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1.
Nat Metab ; 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39322747

RESUMEN

The crucial role of gut microbiota in shaping immunotherapy outcomes has prompted investigations into potential modulators. Here we show that oral administration of acarbose significantly increases the anti-tumour response to anti-PD-1 therapy in female tumour-bearing mice. Acarbose modulates the gut microbiota composition and tryptophan metabolism, thereby contributing to changes in chemokine expression and increased T cell infiltration within tumours. We identify CD8+ T cells as pivotal components determining the efficacy of the combined therapy. Further experiments reveal that acarbose promotes CD8+ T cell recruitment through the CXCL10-CXCR3 pathway. Faecal microbiota transplantation and gut microbiota depletion assays indicate that the effects of acarbose are dependent on the gut microbiota. Specifically, acarbose enhances the efficacy of anti-PD-1 therapy via the tryptophan catabolite indoleacetate, which promotes CXCL10 expression and thus facilitates CD8+ T cell recruitment, sensitizing tumours to anti-PD-1 therapy. The bacterial species Bifidobacterium infantis, which is enriched by acarbose, also improves response to anti-PD-1 therapy. Together, our study endorses the potential combination of acarbose and anti-PD-1 for cancer immunotherapy.

2.
Phytochemistry ; : 114273, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39245154

RESUMEN

Three previously undescribed pyrrolizidinone alkaloids, penicipyrrolizidinones A and B (1 and 2), possessing an unprecedented 2-methyl-2-(oct-6-enoyl)pyrrolizidin-3-one skeleton, and penicipyrrolizidinone C (3), featuring a rare 1-alkenyl-2-methyl-pyrrolizidin-3,7-dione skeleton, together with four known pyrrolidine derivatives (4-7) were isolated from the mangrove-derived fungus Penicillium sp. DM27. Their structures were elucidated through comprehensive spectroscopic analysis, theoretical calculations of ECD spectra, and the modified Mosher's method. A plausible biosynthetic pathway for penicipyrrolizidinones A-C (1-3) was proposed. Compounds 4 and 5 exhibited moderate cytotoxicity against B16-F10 melanoma cells with IC50 values of 10.5 µM and 15.5 µM, respectively.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 325: 125107, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39260242

RESUMEN

In this work, derived from vanillin and imidazo-pyridin backbone, a fluorescent probe IPV-Cys was developed for imaging the cysteine (Cys) level in living pulmonary cells under oxygen supply variation. By mimicking the oxygen supply variation in both the solution test and cellular imaging, the optical performance and imaging effect of IPV-Cys was investigated. In the solution system, the oxygen supply variation caused no impact on the reporting signals. The fluorescence reporting signal intensity at 490 nm suggested the enhancement along with the increase of the Cys concentration. The advantages of IPV-Cys included relatively high sensitivity, high stability, and high selectivity. On the basis of the low cyto-toxicity, IPV-Cys achieved the monitoring the endogenous Cys level in in living pulmonary cells and the impact of the oxygen supply variation by reporting fluorescence signals. The information here was meaningful for both the pre-clinical diagnosis and surgical techniques.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 325: 125043, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39236567

RESUMEN

The performance of organic solar cell (OSC) devices has been significantly enhanced by the dramatic evolution of A-D-A type non-fullerene acceptors (NFAs). Nevertheless, the structure-property-performance relationship of NFAs in the OSC device is unclear. Here, the intrinsic design factors of isomeric, fluorination and π-conjunction curtailing on the photophysical properties of benzodi (thienopyran) (BDTP) (named NBDTP-M, NBDTTP-M, NBDTP-Fin, and NBDTP-Fout)-based NFAs are discussed. The results show that fluorination on the terminal group of NBDTP-Fout could effectively decrease the highest occupied orbital (HOMO) energy level and the lowest unoccupied orbital (LUMO) energy level. And the long π-conjugated donor unit for NBDTTP-M could increase the HOMO energy level and bring a small HOMO-LUMO energy bandgap. Meanwhile, the substitution of external oxygen atoms and the fluorine atoms in the terminal group could introduce positive changes to the electrostatic potential of the NBDTP-Fout, favouring the charge separation at the donor/acceptor interface. Moreover, the structural design of external oxygen atom substitution, fluorination on the terminal group and curtailed π-conjugated donor unit could decrease the electron vibration-coupling of exciton diffusion, exciton dissociation and electronic transfer processes. The suppression of the exciton decay and charge recombination in those high-performance NFAs indicate that the investigated molecular designs could be effective for further improvement of OSCs.

