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1.
Mol Oncol ; 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39400496

RESUMO

The Kirsten rat sarcoma (KRAS) oncogene was considered "undruggable" until the development of sotorasib, a KRASG12C selective inhibitor that shows favorable effects against lung cancers. MRTX1133, a novel KRASG12D inhibitor, has shown promising results in basic research, although its effects against pancreatic cancer are limited when used alone. Therefore, there is an urgent need to identify effective drugs that can be used in combination with KRAS inhibitors. In this study, we found that administration of the KRAS inhibitors sotorasib or MRTX1133 upregulated STAT3 phosphorylation and reactivated ERK through a feedback reaction. The addition of the MEK inhibitor trametinib and the JAK2 inhibitor fedratinib successfully reversed this effect and resulted in significant growth inhibition in vitro and in vivo. Analyses of sotorasib- and MRTX1133-resistant cells showed that trametinib plus fedratinib reversed the resistance to sotorasib or MRTX1133. These findings suggest that the JAK2-mediated pathway and reactivation of the MAPK pathway may play key roles in resistance to KRAS inhibitors in pancreatic cancers. Accordingly, simultaneous inhibition of KRAS, MEK, and JAK2 could be an innovative therapeutic strategy against KRAS-mutant pancreatic cancer.

2.
Genes Cells ; 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39380239

RESUMO

The cell cycle is driven by cyclin-dependent kinases (Cdks). The decision whether the cell cycle proceeds is made during G1 phase, when Cdk4/6 functions. Cyclin-dependent kinase inhibitor 2 (Cdkn2) is a specific inhibitor of Cdk4/6, and their interaction depends on D84 in Cdkn2 and R24/31 in Cdk4/6. This knowledge is based mainly on studies in mammalian cells. Here, we comprehensively analyzed Cdk4/6 and Cdkn2 in invertebrates and found that Cdk4/6 was present in most of the investigated phyla, but the distribution of Cdkn2 was rather uneven among and within the phyla. The positive charge of R24/R31 in Cdk4/6 was conserved in all analyzed species in phyla with Cdkn2. The presence of Cdkn2 and the conservation of the positive charge were statistically correlated. We also found that Cdkn2 has been tightly linked to Fas associated factor 1 (Faf1) during evolution. We discuss potential interactions between Cdkn2 and Cdk4/6 in evolution and the possible cause of the strong conservation of the microsynteny.

3.
Int J Mol Sci ; 25(20)2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39456874

RESUMO

Patients with chronic myeloid leukemia (CML) respond to tyrosine kinase inhibitors (TKIs); however, CML leukemic stem cells (LSCs) exhibit BCR::ABL kinase-independent growth and are insensitive to TKIs, leading to disease relapse. To prevent this, new therapies targeting CML-LSCs are needed. Rates of mitochondria-mediated oxidative phosphorylation (OXPHOS) in CD34+CML cells within the primitive CML cell population are higher than those in normal undifferentiated hematopoietic cells; therefore, the inhibition of OXPHOS in CML-LSCs may be a potential cure for CML. NK-128 (C33H61NO5S) is a structurally simplified analog of JCI-20679, the design of which was based on annonaceous acetogenins. NK-128 exhibits antitumor activity against glioblastoma and human colon cancer cells by inhibiting OXPHOS and activating AMP-activated protein kinase (AMPK). Here, we demonstrate that NK-128 effectively suppresses the growth of CML cell lines and that the combination of imatinib and NK-128 is more potent than either alone in a CML xenograft mouse model. We also found that NK-128 inhibits colony formation by CD34+ CML cells isolated from the bone marrow of untreated CML patients. Taken together, these findings suggest that targeting OXPHOS is a beneficial approach to eliminating CML-LSCs, and may improve the treatment of CML.


