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1.
Proc Natl Acad Sci U S A ; 120(16): e2216953120, 2023 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-37036972

RESUMEN

In cancer cells, endogenous or therapy-induced DNA damage leads to the abnormal presence of DNA in the cytoplasm, which triggers the activation of cGAS (cyclic GMP-AMP synthase) and STING (stimulator of interferon genes). STAT2 suppresses the cGAMP-induced expression of IRF3-dependent genes by binding to STING, blocking its intracellular trafficking, which is essential for the full response to STING activation. STAT2 reshapes STING signaling by inhibiting the induction of IRF3-dependent, but not NF-κB-dependent genes. This noncanonical activity of STAT2 is regulated independently of its tyrosine phosphorylation but does depend on the phosphorylation of threonine 404, which promotes the formation of a STAT2:STING complex that keeps STING bound to the endoplasmic reticulum (ER) and increases resistance to DNA damage. We conclude that STAT2 is a key negative intracellular regulator of STING, a function that is quite distinct from its function as a transcription factor.


Asunto(s)
Proteínas de la Membrana , Nucleotidiltransferasas , Proteínas Serina-Treonina Quinasas , Factor de Transcripción STAT2 , ADN/metabolismo , Daño del ADN , Nucleotidiltransferasas/metabolismo , Fosforilación , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Factor de Transcripción STAT2/metabolismo , Proteínas de la Membrana/metabolismo
2.
BMC Neurol ; 24(1): 206, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886633

RESUMEN

BACKGROUND: Mutations in the SLC5A7 gene cause congenital myasthenia, a rare genetic disorder. Mutation points in the SLC5A7 gene differ among individuals and encompass various genetic variations; however, exon deletion variants have yet to be reported in related cases. This study aims to explore the clinical phenotype and genetic traits of a patient with congenital myasthenic syndrome due to SLC5A7 gene variation and those of their family members. CASE PRESENTATION: We describe a case of a Chinese male with congenital myasthenic syndrome presenting fluctuating limb weakness. Genetic testing revealed a heterozygous deletion mutation spanning exons 1-9 in the SLC5A7 gene. QPCR confirmed a deletion in exon 9 of the SLC5A7 gene in the patient's mother and brother. Clinical symptoms of myasthenia improved following treatment with pyridostigmine. CONCLUSION: Exons 1, 5, and 9 of the SLC5A7 gene encode the choline transporter's transmembrane region. Mutations in these exons can impact the stability and plasma membrane levels of the choline transporter. Thus, a heterozygous deletion in exons 1-9 of the SLC5A7 gene could be the pathogenic cause for this patient. In patients exhibiting fluctuating weakness, positive RNS, and seronegativity for myasthenia gravis antibodies, a detailed family history should be considered, and enhanced genetic testing is recommended to determine the cause.


Asunto(s)
Síndromes Miasténicos Congénitos , Humanos , Síndromes Miasténicos Congénitos/genética , Síndromes Miasténicos Congénitos/diagnóstico , Masculino , Mutación , Linaje , Adulto , Pruebas Genéticas/métodos , Femenino , Simportadores/genética
3.
J Immunol ; 206(9): 2061-2074, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33827893

RESUMEN

The recently identified anion channel LRRC8 volume-regulated anion channels (VRACs) are heteromeric hexamers constituted with the obligate LRRC8A subunit paired with at least one of the accessory LRRC8B to LRRC8E subunits. In addition to transport chloride, taurine, and glutamate, LRRC8 VRACs also transport the anticancer agent cisplatin and STING agonists 2'3'-cyclic GMP-AMP (cGAMP) and cyclic dinucleotides; hence, they are implicated in a variety of physiological and pathological processes, such as cell swelling, stroke, cancer, and viral infection. Although the subunit composition largely determines VRAC substrate specificity, the opening of various VRAC pores under physiological and pathological settings remains enigmatic. In this study, we demonstrated that VRACs comprising LRRC8A and LRRC8E (LRRC8A/E-containing VRACs), specialized in cGAMP transport, can be opened by a protein component present in serum under resting condition. Serum depletion ablated the tonic activity of LRRC8A/E-containing VRACs, decreasing cGAMP transport in various human and murine cells. Also, heating or proteinase K treatment abolished the ability of serum to activate VRAC. Genetic analyses revealed a crucial role for cGAMP synthase (cGAS) in serum/TNF-promoted VRAC activation. Notably, the presence of cGAS on the plasma membrane, rather than its DNA-binding or enzymatic activity, enabled VRAC activation. Moreover, phospholipid PIP2 seemed to be instrumental in the membrane localization of cGAS and its association with VRACs. Corroborating a role for LRRC8A/D-containing VRACs in cisplatin transport, serum and TNF markedly potentiated cisplatin uptake and killing of cancer cells derived from human or mouse. Together, these observations provide new insights into the complex regulation of VRAC activation and suggest a novel approach to enhance the efficacy of cGAMP and cisplatin in treating infection and cancer.


