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1.
PLoS Pathog ; 20(6): e1012246, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38857264

RESUMEN

Antibody-mediated immunity plays a key role in protection against SARS-CoV-2. We characterized B-cell-derived anti-SARS-CoV-2 RBD antibody repertoires from vaccinated and infected individuals and elucidate the mechanism of action of broadly neutralizing antibodies and dissect antibodies at the epitope level. The breadth and clonality of anti-RBD B cell response varies among individuals. The majority of neutralizing antibody clones lose or exhibit reduced activities against Beta, Delta, and Omicron variants. Nevertheless, a portion of anti-RBD antibody clones that develops after a primary series or booster dose of COVID-19 vaccination exhibit broad neutralization against emerging Omicron BA.2, BA.4, BA.5, BQ.1.1, XBB.1.5 and XBB.1.16 variants. These broadly neutralizing antibodies share genetic features including a conserved usage of the IGHV3-53 and 3-9 genes and recognize three clustered epitopes of the RBD, including epitopes that partially overlap the classically defined set identified early in the pandemic. The Fab-RBD crystal and Fab-Spike complex structures corroborate the epitope grouping of antibodies and reveal the detailed binding mode of broadly neutralizing antibodies. Structure-guided mutagenesis improves binding and neutralization potency of antibody with Omicron variants via a single amino-substitution. Together, these results provide an immunological basis for partial protection against severe COVID-19 by the ancestral strain-based vaccine and indicate guidance for next generation monoclonal antibody development and vaccine design.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Humanos , SARS-CoV-2/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/inmunología , COVID-19/prevención & control , Vacunas contra la COVID-19/inmunología , Anticuerpos Neutralizantes/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Inmunización Secundaria , Epítopos/inmunología , Linfocitos B/inmunología
2.
Proc Natl Acad Sci U S A ; 118(5)2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33452205

RESUMEN

The outbreak of COVID-19 caused by SARS-CoV-2 has resulted in more than 50 million confirmed cases and over 1 million deaths worldwide as of November 2020. Currently, there are no effective antivirals approved by the Food and Drug Administration to contain this pandemic except the antiviral agent remdesivir. In addition, the trimeric spike protein on the viral surface is highly glycosylated and almost 200,000 variants with mutations at more than 1,000 positions in its 1,273 amino acid sequence were reported, posing a major challenge in the development of antibodies and vaccines. It is therefore urgently needed to have alternative and timely treatments for the disease. In this study, we used a cell-based infection assay to screen more than 3,000 agents used in humans and animals, including 2,855 small molecules and 190 traditional herbal medicines, and identified 15 active small molecules in concentrations ranging from 0.1 nM to 50 µM. Two enzymatic assays, along with molecular modeling, were then developed to confirm those targeting the virus 3CL protease and the RNA-dependent RNA polymerase. Several water extracts of herbal medicines were active in the cell-based assay and could be further developed as plant-derived anti-SARS-CoV-2 agents. Some of the active compounds identified in the screen were further tested in vivo, and it was found that mefloquine, nelfinavir, and extracts of Ganoderma lucidum (RF3), Perilla frutescens, and Mentha haplocalyx were effective in a challenge study using hamsters as disease model.


Asunto(s)
Antivirales/farmacología , Tratamiento Farmacológico de COVID-19 , SARS-CoV-2/efectos de los fármacos , Adulto , Animales , Antivirales/química , Antivirales/uso terapéutico , COVID-19/epidemiología , COVID-19/virología , Chlorocebus aethiops , Cricetinae , Modelos Animales de Enfermedad , Reposicionamiento de Medicamentos/métodos , Femenino , Humanos , Masculino , Pandemias , Extractos Vegetales/farmacología , SARS-CoV-2/genética , Células Vero
3.
Anal Chem ; 95(47): 17153-17161, 2023 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-37966312

RESUMEN

Solid-state nanopores have wide applications in DNA sequencing, energy conversion and storage, seawater desalination, sensors, and reactors due to their high stability, controllable geometry, and a variety of pore-forming materials. Solid-state nanopore sensors can be used for qualitative and quantitative analyses of ions, small molecules, proteins, and nucleic acids. The combination of nucleic acid amplification and solid-state nanopores to achieve trace detection of analytes is gradually attracting attention. This review outlines nucleic acid amplification strategies for enhancing the sensitivity of solid-state nanopore sensors by summarizing the articles published in the past 10 years. The future development prospects and challenges of nucleic acid amplification in solid-state nanopore sensors are discussed. This review helps readers better understand the field of solid-state nanopore sensors. We believe that solid-state nanopore sensors will break through the bottleneck of traditional detection and become a powerful single-molecule detection platform.


