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1.
J Cancer ; 15(11): 3539-3546, 2024.
Article in English | MEDLINE | ID: mdl-38817880

ABSTRACT

Background: The primary aim of this phase II clinical study was to assess the safety and efficacy of combining anlotinib, etoposide, and platinum-based drugs as a first-line treatment for ES-SCLC. Methods: Patients underwent the standard chemotherapeutic regimen, consisting of four courses of etoposide plus cisplatin/carboplatin. Additionally, each patient received a 2-week intervention with anlotinib (12 mg/day, once daily). Anlotinib was continued until disease progression, occurrence of unbearable adverse events (AEs), or withdrawal from the research. Progression-free survival (PFS) served as the primary prognostic measure. Secondary measures included the disease control rate (DCR), objective response rate (ORR), overall survival time (OS), and the incidence of AEs. Results: The DCR and ORR were 97.6% and 91.0%, respectively. Estimated PFS and OS were 5.0 months (95% CI: 1.0-10.8 months) and 13.0 months (95% CI: 8.4-18.6 months), respectively. No unexpected adverse effects were reported during the trial. The most common adverse reactions included anemia (42.22%), hypertension (53.33%), alopecia (40.00%), elevated transaminase (24.40%), and elevated alkaline phosphatase (24.44%). Sixteen cases (35.56%) were classified as AEs of grades 3-5. No deaths attributed to treatment-related causes occurred in any patient during the trial. Conclusion: Combination chemotherapy is currently the first-line therapy for extensive small-cell lung cancer (ES-SCLC). Combining anlotinib with conventional platinum-based chemotherapy demonstrated promising therapeutic outcomes and prognosis in the management of ES-SCLC.

2.
PhytoKeys ; 242: 1-8, 2024.
Article in English | MEDLINE | ID: mdl-38764934

ABSTRACT

In this study, we describe and illustrate a new species, Primulaweiliei L.S.Yang, Z.K.Wu & G.W.Hu, from the Shennongjia Forestry District, Hubei Province in Central China. It is morphologically assigned to Primulasect.Aleuritia based on its dwarf and hairless habit, long petiole, fruits longer than calyx and covered by farina on the scape. This new species is similar to P.gemmifera and P.munroisubsp.yargongensis in the same section, but it can be distinguished by its smaller calyxes, homostylous flowers, corolla tube throat without annular appendage and only 1-2 flowers in each inflorescence. Based on the assessment conducted according to the IUCN Red List criteria, we propose that P.weiliei be classified as a Critically Endangered (CR) species.

3.
J Med Chem ; 67(10): 8099-8121, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38722799

ABSTRACT

Nicotinamide phosphoribosyltransferase (NAMPT) is an attractive therapeutic target for treating select cancers. There are two forms of NAMPT: intracellular NAMPT (iNAMPT, the rate-limiting enzyme in the mammalian NAD+ main synthetic pathway) and extracellular NAMPT (eNAMPT, a cytokine with protumorigenic function). Reported NAMPT inhibitors only inhibit iNAMPT and show potent activities in preclinical studies. Unfortunately, they failed to show efficacy due to futility and toxicity. We developed a series of FK866-based NAMPT-targeting PROTACs and identified LYP-8 as a potent and effective NAMPT degrader that simultaneously diminished iNAMPT and eNAMPT. Importantly, LYP-8 demonstrated superior efficacy and safety in mice when compared to the clinical candidate, FK866. This study highlights the importance and feasibility of applying PROTACs as a superior strategy for interfering with both the enzymatic function of NAMPT (iNAMPT) and nonenzymatic function of NAMPT (eNAMPT), which is difficult to achieve with conventional NAMPT inhibitors.


Subject(s)
Acrylamides , Drug Design , Nicotinamide Phosphoribosyltransferase , Piperidines , Nicotinamide Phosphoribosyltransferase/antagonists & inhibitors , Nicotinamide Phosphoribosyltransferase/metabolism , Acrylamides/pharmacology , Acrylamides/chemistry , Acrylamides/chemical synthesis , Animals , Humans , Piperidines/pharmacology , Piperidines/chemistry , Mice , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Cytokines/metabolism , Cell Line, Tumor , Structure-Activity Relationship , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry
4.
Biomater Sci ; 2024 May 14.
Article in English | MEDLINE | ID: mdl-38742916

