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1.
Am J Gastroenterol ; 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38084857

RESUMEN

INTRODUCTION: Despite the serious risks of diabetes with hepatitis C virus (HCV) infection, this preventable comorbidity is rarely a priority for HCV elimination. We aim to examine how a shared care model could eliminate HCV in patients with diabetes (PwD) in primary care. METHODS: There were 27 community-based Diabetes Health Promotion Institutes in each township/city of Changhua, Taiwan. PwD from these institutes from January 2018 to December 2020 were enrolled. HCV screening and treatment were integrated into diabetes structured care through collaboration between diabetes care and HCV care teams. Outcome measures included HCV care continuum indicators. Township/city variation in HCV infection prevalence and care cascades were also examined. RESULTS: Of the 10,684 eligible PwD, 9,984 (93.4%) underwent HCV screening, revealing a 6.18% (n = 617) anti-HCV seroprevalence. Among the 597 eligible seropositive individuals, 507 (84.9%) completed the RNA test, obtaining 71.8% positives. Treatment was initiated by 327 (89.8%) of 364 viremic patients, and 315 (86.5%) completed it, resulting in a final cure rate of 79.4% (n = 289). Overall, with the introduction of antivirals in this cohort, the prevalence of viremic HCV infection dropped from 4.44% to 1.34%, yielding a 69.70% (95% credible interval 63.64%-77.03%) absolute reduction. DISCUSSION: Although HCV prevalence varied, the care cascades achieved consistent results across townships/cities. We have further successfully implemented the model in county-wide hospital-based diabetes clinics, eventually treating 89.6% of the total PwD. A collaborative effort between diabetes care and HCV elimination enhanced the testing and treatment in PwD through an innovative shared care model.

2.
Sensors (Basel) ; 24(3)2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38339451

RESUMEN

Gait analysis has been studied over the last few decades as the best way to objectively assess the technical outcome of a procedure designed to improve gait. The treating physician can understand the type of gait problem, gain insight into the etiology, and find the best treatment with gait analysis. The gait parameters are the kinematics, including the temporal and spatial parameters, and lack the activity information of skeletal muscles. Thus, the gait analysis measures not only the three-dimensional temporal and spatial graphs of kinematics but also the surface electromyograms (sEMGs) of the lower limbs. Now, the shoe-worn GaitUp Physilog® wearable inertial sensors can easily measure the gait parameters when subjects are walking on the general ground. However, it cannot measure muscle activity. The aim of this study is to measure the gait parameters using the sEMGs of the lower limbs. A self-made wireless device was used to measure the sEMGs from the vastus lateralis and gastrocnemius muscles of the left and right feet. Twenty young female subjects with a skeletal muscle index (SMI) below 5.7 kg/m2 were recruited for this study and examined by the InBody 270 instrument. Four parameters of sEMG were used to estimate 23 gait parameters. They were measured using the GaitUp Physilog® wearable inertial sensors with three machine learning models, including random forest (RF), decision tree (DT), and XGBoost. The results show that 14 gait parameters could be well-estimated, and their correlation coefficients are above 0.800. This study signifies a step towards a more comprehensive analysis of gait with only sEMGs.


Asunto(s)
Marcha , Caminata , Adulto , Humanos , Electromiografía , Marcha/fisiología , Caminata/fisiología , Análisis de la Marcha , Aprendizaje Automático , Fenómenos Biomecánicos
3.
Molecules ; 26(9)2021 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-33922675