Asunto(s)
Nanoporos , Ácidos Nucleicos , Ácidos Nucleicos/análisis , Nanotecnología , Proteínas , Técnicas de Amplificación de Ácido Nucleico
4.
Small ; 19(17): e2207111, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36599616

RESUMEN

Chirality transfer is of vital importance that dominates the structure and functionality of biological systems and living matters. External physical stimulations, e.g. polarized light and mechanical forces, can trigger the chirality symmetry breaking, leading to the appearance of the enantiomeric entities created from a chiral self-assembly of achiral molecule. Here, several 2D assemblies with different chirality, synthesized on Au(111) surface by using achiral building blocks - glycylglycine (digly), the simplest polypeptide are reported. By delicately tuning the kinetic factors, i.e., one-step slow/rapid deposition, or stepwise slow deposition with mild annealing, achiral square hydrogen-bond organic frameworks (HOF), homochiral rhombic HOF and racemic rectangular assembly are achieved, respectively. Chirality induction and related symmetry broken in assemblies are introduced by the handedness (H-bond configurations in principle) of the assembled motifs and then amplified to the entire assemblies via the interaction between motifs. The results show that the chirality transfer and induction of biological assemblies can be tuned by altering the kinetic factors instead of applying external forces, which may offer an in-depth understanding and practical approach to peptide chiral assembly on the surfaces and can further facilitate the design of desired complex biomolecular superstructures.

5.
Clin Sci (Lond) ; 137(5): 367-383, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36857175

RESUMEN

BACKGROUND: Acute respiratory distress syndrome (ARDS) is a respiratory condition caused by severe endothelial barrier dysfunction within the lung. In ARDS, excessive inflammation, tissue edema, and immune cell influx prevents endothelial cell regeneration that is crucial in repairing the endothelial barrier. However, little is known about the molecular mechanism that underpin endothelial cell regeneration in ARDS. METHODS: R-based bioinformatics tools were used to analyze microarray-derived transcription profiles in human lung microvascular endothelial cells (HLMVECs) subjected to non-treatment or lipopolysaccharide (LPS) exposure. We generated endothelial cell-specific interferon regulatory factor 1 (Irf1) knockout (Irf1EC-/-) and Irf1fl/fl control mice for use in an endotoxemic murine model of acute lung injury (ALI). In vitro studies (qPCR, immunoblotting, and ChIP-qPCR) were conducted in mouse lung endothelial cells (MLECs) and HLMVECs. Dual-luciferase promoter reporter assays were performed in HLMVECs. RESULTS: Bioinformatics analyses identified IRF1 as a key up-regulated gene in HLMVECs post-LPS exposure. Endothelial-specific knockout of Irf1 in ALI mice resulted in enhanced regeneration of lung endothelium, while liposomal delivery of endothelial-specific Irf1 to wild-type ALI mice inhibited lung endothelial regeneration in a leukemia inhibitory factor (Lif)-dependent manner. Mechanistically, we demonstrated that LPS-induced Stat1Ser727 phosphorylation promotes Irf1 transactivation, resulting in downstream up-regulation of Lif that inhibits endothelial cell proliferation. CONCLUSIONS: These results demonstrate the existence of a p-Stat1Ser727-Irf1-Lif axis that inhibits lung endothelial cell regeneration post-LPS injury. Thus, direct inhibition of IRF1 or LIF may be a promising strategy for enhancing endothelial cell regeneration and improving clinical outcomes in ARDS patients.