ABSTRACT

The tumor immunosuppressive microenvironment (TIME) and uncontrollable release of antigens can lower the efficacy of nanovaccine-based immunotherapy (NBI). Therefore, it is necessary to develop a new strategy for TIME reshaping and controllable release of antigens to improve the NBI efficacy. Herein, an acidity-responsive Schiff base-conjugated polyphenol-coordinated nanovaccine was constructed for the first time to realize bidirectional TIME reshaping and controllable release of antigens for activating T cells. In particular, an acidity-responsive tannic acid-ovalbumin (TA-OVA) nanoconjugate was prepared via a Schiff base reaction. FeIII was coordinated with TA-OVA to produce a FeIII-TA-OVA nanosystem, and 1-methyltryptophan (1-MT) as an indoleamine 2,3-dioxygenase inhibitor was loaded to form a polyphenol-coordinated nanovaccine. The coordination between FeIII and TA could cause photothermal ablation of primary tumors, and the acidity-triggered Schiff base dissociation of TA-OVA could controllably release OVA to realize lysosome escape, initiating the body's immune response. More importantly, oxidative stress generated by a tumor-specific Fenton reaction of Fe ions could promote the polarization of tumor-associated macrophages from the M2 to M1 phenotype, resulting in the upregulation of cytotoxic T cells and helper T cells. Meanwhile, 1-MT could downregulate immunosuppressive regulatory T cells. Overall, such skillful combination of bidirectional TIME reshaping and controllable antigen release into one coordination nanosystem could effectively enhance the NBI efficacy of tumors.

5.
ACS Pharmacol Transl Sci ; 7(5): 1485-1506, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38751627

ABSTRACT

Secondary mutations in Fms-like tyrosine kinase 3-tyrosine kinase domain (FLT3-TKD) (e.g., D835Y and F691L) have become a major on-target resistance mechanism of FLT3 inhibitors, which present a significant clinical challenge. To date, no effective drugs have been approved to simultaneously overcome clinical resistance caused by these two mutants. Thus, a series of pyrazinamide macrocyclic compounds were first designed and evaluated to overcome the secondary mutations of FLT3. The representative 8v exhibited potent inhibitory activities against FLT3D835Y and FLT3D835Y/F691L with IC50 values of 1.5 and 9.7 nM, respectively. 8v also strongly suppressed the proliferation against Ba/F3 cells transfected with FLT3-ITD, FLT3-ITD-D835Y, FLT3-ITD-F691L, FLT3-ITD-D835Y-F691L, and MV4-11 acute myeloid leukemia (AML) cell lines with IC50 values of 12.2, 10.5, 24.6, 16.9, and 6.8 nM, respectively. Furthermore, 8v demonstrated ideal anticancer efficacy in a Ba/F3-FLT3-ITD-D835Y xenograft model. The results suggested that 8v can serve as a promising macrocycle-based FLT3 inhibitor for the treatment of AML.

7.
Org Lett ; 2024 May 27.
Article in English | MEDLINE | ID: mdl-38802298

ABSTRACT

To realize strong donor-acceptor face-to-face stacking for efficient through-space charge transfer-type thermally activated delayed fluorescence, a conceptually new design strategy is proposed to couple flexible bridges with adequate rigidity via built-in intramolecular hydrogen bonds (IHBs). The resulting emitter ACE-CN has a planarized benzyl methyl ether bridge self-anchored by the C-H···O IHB and shows a high photoluminescence quantum efficiency of 93%. The solution- and vacuum-processed devices exhibited high external quantum efficiencies of 11.8% and 24.7%, respectively.

8.
Org Lett ; 2024 May 24.
Article in English | MEDLINE | ID: mdl-38787765

ABSTRACT

Picrachinentins A-F (1-6, respectively), six novel cyclopeptide alkaloid-type burpitides (CPABs), were isolated and fully elucidated from the EtOH extract of the stems and leaves of Picrasma chinensis. Structurally, compounds 1-6 have a 14-membered paracyclophane ring system that was closed through an ether bond between the ß-hydroxy amino acid and tyrosine and modified with a 4,5-methylenedioxybenzoyloxy (MDBz, 3 and 5) or hexanoyl (Hexa, 1, 2, 4, and 6) group at the N-terminus. Interestingly, this is the first report on the isolation and characterization of CPABs from plants of the Simaroubaceae family. In addition, all compounds showed a neuroprotective effect against H2O2-damaged SH-SY5Y cells. Compound 1 was further investigated for its neuroprotective activities using a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease animal model, and it dramatically improved MPTP-impaired motor behavioral performance. Biochemical analysis revealed compound 1 restored the tyrosine hydroxylase expression in the striatum of the MPTP-damaged mouse brain, which demonstrates its protective effect on dopaminergic neurons.

