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1.
Microb Drug Resist ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39166283

RESUMEN

Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection has become a significant threat to global health. The application of chemical disinfectants is an effective infection control strategy to prevent the spread of CRKP in hospital environments. However, bacteria have shown reduced sensitivity to clinical disinfectants in recent years. Furthermore, bacteria can acquire antibiotic resistance due to the induction of disinfectants, posing a considerable challenge to hospital infection prevention and control. This study collected 68 CRKP strains from the Fifth Affiliated Hospital of Xinjiang Medical University in China from 2023 to 2024. These strains were isolated from the sputum, urine, and whole blood samples of patients diagnosed with CRKP infection. Antibiotic susceptibility tests were performed on CRKP strains. Concurrently, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of disinfectants (benzalkonium bromide, 1% iodophor disinfectant, alcohol, and chlorine-containing disinfectant) against the test isolates were determined by the broth microdilution method. The efflux pump genes (cepA, qacE, qacEΔ1, qacEΔ1-SUL1, oqxA, and oqxB) were detected using polymerase chain reaction. The results showed that 21 out of the 68 CRKP strains exhibited extensive drug resistance, whereas 47 were nonextensively drug-resistant. The MIC value for benzalkonium bromide disinfectants displayed statistically significant differences (p < 0.05) between extensively drug-resistant (XDR) and non-XDR strains. Additionally, the MBC values for benzalkonium bromide disinfectants and 1% iodophor disinfectants displayed statistically significant differences (p < 0.05) between XDR and non-XDR strains. The detection rates for the efflux pump genes were as follows: cepA 52.9%, qacE 39.7%, qacEΔ1 35.2%, qacEΔ1-SUL1 52.9%, oqxA 30.8%, and oqxB 32.3%. The detection rate of the qacEΔ1-SUL1 gene in XDR CRKP strains was significantly higher than in non-XDR CRKP strains (p < 0.05). This indicates a potential link between CRKP bacterial disinfectant efflux pump genes and CRKP bacterial resistance patterns. Ongoing monitoring of the declining sensitivity of XDR strains against disinfectants is essential for the effective control and prevention of superbug.

2.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(8): 840-844, 2024 Aug 15.
Artículo en Chino | MEDLINE | ID: mdl-39148389

RESUMEN

OBJECTIVES: To investigate the clinical phenotypes and genotypes of children with congenital fibrinogen disorder (CFD). METHODS: A retrospective analysis was conducted on the clinical data of 16 children with CFD. Polymerase chain reaction was used to amplify all exons and flanking sequences of the FGA, FGB, and FGG genes, and sequencing was performed to analyze mutation characteristics. RESULTS: Among the 16 children, there were 9 boys (56%) and 7 girls (44%), with a median age of 4 years at the time of attending the hospital. Among these children, 9 (56%) attended the hospital due to bleeding events, and 7 (44%) were diagnosed based on preoperative examination. The children with bleeding events had a significantly lower fibrinogen activity than those without bleeding events (P<0.05). Genetic testing was conducted on 12 children and revealed a total of 12 mutations, among which there were 4 novel mutations, i.e., c.80T>C and c.1368delC in the FGA gene and c.1007T>A and C.1053C>A in the FGG gene. There were 2 cases of congenital afibrinogenemia caused by null mutations of the FGA gene, with relatively severe bleeding symptoms. There were 7 cases of congenital dysfibrinogenemia mainly caused by heterozygous missense mutations of the FGG and FGA genes, and their clinical phenotypes ranged from asymptomatic phenotype to varying degrees of bleeding. CONCLUSIONS: The clinical phenotypes of children with CFD are heterogeneous, and the severity of bleeding is associated with the level of fibrinogen activity, but there is a weak association between clinical phenotype and genotype.


Asunto(s)
Afibrinogenemia , Fibrinógeno , Genotipo , Mutación , Fenotipo , Humanos , Masculino , Femenino , Afibrinogenemia/genética , Preescolar , Niño , Fibrinógeno/genética , Lactante , Estudios Retrospectivos , Adolescente , Hemorragia/genética , Hemorragia/etiología
3.
Microbiol Spectr ; : e0012224, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39150249