5.
J Med Chem ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39258312

RESUMEN

The FLT3-ITD (internal tandem duplication) mutant has been a promising target for acute myeloid leukemia (AML) drug discovery but is now facing the challenge of resistance due to point mutations. Herein, we have discovered a type II FLT3 inhibitor, SILA-123. This inhibitor has shown highly potent inhibitory effects against FLT3-WT (IC50 = 2.1 nM) and FLT3-ITD (IC50 = 1.0 nM), tumor cells with the FLT3-ITD mutant such as MOLM-13 (IC50 = 0.98 nM) and MV4-11 (IC50 = 0.19 nM), as well as BaF3 cells associated with the FLT3-ITD mutant and point mutations like BaF3-FLT3-ITD-G697R (IC50 = 3.0 nM). Moreover, SILA-123 exhibited promising kinome selectivity against 310 kinases (S score (10) = 0.06). In in vivo studies, SILA-123 significantly suppressed the tumor growth in MV4-11 (50 mg/kg/d, TGI = 87.3%) and BaF3-FLT3-ITD-G697R (50 mg/kg/d, TGI = 60.0%) cell-inoculated allograft models. Our data suggested that SILA-123 might be a promising drug candidate for FLT3-ITD-positive AML.

6.
Front Pharmacol ; 15: 1437773, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39246657

RESUMEN

Introduction: Chlorogenic acid (CGA) has been identified to possess salient anti-inflammatory, antioxidant, and anticancer attributes. However, its application is limited by its instability and low bioavailability. Liposomes have been considered effective pharmaceutical delivery vehicles due to their ability to continuously release loaded drugs, improve drug stability, and display good biocompatibility. They can be easily modified by other small molecules to acquire additional biological functions. In this study, we developed and characterized folic acid-TPGS-modified chlorogenic acid liposome (FTCLP) and evaluated its anti-inflammatory activity. Methods: The successful encapsulation of CGA within FTCLP was confirmed through examination using electron microscopy, fourier-transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). The in vitro release characteristics of FTCLP were evaluated using the dialysis bag membrane method. Meanwhile, a dextran sulfate sodium (DSS) -induced colitis model was employed to investigate the anti-inflammatory effect of FTCLP and its mechanism. Results: The FTCLP exhibited an encapsulation efficiency (EE) of 84.85 ± 1.20% and a drug loading (DL) of 11.67 ± 0.04%. The particle size of FTCLP was determined to be 150.63 ± 0.71 nm, with a polydispersity index (PDI) of 0.198 ± 0.02 and a zeta potential of 2.61 ± 0.38 mV. The in vitro release profile followed the Higuchi model, indicating sustained-release characteristics. The in vivo study demonstrated that FTCLP treatment was effective in improving the symptoms of DSS-induced inflammatory response, as evidenced by mitigation of weight loss, reduction in the disease activity index (DAI) score, restoration of colon length, and attenuation of colon tissue damage. Furthermore, the levels of pro-inflammatory cytokines, including interferon-gamma (INF-γ), interleukin-1 beta (IL-1ß), and interleukin-6 (IL-6), were markedly diminished in both the serum and colon tissue. FTCLP was also observed to suppress the expression of INF-γ, IL-1ß, IL-6, tumor necrosis factor-alpha (TNF-α), and nuclear factor kappa B (NF-κB) p65, while concomitantly upregulating the expression of Janus kinase (JAK) and signal transducer and activator of transcription 3 (STAT3). Besides, the administration of FTCLP was found to result in an increase in the abundance of Lactobacillaceae and Peptostreptococcaceae, while decreasing the abundance of Bacteroidaceae, Rikenellaceae, and Helicobacteraceae. Conclusion: Following encapsulation of CGA within liposomes, FTCLP revealed favorable stability and sustained release properties, and enhanced the anti-inflammatory effects by modulating multiple inflammation-related biomarkers. FTCLP has the potential to be a safe and effective drug for targeted therapy of colitis.

