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1.
Magn Reson Imaging ; 112: 128-135, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38986889

RESUMEN

A multimodal brain function measurement system integrating functional magnetic resonance imaging (fMRI) and magnetoencephalography (MEG) is expected to be a tool that will provide new insights into neuroscience. To integrate fMRI and MEG, an ultra-low-field MRI (ULF-MRI) scanner that can generate a static magnetic field (B0) with an electromagnetic coil and turn off the B0 during MEG measurements is desirable. While electromagnetic B0 coil has the above advantages, it also has a trade-off between size and the broadness of the magnetic field homogeneity. In this study, we proposed a method for designing a B0 multi-stage circular coil arrangement that determines the number of coils required to maximize magnetic field homogeneity and minimize the total wiring length of the coils. The optimized multi-stage coil arrangement had an external shape of 600 mm in diameter and a maximum height of 600 mm, with an aperture of 600 mm in diameter and 300 mm in height. The magnetic field homogeneity was <100 ppm over a 210 mm diameter spherical volume (DSV). Compared to a previous two coil pairs arrangement with the same magnetic field homogeneity, the diameter was 1/1.9 times smaller, indicating that the newly designed B0 coil arrangement realized a smaller size and wider magnetic field homogeneity.

2.
Heliyon ; 10(12): e32512, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38952382

RESUMEN

Objective: Uncoupling protein 2 (UCP2) is an ion/anion transporter in the mitochondrial inner membrane that plays a crucial role in immune response, regulation of oxidative stress, and cellular metabolism. UCP2 polymorphisms are linked to chronic inflammation, obesity, diabetes, heart disease, exercise efficiency, and longevity. Daily step count and number of teeth are modifiable factors that reduce mortality risk, although the role of UCP2 in this mechanism is unknown. This study aimed to assess the possible effects of UCP2 polymorphisms on the association between daily step count and number of teeth with all-cause mortality. Methods: This study was conducted as a cohort project involving adult Japanese outpatients at Sado General Hospital (PROST). The final number of participants was 875 (mean age: 69 y). All-cause mortality during thirteen years (from June 2008 to August 2021) was recorded. The functional UCP2 genotypes rs659366 and rs660339 were identified using the Japonica Array®. Survival analyses were performed using multivariate Cox proportional hazard models. Results: There were 161 deaths (mean observation period: 113 months). Age, sex, daily step count, and the number of teeth were significantly associated with mortality. In females, UCP2 polymorphisms were associated with mortality independent of other factors (rs659366 GA compared to GG + AA; HR = 2.033, p = 0.019, rs660339 C T compared to CC + TT; HR = 1.911, p = 0.029). Multivariate models, with and without UCP2 genotypes, yielded similar results. The interaction terms between UCP2 genotype and daily step count or number of teeth were not significantly associated with mortality. Conclusion: The effects of UCP2 polymorphisms on the association between daily step count or the number of teeth and all-cause mortality were not statistically significant. In females, UCP2 polymorphisms were significantly associated with all-cause mortality. Our findings confirmed the importance of physical activity and oral health and suggested a role of UCP2 in mortality risk independently with those factors.

3.
Jpn Dent Sci Rev ; 59: 263-272, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37674898

RESUMEN

Rheumatoid arthritis (RA) is characterized by chronic inflammatory destruction of joint tissue and is caused by an abnormal autoimmune response triggered by interactions between genetics, environmental factors, and epigenetic and posttranslational modifications. RA has been suggested to be interrelated with periodontitis, a serious form or stage of chronic inflammatory periodontal disease associated with periodontopathic bacterial infections, genetic predisposition, environmental factors, and epigenetic influences. Over the last decade, a number of animal and clinical studies have been conducted to assess whether or not periodontitis and associated periodontopathic bacteria constitute risk factors for RA. The present review introduces recent accumulating evidence to support the associations of periodontitis and periodontopathic bacteria with the risk of RA or the outcome of RA pharmacological treatment with disease-modifying antirheumatic drugs. In addition, the results from intervention studies have suggested an improvement in RA clinical parameters after nonsurgical periodontal treatment. Furthermore, the potential causal mechanisms underlying the link between periodontitis and periodontopathic bacteria and RA are summarized.