RESUMEN

Background emergence of multidrug-resistant (MDR) bacterial strains is a public health concern that threatens global and regional security. Efflux pump-overexpressing MDR strains from clinical isolates are the best subjects for studying the mechanisms of MDR caused by bacterial efflux pumps. A Klebsiella pneumoniae strain overexpressing the OqxB-only efflux pump was screened from a clinical strain library to explore reverse OqxB-mediated bacterial resistance strategies. We identified non-repetitive clinical isolated K. pneumoniae strains using a matrix-assisted laser desorption/ionization time-of-flight (TOF) mass spectrometry clinical TOF-II (Clin-TOF-II) and susceptibility test screening against levofloxacin and ciprofloxacin. And the polymorphism analysis was conducted using pulsed-field gel electrophoresis. Efflux pump function of resistant strains is obtained by combined drug sensitivity test of phenylalanine-arginine beta-naphthylamide (PaßN, an efflux pump inhibitor) and detection with ethidium bromide as an indicator. The quantitative reverse transcription PCR was performed to assess whether the oqxB gene was overexpressed in K. pneumoniae isolates. Additional analyses assessed whether the oqxB gene was overexpressed in K. pneumoniae isolates and gene knockout and complementation strains were constructed. The binding mode of PaßN with OqxB was determined using molecular docking modeling. Among the clinical quinolone-resistant K. pneumoniae strains, one mediates resistance almost exclusively through the overexpression of the resistance-nodulation-division efflux pump, OqxB. Crystal structure of OqxB has been reported recently by N. Bharatham, P. Bhowmik, M. Aoki, U. Okada et al. (Nat Commun 12:5400, 2021, https://doi.org/10.1038/s41467-021-25679-0). The discovery of this strain will contribute to a better understanding of the role of the OqxB transporter in K. pneumoniae and builds on the foundation for addressing the threat posed by quinolone resistance.IMPORTANCEThe emergence of antimicrobial resistance is a growing and significant health concern, particularly in the context of K. pneumoniae infections. The upregulation of efflux pump systems is a key factor that contributes to this resistance. Our results indicated that the K. pneumoniae strain GN 172867 exhibited a higher oqxB gene expression compared to the reference strain ATCC 43816. Deletion of oqxB led a decrease in the minimum inhibitory concentration of levofloxacin. Complementation with oqxB rescued antibiotic resistance in the oqxB mutant strain. We demonstrated that the overexpression of the OqxB efflux pump plays an important role in quinolone resistance. The discovery of strain GN 172867 will contribute to a better understanding of the role of the OqxB transporter in K. pneumoniae and promotes further study of antimicrobial resistance.

4.
Antimicrob Agents Chemother ; : e0034424, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39194261

RESUMEN

Limited treatment options and multidrug-resistant (MDR) Klebsiella pneumoniae present a significant therapeutic challenge, underscoring the need for novel approaches. Drug repurposing is a promising tool for augmenting the activity of many antibiotics. This study aimed to identify novel synergistic drug combinations against K. pneumoniae based on drug repurposing. We used the clinically isolated GN 172867 MDR strain of K. pneumoniae to determine the reversal resistance activity of zidovudine (AZT). The combined effects of AZT and various antibiotics, including nitrofurantoin (NIT) and omadacycline (OMC), were examined using the checkerboard method, growth curves, and crystal violet assays to assess biofilms. An in vitro combination activity testing was carried out in 12 isolates of K. pneumoniae. In vivo murine urinary tract and lung infection models were used to evaluate the therapeutic effects of AZT + NIT and AZT + OMC, respectively. The fractional inhibitory concentration index and growth curve demonstrated that AZT synergized with NIT or OMC against K. pneumoniae strains. In addition, AZT + NIT inhibited biofilm formation and cleared mature biofilms. In vivo, compared with untreated GN 172867-infected mice, AZT + NIT and AZT + OMC treatment decreased colony counts in multiple tissues (P < 0.05) and pathological scores in the bladder and kidneys (P < 0.05) and increased the survival rate by 60% (P < 0.05). This study evaluated the combination of AZT and antibiotics to treat drug-resistant K. pneumoniae infections and found novel drug combinations for the treatment of acute urinary tract infections. These findings suggest that AZT may exert significant anti-resistance activity.

