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1.
Nano Converg ; 11(1): 14, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622355

RESUMEN

Tunability of interfacial effects between two-dimensional (2D) crystals is crucial not only for understanding the intrinsic properties of each system, but also for designing electronic devices based on ultra-thin heterostructures. A prerequisite of such heterostructure engineering is the availability of 2D crystals with different degrees of interfacial interactions. In this work, we report a controlled epitaxial growth of monolayer TaSe2 with different structural phases, 1H and 1 T, on a bilayer graphene (BLG) substrate using molecular beam epitaxy, and its impact on the electronic properties of the heterostructures using angle-resolved photoemission spectroscopy. 1H-TaSe2 exhibits significant charge transfer and band hybridization at the interface, whereas 1 T-TaSe2 shows weak interactions with the substrate. The distinct interfacial interactions are attributed to the dual effects from the differences of the work functions as well as the relative interlayer distance between TaSe2 films and BLG substrate. The method demonstrated here provides a viable route towards interface engineering in a variety of transition-metal dichalcogenides that can be applied to future nano-devices with designed electronic properties.

2.
Rep Prog Phys ; 87(4)2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38518359

RESUMEN

Charge density wave (CDW is one of the most ubiquitous electronic orders in quantum materials. While the essential ingredients of CDW order have been extensively studied, a comprehensive microscopic understanding is yet to be reached. Recent research efforts on the CDW phenomena in two-dimensional (2D) materials provide a new pathway toward a deeper understanding of its complexity. This review provides an overview of the CDW orders in 2D with atomically thin transition metal dichalcogenides (TMDCs) as the materials platform. We mainly focus on the electronic structure investigations on the epitaxially grown TMDC samples with angle-resolved photoemission spectroscopy and scanning tunneling microscopy/spectroscopy as complementary experimental tools. We discuss the possible origins of the 2D CDW, novel quantum states coexisting with them, and exotic types of charge orders that can only be realized in the 2D limit.

3.
Foods ; 13(5)2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38472749

RESUMEN

Research on the comprehensive utilization of sour jujube and its beneficial properties to human health has attracted extensive attention. This study aims to conduct a bibliometric analysis of the bioactive profile of sour jujube and future trends in applications. The research advancements within this field from 2000 to 2023 were addressed using the Web of Science database and VOSviewer. Among the 322 results, the most frequent keywords of bioactivity are flavonoids, antioxidants, saponins, insomnia, polyphenols, terpenoids and anti-inflammatory; the most studied parts of sour jujube are seeds, fruits and leaves; the published articles with high citations mainly focus on identification, biological effects and different parts distribution of bioactive compounds. The bioactivity of various parts of sour jujube was reviewed considering their application potential. The seeds, rich in flavonoids, saponins and alkaloids, exhibit strong effects on central nervous system diseases and have been well-developed in pharmacology, healthcare products and functional foods. The pulp has antioxidant properties and is used to develop added-value foods (e.g., juice, vinegar, wine). The leaves can be used to make tea and flowers are good sources of honey; their extracts are rich sources of flavonoids and saponins, which show promising medicinal effects. The branches, roots and bark have healing properties in traditional folk medicine. Overall, this study provides a reference for future applications of sour jujube in food and medicine fields.