Asunto(s)
Antineoplásicos/farmacología , Cisplatino/farmacología , Inflamación/tratamiento farmacológico , Proteínas de la Membrana/inmunología , Nucleótidos Cíclicos/farmacología , Animales , Antineoplásicos/inmunología , Cisplatino/inmunología , Inflamación/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Nucleótidos Cíclicos/inmunología
4.
Proc Natl Acad Sci U S A ; 117(26): 15047-15054, 2020 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-32532922

RESUMEN

Tamoxifen, a widely used modulator of the estrogen receptor (ER), targets ER-positive breast cancer preferentially. We used a powerful validation-based insertion mutagenesis method to find that expression of a dominant-negative, truncated form of the histone deacetylase ZIP led to resistance to tamoxifen. Consistently, increased expression of full-length ZIP gives the opposite phenotype, inhibiting the expression of genes whose products mediate resistance. An important example is JAK2 By binding to two specific sequences in the promoter, ZIP suppresses JAK2 expression. Increased expression and activation of JAK2 when ZIP is inhibited lead to increased STAT3 phosphorylation and increased resistance to tamoxifen, both in cell culture experiments and in a mouse xenograft model. Furthermore, data from human tumors are consistent with the conclusion that decreased expression of ZIP leads to resistance to tamoxifen in ER-positive breast cancer.


Asunto(s)
Neoplasias de la Mama/enzimología , Proteínas Quinasas Asociadas a Muerte Celular/metabolismo , Resistencia a Antineoplásicos , Janus Quinasa 2/metabolismo , Factor de Transcripción STAT3/metabolismo , Tamoxifeno/farmacología , Animales , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Proteínas Quinasas Asociadas a Muerte Celular/genética , Femenino , Humanos , Janus Quinasa 2/genética , Ratones , Ratones SCID , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Factor de Transcripción STAT3/genética
5.
Angew Chem Int Ed Engl ; 62(14): e202218669, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36762956

RESUMEN

Proton transfer is crucial for electrocatalysis. Accumulating cations at electrochemical interfaces can alter the proton transfer rate and then tune electrocatalytic performance. However, the mechanism for regulating proton transfer remains ambiguous. Here, we quantify the cation effect on proton diffusion in solution by hydrogen evolution on microelectrodes, revealing the rate can be suppressed by more than 10 times. Different from the prevalent opinions that proton transport is slowed down by modified electric field, we found water structure imposes a more evident effect on kinetics. FTIR test and path integral molecular dynamics simulation indicate that proton prefers to wander within the hydration shell of cations rather than to hop rapidly along water wires. Low connectivity of water networks disrupted by cations corrupts the fast-moving path in bulk water. This study highlights the promising way for regulating proton kinetics via a modified water structure.

6.
J Clin Lab Anal ; 36(7)2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35576496

RESUMEN

BACKGROUND: Osteosarcoma (OS) is the most common bone cancer mostly seen in people aged 10-25 years. This research aims to clarify the function of hsa_circ_0001982 in osteosarcoma (OS) and its effect on drug resistance, preliminarily exploring its mechanism. METHODS: The expression of hsa_circ_0001982 and miR-143 in OS clinical tissues and cells was detected by real-time fluorescence quantitative polymerase chain reaction (qRT-PCR), MTT, colony formation assay, and transwell assay assessed cell proliferation, colony formation, migration, and invasion, respectively. The targeted relationship of hsa_circ_0001982 and miR-143 was verified by a dual-luciferase reporter assay. RESULT: The expression of hsa_circ_0001982 was significantly increased in OS tissues and cells (MG63), as in well as chemoresistant OS tissues and cells (MG63/Dox). Overexpression of hsa_circ_0001982 promoted proliferation, colony formation, migration, invasion, and multidrug resistance in MG63 cells. By contrast, knockdown of hsa_circ_0001982 markedly reduced the resistance of MG63/Dox cells to doxorubicin (IC50 evidently reduced). Bioinformatic prediction showed that miR-143 was a target miRNA of hsa_circ_0001982, and a dual-luciferase reporter assay proved this. Further experiments revealed that miR-143 expression was notably downregulated in OS tissues, chemoresistant OS tissues, and MG63/Dox cells. Moreover, miR-143 was negatively correlated with hsa_circ_0001982 in OS cells and tissues. CONCLUSION: The regulation of malignant behaviors such as proliferation, invasion, migration, and multidrug resistance of OS cells by hsa_circ_0001982 may be achieved by targeting miR-143. Moreover, hsa_circ_0001982 is a potential target for early diagnosis and targeted therapy of OS.