Assuntos
Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva , Células-Tronco Neoplásicas , Fosforilação Oxidativa , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Mesilato de Imatinib/farmacologia , Humanos , Fosforilação Oxidativa/efeitos dos fármacos , Animais , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Camundongos , Linhagem Celular Tumoral , Tiofenos/farmacologia , Tiofenos/química , Ensaios Antitumorais Modelo de Xenoenxerto , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
4.
ACS Macro Lett ; 13(9): 1171-1178, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39166800

RESUMO

This study aims to elucidate the origin of nonlinear stress relaxation behaviors in transient networks using a systematically controlled model system consisting of the tetra-armed polyethylene glycols (Tetra-PEG slime) in conjunction with two-dimensional rheo-optics observations. Transient networks, characterized by their temporary cross-links, are extensively utilized in self-healing and robust materials. However, the molecular mechanisms governing their viscoelastic responses to large deformations have remained elusive. This is primarily due to the heterogeneous structures inherent in conventional transient networks and a scarcity of detailed experimental evaluations. By employing Tetra-PEG slime, which is distinguished by its regular structure with uniform strand lengths and functionalities, and the polarization imaging method, we overcome these obstacles. Our results reveal that the damping phenomena observed under large step strains arise from spatially heterogeneous relaxation, predominantly driven by network strand pullout. These insights lay a solid foundation for understanding the intricate rheological properties of transient networks.

5.
Artigo em Inglês | MEDLINE | ID: mdl-39095055

RESUMO

OBJECTIVES: This study evaluated the feasibility of a model-based iterative reconstruction technique (MBIR) tuned for the myocardium on myocardial computed tomography late enhancement (CT-LE). METHODS: Twenty-eight patients who underwent myocardial CT-LE and late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) within 1 year were retrospectively enrolled. Myocardial CT-LE was performed using a 320-row CT with low tube voltage (80 kVp). Myocardial CT-LE images were scanned 7 min after CT angiography (CTA) without additional contrast medium. All myocardial CT-LE images were reconstructed with hybrid iterative reconstruction (HIR), conventional MBIR (MBIR_cardiac), and new MBIR tuned for the myocardium (MBIR_myo). Qualitative (5-grade scale) scores and quantitative parameters (signal-to-noise ratio [SNR] and contrast-to-noise ratio [CNR]) were assessed as image quality. The sensitivity, specificity, and accuracy of myocardial CT-LE were evaluated at the segment level using an American Heart Association (AHA) 16-segment model, with LGE-MRI as a reference standard. These results were compared among the different CT image reconstructions. RESULTS: In 28 patients with 448 segments, 160 segments were diagnosed with positive by LGE-MRI. In the qualitative assessment of myocardial CT-LE, the mean image quality scores were 2.9 ± 1.2 for HIR, 3.0 ± 1.1 for MBIR_cardiac, and 4.0 ± 1.0 for MBIR_myo. MBIR_myo showed a significantly higher score than HIR (P < 0.001) and MBIR_cardiac (P = 0.018). In the quantitative image quality assessment of myocardial CT-LE, the median image SNR was 10.3 (9.1-11.1) for HIR, 10.8 (9.8-12.1) for MBIR_cardiac, and 16.8 (15.7-18.4) for MBIR_myo. The median image CNR was 3.7 (3.0-4.6) for HIR, 3.8 (3.2-5.1) for MBIR_cardiac, and 6.4 (5.0-7.7) for MBIR_myo. MBIR_myo significantly improved the SNR and CNR of CT-LE compared to HIR and MBIR_cardiac (P < 0.001). The sensitivity, specificity, and accuracy for the detection of myocardial CT-LE were 70%, 92%, and 84% for HIR; 71%, 92%, and 85% for MBIR_cardiac; and 84%, 92%, and 89% for MBIR_myo, respectively. MBIR_myo showed significantly higher image quality, sensitivity, and accuracy than the others (P < 0.05). CONCLUSIONS: MBIR tuned for myocardium improved image quality and diagnostic performance for myocardial CT-LE assessment.

