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1.
J Neurogastroenterol Motil ; 30(2): 220-228, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38576371

RESUMO

Background/Aims: Drugs that stabilize intestinal motility may improve the efficacy of nonabsorbable antibiotics, such as rifaximin, against small intestinal bacterial overgrowth (SIBO). We compared the efficacy of rifaximin alone with that of its combination with trimebutine maleate against SIBO. Methods: We performed a randomized double-blind placebo-controlled trial (https://cris.nih.go.kr, no. KCT0004836) that included patients with functional bloating, no constipation, and SIBO using the hydrogen (H2)-methane (CH4) glucose breath test (GBT). Patients were randomized into 2 groups in a 1:1 ratio, namely rifaximin (1200 mg/day) + trimebutine maleate (600 mg/day) group and rifaximin + placebo group, for 2 weeks. Patients completed a symptom questionnaire and underwent a GBT at baseline and at 1 month after treatment withdrawal. The primary outcome was SIBO eradication. The secondary outcomes included changes in the concentrations of exhaled gases, symptoms, and presence of adverse events. Results: The complete eradication rate of SIBO was 35.9% (14/39) in the rifaximin group, and 34.1% (14/41) in the combined group with no significant differences. In both groups, no significant differences were observed in GBT profiles before and after the treatment, respectively. However total breath H2 and CH4 concentration were conspicuously decreased in the combined group after treatment. The combined group exhibited substantial relief of bloating. The adverse events were similar in the 2 groups. Conclusion: While the combination therapy was not superior over rifaximin alone for SIBO eradication, it improves the symptom of bloating with numerically reducing the concentration of breath H2/CH4.

2.
J Enzyme Inhib Med Chem ; 39(1): 2343350, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38655602

RESUMO

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death. FGFR4 has been implicated in HCC progression, making it a promising therapeutic target. We introduce an approach for identifying novel FGFR4 inhibitors by sequentially adding fragments to a common warhead unit. This strategy resulted in the discovery of a potent inhibitor, 4c, with an IC50 of 33 nM and high selectivity among members of the FGFR family. Although further optimisation is required, our approach demonstrated the potential for discovering potent FGFR4 inhibitors for HCC treatment, and provides a useful method for obtaining hit compounds from small fragments.


Assuntos
Relação Dose-Resposta a Droga , Descoberta de Drogas , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/metabolismo , Humanos , Relação Estrutura-Atividade , Estrutura Molecular , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo
3.
Scand J Gastroenterol ; : 1-7, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587111

RESUMO

OBJECTIVES: While endoscopic resection of rectal neuroendocrine tumors (NETs) has significantly increased, long-term data on risk factors for recurrence are still lacking. Our aim is to analyze the long-term outcomes of patients with rectal NETs after endoscopic resection through risk stratification. METHODS: In this multicenter retrospective study, we included patients who underwent endoscopic resection of rectal NETs from 2009 to 2018 and were followed for ≥12 months at five university hospitals. We classified the patients into three risk groups according to the clinicopathological status of the rectal neuroendocrine tumors: low, indeterminate, and high. The high-risk group was defined if the tumors have any of the followings: size ≥ 10 mm, lymphovascular invasion, muscularis propria or deeper invasion, positive resection margins, or mitotic count ≥2/10. RESULTS: A total of 346 patients were included, with 144 (41.6%), 121 (35.0%), and 81 (23.4%) classified into the low-, indeterminate-, and high-risk groups, respectively. Among the high-risk group, seven patients (8.6%) received salvage treatment 28 (27-67) days after the initial endoscopic resection, with no reported extracolonic recurrence. Throughout the follow-up period, 1.1% (4/346) of patients experienced extracolonic recurrences at 56.5 (54-73) months after the initial endoscopic resection. Three of these patients (75%) were in the high-risk group and did not undergo salvage treatment. The risk of extracolonic recurrence was significantly higher in the high-risk group compared to the other groups (p = 0.039). CONCLUSION: Physicians should be concerned about the possibility of metastasis during long-term follow-up of high-risk patients and consider salvage treatment.

