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1.
BMC Cancer ; 24(1): 576, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38730348

ABSTRACT

OBJECTIVE: Nasopharyngeal adenoid cystic carcinoma (NACC) is a rare malignancy with special biological features. Controversies exist regarding the treatment approach and prognostic factors in the IMRT era. This study aimed to evaluate the long-term outcomes and management approaches in NACC. METHODS: Fifty patients with NACC at our institution between 2010 and 2020 were reviewed. Sixteen patients received primary radiotherapy (RT), and 34 patients underwent primary surgery. RESULTS: Between January 2010 and October 2020, a total of 50 patients with pathologically proven NACC were included in our analysis. The median follow-up time was 58.5 months (range: 6.0-151.0 months). The 5-year overall survival rate (OS) and progression-free survival rate (PFS) were 83.9% and 67.5%, respectively. The 5-year OS rates of patients whose primary treatment was surgery and RT were 90.0% and 67.3%, respectively (log-rank P = 0.028). The 5-year PFS rates of patients whose primary treatment was surgery or RT were 80.8% and 40.7%, respectively (log-rank P = 0.024). Multivariate analyses showed that nerve invasion and the pattern of primary treatment were independent factors associated with PFS. CONCLUSIONS: Due to the relative insensitivity to radiation, primary surgery seemed to provide a better chance of disease control and improved survival in NACC. Meanwhile, postoperative radiotherapy should be performed for advanced stage or residual tumours. Cranial nerve invasion and treatment pattern might be important factors affecting the prognosis of patients with NACC.


Subject(s)
Carcinoma, Adenoid Cystic , Nasopharyngeal Neoplasms , Radiotherapy, Intensity-Modulated , Humans , Carcinoma, Adenoid Cystic/radiotherapy , Carcinoma, Adenoid Cystic/mortality , Carcinoma, Adenoid Cystic/pathology , Carcinoma, Adenoid Cystic/surgery , Male , Female , Radiotherapy, Intensity-Modulated/methods , Middle Aged , Adult , Nasopharyngeal Neoplasms/radiotherapy , Nasopharyngeal Neoplasms/mortality , Nasopharyngeal Neoplasms/pathology , Aged , Retrospective Studies , Nasopharyngeal Carcinoma/radiotherapy , Nasopharyngeal Carcinoma/mortality , Nasopharyngeal Carcinoma/pathology , Young Adult , Prognosis , Survival Rate , Treatment Outcome , Follow-Up Studies , Adolescent , Progression-Free Survival
2.
J Asthma ; : 1-8, 2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38470879

ABSTRACT

OBJECTIVE: To evaluate the economic value of mepolizumab as an add-on therapy to the standard of care (SoC) for patients with severe eosinophilic asthma in China. METHODS: A Markov model with three health conditions was constructed to calculate the incremental cost per quality-adjusted life year (QALY) in mepolizumab with SoC and SoC only groups from the perspective of the Chinese healthcare system throughout an entire lifespan. The model was populated with local costs, while efficacy parameters were obtained from the global Phase III MENSA trial and mortality was derived from two surveys. One-way and probabilistic sensitivity analyses were conducted. Additional scenario analysis was used to estimate the cost-effectiveness impact of changes in the price of mepolizumab. RESULTS: Over the lifetime treatment horizon, the incremental cost-effectiveness ratio (ICER) of mepolizumab plus SoC compared to SoC alone was $170 648.73 per QALY. Sensitivity analyses focused on these results. Scenario analysis showed that mepolizumab would require a price reduction of at least 82% to reach the current willingness-to-pay (WTP=$38 223.34/QALY) threshold. CONCLUSION: Mepolizumab is not a cost-effective healthcare resource in China at its current pricing.

3.
Environ Sci Pollut Res Int ; 31(11): 17481-17493, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38342832

ABSTRACT

Excessive phosphorus will lead to eutrophication in aquatic environment; the efficient removal of phosphorus is crucial for wastewater engineering and surface water management. This study aimed to fabricate a nanorod-like sepiolite-supported MgO (S-MgO) nanocomposite with high specific surface area for efficient phosphate removal using a facile microwave-assisted method and calcining processes. The impact of solution pH, adsorbent dosage, contact time, initial phosphate concentrations, Ca2+ addition, and N/P ratio on the phosphate removal was extensively examined by the batch experiments. The findings demonstrated that the S-MgO nanocomposite exhibited effective removal performance for low-level phosphate (0 ~ 2.0 mM) within the pH range of 3.0 ~ 10.0. Additionally, the nanocomposite can synchronously remove phosphate and ammonium in high-level nutrient conditions (> 2.0 mM), with the maximum removal capacities of 188.49 mg P/g and 89.78 mg N/g. Quantitative and qualitative analyses confirmed the successful harvesting of struvite in effluent with high-phosphate concentrations, with the mechanisms involved attributed to a synergistic combination of sorption and struvite crystallization. Due to its proficient phosphate removal efficiency, cost-effectiveness, and substantial removal capacity, the developed S-MgO nanocomposite exhibits promising potential for application in phosphorus removal from aquatic environments.