Asunto(s)
Neoplasias Óseas , Resistencia a Antineoplásicos , MicroARNs , Osteosarcoma , ARN Circular , Neoplasias Óseas/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Resistencia a Múltiples Medicamentos/genética , Resistencia a Antineoplásicos/genética , Humanos , MicroARNs/genética , Invasividad Neoplásica/genética , Osteosarcoma/patología , ARN Circular/genética
7.
EMBO J ; 36(2): 202-212, 2017 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-27852626

RESUMEN

The transcription factor ISGF3, comprised of IRF9 and tyrosine-phosphorylated STATs 1 and 2, transmits the signal from the type I interferon receptor to the genome. We have discovered a novel phosphorylation of STAT2 on T387 that negatively regulates this response. In most untreated cell types, the majority of STAT2 is phosphorylated on T387 constitutively. In response to interferon-ß, the T387A mutant of STAT2 is much more effective than wild-type STAT2 in mediating the expression of many interferon-stimulated genes, in protecting cells against virus infection, and in inhibiting cell growth. Interferon-ß-treated cells expressing wild-type STAT2 contain much less ISGF3 capable of binding to an interferon-stimulated response element than do cells expressing T387A STAT2. T387 lies in a cyclin-dependent kinase (CDK) consensus sequence, and CDK inhibitors decrease T387 phosphorylation. Using CDK inhibitors to reverse the constitutive inhibitory phosphorylation of T387 of U-STAT2 might enhance the efficacy of type I interferons in many different clinical settings.


Asunto(s)
Factor 3 de Genes Estimulados por el Interferón/metabolismo , Interferón beta/metabolismo , Procesamiento Proteico-Postraduccional , Factor de Transcripción STAT2/metabolismo , Transducción de Señal , Línea Celular , Humanos , Modelos Biológicos , Fosforilación
8.
Helicobacter ; 26(5): e12840, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34390083

RESUMEN

BACKGROUND: The Maastricht V/Florence Consensus Report recommends amoxicillin-fluoroquinolone triple or quadruple therapy as a second-line treatment for Helicobacter pylori infection. An important caveat of amoxicillin-fluoroquinolone rescue therapy is poor eradication efficacy in the presence of fluoroquinolone resistance. The study aimed to investigate the efficacies of tetracycline-levofloxacin (TL) quadruple therapy and amoxicillin-levofloxacin (AL) quadruple therapy in the second-line treatment of H. pylori infection. METHODS: Consecutive H. pylori-infected subjects after the failure of first-line therapies were randomly allocated to receive either TL quadruple therapy (tetracycline 500 mg QID, levofloxacin 500 mg QD, esomeprazole 40 mg BID, and tripotassium dicitrato bismuthate 300 mg QID) or AL quadruple therapy (amoxicillin 500 mg QID, levofloxacin 500 mg QD, esomeprazole 40 mg BID, and tripotassium dicitrato bismuthate 300 mg QID) for 10 days. Post-treatment H. pylori status was assessed 6 weeks after the end of therapy. RESULTS: The study was early terminated after an interim analysis. In the TL quadruple group, 50 out of 56 patients (89.3%) had successful eradication of H. pylori infection. Cure of H. pylori infection was achieved only in 39 of 52 patients (69.6%) receiving AL quadruple therapy. Intention-to-treat analysis showed that TL quadruple therapy achieved a markedly higher eradication rate than AL quadruple therapy (95% confidence interval: 4.8% to 34.6%; p = 0.010). Further analysis revealed that TL quadruple therapy had a high eradication rate for both levofloxacin-susceptible and resistant strains (100% and 88.9%). In contrast, AL quadruple therapy yielded a high eradication for levofloxacin-susceptible strains (90.9%) but a poor eradication efficacy for levofloxacin-resistant strains (50.0%). The two therapies exhibited comparable frequencies of adverse events (37.5% vs 21.4%) and drug adherence (98.2% vs 94.6%). CONCLUSIONS: Ten-day TL quadruple therapy is more effective than AL quadruple therapy in the second-line treatment of H. pylori infection in a population with high levofloxacin resistance.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Amoxicilina/uso terapéutico , Antibacterianos/uso terapéutico , Quimioterapia Combinada , Infecciones por Helicobacter/tratamiento farmacológico , Humanos , Levofloxacino/uso terapéutico , Metronidazol/uso terapéutico , Inhibidores de la Bomba de Protones/uso terapéutico , Tetraciclina/uso terapéutico , Resultado del Tratamiento
9.
Cardiovasc Drugs Ther ; 35(5): 995-1002, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33030686