4.
iScience ; 27(1): 108657, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38205250

RESUMO

Although countless gut microbiome studies on colitis using mouse models have been carried out, experiments with small sample sizes have encountered reproducibility limitations because of batch effects and statistical errors. In this study, dextran-sodium-sulfate-induced microbial dysbiosis index (DiMDI) was introduced as a reliable dysbiosis index that can be used to assess the state of microbial dysbiosis in DSS-induced mouse models. Meta-analysis of 189 datasets from 11 independent studies was performed to construct the DiMDI. Microbial dysbiosis biomarkers, Muribaculaceae, Alistipes, Turicibacter, and Bacteroides, were selected through four different feature selection methods and used to construct the DiMDI. This index demonstrated a high accuracy of 82.3% and showed strong robustness (88.9%) in the independent cohort. Therefore, DiMDI may be used as a standard for assessing microbial imbalance in DSS-induced mouse models and may contribute to the development of reliable colitis microbiome studies in mouse experiments.

5.
Cell ; 187(1): 95-109.e26, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38181745

RESUMO

DddA-derived cytosine base editors (DdCBEs) and transcription activator-like effector (TALE)-linked deaminases (TALEDs) catalyze targeted base editing of mitochondrial DNA (mtDNA) in eukaryotic cells, a method useful for modeling of mitochondrial genetic disorders and developing novel therapeutic modalities. Here, we report that A-to-G-editing TALEDs but not C-to-T-editing DdCBEs induce tens of thousands of transcriptome-wide off-target edits in human cells. To avoid these unwanted RNA edits, we engineered the substrate-binding site in TadA8e, the deoxy-adenine deaminase in TALEDs, and created TALED variants with fine-tuned deaminase activity. Our engineered TALED variants not only reduced RNA off-target edits by >99% but also minimized off-target mtDNA mutations and bystander edits at a target site. Unlike wild-type versions, our TALED variants were not cytotoxic and did not cause developmental arrest of mouse embryos. As a result, we obtained mice with pathogenic mtDNA mutations, associated with Leigh syndrome, which showed reduced heart rates.


Assuntos
DNA Mitocondrial , Efetores Semelhantes a Ativadores de Transcrição , Animais , Humanos , Camundongos , Adenina , Citosina , DNA Mitocondrial/genética , Edição de Genes , RNA , Efetores Semelhantes a Ativadores de Transcrição/metabolismo , Engenharia de Proteínas
6.
Cancer Sci ; 115(3): 989-1000, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38226451

RESUMO

Chemotherapy combined with debulking surgery is the standard treatment protocol for high-grade serous ovarian carcinoma (HGSOC). Nonetheless, a significant number of patients encounter relapse due to the development of chemotherapy resistance. To better understand and address this resistance, we conducted a comprehensive study investigating the transcriptional alterations at the single-cell resolution in tissue samples from patients with HGSOC, using single-cell RNA sequencing and T-cell receptor sequencing techniques. Our analyses unveiled notable changes in the tumor signatures after chemotherapy, including those associated with epithelial-mesenchymal transition and cell cycle arrest. Within the immune compartment, we observed alterations in the T-cell profiles, characterized by naïve or pre-exhausted populations following chemotherapy. This phenotypic change was further supported by the examination of adjoining T-cell receptor clonotypes in paired longitudinal samples. These findings underscore the profound impact of chemotherapy on reshaping the tumor landscape and the immune microenvironment. This knowledge may provide clues for the development of future therapeutic strategies to combat treatment resistance in HGSOC.


Assuntos
Neoplasias Ovarianas , Feminino , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Linfócitos T/patologia , Receptores de Antígenos de Linfócitos T , Microambiente Tumoral
7.
J Prosthet Dent ; 131(1): 166.e1-166.e9, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37945512

RESUMO

STATEMENT OF PROBLEM: Improvement in the mechanical properties of 3-dimensional (3D) printed dental prostheses is necessary to prevent wear caused by an antagonist or fracture. However, how different printing temperatures affect their mechanical properties is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the mechanical properties of 3D printed parts fabricated at different printing temperatures. MATERIAL AND METHODS: Photopolymer specimens were fabricated at 3 different temperatures (room temperature, 50 °C, and 70 °C) using a stereolithography 3D printer. After rinsing to remove the residual monomer, the specimens were divided into 2 groups: with or without postprocessing. The viscosity of the photopolymerization resin was measured while the temperature was increased. Furthermore, the double-bond conversion (DBC) of the printed part was evaluated (n=3). Mechanical properties were investigated via dynamic mechanical analysis (n=1) and tensile testing (n=5). Statistical comparisons were performed via 1-way analysis of variance, followed by the Tukey honestly significant difference test (α=.05). RESULTS: The DBC rates of the green condition group increased from 66.67% to 86.33% with increasing temperature. In addition, these specimens exhibited improved mechanical properties and reduced residual monomer levels. CONCLUSIONS: Specimens fabricated at a temperature of 70 °C exhibited mechanical properties suitable for clinical application.