4.
Res Sq ; 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38464103

RESUMEN

Acute myocardial infarction stands as a prominent cause of morbidity and mortality worldwide1-6. Clinical studies have demonstrated that the severity of cardiac injury following myocardial infarction exhibits a circadian pattern, with larger infarct sizes and poorer outcomes in patients experiencing morning onset myocardial infarctions7-14. However, the molecular mechanisms that govern circadian variations of myocardial injury remain unclear. Here, we show that BMAL114-20, a core circadian transcription factor, orchestrates diurnal variability in myocardial injury. Unexpectedly, BMAL1 modulates circadian-dependent cardiac injury by forming a transcriptionally active heterodimer with a non-canonical partner, hypoxia-inducible factor 2 alpha (HIF2A)6,21-23, in a diurnal manner. Substantiating this finding, we determined the cryo-EM structure of the BMAL1/HIF2A/DNA complex, revealing a previously unknown capacity for structural rearrangement within BMAL1, which enables the crosstalk between circadian rhythms and hypoxia signaling. Furthermore, we identified amphiregulin (AREG) as a rhythmic transcriptional target of the BMAL1/HIF2A heterodimer, critical for regulating circadian variations of myocardial injury. Finally, pharmacologically targeting the BMAL1/HIF2A-AREG pathway provides effective cardioprotection, with maximum efficacy when aligned with the pathway's circadian trough. Our findings not only uncover a novel mechanism governing the circadian variations of myocardial injury but also pave the way for innovative circadian-based treatment strategies, potentially shifting current treatment paradigms for myocardial infarction.

5.
Front Immunol ; 15: 1328565, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38312838

RESUMEN

The human respiratory and circulatory systems collaborate intricately to ensure oxygen delivery to all cells, which is vital for ATP production and maintaining physiological functions and structures. During limited oxygen availability, hypoxia-inducible factors (HIFs) are stabilized and play a fundamental role in maintaining cellular processes for hypoxia adaptation. First discovered during investigations of erythropoietin production regulation, HIFs influence physiological and pathological processes, including development, inflammation, wound healing, and cancer. HIFs promote extracellular adenosine signaling by enhancing adenosine generation and receptor signaling, representing an endogenous feedback mechanism that curbs excessive inflammation, supports injury resolution, and enhances hypoxia tolerance. This is especially important for conditions that involve tissue hypoxia, such as acute respiratory distress syndrome (ARDS), which globally poses significant health challenges without specific treatment options. Consequently, pharmacological strategies to amplify HIF-mediated adenosine production and receptor signaling are of great importance.


Asunto(s)
Adenosina , Síndrome de Dificultad Respiratoria , Humanos , Hipoxia/patología , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Inflamación , Oxígeno
6.
Nat Mater ; 23(4): 470-478, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38418924

RESUMEN

Two-dimensional materials have emerged as an important research frontier for overcoming the challenges in nanoelectronics and for exploring new physics. Among them, black phosphorus, with a combination of a tunable bandgap and high mobility, is one of the most promising systems. In particular, black phosphorus nanoribbons show excellent electrostatic gate control, which can mitigate short-channel effects in nanoscale transistors. Controlled synthesis of black phosphorus nanoribbons, however, has remained an outstanding problem. Here we report large-area growth of black phosphorus nanoribbons directly on insulating substrates. We seed the chemical vapour transport growth with black phosphorus nanoparticles and obtain uniform, single-crystal nanoribbons oriented exclusively along the [100] crystal direction. With comprehensive structural calculations, we discover that self-passivation at the zigzag edges holds the key to the preferential one-dimensional growth. Field-effect transistors based on individual nanoribbons exhibit on/off ratios up to ~104, confirming the good semiconducting behaviour of the nanoribbons. These results demonstrate the potential of black phosphorus nanoribbons for nanoelectronic devices and also provide a platform for investigating the exotic physics in black phosphorus.

7.
J Biomol Struct Dyn ; : 1-12, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38174383

RESUMEN

Acquired resistance to EGFR is a major impediment in lung cancer treatment, highlighting the urgent need to discover novel compounds to overcome EGFR drug resistance. In this study, we utilized in silico methods and bioactivity evaluation for drug discovery to identify novel active anticancer agents targeting EGFRT790M/L858R and EGFRT790M/C797S/L858R. Firstly, we employed ROC-guided machine learning to retrieve nearly 7,765 compounds from a collection of three libraries (comprising over 220,000 compounds). Next, virtual screening, cluster analysis, and binding model analysis were employed to identify six potential compounds. Additionally, the kinase assay revealed that these six compounds demonstrated higher sensitivity to EGFR than c-Met. Among these compounds, T6496 inhibited both EGFRT790M/L858R and EGFRT790M/C797S/L858R kinases, with an IC50 of 3.30 and 8.72 µM. Furthermore, we evaluated the antitumor effects of the six selected compounds, and compound T6496 exhibited the strongest anticancer activity against H1975 cell lines, with an IC50 value of 2.7 µM. These results suggest that T6496 may mitigate EGFR resistance caused by T790M or C797S mutations. Moreover, the AO staining assay, JC-1 staining, ROS experiment and hemolytic toxicity evaluation revealed that T6496 could induce apoptosis in H1975 cell lines in a time-dependent and concentration-dependent manner, and is a potential compound for further structural optimization.Communicated by Ramaswamy H. Sarma.