9.
Phytochemistry ; 224: 114140, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38750709

ABSTRACT

Eight previously undescribed cevanine-type steroidal alkaloids, cirrhosinones I-N and cirrhosinols A-B, along with five known analogs, were isolated from the bulbs of Fritillaria cirrhosa D. Don. Their structures were elucidated on the basis of comprehensive analysis of HRESIMS, 1D and 2D NMR spectroscopic data, and single-crystal X-ray diffraction analyses. All compounds revealed weak NO inhibitory activities in the LPS-stimulated NR8383 cells at the concentration of 20 µM, with inhibition ratios ranging from 5.1% to 14.3%.

10.
BMC Health Serv Res ; 24(1): 638, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38760746

ABSTRACT

OBJECTIVE: To assess the influence of supply and demand factors on the contract behavior of occupational populations with general practitioner (GP) teams. METHODS: We employed a system dynamics approach to assess and predict the effect of the general practitioner service package (GPSP) and complementary incentive policies on the contract rate for 2015-2030. First, the GPSP is designed to address the unique needs of occupational populations, enhancing the attractiveness of GP contracting services, including three personalized service contents tailored to demand-side considerations: work-related disease prevention (WDP), health education & counseling (HEC), and health-care service (HCS). Second, the complementary incentive policies on the supply-side included income incentives (II), job title promotion (JTP), and education & training (ET). Considering the team collaboration, the income distribution ratio (IDR) was also incorporated into supply-side factors. FINDINGS: The contract rate is predicted to increase to 57.8% by 2030 after the GPSP intervention, representing a 15.4% increase on the non-intervention scenario. WDP and HEC have a slightly higher (by 2%) impact on the contract rate than that from HCS. Regarding the supply-side policies, II have a more significant impact on the contract rate than JTP and ET by 3-5%. The maximum predicted contract rate of 75.2% is expected by 2030 when the IDR is 0.5, i.e., the GP receives 50% of the contract income and other members share 50%. CONCLUSION: The GP service package favorably increased the contract rate among occupational population, particularly after integrating the incentive policies. Specifically, for a given demand level, the targeted content of the package enhanced the attractiveness of contract services. On the supply side, the incentive policies boost GPs' motivation, and the income distribution motivated other team members.


Subject(s)
General Practitioners , Humans , Contract Services , General Practice
11.
Research (Wash D C) ; 7: 0359, 2024.
Article in English | MEDLINE | ID: mdl-38694199

ABSTRACT

Porous substrates act as open "interfacial reactors" during the synthesis of polyamide composite membranes via interfacial polymerization. However, achieving a thin and dense polyamide nanofilm with high permeance and selectivity is challenging when using a conventional substrate with uniform wettability. To overcome this limitation, we propose the use of Janus porous substrates as confined interfacial reactors to decouple the local monomer concentration from the total monomer amount during interfacial polymerization. By manipulating the location of the hydrophilic/hydrophobic interface in a Janus porous substrate, we can precisely control the monomer solution confined within the hydrophilic layer without compromising its concentration. The hydrophilic surface ensures the uniform distribution of monomers, preventing the formation of defects. By employing Janus substrates fabricated through single-sided deposition of polydopamine/polyethyleneimine, we significantly reduce the thickness of the polyamide nanofilms from 88.4 to 3.8 nm by decreasing the thickness of the hydrophilic layer. This reduction leads to a remarkable enhancement in water permeance from 7.2 to 52.0 l/m2·h·bar while still maintaining ~96% Na2SO4 rejection. The overall performance of this membrane surpasses that of most reported membranes, including state-of-the-art commercial products. The presented strategy is both simple and effective, bringing ultrapermeable polyamide nanofilms one step closer to practical separation applications.

