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1.
J Mol Biol ; 436(10): 168575, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38641238

RESUMEN

DNA mismatch repair endonuclease MutL is a member of GHKL ATPase superfamily. Mutations of MutL homologs are causative of a hereditary cancer, Lynch syndrome. We characterized MutL homologs from human and a hyperthermophile, Aquifex aeolicus, (aqMutL) to reveal the catalytic mechanism for the ATPase activity. Although involvement of a basic residue had not been conceived in the catalytic mechanism, analysis of the pH dependence of the aqMutL ATPase activity revealed that the reaction is catalyzed by a residue with an alkaline pKa. Analyses of mutant aqMutLs showed that Lys79 is the catalytic residue, and the corresponding residues were confirmed to be critical for activities of human MutL homologs, on the basis of which a catalytic mechanism for MutL ATPase is proposed. These and other results described here would contribute to evaluating the pathogenicity of Lynch syndrome-associated missense mutations. Furthermore, it was confirmed that the catalytic lysine residue is conserved among DNA gyrases and microrchidia ATPases, other members of GHKL ATPases, indicating that the catalytic mechanism proposed here is applicable to these members of the superfamily.


Asunto(s)
Adenosina Trifosfatasas , Lisina , Lisina/metabolismo , Lisina/genética , Humanos , Adenosina Trifosfatasas/genética , Adenosina Trifosfatasas/metabolismo , Adenosina Trifosfatasas/química , Proteínas MutL/genética , Proteínas MutL/metabolismo , Proteínas MutL/química , Dominio Catalítico , Secuencia de Aminoácidos , Secuencia Conservada , Concentración de Iones de Hidrógeno , Catálisis , Factores de Transcripción
2.
Gastrointest Endosc ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38631519

RESUMEN

BACKGROUND AND AIMS: The difficulty of radiographic confirmation of the presence of stones remains a challenge in the treatment of intrahepatic bile duct (IHBD) stones in patients after hepaticojejunostomy (HJ). Peroral direct cholangioscopy (PDCS) enables direct observation of the bile duct and is useful for detecting and removing residual stones; however, its effectiveness is not clearly established in this clinical context. METHODS: This single-center, single-arm, prospective study included 44 patients with IHBD who underwent bowel reconstruction with HJ during the study period. Stone removal was performed by short-type double-balloon enteroscopy (DBE). Following balloon-occluded cholangiography, the DBE was exchanged for an ultraslim endoscope through the balloon overtube for PDCS. The primary endpoint was the rate of residual stones detected by PDCS. Secondary endpoints were success rate of PDCS, residual stone removal with PDCS, procedure time for PDCS, procedure-related adverse events, and stone recurrence rate. RESULTS: PDCS was successful in 39/44 patients (89%), among whom residual stones were detected in 16 (41%) (95% CI: 28%-54%). Twelve patients (75%) had residual stones <5 mm. Stone removal was successful in 15 (94%) patients and median procedure time for PDCS was 16 (IQR: 10-26) min. The rate of procedure-related adverse events was 7% (3/44), all of which improved with conservative treatment. During median follow-up of 2.1 years (IQR: 1.4-3.3), the overall probability of recurrence-free status at 1, 2, and 3 years was 100%, 92%, and 86%, respectively. CONCLUSIONS: PDCS is a safe and effective procedure for complete stone removal in patients with IHBD stones after HJ.

3.
Mol Ther Oncol ; 32(1): 200765, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38596294

RESUMEN

Gallbladder cancer incidence has been increasing globally, and it remains challenging to expect long prognosis with the current systemic chemotherapy. We identified a novel nucleic acid-mediated therapeutic target against gallbladder cancer by using innovative organoid-based gallbladder cancer models generated from KrasLSL-G12D/+; Trp53f/f mice. Using comprehensive microRNA expression analyses and a bioinformatics approach, we identified significant microRNA-34a-5p downregulation in both murine gallbladder cancer organoids and resected human gallbladder cancer specimens. In three different human gallbladder cancer cell lines, forced microRNA-34a-5p expression inhibited cell proliferation and induced cell-cycle arrest at the G1 phase by suppressing direct target (CDK6) expression. Furthermore, comprehensive RNA sequencing revealed the significant enrichment of gene sets related to the cell-cycle regulators after microRNA-34a-5p expression in gallbladder cancer cells. In a murine xenograft model, locally injected microRNA-34a-5p mimics significantly inhibited gallbladder cancer progression and downregulated CDK6 expression. These results provide a rationale for promising therapeutics against gallbladder cancer by microRNA-34a-5p injection, as well as a strategy to explore therapeutic targets against cancers using organoid-based models, especially for those lacking useful genetically engineered murine models, such as gallbladder cancer.