ROC guided machine learning, virtual screening and bioevaluation was applied to discover six hit compounds for overcoming EGFR resistance mediated by T790M or C797S.The promising compound T6496 could both inhibit EGFRT790M/L858R and EGFRT790M/C797S/L858R, with an IC50 of 3.30 and 8.72 µM.In addition, T6496 and AO-365/43489452 show excellent anticancer activity even better than AZD9291.AO staining assay, JC-1 staining, and ROS experiment revealed that compounds T6496 could induce apoptosis in H1975 cell lines in a time-dependent and concentration-dependent manner.

8.
Nat Rev Drug Discov ; 23(3): 175-200, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38123660

RESUMEN

Hypoxia-inducible factors (HIFs) are highly conserved transcription factors that are crucial for adaptation of metazoans to limited oxygen availability. Recently, HIF activation and inhibition have emerged as therapeutic targets in various human diseases. Pharmacologically desirable effects of HIF activation include erythropoiesis stimulation, cellular metabolism optimization during hypoxia and adaptive responses during ischaemia and inflammation. By contrast, HIF inhibition has been explored as a therapy for various cancers, retinal neovascularization and pulmonary hypertension. This Review discusses the biochemical mechanisms that control HIF stabilization and the molecular strategies that can be exploited pharmacologically to activate or inhibit HIFs. In addition, we examine medical conditions that benefit from targeting HIFs, the potential side effects of HIF activation or inhibition and future challenges in this field.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Neoplasias , Humanos , Hipoxia/tratamiento farmacológico , Hipoxia/metabolismo , Factores de Transcripción , Neoplasias/tratamiento farmacológico , Oxígeno
9.
Comput Biol Chem ; 108: 108006, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38142532

RESUMEN

Due to antibiotic overuse, many bacteria have developed resistance, creating an urgent need for novel antimicrobial agents. It has been established that the filamentous temperature-sensitive mutant Z (FtsZ) of the bacterial cell division protein is an effective and promising antibacterial target. In this study, the optimal proteins were assessed by early recognition ability and the processed compound libraries were virtually screened using Vina. This effort resulted in the identification of 14 potentially active antimicrobial compounds. Among them, the compound T5S1607 demonstrated remarkable antibacterial efficacy against Bacillus subtilis ATCC9732 (MIC = 1 µg/mL) and Staphylococcus aureus ATC5C6538 (MIC = 4 µg/mL). Furthermore, in vitro experiments demonstrated that the selected compound T5S1607 rapidly killed bacteria and induced FtsZ protein aggregation, preventing bacterial division and leading to bacterial death. Additionally, cell toxicity and hemolysis experiments indicate that compound T5S1607 exhibits minimal toxicity to LO2 cells and shows no significant hemolytic effects on mammalian cells in vitro at the MIC concentration range. All the results indicate that compound T5S1607 is a promising antibacterial agent and a potential FtsZ inhibitor. In conclusion, this work successfully discovered FtsZ inhibitors with good activity through the virtual screening drug discovery process.


