ABSTRACT
Thermal catalytic degradation of formaldehyde (HCHO) over manganese-based catalysts is garnering significant attention. In this study, both theoretical simulations and experimental methods were employed to elucidate the primary reaction pathways of HCHO on the MnO2(110) surface. Specifically, the effects of doping MnO2 with elements such as Fe, Ce, Ni, Co, and Cu on the HCHO oxidation properties were evaluated. Advanced characterization techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), and X-ray photoelectron spectroscopy (XPS), were employed to discern the physical properties and chemical states of the active components on the catalyst surface. The comprehensive oxidation pathway of HCHO on the MnO2(110) surface includes O2 adsorption and dissociation, HCHO adsorption and dehydrogenation, CO2 desorption, H2O formation and desorption, oxygen vacancy supplementation, and other elementary reactions. The pivotal rate-determining step was identified as the hydrogen migration process, characterized by an energy barrier of 234.19 kJ mol-1. Notably, HCHOO and *CHOO emerged as crucial intermediates during the reaction. Among the doped catalysts, Fe-doped MnO2 outperformed its counterparts doped with Ce, Ni, Co, and Cu. The optimal degradation rate and selectivity were achieved at a molar ratio of Fe: Mn = 0.1. The superior performance of the Fe-doped MnO2 can be ascribed to its large specific surface area, conducive pore structure for HCHO molecular transport, rich surface-adsorbed oxygen species, and a significant presence of oxygen vacancies.
Subject(s)
Manganese , Oxides , Oxides/chemistry , Manganese Compounds/chemistry , Oxygen/chemistry , Catalysis , Formaldehyde/chemistryABSTRACT
BACKGROUND: Prostatic hyperplasia is a physiological aging process in men. After transurethral resection of prostate (TURP), visceral pain is the main cause. The effective postoperative analgesia can reduce the occurrence of postoperative complications. This study mainly studied the analgesic effect of quadratus lumborum block (QLB) on TURP. METHODS: We divided 62 patients undergoing TURP into 2 groups using a random number table method (QLB 2 group and non-QLB [control] group). Patients in the QLB group underwent ultrasound-guided posterior QLB with 20âmL of 0.25% ropivacaine on each side, and those in the control group received only general anesthesia. The primary outcome for this study was the consumption analgesic pump during 0 to 24âhours. The secondary outcomes included the first pressing time of analgesic pump during 0 to 24âhours, the pain at rest and when coughing at 1, 4, 8, 12, and 24âhours post-operation as measured with a visual analogue scale for pain, length of the hospital stay, and complications (nausea and vomiting, dizziness, and abdominal distension). RESULTS: Patients in the QLB group presented less consumption, later first pressing time of analgesic pump during 0 to 24âhours after surgery lower visual analogue scale scores at 1, 4, 8, 12, and 24âhours postsurgery than those in the control group. Moreover, their mean length of hospital stay was shorter (Pâ=â.023), and they experienced less postoperative complications than the patients in the control group. CONCLUSIONS: Ultrasound-guided QLB in TURP provided a significant analgesic effect in our patients the first day after surgery. This analgesic model may improve the postoperative recovery after TURP.
Subject(s)
Abdominal Muscles , Analgesia , Nerve Block , Pain, Postoperative/prevention & control , Transurethral Resection of Prostate/adverse effects , Aged , Aged, 80 and over , Anesthetics, Local , Humans , Male , Middle Aged , Nerve Block/adverse effects , Pain, Postoperative/etiology , Prospective Studies , Ultrasonography, InterventionalABSTRACT
Two novel cyclic hexadepsipeptides, fusarihexin A (1: ) and fusarihexin B (2: ), and two known compounds, cyclo-(L-Leu-L-Leu-D-Leu-L-Leu-L-Val) (3: ) and cyclo-(L-Leu-L-Leu-D-Leu-L-Leu-L-Ile) (4: ), were isolated from the marine mangrove endophytic fungus Fusarium sp. R5. Their chemical structures were elucidated on the basis of spectroscopic data and Marfey's analysis. In an in vitro bioassay, fusarihexin A (1: ) remarkably inhibited three plant pathogenic fungi: Colletotrichum gloeosporioides (Penz.) Sacc., which causes anthracnose in many fruits and vegetables, Colletotrichum musae (Berk. and M.âA. Curtis) Arx, which causes crown rot and anthracnose in bananas, and Fusarium oxysporum Schlecht. f. sp. lycopersici (Sacc.) W.âC. Snyder et H.âN. Hansen, which causes Fusarium wilt and fruit rot in tomatoes. Fusarihexin B (2: ) strongly inhibited C. gloeosporioides and C. musae. The compounds were more potent than carbendazim, which is widely used as an agricultural and horticultural fungicide worldwide.