RESUMEN

PURPOSE: This meta-analysis compared the efficacy and safety of oral anticoagulation (OAC) therapy alone versus OAC plus single antiplatelet therapy (SAPT) in patients with an indication for chronic OAC (mostly due to atrial fibrillation) after transcatheter aortic valve implantation (TAVI). METHODS: A systematic literature search was performed in the PubMed, Embase, and Cochrane Library databases to identify relevant studies. Data was extracted from the eligible studies and outcomes expressed as relative risks (RRs) with 95% confidence intervals (CIs). RESULTS: Five studies comprising 1344 patients with an indication for chronic OAC and undergoing TAVI were included. Of the 1344 patients, 480 patients received OAC therapy alone and 864 patients received OAC plus SAPT. There were no significant differences between OAC alone versus OAC plus SAPT in all-cause mortality (RR = 1.05, 95% CI 0.84-1.30, p = 0.69) and ischemic stroke (RR = 0.95, 95% CI 0.95-1.61, p = 0.86). However, OAC alone was associated with significantly lower risks of all bleeding events (RR = 0.62, 95% CI 0.49-0.69, p < 0.0001) and major and/ life-threatening bleeding events (RR = 0.57, 95% CI 0.42-0.76, p = 0.0002) compared to OAC plus SAPT. CONCLUSION: In patients with an indication for chronic anticoagulation, post-TAVI antithrombotic therapy with OAC alone compared to OAC plus SAPT may be not significantly different in reducing all-cause mortality and ischemic stroke, but has an important benefit in a significantly lower risk of all bleeding and major and/life-threatening bleeding events.


Asunto(s)
Anticoagulantes/uso terapéutico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Reemplazo de la Válvula Aórtica Transcatéter/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Anticoagulantes/administración & dosificación , Anticoagulantes/efectos adversos , Terapia Antiplaquetaria Doble , Femenino , Hemorragia/inducido químicamente , Humanos , Accidente Cerebrovascular Isquémico/prevención & control , Masculino , Estudios Observacionales como Asunto , Inhibidores de Agregación Plaquetaria/administración & dosificación , Inhibidores de Agregación Plaquetaria/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto
10.
BMC Cardiovasc Disord ; 21(1): 72, 2021 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-33541271

RESUMEN

BACKGROUND: Left ventricular negative remodelling after ST-segment elevation myocardial infarction (STEMI) is considered as the major cause for the poor prognosis. But the predisposing factors and potential mechanisms of left ventricular negative remodelling after STEMI remain not fully understood. The present research mainly assessed the association between the stress hyperglycaemia ratio (SHR) and left ventricular negative remodelling. METHODS: We recruited 127 first-time, anterior, and acute STEMI patients in the present study. All enrolled patients were divided into 2 subgroups equally according to the median value of SHR level (1.191). Echocardiography was conducted within 24 h after admission and 6 months post-STEMI to measure left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDD), and left ventricular end-systolic diameter (LVESD). Changes in echocardiography parameters (δLVEF, δLVEDD, δLVESD) were calculated as LVEF, LVEDD, and LVESD at 6 months after infarction minus baseline LVEF, LVEDD and LVESD, respectively. RESULTS: In the present study, the mean SHR was 1.22 ± 0.25 and there was significant difference in SHR between the 2 subgroups (1.05 (0.95, 1.11) vs 1.39 (1.28, 1.50), p < 0.0001). The global LVEF at 6 months post-STEMI was significantly higher in the low SHR group than the high SHR group (59.37 ± 7.33 vs 54.03 ± 9.64, p = 0.001). Additionally, the global LVEDD (49.84 ± 5.10 vs 51.81 ± 5.60, p = 0.040) and LVESD (33.27 ± 5.03 vs 35.38 ± 6.05, p = 0.035) at 6 months after STEMI were lower in the low SHR group. Most importantly, after adjusting through multivariable linear regression analysis, SHR remained associated with δLVEF (beta = -9.825, 95% CI -15.168 to -4.481, p < 0.0001), δLVEDD (beta = 4.879, 95% CI 1.725 to 8.069, p = 0.003), and δLVESD (beta = 5.079, 95% CI 1.421 to 8.738, p = 0.007). CONCLUSIONS: In the present research, we demonstrated for the first time that SHR is significantly correlated with left ventricular negative remodelling after STEMI.


