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1.
BMC Cancer ; 24(1): 372, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38528507

RESUMEN

BACKGROUND: Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) recommended for the patients with subsolid nodule in early lung cancer stage is not routinely. The clinical value and impact in patients with EGFR mutation on survival outcomes is further needed to be elucidated to decide whether the application of EGFR-TKIs was appropriate in early lung adenocarcinoma (LUAD) stage appearing as subsolid nodules. MATERIALS AND METHODS: The inclusion of patients exhibiting clinical staging of IA-IIB subsolid nodules. Clinical information, computed tomography (CT) features before surgical resection and pathological characteristics including tertiary lymphoid structures of the tumors were recorded for further exploration of correlation with EGFR mutation and prognosis. RESULTS: Finally, 325 patients were enrolled into this study, with an average age of 56.8 ± 9.8 years. There are 173 patients (53.2%) harboring EGFR mutation. Logistic regression model analysis showed that female (OR = 1.944, p = 0.015), mix ground glass nodule (OR = 2.071, p = 0.003, bubble-like lucency (OR = 1.991, p = 0.003) were significant risk factors of EGFR mutations. Additionally, EGFR mutations were negatively correlated with TLS presence and density. Prognosis analysis showed that the presence of TLS was associated with better recurrence-free survival (RFS)(p = 0.03) while EGFR mutations were associated with worse RFS(p = 0.01). The RFS in patients with TLS was considerably excel those without TLS within EGFR wild type group(p = 0.018). Multivariate analyses confirmed that EGFR mutation was an independent prognostic predictor for RFS (HR = 3.205, p = 0.037). CONCLUSIONS: In early-phase LUADs, subsolid nodules with EGFR mutation had specific clinical and radiological signatures. EGFR mutation was associated with worse survival outcomes and negatively correlated with TLS, which might weaken the positive impact of TLS on prognosis. Highly attention should be paid to the use of EGFR-TKI for further treatment as agents in early LUAD patients who carrying EGFR mutation.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Estructuras Linfoides Terciarias , Humanos , Femenino , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Adenocarcinoma del Pulmón/diagnóstico por imagen , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/genética , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Pronóstico , Mutación , Receptores ErbB/genética , Receptores ErbB/uso terapéutico
2.
Acta Biochim Biophys Sin (Shanghai) ; 56(2): 291-303, 2024 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-37885429

RESUMEN

Cryptococcus gattii (Cg) is a facultative intracellular pathogen that can replicate and disseminate in mammalian macrophages, causing life-threatening cryptococcosis in both immunocompetent and immunocompromised individuals. Cryptococcus-macrophage interactions are crucial for cryptococcosis prognosis. However, the relationship between Cg pathogenicity and phagocytosis by macrophages has not yet been investigated in depth. In this study, a series of in vitro and in vivo experiments were conducted to investigate the interaction between macrophages and Cg. Flow cytometry was used to detect the phagocytic phenotypes of the Cg strains within macrophages. Scanning electron microscopy, transmission electron microscopy, and immunofluorescence were used to observe phagocytosis and proliferation, respectively. Survival and lung fungal burden tests were also performed. Our results show that Cg cells display different phagocytosis phenotypes, which are independent of the molecular type. Within macrophages, the high phagocytosis phenotype (HP) strains obtain higher intracellular proliferation than the low phagocytosis phenotype (LP) strains. At the early stage of infection in vivo, HP-inducing permissive granulomas within the lungs seldom limit the dissemination of cryptococci. In addition, HP strains could inhibit the formation of M1-type macrophages, proliferate intracellularly and disseminate extracellularly, and cause hypoxia induced by mucus and acidic polysaccharide accumulation in pulmonary alveoli much earlier than LP strains in vivo. Our work reveals that Cg displays diverse interactions with macrophages, which may enhance our understanding of the pathogenicity of this life-threatening pathogen.


Asunto(s)
Criptococosis , Cryptococcus gattii , Cryptococcus neoformans , Humanos , Animales , Cryptococcus gattii/genética , Virulencia , Macrófagos/microbiología , Fagocitosis , Criptococosis/microbiología , Fenotipo , Mamíferos
3.
Microbiol Spectr ; 11(6): e0244323, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37905820

RESUMEN

IMPORTANCE: Our study indicates that the molecular typing of Cryptococcus gattii is unrelated to virulence. The integration of animal experiments and clinical prognosis demonstrated that pathogenicity did not exhibit a direct correlation with in vitro virulence phenotypes or molecular genotypes, emphasizing the intricate nature of virulence. In conclusion, our research holds the potential to provide valuable insights into understanding the microbiological attributes of C. gattii in China.