6.
J Am Chem Soc ; 146(29): 20122-20132, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38985988

RESUMO

Structure-function relationships of supported metal nanoparticle catalysts in the CO-assisted oxidation of ethane to ethanol were investigated. A rutile TiO2-supported Pt nanoparticle catalyst exhibited the highest ethanol production rate and selectivity. During the reaction, sequential changes in the geometric/electronic states and the particle size of the Pt nanoparticles were observed. The comparison of the catalytic performances of model catalysts with controlled metal-support interactions revealed that Pt0 nanoparticles of 2-3 nm with a high fraction of the surface Ptδ+ species are highly active for the oxidation of ethane to ethanol. The coadded CO plays a pivotal role not only in tuning the oxidation state of the surface Pt but also in producing H2O2, which is the true oxidant for the reaction. The supported Pt nanoparticle uses in situ-generated H2O2 to activate ethane, where the C2H5OOH intermediate is formed through a nonradical mechanism and subsequently converted to C2H5OH. This reaction occurs even at 50 °C with an apparent activation energy of 32 kJ mol-1. The present study sheds light on the usefulness of surface-engineered Pt nanoparticles for the low-temperature oxidation of ethane to ethanol.

7.
J Am Chem Soc ; 146(28): 19599-19608, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38952064

RESUMO

Crystalline polyethylenes bearing carboxylic acid groups in the main chain were successfully degraded with a Ce catalyst and visible light. The reaction proceeds in a crystalline solid state without swelling in acetonitrile or water at a reaction temperature as low as 60 or 80 °C, employing dioxygen in air as the only stoichiometric reactant with nearly quantitative recovery of carbon atoms. Heterogeneous features of the reaction allowed us to reveal a dynamic morphological change of polymer crystals during the degradation.

8.
Sci Rep ; 14(1): 14358, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38906976

RESUMO

A intermediate multidomain state and large crystallographic tilting of 1.78° for the (hh0)pc planes of a (001)pc-oriented single-domain Mn-doped BiFeO3 (BFMO) thin film were found when an electric field was applied along the [110]pc direction. The anomalous crystallographic tilting was caused by ferroelastic domain switching of the 109° domain switching. In addition, ferroelastic domain switching occurred via an intermediate multidomain state. To investigate these switching dynamics under an electric field, we used in situ fluorescent X-ray induced Kossel line pattern measurements with synchrotron radiation. In addition, in situ inverse X-ray fluorescence holography (XFH) experiments revealed that atomic displacement occurred under an applied electric field. We attributed the atomic displacement to crystallographic tilting induced by a converse piezoelectric effect. Our findings provide important insights for the design of piezoelectric and ferroelectric materials and devices.

9.
Cancer Res Commun ; 4(7): 1802-1814, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38881188

RESUMO

Recent progress in single-cell profiling technologies has revealed significant phenotypic and transcriptional heterogeneity in tumor-infiltrating CD8+ T cells. However, the transition between the different states of intratumoral antigen-specific CD8+ T cells remains elusive. Here, we sought to examine the generation, transcriptomic states, and the clinical relevance of melanoma-infiltrating CD8+ T cells expressing a chemokine receptor and T-cell differentiation marker, CX3C chemokine receptor 1 (CX3CR1). Analysis of single-cell datasets revealed distinct human melanoma-infiltrating CD8+ T-cell clusters expressing genes associated with effector T-cell function but with distinguishing expression of CX3CR1 or PDCD1. No obvious impact of CX3CR1 expression in melanoma on the response to immune checkpoint inhibitor therapy was observed while increased pretreatment and on-treatment frequency of a CD8+ T-cell cluster expressing high levels of exhaustion markers was associated with poor response to the treatment. Adoptively transferred antigen-specific CX3CR1- CD8+ T cells differentiated into the CX3CR1+ subset in mice treated with FTY720, which inhibits lymphocyte egress from secondary lymphoid tissues, suggesting the intratumoral generation of CX3CR1+ CD8+ T cells rather than their trafficking from secondary lymphoid organs. Furthermore, analysis of adoptively transferred antigen-specific CD8+ T cells, in which the Cx3cr1 gene was replaced with a marker gene confirmed that CX3CR1+ CD8+ T cells could directly differentiate from the intratumoral CX3CR1- subset. These findings highlight that tumor antigen-specific CX3CR1- CD8+ T cells can fully differentiate outside the secondary lymphoid organs and generate CX3CR1+ CD8+ T cells in the tumor microenvironment, which are distinct from CD8+ T cells that express markers of exhaustion. SIGNIFICANCE: Intratumoral T cells are composed of heterogeneous subpopulations with various phenotypic and transcriptional states. This study illustrates the intratumoral generation of antigen-specific CX3CR1+ CD8+ T cells that exhibit distinct transcriptomic signatures and clinical relevance from CD8+ T cells expressing markers of exhaustion.