12.
Eur J Med Chem ; 272: 116478, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38718624

ABSTRACT

Metallodrugs exhibiting distinct mechanisms of action compared with cisplatin hold promise for overcoming cisplatin resistance and improving the efficacy of anticancer drugs. In this study, a new series of rhodium (Rh)(III) complexes containing tris(triphenylphosphine)rhodium(I) chloride [(TPP)3RhCl] (TPP = triphenylphosphine, TPP=O = triphenylphosphine oxide) and 8-hydroxyquinoline derivatives (H-XR1-H-XR4), namely [Rh(XR1)2(TPP)Cl]·(TPP=O) (Yulin Normal University-1a [YNU-1a]), [Rh(XR2)2(TPP)Cl] (YNU-1b), [Rh(XR3)2(TPP)Cl] (YNU-1c), and [Rh(XR4)2(TPP)Cl] (YNU-1d), was synthesized and characterized via X-ray diffraction, mass spectrometry and IR. The cytotoxicity of the compounds YNU-1a-YNU-1d in Hep-G2 and HCC1806 human cancer cell lines and normal HL-7702 cell line was evaluated. YNU-1c exhibited cytotoxicity and selectivity in HCC1806 cells (IC50 = 0.13 ± 0.06 µM, selectivity factor (SF) = 384.6). The compounds YNU-1b and YNU-1c, which were selected for mechanistic studies, induced the activation of apoptotic pathways and mitophagy. In addition, these compounds released cytochrome c, cleaved caspase-3/pro-caspase-3 and downregulated the levels of mitochondrial respiratory chain complexes I/IV (M1 and M4) and ATP. The compound YNU-1c, which was selected for in vivo experiments, exhibited tumor growth inhibition (58.9 %). Importantly, hematoxylin and eosin staining and TUNEL revealed that HCC1806 tumor tissues exhibited significant apoptotic characteristics. YNU-1a-YNU-1d compounds are promising drug candidates that can be used to overcome cisplatin resistance.


Subject(s)
Antineoplastic Agents , Cell Proliferation , Coordination Complexes , Drug Screening Assays, Antitumor , Mitophagy , Oxyquinoline , Rhodium , Humans , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Rhodium/chemistry , Rhodium/pharmacology , Oxyquinoline/chemistry , Oxyquinoline/pharmacology , Oxyquinoline/chemical synthesis , Coordination Complexes/pharmacology , Coordination Complexes/chemistry , Coordination Complexes/chemical synthesis , Animals , Structure-Activity Relationship , Cell Proliferation/drug effects , Mitophagy/drug effects , Molecular Structure , Organophosphorus Compounds/pharmacology , Organophosphorus Compounds/chemistry , Organophosphorus Compounds/chemical synthesis , Dose-Response Relationship, Drug , Apoptosis/drug effects , Mice , Cell Line, Tumor
13.
J Org Chem ; 89(8): 5905-5910, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38579179

ABSTRACT

The total syntheses of (±)-quebrachamine and (±)-kopsiyunnanine D are reported. Key transformations include an intermolecular Horner-Wadsworth-Emmons olefination to merge the two fragments convergently and an intramolecular Mitsunobu reaction to introduce the synthetically challenging nine-membered azonane ring efficiently.

14.
Environ Res ; 252(Pt 2): 118937, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38621627

ABSTRACT

Hydroxyapatite, a calcium phosphate biomass material known for its excellent biocompatibility, holds promising applications in water, soil, and air treatment. Sodium alginate/hydroxyapatite/chitosan (SA-HA-CS) microspheres were synthesized by cross-linking sodium alginate with calcium chloride. These microspheres were carriers for immobilizing extracellular crude enzymes from white rot fungi through adsorption, facilitating the degradation of 2,4,6-trichlorophenol (2,4,6-TCP) in water and soil. At 50 °C, the immobilized enzyme retained 87.2% of its maximum activity, while the free enzyme activity dropped to 68.86%. Furthermore, the immobilized enzyme maintained 68.09% of its maximum activity at pH 7, surpassing the 51.16% observed for the free enzyme. Under optimal conditions (pH 5, 24 h), the immobilized enzymes demonstrated a remarkable 94.7% removal rate for 160 mg/L 2,4,6-TCP, outperforming the 62.1% achieved by free crude enzymes. The degradation of 2,4,6-TCP by immobilized and free enzymes adhered to quasi-first-order degradation kinetics. Based on LC-MS, the plausible biodegradation mechanism and reaction pathway of 2,4,6-TCP were proposed, with the primary degradation product identified as 1,2,4-trihydroxybenzene. The immobilized enzyme effectively removed 72.9% of 2,4,6-TCP from the soil within 24 h. The degradation efficiency of the immobilized enzyme varied among different soil types, exhibiting a negative correlation with soil organic matter content. These findings offer valuable insights for advancing the application of immobilized extracellular crude enzymes in 2,4,6-TCP remediation.