4.
Biochem Biophys Res Commun ; 666: 179-185, 2023 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-37199136

RESUMEN

Hedgehog (Hh) signaling is involved in multiple biological events including development and cancers. It is processed through primary cilia, which are assembled from the mother centriole in most mammalian cells. Pancreatic ductal adenocarcinoma (PDAC) cells generally lose their primary cilia; thus, the Hh signaling pathway is postulated to be independent of the organelle in PDAC. We previously reported that the mother centriole-specific protein, centrosomal protein 164 (CEP164), is required for centriolar localization of the GLI2 transcription factor in Hh signaling and for suppressing the expression of Hh-target genes. In this study, we demonstrated the physical interaction between CEP164 and GLI2, and delineated their binding modes at the mother centriole. The ectopically expressed GLI2-binding region of CEP164 reduced the centriolar GLI2 localization and enhanced the expression of Hh-target genes in PDAC cells. Furthermore, similar phenotypes were observed in PDAC cells lacking primary cilia. These results suggest that the CEP164-GLI2 association at the mother centriole is responsible for controlling Hh signaling, independent of primary cilia in PDAC cells.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animales , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Proteína Gli2 con Dedos de Zinc/genética , Proteína Gli2 con Dedos de Zinc/metabolismo , Cilios/metabolismo , Transducción de Señal , Neoplasias Pancreáticas/patología , Carcinoma Ductal Pancreático/patología , Factores de Transcripción de Tipo Kruppel/metabolismo , Mamíferos/metabolismo , Neoplasias Pancreáticas
5.
Mod Rheumatol ; 33(1): 81-87, 2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-34865087

RESUMEN

OBJECTIVES: To assess whether periodontitis severity affects the clinical response to biological disease-modifying antirheumatic drugs (bDMARDs) for 1 year in rheumatoid arthritis (RA) patients. METHODS: Data were collected from 50 RA patients who had received corticosteroids, conventional synthetic DMARDs, or non-steroidal anti-inflammatory drugs before (baseline) and after 1 year of bDMARD therapy in a retrospective study. Rheumatologic conditions were compared between the two periodontitis severity groups according to the periodontal inflamed surface area (PISA) or Centers for Disease Control and Prevention (CDC)/American Academy of Periodontology (AAP) case definitions. RESULTS: Twenty-eight patients with no or mild periodontitis showed significantly greater decreases in changes in Clinical Disease Activity Index (CDAI) and tender and swollen joint count in comparison to 22 patients with moderate and severe periodontitis (p = .02, p = .01, and p = .03). Both bivariate and multivariate analyses revealed a significantly positive association between the baseline CDC/AAP definitions and CDAI changes (p = .005 and p = .0038). However, rheumatologic conditions were comparable between 25 patients each in the low and high PISA groups. CONCLUSIONS: Baseline periodontitis severity according to the CDC/AAP definitions is associated with the clinical response to bDMARDs for 1 year in RA patients.


Asunto(s)
Antirreumáticos , Artritis Reumatoide , Productos Biológicos , Periodontitis , Estados Unidos , Humanos , Antirreumáticos/uso terapéutico , Estudios de Seguimiento , Estudios Retrospectivos , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/complicaciones , Periodontitis/tratamiento farmacológico , Periodontitis/complicaciones , Productos Biológicos/uso terapéutico
6.
Mod Rheumatol ; 33(5): 918-927, 2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-35962564

RESUMEN

OBJECTIVES: The aim is to evaluate the relevance of serum immunoglobulin G (IgG) titres against periodontopathic bacteria to predict the clinical response to 1-year treatment with biological disease-modifying antirheumatic drugs (bDMARDs) in rheumatoid arthritis (RA) patients. METHODS: Data were collected from 50 RA patients who had received conventional synthetic DMARDs, corticosteroids, or non-steroidal anti-inflammatory drugs before (baseline) and after 1-year treatment with bDMARDs in a retrospective cohort study. Changes in rheumatologic conditions were compared between the two groups for low and high baseline IgG titres against Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans according to their median measurements. RESULTS: Twenty-five patients with low anti-P. gingivalis IgG titres showed significantly greater decreases in changes in the Clinical Disease Activity Index and swollen joint count than 25 patients with high anti-P. gingivalis IgG titres (p = .04 for both). Bivariate and multivariate analyses revealed a significantly positive association of baseline anti-P. gingivalis IgG titres with Clinical Disease Activity Index changes (p = .02 and p = .002). However, post-treatment rheumatologic conditions were comparable between 25 patients each in the low and high baseline anti-A. actinomycetemcomitans IgG titre groups. CONCLUSIONS: Baseline serum anti-P. gingivalis IgG titres are predictive of the clinical response to 1-year treatment with bDMARDs in RA patients.