Asunto(s)
Lesión Pulmonar Aguda , Factor 1 Regulador del Interferón , Síndrome de Dificultad Respiratoria , Animales , Humanos , Ratones , Lesión Pulmonar Aguda/inducido químicamente , Células Endoteliales , Endotelio , Inflamación/tratamiento farmacológico , Factor 1 Regulador del Interferón/genética , Lipopolisacáridos/farmacología , Pulmón , Ratones Endogámicos C57BL , Regeneración , Ratones Noqueados
6.
Environ Sci Technol ; 57(20): 7789-7799, 2023 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-37159565

RESUMEN

The groundwater quality impacts associated with anthropogenic groundwater recharge (AGR) are of great concern for water management. However, the impacts of AGR on the molecular properties of dissolved organic matter (DOM) in aquifers are poorly understood. Herein, Fourier transform ion cyclotron resonance mass spectrometry was used to unravel the molecular characteristics of DOM in groundwaters from recharge areas by reclaimed water (RWRA) and natural water from South-to-North Water Diversion Project (SNWRA). Compared with RWRA groundwater, significantly fewer nitrogenous compounds, more sulfur-containing compounds, higher concentrations of NO3-N, and lower pH were observed in SNWRA groundwater, indicating the occurrence of deamination, sulfurization, and nitrification. The occurrence of these processes was further supported by transformations of more molecules related to nitrogen and sulfur in SNWRA groundwater relative to RWRA groundwater. The intensities of most common molecules in all samples were significantly correlated with the water quality indicators (e.g., Cl- and NO3-N) and fluorescent indicators (e.g., humic-like components (C1%)), indicating that those common molecules may have the potential to track the environmental impact of AGR on groundwater, especially these specific molecules having great mobility and being significantly correlated with other inert tracers like C1% and Cl-. This study is helpful to understand the environmental risks and regional applicability of AGR.


Asunto(s)
Materia Orgánica Disuelta , Agua Subterránea , Agua Subterránea/química , Calidad del Agua , Compuestos de Azufre
7.
Aging Clin Exp Res ; 35(11): 2603-2611, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37656411

RESUMEN

BACKGROUND: Systemic inflammatory response syndrome (SIRS) greatly affects postoperative lives of afflicted aged patients. This study aimed to determine whether preoperative high hs-CRP/HDL ratio (CHR) was associated with an increased risk of postoperative SIRS in the elderly population. METHODS: This retrospective cohort study included data on patients aged ≥ 65 years who underwent general anesthesia surgery at two clinical centers between January 2015 and September 2020. The primary exposure was preoperative CHR which was divided into two groups (≤ 12.82 and > 12.82) based on its normal range in our hospital, and the primary outcome was the incidence of postoperative SIRS. Targeted maximum likelihood estimation analyses were used to model the exposure-outcome relationship. RESULTS: The analysis included 5595 elderly patients, of whom 1410 (25.20%) developed SIRS within three postoperative days. Targeted maximum likelihood estimation analysis revealed that elderly patients with CHR > 12.82 vs. CHR ≤ 12.82 was associated with increased risk of postoperative SIRS (aOR = 1.40, 95% CI [1.33, 1.48], P < 0.001). Those results were consistent both in subgroup analyses and sensitivity analyses. Compared with patients with CHR ≤ 12.82, patients with CHR > 12.82 had a higher prevalence of postoperative SIRS (49.06% vs. 22.70%), postoperative in-hospital mortality (3.40% vs. 0.65%), a longer hospital stay after surgery [10 (IQR, 6-16) vs. 8 (IQR, 5-11) days] and higher direct medical cost [10070 (IQR, 6878-15577) vs. 7117 (IQR, 4079-10314) euros, all P < 0.001]. CONCLUSIONS: In elderly patients, preoperative CHR > 12.82 was significantly associated with a higher risk of postoperative SIRS.


Asunto(s)
Proteína C-Reactiva , Síndrome de Respuesta Inflamatoria Sistémica , Humanos , Anciano , Síndrome de Respuesta Inflamatoria Sistémica/epidemiología , Síndrome de Respuesta Inflamatoria Sistémica/etiología , Proteína C-Reactiva/análisis , Estudios Retrospectivos , Complicaciones Posoperatorias/etiología , Incidencia
8.
Ann Hum Biol ; 50(1): 126-135, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36943097