Asunto(s)
Infarto de la Pared Anterior del Miocardio/fisiopatología , Glucemia/metabolismo , Hiperglucemia/sangre , Infarto del Miocardio con Elevación del ST/fisiopatología , Función Ventricular Izquierda , Remodelación Ventricular , Adulto , Anciano , Infarto de la Pared Anterior del Miocardio/diagnóstico por imagen , Infarto de la Pared Anterior del Miocardio/terapia , Biomarcadores/sangre , Ecocardiografía , Femenino , Humanos , Hiperglucemia/diagnóstico , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea , Medición de Riesgo , Factores de Riesgo , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/terapia , Factores de Tiempo , Resultado del Tratamiento
11.
Proc Natl Acad Sci U S A ; 115(15): 3906-3911, 2018 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-29581268

RESUMEN

In response to IFNß, the IL6 gene is activated, modestly at early times by ISGF3 (IRF9 plus tyrosine-phosphorylated STATs 1 and 2), and strongly at late times by U-ISGF3 (IRF9 plus U-STATs 1 and 2, lacking tyrosine phosphorylation). A classical IFN-stimulated response element (ISRE) at -1,513 to -1,526 in the human IL6 promoter is required. Pretreating cells with IFNß or increasing the expression of U-STAT2 and IRF9 exogenously greatly enhances IL6 expression in response to the classical NF-κB activators IL1, TNF, and LPS. U-STAT2 binds tightly to IRF9, the DNA binding subunit of ISGF3, and also to the p65 subunit of NF-κB. Therefore, as shown by ChIP analyses, U-STAT2 can bridge the ISRE and κB elements in the IL6 promoter. In some cancer cells, the protumorigenic activation of STAT3 will be enhanced by the increased synthesis of IL6 that is facilitated by high expression of U-STAT2 and IRF9.


Asunto(s)
Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón/metabolismo , Interleucina-6/genética , FN-kappa B/metabolismo , Factor de Transcripción STAT2/metabolismo , Regulación de la Expresión Génica , Humanos , Interferón beta/genética , Interferón beta/metabolismo , Interleucina-6/metabolismo , FN-kappa B/genética , Fosforilación , Regiones Promotoras Genéticas , Elementos de Respuesta , Factor de Transcripción STAT2/genética , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Regulación hacia Arriba
12.
J Med Syst ; 45(1): 9, 2021 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-33404890

RESUMEN

The coronavirus disease 2019 (COVID-19), which is caused by a novel coronavirus (SARS-COV-2), has compromised health care systems and normal management of patients with cardiovascular diseases [1-3]. Patients with non-communicable diseases, including acute myocardial infarction (AMI) are vulnerable to this stress [4, 5]. Acute ST segment elevation myocardial infarction (STEMI), the most critical type of AMI, is associated with high mortality even with modern medicine [6-8]. Timely reperfusion therapy is critical for STEMI patients because a short ischemia time is associated with better clinical outcomes and lower acute and long -term mortality [9-12]. The COVID-19 pandemic placed the management of STEMI patients in a difficult situation due to the need to balance timely reperfusion therapy and maintaining strict infection control practices [13, 14]. Telemedicine, which is used to deliver health care services using information or communication technology, provides an opportunity to carry out the evaluation, diagnosis, and even monitor the patients after discharge when social distancing is needed [15]. In this article, we reported our preliminary experience with the usefulness of telemedicine in managing STEMI patients during the COVID-19 pandemic. We also provided a review of this topic.


Asunto(s)
COVID-19/terapia , Infarto del Miocardio con Elevación del ST/terapia , Telemedicina/métodos , COVID-19/complicaciones , Manejo de la Enfermedad , Femenino , Humanos , Masculino , Atención al Paciente/métodos , Medición de Riesgo , Infarto del Miocardio con Elevación del ST/diagnóstico
13.
Emerg Infect Dis ; 26(11): 2755-2758, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32667282

RESUMEN

During January-February 2020, coronavirus disease (COVID-19) and tuberculosis were diagnosed for 3 patients in Wuhan, China. All 3 patients had COVID-19 pneumonia. One severely ill patient died after acute respiratory distress syndrome developed. Clinicians and public health officials should be aware of underlying chronic infections such as tuberculosis in COVID-19 patients.