Asunto(s)
Antirreumáticos , Artritis Reumatoide , Periodontitis , Humanos , Porphyromonas gingivalis , Periodontitis/tratamiento farmacológico , Estudios Retrospectivos , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Inmunoglobulina G
7.
AMB Express ; 12(1): 126, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36183035

RESUMEN

Carbon catabolite repression (CCR) enables preferential utilization of easily metabolizable carbon sources, implying the presence of mechanisms to ensure discriminatory gene repression depending on the ambient carbon sources. However, the mechanisms for such hierarchical repression are not precisely understood. In this report, we examined how deletion of pkaA and ganB, which encode cAMP signaling factors, and creA, which encodes a well-characterized repressor of CCR, affects CCR of hemicellulase genes in the filamentous fungus Aspergillus nidulans. ß-Xylanase production increased not only in ΔcreA but also in ΔpkaA and ΔganB, with the highest level observed in their double deletants, irrespective of the presence or absence of D-glucose. Expression of the ß-xylanase genes in the presence of D-glucose was de-repressed in all the deletion mutants, with significantly higher tolerance against D-glucose repression in ΔpkaA and ΔganB than in ΔcreA. In the presence of galactomannan and D-glucose, partial de-repression of ß-mannanase production was detected in ΔcreA, but not in ΔpkaA and ΔganB. The double deletion of creA/pkaA and creA/ganB led to earlier production. Release from D-glucose repression of the ß-mannanase genes was partial in the single deletants, while nearly full de-repression was observed in ΔcreAΔpkaA and ΔcreAΔganB. The contribution of PkaA and GanB to CCR by D-xylose of the ß-mannanase genes was very minor compared to that of CreA. Consequently, the present study revealed that cAMP signaling plays a major role in CCR of hemicellulase gene expression in a manner that is clearly independent from CreA.

8.
J Cell Sci ; 135(18)2022 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-36052645

RESUMEN

Primary cilia are near-ubiquitously assembled on cells in the human body, and are broadly associated with genetic diseases and cancers. In the early stage of ciliogenesis, the ciliary vesicle (CV) is formed on the mother centriole, which nucleates the primary cilium. However, the regulatory mechanisms underlying CV formation have not yet been fully elucidated. Here, we found that the atypical small GTPase RAB-like 3 (RABL3) is necessary to assemble primary cilia in human cells. RABL3 directly interacts with RAB11 (herein referring to both RAB11A and RAB11B), which is involved in CV formation. RABL3 localizes around the centrosome during early ciliogenesis, reminiscent of RAB11 dynamics. Furthermore, RABL3 positively controls the CV formation like RAB11. These findings suggest that RABL3 plays an important role, in cooperation with RAB11, in CV formation during early ciliogenesis.


Asunto(s)
Cilios , Proteínas de Unión al GTP rab , Centriolos/metabolismo , Centrosoma/metabolismo , Cilios/metabolismo , Vesículas Citoplasmáticas/metabolismo , Humanos , Proteínas de Unión al GTP rab/genética , Proteínas de Unión al GTP rab/metabolismo
9.
J Magn Reson ; 343: 107280, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35998483

RESUMEN

Among magnetic resonance imaging (MRI) techniques, ultra-low field (ULF) MRI has the potential to significantly lower the cost of implementation and maintenance, as well as the size of the scanning system. Due to the small amplitude of the signals produced by ULR-MRI, extremely sensitive magnetic sensors are required. Optically pumped magnetometers (OPMs) have been proposed for use in ULF-MRI as ultra-sensitive magnetic sensors capable of detecting very small signals. However, the cost of a ferromagnetic magnetic shield is often not affordable for many applications. By increasing the Larmor frequency, the influence of low-frequency magnetic noise can be mitigated, allowing OPM to be operated without the use of a magnetic shield chamber. This lowers the cost of the magnetic shield and further raises the signal strength, resulting in benefits such as non-prepolarization. We present a method for implementing the ULF-MRI using low-cost OPMs in this study. The Larmor frequency was adjusted to 300 kHz, and three-dimensional (3D) images of a phantom were acquired with a digital resolution of 3 × 3 × 3 mm3 using a static magnetic field of 7.05 mT without using a magnetic shield room or a prepolarization coil. Additionally, we corrected the frequency response to acquired images to consider the narrow bandwidth, and the SNR of 3D imaging was 18. The experimental results, we believe, establish a new guideline for higher-performance, lower-cost ULF-MRI that does not require expensive magnetic shielding.