15.
Adv Mater ; : e2400075, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38597782

ABSTRACT

Designing nanocomposite hydrogels with oriented nanosheets has emerged as a promising toolkit to achieve preferential performances that go beyond their disordered counterparts. Although current fabrication strategies via electric/magnetic force fields have made remarkable achievements, they necessitate special properties of nanosheets and suffer from an inferior orientation degree of nanosheets. Herein, a facile and universal approach is discovered to elaborate MXene-based nanocomposite hydrogels with highly oriented, heterogeneous architecture by virtue of supergravity to replace conventional force fields. The key to such architecture is to leverage bidirectional, force-tunable attributes of supergravity containing coupled orthogonal shear and centrifugal force field for steering high-efficient movement, pre-orientation, and stacking of MXene nanosheets in the bottom. Such a synergetic effect allows for yielding heterogeneous nanocomposite hydrogels with a high-orientation MXene-rich layer (orientation degree, f = 0.83) and a polymer-rich layer. The authors demonstrate that MXene-based nanocomposite hydrogels leverage their high-orientation, heterogeneous architecture to deliver an extraordinary electromagnetic interference shielding effectiveness of 55.2 dB at 12.4 GHz yet using a super-low MXene of 0.3 wt%, surpassing most hydrogels-based electromagnetic shielding materials. This versatile supergravity-steered strategy can be further extended to arbitrary nanosheets including MoS2, GO, and C3N4, offering a paradigm in the development of oriented nanocomposites.

16.
Cell Death Dis ; 15(4): 241, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38561375

ABSTRACT

Soft-tissue sarcomas (STS) emerges as formidable challenges in clinics due to the complex genetic heterogeneity, high rates of local recurrence and metastasis. Exploring specific targets and biomarkers would benefit the prognosis and treatment of STS. Here, we identified RCC1, a guanine-nucleotide exchange factor for Ran, as an oncogene and a potential intervention target in STS. Bioinformatics analysis indicated that RCC1 is highly expressed and correlated with poor prognosis in STS. Functional studies showed that RCC1 knockdown significantly inhibited the cell cycle transition, proliferation and migration of STS cells in vitro, and the growth of STS xenografts in mice. Mechanistically, we identified Skp2 as a downstream target of RCC1 in STS. Loss of RCC1 substantially diminished Skp2 abundance by compromising its protein stability, resulting in the upregulation of p27Kip1 and G1/S transition arrest. Specifically, RCC1 might facilitate the nucleo-cytoplasmic trafficking of Skp2 via direct interaction. As a result, the cytoplasmic retention of Skp2 would further protect it from ubiquitination and degradation. Notably, recovery of Skp2 expression largely reversed the phenotypes induced by RCC1 knockdown in STS cells. Collectively, this study unveils a novel RCC1-Skp2-p27Kip1 axis in STS oncogenesis, which holds promise for improving prognosis and treatment of this formidable malignancy.


Subject(s)
Sarcoma , Animals , Humans , Mice , Cell Cycle , Cell Cycle Proteins/metabolism , Cyclin-Dependent Kinase Inhibitor p27/genetics , Cyclin-Dependent Kinase Inhibitor p27/metabolism , Guanine Nucleotide Exchange Factors/genetics , Guanine Nucleotide Exchange Factors/metabolism , Nuclear Proteins/metabolism , S-Phase Kinase-Associated Proteins/genetics , S-Phase Kinase-Associated Proteins/metabolism , Sarcoma/genetics , Sarcoma/pathology , Ubiquitination , Up-Regulation
17.
PLoS One ; 19(4): e0300705, 2024.
Article in English | MEDLINE | ID: mdl-38603672