RESUMEN

CONTEXT: Evidence about the effect of age at menarche (AAM) on blood pressure (BP) has largely been drawn from studies in developed countries. Studies in developing countries are expanding recently but have not been summarised. OBJECTIVE: To systematically explore the association between AAM and BP and the potential modifiers in developing countries. METHODS: We searched PubMed, Embase, and Web of Science for publications until March 2022. A random-effects model was used to calculate the pooled relative risk (RR) with 95% confidence interval (CI). RESULTS: Twenty studies were eligible. In studies with participants' mean age at BP assessment <55 years, women in the oldest group as compared with the middle or the youngest group of AAM had a higher risk of hypertension in those studies without adjustment for confounders (RR 1.79, 95% CI 1.41-2.28, I2=97.0%), those with adjustment for confounders excluding adiposity (1.25,1.04-1.51, I2=84.8%), and those with adjustment for confounders including adiposity (1.38,1.03-1.86, I2=91.8%). In studies with participants' mean age at BP assessment ≥55 years, no significant differences were found for studies without adjustment for confounders (RR 1.07, 95% CI 0.78-1.47, I2=90.3%), studies with adjustment for confounders excluding adiposity (0.85, 0.78-0.92, I2=12.3%), or studies with adjustment for confounders including adiposity (0.95, 0.80-1.11, I2=45.5%). A similar association was observed between AAM and baseline systolic BP and diabolic BP. CONCLUSION: Late menarche was associated with a higher risk of BP and this association was modified by age and adiposity in developing countries.


Asunto(s)
Hipertensión , Menarquia , Adulto , Humanos , Femenino , Persona de Mediana Edad , Menarquia/fisiología , Presión Sanguínea , Factores de Riesgo , Países en Desarrollo , Hipertensión/epidemiología , Hipertensión/etiología , Obesidad
9.
J Environ Sci (China) ; 123: 476-486, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36522007

RESUMEN

Over the past decade, fine particulate matter (PM) pollution in China has been abated significantly, benefiting from strict emission control measures, but particulate nitrate continues to rise. Here, we review the progress in particulate nitrate (pNO3-) pollution characterization, nitrate formation mechanisms, and the proposed control strategies in China. The spatial and temporal distributions of pNO3- are summarized. The current status of knowledge on the chemical mechanism is updated, and the significance of its formation pathways is assessed by various approaches such as field observation and modelling of nitrate production rate, as well as isotopic analysis. The factors impacting pNO3- formation and the corresponding pollution regulation strategies are discussed, in which the importance of atmospheric oxidation capacity and ammonia are addressed. Finally, the challenges and open questions in pNO3- pollution control in China are outlined.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Nitratos/análisis , Monitoreo del Ambiente , Material Particulado/análisis , Polvo/análisis , China , Contaminación del Aire/prevención & control , Contaminación del Aire/análisis , Estaciones del Año
10.
Trop Med Int Health ; 27(10): 864-872, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35942809

RESUMEN

OBJECTIVES: To estimate the coverage and willingness of pneumococcal vaccination and further explore the influencing factors of vaccination willingness among people in mainland China. METHODS: Literature searches were conducted independently by two researchers in English- and Chinese-language databases from database inception to 6 October 2021. A random-effects meta-analysis model was used to derive summary vaccination coverage and willingness. Predefined subgroup analysis and meta-regression were performed to explore the sources of heterogeneity. RESULTS: A total of 97 studies were included in this meta-analysis. The summary vaccination coverage in 76 included studies was 21.7% (95% confidence interval [CI]: 17.2%-26.5%). Subgroup analysis shows that the summary coverage was 29.0% (95% CI, 20.4%-39.1%) among the permanent residents and 20.7% (95% CI, 12.4%-35.9%) among the floating residents. The eastern and central regions presented higher coverage than the western region. Notable differences were observed between the various study populations. A total of 27 studies provided an estimation of vaccination willingness, with a summary willingness of 51.2% (95% CI, 40.4%-61.9%). In subgroup analysis, the summary willingness was 57.9% (95% CI, 48.3%-67.2%) in urban areas and 52.3% (95% CI, 40.8%-63.8%) in rural areas. Parents with children and people with a history of pneumonia were more willing to be vaccinated than the elderly. Recommendations by family members and physicians, previous pneumococcal and influenza vaccination, perceived vaccination effectiveness and severity of disease and a history of pneumonia contributed to vaccination willingness. CONCLUSIONS: Compared to global estimates and other countries, pneumococcal vaccination coverage and willingness are at a lower level in mainland China. Recommendations for vaccination by family members and doctors, a history of vaccination and the perception of pneumonia and vaccination are associated with greater willingness to be vaccinated.