Asunto(s)
Imagen por Resonancia Magnética , Imagen por Resonancia Magnética/métodos , Fantasmas de Imagen
10.
Life Sci Alliance ; 5(11)2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35803737

RESUMEN

Clustering of supernumerary centrosomes, which potentially leads to cell survival and chromosomal instability, is frequently observed in cancers. However, the molecular mechanisms that control centrosome clustering remain largely unknown. The centrosomal kinesin KIF24 was previously shown to restrain the assembly of primary cilia in mammalian cells. Here, we revealed that KIF24 depletion suppresses multipolar spindle formation by clustering centrosomes in pancreatic ductal adenocarcinoma (PDAC) cells harboring supernumerary centrosomes. KIF24 depletion also induced hyper-proliferation and improved mitotic progression in PDAC cells. In contrast, disruption of primary cilia failed to affect the proliferation and spindle formation in KIF24-depleted cells. These results suggest a novel role for KIF24 in suppressing centrosome clustering independent of primary ciliation in centrosome-amplified PDAC cells.


Asunto(s)
Carcinoma Ductal Pancreático , Centrosoma/fisiología , Cinesinas/metabolismo , Neoplasias Pancreáticas , Animales , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Supervivencia Celular/fisiología , Análisis por Conglomerados , Cinesinas/genética , Mamíferos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Huso Acromático/genética
11.
J Gen Appl Microbiol ; 68(1): 17-23, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35387910

RESUMEN

The His-Asp phosphorelay signal transduction from histidine kinase (HK) to the response regulator (RR) is an important mechanism for adaptation to environmental changes. Aspergillus nidulans expresses 15 different HKs, which may be involved in different types of adaptations. As reactive oxygen species (ROS) are a key signal of environmental changes, some HKs might be involved in ROS generation through transcriptional regulation. Previously, we identified 3 HK (NikA, FphA, and HysA) deletion strains that showed increased ROS production during growth. We also showed that the phosphorylation function of HysA is involved in ROS generation. Here, we investigated the role of HysA in ROS production in A. nidulans cells. HysA protein was detected in both the cytosol and mitochondria by biological fractionation of the vegetative cell lysate of A. nidulans. The subcellular localization analysis by expressing the the HysA-GFP fusion protein along with MitoTracker Red staining did not clearly reveal mitochondrial localization of HysA at the conidiophore during asexual development. However, mitochondrial ROS in hysA mutant strains were detected by MitoSOX Red staining, and their excess levels possibly caused morphological changes during asexual development.


Asunto(s)
Aspergillus nidulans , Aspergillus nidulans/genética , Aspergillus nidulans/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Histidina Quinasa/genética , Histidina Quinasa/metabolismo , Mitocondrias/metabolismo , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo
12.
Enzyme Microb Technol ; 145: 109762, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33750542

RESUMEN

Filamentous fungi belonging to the Aspergillus genus are one of the most favored microorganisms for industrial enzyme production because they can secrete large amounts of proteins into the culture medium. α-Amylase, an enzyme produced by Aspergillus species, is important for food and industrial applications. The production of α-amylase is induced by starch, mainly obtained from the edible biomass; however, the increasing demand for foods is limiting the application of the latter. Therefore, it is expected that using the non-edible biomass, such as rice straw, could improve the competition for industrial application starch containing resources. The transcription factor AmyR activates the transcription of amylolytic enzyme genes, while the transcription factor XlnR activates the transcription of xylanolytic enzyme genes in response to xylose. In this study, we aimed to construct an artificial AmyR::XlnR transcription factor (AXTF) by replacing the DNA-binding domain (1-159 amino acids) of XlnR with that (1-68 aa) of AmyR, which is capable of inducing amylolytic enzyme production in response to xylan-containing hemicellulosic biomass. The chimeric transcription factor AXTF was constructed and expressed using the gapA promoter in the amyR-deficient mutant strain SA1. When the AXTF strain was cultured in the minimal medium containing xylose as the carbon source, the amyB, amyF, agdB, and agdE transcription levels were 41.1-, 11.3-, 37.9-, and 23.7-fold higher, respectively, than those of the wild-type strain. The α-amylase and α-glucosidase activities in the culture supernatant of the AXTF strain grown with xylose for 48 h were 696.6 and 536.1 U/mL, respectively, while these activities were not detected in the culture supernatant of the wild-type and SA1 strains. When rice straw hydrolysate was used as a carbon source, the α-amylase and α-glucosidase activities were 590.2 and 362.7 U/mL, respectively. Thus, we successfully generated an Aspergillus nidulans strain showing amylolytic enzyme production in response to non-edible xylan-containing hemicellulosic biomass by transforming it with the chimeric transcription factor AXTF. Furthermore, the use of genes encoding engineered transcription factors is advantageous because introducing such genes into an industrial Aspergillus strain has similar simultaneous effects on multiple amylase genes controlled by AmyR.