Subject(s)
Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Depsipeptides/chemistry , Depsipeptides/pharmacology , Fusarium/chemistry , Peptides, Cyclic/chemistry , Drug Evaluation, Preclinical/methods , Endophytes/chemistry , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Molecular Structure , Peptides, Cyclic/isolation & purification , Peptides, Cyclic/pharmacology , Plant Roots/microbiology , WetlandsABSTRACT
A new chaetoglobosin, penochalasin K (1) bearing an unusual six-cyclic 6/5/6/5/6/13 fused ring system, along with the known analogues, chaetoglobosin C (2), penochalasin I (3), and chaetoglobosin A (4) were isolated from the solid culture of the mangrove endophytic fungus Penicillium chrysogenum V11. Their structures were elucidated by 1D, 2D NMR spectroscopic analysis and high resolution mass spectroscopic data. The absolute configuration of compound 1 was determined by comparing the theoretical and experimental electronic circular dichroism curves. Compound 1 displayed significant inhibitory activities against Colletotrichum gloeosporioides and Rhizoctonia solani (MICs=6.13, 12.26µM, respectively), which was better than those of carbendazim, and exhibited potent cytotoxicity against MDA-MB-435, SGC-7901 and A549 cells (IC50<10µM). An effective biomimetic transformation of chaetoglobosin C (2)/chaetoglobosin A (4) into penochalasin K (1)/penochalasin I (3) was developed, which provided a simple method for the semi-synthesis of chaetoglobosins with a six-cyclic 6/5/6/5/6/13 fused system formed by the connectivity of C-5 and C-2' from their corresponding epoxide analogues.
Subject(s)
Indole Alkaloids/chemistry , Penicillium chrysogenum/chemistry , Antifungal Agents/chemistry , Antifungal Agents/isolation & purification , Cell Line, Tumor , Colletotrichum/drug effects , Endophytes/chemistry , Humans , Indole Alkaloids/isolation & purification , Microbial Sensitivity Tests , Molecular Structure , Rhizoctonia/drug effectsABSTRACT
Two new coumarin derivatives, 4,4'-dimethoxy-5,5'-dimethyl-7,7'-oxydicoumarin (1), 7-(γ,γ-dimethylallyloxy)-5-methoxy-4-methylcoumarin (2), a new chromone derivative, (S)-5-hydroxy-2,6-dimethyl-4H-furo[3,4-g]benzopyran-4,8(6H)-dione (5), and a new sterone derivative, 24-hydroxylergosta-4,6,8(14),22-tetraen-3-one (6), along with two known bicoumarins, kotanin (3) and orlandin (4), were isolated from an endophytic fungus Aspergillusclavatus (collection No. R7), isolated from the root of Myoporum bontioides collected from Leizhou Peninsula, China. Their structures were elucidated using 1D- and 2D- NMR spectroscopy, and HRESIMS. The absolute configuration of compound 5 was determined by comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. Compound 6 significantly inhibited the plant pathogenic fungi Fusarium oxysporum, Colletotrichum musae and Penicillium italicum, compound 5 significantly inhibited Colletotrichum musae, and compounds 1, 3 and 4 greatly inhibited Fusarium oxysporum, showing the antifungal activities higher than those of the positive control, triadimefon.
Subject(s)
Antifungal Agents/pharmacology , Aspergillus/drug effects , Coumarins/pharmacology , Antifungal Agents/chemistry , Coumarins/chemistry , Humans , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Molecular Structure , Phytotherapy , Plant Roots/microbiology , WetlandsABSTRACT
Chinese medicines (CMs) are increasingly being used for the treatment of tumors because of their unique advantages. The induction of tumor cell apoptosis is an important method of tumor treatment. Caspase-3 is a member of the caspase (cysteine aspartic proteinases) family of enzymes, which are the major inducers of apoptosis. Caspase-3 activity is often measured in the context of research into anti-tumor drugs that target apoptosis. Many studies have shown that CMs upregulate the expression of caspase-3 in tumor cells via extrinsic and/or intrinsic pathways, removing endogenous suppression of apoptosis and promoting tumor cell death. Therefore, several CMs fulfill the criteria for anti-tumor drugs. In this paper, we review the efficacy of 14 Chinese herbal medicines, across a wide range applications, and discuss their effects on caspase-3 activity in tumor cells.