Asunto(s)
Betacoronavirus , Coinfección/microbiología , Infecciones por Coronavirus/microbiología , Mycobacterium , Neumonía Viral/microbiología , Tuberculosis Pulmonar/microbiología , Adulto , COVID-19 , China , Resultado Fatal , Humanos , Masculino , Persona de Mediana Edad , Pandemias , SARS-CoV-2
14.
Invest New Drugs ; 38(4): 1003-1011, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31612426

RESUMEN

The Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathway plays a vital role in immunity, cell division, cell death and tumor formation. Disrupted JAK-STAT signaling may lead to various diseases, especially cancer and immune disorders. Because of its importance, this signaling pathway has received significant attention from the pharmaceutical and biotechnology industries as a therapeutic target for drug design. However, few JAK or STATs inhibitors have been developed for cancer treatment. We used an in vitro STAT3 luciferase reporter assay to find novel inhibitors that could effectively block the JAK-STAT pathway. In our study, we screened 16,081 drug-like chemicals and found that atopaxar hydrobromide (AHB) is a specific inhibitor of JAK-STAT3 signaling. Our results suggest that AHB not only blocks constitutively activated and cytokine-induced STAT3 phosphorylation but also inhibits JAK1 and JAK2 phosphorylation. Moreover, AHB induces G1 phase cell cycle arrest, which stops cancer cell growth and induces apoptosis. AHB also inhibited tumor cell growth in vivo. In conclusion, AHB is a potential inhibitor that could be developed as a JAK-STAT pathway drug.


Asunto(s)
Antineoplásicos/farmacología , Iminas/farmacología , Janus Quinasa 1/antagonistas & inhibidores , Janus Quinasa 2/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Piridinas/farmacología , Factor de Transcripción STAT3/antagonistas & inhibidores , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Citocinas/farmacología , Humanos , Janus Quinasa 1/metabolismo , Janus Quinasa 2/metabolismo , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Fosforilación/efectos de los fármacos , Factor de Transcripción STAT3/metabolismo
15.
Q J Nucl Med Mol Imaging ; 64(4): 393-399, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30160089

RESUMEN

BACKGROUND: 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography (18F-FDG PET) has the potential to detect various types of cancers, including thyroid cancer (TC), at a potentially curable stage. Increased uptake of 18F-FDG was observed in anaplastic and poorly differentiated thyroid cancer cells, and PET-positive tumors are more likely to be resistant to 131I treatment. As cancer stem cells (CSCs) possess a dedifferentiated phenotype and are resistant to many anticancer therapies, we hypothesized that the expression of CSC-related markers is correlated with the ability of tumor cells in TC to uptake FDG. METHODS: The present study cohort included 12 patients with TC, who underwent 18F-FDG PET/CT imaging before surgery. Quantitative polymerase chain reaction (QPCR) and immunohistochemical (IHC) staining were performed to analyze the expression patterns of gene markers related to embryonic stem (ES) cells and CSCs in TC. RESULTS: The mRNA expression levels of CSC- (CD133 and CD44) and ES-related genes (Oct4 and Nanog) were higher in TC tissue than in normal thyroid tissue, whereas the mRNA expression levels of thyroid-specific genes (Tg, TSHR, and TTF1) were higher in normal thyroid tissue than in TC tissue. There was a positive and statistically significant correlation between FDG uptake (SUVmax) of tumor and relative mRNA levels of CD133, CD44, Oct4, and Nanog. The IHC results demonstrated that CD133 and Nanog were expressed in TC tissue but not in normal thyroid tissue, however, CD44 expression was observed in both TC and normal thyroid tissue. Comparisons of the clinicopathological parameters between TC tissues with low and high SUVmax demonstrated significant differences in protein level of CD133 but not in that of Nanog. CONCLUSIONS: The pre-therapeutic tumor SUVmax obtained from 18F-FDG PET/CT may be a potential predictor for evaluating the proportion of CSC population in individual patients with TC.


Asunto(s)
Fluorodesoxiglucosa F18/química , Células Madre Neoplásicas/efectos de la radiación , Radiofármacos/química , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/tratamiento farmacológico , Antígeno AC133/metabolismo , Transporte Biológico , Diferenciación Celular/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Fluorodesoxiglucosa F18/farmacología , Humanos , Receptores de Hialuranos/metabolismo , Radioisótopos de Indio/química , Tomografía Computarizada por Tomografía de Emisión de Positrones , ARN Mensajero , Receptores de Tirotropina/metabolismo , Glándula Tiroides/citología , Distribución Tisular , Tomografía Computarizada por Rayos X , Factor Trefoil-1/metabolismo
16.
J Gastroenterol Hepatol ; 35(10): 1731-1737, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32167605