Asunto(s)
Proteínas Bacterianas , Proteínas del Citoesqueleto , Animales , Proteínas Bacterianas/metabolismo , Antibacterianos/farmacología , Bacterias , Descubrimiento de Drogas , Pruebas de Sensibilidad Microbiana , Mamíferos/metabolismo
10.
Front Public Health ; 11: 1243642, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37841716

RESUMEN

Introduction: The provincial malaria diagnosis reference laboratories review and assess malaria cases diagnosed in health facilities for supporting the malaria elimination efforts and preventing re-transmission of imported malaria. The study aimed to evaluate the detection capability of malaria diagnosis in China from 2014 to 2021. Methods: Data on malaria cases reported in the provincial-level administrative divisions (PLADs) of Anhui, Henan, Hubei, Guangxi, and Zhejiang from 2014 to 2021 were collected and analyzed. Results: In total, 5,770 malaria cases were reported from 2014 to 2021, and 99.05% (5,715/5,770) were submitted to the provincial malaria diagnosis reference laboratories. The median time between malaria cases being reported and the samples being received by reference laboratories was 6 days (Interquartile range, IQR:3-12 days) from 2017 to 2021. Diagnosis of 5,680 samples in the laboratory were confirmed by provincial reference laboratories, including 3,970 cases of Plasmodium falciparum, 414 of P. vivax, 1,055 of P. ovale, 158 of P. malariae, 1 of P. knowlesi, and 82 of mixed infections. Plasmodium species of 5,141 confirmed cases were consistent with the initial diagnosis, with a species accuracy rate of 90.53% (5,141/5,679). The accuracy of P. falciparum diagnosis in health facilities was higher than that of non-falciparum species. The inconsistency between microscopy and nested polymerase chain reaction (nPCR) results of confirmatory diagnosis was mainly in malaria-positive versus malaria-negative cases, as well as in mixed versus single infection cases. Conclusion: The provincial malaria diagnosis reference laboratories have played an important role in ensuring the accuracy and reliability of Plasmodium diagnosis in health facilities. However, the results of this study imply that capacity training for the identification of Plasmodium species in health facilities is warranted.


Asunto(s)
Malaria , Plasmodium , Humanos , Laboratorios , Reproducibilidad de los Resultados , China/epidemiología , Malaria/diagnóstico , Malaria/prevención & control
11.
Front Public Health ; 11: 1239274, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37711239

RESUMEN

Objectives: The widespread occurrence of anti-malarial drug resistance threatens the current efforts to control malaria in African regions. Molecular marker surveillance helps to track the emergence and spread of drug-resistant malaria cases. Methods: A total of 237 Plasmodium falciparum infections imported from central Africa to Zhejiang Province, China, between 2016 and 2021, were investigated. Genomic DNA was extracted from blood samples of each patient and nested PCRs was used to detect molecular markers in k13, Pfcrt, and Pfmdr1 genes. The spatial and temporal distributions of the molecular markers were analyzed. Results: A limited polymorphism of k13 was observed, including two nonsynonymous (D464E and K503E) and five synonymous mutations. Wild-type CVMNK of Pfcrt predominated (78.5%), whereas 19.5% of the samples harbored the mutant haplotype, CVIET. The point mutation Y184F and the single mutant haplotype NF of Pfmdr1 were the most frequently observed. The geographical distributions of the Pfcrt and Pfmdr1 haplotypes displayed distinct patterns, with the mutant haplotype of Pfcrt more common in Gabon (53.9%) and Congo (50.0%), and wild haplotypes of Pfmdr1 more frequently found in Cameroon, Angola, and Congo. The prevalence of wild-type CVMNK of Pfcrt increased from 68.5-74.6% in 2016-2017 to 81.8-87.5% in 2018-2021. The proportion of wild-type Pfmdr1 also increased from 27.1% in 2016 to 38.5% in 2019. Conclusion: The geographical and temporal distribution of k13, Pfcrt, and Pfmdr1 polymorphisms in P. falciparum parasites imported from central Africa between 2016 and 2021 are demonstrated. Our data provide updated evidence that can be used to adjust anti-malarial drug policies in central Africa and China.