Assuntos
Impressão Tridimensional , Estereolitografia , Temperatura , Polimerização , Teste de Materiais , Propriedades de Superfície
8.
J Prosthet Dent ; 131(2): 330.e1-330.e9, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37993321

RESUMO

STATEMENT OF PROBLEM: Prostheses printed on a 3-dimensional (3D) printer need to undergo the postpolymerization process, which can increase the working time. However, it has been not suggested for reducing workload and improving the properties of prostheses in dental clinical practice. PURPOSE: The purpose of this in vitro study was to evaluate how the printing temperature impacts the dimensional accuracy and fracture load of 3D printed fixed dental prostheses (FDPs). MATERIAL AND METHODS: Dental prostheses were printed at room temperature (RT), 50°C, and 70°C using a stereolithography 3D printer. Subsequently, after rinsing away residual monomer, the printed parts underwent the green condition (it was not subjected to any postprocessing) and postpolymerization. The mechanical properties of the printed FDPs were determined by loading to fracture (n=6). To evaluate their clinical applicability, the dimensional accuracy and fit of FDPs fabricated at various resin polymerization temperatures were measured (n=6). The 1-way analysis of variance was used to perform statistical comparisons, followed by the Tukey honestly significant difference test (α=.05). RESULTS: The specimens printed at RT and 50°C were better than those printed at 70°C in terms of dimensional accuracy and fit (P<.05). Nonetheless, the dimensional accuracy and fit of the specimens printed at 70°C were clinically acceptable. The fracture load of the 3-unit FDPs depended significantly on the printing temperature. CONCLUSIONS: The dimensional accuracy and fracture load of the 70°C group were acceptable for FDP fabrication. Thus, the temperature of 70°C without postprocessing may help make the procedure more efficient.


Assuntos
Prótese Dentária , Estereolitografia , Temperatura , Desenho Assistido por Computador , Polimerização , Teste de Materiais , Impressão Tridimensional
9.
Sci Rep ; 13(1): 21661, 2023 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-38066236

RESUMO

This clinical study aimed to predict the learning curve of wireless and wired intraoral scanners (IOSs) and to compare the reduction patterns of working time. Overall, 14 participants were enrolled in the study. The intraoral scanning procedure was repeated four times, each using wireless and wired IOSs (i700; MEDIT). The work time from the first to the 600th iterations was predicted using the Wright model. Regarding statistical analysis, the Mann-Whitney U-test was performed for comparison between wireless and wired IOSs and between groups with and without an IOS usage experience, and the Friedman test was performed to evaluate the time reduction (α = 0.05). There was a significant difference between wireless and wired IOSs in the first (P = 0.008) and the third (P = 0.035) iterations. Moreover, the time for 600 iterations was statistically significantly different between wireless and wired IOSs (P < 0.05); however, there was no significant difference after the sixth iteration (e.g., seventh iteration: P = 0.062). In wireless IOS, no significant difference was found between participants with and without an IOS usage experience after the 34th iteration (P = 0.053). The difference in the learning effect between wireless and wired IOSs can be overcome by initial learning; however, an IOS usage experience can affect the learning time of wireless IOSs.


Assuntos
Imageamento Tridimensional , Curva de Aprendizado , Humanos , Desenho Assistido por Computador , Modelos Dentários , Estatísticas não Paramétricas
10.
Int J Mol Sci ; 24(24)2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38139137