Asunto(s)
Amilasas , Factores de Transcripción , Amilasas/genética , Biomasa , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Xilanos
13.
J Periodontal Res ; 56(4): 702-709, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33641208

RESUMEN

OBJECTIVE: The aim of the present study was to evaluate the association between the periodontal and serological parameters and the disease activity of rheumatoid arthritis (RA) and between the anti-agalactosyl immunoglobulin G (IgG) titer and periodontitis severity. The objective was also to assess the effect of supragingival scaling on the serological parameters in patients with RA. BACKGROUND: The periodontal and serological parameters in relation to the autoimmune inflammatory response have been linked to RA disease activity. However, the association of the anti-agalactosyl IgG titer with RA disease activity and periodontitis severity has not been elucidated. METHODS: The periodontal, rheumatologic, and serological data were collected from 127 patients with RA in a retrospective cohort study. Of the 127 patients, 21 had been randomly assigned to receive oral hygiene instruction and supragingival scaling. The anti-agalactosyl IgG titer was determined by an electrochemiluminescence immunoassay. RESULTS: The patients with a moderate to high RA disease activity showed significantly higher levels of probing depth (PD), clinical attachment level, anti-cyclic citrullinated peptide IgG, and anti-agalactosyl IgG titer and greater mean percentages of severe periodontitis than those with a low RA disease activity (p < .05 for all). Both univariate and multivariate analyses revealed a significantly positive correlation between the PD and RA disease activity (p = .009 and p = .001), between the anti-agalactosyl IgG titer and RA disease activity (p = .002 and p < .001), and between the anti-agalactosyl IgG titer and PD (p < .001 for both). Supragingival scaling significantly decreased the anti-agalactosyl IgG titer (p = 0.03). CONCLUSION: The PD and anti-agalactosyl IgG titer are positively interrelated, both of which are correlated positively with RA disease activity and influenced by supragingival scaling in patients with RA.


Asunto(s)
Artritis Reumatoide , Periodontitis , Autoanticuerpos , Humanos , Inmunoglobulina G , Estudios Retrospectivos
14.
J Magn Reson ; 324: 106910, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33482529

RESUMEN

Spin-lock preparation was studied to detect tiny oscillatory magnetic fields such as a neural magnetic field without the blood oxygen level-dependent effect. This approach is a direct measurement and independent of static magnetic field strength. Accordingly, it is anticipated as a feasible functional magnetic resonance imaging (fMRI) in low and ultra-low-field MRI. Several reports have been published on spin-lock preparation but reports on imaging simulation are rare. Research in this area can assist in investigating magnetic resonance signal changes and, accordingly, can help to develop new spin-lock methods. In this study, we propose an imaging simulation method with an analytical solution using the Bloch equation. To demonstrate the feasibility of our proposed method, we compared simulated images with experimental results in which the number of sub-voxels and the amplitude and phase of the target oscillatory magnetic fields varied. In addition, we also applied graphics processing unit parallel computing and investigated the feasibility of avoiding an impracticable calculation time by doing so.


Asunto(s)
Mapeo Encefálico/métodos , Imagen por Resonancia Magnética/métodos , Artefactos , Simulación por Computador , Fantasmas de Imagen
15.
Life Sci Alliance ; 4(3)2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33372037