RESUMEN

Although the anti-allergic and prebiotic activities of diosgenin have been reported, the influence of diosgenin on intestinal immune and epithelial cells remains unclear. As the gut microbiota plays an important role in allergic disorders, this study aimed to investigate whether the anti-allergic diarrhea effect of diosgenin occurs via improving gut dysbiosis. In a murine food allergy model, the density of fecal bacterial growth on de Man, Rogossa and Sharpe (MRS) plates was diminished, and growth on reinforced clostridial medium (RCM) and lysogeny broth (LB) agar plates was elevated. However, the oral administration of diosgenin reduced the density of fecal bacteria and ameliorated diarrhea severity. Concordantly, reshaped diversity and an abundance of fecal microbes were observed in some of the diosgenin-treated mice, which showed a milder severity of diarrhea. The relevant fecal strains from the diosgenin-treated mice were defined and cultured with Caco-2 cells and allergen-primed mesenteric lymph node (MLN) cells. These strains exhibited protective effects against the cytokine/chemokine network and allergen-induced T-cell responses to varying degrees. By contrast, diosgenin limitedly regulated cytokine production and even reduced cell viability. Taken together, these findings show that diosgenin per se could not directly modulate the functionality of intestinal epithelial cells and immune cells, and its anti-allergic effect is most likely exerted via improving gut dysbiosis.


Asunto(s)
Antialérgicos/uso terapéutico , Diosgenina/uso terapéutico , Disbiosis/tratamiento farmacológico , Hipersensibilidad a los Alimentos/tratamiento farmacológico , Animales , Células CACO-2 , Modelos Animales de Enfermedad , Microbioma Gastrointestinal , Humanos , Ratones
4.
Mol Cell ; 45(2): 171-84, 2012 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-22196886

RESUMEN

Proinflammatory cytokine TNFα plays critical roles in promoting malignant cell proliferation, angiogenesis, and tumor metastasis in many cancers. However, the mechanism of TNFα-mediated tumor development remains unclear. Here, we show that IKKα, an important downstream kinase of TNFα, interacts with and phosphorylates FOXA2 at S107/S111, thereby suppressing FOXA2 transactivation activity and leading to decreased NUMB expression, and further activates the downstream NOTCH pathway and promotes cell proliferation and tumorigenesis. Moreover, we found that levels of IKKα, pFOXA2 (S107/111), and activated NOTCH1 were significantly higher in hepatocellular carcinoma tumors than in normal liver tissues and that pFOXA2 (S107/111) expression was positively correlated with IKKα and activated NOTCH1 expression in tumor tissues. Therefore, dysregulation of NUMB-mediated suppression of NOTCH1 by TNFα/IKKα-associated FOXA2 inhibition likely contributes to inflammation-mediated cancer pathogenesis. Here, we report a TNFα/IKKα/FOXA2/NUMB/NOTCH1 pathway that is critical for inflammation-mediated tumorigenesis and may provide a target for clinical intervention in human cancer.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Transformación Celular Neoplásica/metabolismo , Factor Nuclear 3-beta del Hepatocito/genética , Quinasa I-kappa B/metabolismo , Neoplasias Hepáticas/metabolismo , Receptor Notch1/metabolismo , Animales , Carcinoma Hepatocelular/patología , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Factor Nuclear 3-beta del Hepatocito/metabolismo , Humanos , Neoplasias Hepáticas Experimentales/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Modelos Biológicos , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Fosforilación , Receptor Notch1/genética , Transducción de Señal , Factor de Necrosis Tumoral alfa/metabolismo
5.
Dev Dyn ; 244(12): 1485-518, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26316229

RESUMEN

BACKGROUND: Artificial selection of postembryonic features is known to have established morphological variation in goldfish (Carassius auratus). Although previous studies have suggested that goldfish and zebrafish are almost directly comparable at the embryonic level, little is known at the postembryonic level. RESULTS: Here, we categorized the postembryonic developmental process in the wild-type goldfish into 11 different stages. We also report certain differences between the postembryonic developmental processes of goldfish and zebrafish, especially in the skeletal systems (scales and median fin skeletons), suggesting that postembryonic development underwent evolutionary divergence in these two teleost species. CONCLUSIONS: Our postembryonic staging system of wild-type goldfish paves the way for careful and appropriate comparison with other teleost species. The staging system will also facilitate comparative ontogenic analyses between wild-type and mutant goldfish strains, allowing us to closely study the relationship between artificial selection and molecular developmental mechanisms in vertebrates.