RESUMO

Agrimonia pilosa Ledeb., an important medicinal herb in traditional East Asian medicine, is primarily used to treat abdominal pain, dysentery, and hemostasis. There are ten other reported species of Agrimonia plants, including Agrimonia coreana Nakai-a naturally growing species in South Korea-and Agrimonia eupatoria Linn. Although recent studies have isolated numerous active constituents and investigated their effects, the medicinal utility of this herb is not yet fully explored. Through patch-clamp recording, a previous study reported that Agrimonia plant extracts inhibit the function of Ca2+ release-activated Ca2+ channels (CRACs). Herein, we aimed to identify and isolate the main compounds in A. coreana responsible for CRAC inhibition while assessing the anti-inflammatory effects mediated by this inhibition. We demonstrated for the first time that alphitolic acid isolated from A. coreana has a dose-dependent inhibitory effect on CRAC activity and, thus, an inhibitory effect on intracellular calcium increase. Furthermore, analysis of human CD4+ T cell proliferation via the carboxyfluorescein diacetate succinimidyl ester method revealed that alphitolic acid inhibited T cell proliferation in a concentration-dependent manner. Our findings provide a theoretical basis for the potential therapeutic use of alphitolic acid in the treatment of inflammatory diseases.


Assuntos
Agrimonia , Humanos , Linfócitos T , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Anti-Inflamatórios/farmacologia
11.
Membranes (Basel) ; 13(12)2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38132892

RESUMO

In this study, the optimal fabrication parameters of a heterogeneous anion-exchange membrane (AEM) using an ionomer binder are investigated to improve the performance of continuous electrodeionization (CEDI) for producing ultrapure water. Poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) is selected as the base material for preparing the ionomer binder and quaternized to have various ion exchange capacities (IECs). The optimal content of ion-exchange resin (IER) powder according to the IEC of the ionomer binder is then determined through systematic analyses. In conclusion, it is revealed that a heterogeneous AEM with optimal performance can be fabricated when the IEC of the ionomer binder is lowered and the content of IER powder is also lower than that of conventional heterogeneous membranes. Moreover, crosslinked quaternized PPO (QPPO) nanofiber powder is used as an additive to improve ion conductivity without deteriorating the mechanical properties of the membrane. The membrane fabricated under optimal conditions exhibits significantly lower electrical resistance (4.6 Ω cm2) despite a low IER content (30 wt%) compared to the commercial membrane (IONAC MA-3475, 13.6 Ω cm2) while also demonstrating moderate tensile strength (9.7 MPa) and a high transport number (ca. 0.97). Furthermore, it is proven that the prepared membrane exhibits a superior ion removal rate (99.86%) and lower energy consumption (0.35 kWh) compared to the commercial membrane (99.76% and 0.4 kWh, respectively) in CEDI experiments.

12.
Int J Prosthodont ; 0(0): 1-16, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37988424

RESUMO

PURPOSE: This study aimed to evaluate the effects of an ergonomic dentist stool design on muscle activity and fatigue in dentists. MATERIALS AND METHODS: Fourteen dentists were recruited, and electrodes were attached to the arm, neck, and shoulder muscles of these dentists according to the Surface ElectroMyoGraphy for the Non-Invasive Assessment of Muscles protocol. After measuring the maximal voluntary contraction, eight-channel surface electromyography was performed during simulations of two dental procedures (intraoral scanning and tooth preparation) while the dentists were using two types of dentist stools. Furthermore, muscle activity and fatigue were determined based on the eight-channel surface electromyography data, and ergonomic risk levels were evaluated according to the muscle activity. The Shapiro-Wilk test was used to confirm that all data were normally distributed, and the Mann-Whitney U test was used to compare the two types of dentist stools (α = 0.05). RESULTS: There was a significant difference between the conventional and ergonomically designed dentist stools in terms of the activity of trapezius descendens muscle (p < 0.05). Notably, the activity of the trapezius descendens muscle was lesser when the dentists used ergonomically designed dentist stools than when they used a conventional dentist stool. The activity of all muscles, except for the sternocleidomastoid, indicated moderate ergonomic risk. CONCLUSION: A dentist stool that enables dentists to maintain ergonomic posture should be used to prevent musculoskeletal disorders.

13.
Cancers (Basel) ; 15(20)2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37894424

RESUMO

The role of upfront primary tumor resection (PTR) in patients with unresectable metastatic colorectal cancer without severe symptoms remains controversial. We retrospectively analyzed the role of PTR in overall survival (OS) in this population. Among the 205 patients who enrolled, the PTR group (n = 42) showed better performance (p = 0.061), had higher frequencies of right-sided origin (p = 0.058), the T4 stage (p = 0.003), the M1a stage (p = 0.012), and <2 organ metastases (p = 0.002), and received fewer targeted agents (p = 0.011) than the chemotherapy group (n = 163). The PTR group showed a trend for longer OS (20.5 versus 16.0 months, p = 0.064) but was not related to OS in Cox regression multivariate analysis (p = 0.220). The male sex (p = 0.061), a good performance status (p = 0.078), the T3 stage (p = 0.060), the M1a stage (p = 0.042), <2 organ metastases (p = 0.035), an RAS wild tumor (p = 0.054), and the administration of targeted agents (p = 0.037), especially bevacizumab (p = 0.067), seemed to be related to PTR benefits. Upfront PTR could be considered beneficial in some subgroups, but these findings require larger studies to verify.