Asunto(s)
Criptococosis , Cryptococcus gattii , Cryptococcus neoformans , Animales , Cryptococcus gattii/genética , Cryptococcus neoformans/genética , Virulencia , Tipificación Molecular , Genotipo , China , Criptococosis/microbiología
4.
J Phys Chem A ; 127(20): 4483-4491, 2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37170550

RESUMEN

Heteronuclear magnesium-iron carbonyl cation complexes MgFe(CO)n+ (n = 4-9) are prepared in the gas phase and are detected by mass-selected infrared photodissociation spectroscopy in the carbonyl stretching frequency region. The geometric structures and the metal-metal bonding are discussed with the aid of quantum chemical calculations. The MgFe(CO)9+ cation is a coordinatively saturated complex. Each complex is characterized to contain more than one isomer. The small complexes (n = 4-6) possess the Mg-Fe bonded [(OC)n-4Mg-Fe(CO)4]+ and/or [(OC)n-5Mg-Fe(CO)5]+ structures with all the carbonyl ligands terminally bonded. For the larger complexes with n = 7-9, the [(OC)n-4Mg-Fe(CO)4]+ structure is the major isomer experimentally observed. In addition, the [(OC)n-5Mg-OC-Fe(CO)4]+ isomer involving a linear bridging carbonyl ligand is also characterized. Bonding analyses indicate that each [(OC)n-4Mg-Fe(CO)4]+ complex contains a Mg-Fe electron-sharing σ bond. The metal-metal bond is described as a Mg(+I)-Fe(0) bond in MgFe(CO)4+ and as a Mg(+II)-Fe(-I) bond in the larger n = 5-9 complexes.

5.
J Am Chem Soc ; 145(16): 8817-8821, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37070757

RESUMEN

The importance of quantum-mechanical tunneling becomes increasingly recognized in chemical reactions involving hydrogen as well as heavier atoms. Here we report concerted heavy-atom tunneling in an oxygen-oxygen bond breaking reaction from cyclic beryllium peroxide to linear dioxide in cryogenic Ne matrix, as evidenced by subtle temperature-dependent reaction kinetics and unusually large kinetic isotope effects. Furthermore, we demonstrate that the tunneling rate can be tuned through noble gas atom coordination on the electrophilic beryllium center of Be(O2), as the half-life dramatically increased from 0.1 h for NeBe(O2) at 3 K to 12.8 h for ArBe(O2). Quantum chemistry and instanton theory calculations reveal that noble gas coordination notably stabilizes the reactants and transition states, increases the barrier heights and widths, and consequently reduces the reaction rate drastically. The calculated rates and in particular kinetic isotope effects are in good agreement with experiment.

6.
Acta Biochim Biophys Sin (Shanghai) ; 55(4): 540-547, 2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36815374

RESUMEN

Few therapeutic drugs and increased drug resistance have aggravated the current treatment difficulties of Cryptococcus in recent years. To better understand the antifungal drug resistance mechanism and treatment strategy of cryptococcosis. In this review, by combining the fundamental features of Cryptococcus reproduction leading to changes in its genome, we review recent research into the mechanism of four current anti-cryptococcal agents, coupled with new therapeutic strategies and the application of advanced technologies WGS and CRISPR-Cas9 in this field, hoping to provide a broad idea for the future clinical therapy of cryptococcosis.


Asunto(s)
Criptococosis , Cryptococcus , Humanos , Cryptococcus/genética , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Criptococosis/tratamiento farmacológico , Criptococosis/microbiología , Farmacorresistencia Fúngica/genética
7.
J Comput Chem ; 44(3): 129-137, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-35130353

RESUMEN

The reactions of coinage metal atoms Cu, Ag and Au with carbon suboxide (C3 O2 ) are studied by matrix isolation infrared spectroscopy. The weakly bound complexes TM-η1 -C3 O2 (TM=Cu, Ag, Au), in which the carbon suboxide ligand binds to the metal center in the monohapto fashion are formed as initial reaction products. The complexes subsequently isomerize to the inserted products OCTMCCO upon visible light (λ = 400-500 nm) excitation. The analysis of the electronic structure using modern quantum chemistry methods suggests that the linear OCTMCCO complexes are best described by the bonding interactions between the TM+ cation in the electronic singlet ground state and the [OC…CCO]- ligands in the doublet state forming two TM+ ← ligands σ donation and two TM+ → ligands π backdonation bonding components. In addition, the CuCCO, AgCCO and AuCCO complexes are also formed, which are predicted to be bent.