Asunto(s)
Neumonía , Cobertura de Vacunación , Anciano , Niño , China , Humanos , Streptococcus pneumoniae , Vacunación
11.
Brain ; 144(11): 3421-3435, 2021 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-34918046

RESUMEN

Huntington's disease is an autosomal-dominant neurodegenerative disease caused by CAG expansion in exon 1 of the huntingtin (HTT) gene. Since mutant huntingtin (mHTT) protein is the root cause of Huntington's disease, oligonucleotide-based therapeutic approaches using small interfering RNAs (siRNAs) and antisense oligonucleotides designed to specifically silence mHTT may be novel therapeutic strategies for Huntington's disease. Unfortunately, the lack of an effective in vivo delivery system remains a major obstacle to realizing the full potential of oligonucleotide therapeutics, especially regarding the delivery of oligonucleotides to the cortex and striatum, the most severely affected brain regions in Huntington's disease. In this study, we present a synthetic biology strategy that integrates the naturally existing exosome-circulating system with artificial genetic circuits for self-assembly and delivery of mHTT-silencing siRNA to the cortex and striatum. We designed a cytomegalovirus promoter-directed genetic circuit encoding both a neuron-targeting rabies virus glycoprotein tag and an mHTT siRNA. After being taken up by mouse livers after intravenous injection, this circuit was able to reprogramme hepatocytes to transcribe and self-assemble mHTT siRNA into rabies virus glycoprotein-tagged exosomes. The mHTT siRNA was further delivered through the exosome-circulating system and guided by a rabies virus glycoprotein tag to the cortex and striatum. Consequently, in three mouse models of Huntington's disease treated with this circuit, the levels of mHTT protein and toxic aggregates were successfully reduced in the cortex and striatum, therefore ameliorating behavioural deficits and striatal and cortical neuropathologies. Overall, our findings establish a convenient, effective and safe strategy for self-assembly of siRNAs in vivo that may provide a significant therapeutic benefit for Huntington's disease.


Asunto(s)
Ingeniería Genética/métodos , Terapia Genética/métodos , Proteína Huntingtina , Enfermedad de Huntington , ARN Interferente Pequeño , Animales , Exosomas/metabolismo , Hígado/metabolismo , Ratones , ARN Interferente Pequeño/farmacología , Transfección
12.
Biochem Biophys Res Commun ; 572: 1-6, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34332323

RESUMEN

In the past, specificity and affinity were the priority for synthetic antibody library. However, therapeutic antibodies need good stability for medical use. Through carefully adjust the chemical diversity in CDRs, one hopes to design a synthetic antibody library with good developability. Here we thoroughly analyzed 296 nanobody sequences and structures, constructed a fully-functional synthetic nanobody library, evaluated the relationship between aggregation and isoelectric point, and found that high-pI nanobodies were more resistant to aggregation than low-pIs. As we used the same framework for constructing the library, CDRs charge played a crucial role in mediating nanobody aggregation. We also analyzed the theoretical pI of 296 nanobodies from PDB, about 75% had basic pI, only 25% were acidic. Those results provided useful guidelines for designing next-generation synthetic nanobody libraries and for identifying potent and safe nanobody therapeutics.


Asunto(s)
Regiones Determinantes de Complementariedad/química , Anticuerpos de Dominio Único/química , Humanos , Biblioteca de Péptidos , Agregado de Proteínas
13.
J Cell Biochem ; 121(8-9): 3871-3881, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31693229

RESUMEN

Colorectal cancer (CRC) is a type of malignant cancer that has become particularly prevalent worldwide. It is of crucial importance to CRC treatment that the underlying molecular mechanism of CRC progression is determined. The NRAS gene is an important small G protein that is involved in various biological processes, including cancers. NRAS is an oncogene in many neoplasms but its function and regulation in CRC have seldom been investigated. In this study, it was uncovered that the NRAS protein was significantly upregulated in CRC tissues. According to a bioinformatics prediction, we identified that miR-144 may target NRAS to suppress its expression. In vitro experiments indicated that miR-144 decreased NRAS expression in different CRC cell lines (SW480, LoVo, and Caco2). By inhibiting NRAS, miR-144 repress SW480 cell proliferation and migration. Moreover, miR-144 decelerated the growth of SW480 xenograft tumors in vivo by targeting NRAS. In summary, our results identified a novel miR-144-NRAS axis in CRC that could promote the research and treatment of CRC.