RESUMEN

BACKGROUND AND AIM: Concomitant therapy is a recommended first-line treatment for Helicobacter pylori infection in most national or international consensuses. Reverse hybrid therapy is a modified 14-day concomitant therapy without clarithromycin and metronidazole in the final 7 days. This study aims to test whether 14-day reverse hybrid therapy is non-inferior to 14-day concomitant therapy in the first-line treatment of H. pylori infection. METHODS: Helicobacter pylori-infected adult patients were randomly assigned to receive either reverse hybrid therapy (dexlansoprazole 60 mg o.d. plus amoxicillin 1 g b.d. for 14 days, and clarithromycin 500 mg plus metronidazole 500 mg b.d. for initial 7 days) or concomitant therapy (dexlansoprazole 60 mg once o.d. plus amoxicillin 1 g, clarithromycin 500 mg, and metronidazole 500 mg b.d. for 14 days). H. pylori status was assessed 6 weeks after the end of treatment. RESULTS: Helicobacter pylori-infected participants (n = 248) were randomized to receive either 14-day reverse hybrid therapy (n = 124) or 14-day concomitant therapy (n = 124). Intention-to-treat analysis demonstrated that the two therapies had comparable eradication rate (95.2% vs 93.5%; 95% confidence interval, -4.0% to 7.4%; P = 0.582). However, reverse hybrid therapy had a much lower frequency of adverse events than concomitant therapy (20.2% vs 38.7%, P = 0.001). The two therapies exhibited comparable drug adherence (93.5% vs 87.9%, P = 0.125). CONCLUSIONS: Fourteen-day reverse hybrid therapy and 14-day concomitant therapy are equivalent in efficacy for the first-line treatment of H. pylori infection. However, reverse hybrid therapy has fewer adverse events compared with concomitant therapy.


Asunto(s)
Amoxicilina/administración & dosificación , Antibacterianos/administración & dosificación , Claritromicina/administración & dosificación , Dexlansoprazol/administración & dosificación , Gastritis/tratamiento farmacológico , Gastritis/microbiología , Infecciones por Helicobacter , Helicobacter pylori , Metronidazol/administración & dosificación , Adulto , Anciano , Amoxicilina/efectos adversos , Antibacterianos/efectos adversos , Claritromicina/efectos adversos , Dexlansoprazol/efectos adversos , Esquema de Medicación , Quimioterapia Combinada/métodos , Femenino , Humanos , Masculino , Metronidazol/efectos adversos , Persona de Mediana Edad , Resultado del Tratamiento
17.
Med Sci Monit ; 26: e927061, 2020 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-32938901

RESUMEN

BACKGROUND The efficacy of telemedicine in reducing delay times and short-term adverse clinical outcomes in patients with ST segment elevation myocardial infarction (STEMI) during the coronavirus disease 2019 (COVID-19) pandemic is unclear. This study compared outcomes in patients with STEMI who had percutaneous coronary intervention (PCI) and the use of a telemedicine app from August 2019 to March 2020 at a single center in Beijing, China. MATERIAL AND METHODS A total of 243 patients with STEMI who underwent PCI were consecutively enrolled and divided into 2 groups according to the date, before or after the pandemic. The 2 groups were further divided into patients who used the app for consulting and those who did not. RESULTS The time from symptom onset to calling an ambulance (SCT), door to balloon time (DTB), and total ischemia time (TIT) were significantly prolonged in patients after the pandemic. Patients who used the app had shorter SCT, DTB, and TIT before and after the pandemic compared to those who did not. Adverse clinical outcomes were significantly higher after compared with before the pandemic, despite the incidence rate of stroke, any revascularization, and stent thrombosis. However, there was no significant difference in short-term adverse clinical outcomes between patients who used the app and those who did not before and after the pandemic. CONCLUSIONS Telemedicine reduced the delay time of STEMI patients during the COVID-19 pandemic. The difference in short-term adverse clinical outcomes was not statistically significant between patients who used the app and those who did not.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/epidemiología , Aplicaciones Móviles , Pandemias , Intervención Coronaria Percutánea , Neumonía Viral/epidemiología , Infarto del Miocardio con Elevación del ST/terapia , Telemedicina , Anciano , COVID-19 , China/epidemiología , Terapia Combinada , Comorbilidad , Angiografía Coronaria , Femenino , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , SARS-CoV-2 , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/tratamiento farmacológico , Infarto del Miocardio con Elevación del ST/epidemiología , Teléfono Inteligente , Telemedicina/métodos , Factores de Tiempo , Tiempo de Tratamiento , Resultado del Tratamiento
18.
Molecules ; 25(10)2020 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-32423116

RESUMEN

Citrus huanglongbing (HLB) is a destructive disease that causes significant damage to many citrus producing areas worldwide. To date, no strategy against this disease has been established. Inosine 5'-monophosphate dehydrogenase (IMPDH) plays crucial roles in the de novo synthesis of guanine nucleotides. This enzyme is used as a potential target to treat bacterial infection. In this study, the crystal structure of a deletion mutant of CLas IMPDHΔ98-201 in the apo form was determined. Eight known bioactive compounds were used as ligands for molecular docking. The results showed that bronopol and disulfiram bound to CLas IMPDHΔ98-201 with high affinity. These compounds were tested for their inhibition against CLas IMPDHΔ98-201 activity. Bronopol and disulfiram showed high inhibition at nanomolar concentrations, and bronopol was found to be the most potent molecule (Ki = 234 nM). The Ki value of disulfiram was 616 nM. These results suggest that bronopol and disulfiram can be considered potential candidate agents for the development of CLas inhibitors.