RESUMEN

G protein-coupled receptors (GPCRs) are the most common pharmacological target in human clinical practice. To perform their functions, many GPCRs must accumulate inside primary cilia, microtubule-based plasma membrane protrusions working as cellular antennae. Nevertheless, the molecular mechanisms underlying GPCR ciliary targeting remain poorly understood. Serotonin receptor 6 (HTR6) and somatostatin receptor 3 (SSTR3) are two brain-enriched ciliary GPCRs involved in cognition and pathologies such as Alzheimer's disease and cancer. Although the third intracellular loops (IC3) of HTR6 and SSTR3 suffice to target non-ciliary GPCRs to cilia, these IC3s are dispensable for ciliary targeting of HTR6 and SSTR3 themselves, suggesting these GPCRs contain additional ciliary targeting sequences (CTSs). Herein, we discover and characterize novel CTSs in HTR6 and SSTR3 C-terminal tails (CT). These CT-CTSs (CTS2) act redundantly with IC3-CTSs (CTS1), each being sufficient for ciliary targeting. In HTR6, RKQ and LPG motifs are critical for CTS1 and CTS2 function, respectively, whereas in SSTR3 these roles are mostly fulfilled by AP[AS]CQ motifs in IC3 and juxtamembrane residues in CT. Furthermore, we shed light on how these CTSs promote ciliary targeting by modulating binding to ciliary trafficking adapters TULP3 and RABL2.


Asunto(s)
Membrana Celular/metabolismo , Cilios/metabolismo , Receptores de Serotonina/química , Receptores de Serotonina/metabolismo , Receptores de Somatostatina/química , Receptores de Somatostatina/metabolismo , Transducción de Señal/genética , Secuencia de Aminoácidos , Animales , Técnicas de Silenciamiento del Gen , Células HEK293 , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Ratones , Dominios y Motivos de Interacción de Proteínas , Transporte de Proteínas/genética , Transfección
16.
Magn Reson Med Sci ; 20(2): 166-174, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32389928

RESUMEN

PURPOSE: To analyze subcortical brain volume more reliably, we propose a deep learning segmentation method of subcortical brain based on magnetic resonance imaging (MRI) having high generalization performance, accuracy, and robustness. METHODS: First, local images of three-dimensional (3D) bounding boxes were extracted for seven subcortical structures (thalamus, putamen, caudate, pallidum, hippocampus, amygdala, and accumbens) from a whole brain MR image as inputs to the neural network. Second, dilated convolution layers, which input information of variable scope, were introduced to the blocks that make up the neural network. These blocks were connected in parallel to simultaneously process global and local information obtained by the dilated convolution layers. To evaluate generalization performance, different datasets were used for training and testing sessions (cross-dataset evaluation) because subcortical brain segmentation in clinical analysis is assumed to be applied to unknown datasets. RESULTS: The proposed method showed better generalization performance that can obtain stable accuracy for all structures, whereas the state-of-the-art deep learning method obtained extremely low accuracy for some structures. The proposed method performed segmentation for all samples without failing with significantly higher accuracy (P < 0.005) than conventional methods such as 3D U-Net, FreeSurfer, and Functional Magnetic Resonance Imaging of the Brain's (FMRIB's) Integrated Registration and Segmentation Tool in the FMRIB Software Library (FSL-FIRST). Moreover, when applying this proposed method to larger datasets, segmentation was robustly performed for all samples without producing segmentation results on the areas that were apparently different from anatomically relevant areas. On the other hand, FSL-FIRST produced segmentation results on the area that were apparently and largely different from the anatomically relevant area for about one-third to one-fourth of the datasets. CONCLUSION: The cross-dataset evaluation showed that the proposed method is superior to existing methods in terms of generalization performance, accuracy, and robustness.


Asunto(s)
Encéfalo/anatomía & histología , Encéfalo/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Procesamiento de Imagen Asistido por Computador/normas , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/normas , Reproducibilidad de los Resultados , Aprendizaje Profundo , Humanos , Redes Neurales de la Computación , Programas Informáticos
17.
Psychiatry Clin Neurosci ; 75(2): 46-56, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33090632

RESUMEN

AIM: Several studies have reported altered age-associated changes in white matter integrity in bipolar disorder (BD). However, little is known as to whether these age-related changes are illness-specific. We assessed disease-specific effects by controlling for age and investigated age-associated changes and Group × Age interactions in white matter integrity among major depressive disorder (MDD) patients, BD patients, and healthy controls. METHODS: Healthy controls (n = 96; age range, 20-77 years), MDD patients (n = 101; age range, 25-78 years), and BD patients (n = 58; age range, 22-76 years) participated in this study. Fractional anisotropy (FA) derived from diffusion tensor imaging in 54 white matter tracts were compared after controlling for the linear and quadratic effect of age using a generalized linear model. Age-related effects and Age × Group interactions were also assessed in the model. RESULTS: The main effect of group was significant in the left column and body of the fornix after controlling for both linear and quadratic effects of age, and in the left body of the corpus callosum after controlling for the quadratic effect of age. BD patients exhibited significantly lower FA relative to other groups. There was no Age × Group interaction in the tracts. CONCLUSION: Significant FA reductions were found in BD patients after controlling for age, indicating that abnormal white matter integrity in BD may occur at a younger age rather than developing progressively with age.