Assuntos
Linfócitos T CD8-Positivos , Receptor 1 de Quimiocina CX3C , Linfócitos do Interstício Tumoral , Melanoma , Transcriptoma , Receptor 1 de Quimiocina CX3C/genética , Receptor 1 de Quimiocina CX3C/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Melanoma/imunologia , Melanoma/genética , Melanoma/patologia , Animais , Humanos , Camundongos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Cloridrato de Fingolimode/farmacologia , Cloridrato de Fingolimode/uso terapêutico , Camundongos Endogâmicos C57BL , Análise de Célula Única , Relevância Clínica
11.
ACS Omega ; 9(10): 11942-11949, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38496950

RESUMO

Sandwich culture systems are techniques that cultivate cells by sandwiching them between the top and bottom substrates. Since the substrates can be separated, the system is expected to be applied to the construct layering of patterned cells and to the isolation of stacked cells. In this study, we prepared hydrogels composed of zwitterionic sulfabetaine polymers, poly[2-(2-(methacryloyloxyethyl)dimethylammonio)ethyl-1-sulfate] (PZBMA). The ZBMA homopolymers have been shown to form aggregates in aqueous solutions due to their intermolecular interactions. The water content of the PZBMA hydrogels in water was ∼70% regardless of N,N'-methylenebis(acrylamide), BIS, content as the cross-linker. The results indicated that the intermolecular interaction contributed more to the swelling behaviors than the chemical cross-linker. However, PZBMA hydrogels with 0.1 mol % BIS showed not only high elongation (∼850%) properties but also high adhesiveness and self-healing properties. When this PZBMA hydrogel was impregnated with collagen and subjected to sandwich culture using Madin-Darby canine kidney (MDCK) cells, a three-dimensional morphology of MDCK cell aggregates was constructed. Such a sulfabetaine hydrogel is expected to be developed for regenerative medicine.

12.
J Surg Oncol ; 129(5): 922-929, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38173362

RESUMO

BACKGROUND AND OBJECTIVES: Robotic distal gastrectomy (RDG) has been widely performed throughout Japan since it became insured in 2018. This study aimed to evaluate the short-term outcomes of RDG and laparoscopic distal gastrectomy (LDG) for gastric cancer using real-world data. METHODS: A total of 4161 patients who underwent LDG (n = 3173) or RDG (n = 988) for gastric cancer between April 2018 and October 2022 were identified through the Japanese Diagnosis Procedure Combination Database, which covers 42 national university hospitals. The primary outcome was postoperative in-hospital mortality rate. The secondary outcomes were postoperative complication rates, time to diet resumption, and postoperative length of stay (LOS). RESULTS: In-hospital mortality and postoperative complication rates in the RDG group were comparable with those in the LDG group (0.1% vs. 0.0%, p = 1.000, and 8.7% vs. 8.2%, p = 0.693, respectively). RDG was associated with a longer duration of anesthesia (325 vs. 262 min, p < 0.001), similar time to diet resumption (3 vs. 3 days, p < 0.001), and shorter postoperative LOS (10 vs. 11 days, p < 0.001) compared with LDG. CONCLUSIONS: RDG was performed safely and provided shorter postoperative LOS, since it became covered by insurance in Japan.