7.
Anal Sci ; 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39242486

RESUMEN

Herein, by combining the benzofuranone-derived fluorophore and the carbamate recognition group, a fluorescent probe named BFO-CarE was developed for monitoring the carboxylesterase (CarE) level in pulmonary cells under the permissive hypercapnia condition. It showed a notable fluorescence response towards CarE at 570 nm under the excitation of 510 nm. The in-solution tests revealed the advantages of BFO-CarE including high sensitivity, high specificity, relatively rapid response, and high steadiness. It was also low-toxic upon the pulmonary cell lines. During the intracellular imaging in pulmonary cells, BFO-CarE achieved the monitoring of the CarE level in both inhibition and activation status. In particular, BFO-CarE realized the visualization of the affection of the permissive hypercapnia condition on the CarE level, which indicated the hypoxia tolerance of CarE. This work was informative for investigating the impact of hypoxia in pulmonary cells, and the corresponding anaesthesia-related approaches.

8.
Biochim Biophys Acta Mol Basis Dis ; 1870(8): 167493, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39233261

RESUMEN

The immune landscape of distant unablated tumors following insufficient microwave ablation (iMWA) in hepatocellular carcinoma (HCC) remains to be clarified. The objective of this study is to define the abscopal immune landscape in distant unablated tumor before and after iMWA for HCC. Two treatment-naive patients were recruited for tumor tissue sampling, of each with two HCC lesions. Tumor samples were obtained at before and after microwave ablation in distant unablated sites for single-cell RNA sequencing (scRNA-seq). Mouse model with bilateral hepatoma tumors were developed, and distant unablated tumors were analyzed using multicolor immunofluorescence, RNA sequencing and flow cytometry. The scRNA-seq revealed that a reduced proportion of CD8+ T cells and an increased proportion of myeloid-derived suppressor cells (MDSCs) were observed in the distant unablated tumor microenvironment (TME). A notable disruption was observed in the lipid metabolism of tumor-associated immune cells, accompanied by an upregulated expression of CD36 in tumor-infiltrating immune cells in distant unablated tumor. The administration of a CD36 inhibitor has been demonstrated to ameliorate the adverse effects induced by iMWA, primarily by reinstating the anti-tumor responses of T cells in distant unablated tumor. These findings explain the recurrence and progression of tumors after iMWA and provide a new target of immunotherapy for HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Microondas , Células Supresoras de Origen Mieloide , Microambiente Tumoral , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , Células Supresoras de Origen Mieloide/inmunología , Células Supresoras de Origen Mieloide/metabolismo , Animales , Microondas/uso terapéutico , Ratones , Microambiente Tumoral/inmunología , Humanos , Masculino , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Ratones Endogámicos C57BL
9.
Cancer Cytopathol ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39264831

RESUMEN

BACKGROUND: Trichorhinophalangeal syndrome 1 (TRPS1) expression in primary breast and other solid tumors has been investigated but its role as a marker in metastatic tumors is unclear. The objective of this study was to evaluate the sensitivity and specificity of TRPS1 as a breast cancer immunomarker in metastatic tumors that originated from breast, Müllerian, lung, gastrointestinal (GI), and pancreatic primary tumors with cell blocks from fine-needle aspiration (FNA) and effusion specimens. METHODS: Cell blocks were immunostained with anti-TRPS1 monoclonal antibody (clone EPR16171). Histochemical scores (H scores) (proportion × intensity; range, 0-300) were assigned; H scores of ≥10 were considered positive. Overall, 160 specimens were examined, including 127 FNAs (35 breast, 25 Müllerian, 36 lung, and 31 GI and pancreatic carcinomas) and 33 effusion specimens (18 breast, 12 Müllerian, one lung, and two GI carcinomas). RESULTS: TRPS1 was positive in 51 of 53 (96%) metastatic breast carcinomas and in 28 of 107 (26.2%) nonbreast metastatic tumors. Metastatic breast carcinoma showed the highest mean H score of 247.35, compared to 45.36 in Müllerian, 8.4 in lung, and 5.88 in GI tumors. The sensitivity and specificity of TRPS1 for identifying a breast origin in metastatic tumors was 96.22% and 72.89%, respectively. CONCLUSIONS: Despite high overall sensitivity, TRPS1 showed lower specificity as a breast immunomarker because of its expression in nonbreast tumors. The mean H score in nonbreast tumors was significantly lower than in metastatic breast tumors. It is important to recognize the broad range of expression of TRPS1 in metastatic breast and nonbreast tumors to avoid an incorrect determination of a metastatic tumor's organ of origin.