Asunto(s)
Antimaláricos , Parásitos , Humanos , Animales , Plasmodium falciparum/genética , Antimaláricos/farmacología , Biomarcadores , África Central/epidemiología
12.
Eur J Med Chem ; 259: 115689, 2023 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-37542993

RESUMEN

In recent years, the overuse of antibiotics has resulted in the emergence of antibiotic resistance, which is a serious global health problem. Methicillin-resistant Staphylococcus aureus (MRSA) is a common and virulent bacterium in clinical practice. Numerous researchers have focused on developing new candidate drugs that are effective, less toxic, and can overcome MRSA resistance. Thiazole derivatives have been found to exhibit antibacterial activity against drug-sensitive and drug-resistant pathogens. By hybridizing thiazole with other antibacterial pharmacophores, it is possible to obtain more effective antibacterial candidate drugs. Thiazole derivatives have shown potential in developing new drugs that can overcome drug resistance, reduce toxicity, and improve pharmacokinetic characteristics. This article reviews the recent progress of thiazole compounds as potential antibacterial compounds and examines the structure-activity relationship (SAR) in various directions. It covers articles published from 2018 to 2023, providing a comprehensive platform to plan and develop new thiazole-based small MRSA growth inhibitors with minimal side effects.


Asunto(s)
Antibacterianos , Staphylococcus aureus Resistente a Meticilina , Antibacterianos/farmacología , Tiazoles/farmacología , Pruebas de Sensibilidad Microbiana , Relación Estructura-Actividad
13.
World J Clin Cases ; 11(23): 5430-5439, 2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37637679

RESUMEN

BACKGROUND: Intracranial hemorrhage after spinal surgery is a rare and devastating complication. AIM: To investigate the economic burden, clinical characteristics, risk factors, and mechanisms of intracranial hemorrhage after spinal surgery. METHODS: A retrospective cohort study was conducted from January 1, 2015, to December 31, 2022. Patients aged ≥ 18 years, who had undergone spinal surgery were included. Intracranial hemorrhage patients were selected after spinal surgery during hospitalization. Based on the type of spinal surgery, patients with intracranial hemorrhage were randomly matched in a 1:5 ratio with control patients without intracranial hemorrhage. The patients' pre-, intra-, and post-operative data and clinical manifestations were recorded. RESULTS: A total of 24472 patients underwent spinal surgery. Six patients (3 males and 3 females, average age 71.3 years) developed intracranial hemorrhage after posterior spinal fusion procedures, with an incidence of 0.025% (6/24472). The prevailing type of intracranial hemorrhage was cerebellar hemorrhage. Two patients had a poor clinical outcome. Based on the type of surgery, 30 control patients were randomly matched in 1:5 ratio. The intracranial hemorrhage group showed significant differences compared with the control group with regard to age (71.33 ± 7.45 years vs 58.39 ± 8.07 years, P = 0.001), previous history of cerebrovascular disease (50% vs 6.7%, P = 0.024), spinal dura mater injury (50% vs 3.3%, P = 0.010), hospital expenses (RMB 242119.1 ± 87610.0 vs RMB 96290.7 ± 32029.9, P = 0.009), and discharge activity daily living score (40.00 ± 25.88 vs 75.40 ± 18.29, P = 0.019). CONCLUSION: The incidence of intracranial hemorrhage after spinal surgery was extremely low, with poor clinical outcomes. Patient age, previous stroke history, and dura mater damage were possible risk factors. It is suggested that spinal dura mater injury should be avoided during surgery in high-risk patients.