Asunto(s)
Aletas de Animales/crecimiento & desarrollo , Carpa Dorada/crecimiento & desarrollo , Piel/crecimiento & desarrollo , Animales , Evolución Biológica , Filogenia , Pez Cebra/crecimiento & desarrollo
6.
Biochim Biophys Acta ; 1830(10): 4743-51, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23791554

RESUMEN

BACKGROUND: Hypoxia-inducible factor-1α (HIF-1α) is an important transcription factor that modulates cellular responses to hypoxia and also plays critical roles in cancer progression. Recently, somatic mutations and decreased copy number of mitochondrial DNA (mtDNA) were detected in hepatocellular carcinoma (HCC). These mutations were shown to have the potential to cause mitochondrial dysfunction. However, the effects and mechanisms of mitochondrial dysfunction on HIF-1α function are not fully understood. This study aims to explore the underlying mechanism by which mitochondrial dysfunction regulates HIF-1α expression. METHODS: Human hepatoma HepG2 cells were treated with various mitochondrial respiration inhibitors and an uncoupler, respectively, and the mRNA and protein expressions as well as transactivation activity of HIF-1α were determined. The role of AMP-activated protein kinase (AMPK) was further analyzed by compound C and AMPK knock-down. RESULTS: Treatments of mitochondrial inhibitors and an uncoupler respectively reduced both the protein level and transactivation activity of HIF-1α in HepG2 cells under normoxia or hypoxia. The mitochondrial dysfunction-repressed HIF-1α protein synthesis was associated with decreased phosphorylations of p70(S6K) and 4E-BP-1. Moreover, mitochondrial dysfunction decreased intracellular ATP content and elevated the phosphorylation of AMPK. Treatments with compound C, an AMPK inhibitor, and knock-down of AMPK partially rescued the mitochondrial dysfunction-repressed HIF-1α expression. CONCLUSIONS: Mitochondrial dysfunctions resulted in reduced HIF-1α protein synthesis through AMPK-dependent manner in HepG2 cells. GENERAL SIGNIFICANCE: Our results provided a mechanism for communication from mitochondria to the nucleus through AMPK-HIF-1α. Mitochondrial function is important for HIF-1α expression in cancer progression.


Asunto(s)
Adenilato Quinasa/metabolismo , Carcinoma Hepatocelular/enzimología , Subunidad alfa del Factor 1 Inducible por Hipoxia/biosíntesis , Neoplasias Hepáticas/enzimología , Mitocondrias/fisiología , Secuencia de Bases , Carcinoma Hepatocelular/patología , Cartilla de ADN , Activación Enzimática , Células Hep G2 , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Neoplasias Hepáticas/patología , Reacción en Cadena en Tiempo Real de la Polimerasa
7.
J Pharmacol Sci ; 125(4): 375-85, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25141924

RESUMEN

This study investigated the herb-drug interaction of xanthorrhizol and tamoxifen in human breast cancer cells. Using MCF-7 cell line as an in vitro model, the herb-drug interaction between xanthorrhizol and tamoxifen was measured by MTT assay, luciferase reporter assay, and cell cycle analysis. The effects of xanthorrhizol on growth/autophagy related signaling were determined by immunostaining, western blotting, and real time RT-PCR. Additionally, the in vivo effect of xanthorrhizol and tamoxifen on athymic nude mice implanted with MCF-7 cells was evaluated. When MCF-7 cells were co-treated with tamoxifen and xanthorrhizol, there were no significant changes in terms of cell number, luciferase activity, percentage S-phase cells and LC3-II expression. However, using the MCF-7 implanted nude mice model, it was possible to detect significantly increased tumor volumes, a larger tumor size, and increased protein expression of P38 and P27(Kip1) in the xanthorrhizol + tamoxifen group compared to the tamoxifen-alone group. It can be concluded that while there is no significant herb-drug interaction between xanthorrhizol and tamoxifen in vitro, there is such an interaction in tumor-bearing mice, which provides important information that affects breast cancer treatment translational research.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Transformación Celular Neoplásica/efectos de los fármacos , Fenoles/administración & dosificación , Fenoles/efectos adversos , Tamoxifeno/administración & dosificación , Tamoxifeno/efectos adversos , Animales , Neoplasias de la Mama/genética , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Modelos Animales de Enfermedad , Quimioterapia Combinada , Femenino , Interacciones de Hierba-Droga , Humanos , Luciferasas/metabolismo , Células MCF-7 , Ratones Endogámicos BALB C , Ratones Desnudos , Proteínas Asociadas a Microtúbulos/metabolismo , Trasplante de Neoplasias , Fenoles/farmacología , Tamoxifeno/farmacología
8.
Cancer Cell ; 9(5): 367-78, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16697957