10.
Mol Neurobiol ; 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39347895

RESUMEN

Current research lacks comprehensive investigations into the potential causal link between mitochondrial-related genes and the risk of neurodegenerative diseases (NDDs). We aimed to identify potential causative genes for five NDDs through an examination of mitochondrial-related gene expression levels. Through the integration of summary statistics from expression quantitative trait loci (eQTL) datasets (human blood and brain tissue), mitochondrial DNA copy number (mtDNA-CN), and genome-wide association studies (GWAS) datasets of five NDDs from European ancestry, we conducted a Mendelian randomization (MR) analysis to explore the potential causal relationship between mitochondrial-related genes and Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Lewy body dementia (LBD). Sensitivity analysis and Bayesian colocalization were employed to validate this causal relationship. Through MR analysis, we have identified potential causal relationships between 12 mitochondria-related genes and AD, PD, ALS, and FTD overlapping with motor neuron disease (FTD_MND) in human blood or brain tissue. Bayesian colocalization analysis further confirms 9 causal genes, including NDUFS2, EARS2, and MRPL41 for AD; NDUFAF2, MALSU1, and METTL8 for PD; MYO19 and MRM1 for ALS; and FASTKD1 for FTD_MND. Importantly, in both human blood and brain tissue, NDUFS2 exhibits a significant pathogenic effect on AD, while NDUFAF2 demonstrates a robust protective effect on PD. Additionally, the mtDNA-CN plays a protected role in LBD (OR = 0.62, p = 0.031). This study presents evidence establishing a causal relationship between mitochondrial dysfunction and NDDs. Furthermore, the identified candidate genes may serve as potential targets for drug development aimed at preventing NDDs.

11.
Nano Lett ; 24(36): 11170-11178, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39148056

RESUMEN

Functionally diverse devices with artificial neuron and synapse properties are critical for neuromorphic systems. We present a two-terminal artificial leaky-integrate-fire (LIF) neuron based on 6 nm Hf0.1Zr0.9O2 (HZO) antiferroelectric (AFE) thin films and develop a synaptic device through work function (WF) engineering. LIF neuron characteristics, including integration, firing, and leakage, are achieved in W/HZO/W devices due to the accumulated polarization and spontaneous depolarization of AFE HZO films. By engineering the top electrode with asymmetric WFs, we found that Au/Ti/HZO/W devices exhibit synaptic weight plasticity, such as paired-pulse facilitation and long-term potentiation/depression, achieving >90% accuracy in digit recognition within constructed artificial neural network systems. These findings suggest that AFE HZO capacitor-based neurons and WF-engineered artificial synapses hold promise for constructing efficient spiking neuron networks and artificial neural networks, thereby advancing neuromorphic computing applications based on emerging AFE HZO devices.

13.
J Dig Dis ; 25(7): 424-435, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39104049

RESUMEN

OBJECTIVE: We aimed to compare the clinical and endoscopic characteristics of sessile serrated lesions (SSLs) with dysplasia/carcinoma (SSLD/Cs) and SSLs without dysplasia in this systematic review and meta-analysis. METHODS: MEDLINE, EMBASE, and Cochrane Library databases and Clinicaltrials.gov were searched for relevant studies published up to August 28, 2023. The primary outcome was lesion size in SSLD/Cs and SSLs without dysplasia. The secondary outcomes included risk of dysplasia/carcinoma, morphology (classified based on the Paris classification), and lesion features such as mucus cap and nodules/protrusions in the two groups. RESULTS: Thirteen studies with 14 381 patients were included. The proportion of SSLD/Cs ≥10 mm was significantly higher than that of SSLs without dysplasia (odds ratio [OR] 3.82, 95% confidence interval [CI] 1.21-12.02, p = 0.02). There was no significant difference in the risk of dysplasia/carcinoma between the proximal (OR 0.80, 95% CI 0.57-1.14) and distal colon (OR 1.25, 95% CI 0.88-1.77, p = 0.21). The 0-Ip (OR 2.47, 95% CI 1.50-4.09) and 0-IIa + Is (OR 10.38, 95% CI 3.08-34.98) morphologies were more prevalent among SSLD/Cs, whereas the 0-IIa morphology (OR 0.38, 95% CI 0.22-0.65) was more prevalent among SSLs without dysplasia (all p < 0.001). Furthermore, mucus cap (OR 0.61, 95% CI 0.42-0.89, p = 0.01) was more common among SSLs without dysplasia, whereas nodules/protrusions (OR 7.80, 95% CI 3.07-19.85, p < 0.001) were more common in SSLD/Cs. CONCLUSION: SSLs >10 mm, 0-Ip or 0-IIa + Is morphologies, and those with nodules/protrusions are significantly associated with dysplasia/carcinoma.