Subject(s)
Magnesium Silicates , Nanocomposites , Water Pollutants, Chemical , Phosphorus/chemistry , Struvite/chemistry , Magnesium Oxide , Nitrogen , Phosphates/chemistry
4.
Cureus ; 16(1): e52063, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38344586

ABSTRACT

Hypokalemic Periodic Paralysis Type 2 (HOKPP2) is a rare autosomal dominant disorder characterized by recurrent episodes of muscle weakness, paralysis, and hypokalemia. In this case report, we present the clinical details of a 49-year-old female diagnosed with HOKPP2. Genetic testing revealed a heterozygous mutation in the Sodium Voltage-Gated Channel Alpha Subunit 4 (SCN4A) gene, confirming the diagnosis of HOKPP2. Management strategies, including potassium supplementation and lifestyle modifications, were implemented, resulting in a significant decrease in the frequency of symptomatic episodes. This case highlights the importance of considering HOKPP2 in patients with recurrent muscle weakness, particularly those with a familial history of similar symptoms. Furthermore, it underscores the crucial role of genetic testing in guiding patient management and facilitating genetic counseling.

5.
Anim Biosci ; 37(1): 95-104, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37905322

ABSTRACT

OBJECTIVE: In the present study, we aimed to investigate the effects of enzymolysis fermentation of Chinese herbal medicines (CHMs) on egg production performance, egg quality, lipid metabolism, serum reproductive hormone levels, and the mRNA expression of the ovarian hormone receptor of laying hens in the late-laying stage. METHODS: A total of 360 Hy-Line Brown laying hens (age, 390 days) were randomly categorized into four groups. Hens in the control (C) group were fed a basic diet devoid of CHMs, the crushed CHM (CT), fermented CHM (FC), and enzymatically fermented CHM (EFT) groups received diets containing 2% crushed CHM, 2% fermented CHM, and 2% enzymatically fermented CHM, respectively. RESULTS: Compared with crushed CHM, the acid detergent fiber, total flavonoids, and total saponins contents of fermented CHM showed improvement (p<0.05); furthermore, the neutral and acid detergent fiber, total flavonoids, and total saponins contents of enzymatically fermented CHM improved (p<0.05). At 5 to 8 weeks, hens in the FC and EFT groups showed increased laying rates, haugh unit, albumin height, yolk color, shell thickness, and shell strength compared with those in the C group (p<0.05). Compared with the FC group, the laying rate, albumin height, and Shell thickness in the EFT group was increased (p<0.05). Compared with the C, CT, and FC groups, the EFT group showed reduced serum total cholesterol and increased serum luteinizing hormone levels and mRNA expressions of follicle stimulating hormone receptor and luteinizing hormone receptor (p<0.05). CONCLUSION: These results indicated that the ETF group improved the laying rate and egg quality and regulated the lipid metabolism in aged hens. The mechanism underlying this effect was likely related to cell wall degradation of CHM and increased serum levels of luteinizing hormone and mRNA expression of the ovarian hormone receptor.

6.
Chinese Pharmacological Bulletin ; (12): 426-430, 2024.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1013652

ABSTRACT

Glucagon-like peptide-1 ( GLP-1 ) is secreted by gut enteroendocrine cells. GLP-1 receptor agonists ( GLP-1 RAs) control glucose-related augmentation of insulin and suppress glu-cagon secretion. GLP-lRAs also inhibit gastric emptying, food intake and limit weight gain. In the past decade, significant progresses have been made in the investigation on the effects of GLP-1 RAs on cardiovascular system. The potential advantages of oral small-molecule GLP-1 RAs could improve the application of this class of drugs. This review highlights the multiple cardiovascular profiles of GLP-1 RAs in the treatment of cardiovascular diseases to provide new insights into cardiovascular benefits of GLP-1 RAs.