15.
Malar J ; 22(1): 209, 2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-37443070

RESUMEN

BACKGROUND: The global battle against malaria is facing formidable challenges, particularly in controlling Plasmodium vivax and Plasmodium ovale, whose cases have not been reduced as effectively as Plasmodium falciparum because of their relapse. This study investigates the current situation and underlying factors contributing to relapse or recrudescence of imported cases of P. vivax and P. ovale, and seeks to provide a reference for reducing relapse or recrudescence in malaria-free areas and offers a scientific basis for designing strategies to prevent imported re-transmission. METHODS: This study analysed imported P. vivax and P. ovale in Anhui, Zhejiang, Henan, Hubei, and Guangxi provinces during 2014-2021 by retrospective analysis. A case-control study was conducted on patients who experienced relapse or recrudescence. RESULTS: From 2014 to 2021, 306 cases of P.vivax and 896 cases of P.ovale were included in the study, while 75 cases had relapse or recrudescence, including 49 cases of P. ovale (65.33%) and 26 cases of P. vivax (34.67%). Within less than 5 weeks after returning to the country, 122 cases of P. vivax (39.87%, 122/306) and 265 cases of P. ovale (29.58%, 265/896) occurred. Within less than 53 weeks, the ratio of P. vivax was 94.77% (290/306), and that of P. ovale was 89.96% (806/896). Among the cases experiencing relapse or recrudescence, only 1 case of P. vivax (1/26 3.85%) and 3 cases of P. ovale (3/49 6.12%) occurred within less than 5 weeks after the first onset, whereas 21 cases of P. vivax (21/26 80.77%) and 42 cases of P. ovale (42/49 85.71%) occurred within less than 53 weeks after the first onset. The difference in relapse or recrudescence due to different drugs and medication regimens and medical activities at various levels of medical institutions was statistically significant. CONCLUSION: In areas where malaria has been eliminated, routine health screening in a scientific time frame for people returning from at-risk areas can effectively improve the efficiency of preventing re-transmission, thereby reducing prevention costs and disease burden. Preventing patients from self-treating and strengthening medication regulations in health facilities are key measures to reduce relapse or recrudescence.


Asunto(s)
Malaria Vivax , Malaria , Plasmodium ovale , Humanos , Plasmodium vivax , Estudios de Casos y Controles , Estudios Retrospectivos , China/epidemiología , Malaria/prevención & control , Malaria Vivax/epidemiología , Malaria Vivax/tratamiento farmacológico , Recurrencia , Enfermedad Crónica
16.
Front Public Health ; 11: 1203095, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37448654

RESUMEN

Background: This study aimed at exploring the epidemiological pattern of imported malaria in China before malaria elimination in 2021, to provide evidence-based data for preventing malaria re-establishment in China. Methods: Nine-year surveillance data on imported malaria in four provincial-level administrative divisions (PLADs) (Anhui, Chongqing, Guangxi, and Zhejiang) between 2011 and 2019 were thoroughly collected and analyzed. Results: A quite stable trend in imported malaria cases between 2011 and 2019 was observed. In total, 6,064 imported patients were included. Plasmodium falciparum was the most frequently reported species (4,575, 75.6%). Cases of malaria were most frequently imported from Western Africa (54.4%). We identified an increasing trend in P. ovale and a persistence of P. vivax infections among the cases of malaria imported from Western Africa. Most patients (97.5%) were 20-50 years old. Among imported malaria infections, the main purposes for traveling abroad were labor export (4,914/6,064, 81.0%) and business trips (649, 10.7%). Most patients (2,008/6,064, 33.1%) first visited county-level medical institutions when they sought medical help in China. More patients were diagnosed within 3 days after visiting Centers for Disease Control and Prevention (CDCs) or entry-exit quarantine facilities (EQFs) (1,147/1609, 71.3%) than after visiting medical institutions (2,182/3993, 54.6%). Conclusion: Imported malaria still poses a threat to the malaria-free status of China. County-level institutions are the primary targets in China to improve the sensitivity of the surveillance system and prevent the re-establishment of malaria. Health education should focus on exported labors, especially to Western and Central Africa. Increasing trend in P. ovale and persistence of P. vivax infections indicated their underestimations in Western Africa. Efficient diagnostic tools and sensitive monitoring systems are required to identify Plasmodium species in Africa.