RESUMEN

We demonstrate that PTEN loss causes reduced NKX3.1 expression in both murine and human prostate cancers. Restoration of Nkx3.1 expression in vivo in Pten null epithelium leads to decreased cell proliferation, increased cell death, and prevention of tumor initiation. Whereas androgen receptor (AR) positively regulates NKX3.1 expression, NKX3.1 negatively modulates AR transcription and consequently the AR-associated signaling events. Consistent with its tumor suppressor functions, NKX3.1 engages cell cycle and cell death machinery via association with HDAC1, leading to increased p53 acetylation and half-life through MDM2-dependent mechanisms. Importantly, overexpression of Nkx3.1 has little effect on Pten wild-type epithelium, suggesting that PTEN plays a predominant role in PTEN-NKX3.1 interplay. Manipulating NKX3.1 expression may serve as a therapeutic strategy for treating PTEN-deficient prostate cancers.


Asunto(s)
Proteínas de Homeodominio/metabolismo , Fosfohidrolasa PTEN/deficiencia , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Factores de Transcripción/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Acetilación , Animales , Proliferación Celular , Regulación hacia Abajo/genética , Activación Enzimática , Epitelio/metabolismo , Epitelio/patología , Expresión Génica , Histona Desacetilasa 1 , Histona Desacetilasas/metabolismo , Humanos , Masculino , Ratones , Fosfohidrolasa PTEN/genética , Regiones Promotoras Genéticas/genética , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Unión Proteica , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-mdm2 , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Trasplantes
9.
Nature ; 453(7194): 529-33, 2008 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-18463637

RESUMEN

Cancer stem cells, which share many common properties and regulatory machineries with normal stem cells, have recently been proposed to be responsible for tumorigenesis and to contribute to cancer resistance. The main challenges in cancer biology are to identify cancer stem cells and to define the molecular events required for transforming normal cells to cancer stem cells. Here we show that Pten deletion in mouse haematopoietic stem cells leads to a myeloproliferative disorder, followed by acute T-lymphoblastic leukaemia (T-ALL). Self-renewable leukaemia stem cells (LSCs) are enriched in the c-Kit(mid)CD3(+)Lin(-) compartment, where unphosphorylated beta-catenin is significantly increased. Conditional ablation of one allele of the beta-catenin gene substantially decreases the incidence and delays the occurrence of T-ALL caused by Pten loss, indicating that activation of the beta-catenin pathway may contribute to the formation or expansion of the LSC population. Moreover, a recurring chromosomal translocation, T(14;15), results in aberrant overexpression of the c-myc oncogene in c-Kit(mid)CD3(+)Lin(-) LSCs and CD3(+) leukaemic blasts, recapitulating a subset of human T-ALL. No alterations in Notch1 signalling are detected in this model, suggesting that Pten inactivation and c-myc overexpression may substitute functionally for Notch1 abnormalities, leading to T-ALL development. Our study indicates that multiple genetic or molecular alterations contribute cooperatively to LSC transformation.