7.
International Eye Science ; (12): 545-550, 2024.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1012818

ABSTRACT

In recent years, the combined surgery of phacoemulsification, intraocular lens implantation, and goniosychialysis has gradually emerged as a primary and effective approach in treating primary angle-closure glaucoma with cataracts. However, with the continuous progress of medical technology, postoperative intraocular pressure control is no longer the sole pursuit. Patients increasingly aspire to achieve higher postoperative visual quality. In order to ensure that patients attain a better refractive status and higher visual quality postoperatively, it is essential to minimize the negative impact caused by primary angle-closure glaucoma. This involves personalized selection of different intraocular lenses or calculation formulas,etc. Evaluation metrics for visual quality encompass visual acuity, contrast sensitivity, higher-order aberrations, subjective perception, etc. Therefore, this paper provides a comprehensive review of postoperative refractive shift, higher-order aberrations, contrast sensitivity and their influencing factors, and the selection of intraocular lenses for patients undergoing combined surgery for primary angle-closure glaucoma with cataracts.

8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 31(6): 1750-1756, 2023 Dec.
Article in Chinese | MEDLINE | ID: mdl-38071056

ABSTRACT

OBJECTIVE: To investigate the genetic results of whole exome sequencing of bone marrow from new onset multiple myeloma (MM) patients to analyze the process of genetic clonal evolution in MM patients. METHODS: Genomic DNA was extracted from bone marrow samples of 15 MM patients and the whole exomes sequencing was performed using next generation sequencing technology. Using own buccal cells as germline controls, combinated with clinical information, the mutation profile of genes from high-risk asymptomatic myeloma to symptomatic myeloma were analyzed, and genes that may be associated with the efficacy and side effects of bortezomib were screened. RESULTS: Except for two patients in whom no peripheral neuropathy was observed after a short treatment period, other patients peripheral neuropathy developed of various degrees during treatment with bortezomib containing chemotherapy, and the vast majority of patients achieved remission after receiving this bortezomib-related chemotherapy regimen. All patients had comparable levels of the inherited mutations number, but the somatic mutations was correlated with disease evolution. CONCLUSION: different gene "mutational spectra" exist in myeloma patients at different stages and are associated with progression through all stages of the disease.


Subject(s)
Multiple Myeloma , Humans , Multiple Myeloma/genetics , Multiple Myeloma/drug therapy , Bortezomib/therapeutic use , Bone Marrow , Exome Sequencing , Mouth Mucosa , Antineoplastic Combined Chemotherapy Protocols/therapeutic use
9.
World J Clin Cases ; 11(35): 8291-8299, 2023 Dec 16.
Article in English | MEDLINE | ID: mdl-38130604

ABSTRACT

BACKGROUND: Varicosis is a common venous condition, which is typically treated surgically. However, selection of the optimal surgical approach can be challenging. Previous studies comparing endovenous laser treatment (EVLT) and conventional surgery were retrospective and observational in nature and the results may therefore have been influenced by selection bias and the presence of other confounding factors. In this study, we used propensity score matching to reduce selection bias when comparing EVLT and conventional surgery for the treatment of varicose great saphenous veins. AIM: To compare the perioperative and postoperative outcomes of EVLT and conventional surgery in patients with great saphenous vein varicosis. METHODS: We retrospectively reviewed the records of 1063 patients treated for primary varicosis of the great saphenous vein at the Second Affiliated Hospital of Xuzhou Medical University between January 2009 and December 2019. Among them, 56 patients were excluded owing to additional small saphenous varicose vein involvement, 81 owing to recurring varicose veins, 83 owing to complicated varicose veins (CEAP clinical classification C5-C6), and 6 owing to perioperative phlebitis. Finally, 772 patients were enrolled in this study. Standard demographic and clinicopathological data were collected from the medical records of the patients. For propensity score matching, 522 patients (261 who underwent EVLT and 261 who underwent conventional surgery) were randomly matched 1:1 by age, sex, onset time, smoking status, presence of diabetes, family history, stress therapy, C class, and the affected leg. RESULTS: Of the 772 patients included in the study, 467 underwent EVLT and 305 underwent conventional surgery. There were significant differences in age, onset time, smoking and diabetes status, and family history between the two groups. Following propensity score matching, no significant differences in patients' characteristics remained between the two groups. ELVT was associated with a shorter operation time and hospital stay than conventional surgery, both before and after propensity score matching. There were no differences in complications between the two groups after propensity score matching. Patients who underwent EVLT had a higher recurrence rate during the two-year follow-up period than those who underwent conventional surgery (33.33% vs 21.46%, χ2 = 11.506, P = 0.001), and a greater percentage of patients who underwent EVLT experienced pain one week after the procedure (39.85% vs 19.54%, P = 0.000). CONCLUSION: EVLT may not always be the best option for the treatment of great saphenous vein varicosis.