5.
Environ Pollut ; 357: 124470, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38950848

RESUMEN

Seasonal variations in black carbon (BC) pollution characteristics during haze episodes in Benxi city, Liaoning province, were analyzed using year-long measurements of BC, carbon monoxide (CO), and PM2.5. Haze frequencies were recorded to be 0.07, 0.03 and 0.14 in spring, autumn, and winter respectively. Solid fuel contributions increased notably by 7%-8% during haze events compared to clean periods in all seasons. Transitioning from clean to haze periods led to ΔBC/ΔCO increases of 16% in spring and autumn, and 6.8% in winter, while BC/PM2.5 ratios decreased by approximately 33%, 50%, and 24% for spring, autumn, and winter respectively, likely indicating enhanced residential and industrial contributions. These further led to an increase in BC absorption capacities by factors of around 2.2 in spring and autumn, and up to 2.6 in winter during haze periods. Despite liquid fuel sources dominating BC emissions, certain haze episodes (frequency <10%) showed solid fuel contributions of up to 65%, highlighting BC pollution complexity in the region during haze. Backward trajectories analysis revealed local air masses from Liaoning province arrived consistently with the most occurrence of haze events across all seasons, while long-range air masses from Mongolian regions, though with less frequent occurrence during haze periods, significantly elevated BC loadings from solid fuel sources, particularly in spring and autumn due to biomass burning. Despite higher BC wet scavenging rates (WSR) in long-range air masses (0.072 ng m-3 ppbv-1 mm-1) compared to local air masses (0.039 ng m-3 ppbv-1 mm-1), significant BC transport persisted due to limited precipitation along transport pathways, especially during haze periods. These findings provide crucial insights for policymakers, highlighting the need for targeted haze prevention and control strategies focusing on mitigating BC emissions in Northeast China.


Asunto(s)
Contaminantes Atmosféricos , Monitoreo del Ambiente , Material Particulado , Estaciones del Año , Hollín , China , Contaminantes Atmosféricos/análisis , Hollín/análisis , Material Particulado/análisis , Monóxido de Carbono/análisis , Contaminación del Aire/estadística & datos numéricos , Atmósfera/química
6.
Sci Total Environ ; 948: 174829, 2024 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-39034012

RESUMEN

Dust storms have great impacts on air quality and climate. Dust can influence cloud microphysical properties and determine their radiative forcing and precipitation. Asian dust storms (ADS) are important sources of global aerosol. However, the physiochemical characteristics of dust from ADS at a single particle level are less understood, and the exact particles that can serve as ice nucleating particles (INPs) remain unclear. Here, we present the physicochemical properties and ice nucleation ability of dust particles collected in Beijing during two major ADS in March 2021. The particles from two ADS were classified into Illite, Kaolinite, Feldspar, Quartz, Chlorite, Mixed-dust, and Non-dust particles, which contributed 28.6 % ± 3.3 %, 20.0 % ± 3.9 %, 12.3 % ± 2.3 %, 11.1 % ± 2.8 %, 9.8 % ± 0.8 %, 13.7 % ± 1.8 %, and 4.4 % ± 1.7 % in number, respectively. On average, the ADS particles formed ice crystals via deposition ice nucleation from relative humidity with respect to ice (RHice) of 112 % ± 1 % at 250 K to 154 % ± 15 % RHice at 205 K. Part of the samples also formed ice via immersion freezing between 230 K and 250 K. Among the 149 identified INPs, Clay-like particles (Chlorite, Illite, and Kaolinite) contributed 71.1 % ± 6.2 % in number and followed by Mixed-dust-like particles (16.9 % ± 8.7 %) and Feldspar-like particles (10.4 % ± 6.3 %). Enrichment factor of each particle type in INPs is calculated as the ratio of its number fractions in INPs and the aerosol population. It ranges from 0.6 ± 0.7 to 1.3 ± 2.2. The contribution of each particle type to INP was correlated with its fraction in the population. These results imply that each particle type can serve as INP. Clay-like particles are the dominant INPs during the ADS. We conducted ice nucleation kinetic analysis and provided parameterizations of heterogeneous ice nucleation rate coefficient and contact angle for ADS. These parameterizations can be used in the modeling study to evaluate the impact of ADS in atmospheric ice crystal formation in clouds.

