene mutations in patients with metastatic non-small cell lung cancer (NSCLC). This study aimed to compare radiosensitivity in NSCLC with and without EGFR driver gene mutations using clinical and in vitro data. The clinical study included 42 patients who underwent whole-brain radiotherapy for brain metastases from NSCLC; of these, 13 patients had EGFR mutation-positive tumors. The Kaplan-Meier method was used to calculate the cranial control rate without intracranial recurrence. In the in vitro study, colony formation and double-strand DNA breaks were examined in two EGFR mutation-negative and three EGFR mutation-positive NSCLC-derived cell lines. Colony formation was assessed 14 days after irradiation with 0 (control), 2, 4, or 8 Gy. DNA double-strand breaks were evaluated 0.5 and 24 h after irradiation. EGFR mutation-positive patients had a significantly better cranial control rates than EGFR mutation-negative patients (p = 0.021). EGFR mutation-positive cells formed significantly fewer colonies after irradiation with 2 or 4 Gy than EGFR mutation-negative cells (p = 0.002, respectively) and had significantly more DNA double-strand breaks at 24 h after irradiation (p < 0.001). Both clinical and in vitro data suggest that EGFR mutation-positive NSCLC is radiosensitive.

20.
Sci Rep ; 13(1): 13992, 2023 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-37634023

RESUMEN

Dietary information from aquatic organisms is instrumental in predicting biological interactions and understanding ecosystem functionality. In freshwater habitats, generalist fish species can access a diverse array of food sources from multiple food chains. These may include primary photosynthetic production and detritus derived from both oxic and anoxic decomposition. However, the exploitation of anoxic decomposition products by fish remains insufficiently explored. This study examines feeding habits of striped catfish (Pangasianodon hypophthalmus) at both adult and juvenile stages within a tropical reservoir, using stable carbon, nitrogen, and sulfur isotope ratios (δ13C, δ15N, and δ34S, respectively) and fatty acid (FA) analyses. The adult catfish exhibited higher δ15N values compared to primary consumers that feed on primary photosynthetic producers, which suggests ingestion of food sources originating from primary photosynthetic production-based food chains. On the other hand, juvenile catfish demonstrated lower δ15N values than primary consumers, correlating with low δ34S value and large proportions of bacterial FA but contained small proportions of polyunsaturated FA. This implies that juveniles utilize food sources from both anoxic decomposition and primary photosynthetic production-based food chains. Our results indicate that food chains based on anoxic decomposition can indeed contribute to the dietary sources of tropical fish species.


Asunto(s)
Bagres , Bagres/crecimiento & desarrollo , Bagres/fisiología , Animales , Cadena Alimentaria , Ecosistema , Tailandia , Sedimentos Geológicos
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