10.
Adv Sci (Weinh) ; 10(35): e2305101, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37870177

ABSTRACT

Herein, the first diversity-oriented catalytic asymmetric dearomatization of indoles with o-quinone diimides (o-QDIs) is reported. The catalytic asymmetric dearomatization (CADA) of indoles is one of the research focuses in terms of the structural and biological importance of dearomatized indole derivatives. Although great achievements have been made in target-oriented CADA reactions, diversity-oriented CADA reactions are regarded as more challenging and remain elusive due to the lack of synthons featuring multiple reaction sites and the difficulty in precise control of chemo-, regio-, and enantio-selectivity. In this work, o-QDIs are employed as a versatile building block, enabling the chemo-divergent dearomative arylation and [4 + 2] cycloaddition reactions of indoles. Under the catalysis of chiral phosphoric acid and mild conditions, various indolenines, furoindolines/pyrroloindolines, and six-membered-ring fused indolines are collectively prepared in good yields with excellent enantioselectivities. This diversity-oriented synthesis protocol enriches the o-quinone chemistry and offers new opportunities for CADA reactions.

11.
Cancer Cell Int ; 23(1): 215, 2023 Sep 26.
Article in English | MEDLINE | ID: mdl-37752544

ABSTRACT

BACKGROUND: The aim of this study was to determine the underlying potential mechanisms and function of DIO3OS, a lincRNA in osteosarcoma and clarify that DIO3OS can be used as a potential diagnostic biomarker and immunotherapeutic target. METHODS: The expression matrix data and clinical information were obtained from XENA platform of UCSC and GEO database as the test cohorts. The external validation cohort was collected from our hospital. Bioinformatics analysis was used to annotate the biological function of DIO3OS. Immune infiltration and immune checkpoint analysis were applied to evaluate whether DIO3OS can be used as an immunotherapeutic target. ROC curves and AUC were established to assess the diagnostic value of DIO3OS for differentiating patients from other subtypes sarcoma. The expression analysis was detected by qRT-PCR, western blot, and immunohistochemical. Wound healing assay and Transwell assay were applied to determine the migration and invasion function of DIO3OS in osteosarcoma cell lines. The tail vein injection osteosarcoma cells metastases model was used in this research. RESULTS: High expression of DIO3OS was identified as a risk lincRNA for predicting overall survival of osteosarcoma in test cohort. The outcomes of experiments in vitro and in vivo showed that low expression of DIO3OS limited osteosarcoma tumor metastasis with inhibiting TGF-ß signaling pathway. Immune checkpoint genes (CD200 and TNFRSF25) expressions were inhibited in the low DIO3OS expression group. The DIO3OS expression can be applied to reliably distinguish osteosarcoma from lipomatous neoplasms, myomatous neoplasms, nerve sheath tumors, and synovial-like neoplasms. This result was further validated in the validation cohort. CONCLUSIONS: In conclusion, our outcomes indicated that DIO3OS is a potential diagnostic and prognostic biomarker of osteosarcoma, emphasizing its potential as a target of immunotherapy to improve the treatment of osteosarcoma through TGF-ß signaling pathway. TRIAL REGISTRATION NUMBER: The present retrospectively study was approved by the Ethics Committee of The Second Affiliated Hospital of Nanchang University [Review (2020) No. (115)].

12.
Nat Commun ; 14(1): 5189, 2023 Aug 25.
Article in English | MEDLINE | ID: mdl-37626030

ABSTRACT

The catalytic asymmetric dearomatization (CADA) reaction has proved to be a powerful protocol for rapid assembly of valuable three-dimensional cyclic compounds from readily available planar aromatics. In contrast to the well-studied indoles and naphthols, phenols have been considered challenging substrates for intermolecular CADA reactions due to the combination of strong aromaticity and potential regioselectivity issue over the multiple nucleophilic sites (O, C2 as well as C4). Reported herein are the chiral phosphoric acid-catalyzed divergent intermolecular CADA reactions of common phenols with azoalkenes, which deliver the tetrahydroindolone and cyclohexadienone products bearing an all-carbon quaternary stereogenic center in good yields with excellent ee values. Notably, simply adjusting the reaction temperature leads to the chemo-divergent intermolecular (3 + 2) and alkylation dearomatization reactions. Moreover, the stereo-divergent synthesis of four possible stereoisomers in a kind has been achieved via changing the sequence of catalyst enantiomers.