Asunto(s)
Trastorno Bipolar/patología , Trastorno Depresivo Mayor/patología , Sustancia Blanca/patología , Adulto , Factores de Edad , Anciano , Trastorno Bipolar/diagnóstico por imagen , Trastorno Depresivo Mayor/diagnóstico por imagen , Imagen de Difusión Tensora , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sustancia Blanca/diagnóstico por imagen , Adulto Joven
18.
Heliyon ; 6(11): e05531, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33294679

RESUMEN

BACKGROUND: Previous studies have reported associations between nonalcoholic fatty liver disease, periodontitis, and obesity. Serum immunoglobulin G (IgG) antibody titer against Porphyromonas gingivalis, a major pathogen of periodontitis, is an established indicator of periodontal infection. However, the relationship between the antibody titer and liver enzyme levels has not been clarified yet. A study in the elderly was needed to evaluate the effect of long-term persistent bacterial infection on liver function. The objective of this study was to investigate the association between liver function and infection by P. gingivalis, and the effect of obesity on the association. METHODS: A cross-sectional study was conducted in adult outpatients visiting Sado General Hospital, in Niigata Prefecture, Japan, from 2008 to 2010. The final participants included 192 men and 196 women (mean age 68.1 years). Multivariable logistic regression analyses were performed to assess the association between the serum IgG antibody titer and the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and γ-glutamine transferase (GGT) levels. RESULTS: In women, serum IgG antibody titers against P. gingivalis was associated with elevated ALT, but not with AST or GGT, independent of covariates (p = 0.015). No significant association was found between the antibody titer and the elevated liver enzymes in men. The effect of obesity on the relationship between antibody titer and liver enzyme levels was not statistically significant. CONCLUSIONS: A cross-sectional analysis of adult outpatients suggested an association between P. gingivalis infection and ALT levels in women. The effect of obesity on this association was not statistically significant.

19.
Front Cell Dev Biol ; 8: 587691, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33251215

RESUMEN

Primary cilia are hair-like projections that protrude from most mammalian cells and mediate various extracellular signaling pathways. Pancreatic ductal adenocarcinoma (PDAC) cells are known to lose their primary cilia, but the relevance of this phenomenon remains unclear. In this study, we generated PDAC-originated Panc1 cells devoid of primary cilia by mutating a centriolar protein, centrosomal protein 164 (CEP164), which is required for ciliogenesis. CEP164 depletion enhanced the clonogenicity of Panc1 cells, along with chemically induced elimination of primary cilia, suggesting that a lack of these organelles promotes PDAC cells proliferation. In addition, the loss of CEP164 altered the cell cycle progression irrespective of absence of primary cilia. We found that CEP164 was co-localized with the GLI2 transcription factor at the mother centriole and controlled its activation, thus inducing Cyclin D-CDK6 expression. Furthermore, CEP164-mutated Panc1 cells were significantly tolerant to KRAS depletion-dependent growth inhibition. This study suggests that CEP164 deficiency is advantageous for PDAC cells proliferation due to not only lack of ciliation but also cilia-independent GLI2-Cyclin D/CDK6 activation, and that CEP164 is a potential therapeutic target for PDAC.

20.
J Magn Reson ; 319: 106828, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33002769

RESUMEN

We demonstrated the feasibility of the spin-lock preparation sequence using low-field magnetic resonance (MR) imaging that prevents interference from blood-oxygenation-level-dependent effects. We focused on two spin-lock preparations: spin-lock Mz (SL-Mz) and stimulus-induced rotary saturation (SIRS) and analyzed the magnetization dynamics during the sequences using the Bloch equation. Next, we performed phantom experiments using a loop coil to investigate the MR signal change as a function of the target signal strength and phase. Furthermore, we performed curve fittings to consider the radio frequency, which agreed with the experimental results. Then, we investigated the detectable strength of the magnetic field, and the SL-Mz detected a signal strength of 2.34 nT. In conclusion, our experimental results showed good agreement with the results obtained using the Bloch equation.

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