7.
Int J Mol Sci ; 25(14)2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39063077

RESUMEN

Rice straw is an agricultural waste, the disposal of which through open burning is an emerging challenge for ecology. Green manufacturing using straw returning provides a more avant-garde technique that is not only an effective management measure to improve soil fertility in agricultural ecosystems but also nurtures environmental stewardship by reducing waste and the carbon footprint. However, fresh straw that is returned to the field cannot be quickly decomposed, and screening microorganisms with the capacity to degrade straw and understanding their mechanism of action is an efficient approach to solve such problems. This study aimed to reveal the potential mechanism of influence exerted by exogenous degradative bacteria (ZJW-6) on the degradation of straw, growth of plants, and soil bacterial community during the process of returning rice straw to the soil. The inoculation with ZJW-6 enhanced the driving force of cellulose degradation. The acceleration of the rate of decomposition of straw releases nutrients that are easily absorbed by rice (Oryza sativa L.), providing favorable conditions for its growth and promoting its growth and development; prolongs the photosynthetic functioning period of leaves; and lays the material foundation for high yields of rice. ZJW-6 not only directly participates in cellulose degradation as degrading bacteria but also induces positive interactions between bacteria and fungi and enriches the microbial taxa that were related to straw degradation, enhancing the rate of rice straw degradation. Taken together, ZJW-6 has important biological potential and should be further studied, which will provide new insights and strategies for the appropriate treatment of rice straw. In the future, this degrading bacteria may provide a better opportunity to manage straw in an ecofriendly manner.


Asunto(s)
Bacterias , Oryza , Microbiología del Suelo , Oryza/microbiología , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Bacterias/metabolismo , Bacterias/crecimiento & desarrollo , Tallos de la Planta/microbiología , Tallos de la Planta/metabolismo , Celulosa/metabolismo , Biodegradación Ambiental , Agricultura/métodos , Suelo/química
8.
Org Lett ; 26(27): 5614-5619, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38953701

RESUMEN

Although various types of asymmetric cyclization reactions of 1,6-enynes have been established, simple asymmetric reductive cyclization remains underdeveloped. In this study, the enantioselective reductive cyclization of alkynyl-tethered cyclohexadienones (1,6-enynes) has been developed via a chiral pincer rhodium catalyst, affording cis-hydrobenzofurans and cis-hydroindoles with high enantioselectivities (90-99% ee). Furthermore, several synthetic applications and preliminary inhibitory activity studies against SARS-CoV-2 3CLpro are presented.

9.
Front Med (Lausanne) ; 11: 1407716, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38873202

RESUMEN

Gallbladder Torsion (GT) refers to serious biliary emergencies caused by the torsion of the gallbladder on its mesentery along the axis of the cystic duct and cystic artery. It is very rare, especially in children. The clinical data of a child with floating gallbladder torsion who was treated in our hospital on March 14, 2024, were analyzed. A 6-year-old girl presented with abdominal pain and vomiting. Physical examination showed a mass in the right middle abdomen. Laboratory tests showed normal liver biochemical function and white blood cells. The benign lesion was considered by color Doppler ultrasound and CT, and the floating torsion of the gallbladder was diagnosed by MRCP and laparoscopic exploration. The child was treated with laparoscopic cholecystectomy (LC) and recovered well after the operation.

10.
Cell Biochem Biophys ; 82(2): 1421-1431, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38750384

RESUMEN

Pemetrexed is a folate analog metabolic inhibitor that is given for therapy of non-small cell lung cancer (NSCLC). Drug resistance affects the efficacy of pemetrexed in NSCLC. Lentinan is a polysaccharide extracted from Shiitake mushrooms which has antitumor roles in multiple cancers, including lung cancer. However, the effects of lentinan on pemetrexed resistance in NSCLC remain unclear. In present study, The pemetrexed-resistant NSCLC cells were established and exposed to pemetrexed and lentinan. Oxidative stress was investigated via mitochondrial membrane potential (JC-1 staining), levels of MDA and SOD.The phosphorylation and total of PI3K and Akt levels were actuated using specific activator 740Y-P and measured through western blot. We observed that Lentinan decreased IC50 of pemetrexed in resistant NSCLC cells. Lentinan aggravated pemetrexed-induced proliferation inhibition of resistant NSCLC cells via reducing PCNA levels. Lentinan exacerbated pemetrexed-triggered oxidative stress through increasing ROS and MDA levels, and reducing mitochondrial membrane potential and SOD levels. Lentinan inhibited PI3K/Akt signaling activation in pemetrexed-treated cells. Activated PI3K/Akt pathway using activator 740Y-P reversed the effects of lentinan on pemetrexed-mediated proliferation inhibition and oxidative stress. Our findings uncover that Lentinan mitigates pemetrexed resistance in NSCLC through inhibiting cell proliferation and inducing oxidative stress by suppressing PI3K/Akt signaling.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Resistencia a Antineoplásicos , Lentinano , Neoplasias Pulmonares , Potencial de la Membrana Mitocondrial , Estrés Oxidativo , Pemetrexed , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Pemetrexed/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Lentinano/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Transducción de Señal/efectos de los fármacos , Línea Celular Tumoral , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Antineoplásicos/farmacología , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismo
11.
Phytochemistry ; 223: 114120, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38705265