4.
J Mol Biol ; 436(6): 168461, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38301805

RESUMEN

Early phase of amyloid formation, where prefibrillar aggregates such as oligomers and protofibrils are often observed, is crucial for understanding pathogenesis. However, the detailed mechanisms of their formation have been difficult to elucidate because they tend to form transiently and heterogeneously. Here, we found that bovine insulin protofibril formation proceeds in a monodisperse manner, which allowed us to characterize the detailed early aggregation process by light scattering in combination with thioflavin T fluorescence and Fourier transform infrared spectroscopy. The protofibril formation was specific to bovine insulin, whereas no significant aggregation was observed in human insulin. The kinetic analysis combining static and dynamic light scattering data revealed that the protofibril formation process in bovine insulin can be divided into two steps based on fractal dimension. When modeling the experimental data based on Smoluchowski aggregation kinetics, an aggregation scheme consisting of initial fractal aggregation forming spherical oligomers and their subsequent end-to-end association forming protofibrils was clarified. Furthermore, the analysis of temperature and salt concentration dependencies showed that the end-to-end association is the rate-limiting step, involving dehydration. The established model for protofibril formation, wherein oligomers are incorporated as a precursor, provides insight into the molecular mechanism by which protein molecules assemble during the early stage of amyloid formation.


Asunto(s)
Amiloide , Insulinas , Animales , Bovinos , Humanos , Amiloide/química , Insulinas/química , Cinética , Espectroscopía Infrarroja por Transformada de Fourier
5.
Methods Mol Biol ; 2755: 201-212, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38319580

RESUMEN

The hypoxic microenvironment in solid tumors affects the metabolism of tumor cells and infiltrating immune cells, which aids in robust tumor growth and expansion. Myeloid-derived suppressor cells (MDSCs) are heterogenous immature myeloid cells in the TME, which play an essential role in immune evasion by subverting T/NK cell-mediated killing. The immunosuppressive function of MDSCs is tightly regulated to the metabolic pathways, in which hypoxia plays a critical role. In this chapter, we describe the isolation of murine MDSCs from bone marrows and the measurement of the transcriptomic changes of essential metabolic enzymes under hypoxic conditions. This method can be applied to study MDSCs function, mimicking the hypoxic environment in vitro. This method can be utilized to investigate the critical metabolic alterations under a given tumor context and help evaluate the efficacy of metabolic-targeted therapies in the long run.


Asunto(s)
Perfilación de la Expresión Génica , Células Mieloides , Animales , Ratones , Hidrolasas , Hipoxia , Evasión Inmune
6.
Membranes (Basel) ; 14(2)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38392670

RESUMEN

Lysosomal degradation of tyrosinase, a pivotal enzyme in melanin synthesis, negatively impacts melanogenesis in melanocytes. Nevertheless, the precise molecular mechanisms by which lysosomes target tyrosinase have remained elusive. Here, we identify RING (Really Interesting New Gene) finger protein 152 (RNF152) as a membrane-associated ubiquitin ligase specifically targeting tyrosinase for the first time, utilizing AlphaScreen technology. We observed that modulating RNF152 levels in B16 cells, either via overexpression or siRNA knockdown, resulted in decreased or increased levels of both tyrosinase and melanin, respectively. Notably, RNF152 and tyrosinase co-localized at the trans-Golgi network (TGN). However, upon treatment with lysosomal inhibitors, both proteins appeared in the lysosomes, indicating that tyrosinase undergoes RNF152-mediated lysosomal degradation. Through ubiquitination assays, we found the indispensable roles of both the RING and transmembrane (TM) domains of RNF152 in facilitating tyrosinase ubiquitination. In summary, our findings underscore RNF152 as a tyrosinase-specific ubiquitin ligase essential for regulating melanogenesis in melanocytes.