13.
Int J Gen Med ; 16: 3491-3501, 2023.
Article in English | MEDLINE | ID: mdl-37601803

ABSTRACT

Background: Non-valvular atrial fibrillation (NVAF) is associated with increased stroke in elderly populations, yet anticoagulant therapy is underutilized. We analyzed clinical characteristics and anticoagulation treatment rates of elderly NVAF patients hospitalized in Dali, China, to identify potential contributing factors. Methods: We collected data for 155 elderly patients with NVAF aged ≥60 years, from July 01, 2020, to December 31, 2021. We analyzed the awareness rate, clinical characteristics, and anticoagulant treatment rate of atrial fibrillation (AF), and identified factors influencing treatment. Patients were followed up one year after discharge to assess vital status, cardiovascular events, and anticoagulation therapy status. Results: Among 155 patients, 52.26% were female, and the average age was 75.77 years. The awareness rate of AF was 47.74% at admission, and only 21.94% received anticoagulant therapy. After discharge, the rate of anticoagulant therapy significantly increased to 70.97%, and 89.09% used new oral anticoagulants. Thromboembolic history and persistent AF predicted anticoagulant therapy at discharge, while male gender, previous bleeding history, and antiplatelet therapy predicted non-anticoagulant therapy. Out of 133 patients who completed a one-year follow-up, 23.31% died, 3.01% had strokes, and 3.01% experienced bleeding. Anticoagulant therapy decreased to 51.96% during the follow-up year. Conclusion: Our findings highlight the low awareness rate and anticoagulant treatment rate, and high mortality among elderly NVAF patients in Dali. The development of comprehensive intervention strategies is critical to standardize AF management and improve prognosis.

14.
Inorg Chem ; 62(34): 13722-13730, 2023 Aug 28.
Article in English | MEDLINE | ID: mdl-37540079

ABSTRACT

Carbon dioxide cycloaddition into fine chemicals is prospective technology to solve energy crisis and environmental issues. However, high temperature and pressure are usually required in the conventional cycloaddition reactions of CO2 with epoxides. Moreover, metal active sites play a vital role in the CO2 cycloaddition, but it is still unclear. Herein, we select the isostructural MOF-919-Cu-Fe and MOF-919-Cu-Al as models to promote the performance and clarify the effects of metal type on the CO2 cycloaddition. The MOF-919-Cu-Fe with exposed Fe and Cu Lewis acid sites reaches the CO2 cycloaddition with over 99.9% conversion and over 99.9% selectivity at room temperature and a 1 bar CO2 atmosphere, 3.0- and 52.6-fold higher than those of the MOF-919-Cu-Al with Al and Cu sites (33.8%) and the 1H-pyrazole-4-carboxylic acid, Fe, and Cu mixed system (1.9%), respectively. The proposed mechanism demonstrated that the exposed Fe3+ sites facilitate the ring opening of epoxide and CO2 activation to boost the CO2 cycloaddition reaction. This work provides a new insight to tune the catalytic sites of MOFs to achieve high performance for CO2 fixation.

15.
Environ Sci Technol ; 57(33): 12280-12290, 2023 08 22.
Article in English | MEDLINE | ID: mdl-37549959

ABSTRACT

Arsenic (As) is a major environmental pollutant and poses a significant health risk to humans through rice consumption. Elevating the soil redox potential (Eh) has been shown to reduce As bioavailability and decrease As accumulation in rice grains. However, sustainable methods for managing the Eh of rice paddies are lacking. To address this issue, we propose a new approach that uses man-made aerenchymatous tissues (MAT) to increase soil Eh by mimicking O2 release from wet plant roots. Our study demonstrated that the MAT method sustainably increased the soil Eh levels from -119 to -80.7 mV (∼30%), over approximately 100 days and within a radius of around 5 cm from the surface of the MAT. Moreover, it resulted in a significant reduction (-28.5% to -63.3%) in dissolved organic carbon, Fe, Mn, and As concentrations. MAT-induced Fe(III) (oxyhydr)oxide minerals served as additional adsorption sites for dissolved As in soil porewater. Furthermore, MAT promoted the oxidation of arsenite to the less mobile arsenate by significantly enhancing the relative abundance of the aioA gene (130% increase in the 0-5 cm soil zone around MAT). The decrease in As bioavailability significantly reduced As accumulation in rice grains (-30.0%). This work offers a low-cost and sustainable method for mitigating As release in rice paddies by addressing the issue of soil Eh management.