Asunto(s)
Malaria , Plasmodium ovale , Humanos , Adulto Joven , Adulto , Persona de Mediana Edad , Plasmodium vivax , Incidencia , China/epidemiología , Malaria/epidemiología , Malaria/prevención & control
17.
JCI Insight ; 8(11)2023 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-37288658

RESUMEN

Previous studies implicate extracellular adenosine signaling in attenuating myocardial ischemia and reperfusion injury (IRI). This extracellular adenosine signaling is terminated by its uptake into cells by equilibrative nucleoside transporters (ENTs). Thus, we hypothesized that targeting ENTs would function to increase cardiac adenosine signaling and concomitant cardioprotection against IRI. Mice were exposed to myocardial ischemia and reperfusion injury. Myocardial injury was attenuated in mice treated with the nonspecific ENT inhibitor dipyridamole. A comparison of mice with global Ent1 or Ent2 deletion showed cardioprotection only in Ent1-/- mice. Moreover, studies with tissue-specific Ent deletion revealed that mice with myocyte-specific Ent1 deletion (Ent1loxP/loxP Myosin Cre+ mice) experienced smaller infarct sizes. Measurements of cardiac adenosine levels demonstrated that postischemic elevations of adenosine persisted during reperfusion after targeting ENTs. Finally, studies in mice with global or myeloid-specific deletion of the Adora2b adenosine receptor (Adora2bloxP/loxP LysM Cre+ mice) implied that Adora2b signaling on myeloid-inflammatory cells in cardioprotection provided by ENT inhibition. These studies reveal a previously unrecognized role for myocyte-specific ENT1 in cardioprotection by enhancing myeloid-dependent Adora2b signaling during reperfusion. Extension of these findings implicates adenosine transporter inhibitors in cardioprotection against ischemia and reperfusion injury.


Asunto(s)
Tranportador Equilibrativo 1 de Nucleósido , Isquemia Miocárdica , Receptor de Adenosina A2B , Daño por Reperfusión , Animales , Ratones , Adenosina , Tranportador Equilibrativo 1 de Nucleósido/genética , Miocardio , Receptor de Adenosina A2B/genética
18.
Nat Rev Cardiol ; 20(11): 723-737, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37308571

RESUMEN

Mammals have evolved to adapt to differences in oxygen availability. Although systemic oxygen homeostasis relies on respiratory and circulatory responses, cellular adaptation to hypoxia involves the transcription factor hypoxia-inducible factor (HIF). Given that many cardiovascular diseases involve some degree of systemic or local tissue hypoxia, oxygen therapy has been used liberally over many decades for the treatment of cardiovascular disorders. However, preclinical research has revealed the detrimental effects of excessive use of oxygen therapy, including the generation of toxic oxygen radicals or attenuation of endogenous protection by HIFs. In addition, investigators in clinical trials conducted in the past decade have questioned the excessive use of oxygen therapy and have identified specific cardiovascular diseases in which a more conservative approach to oxygen therapy could be beneficial compared with a more liberal approach. In this Review, we provide numerous perspectives on systemic and molecular oxygen homeostasis and the pathophysiological consequences of excessive oxygen use. In addition, we provide an overview of findings from clinical studies on oxygen therapy for myocardial ischaemia, cardiac arrest, heart failure and cardiac surgery. These clinical studies have prompted a shift from liberal oxygen supplementation to a more conservative and vigilant approach to oxygen therapy. Furthermore, we discuss the alternative therapeutic strategies that target oxygen-sensing pathways, including various preconditioning approaches and pharmacological HIF activators, that can be used regardless of the level of oxygen therapy that a patient is already receiving.