Asunto(s)
Leucemia-Linfoma de Células T del Adulto/patología , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Fosfohidrolasa PTEN/deficiencia , Fosfohidrolasa PTEN/genética , Animales , Complejo CD3/metabolismo , Proliferación Celular , Cromosomas de los Mamíferos/genética , Femenino , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/patología , Hibridación Fluorescente in Situ , Masculino , Ratones , Proteínas Proto-Oncogénicas c-kit/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Receptores de Antígenos de Linfocitos T/genética , Translocación Genética , beta Catenina/metabolismo
10.
Telemed J E Health ; 20(2): 175-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24320193

RESUMEN

OBJECTIVE: To investigate the effectiveness of shared care combined with telecare in type 2 diabetic patients in an underserved community in Asia. RESEARCH DESIGN AND METHODS: In total, 95 patients with type 2 diabetes who had a glycosylated hemoglobin (HbA1c) level of >7% were recruited from six community health centers in remote areas in Changhua County, Taiwan. All patients were randomly divided into intervention (shared care combined with telecare) and usual-care groups and followed up for 6 months. RESULTS: The decrease in HbA1c level was significantly greater in the intervention group than in the usual-care group (0.7 ± 1.3% versus 0.1 ± 1.0%, p=0.03). There were no significant differences in lipid profiles and blood pressure changes between the two groups. CONCLUSIONS: Shared care combined with telecare could significantly reduce HbA1c levels in type 2 diabetic patients with poor glycemic control in underserved rural communities. Further studies should be conducted to clarify the target users and to develop cost-effective interventions.


Asunto(s)
Diabetes Mellitus Tipo 2/terapia , Grupo de Atención al Paciente , Telemedicina/métodos , Glucemia/análisis , Diabetes Mellitus Tipo 2/sangre , Femenino , Hemoglobina Glucada/análisis , Accesibilidad a los Servicios de Salud , Humanos , Masculino , Área sin Atención Médica , Persona de Mediana Edad , Población Rural , Taiwán
11.
Cell Metab ; 36(1): 193-208.e8, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38171333

RESUMEN

Metabolic reprogramming is key for cancer development, yet the mechanism that sustains triple-negative breast cancer (TNBC) cell growth despite deficient pyruvate kinase M2 (PKM2) and tumor glycolysis remains to be determined. Here, we find that deficiency in tumor glycolysis activates a metabolic switch from glycolysis to fatty acid ß-oxidation (FAO) to fuel TNBC growth. We show that, in TNBC cells, PKM2 directly interacts with histone methyltransferase EZH2 to coordinately mediate epigenetic silencing of a carnitine transporter, SLC16A9. Inhibition of PKM2 leads to impaired EZH2 recruitment to SLC16A9, and in turn de-represses SLC16A9 expression to increase intracellular carnitine influx, programming TNBC cells to an FAO-dependent and luminal-like cell state. Together, these findings reveal a new metabolic switch that drives TNBC from a metabolically heterogeneous-lineage plastic cell state to an FAO-dependent-lineage committed cell state, where dual targeting of EZH2 and FAO induces potent synthetic lethality in TNBC.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Humanos , Neoplasias de la Mama Triple Negativas/metabolismo , Línea Celular Tumoral , Mutaciones Letales Sintéticas , Glucólisis , Carnitina
12.
J Plast Reconstr Aesthet Surg ; 75(1): 10-24, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34607781