Asunto(s)
Antibacterianos/química , Proteínas Bacterianas/química , Disulfiram/química , Inhibidores Enzimáticos/química , IMP Deshidrogenasa/química , Glicoles de Propileno/química , Antibacterianos/metabolismo , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/metabolismo , Sitios de Unión , Citrus/efectos de los fármacos , Citrus/microbiología , Clonación Molecular , Cristalografía por Rayos X , Disulfiram/metabolismo , Inhibidores Enzimáticos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , IMP Deshidrogenasa/antagonistas & inhibidores , IMP Deshidrogenasa/metabolismo , Cinética , Liberibacter/enzimología , Liberibacter/genética , Liberibacter/patogenicidad , Ligandos , Simulación del Acoplamiento Molecular , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/terapia , Glicoles de Propileno/metabolismo , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidad por Sustrato , Termodinámica
19.
J Environ Sci (China) ; 87: 260-271, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31791499

RESUMEN

An embedded reservoir that provides an efficient nutrient removal system protects drinking water. However, embedded reservoirs are rarely used in eutrophic shallow lakes because of their undetermined nutrient retention efficiency and unknown effects by the phytoplankton community. In this study, we aim to investigate the nutrient retention and algae succession in an embedded reservoir and adjacent wetland from April 2017 to September 2018 in the eastern part of Lake Taihu, China. More than 40% of total phosphorus (TP) and 45% of particulate phosphorous entering the reservoir were retained semi-annually, and the highest TP removal efficiency was achieved in the reservoir during autumn with an average value of 53.3% ±â€¯9.9%. The overall nitrogen retention efficiency (21.7% ±â€¯37.8%) was lower than that of TP (41.8% ±â€¯27.8%). Similar trends were obtained in the wetland area. An important pathway for phosphorus removal is through particulate matter retention. Our study revealed that nutrient retention mechanisms in the reservoir were primarily via macrophyte absorption, particulate substance sedimentation, and prolonged water residence time. Consequently, the phytoplankton biomass (Chl-a) in the reservoir decreased (from 48.0 to 25.2 µg/L) and water transparency improved, due to the decreased P level and transformation of the phytoplankton group into simple structures with good ecological status. Therefore, the combination of embedded reservoir and constructed wetland ecosystem can be used successfully to protect surface water. The results will be advantageous to groups seeking to preserve drinking water sources.


Asunto(s)
Agua Potable , Monitoreo del Ambiente , Humedales , Biodegradación Ambiental , China , Ecosistema , Lagos/química , Nitrógeno/análisis , Fósforo/análisis , Fitoplancton
20.
Mol Cell Biochem ; 461(1-2): 119-126, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31359244

RESUMEN

Transforming growth factor beta is a key cytokine involved in the pathogenesis of fibrosis in many organs, whereas interleukin-6 plays an important role in the regulation of inflammation. They are both potent angiogenesis inducers with opposite effects on cell survival and apoptosis. TGF-ß2 induces apoptosis; in contrast, IL-6 protects cells from apoptosis. The possible interaction between these two cytokines is indicated in various disease states. In this study, we have assessed the effect of TGF-ß2 on IL-6 signaling and found that TGF-ß2 could strongly inhibit IL-6-induced STAT3 activation and synergy with IL-6 resulting in enhanced SOCS3 expression. Interestingly, IL-6 also slows down the decay of TGF-ß2 mRNA. Consistent with this mechanism, we found that TGF-ß2 could antagonize IL-6 effect on cell survival in both γ-irradiation and UV light-induced apoptosis. Taken together, the finding shows that TGF-ß2 serves as a negative regulator of IL-6 signaling and antagonizes the anti-apoptosis effect of IL-6.


Asunto(s)
Interleucina-6/metabolismo , Factor de Crecimiento Transformador beta2/metabolismo , Supervivencia Celular , Regulación hacia Abajo , Humanos , Estabilidad del ARN , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factor de Transcripción STAT3/metabolismo , Proteína 3 Supresora de la Señalización de Citocinas/metabolismo , Factor de Crecimiento Transformador beta2/antagonistas & inhibidores , Factor de Crecimiento Transformador beta2/genética , Regulación hacia Arriba
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