Asunto(s)
Pólipos del Colon , Colonoscopía , Neoplasias Colorrectales , Humanos , Neoplasias Colorrectales/patología , Pólipos del Colon/patología , Carcinoma/patología , Femenino
14.
World J Clin Cases ; 12(22): 5159-5167, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39109043

RESUMEN

BACKGROUND: Lower extremity lymphedema is a common complication following treatment for gynecological malignancies. Its incidence rate can reach up to 70%, affecting ~20 million people worldwide. However, specialized treatment centers are scarce, and there is a lack of consensus on treatment approaches. Furthermore, there are even fewer reports on the systematic and effective treatment of severe lymphedema with malformations. Effective management of this condition remains a significant challenge for clinicians. CASE SUMMARY: A 40-year-old woman developed bilateral leg swelling 6 years after receiving treatment for endometrial cancer. Since August 2018, she experienced > 30 episodes of lymphangitis. Upon presentation, she exhibited bilateral leg swelling and deformation, with four large swellings in the posterior thigh that impeded movement, and pain in the limbs. Skin manifestations included lichenoid lesions and features of deep sclerosis. Radionuclide lymphoscintigraphy confirmed the diagnosis of lower limb lymphedema. After 6 mo of complex decongestive therapy (CDT) and three lymphaticovenous anastomosis (LVA) treatments, the patient lost 49 kg in weight. She also experienced a maximum circumference reduction of 35.2 cm in the left lower limb and 37.5 cm in the right lower limb. The leg pain disappeared, her swelling significantly decreased, and she regained the ability to walk, cycle, and run normally. CONCLUSION: The combined application of CDT and LVA therapy demonstrates significant positive effects in the treatment of severe, deformed stage III lymphedema.

15.
J Inflamm Res ; 17: 5093-5112, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39099664

RESUMEN

Background: Sepsis continues to exert a significant impact on morbidity and mortality in clinical settings, with immunosuppression, multi-organ failure, and disruptions in gut microbiota being key features. Although rheinic acid and tanshinone IIA show promise in mitigating macrophage apoptosis in sepsis treatment, their precise targeting of macrophages remains limited. Additionally, the evaluation of intestinal flora changes following treatment, which plays a significant role in subsequent cytokine storms, has been overlooked. Leveraging the innate inflammation chemotaxis of tumor cell-derived exosomes allows for their rapid recognition and uptake by activated macrophages, facilitating phenotypic changes and harnessing anti-inflammatory effects. Methods: We extracted exosomes from H1299 cells using a precipitation method. Then we developed a tumor cell-derived exosomal hybrid nanosystem loaded with rhubarbic acid and tanshinone IIA (R+T/Lipo/EXO) for sepsis treatment. In vitro studies, we verify the anti-inflammatory effect and the mechanism of inhibiting cell apoptosis of nano drug delivery system. The anti-inflammatory effects, safety, and modulation of intestinal microbiota by the nanoformulations were further validated in the in vivo study. Results: Nanoformulation demonstrated enhanced macrophage internalization, reduced TNF-α expression, inhibited apoptosis, modulated intestinal flora, and alleviated immunosuppression. Conclusion: R+T/Lipo/EXO presents a promising approach using exosomal hybrid nanosystems for treating sepsis.

16.
J Colloid Interface Sci ; 677(Pt A): 1005-1015, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39128284

RESUMEN

Heterostructures endow electrochemical hybrids with promising energy storage properties owing to synergistic effects and interfacial interaction. However, developing a facile but effective approach to maximize interface effects is crucial but challenging. Herein, a bimetallic sulfide/carbon heterostructure is realized in a confined carbon network via a high-throughput template-assisted strategy to induce highly active and stable electrode architecture. The designed heterostructures not only yield abundant interconnected Co9S8/MoS2/N-doped carbon (Co9S8/MoS2/NC) heterojunctions with continuous channels for ion/electron transfer but maintain excellent conversion reversibility. Serving as anode for sodium storage, the Co9S8/MoS2/NC framework displayed excellent sodium storage properties (reversible capacity of 480 mAh/g after 100 cycles at 0.2 A/g and 286.2 mAh/g after 500 cycles at 2 A/g). Given this, this study can guide future design protocols for interface engineering by forming dynamic channels of conversion reaction kinetics for potential applications in high-performance electrodes.

17.
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.