RESUMEN

BACKGROUND: Urologic problems, such as urethral fistulas and strictures, are among the most frequent complications occurring after phalloplasty. Although many studies have reported successful phalloplasty and urethral reconstruction with reliable outcomes in transgender men, no method has become standardized so far. This study aimed to summarize the results of reports on urological complications and outcomes in transgender men with respect to various types of urethral reconstruction. METHODS: A comprehensive literature search of PubMed, Scopus, and Google Scholar databases was conducted for studies related to phalloplasty in transsexuals. Data on various phallic urethral techniques, urethral complications, and outcomes were collected and analyzed using the random-effects model. RESULTS: A total of 21 studies (1,566 patients) were included: eight studies (1,061 patients) on "tube-in-tube," nine studies (273 patients) on "prelaminated flap," and six studies (221 patients) on "second flap." Compared with the tube-in-tube technique, the prelaminated flap was associated with a significantly higher urethral stricture/stenosis rate; however, there was no difference between the prelaminated flap and the second flap techniques. For all phalloplasty patients, the pool rate of urethral fistula or stenosis is 48.9%, the rate of the ability to void while standing is 91.5%, occurrence rate of tactile or erogenous sensation is 88%, the prosthesis complication rate is 27.9%, and patient-reported satisfactory outcome rate is 90.5%. CONCLUSION: Urethral reconstruction with a prelaminated flap was associated with a significantly higher urethral stricture rate and increased need of revision surgery compared with that observed using a skin flap. Overall, most patients were able to void while standing and were satisfied with the outcomes.


Asunto(s)
Cirugía de Reasignación de Sexo , Personas Transgénero , Transexualidad , Estrechez Uretral , Constricción Patológica/etiología , Humanos , Masculino , Pene/cirugía , Cirugía de Reasignación de Sexo/efectos adversos , Cirugía de Reasignación de Sexo/métodos , Transexualidad/cirugía , Uretra/cirugía , Estrechez Uretral/etiología , Estrechez Uretral/cirugía
13.
Antibiotics (Basel) ; 11(4)2022 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-35453250

RESUMEN

The World Health Organization indicated that antibiotic resistance is one of the greatest threats to health, food security, and development in the world. Drug resistance efflux pumps are essential for antibiotic resistance in bacteria. Here, we evaluated the plant phenolic compound ethyl 3,4-dihydroxybenzoate (EDHB) for its efflux pump inhibitory (EPI) activity against drug-resistant Escherichia coli. The half-maximal inhibitory concentration, modulation assays, and time-kill studies indicated that EDHB has limited antibacterial activity but can potentiate the activity of antibiotics for drug-resistant E. coli. Dye accumulation/efflux and MALDI-TOF studies showed that EDHB not only significantly increases dye accumulation and reduces dye efflux but also increases the extracellular amount of antibiotics in the drug-resistant E. coli, indicating its interference with substrate translocation via a bacterial efflux pump. Molecular docking analysis using AutoDock Vina indicated that EDHB putatively posed within the distal binding pocket of AcrB and in close interaction with the residues by H-bonds and hydrophobic contacts. Additionally, EDHB showed an elevated postantibiotic effect on drug-resistant E. coli. Our toxicity assays showed that EDHB did not change the bacterial membrane permeability and exhibited mild human cell toxicity. In summary, these findings indicate that EDHB could serve as a potential EPI for drug-resistant E. coli.

14.
ACS Omega ; 7(50): 46486-46493, 2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36570316

RESUMEN

ß-lactam-resistant Vibrio strains are a significant clinical problem, and ß-lactamase inhibitors are generally coadministered with ß-lactam drugs to control drug-resistant bacteria. Seaweed is a rich source of natural bioactive compounds; however, their potential as ß-lactamase inhibitors against bacterial pathogens remains unknown. Herein, we evaluated the potential ß-lactamase inhibitory effect of the ethanolic extracts of the red seaweed Gracilaria sp. (GE) against four Vibrio strains. The minimum inhibitory concentration, half-maximal inhibitory concentration, checkerboard assay results, and time-kill study results indicate that GE has limited antibacterial activity but can potentiate the activity of the ß-lactam antibiotic carbenicillin against Vibrio parahemolyticus and V. cholerae. We overexpressed and purified recombinant metallo-ß-lactamase, VarG, from V. cholerae for in vitro studies and observed that adding GE reduced the carbenicillin and nitrocefin degradation by VarG by 20% and 60%, respectively. Angiotensin I-converting enzyme inhibition studies demonstrated that GE did not inhibit VarG via metal chelation. Toxicity assays indicated that GE exhibited mild toxicity against human cells. Through gas chromatography and mass spectrometry, we showed that GE comprises alkaloids, phenolic compounds, terpenoids, terpenes, and halogenated aromatic compounds. This study revealed that extracts of the red seaweed Gracillaria sp. can potentially inhibit ß-lactamase activity.