7.
J Biochem ; 175(2): 133-140, 2024 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-37943501

RESUMEN

Blebs are membrane structures formed by the detachment of the plasma membrane from the underlying actin cytoskeleton. It is now clear that a wide variety of cells, including cancer cells, actively form blebs for cell migration and cell survival. The expansion of blebs has been regarded as the passive ballooning of the plasma membrane by an abrupt increase in intracellular pressure. However, recent studies revealed the importance of 'cytoplasmic zoning', i.e. local changes in the hydrodynamic properties and the ionic and protein content of the cytoplasm. In this review, we summarize the current understanding of the molecular mechanisms behind cytoplasmic zoning and its role in bleb expansion.


Asunto(s)
Citoesqueleto de Actina , Actinas , Citoplasma/metabolismo , Citosol/metabolismo , Membrana Celular/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo
8.
Cancer Discov ; 14(1): 176-193, 2024 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-37931287

RESUMEN

Nutritional factors play crucial roles in immune responses. The tumor-caused nutritional deficiencies are known to affect antitumor immunity. Here, we demonstrate that pancreatic ductal adenocarcinoma (PDAC) cells can suppress NK-cell cytotoxicity by restricting the accessibility of vitamin B6 (VB6). PDAC cells actively consume VB6 to support one-carbon metabolism, and thus tumor cell growth, causing VB6 deprivation in the tumor microenvironment. In comparison, NK cells require VB6 for intracellular glycogen breakdown, which serves as a critical energy source for NK-cell activation. VB6 supplementation in combination with one-carbon metabolism blockage effectively diminishes tumor burden in vivo. Our results expand the understanding of the critical role of micronutrients in regulating cancer progression and antitumor immunity, and open new avenues for developing novel therapeutic strategies against PDAC. SIGNIFICANCE: The nutrient competition among the different tumor microenvironment components drives tumor growth, immune tolerance, and therapeutic resistance. PDAC cells demand a high amount of VB6, thus competitively causing NK-cell dysfunction. Supplying VB6 with blocking VB6-dependent one-carbon metabolism amplifies the NK-cell antitumor immunity and inhibits tumor growth in PDAC models. This article is featured in Selected Articles from This Issue, p. 5.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Vitamina B 6 , Microambiente Tumoral , Células Asesinas Naturales , Neoplasias Pancreáticas/patología , Carcinoma Ductal Pancreático/patología , Carbono
9.
Mar Drugs ; 21(12)2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38132935

RESUMEN

R-type lectins are a widespread group of sugar-binding proteins found in nearly all domains of life, characterized by the presence of a carbohydrate-binding domain that adopts a ß-trefoil fold. Mytilectins represent a recently described subgroup of ß-trefoil lectins, which have been functionally characterized in a few mussel species (Mollusca, Bivalvia) and display attractive properties, which may fuel the development of artificial lectins with different biotechnological applications. The detection of different paralogous genes in mussels, together with the description of orthologous sequences in brachiopods, supports the formal description of mytilectins as a gene family. However, to date, an investigation of the taxonomic distribution of these lectins and their molecular diversification and evolution was still lacking. Here, we provide a comprehensive overview of the evolutionary history of mytilectins, revealing an ancient monophyletic evolutionary origin and a very broad but highly discontinuous taxonomic distribution, ranging from heteroscleromorphan sponges to ophiuroid and crinoid echinoderms. Moreover, the overwhelming majority of mytilectins display a chimera-like architecture, which combines the ß-trefoil carbohydrate recognition domain with a C-terminal pore-forming domain, suggesting that the simpler structure of most functionally characterized mytilectins derives from a secondary domain loss.


Asunto(s)
Bivalvos , Lectinas , Animales , Lectinas/química , Evolución Molecular , Bivalvos/metabolismo , Carbohidratos/genética
10.
Mol Ther Nucleic Acids ; 34: 102054, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38111913