18.
Biochem Biophys Res Commun ; 738: 150546, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39154554

RESUMEN

A new cocrystalline form of metronidazole (MET) with propyl gallate (PRO), referred to as MET-PRO, has been successfully synthesized and characterized. Structural characterization reveals that MET and PRO are present in a 1:1 ratio within the cocrystal lattice, with one water molecule equivalent incorporated into the structure. This arrangement facilitates the formation of MET-PRO heterodimers and multiple stable units, collectively constructing a three-dimensional supramolecular network. The solubility and permeability of the current cocrystal, along with the parent drug MET, are evaluated under physiological pH conditions. Experimental findings reveal that MET within the cocrystal exhibits a 1.54-2.37 folds increase in solubility and approximately a threefold improvement in permeability compared to its standalone form. Intriguingly, these concurrent enhancements in the physicochemical properties of MET lead to augmented antibacterial activity in vitro, evidenced by a reduction in minimum inhibitory concentration. Even more intriguingly, the enhanced physicochemical properties observed in vitro for the current cocrystal translate into tangible pharmacokinetic benefits in vivo, characterized by prolonged half-life and enhanced bioavailability. Consequently, this research not only introduces a fresh crystal structure for antibacterial medication but also presents approach for optimizing drug properties across in vitro and in vivo settings, while concurrently bolstering the antibacterial effectiveness of MET through pharmaceutical cocrystallization techniques.

19.
RSC Adv ; 14(35): 25289-25300, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39139236

RESUMEN

Chlorogenic acid (CGA), a polyphenol compound, exhibits excellent anti-oxidative, anti-hypoxic, antibacterial, antiviral, and anti-inflammatory activities, however the bioactivity of it has not been fully utilized in vivo due to its instability and low bioavailability. To address these issues, we prepared and characterized CGA-TPGS-LP, which is a TPGS-modified liposome loaded with CGA. The pharmacokinetics of CGA-TPGS-LP were studied in rats after oral administration. CGA-TPGS-LP was fabricated using a combination of thin film dispersion and ion-driven methods. The liposomes were observed to be uniformly small and spherical in shape. Their membranes were composed of lecithin, cholesterol, and TPGS lipophilic head with a TPGS hydrophilic tail chain coating on its surface. The loading efficiency and encapsulation efficiency were found to be 11.21% and 83.22%, respectively. The physicochemical characterisation demonstrated that the CGA was present in an amorphous form and retained its original structural state within the liposomal formulation. The stability of CGA was significantly improved by fabricating TPGS-LP. CGA-TPGS-LP exhibited good sustained-release properties in both simulated gastric and intestinal fluids. Following oral administration, ten metabolites were identified in rat plasma using UPLC-QTOF-MS. UPLC-QqQ-MS/MS quantitative analysis demonstrated that the oral bioavailability of CGA encapsulated in TPGS-modified liposomes was enhanced by 1.52 times. In addition, the three main metabolites of CGA had higher plasma concentrations and slower degradation rate. These results demonstrate that TPGS-modified liposomes could be a feasible strategy to further enhance the oral bioavailability of CGA, facilitating its clinical use.

20.
Int J Numer Method Biomed Eng ; : e3862, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39142807

RESUMEN

Surgery of jawbones has a high potential risk of causing complications associated with temporomandibular joint disorder (TMD). The objective of this study was to investigate the effects of two drive modeling methods on the biomechanical behavior of the temporomandibular joint (TMJ) including articular disc during mandibular movements. A finite element (FE) model from a healthy human computed tomography was used to evaluate TMJ dynamic using two methods, namely, a conventional spatial-oriented method (displacement-driven) and a compliant muscle-initiated method (masticatory muscle-driven). The same virtual FE model was 3D printed and a custom designed experimental platform was established to validate the accuracy of experimental and theoretical results of the TMJ biomechanics during mandibular movements. The results show that stress distributed to TMJ and articular disc from mandibular movements provided better representation from the muscle-driving approach than those of the displacement-driven modeling. The simulation and experimental data exhibited significant strong correlations during opening, protrusion, and laterotrusion (with canonical correlation coefficients of 0.994, 0.993, and 0.932, respectively). The use of muscle-driven modeling holds promise for more accurate forecasting of stress analysis of TMJ and articular disc during mandibular movements. The compliant approach to analyze TMJ dynamics would potentially contribute to clinic diagnosis and prediction of TMD resulting from occlusal disease and jawbone surgery such as orthognathic surgery or tumor resection.

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