RESUMEN

Eleven previously undescribed sesquiterpenoids (8-18), one undescribed jasmonic acid derivative (35) and 28 known compounds were isolated from the leaves of Artemisia stolonifera. Undescribed compounds with their absolute configurations were determined by extensive spectroscopic analysis, single-crystal X-ray diffraction and ECD calculation. Compound 8 was identified as a rare sesquiterpenoid featuring a rearranged 5/8 bicyclic ring system, whereas compound 17 was found to be an unprecedented monocyclic sesquiterpenoid with methyl rearrangement. Evaluation of biological activity showed that compounds 1-5 and 7 displayed cytotoxicity against six tumor cells. In the meantime, compounds 11, 12, 18 and 35 exhibited inhibitory effects against LPS-stimulated NO production in RAW 264.7 macrophage cells and reduced the transcription of IL-6 and IL-1ß in a dose-dependent manner at 25, 50 and 100 µM. Moreover, the anti-inflammatory-based network pharmacology and molecular docking analyses revealed potential target proteins of 11, 12, 18 and 35.


Asunto(s)
Antiinflamatorios , Artemisia , Ciclopentanos , Óxido Nítrico , Oxilipinas , Sesquiterpenos , Artemisia/química , Ratones , Oxilipinas/farmacología , Oxilipinas/química , Oxilipinas/aislamiento & purificación , Animales , Células RAW 264.7 , Sesquiterpenos/química , Sesquiterpenos/farmacología , Sesquiterpenos/aislamiento & purificación , Ciclopentanos/química , Ciclopentanos/farmacología , Ciclopentanos/aislamiento & purificación , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Estructura Molecular , Relación Estructura-Actividad , Simulación del Acoplamiento Molecular , Humanos , Relación Dosis-Respuesta a Droga , Lipopolisacáridos/farmacología , Lipopolisacáridos/antagonistas & inhibidores , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Hojas de la Planta/química , Ensayos de Selección de Medicamentos Antitumorales
12.
J Glob Health ; 14: 04058, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38602274

RESUMEN

Background: Due to a lack of related research, we aimed to determine the effectiveness of a pharmacist-led medication reconciliation intervention in China. Methods: We conducted a multicentre, prospective, open-label, assessor-blinded, cluster, nonrandomised controlled study at six county-level hospitals, with hospital wards serving as the clusters. We included patients discharged from the sampled hospitals who were aged ≥60 years; had ≥1 studied diagnoses; and were prescribed with ≥3 medications at discharge. Patients in the intervention group received a pharmacist-led medication reconciliation intervention and those in the control group received standard care. We assessed the incidence of medication discrepancies at discharge, patients' medication adherence, and health care utilisation within 30 days after discharge. Results: There were 429 patients in the intervention group (mean age = 72.5 years, standard deviation (SD) = 7.0) and 526 patients in the control group (mean age = 73.6 years, SD = 7.1). Of the 1632 medication discrepancies identified at discharge, fewer occurred in the intervention group (1.9 per patient on average) than the control group (2.6 per patient on average).The intervention significantly reduced the incidence of medication discrepancy by 9.6% (95% confidence interval (CI) = -15.6, -3.6, P = 0.002) and improved patients' medication adherence, with an absolute decrease in the mean adherence score of 2.5 (95% CI = -2.8, -2.2, P < 0.001). There was no significant difference in readmission rates between the intervention and control groups. Conclusions: Pharmacist-led medication reconciliation at discharge from Chinese county-level hospitals reduced medication discrepancies and improved patients' adherence among patients aged 60 years or above, though no impact on readmission after discharge was observed. Registration: ChiCTR2100045668.


Asunto(s)
Conciliación de Medicamentos , Farmacéuticos , Humanos , Anciano , Estudios Prospectivos , Hospitales de Condado , Cumplimiento de la Medicación
13.
Bioorg Chem ; 146: 107330, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38579615

RESUMEN

The increased de novo serine biosynthesis confers many advantages for tumorigenesis and metastasis. Phosphoglycerate dehydrogenase (PHGDH), a rate-limiting enzyme in serine biogenesis, exhibits hyperactivity across multiple tumors and emerges as a promising target for cancer treatment. Through screening our in-house compound library, we identified compound Stattic as a potent PHGDH inhibitor (IC50 = 1.98 ± 0.66 µM). Subsequent exploration in structural activity relationships led to the discovery of compound B12 that demonstrated the increased enzymatic inhibitory activity (IC50 = 0.29 ± 0.02 µM). Furthermore, B12 exhibited robust inhibitory effects on the proliferation of MDA-MB-468, NCI-H1975, HT1080 and PC9 cells that overexpress PHGDH. Additionally, using a [U-13C6]-glucose tracing assay, B12 was found to reduce the production of glucose-derived serine in MDA-MB-468 cells. Finally, mass spectrometry-based peptide profiling, mutagenesis experiment and molecular docking study collectively suggested that B12 formed a covalent bond with Cys421 of PHGDH.