RESUMEN

Gemcitabine is an effective chemotherapeutic agent for biliary tract cancers (BTCs), including gallbladder cancer (GBC) and cholangiocarcinoma (CCA). However, few other effective agents are currently available, particularly for GEM-refractory BTCs. We previously identified microRNA-451a (miR-451a) as a potential therapeutic target in GBC. To elucidate the antineoplastic effects of miR-451a and its underlying mechanisms, we transfected miR-451a into GBC, gemcitabine-resistant GBC (GR-GBC), and gemcitabine-resistant CCA (GR-CCA) cell lines. Furthermore, mimicking in vivo conditions, tumorigenic GBC organoids and three-dimensional (3D) cell culture systems were employed to investigate the anti-proliferative effects of miR-451a on BTCs, and its effect on stem cell properties. We found that miR-451a significantly inhibited cell proliferation, induced apoptosis, and reduced chemoresistant phenotypes, such as epithelial-mesenchymal transition, in both GBC and GR-GBC. The principal mechanism is probably the negative regulation of the phosphatidylinositol 3-kinase/AKT pathway, partially accomplished by directly downregulating macrophage migration inhibitory factor. The Gene Expression Omnibus database revealed that miR-451a was the most significantly downregulated microRNA in CCA tissues. The introduction of miR-451a resulted in similar antineoplastic effects in GR-CCA. Furthermore, miR-451a reduced cell viability in 3D spheroid models and tumorigenic GBC organoids. These findings suggest that the supplementation of miR-451a is a potential treatment strategy for GEM-refractory BTCs.

11.
Pancreatology ; 23(8): 988-995, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37951728

RESUMEN

BACKGROUND: EUS-FNA/B for pancreatic ductal adenocarcinoma (PDAC) is generally considered to be safe; however, while the incidence is low, there are occurrences of complications. Among these complications, there are serious ones like needle tract seeding (NTS), and it is not known than which types of tumors have the risks of EUS-FNA/B complications. This study aimed to evaluate the risk of EUS-FNA/B complications in patients with PDAC, focusing on morphological features. METHODS: Overall, 442 patients who underwent EUS-FNA/B for solid pancreatic masses between January 2018 and May 2022 in four institutions were retrospectively surveyed. Finally, 361 patients histopathologically diagnosed with PDAC were analyzed. Among these patients, 79 tumors with cysts or necrotic components were compared with 282 tumors without cysts or necrotic components. The incidence and risk of EUS-FNA/B complications including NTS were evaluated. RESULTS: There were 9 (2.4 %) of total EUS-FNA/B complications and 3 (0.8 %) of NTS. The incidence of total complication rate and NTS in tumors with cysts or necrotic components were significantly higher than in those without cysts or necrotic components (total complication 6.3 % vs. 1.4 %, p = 0.026, NTS 3.7 % vs. 0 %, p = 0.01). The transgastric route of puncture (OR: 93.3, 95 % CI: 3.81-2284.23) and the existence of cysts or necrotic components (OR: 7.3, 95 % CI: 1.47-36.19) were risk factors for EUS-FNA/B complications identified by the multivariate analysis. CONCLUSIONS: We should pay attention to the risks of EUS-FNA/B complications, including NTS, when the tumor has cysts or necrotic components.


Asunto(s)
Carcinoma Ductal Pancreático , Quistes , Neoplasias Pancreáticas , Humanos , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/efectos adversos , Estudios Retrospectivos , Neoplasias Pancreáticas/patología , Carcinoma Ductal Pancreático/patología
12.
Rinsho Shinkeigaku ; 63(12): 824-829, 2023 Dec 19.
Artículo en Japonés | MEDLINE | ID: mdl-37989288

RESUMEN

A 62-year-old man was admitted to our hospital for acute bilateral blindness two days after a head injury. Hemorrhagic cerebellar infarction was found on the initial MRI, and peripheral arteries were poorly visualized on MRA. On the follow-up MRA nine days later, peripheral arteries were clearly depicted. These imaging findings suggested reversible cerebral vasoconstriction syndrome (RCVS). We started steroid pulse therapy for suspected optic neuritis with no clear response. The initial fundoscopic examination revealed no abnormalities in the optic disc, but optic nerve atrophy developed one month later. Based on the course of events, we diagnosed the patient with posterior ischemic optic neuropathy triggered by RCVS.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Trastornos Cerebrovasculares , Masculino , Humanos , Persona de Mediana Edad , Vasoconstricción/fisiología , Imagen por Resonancia Magnética , Ceguera
13.
Therap Adv Gastroenterol ; 16: 17562848231206980, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37900006