14.
J Korean Med Sci ; 38(35): e275, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37667580

RESUMO

BACKGROUND: Fracture risks and associated factors are poorly understood in middle-aged and older Asian populations with inflammatory bowel disease (IBD). Therefore, we investigated fracture risk and the effects of comorbidities and lifestyle habits on the risk of developing fractures in middle-aged and older Korean patients with IBD. METHODS: We conducted a nationwide population-based cohort study using data from the National Health Insurance Corporation Database. Patients with IBD who underwent the National Screening Program and were over 40 years of age were included in the study. We compared patients with age- and sex-matched controls. The incidence of fractures, including vertebral, hip, and other sites, was determined using claims data. RESULTS: The risk of total fractures and vertebral fractures was significantly higher in the IBD group (adjusted hazard ratio [HR], 1.31, 95% confidence interval [CI], 1.16-1.48; adjusted HR, 1.59, 95% CI, 1.33-1.92, respectively). Obesity, diabetes, hypertension, and lack of exercise were associated with increased fracture risk in patients with ulcerative colitis (UC). In contrast, the risk increases in patients with Crohn's disease regardless of comorbidities and lifestyle preferences. CONCLUSION: The risk of bone fracture, especially vertebral fracture, is high in middle-aged and older Korean patients with IBD. Obesity, diabetes, hypertension, and lack of exercise are all risk factors associated with bone fractures in patients with UC. These findings are helpful for clinicians to educate patients with IBD on bone health and raise awareness of bone fractures in patients with UC who have specific risk factors.


Assuntos
Colite Ulcerativa , Fraturas Ósseas , Hipertensão , Doenças Inflamatórias Intestinais , Fraturas da Coluna Vertebral , Pessoa de Meia-Idade , Humanos , Idoso , Adulto , Estudos de Coortes , Doenças Inflamatórias Intestinais/complicações , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/etiologia , Colite Ulcerativa/complicações , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/etiologia , Obesidade , República da Coreia/epidemiologia
15.
Brain Tumor Res Treat ; 11(3): 191-203, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37550819

RESUMO

BACKGROUND: Inflammasomes are key in the initiation of inflammatory responses and serve to defend the organism. However, when the immune system is imbalanced, these complexes contribute to tumor progression. The purpose of this study was to investigate the effect of non-canonical inflammasomes on glioma malignancy. METHODS: We performed bioinformatics analysis to confirm the expression of canonical and non-canonical inflammasome-related molecules according to the degree of malignancy through immunohistochemical examination of glioma tissues obtained with patient consent from our institution. RESULTS: Bioinformatics analysis confirmed that the expression levels of non-canonical inflammasome-related molecules were significantly higher in tumor tissues than in normal tissues, and they also increased according to malignancy, which adversely affected the survival rate. Furthermore, in gliomas, positive correlations were found between N-form gasdermin-D, a key molecule associated with the non-canonical inflammasome, and other related molecules, including NLRP3, caspase-1, caspase-4, and caspase-5. These results were verified by immunohistochemical examination of glioma tissues, and the expression levels of these molecules also increased significantly with increasing grade. In addition, the features of pyroptosis were confirmed. CONCLUSION: This study identified the potential of non-canonical inflammasomes as aggressiveness markers for gliomas and presented a perspective for improving glioma treatment.