Subject(s)
Arsenic , Oryza , Soil Pollutants , Humans , Iron , Soil , Oxidation-Reduction , Oxides
16.
Cureus ; 15(6): e40968, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37503480

ABSTRACT

Foreign body ingestion is a common problem among elderly patients and can pose a serious health risk, particularly for those with communication barriers, cognitive impairments, or obscure medical histories. This report presents the case of a 67-year-old female inpatient who had a language communication barrier and accidentally ingested a blister pack. Effective communication was facilitated through an interpreter, and prompt endoscopic intervention was conducted to remove the foreign body safely. The patient was discharged with no further symptoms during follow-up. This case highlights the importance of prompt evaluation and intervention for foreign body ingestion in elderly patients, particularly those with communication barriers.

17.
Chem Asian J ; 18(18): e202300591, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37524655

ABSTRACT

The success in the identification of the two enantioisomeric surfaces of electrophiles by dinuclear zinc catalysts is disclosed. This protocol realizes a dinuclear zinc-cocatalyzed desymmetrization of cyclopentendiones using α-hydroxy aryl ketones as nucleophiles through Michael addition reaction. Under mild conditions, a series of functional cyclopentanediones bearing multiple stereogenic centers including an all-carbon quaternary stereocenter, were obtained in moderate to good yields with excellent stereoselectivities.

18.
Chem Commun (Camb) ; 59(45): 6929-6932, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-37204001

ABSTRACT

The first Zn-ProPhenol catalyzed asymmetric inverse-electron-demand Diels-Alder reaction has been accomplished. This protocol was carried out by a dual-activation mode under mild conditions, allowing the preparation of various biologically important dihydropyrans in good yields with excellent stereoselectivities.

19.
Antibiotics (Basel) ; 12(4)2023 Apr 14.
Article in English | MEDLINE | ID: mdl-37107122

ABSTRACT

OBJECTIVES: Multidrug-resistant (MDR) Gram-negative bacterial infections have limited treatment options due to the impermeability of the outer membrane. New therapeutic strategies or agents are urgently needed, and combination therapies using existing antibiotics are a potentially effective means to treat these infections. In this study, we examined whether phentolamine can enhance the antibacterial activity of macrolide antibiotics against Gram-negative bacteria and investigated its mechanism of action. METHODS: Synergistic effects between phentolamine and macrolide antibiotics were evaluated by checkerboard and time-kill assays and in vivo using a Galleria mellonella infection model. We utilized a combination of biochemical tests (outer membrane permeability, ATP synthesis, ΔpH gradient measurements, and EtBr accumulation assays) with scanning electron microscopy to clarify the mechanism of phentolamine enhancement of macrolide antibacterial activity against Escherichia coli. RESULTS: In vitro tests of phentolamine combined with the macrolide antibiotics erythromycin, clarithromycin, and azithromycin indicated a synergistic action against E. coli test strains. The fractional concentration inhibitory indices (FICI) of 0.375 and 0.5 indicated a synergic effect that was consistent with kinetic time-kill assays. This synergy was also seen for Salmonella typhimurium, Klebsiella pneumoniae, and Actinobacter baumannii but not Pseudomonas aeruginosa. Similarly, a phentolamine/erythromycin combination displayed significant synergistic effects in vivo in the G. mellonella model. Phentolamine added singly to bacterial cells also resulted in direct outer membrane damage and was able to dissipate and uncouple membrane proton motive force from ATP synthesis that, resulted in enhanced cytoplasmic antibiotic accumulation via reduced efflux pump activity. CONCLUSIONS: Phentolamine potentiates macrolide antibiotic activity via reducing efflux pump activity and direct damage to the outer membrane leaflet of Gram-negative bacteria both in vitro and in vivo.

20.
Chem Commun (Camb) ; 59(39): 5902-5905, 2023 May 11.
Article in English | MEDLINE | ID: mdl-37097750

ABSTRACT

The chiral phosphoric acid-catalyzed asymmetric intermolecular formal [3+2] cycloaddition of azoalkenes with azlactones has been established. This convergent protocol leads to a facile and enantioselective de novo construction of a wide range of fully substituted 4-pyrrolin-2-ones bearing a fully substituted carbon atom in good yields and with excellent enantioselectivities (26 examples, 72-95% yields and 87-99% ee).

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