Asunto(s)
Inhibidores Enzimáticos , Fosfoglicerato-Deshidrogenasa , Simulación del Acoplamiento Molecular , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Serina , Glucosa , Línea Celular Tumoral
14.
Angew Chem Int Ed Engl ; 63(25): e202405150, 2024 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-38591857

RESUMEN

In biological systems, nucleotide quadruplexes (such as G-quadruplexes) in DNA and RNA that are held together by multiple hydrogen bonds play a crucial functional role. The biomimetic formation of these hydrogen-bonded quadruplexes captured by artificial systems in water poses a significant challenge but can offer valuable insights into these complex functional structures. Herein, we report the formation of biomimetic hydrogen-bonded G ⋅ C ⋅ G ⋅ C quadruplex captured by a tetraphenylethene (TPE) based octacationic spirobicycle (1). The spirobicyclic compound possesses a three-dimensional (3D) crossing dual-cavity structure, which enables the encapsulation of four d(GpC) dinucleotide molecules, thereby realizing 1 : 4 host-guest complexation in water. The X-ray structure reveals that four d(GpC) molecules further form a two-layer G ⋅ C ⋅ G ⋅ C quadruplex with Watson-Crick hydrogen bonds, which are stabilized within the dual hydrophobic cavities of 1 through the cooperative non-covalent interactions of hydrogen bonds, CH⋅⋅⋅π interactions, and hydrophobic effect. Due to the dynamically-rotational propeller chirality of TPE units, 1 with adaptive chirality can further serve as a chiroptical sensor to exhibit opposite Cotton effects with mirror-image CD spectra for the pH-dependent hydrogen-bonded assemblies of d(GpC) including the Watson-Crick G ⋅ C ⋅ G ⋅ C (pH 9.22) and Hoogsteen G ⋅ C+ ⋅ G ⋅ C+ (pH 5.74) quartets through the host-guest chirality transfer in water.


Asunto(s)
G-Cuádruplex , Enlace de Hidrógeno , Agua , Agua/química , Estilbenos/química , Compuestos de Espiro/química , Modelos Moleculares , Estructura Molecular , Materiales Biomiméticos/química
15.
Microb Drug Resist ; 30(5): 179-191, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38621166

RESUMEN

This study evaluates whether random forest (RF) models are as effective as traditional Logistic Regression (LR) models in predicting multidrug-resistant Gram-negative bacterial nosocomial infections. Data were collected from 541 patients with hospital-acquired Gram-negative bacterial infections at two tertiary-level hospitals in Urumqi, Xinjiang, China, from August 2022 to November 2023. Relevant literature informed the selection of significant predictors based on patients' pre-infection clinical information and medication history. The data were split into a training set of 379 cases and a validation set of 162 cases, adhering to a 7:3 ratio. Both RF and LR models were developed using the training set and subsequently evaluated on the validation set. The LR model achieved an accuracy of 84.57%, sensitivity of 82.89%, specificity of 80.10%, positive predictive value of 84%, negative predictive value of 85.06%, and a Yoden index of 0.69. In contrast, the RF model demonstrated superior performance with an accuracy of 89.51%, sensitivity of 90.79%, specificity of 88.37%, positive predictive value of 87.34%, negative predictive value of 91.57%, and a Yoden index of 0.79. Receiver operating characteristic curve analysis revealed an area under the curve of 0.91 for the LR model and 0.94 for the RF model. These findings indicate that the RF model surpasses the LR model in specificity, sensitivity, and accuracy in predicting hospital-acquired multidrug-resistant Gram-negative infections, showcasing its greater potential for clinical application.