RESUMEN

Background: Drainage exceeding 50% of total liver volume is a beneficial prognostic factor in patients with unresectable malignant hilar biliary obstruction (UMHBO). However, it is unclear what threshold percentage of total liver volume drained ('liver drainage rate') significantly improves survival in patients with UMHBO who received systemic chemotherapy. Objectives: We aimed to assess the optimal liver drainage rate that improves survival in patients with UMHBO receiving chemotherapy using a three-dimensional (3D)-image volume analyzer. Design: This study was a single-center retrospective cohort study. Methods: Data from 90 patients with UMHBO who received chemotherapy after endoscopic biliary drainage using metal stents at Okayama University Hospital from January 2003 to December 2020 were reviewed. The liver drainage rate was calculated by dividing the drained liver volume by the total liver volume using a 3D-image volume analyzer. The primary endpoint was overall survival by liver drainage rate. The secondary endpoints were time to recurrent biliary obstruction (TRBO) and prognostic factors. Results: The median total liver volume was 1172 (range: 673-2032) mL, and the median liver drainage rate was 83% (range: 50-100). Overall survival was 376 (95% CI: 271-450) days, and patients with >80% drainage (n = 67) had significantly longer survival than those with <80% drainage (n = 23) (450 days versus 224 days, p = 0.0033, log-rank test). TRBO was 201 (95% CI: 155-327) days and did not differ significantly by liver drainage rate. Multivariate Cox proportional hazards regression analysis revealed >80% liver drainage [hazard ratio (HR): 0.35, 95% CI: 0.20-0.62, p = 0.0003] and hilar cholangiocarcinoma (HR: 0.30, 95% CI: 0.17-0.50, p < 0.0001) as significant prognostic factors. Conclusion: In patients with UMHBO scheduled for chemotherapy, >80% drainage is associated with improved survival. Further prospective multicenter studies are needed to verify the results of this study. Trail registration: Okayama University Hospital, IRB number: 2108-011.

14.
Int J Biol Macromol ; 253(Pt 8): 127628, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37884254

RESUMEN

MytiLec-1, the recombinant form of a mussel lectin from Mytillus galloprovincialis, was purified by affinity chromatography and showed the maximum hemagglutination activity at a temperature range of 10 °C to 40 °C and at pH 7.0 to 9.0. Denaturants like urea and acidic-guanidine inhibited its hemagglutination activity significantly. MytiLec-1 was found to be metal-independent though Ca2+ slightly increased the activity of chelated MytiLec-1. The lectin suppressed 65 % growth of Pseudomonas aeruginosa (ATCC 47085) at 200 µg/ml and reduced the formation of biofilm (15 % at 200 µg/ml). Comparing to Shigella sonnei (ATCC 29930), Shigella boydii (ATCC 231903) and Shigella dysenteriae (ATCC 238135), Bacillus cereus (ATCC 14579) was slightly more sensitive to MytiLec-1. At a concentration of 200 µg/disc and 100 µg/ml, MytiLec-1 prevented the growth of Aspergillus niger and agglutinated the spores of Aspergillus niger and Trichoderma reesei, respectively. Amino acid sequences, physicochemical properties and antimicrobial activities of MytiLec-1 were compared with three other lectins (CGL, MTL and MCL from Crenomytilus grayanus, Mytilus trossulas and Mytilus californianus, respectively) from the mytilectin family of bivalve mollusks. It reconfirms the function of these lectins to recognize pathogens and perform important roles in innate immune response of mussels.


Asunto(s)
Antiinfecciosos , Mytilus , Animales , Lectinas/química , Mytilus/química , Disacáridos/metabolismo , Antiinfecciosos/farmacología , Antiinfecciosos/metabolismo
15.
Dig Endosc ; 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37885412

RESUMEN

OBJECTIVES: For preoperative biliary drainage (PBD) of malignant hilar biliary obstruction (MHBO), current guidelines recommend endoscopic nasobiliary drainage (ENBD) due to the higher risk of cholangitis after endoscopic biliary stenting (EBS) during the waiting period before surgery. However, few studies have supported this finding. Therefore, we aimed to compare the outcomes of preoperative ENBD and EBS in patients with MHBO. METHODS: Patients with MHBO who underwent laparotomy for radical surgery after ENBD or EBS were included from retrospectively collected data from 13 centers (January 2014 to December 2018). We performed a 1:1 propensity score matching between the ENBD and EBS groups. These patients were compared for the following: cholangitis and all adverse events (AEs) after endoscopic biliary drainage (EBD) until surgery, time to cholangitis development after EBD, postsurgical AEs, and in-hospital death after surgery. RESULTS: Of the 414 patients identified, 355 were analyzed in this study (226 for ENBD and 129 for EBS). The matched cohort included 63 patients from each group. The proportion of cholangitis after EBD was similar between the two groups (20.6% vs. 25.4%, P = 0.67), and no significant difference was observed in the time to cholangitis development. The proportions of surgical site infections, bile leaks, and in-hospital mortality rates were similar between the groups. CONCLUSION: For PBD of MHBO, the proportion of AEs, including cholangitis, after EBD until surgery was similar when either ENBD or EBS was used.