14.
Environ Sci Technol ; 54(15): 9243-9253, 2020 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-32589840

RESUMEN

Particulate nitrate (pNO3-) has often been found to be the major component of fine particles in urban air-sheds in China, the United States, and Europe during winter haze episodes in recent years. However, there is a lack of knowledge regarding the experimentally determined contribution of different chemical pathways to the formation of pNO3-. Here, for the first time, we combine ground and tall-tower observations to quantify the chemical formation of pNO3- using observationally constrained model approach based on direct observations of OH and N2O5 for the urban air-shed. We find that the gas-phase oxidation pathway (OH+NO2) during the daytime is the dominant channel over the nocturnal uptake of N2O5 during pollution episodes, with percentages of 74% in urban areas and 76% in suburban areas. This is quite different from previous studies in some regions of the US, in which the uptake of N2O5 was concluded to account for a larger contribution in winter. These results indicate that the driving factor of nitrate pollution in Beijing and different regions of the US is different, as are the mitigation strategies for particulate nitrate.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Contaminantes Atmosféricos/análisis , Beijing , China , Monitoreo del Ambiente , Europa (Continente) , Material Particulado/análisis , Estaciones del Año
15.
Clin Invest Med ; 43(2): E35-46, 2020 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-32593275

RESUMEN

PURPOSE: Crush and Culotte techniques have been used increasingly to treat patients with complex unprotected left main coronary artery bifurcation lesions. This article compares published data on these two techniques. METHODS: Databases, including PubMed, Embase, Cochrane Library, Wanfang Data and China National Knowledge Infrastructure, were searched for articles published before Aug 21, 2019 to identify all relevant studies on left main coronary artery bifurcation lesions treated by Crush versus Culotte techniques. The pooled data were analyzed using either fixed- or random-effects model depending on heterogeneity (assessed via the I2 index). The endpoints were major adverse cardiac events, target lesion revascularization, cardiac death, stent thrombosis, myocardial infarction and target vessel revascularization. RESULTS: Eight articles with a total of 1,283 patients were included, and 710 patients were treated with Crush, and 573 ones with Culotte. Crush group was trend to decreased major adverse cardiac event compared with Culotte group [Relative ratio (RR) 0.63,95% confidence interval(CI) 0.39-1.04, I2 =72.7%], mainly driven by decreased cardiac death [RR 0.49, 95% CI(0.25-0.99), I2 =0%], decreased myocardial infarction [RR 0.40, 95% CI(0.21-0.76), I2 =21.6%],and lower stent thrombosis [RR 0.39, 95% CI(0.16-0.98), I2 =39.4%]. There was no significant difference in target lesion revascularization and target vessel revascularization between Crush and Culotte [RR 0.77, 95% CI 0.46-1.28, I2=61.1%; RR 0.78, 95% CI (0.30-2.02), I2 =73.1%, respectively]. CONCLUSION: Crush was superior to Culotte for treatment of left main coronary artery bifurcation lesions with a trend of lower incidence of long-term major adverse cardiac events, mainly derived from decreased myocardial infarction, stent thrombosis and cardiac death.


Asunto(s)
Enfermedad de la Arteria Coronaria , Intervención Coronaria Percutánea , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/cirugía , Humanos , Stents , Factores de Tiempo , Resultado del Tratamiento
16.
Biochemistry ; 58(46): 4610-4620, 2019 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-31638374