Assuntos
Laparoscopia , Procedimentos Cirúrgicos Robóticos , Neoplasias Gástricas , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Japão/epidemiologia , Pacientes Internados , Gastrectomia/métodos , Resultado do Tratamento , Laparoscopia/métodos , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos
13.
Blood Adv ; 8(6): 1345-1358, 2024 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-38190613

RESUMO

ABSTRACT: Adult T-cell leukemia/lymphoma (ATL) is triggered by infection with human T-cell lymphotropic virus-1 (HTLV-1). Here, we describe the reprogramming of pyrimidine biosynthesis in both normal T cells and ATL cells through regulation of uridine-cytidine kinase 2 (UCK2), which supports vigorous proliferation. UCK2 catalyzes the monophosphorylation of cytidine/uridine and their analogues during pyrimidine biosynthesis and drug metabolism. We found that UCK2 was overexpressed aberrantly in HTLV-1-infected T cells but not in normal T cells. T-cell activation via T-cell receptor (TCR) signaling induced expression of UCK2 in normal T cells. Somatic alterations and epigenetic modifications in ATL cells activate TCR signaling. Therefore, we believe that expression of UCK2 in HTLV-1-infected cells is induced by dysregulated TCR signaling. Recently, we established azacitidine-resistant (AZA-R) cells showing absent expression of UCK2. AZA-R cells proliferated normally in vitro, whereas UCK2 knockdown inhibited ATL cell growth. Although uridine and cytidine accumulated in AZA-R cells, possibly because of dysfunction of pyrimidine salvage biosynthesis induced by loss of UCK2 expression, the amount of UTP and CTP was almost the same as in parental cells. Furthermore, AZA-R cells were more susceptible to an inhibitor of dihydroorotic acid dehydrogenase, which performs the rate-limiting enzyme of de novo pyrimidine nucleotide biosynthesis, and more resistant to dipyridamole, an inhibitor of pyrimidine salvage biosynthesis, suggesting that AZA-R cells adapt to UCK2 loss by increasing de novo pyrimidine nucleotide biosynthesis. Taken together, the data suggest that fine-tuning pyrimidine biosynthesis supports vigorous cell proliferation of both normal T cells and ATL cells.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano , Pirimidinas , Adulto , Humanos , Uridina/metabolismo , Proliferação de Células , Citidina , Nucleotídeos de Pirimidina , Receptores de Antígenos de Linfócitos T , Linfócitos T/metabolismo
14.
Oncology ; 102(2): 114-121, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37699374

RESUMO

INTRODUCTION: Ovarian metastasis of colorectal cancer is known to have a poor prognosis. This study aimed to elucidate the characteristics of patients who underwent oophorectomy for ovarian metastasis from colorectal cancer. METHODS: This retrospective study included 16 patients who underwent oophorectomy for colorectal cancer metastasis to the ovary from January 2004 to December 2017. Improvement in patient's symptoms and pre- and postoperative changes in various nutritional and inflammatory indicators were assessed. Survival analysis and identification of prognostic factors were conducted with a median follow-up of 40.7 (5-109) months. RESULTS: Of 16 patients, 12 had (75%) synchronous and 4 (25%) had metachronous metastasis. Fourteen patients were symptomatic but symptoms resolved postoperatively. Thirteen patients (81.3%) had ascites and 5 (31.3%) had pleural effusion on preoperative computed tomography that disappeared after surgery in all cases. The median value of prognostic nutritional factor was significantly increased postoperatively (36.0 [preoperatively] vs. 47.5, p < 0.0001). The median (interquartile range) values for lymphocyte-C-reactive protein ratio were 715.2 (110-2,607) preoperatively and 6,095.2 (1,612.3-14,431.8) postoperatively (p = 0.0214). The median survival of the entire cohort was 60.4 months. The 3-year survival rates for R0 + R1 and R2 cases were 83% and 24% (p = 0.018), respectively. Univariate analysis showed that R2 resection and low postoperative lymphocyte-C-reactive protein ratio were associated with poor prognosis. CONCLUSIONS: Oophorectomy for ovarian metastasis from colorectal cancers was safely performed. It improved the patients' symptoms and nutritional status and may result in improved prognosis.