15.
Biochim Biophys Acta ; 1800(3): 264-70, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19527772

RESUMEN

BACKGROUND: Somatic mutation in mitochondrial DNA (mtDNA) has been proposed to contribute to initiation and progression of human cancer. In our previous study, high frequency of somatic mutations was found in the D-loop region of mtDNA of gastric cancers. However, it is unclear whether somatic mutations occur in the coding region of mtDNA of gastric cancers. METHODS: Using DNA sequencing, we studied 31 gastric cancer specimens and corresponding non-cancerous stomach tissues. Moreover, a human gastric cancer SC-M1 cell line was treated with oligomycin to induce mitochondrial dysfunction. Cisplatin sensitivity and cell migration were analyzed. RESULTS: We identified eight somatic mutations in the coding region of mtDNAs of seven gastric cancer samples (7/31, 22.6%). Patients with somatic mutations in the entire mtDNA of gastric cancers did not show significant association with their clinicopathologic features. Among the eight somatic mutations, five point mutations (G3697A, G4996A, G9986A, C12405T and T13015C) are homoplasmic and three mutations (5895delC, 7472insC and 12418insA) are heteroplasmic. Four (4/8, 50%) of these somatic mutations result in amino acid substitutions in the highly conserved regions of mtDNA, which potentially lead to mitochondrial dysfunction. In addition, in vitro experiments in SC-M1 cells revealed that oligomycin-induced mitochondrial dysfunction promoted resistance to cisplatin and enhanced cell migration. N-acetyl cysteine was effective in the prevention of the oligomycin-enhanced migration, which suggests that reactive oxygen species generated by defective mitochondria may be involved in the enhanced migration of SC-M1 cells. GENERAL SIGNIFICANCE: Our results suggest that somatic mtDNA mutations and mitochondrial dysfunction may play an important role in the malignant progression of gastric cancer.


Asunto(s)
ADN Mitocondrial/genética , Genoma Mitocondrial/genética , Mutación , Neoplasias Gástricas/genética , Adenosina Trifosfato/metabolismo , Anciano , Sustitución de Aminoácidos , Técnicas de Cultivo de Célula/métodos , Movimiento Celular , Cartilla de ADN , ADN de Neoplasias/genética , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mitocondrias/patología , Mitocondrias/fisiología , Consumo de Oxígeno , Mutación Puntual , Polimorfismo de Nucleótido Simple , Eliminación de Secuencia , Estómago/fisiopatología , Neoplasias Gástricas/patología
16.
FASEB Bioadv ; 3(6): 459-469, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34124601

RESUMEN

Vismodegib, a Smoothened antagonist, is clinically approved for treatment of human basal cell carcinoma (BCC), in the clinical trials of medulloblastoma (MB) and other cancers. However, a significant proportion of these tumors fail to respond to Vismodegib after a period of treatment. Here, we find that AMPK agonists, A769662, and Metformin, can inhibit GLI1 activity and synergize with Vismodegib to suppress MB cell growth in vitro and in vivo. Furthermore, combination of AMPK agonists with Vismodegib is effective in overcoming Vismodegib-resistant MB. This is the first report demonstrating that combining AMPK agonist (Metformin) and SHH pathway inhibitor (Vismodegib) confers synergy for MB treatment and provides an effective chemotherapeutic regimen that can be used to overcome resistance to Vismodegib in SHH-driven cancers.