Asunto(s)
Antibacterianos , Infección Hospitalaria , Farmacorresistencia Bacteriana Múltiple , Bacterias Gramnegativas , Infecciones por Bacterias Gramnegativas , Humanos , Infección Hospitalaria/microbiología , Infección Hospitalaria/tratamiento farmacológico , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Infecciones por Bacterias Gramnegativas/microbiología , Bacterias Gramnegativas/efectos de los fármacos , Modelos Logísticos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Masculino , Femenino , China , Persona de Mediana Edad , Anciano , Adulto , Bosques Aleatorios
16.
Eur J Surg Oncol ; 50(6): 108321, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38598875

RESUMEN

PURPOSE: The aim of this study was to develop a nomogram specially for predicting overall survival (OS) for Chinese patients with neuroblastoma (NB). METHODS: Patients with pathologically confirmed NB who were newly diagnosed and received treatments at our hospital from October 2013 to October 2021 were retrospectively reviewed. The nomogram for OS were built based on Cox regression analysis. The validation of the prognostic model was evaluated by concordance index (C-index), calibration curves, and decision curve analyses (DCAs). RESULTS: A total of 254 patients with NB were included in this study. They were randomly divided into a training cohort (n = 178) and a validation cohort (n = 76) at a ratio of 7:3. Multivariate analyses revealed that prognostic variables significantly related to the OS were age at diagnosis, bone metastasis, hepatic metastasis, INSS stage, MYCN status and DNA ploidy. The nomogram was constructed based on above 6 factors. The C-index values of the nomogram for predicting 3-year and 5-year OS were 0.926 and 0.964, respectively. The calibration curves of the nomogram showed good consistency between nomogram prediction and actual survival. The DCAs showed great clinical usefulness of the nomograms. Furthermore, patients with low-risk identified by our nomogram had much higher OS than those with high-risk (p < 0.001). CONCLUSION: The nomogram we constructed exhibited good predictive performance and could be used to assist clinicians in their decision-making process.


Asunto(s)
Neoplasias Hepáticas , Neuroblastoma , Nomogramas , Humanos , Neuroblastoma/mortalidad , Neuroblastoma/patología , Neuroblastoma/genética , Neuroblastoma/secundario , Masculino , Femenino , Lactante , Preescolar , Estudios Retrospectivos , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/terapia , Niño , Tasa de Supervivencia , Estadificación de Neoplasias , Neoplasias Óseas/secundario , Neoplasias Óseas/mortalidad , China/epidemiología , Proteína Proto-Oncogénica N-Myc/genética , Pronóstico , Factores de Edad , Modelos de Riesgos Proporcionales
17.
Org Lett ; 26(17): 3552-3556, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38639551

RESUMEN

A formal [3 + 2] annulation of cyclohexadienone-tethered ynals is enabled by an N-heterocyclic carbene (NHC) catalyst, affording a tricyclo[6.2.1.04,11]undecane framework. This study represents the first demonstration of using C═C double bonds as the reaction partner in the NHC-catalyzed annulation of ynals. This strategy is characterized by mild reaction conditions and 100% atom economy as well as high catalytic performance and efficiency.

18.
Cytokine ; 176: 156510, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38308951

RESUMEN

More and more evidence shows that long non-coding RNA (lncRNA) plays an important role in the biological behavior of many kinds of malignant tumors, but the specific function of lncRNA Linc00657 in cervical cancer is still unknown. The purpose of this study is to explore the effect of Linc00657 on the malignant progression of cervical cancer and its potential mechanism. In two kinds of cervical cancer cell lines and normal cervical epithelial cells, qRT-PCR showed increased expression of Linc00657 in cervical cancer cells. Through MTT, clone formation test, flow cytometry, wound healing test and Transwell test, it has been found that overexpression of Linc00657 could promote the proliferation,migration and invasion of cervical cancer cells,and inhibit apoptosis. Through the StarBase database, it was found that there may be a mutual regulatory relationship between Linc00657 and Skp2, and Skp2 may be the downstream target of Linc00657. QRT-PCR detection confirmed that the expression of Skp2 was increased in cervical cancer cells with overexpression of Linc00657. TIMER2 database found that Skp2 was associated with lipid metabolic enzymes and immune cell infiltration. It was found that Linc00657 knockdown inhibited tumor growth and metastasis and inhibited the expression of Skp2 in vivo. In short, our research shows that Linc00657 has carcinogenic properties in cervical cancer, and LINC00657 promotes the occurrence of cervical cancer by up-regulating the expression of Skp2. We predict that Linc00657/mir30s/Skp2 axis plays a role in the malignant progression of cervical cancer. In addition, Skp2 may participate in cancer immune response and promote lymph node metastasis of cervical cancer through lipid reprogramming. These findings also provide promising targets for the diagnosis and treatment of cervical cancer.