8.
Front Cell Infect Microbiol ; 12: 1041036, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36310879

RESUMEN

Cryptococcus is an invasive fungus that seriously endangers human life and health, with a complex and well-established immune-escaping mechanism that interferes with the function of the host immune system. Cryptococcus can attenuate the host's correct recognition of the fungal antigen and escape the immune response mediated by host phagocytes, innate lymphoid cells, T lymphocytes, B lymphocytes with antibodies, and peripheral cytokines. In addition, the capsule, melanin, dormancy, Titan cells, biofilm, and other related structures of Cryptococcus are also involved in the process of escaping the host's immunity, as well as enhancing the ability of Cryptococcus to infect the host.


Asunto(s)
Criptococosis , Cryptococcus gattii , Cryptococcus neoformans , Humanos , Criptococosis/microbiología , Inmunidad Innata , Linfocitos , Citocinas
9.
Nat Commun ; 13(1): 4622, 2022 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-35941135

RESUMEN

Clinical recommendations for Acute Myeloid Leukemia (AML) classification and risk-stratification remain heavily reliant on cytogenetic findings at diagnosis, which are present in <50% of patients. Using comprehensive molecular profiling data from 3,653 patients we characterize and validate 16 molecular classes describing 100% of AML patients. Each class represents diverse biological AML subgroups, and is associated with distinct clinical presentation, likelihood of response to induction chemotherapy, risk of relapse and death over time. Secondary AML-2, emerges as the second largest class (24%), associates with high-risk disease, poor prognosis irrespective of flow Minimal Residual Disease (MRD) negativity, and derives significant benefit from transplantation. Guided by class membership we derive a 3-tier risk-stratification score that re-stratifies 26% of patients as compared to standard of care. This results in a unified framework for disease classification and risk-stratification in AML that relies on information from cytogenetics and 32 genes. Last, we develop an open-access patient-tailored clinical decision support tool.


Asunto(s)
Leucemia Mieloide Aguda , Humanos , Análisis Citogenético , Citometría de Flujo/métodos , Quimioterapia de Inducción/métodos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Neoplasia Residual
10.
J Chem Phys ; 157(1): 014302, 2022 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-35803818

RESUMEN

A series of coinage metal complexes in the form of TMC(CO)n - (TM = Cu, Ag, Au; n = 0-3) were generated using a laser-ablation supersonic expansion ion source in the gas phase. Mass-selected infrared photodissociation spectroscopy in conjunction with quantum chemical calculations indicated that the TMC(CO)3 - complexes contain a linear OCTMCCO- core anion. Bonding analyses suggest that the linear OCTMCCO- anions are better described as the bonding interactions between a singlet ground state TM+ metal cation and the OC/CCO2- ligands in the singlet ground state. In addition to the strong ligands to metal σ donation bonding components, the π-bonding components also contribute significantly to the metal-ligand bonds due to the synergetic effects of the CO and CCO2- ligands. The strengths of the bonding of the three metals show a V-shaped trend in which the second-row transition metal Ag exhibits the weakest interactions whereas the third-row transition metal Au shows the strongest interactions due to relativistic effects.

11.
Phys Chem Chem Phys ; 24(21): 13149-13155, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35587654

RESUMEN

Beryllium-carbon dioxide cation complexes Be(CO2)n+ are produced by a laser vaporization-supersonic expansion ion source in the gas phase. Mass-selected infrared photodissociation spectroscopy supplemented by theoretical calculations confirms that Be(CO2)4+ is a coordination saturated complex that can be assigned to a mixture of two isomers. The first structure involves a bent CO2- ligand that is bound in a monodentate η1-O coordination mode. Another isomer has a metal oxalate-type C2O4- moiety with a C-C hemibond.

12.
J Am Chem Soc ; 144(18): 8355-8361, 2022 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-35482295

RESUMEN

The CaCO2 complex is generated via the reaction of excited-state calcium atom with carbon dioxide in a solid neon matrix. Infrared absorption spectroscopy and quantum chemical calculations reveal that the complex has a planar four-membered ring structure with a strongly bent CO2 ligand side-on coordinated to the calcium center in an η2-O, O manner. The complex has an open-shell singlet ground state, which can be described as the bonding interactions between a Ca+ (4s1) cation in the doublet ground state and a doublet ground state CO2- anion. The analysis of the bonding situation suggests that the Ca-O2C bonds have a large (75%) electrostatic character. The covalent (orbital) interactions come from the coupling of the unpaired electrons of Ca+ and CO2- giving rise to electron-sharing bonding and a stronger contribution from dative bonding (Ca+)←(CO2-). The atomic orbitals (AOs) of Ca+ that are engaged in the covalent bonds are the 4s AO for the electron-sharing bonds and the 3d AOs for the dative bonds. This is further evidence for the assignment of the heavier alkaline-earth atoms as transition metals rather than main-group elements.