Assuntos
Adenocarcinoma , Neoplasias Colorretais , Neoplasias Ovarianas , Feminino , Humanos , Neoplasias Ovarianas/cirurgia , Estudos Retrospectivos , Proteína C-Reativa , Estado Nutricional , Neoplasias Colorretais/patologia , Ovariectomia/métodos , Prognóstico , Adenocarcinoma/cirurgia , Adenocarcinoma/secundário
15.
J Dermatol Sci ; 113(1): 10-17, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38158274

RESUMO

BACKGROUND: The epidermis contains many structurally diverse ceramides, which form the skin permeability barrier (skin barrier). Mutations in genes involved in the synthesis of ω-O-acylceramides (acylceramides) and protein-bound ceramides cause ichthyosis. OBJECTIVE: We aimed to elucidate the relationship between the degree of skin barrier impairment and changes in epidermal ceramide profiles caused by mutations in acylceramide synthesis genes. METHODS: Knockout (KO) mice of three genes-fatty acid (FA) ω-hydroxylase Cyp4f39 (human CYP4F22 ortholog), FA elongase Elovl1, and acyl-CoA synthetase Fatp4-were subjected to transepidermal water loss measurement, toluidine blue staining, and epidermal ceramide profiling via liquid chromatography coupled with tandem mass spectrometry. RESULTS: Transepidermal water loss was highest in Cyp4f39 KO mice, followed by Elovl1 KO and Fatp4 KO mice, and Cyp4f39 KO mice also showed the strongest degree of toluidine blue staining. In Cyp4f39 KO, Elovl1 KO, and Fatp4 KO mice, acylceramide levels were 0.6%, 1.6%, and 12%, respectively, of those in wild-type mice. Protein-bound ceramide levels were 0.2%, 30%, and 33%, respectively, of those in wild-type mice. We also observed a near-complete absence of ω-hydroxy ceramides in Cyp4f39 KO mice, reduced total ceramide levels and shortened FA moieties in Elovl1 KO mice, and increased hydroxylated ceramide levels and slightly shortened FA moieties in Fatp4 KO mice. CONCLUSIONS: The degree of reduction in protein-bound ceramide levels is probably related to the severity of skin barrier defects in these three strains. However, reduced acylceramide levels and other changes in ceramide composition unique to each KO strain are also involved.


Assuntos
Ceramidas , Pele , Animais , Humanos , Camundongos , Epiderme , Camundongos Knockout , Cloreto de Tolônio , Água
16.
Front Radiol ; 3: 1214521, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38105799

RESUMO

Rationale and objectives: We aimed to evaluate the impact of four-dimensional noise reduction filtering using a four-dimensional similarity filter (4D-SF) on radiation dose reduction in dynamic myocardial computed tomography perfusion (CTP). Materials and methods: Forty-three patients who underwent dynamic myocardial CTP using 320-row computed tomography (CT) were included in the study. The original images were reconstructed using iterative reconstruction (IR). Three different CTP datasets with simulated noise, corresponding to 25%, 50%, and 75% reduction of the original dose (300 mA), were reconstructed using a combination of IR and 4D-SF. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were assessed, and CT-derived myocardial blood flow (CT-MBF) was quantified. The results were compared between the original and simulated images with radiation dose reduction. Results: The median SNR (first quartile-third quartile) at the original, 25%-, 50%-, and 75%-dose reduced-simulated images with 4D-SF was 8.3 (6.5-10.2), 16.5 (11.9-21.7), 15.6 (11.0-20.1), and 12.8 (8.8-18.1) and that of CNR was 4.4 (3.2-5.8), 6.7 (4.6-10.3), 6.6 (4.3-10.1), and 5.5 (3.5-9.1), respectively. All the dose-reduced-simulated CTPs with 4D-SF had significantly higher image quality scores in SNR and CNR than the original ones (25%-, 50%-, and 75%-dose reduced vs. original images, p < 0.05, in each). The CT-MBF in 75%-dose reduced-simulated CTP was significantly lower than 25%-, 50%- dose-reduced-simulated, and original CTPs (vs. 75%-dose reduced-simulated images, p < 0.05, in each). Conclusion: 4D-SF has the potential to reduce the radiation dose associated with dynamic myocardial CTP imaging by half, without impairing the robustness of MBF quantification.