Asunto(s)
MicroARNs , ARN Largo no Codificante , Neoplasias del Cuello Uterino , Femenino , Humanos , Línea Celular Tumoral , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Neoplasias del Cuello Uterino/genética , Carcinogénesis/genética , Lípidos , Regulación Neoplásica de la Expresión Génica , Proliferación Celular/genética , Movimiento Celular/genética , MicroARNs/metabolismo , Microambiente Tumoral/genética
19.
Int J Biol Macromol ; 264(Pt 1): 130377, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38395279

RESUMEN

The COVID-19 pandemic caused by SARS-CoV-2 continues to pose a threat to public health, and extensive research by scientists worldwide has also prompted the development of antiviral therapies. The 3C-like protease (3CLpro) is critical for SARS-CoV-2 replication and acts as an effective target for drug development. To date, numerous of natural products have been reported to exhibit inhibitory effects on 3CLpro, which encourages us to identify other novel inhibitors and elucidate their mechanism of action. In this study, we first screened an in-house compound library of 101 natural products using FRET assay, and found that oleuropein showed good inhibitory activity against SARS CoV-2 3CLpro with an IC50 value of 4.18 µM. Further studies revealed that the catechol core is essential for activity and can covalently bind to SARS-CoV-2 3CLpro. Among other 45 catechol derivatives, wedelolactone, capsazepine and brazilin showed better SARS-CoV-2 3CLpro inhibitory activities with IC50 values of 1.35 µM, 1.95 µM and 1.18 µM, respectively. These catechol derivatives were verified to be irreversible covalent inhibitors by time-dependent experiments, enzymatic kinetic studies, dilution and dialysis assays. It also exhibited good selectivity towards different cysteine proteases (SARS-CoV-2 PLpro, cathepsin B and cathepsin L). Subsequently, the binding affinity between brazilin and SARS-CoV-2 3CLpro was determined by SPR assay with KD value of 0.80 µM. Molecular dynamic (MD) simulations study showed the binding mode of brazilin in the target protein. In particular, brazilin displayed good anti-SARS-CoV-2 activity in A549-hACE2-TMPRSS2 cells with EC50 values of 7.85 ± 0.20 µM and 5.24 ± 0.21 µM for full time and post-infection treatments, respectively. This study provides a promising lead compound for the development of novel anti-SARS-CoV-2 drugs.


Asunto(s)
Productos Biológicos , COVID-19 , Humanos , SARS-CoV-2 , Pandemias , Cinética , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/química , Diálisis Renal , Catecoles/farmacología , Antivirales/química , Simulación del Acoplamiento Molecular
20.
PLoS One ; 19(2): e0298295, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38354174

RESUMEN

BACKGROUND: Timeless is well-known for its key role in replication checkpoints. Recent studies reveal the involvement of Timeless and specificity protein (SP) 1 in human malignancies. However, no evidence proved the interaction between SP3 and Timeless in lung adenocarcinoma (LUAD). METHODS: The expression and clinical significance of Timeless were analyzed using the LUAD dataset downloaded from the Cancer Genome Atlas (TCGA). Lentivirus-mediated Timeless knockdown in A549 cells was used to examine the role of Timeless in cell proliferation and pemetrexed (PEM) resistance. Transcription factors (TFs) bound to the Timeless promoter were identified by DNA pull-down technology with HPLC-MS/MS analysis and analyzed by the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. Dual-luciferase reporter assay was used to determine the activity of SP3 in Timeless transcription. RESULTS: Timeless was overexpressed in LUAD samples, and it could serve as a potential diagnostic or prognostic biomarker for LUAD patients. shTimeless-mediated knockdown of Timeless reduced cell viability and proliferation and sensitized PEM-resistant A549 cells to PEM. Four fragments (F1: 1-373 bp), (F2: 374-962 bp), (F4: 1274-1645 bp), and (F5: 1646-2000bp) were confirmed as the TF binding profiles of the Timeless promoter. KEGG analysis showed that the TFs bound to the Timeless promoter had relevance to spliceosome, RNA transport, and mRNA surveillance pathways. SP3 promoted the transcription of Timeless via the F2 fragment (374-962 bp) binding motif. CONCLUSION: Upregulation of Timeless mediated by SP3 promotes LUAD cell proliferation, providing evidence to support that targeting the SP3/Timeless axis may be a potential therapeutic strategy against LUAD.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Adenocarcinoma del Pulmón/patología , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/patología , Espectrometría de Masas en Tándem
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