RESUMEN

Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, requires iron for survival. In Mtb, MhuD is the cytosolic protein that degrades imported heme. MhuD is distinct, in both sequence and structure, from canonical heme oxygenases (HOs) but homologous with IsdG-type proteins. Canonical HO is found mainly in eukaryotes, while IsdG-type proteins are predominantly found in prokaryotes, including pathogens. While there are several published structures of MhuD and other IsdG-type proteins in complex with the heme substrate, no structures of IsdG-type proteins in complex with a product have been reported, unlike the case for HOs. We recently showed that the Mtb variant MhuD-R26S produces biliverdin IXα (αBV) rather than the wild-type mycobilin isomers. Given that mycobilin and other IsdG-type protein products like staphylobilin are difficult to isolate in quantities sufficient for structure determination, here we use the MhuD-R26S variant and its product αBV as a proxy to study the IsdG-type protein-product complex. First, we show that αBV has a nanomolar affinity for MhuD and the R26S variant. Second, we determined the MhuD-R26S-αBV complex structure to 2.5 Å, which reveals two notable features: (1) two αBV molecules bound per active site and (2) a novel α-helix (α3) that was not observed in previous MhuD-heme structures. Finally, through molecular dynamics simulations, we show that α3 is stable with the proximal αBV alone. MhuD's high affinity for the product and the observed structural and electrostatic changes that accompany substrate turnover suggest that there may be an unidentified class of proteins that are responsible for the extraction of products from MhuD and other IsdG-type proteins.


Asunto(s)
Proteínas Bacterianas/química , Biliverdina/metabolismo , Hemo/metabolismo , Oxigenasas de Función Mixta/química , Mycobacterium tuberculosis/metabolismo , Proteínas Bacterianas/metabolismo , Biliverdina/química , Cristalografía por Rayos X , Hemo/química , Humanos , Oxigenasas de Función Mixta/metabolismo , Modelos Moleculares , Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/genética , Mutación Puntual , Conformación Proteica , Especificidad por Sustrato , Tuberculosis/microbiología
17.
J Cell Biochem ; 120(5): 7527-7538, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30417502

RESUMEN

Gastric cancer (GC) is a worldwide health problem. Uncovering the underlining molecular mechanisms of GC is of vital significance. Here, we identified a novel oncogene WW domain-containing E3 ubiquitin protein ligase 1 (WWP1) in GC. WWP1 could promote GC cell proliferation and migration in vitro and expedite GC growth in vivo. We also found out two microRNAs (miRNAs): miR-129-5p and -3p could both target WWP1. Interestingly, miR-129-5p bound to the CDS region of WWP1 mRNA. The miR-129 pairs (miR-129-5p and -3p) play pivotal roles in GC to suppress its proliferation and migration in vitro and slow down GC growth in vivo by repressing WWP1. In summary, we identified two tumor suppressive miRNAs which share the same precursor that could regulate the same oncogene WWP1 in GC. Our finding would add new route for GC research and treatment.

18.
Clin Gastroenterol Hepatol ; 17(7): 1303-1310.e18, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-29654915

RESUMEN

BACKGROUND & AIMS: The Chinese herbal medicine, MaZiRenWan (MZRW), has been used for more than 2000 years to treat constipation, but it has not been tested in a randomized controlled trial. We performed a trial to evaluate the efficacy and safety of MZRW, compared with the stimulant laxative senna or placebo, for patients with functional constipation (FC). METHODS: We performed a double-blind, double-dummy, trial of 291 patients with FC based on Rome III criteria, seen at 8 clinics in Hong Kong from June 2013 through August 2015. Patients were observed for 2 weeks and then assigned randomly (1:1:1) to groups given MZRW (7.5 g, twice daily), senna (15 mg daily), or placebo for 8 weeks. Patients were then followed for 8 weeks and evaluated at baseline and weeks 4, 8 (end of treatment), and 16 (end of follow up). Participants recorded information on stool form and frequency, feeling of complete evacuation, and research medication taken. Data on individual bowel symptoms, global symptom improvement, and adverse events were collected. A complete response was defined as an increase ≥1 complete spontaneous bowel movement (CSBM)/week from baseline (the primary outcome). Secondary outcomes included response during the follow-up period, colonic transit, individual and global symptom assessments, quality of life measured with 36-item short form Chinese version, and adverse events. RESULTS: Although there was no statistically significant difference in proportions of patients with a complete response to MZRW (68%) vs. senna (57.7%) (P = .14) at week 8, there was a statistically significant difference vs. placebo (33.0%) (P < .005). At the 16-week timepoint (after the 8-week follow-up period), 47.4% of patients had a complete response to MZRW, 20.6% had a complete response to senna, and 17.5% had a complete response to placebo (P < .005 for MZRW vs. placebo). The group that received MZRW group also had significant increases in colonic transit and reduced severity of constipation, straining, incomplete evacuation, and global constipation symptoms compared with the groups that received placebo or senna in (P < .05 for all comparisons). CONCLUSIONS: In a randomized controlled trial of 291 patients with FC, we found MZRW to be well-tolerated and effective in increasing CSBM/week. MZRW did not appear to be more effective than senna and might be considered as an alternative to this drug. ClincialTrials.gov no: NCT01695850.