13.
Clin Cancer Res ; 28(8): 1614-1627, 2022 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-35078859

RESUMEN

PURPOSE: Therapy-related myelodysplastic syndrome and acute leukemias (t-MDS/AL) are a major cause of nonrelapse mortality among pediatric cancer survivors. Although the presence of clonal hematopoiesis (CH) in adult patients at cancer diagnosis has been implicated in t-MDS/AL, there is limited published literature describing t-MDS/AL development in children. EXPERIMENTAL DESIGN: We performed molecular characterization of 199 serial bone marrow samples from 52 patients treated for high-risk neuroblastoma, including 17 with t-MDS/AL (transformation), 14 with transient cytogenetic abnormalities (transient), and 21 without t-MDS/AL or cytogenetic alterations (neuroblastoma-treated control). We also evaluated for CH in a cohort of 657 pediatric patients with solid tumor. RESULTS: We detected at least one disease-defining alteration in all cases at t-MDS/AL diagnosis, most commonly TP53 mutations and KMT2A rearrangements, including involving two novel partner genes (PRDM10 and DDX6). Backtracking studies identified at least one t-MDS/AL-associated mutation in 13 of 17 patients at a median of 15 months before t-MDS/AL diagnosis (range, 1.3-32.4). In comparison, acquired mutations were infrequent in the transient and control groups (4/14 and 1/21, respectively). The relative risk for development of t-MDS/AL in the presence of an oncogenic mutation was 8.8 for transformation patients compared with transient. Unlike CH in adult oncology patients, TP53 mutations were only detectable after initiation of cancer therapy. Last, only 1% of pediatric patients with solid tumor evaluated had CH involving myeloid genes. CONCLUSIONS: These findings demonstrate the clinical relevance of identifying molecular abnormalities in predicting development of t-MDS/AL and should guide the formation of intervention protocols to prevent this complication in high-risk pediatric patients.


Asunto(s)
Supervivientes de Cáncer , Leucemia Mieloide Aguda , Neuroblastoma , Adulto , Médula Ósea/patología , Niño , Células Clonales , Humanos , Leucemia Mieloide Aguda/genética , Neuroblastoma/patología
14.
JACS Au ; 1(10): 1631-1638, 2021 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-34723266

RESUMEN

The structure of the [Rh2C3]+ ion and its reaction with CH4 in the gas phase have been studied by infrared photodissociation spectroscopy and mass spectrometry in conjunction with quantum chemical calculations. The [Rh2C3]+ ion is characterized to have an unsymmetrical linear [Rh-C-C-C-Rh]+ structure existing in two nearly isoenergetic spin states. The [Rh2C3]+ ion reacts with CH4 at room temperature to form [Rh2C]+ + C3H4 and [Rh2C2H2]+ + C2H2 as the major products. In addition to the [Rh2C]+ ion, the [Rh2 13C]+ ion is formed at about one-half of the [Rh2C]+ intensity when the isotopic-labeled 13CH4 sample is used. The production of [Rh2 13C]+ indicates that the linear C3 moiety of [Rh2C3]+ can be replaced by the bare carbon atom of methane with all four C-H bonds being activated. The calculations suggest that the overall reactions are thermodynamically exothermic, and that the two Rh centers are the reactive sites for C-H bond activation and hydrogen atom transfer reactions.