Asunto(s)
Enfermedades Cardiovasculares , Animales , Humanos , Enfermedades Cardiovasculares/tratamiento farmacológico , Hipoxia/terapia , Oxígeno/uso terapéutico , Oxígeno/metabolismo , Terapia por Inhalación de Oxígeno , Regulación de la Expresión Génica , Mamíferos/metabolismo
19.
Front Cardiovasc Med ; 10: 1188518, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37273884

RESUMEN

Background: Parasternal intercostal nerve block has been increasingly used for postoperative analgesia and has shown that this technique can provide effective postoperative analgesia. This study aimed to investigate the effect of preemptive parasternal intercostal nerve block on the opioid and vasoactive drug dose required for intraoperative hemodynamic stability and postoperative analgesia in patients undergoing off-pump coronary artery bypass grafting. Methods: In this prospective, randomized controlled study, 64 participants aged 45-75 years scheduled for off-pump coronary artery bypass grafting at The Second Xiangya Hospital of Central South University. Patients were randomized into two groups and preoperatively administered ropivacaine (group R) and saline (group S), in the parasternal intercostal spaces with ultrasound-guided bilateral nerve block. Results: The primary outcome was intraoperative sufentanil and vasopressor dosage. The secondary outcomes were intraoperative hemodynamics, postoperative pain scores, and anesthesia recovery, postoperative use of rescue dezocine, stay in intensive care unit, and length of hospital stay. The consumption of intraoperative sufentanil and vasopressor was significantly lower in group R than in group S. The visual analog score in group R was significantly lower than that in group S up to 12 h postoperatively. The time to anesthesia recovery was significantly less in group R than in group S. Most patients in group S required rescue dezocine, whereas most patients in group R did not. The hemodynamic variables were stable in all patients. Conclusions: A preemptive parasternal intercostal nerve block effectively reduced the required intraoperative sufentanil and norepinephrine dose and provided adequate analgesia for the first 12 h after surgery. Therefore, a preemptive parasternal intercostal nerve block is a good option for patients undergoing off-pump coronary artery bypass grafting. Clinical trial registration: chictr.org.cn, identifier ChiCTR1800017210.

20.
Front Immunol ; 14: 1163585, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37187740

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is characterized by a dense desmoplastic stroma that impedes drug delivery, reduces parenchymal blood flow, and suppresses the anti-tumor immune response. The extracellular matrix and abundance of stromal cells result in severe hypoxia within the tumor microenvironment (TME), and emerging publications evaluating PDAC tumorigenesis have shown the adenosine signaling pathway promotes an immunosuppressive TME and contributes to the overall low survival rate. Hypoxia increases many elements of the adenosine signaling pathway, resulting in higher adenosine levels in the TME, further contributing to immune suppression. Extracellular adenosine signals through 4 adenosine receptors (Adora1, Adora2a, Adora2b, Adora3). Of the 4 receptors, Adora2b has the lowest affinity for adenosine and thus, has important consequences when stimulated by adenosine binding in the hypoxic TME. We and others have shown that Adora2b is present in normal pancreas tissue, and in injured or diseased pancreatic tissue, Adora2b levels are significantly elevated. The Adora2b receptor is present on many immune cells, including macrophages, dendritic cells, natural killer cells, natural killer T cells, γδ T cells, B cells, T cells, CD4+ T cells, and CD8+ T cells. In these immune cell types, adenosine signaling through Adora2b can reduce the adaptive anti-tumor response, augmenting immune suppression, or may contribute to transformation and changes in fibrosis, perineural invasion, or the vasculature by binding the Adora2b receptor on neoplastic epithelial cells, cancer-associated fibroblasts, blood vessels, lymphatic vessels, and nerves. In this review, we discuss the mechanistic consequences of Adora2b activation on cell types in the tumor microenvironment. As the cell-autonomous role of adenosine signaling through Adora2b has not been comprehensively studied in pancreatic cancer cells, we will also discuss published data from other malignancies to infer emerging therapeutic considerations for targeting the Adora2b adenosine receptor to reduce the proliferative, invasive, and metastatic potential of PDAC cells.


Asunto(s)
Linfocitos T CD8-positivos , Neoplasias Pancreáticas , Receptor de Adenosina A2B , Humanos , Adenosina/metabolismo , Linfocitos T CD8-positivos/metabolismo , Hipoxia , Inmunoterapia , Neoplasias Pancreáticas/terapia , Microambiente Tumoral , Receptor de Adenosina A2B/efectos de los fármacos , Receptor de Adenosina A2B/metabolismo
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