17.
Int J Mol Sci ; 24(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38003303

RESUMO

In our preliminary experiment, peritoneal sclerosis likely induced by peritoneal dialysis was unexpectedly observed in the livers of rats given bleomycin and lansoprazole. We examined whether this peritoneal thickening around the liver was time-dependently induced by administration of both drugs. Male Wistar rats were injected with bleomycin and/or lansoprazole for 2 or 4 weeks. The 3YB-1 cell line derived from rat fibroblasts was treated by bleomycin and/or lansoprazole for 24 h. The administration of both drugs together, but not individually, thickened the peritoneal tissue around the liver. There was accumulation of collagen fibers, macrophages, and eosinophils under mesothelial cells. Expressions of Col1a1, Mcp1 and Mcp3 genes were increased in the peritoneal tissue around the liver and in 3YB-1 cells by the administration of both drugs together, and Opn genes had increased expressions in this tissue and 3YB-1 cells. Mesothelial cells indicated immunoreactivity against both cytokeratin, a mesothelial cell marker, and αSMA, a fibroblast marker, around the livers of rats given both drugs. Administration of both drugs induced the migration of macrophages and eosinophils and induced fibrosis associated with the possible activation of fibroblasts and the possible promotion of the mesothelial-mesenchymal transition. This might become a novel model of peritoneal sclerosis for peritoneal dialysis.


Assuntos
Fibrose Peritoneal , Ratos , Masculino , Animais , Fibrose Peritoneal/induzido quimicamente , Fibrose Peritoneal/genética , Bleomicina/efeitos adversos , Ratos Wistar , Lansoprazol/efeitos adversos , Lansoprazol/metabolismo , Células Epiteliais/metabolismo , Peritônio/patologia
18.
Medicine (Baltimore) ; 102(45): e35343, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37960817

RESUMO

BACKGROUND: Lactobacillales including L mesenteroides have beneficial effects on human health, including improvement of psychological status and alleviation of allergic rhinitis. In mice, L mesenteroides subsp. strain NTM048 (NTM048) increased intestinal s-IgA. In humans, however, the effects of NTM048 on s-IgA secretion have been unclear. STUDY: This 16-week trial was performed using a double-blind, placebo-controlled, parallel group design. We aimed to establish whether Leuconostoc mesenteroides subsp. strain NTM048 increases the secretion of s-IgA in saliva. Forty healthy adults and forty patients with Japanese cedar pollinosis were recruited. Participants took either 2 test capsules including NTM048 (1010 CFU/day), or 2 placebo capsules per day, for 16 weeks. They were asked to collect their saliva and answered POMS2, a questionnaire about psychological status. The patients also answered questions about nasal symptoms. Blood samples were collected from the patients with Japanese Cedar pollinosis. Stool samples were collected at the start and on the last day of the trial. RESULTS: All subjects completed the trial. It was conducted during the season when Japanese cedar pollen is most scattered. Serum concentration of Japanese cedar pollen-specific IgE was > 2.0 UA/mL in patients with Japanese cedar pollinosis. The amount of s-IgA in saliva was not increased by NTM048 in overall subjects, and Japanese cedar pollen-specific IgE was not changed by NTM048 in patients with Japanese cedar pollinosis. The symptom of nasal blockage was improved by NTM048 12 weeks after the start of trial. post hoc analysis indicated a positive correlation between improving psychological status and the increase in occupation ratio of lactobacillus including NTM048. CONCLUSION: The amount of s-IgA in saliva was not increased by NTM048, but nasal blockage was improved by it. Psychological status might be improved if dosage of NTM048 is raised to the degree that NTM048 might be increased in the intestinal tract.


Assuntos
Leuconostoc mesenteroides , Obstrução Nasal , Rinite Alérgica Sazonal , Adulto , Humanos , Animais , Camundongos , Rinite Alérgica Sazonal/tratamento farmacológico , Japão , Imunoglobulina E , Imunoglobulina A/uso terapêutico
19.
PNAS Nexus ; 2(11): pgad351, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37954160