15.
Eur J Pharmacol ; 912: 174620, 2021 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-34752743

RESUMEN

BACKGROUND: Epilepsy is a common chronic neurological disease. Recurrent seizures can cause irreversible brain damage. This study aimed to explore the regulation of Genistein on JAK2/STAT3 and Keap1/Nrf2 signaling pathway and the protective effects on brain injury after epilepsy. METHODS: Pentylenetetrazole (PTZ) was used to induce epilepsy in developing rats and Genistein was used for pretreatment of epilepsy. The seizure latency, grade scores and duration of the first generalized tonic-clonic seizure (GTCs) were recorded. Hippocampus tissue was sampled at 24 h post-epilepsy. Immunofluorescence staining was used to observe mature neurons, activated microglia and astrocytes in the hippocampal CA1 region. Western blot and qRT-PCR were used to determine the protein and mRNA levels of JAK2, STAT3, TNF-α, IL-1ß, Keap1, Nrf2, HO-1, NQO1, caspase3, Bax and Bcl2 in the hippocampus. RESULTS: Immunofluorescence showed that the number of neurons significantly decreased, and activated microglia and astrocytes significantly increased after epilepsy; Western blot and q-PCR showed that the expressions of JAK2, STAT3, TNF-α, IL-1ß, Keap1, caspase3 and Bax significantly increased, while Nrf2, HO-1, NQO1 and Bcl-2 were significantly reduced after epilepsy. These effects were reversed by Genistein treatment. Moreover, Genistein was found to prolong seizure latency and reduce seizure intensity score and duration of generalized tonic-clonic seizures(GTCs) CONCLUSIONS: Genistein can activate the Keap1/Nrf2 antioxidant stress pathway and attenuate the activation of microglia and astrocytes. Genistein also inhibits the JAK2-STAT3 inflammation pathway and expression of apoptotic proteins, and increases the number of surviving neurons, thus having a protective effect on epilepsy-induced brain damage.


Asunto(s)
Lesiones Encefálicas/prevención & control , Genisteína/farmacología , Janus Quinasa 2/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Fármacos Neuroprotectores/farmacología , Factor de Transcripción STAT3/metabolismo , Animales , Apoptosis/efectos de los fármacos , Astrocitos/efectos de los fármacos , Lesiones Encefálicas/etiología , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/patología , Caspasa 3/genética , Caspasa 3/metabolismo , Modelos Animales de Enfermedad , Epilepsia/complicaciones , Epilepsia/metabolismo , Epilepsia/patología , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Janus Quinasa 2/antagonistas & inhibidores , Proteína 1 Asociada A ECH Tipo Kelch/antagonistas & inhibidores , Proteína 1 Asociada A ECH Tipo Kelch/genética , Masculino , Microglía/efectos de los fármacos , Factor 2 Relacionado con NF-E2/antagonistas & inhibidores , Factor 2 Relacionado con NF-E2/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas Sprague-Dawley , Factor de Transcripción STAT3/antagonistas & inhibidores , Factor de Transcripción STAT3/genética , Transducción de Señal/efectos de los fármacos , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismo
17.
Angew Chem Int Ed Engl ; 60(25): 13865-13870, 2021 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-33826215

RESUMEN

Heteronuclear calcium-iron carbonyl cation complexes in the form of [CaFe(CO)n ]+ (n=5-12) are produced in the gas phase. Infrared photodissociation spectroscopy in conjunction with quantum chemical calculations confirm that the n=10 complex is the coordination saturated ion where a Fe(CO)4 fragment is bonded with a Ca(CO)6 fragment through two side-on bridging carbonyl ligands. Bonding analysis indicates that it is best described by the bonding interactions between a [Ca(CO)6 ]2+ dication and an [Fe(CO)4 ]- anion forming a Fe→Ca d-d dative bond in the [(CO)6 Ca-Fe(CO)4 ]+ structure, which enriches the pool of experimentally observed complexes of calcium that mimic transition metal compounds. The molecule is the first example of a heteronuclear carbonyl complex featuring a d-d bond between calcium and a transition metal.

19.
Nat Commun ; 12(1): 338, 2021 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-33436578

RESUMEN

Stably acquired mutations in hematopoietic cells represent substrates of selection that may lead to clonal hematopoiesis (CH), a common state in cancer patients that is associated with a heightened risk of leukemia development. Owing to technical and sample size limitations, most CH studies have characterized gene mutations or mosaic chromosomal alterations (mCAs) individually. Here we leverage peripheral blood sequencing data from 32,442 cancer patients to jointly characterize gene mutations (n = 14,789) and mCAs (n = 383) in CH. Recurrent composite genotypes resembling known genetic interactions in leukemia genomes underlie 23% of all detected autosomal alterations, indicating that these selection mechanisms are operative early in clonal evolution. CH with composite genotypes defines a patient group at high risk of leukemia progression (3-year cumulative incidence 14.6%, CI: 7-22%). Multivariable analysis identifies mCA as an independent risk factor for leukemia development (HR = 14, 95% CI: 6-33, P < 0.001). Our results suggest that mCA should be considered in conjunction with gene mutations in the surveillance of patients at risk of hematologic neoplasms.


Asunto(s)
Aberraciones Cromosómicas , Evolución Clonal/genética , Hematopoyesis Clonal/genética , Mutación/genética , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Neoplasias Hematológicas/genética , Humanos , Persona de Mediana Edad , Mosaicismo , Neoplasias/genética , Medición de Riesgo , Selección Genética , Adulto Joven
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