16.
Acta Med Okayama ; 77(5): 517-525, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37899263

RESUMEN

We investigated the effect of modified FOLFIRINOX (mFFX) in unresectable pancreatic cancer by retrospectively analyzing the cases of 43 patients who underwent BRCA testing (germline, n=11; somatic, n=26; both germline and somatic, n=6). The association between BRCA mutations and therapeutic effect was clarified. Six patients tested positive for germline pathogenic variants. Familial pancreatic cancer (33% vs. 3%, p=0.006) and peritoneal disseminated lesions (66% vs. 8%, p<0.001) were significantly more common in patients with germline pathogenic variants. The partial response (PR) rate was 100% in the germline BRCA-positive patients, and 27% in the germline BRCA-negative patients (p<0.001). The median progression-free survival (PFS) was not reached for any germline BRCA-positive patients but was 9.0 months for the germline BRCA-negative patients (p=0.042). Patients with stage IV BRCA-associated pancreatic cancer had better overall survival than those with non-BRCA-associated pancreatic cancer, although the difference was nonsignificant (not reached vs. 655 days, p=0.061). Our results demonstrate that a PR and prolonged PFS can be expected in germline BRCA-positive patients after treatment with mFFX. Our findings also suggest that germline BRCA pathogenic variants may be useful as biomarkers for the therapeutic effect of mFFX in patients with pancreatic cancer.


Asunto(s)
Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estudios Retrospectivos , Neoplasias Pancreáticas
17.
ACS Appl Bio Mater ; 6(10): 4304-4313, 2023 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-37750824

RESUMEN

A formate (HCOO-) bioanode was developed by utilizing a phenothiazine-based electropolymerized layer deposited on sucrose-derived carbon. The electrode modified with NAD-dependent formate dehydrogenase and the electropolymerized layer synergistically catalyzed the oxidation of the coenzyme (NADH) and fuel (HCOO-) to achieve efficient electron transfer. Further, the replacement of carbon nanotubes with water-dispersible sucrose-derived carbon used as the electrode base allowed the fabrication of a surfactant-free bioanode delivering a maximum current density of 1.96 mA cm-2 in the fuel solution. Finally, a separator- and surfactant-free HCOO-/O2 biofuel cell featuring the above bioanode and a gas-diffusion biocathode modified with bilirubin oxidase and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) was fabricated, delivering a maximum power density of 70 µW cm-2 (at 0.24 V) and an open-circuit voltage of 0.59 V. Thus, this study demonstrates the potential of formic acid as a fuel and possibilities for the application of carbon materials in bioanodes.


Asunto(s)
Fuentes de Energía Bioeléctrica , Nanotubos de Carbono , Tensoactivos , Formiatos , Fenotiazinas , Sacarosa
18.
Anal Bioanal Chem ; 415(27): 6689-6700, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37714971

RESUMEN

Guanosine triphosphate (GTP) and adenosine triphosphate (ATP) are essential nucleic acid building blocks and serve as energy molecules for a wide range of cellular reactions. Cellular GTP concentration fluctuates independently of ATP and is significantly elevated in numerous cancers, contributing to malignancy. Quantitative measurement of ATP and GTP has become increasingly important to elucidate how concentration changes regulate cell function. Liquid chromatography-coupled mass spectrometry (LC-MS) and capillary electrophoresis-coupled MS (CE-MS) are powerful methods widely used for the identification and quantification of biological metabolites. However, these methods have limitations related to specialized instrumentation and expertise, low throughput, and high costs. Here, we introduce a novel quantitative method for GTP concentration monitoring (GTP-quenching resonance energy transfer (QRET)) in homogenous cellular extracts. CE-MS analysis along with pharmacological control of cellular GTP levels shows that GTP-QRET possesses high dynamic range and accuracy. Furthermore, we combined GTP-QRET with luciferase-based ATP detection, leading to a new technology, termed QT-LucGTP&ATP, enabling high-throughput compatible dual monitoring of cellular GTP and ATP in a homogenous fashion. Collectively, GTP-QRET and QT-LucGTP&ATP offer a unique, high-throughput opportunity to explore cellular energy metabolism, serving as a powerful platform for the development of novel therapeutics and extending its usability across a range of disciplines.