16.
Kidney Int ; 104(4): 724-739, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37399974

RESUMO

Ischemia-reperfusion (IR) injury, a leading cause of acute kidney injury (AKI), is still without effective therapies. Succinate accumulation during ischemia followed by its oxidation during reperfusion leads to excessive reactive oxygen species (ROS) and severe kidney damage. Consequently, the targeting of succinate accumulation may represent a rational approach to the prevention of IR-induced kidney injury. Since ROS are generated primarily in mitochondria, which are abundant in the proximal tubule of the kidney, we explored the role of pyruvate dehydrogenase kinase 4 (PDK4), a mitochondrial enzyme, in IR-induced kidney injury using proximal tubule cell-specific Pdk4 knockout (Pdk4ptKO) mice. Knockout or pharmacological inhibition of PDK4 ameliorated IR-induced kidney damage. Succinate accumulation during ischemia, which is responsible for mitochondrial ROS production during reperfusion, was reduced by PDK4 inhibition. PDK4 deficiency established conditions prior to ischemia resulting in less succinate accumulation, possibly because of a reduction in electron flow reversal in complex II, which provides electrons for the reduction of fumarate to succinate by succinate dehydrogenase during ischemia. The administration of dimethyl succinate, a cell-permeable form of succinate, attenuated the beneficial effects of PDK4 deficiency, suggesting that the kidney-protective effect is succinate-dependent. Finally, genetic or pharmacological inhibition of PDK4 prevented IR-induced mitochondrial damage in mice and normalized mitochondrial function in an in vitro model of IR injury. Thus, inhibition of PDK4 represents a novel means of preventing IR-induced kidney injury, and involves the inhibition of ROS-induced kidney toxicity through reduction in succinate accumulation and mitochondrial dysfunction.


Assuntos
Traumatismo por Reperfusão , Ácido Succínico , Camundongos , Animais , Ácido Succínico/farmacologia , Espécies Reativas de Oxigênio , Camundongos Knockout , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle , Isquemia/tratamento farmacológico , Rim , Mitocôndrias , Reperfusão
17.
Mol Cells ; 46(8): 476-485, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37460253

RESUMO

Gastric cancer stem-like cells (GCSCs) possess stem cell properties, such as self-renewal and tumorigenicity, which are known to induce high chemoresistance and metastasis. These characteristics of GCSCs are further enhanced by autophagy, worsening the prognosis of patients. Currently, the mechanisms involved in the induction of stemness in GCSCs during autophagy remain unclear. In this study, we compared the cellular responses of GCSCs with those of gastric cancer intestinal cells (GCICs) whose stemness is not induced by autophagy. In response to glucose starvation, the levels of ß-catenin and stemness-related genes were upregulated in GCSCs, while the levels of ß-catenin declined in GCICs. The pattern of deubiquitinase ubiquitin C-terminal hydrolase-L3 (UCH-L3) expression in GCSCs and GCICs was similar to that of ß-catenin expression depending on glucose deprivation. We also observed that inhibition of UCH-L3 activity reduced ß-catenin protein levels. The interaction between UCH-L3 and ß-catenin proteins was confirmed, and it reduced the ubiquitination of ß-catenin. Our results suggest that UCH-L3 induces the stabilization of ß-catenin, which is required to promote stemness during autophagy activation. Also, UCH-L3 expression was regulated by c-Fos, and the levels of c-Fos increased in response to autophagy activation. In summary, our findings suggest that the inhibition of UCH-L3 during nutrient deprivation could suppress stress resistance of GCSCs and increase the survival rates of gastric cancer patients.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , beta Catenina/metabolismo , Células-Tronco Neoplásicas/metabolismo , Ubiquitinação
18.
BMB Rep ; 56(11): 600-605, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37401237

RESUMO

Intrahepatic cholangiocarcinoma (ICC) is a bile duct cancer and a rare malignant tumor with a poor prognosis owing to the lack of an early diagnosis and resistance to conventional chemotherapy. A combination of gemcitabine and cisplatin is the typically attempted first-line treatment approach. However, the underlying mechanism of resistance to chemotherapy is poorly understood. We addressed this by studying dynamics in the human ICC SCK cell line. Here, we report that the regulation of glucose and glutamine metabolism was a key factor in overcoming cisplatin resistance in SCK cells. RNA sequencing analysis revealed a high enrichment cell cycle-related gene set score in cisplatin-resistant SCK (SCK-R) cells compared to parental SCK (SCK WT) cells. Cell cycle progression correlates with increased nutrient requirement and cancer proliferation or metastasis. Commonly, cancer cells are dependent upon glucose and glutamine availability for survival and proliferation. Indeed, we observed the increased expression of GLUT (glucose transporter), ASCT2 (glutamine transporter), and cancer progression markers in SCK-R cells. Thus, we inhibited enhanced metabolic reprogramming in SCK-R cells through nutrient starvation. SCK-R cells were sensitized to cisplatin, especially under glucose starvation. Glutaminase-1 (GLS1), which is a mitochondrial enzyme involved in tumorigenesis and progression in cancer cells, was upregulated in SCK-R cells. Targeting GLS1 with the GLS1 inhibitor CB-839 (telaglenastat) effectively reduced the expression of cancer progression markers. Taken together, our study results suggest that a combination of GLUT inhibition, which mimics glucose starvation, and GLS1 inhibition could be a therapeutic strategy to increase the chemosensitivity of ICC. [BMB Reports 2023; 56(11): 600-605].