RESUMO

The endoplasmic reticulum (ER)-embedded transcription factors, sterol regulatory element-binding proteins (SREBPs), master regulators of lipid biosynthesis, are transported to the Golgi for proteolytic activation to tune cellular cholesterol levels and regulate lipogenesis. However, mechanisms by which the cell responds to the levels of saturated or unsaturated fatty acids remain underexplored. Here, we show that RHBDL4/RHBDD1, a rhomboid family protease, directly cleaves SREBP-1c at the ER. The p97/VCP, AAA-ATPase complex then acts as an auxiliary segregase to extract the remaining ER-embedded fragment of SREBP-1c. Importantly, the enzymatic activity of RHBDL4 is enhanced by saturated fatty acids (SFAs) but inhibited by polyunsaturated fatty acids (PUFAs). Genetic deletion of RHBDL4 in mice fed on a Western diet enriched in SFAs and cholesterol prevented SREBP-1c from inducing genes for lipogenesis, particularly for synthesis and incorporation of PUFAs, and secretion of lipoproteins. The RHBDL4-SREBP-1c pathway reveals a regulatory system for monitoring fatty acid composition and maintaining cellular lipid homeostasis.

20.
Circulation ; 148(21): 1691-1704, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37850394

RESUMO

BACKGROUND: Hypercontractility and arrhythmia are key pathophysiologic features of hypertrophic cardiomyopathy (HCM), the most common inherited heart disease. ß-Adrenergic receptor antagonists (ß-blockers) are the first-line therapy for HCM. However, ß-blockers commonly selected for this disease are often poorly tolerated in patients, where heart-rate reduction and noncardiac effects can lead to reduced cardiac output and fatigue. Mavacamten, myosin ATPase inhibitor recently approved by the US Food and Drug Administration, has demonstrated the ability to ameliorate hypercontractility without lowering heart rate, but its benefits are so far limited to patients with left ventricular (LV) outflow tract obstruction, and its effect on arrhythmia is unknown. METHODS: We screened 21 ß-blockers for their impact on myocyte contractility and evaluated the antiarrhythmic properties of the most promising drug in a ventricular myocyte arrhythmia model. We then examined its in vivo effect on LV function by hemodynamic pressure-volume loop analysis. The efficacy of the drug was tested in vitro and in vivo compared with current therapeutic options (metoprolol, verapamil, and mavacamten) for HCM in an established mouse model of HCM (Myh6R403Q/+ and induced pluripotent stem cell (iPSC)-derived cardiomyocytes from patients with HCM (MYH7R403Q/+). RESULTS: We identified that carvedilol, a ß-blocker not commonly used in HCM, suppresses contractile function and arrhythmia by inhibiting RyR2 (ryanodine receptor type 2). Unlike metoprolol (a ß1-blocker), carvedilol markedly reduced LV contractility through RyR2 inhibition, while maintaining stroke volume through α1-adrenergic receptor inhibition in vivo. Clinically available carvedilol is a racemic mixture, and the R-enantiomer, devoid of ß-blocking effect, retains the ability to inhibit both α1-receptor and RyR2, thereby suppressing contractile function and arrhythmias without lowering heart rate and cardiac output. In Myh6R403Q/+ mice, R-carvedilol normalized hyperdynamic contraction, suppressed arrhythmia, and increased cardiac output better than metoprolol, verapamil, and mavacamten. The ability of R-carvedilol to suppress contractile function was well retained in MYH7R403Q/+ iPSC-derived cardiomyocytes. CONCLUSIONS: R-enantiomer carvedilol attenuates hyperdynamic contraction, suppresses arrhythmia, and at the same time, improves cardiac output without lowering heart rate by dual blockade of α1-adrenergic receptor and RyR2 in mouse and human models of HCM. This combination of therapeutic effects is unique among current therapeutic options for HCM and may particularly benefit patients without LV outflow tract obstruction.


Assuntos
Cardiomiopatia Hipertrófica , Metoprolol , Humanos , Camundongos , Animais , Carvedilol/farmacologia , Carvedilol/uso terapêutico , Metoprolol/uso terapêutico , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Cardiomiopatia Hipertrófica/complicações , Cardiomiopatia Hipertrófica/tratamento farmacológico , Arritmias Cardíacas/tratamento farmacológico , Arritmias Cardíacas/metabolismo , Antagonistas Adrenérgicos beta/farmacologia , Antagonistas Adrenérgicos beta/uso terapêutico , Miócitos Cardíacos/metabolismo , Verapamil/uso terapêutico , Receptores Adrenérgicos/metabolismo
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