Asunto(s)
Adenosina Trifosfato , Adenosina , Guanosina Trifosfato/química , Guanosina Trifosfato/metabolismo , Adenosina Trifosfato/metabolismo , Guanosina , Cromatografía Liquida
19.
BMC Gastroenterol ; 23(1): 296, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37667224

RESUMEN

BACKGROUND: The sedation method used during double-balloon endoscopic retrograde cholangiopancreatography (DB-ERCP) differs among countries and/or facilities, and there is no established method. This study aimed to evaluate the efficacy of non-anesthesiologist-administered propofol (NAAP) sedation using a target-controlled infusion (TCI) system during DB-ERCP. METHODS: This retrospective study was conducted between May 2017 and December 2020 at an academic center. One hundred and fifty-six consecutive patients who underwent DB-ERCP were sedated by gastroenterologists using diazepam (n = 77) or propofol with a TCI system (n = 79), depending on the period. The primary endpoint was a comparison of poor sedation rates between the two groups. Poor sedation was defined as a condition requiring the use of other sedative agents or discontinuation of the procedure. Secondary endpoints were sedation-related adverse events and risk factors for poor sedation. RESULTS: Poor sedation occurred significantly more often in the diazepam sedation group (diazepam sedation, n = 12 [16%] vs. propofol sedation, n = 1 [1%]; P = 0.001). Vigorous body movements (3 or 4) (diazepam sedation, n = 40 [52%] vs. propofol sedation, n = 28 [35%]; P = 0.038) and hypoxemia (< 85%) (diazepam sedation, n = 7 [9%] vs. propofol sedation, n = 1 [1%]; P = 0.027) occurred significantly more often in the diazepam sedation group. In the multivariate analysis, age < 70 years old (OR, 10.26; 95% CI, 1.57-66.98; P = 0.015), BMI ≥ 25 kg/m2 (OR, 11.96; 95% CI, 1.67-85.69; P = 0.014), and propofol sedation (OR, 0.06; 95% CI, 0.01-0.58; P = 0.015) were associated factors for poor sedation. CONCLUSIONS: NAAP sedation with the TCI system during DB-ERCP was safer and more effective than diazepam sedation.


Asunto(s)
Propofol , Humanos , Anciano , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Estudios Retrospectivos , Hipnóticos y Sedantes , Diazepam
20.
Vet Microbiol ; 284: 109829, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37451183

RESUMEN

Enzootic bovine leukosis (EBL) is typically observed in cattle older than 3 years, but some cases of onset in cattle younger than 3 years have been reported in Japan. BoLA-DRB3 polymorphisms are associated with susceptibility to EBL onset. However, little is known about the relationship between the polymorphisms and EBL onset in young cattle. In the present study, we performed BoLA-DRB3 genotyping in 59 EBL cattle younger than 3 years (25 Holstein-Friesian and 34 Japanese Black) and compared the results with those of 69 EBL cattle older than 3 years (38 Holstein-Friesian and 31 Japanese Black). The BoLA-DRB3*15:01 allele was detected at a frequency of 37.3 % (48.0 % and 29.4 % in Holstein-Friesian and Japanese Black, respectively) and was identified as an early EBL onset susceptibility allele. Nine EBL cattle younger than 3 years (5 Holstein-Friesian and 4 Japanese Black), but only 1 EBL cattle older than 3 years (1 Holstein-Friesian), had a BoLA-DRB3*15:01/*15:01 homozygous genotype. The frequency of the BoLA-DRB3*15:01 allele occurring with a different allele (BoLA-DRB3*015:01/other) in cattle younger than 3 years was 44.1 % (56.0 % Holstein-Friesian and 35.3 % Japanese Black) and significantly higher than that in cattle older than 3 years (28.9 % Holstein-Friesian and 9.7 % Japanese Black) (P = 0.0013). These results suggest that BoLA-DRB3*15:01/*15:01 and BoLA-DRB3*15:01/other genotypes are early EBL onset susceptibility genotypes. The present findings may contribute to cattle breeding selection.


Asunto(s)
Enfermedades de los Bovinos , Leucosis Bovina Enzoótica , Bovinos/genética , Animales , Leucosis Bovina Enzoótica/genética , Alelos , Antígenos de Histocompatibilidad Clase II/genética , Polimorfismo Genético
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