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Glutamina/metabolismo , Glucose/metabolismo , Proliferação de Células , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/genética , Colangiocarcinoma/metabolismo , Linhagem Celular Tumoral , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/tratamento farmacológico
19.
Biol Direct ; 18(1): 32, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322541

RESUMO

Adipose tissue, an organ critical for systemic energy homeostasis, is influenced by type 2 immunity in its development and function. The type 2 cytokine interleukin (IL)-4 induces the proliferation of bipotential adipocyte precursors (APs) in white fat tissue and primes these cells for differentiation into beige adipocytes, which are specialized for thermogenesis. However, the underlying mechanisms have not yet been comprehensively examined. Here, we identified six microRNA (miRNA) genes upregulated upon IL-4 stimulation in APs, miR-322, miR-503, miR-351, miR-542, miR-450a, and miR-450b; these are encoded in the H19X locus of the genome. Their expression is positively regulated by the transcription factor Klf4, whose expression also increases upon IL-4 stimulation. These miRNAs shared a large set of target genes, of which 381 genes were downregulated in mRNA expression upon IL-4 stimulation and enriched in Wnt signaling pathways. Two genes with downregulated expression, Ccnd1 and Fzd6, were repressed by H19X-encoded miRNAs. Additionally, the Wnt signaling activator LiCl downregulated the expression of this group of miRNAs in APs, indicating that Wnt signaling-related genes and these miRNAs form a double-negative feedback regulatory loop. This miRNA/Wnt feedback regulation modulated the elevated proliferation of APs induced by IL-4 stimulation and contributed to priming them for beige adipocyte differentiation. Moreover, the aberrant expression of these miRNAs attenuates the differentiation of APs into beige adipocytes. Collectively, our results suggest that H19X-encoded miRNAs facilitate the transition of APs from proliferation to differentiation in the IL-4-mediated regulation.


Assuntos
MicroRNAs , MicroRNAs/genética , MicroRNAs/metabolismo , Interleucina-4/metabolismo , Diferenciação Celular/genética , Adipócitos/metabolismo , Proliferação de Células
20.
Medicine (Baltimore) ; 102(19): e33790, 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37171320

RESUMO

INTRODUCTION: Collateral circulation sustains cerebral perfusion in patients with arterial occlusion. Extensive arterial occlusion may redirect cerebral blood flow to compensate for insufficient perfusion. Cerebral artery occlusion can be observed in computed tomography perfusion imaging with increased mean transit time (MTT). However, in some cases, MTT delay occurs contralateral to the site of stenosis or occlusion. This delay cannot be explained simply by the collateral blood supply. Therefore, the authors considered the similarity of the perfusion delay observed at the normal site to that observed in subclavian steal syndrome. CASE PRESENTATION: Three patients were reviewed: the first had severe stenosis in the left proximal internal carotid artery (ICA), and the second had left common carotid artery occlusion and diffusion restriction of the ICA-middle carotid artery border zone. The third patient had total occlusion of the left common carotid artery and right proximal ICA, with multifocal infarctions in the right frontal, occipital, left frontal, and parietal lobes. All 3 patients had a contralateral MTT delay on perfusion imaging. CONCLUSION: The site of stenosis or occlusion did not correlate with ipsilateral perfusion delay in these 3 cases. Based on the precedent relationship between infarction and perfusion delay, we developed 2 hypotheses to explain why perfusion decreases on the contralateral side of the occlusion or stenosis. However, this study was limited because we could not identify events, like volume loss or decreased blood pressure, before stroke development.


Assuntos
Estenose das Carótidas , AVC Isquêmico , Humanos , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Constrição Patológica , Artéria Carótida Interna/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Perfusão , Circulação Cerebrovascular/fisiologia
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