Asunto(s)
Estreñimiento/tratamiento farmacológico , Defecación/efectos de los fármacos , Medicamentos Herbarios Chinos/uso terapéutico , Calidad de Vida , Estreñimiento/fisiopatología , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
19.
Chemphyschem ; 20(3): 489-498, 2019 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-30548521

RESUMEN

Organometal halide perovskites have been outstanding from enormous amount of functional materials thanks to their highly cost-effective processability and prominent light harvesting capacity. Unfortunately, poor long-term stability seriously hinders their further development. The recent experimental observations suggest that Cesium is a promising candidate to enhance the stability of MAPbI3 . To explore the inherent mechanism, a first-principles investigation based on density functional theory, including hybrid functional, has been performed to analyze the electronic and optical properties of perovskite series MA0.75 Cs0.25 PbI3-y Bry . The results indicate that perovskite compound MA0.75 Cs0.25 PbI2 Br is significantly superior to the other doped series in terms of optical absorption within the visible-light range. In the meanwhile, both Bader charge analysis and charge density distribution show that the compound of MA0.75 Cs0.25 PbI2 Br is the most stable among all the doped perovskite series. Moreover, it is clearly manifested that the impact of cesium is mainly embodied in the enhancement of the stability rather than in the improvement of optical absorption. Our study sheds a new light on screening new-type light harvesting materials, and provides theoretical insight into the rationale design of highly efficient and stable photovoltaic devices based on these functional materials.

20.
Med Microbiol Immunol ; 208(2): 215-226, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30707297

RESUMEN

Streptococcuspneumoniae, or pneumococcus, is a major respiratory-tract pathogen that causes high levels of mortality and morbidity in infants and elderly individuals. Despite the development of various capsular polysaccharide vaccines to prevent pneumococcal disease, it remains epidemic. Pneumococcal surface protein A (PspA) is a highly immunogenic surface protein existing in all strains of S. pneumoniae, and it can elicit immunizing protection against pneumococcal infection. In our previous studies, a fusion protein (PsaA-PspA23), consisting of PspA and pneumococcal surface antigen A (PsaA), displayed greater immunogenicity and provided better protection in mice against S. pneumoniae strains than either PsaA or PspA. In this study, the fusion protein PsaA-PspA23, together with PspA4, was formulated with four adjuvants Al(OH)3, MF59, AS03, and AS02, and subsequently subjected to dose optimization and immunological evaluation for determination of the antibody titers, bacterial burden, survival rates, and levels of cytokines in mice. All vaccines with high adjuvant doses displayed higher antigen-specific immunoglobulin G (IgG) titers. Bacterial burdens were notably decreased to different extents in the lungs and blood of mice immunized with the antigen and various adjuvants. Among these adjuvants, AS02 provided outstanding protection against challenge with pathogenic bacteria from different families and clades; it also induced high titers of IgG1 and IgG2a. Moreover, only AS02 elicited high levels of cytokines, such as TNF-α, IFN-γ, IL-2, and IL-4. These results suggest that PsaA-PspA23 and PspA4 formulated with AS02 may potentially be used as a subunit vaccine against deadly pneumococcal infection.


Asunto(s)
Adhesinas Bacterianas/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Proteínas Bacterianas/inmunología , Lipoproteínas/inmunología , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas/inmunología , Adhesinas Bacterianas/genética , Animales , Anticuerpos Antibacterianos/sangre , Carga Bacteriana , Proteínas Bacterianas/genética , Citocinas/análisis , Modelos Animales de Enfermedad , Femenino , Lipoproteínas/genética , Ratones Endogámicos BALB C , Vacunas Neumococicas/administración & dosificación , Vacunas Neumococicas/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Análisis de Supervivencia , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunología
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