17.
Front Oncol ; 11: 646167, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33859945

RESUMEN

A low NM23-H1 expression in head and neck squamous cell carcinoma (HNSCC) was found to be associated with poor clinical outcome. Therefore, we investigated the role of NM23-H1 in the susceptibility of HNSCC cells to irradiation and its clinical significance. An in vitro study was also conducted to validate the results. Furthermore, we used immunohistochemistry to analyze NM23-H1 expression found in specimens of 50 HNSCC patients with cervical metastases receiving postoperative radiotherapy. Low tumor NM23-H1 expression was associated with locoregional recurrence of HNSCC (p=0.040; Hazard ratio=5.62) and poor clinical outcome (p=0.001; Hazard ratio=4.90). To confirm the effect of NM23-H1 on radiation-induced cytotoxicity, we generated several stable clones derived from a human HNSCC cell line (SAS) using knockdown and overexpression of NM23-H1. Knockdown of NM23-H1 decreased the radio-sensitivity of SAS cells, possibly associated with a decrease in the radiation-induced G2/M-phase accumulation and upregulation of cyclin B1. On the contrary, overexpression of NM23-H1 can reverse the aforementioned adverse results. Consequently, we suggest that NM23-H1 expression may be considered as a potential therapeutic treatment option for HNSCC patients.

18.
Antibiotics (Basel) ; 10(11)2021 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-34827316

RESUMEN

Drug efflux pumps are one of the major elements used by antibiotic-resistant bacteria. Efflux pump inhibitors (EPIs) are potential therapeutic agents for adjunctive therapy, which can restore the activity of antibiotics that are no longer effective against pathogens. This study evaluated the seaweed compound diphenylmethane (DPM) for its EPI activity. The IC50 and modulation results showed that DPM has no antibacterial activity but can potentiate the activity of antibiotics against drug-resistant E. coli. Time-kill studies reported that a combination of DPM and erythromycin exhibited greater inhibitory activity against drug-resistant Escherichia coli. Dye accumulation and dye efflux studies using Hoechst 33342 and ethidium bromide showed that the addition of DPM significantly increased dye accumulation and reduced dye efflux in drug-resistant E. coli, suggesting its interference with dye translocation by an efflux pump. Using MALDI-TOF, it was observed that the addition of DPM could continuously reduce antibiotic efflux in drug-resistant E. coli. Additionally, DPM did not seem to damage the E. coli membranes, and the cell toxicity test showed that it features mild human-cell toxicity. In conclusion, these findings showed that DPM could serve as a potential EPI for drug-resistant E. coli.

20.
Nat Commun ; 11(1): 4642, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32934200

RESUMEN

Epigenetic regulation plays an important role in governing stem cell fate and tumorigenesis. Lost expression of a key DNA demethylation enzyme TET2 is associated with human cancers and has been linked to stem cell traits in vitro; however, whether and how TET2 regulates mammary stem cell fate and mammary tumorigenesis in vivo remains to be determined. Here, using our recently established mammary specific Tet2 deletion mouse model, the data reveals that TET2 plays a pivotal role in mammary gland development and luminal lineage commitment. We show that TET2 and FOXP1 form a chromatin complex that mediates demethylation of ESR1, GATA3, and FOXA1, three key genes that are known to coordinately orchestrate mammary luminal lineage specification and endocrine response, and also are often silenced by DNA methylation in aggressive breast cancers. Furthermore, Tet2 deletion-PyMT breast cancer mouse model exhibits enhanced mammary tumor development with deficient ERα expression that confers tamoxifen resistance in vivo. As a result, this study elucidates a role for TET2 in governing luminal cell differentiation and endocrine response that underlies breast cancer resistance to anti-estrogen treatments.


Asunto(s)
Diferenciación Celular , Proteínas de Unión al ADN/metabolismo , Estradiol/metabolismo , Estrógenos/metabolismo , Glándulas Mamarias Animales/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/fisiopatología , Linaje de la Célula , Metilación de ADN , Proteínas de Unión al ADN/genética , Dioxigenasas , Sistema Endocrino/metabolismo , Epigénesis Genética , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Femenino , Humanos , Glándulas Mamarias Animales/fisiopatología , Ratones , Ratones Noqueados , Proteínas Proto-Oncogénicas/genética
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