ABSTRACT

Obesity is a major independent risk factor for chronic kidney disease and can activate renal oxidative stress injury. Ascorbate and aldarate metabolism is an important carbohydrate metabolic pathway that protects cells from oxidative damage. However the effect of oxidative stress on this pathway is still unclear. Therefore, the primary objective of this study was to investigate the ascorbate and aldarate metabolism pathway in the kidneys of high-fat diet-fed obese mice and determine the effects of oxidative stress. Male C57BL/6J mice were fed on a high-fat diet for 12 weeks to induce obesity. Subsequently, non-targeted metabolomics profiling was used to identify metabolites in the kidney tissues of the obese mice, followed by RNA sequencing using transcriptomic methods. The integrated analysis of metabolomics and transcriptomics revealed the alterations in the ascorbate and aldarate metabolic pathway in the kidneys of these high-fat diet-fed obese mice. The high-fat diet-induced obesity resulted in notable changes, including thinning of the glomerular basement membrane, alterations in podocyte morphology, and an increase in oxidative stress. Metabolomics analysis revealed 649 metabolites in the positive-ion mode, and 470 metabolites in the negative-ion mode. Additionally, 659 differentially expressed genes (DEGs) were identified in the obese mice, of which 34 were upregulated and 625 downregulated. Integrated metabolomics and transcriptomics analyses revealed two DEGs and 13 differential metabolites in the ascorbate and aldarate metabolic pathway. The expression levels of ugt1a9 and ugt2b1 were downregulated, and the ascorbate level in kidney tissue of obese mice was reduced. Thus, renal oxidative stress injury induced by high-fat diet affects metabolic regulation of ascorbate and aldarate metabolism in obese mice. Ascorbate emerged as a potential marker for predicting kidney damage due to high-fat diet-induced obesity.


Subject(s)
Diet, High-Fat , Kidney , Animals , Mice , Male , Diet, High-Fat/adverse effects , Mice, Obese , Mice, Inbred C57BL , Kidney/metabolism , Obesity/etiology , Obesity/metabolism , Metabolomics , Gene Expression Profiling
18.
Phytochemistry ; 223: 114106, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38657885

ABSTRACT

Daphmacrimines A-K (1-11) were isolated from the leaves and stems of Daphniphyllum macropodum Miq. Their structures and stereochemistries were determined by extensive techniques, including HRESIMS, NMR, ECD, IR, and single-crystal X-ray crystallography. Daphmacrimines A-D (1-4) are unprecedented Daphniphyllum alkaloids with a 2-oxazolidinone ring. Daphmacrimine I (9) contains a nitrile group, which is relatively rare in naturally occurring alkaloids. The abilities of daphmacrimines A-D and daphmacrimines G-K to enhance lysosomal biogenesis were evaluated through LysoTracker Red staining. Daphmacrimine K (11) can induce lysosomal biogenesis and promote autophagic flux.


Subject(s)
Alkaloids , Daphniphyllum , Alkaloids/chemistry , Alkaloids/isolation & purification , Alkaloids/pharmacology , Molecular Structure , Daphniphyllum/chemistry , Plant Leaves/chemistry , Humans , Crystallography, X-Ray , Lysosomes/drug effects , Lysosomes/metabolism , Plant Stems/chemistry , Molecular Conformation
19.
Bull Environ Contam Toxicol ; 112(5): 70, 2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38676752

ABSTRACT

Trichloroethylene (TCE) poses a potentially toxic threat to humans and the environment and widely exists in contaminated sites. White rot fungi effectively degrade refractory pollutants, while a few research studies use white rot fungi to degrade TCE. In this study, we investigated TCE biodegradation by white rot fungi and the potential influencing factors in the environment and attempted to research the effect of TCE on the physiological characteristics of white rot fungi. White rot fungi (Trametes versicolor, Pseudotrametes gibbosa, Pycnoporus sanguines and Pleurotus ostreatus) were added to the liquid medium for shock culture. The results revealed that T. versicolor exhibited the most pronounced efficacy in removing TCE, with a degradation rate of 81.10% within a 7 d period. TCE induces and is degraded by cytochrome P450 enzymes. High pH and Cr(VI) adversely affected the effectiveness of the biodegradation of TCE, but the salinity range of 0-1% had less effect on biodegradation. Overall, the effectiveness of degradation of TCE by T. versicolor has been demonstrated, and it provides a reference for the application prospects of white rot fungi in TCE-contaminated soils.


Subject(s)
Biodegradation, Environmental , Trichloroethylene , Trichloroethylene/metabolism , Soil Pollutants/metabolism , Soil Pollutants/toxicity , Polyporaceae/metabolism
20.
Water Res ; 256: 121551, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38581981

ABSTRACT

Many antibiotic disinfection byproducts have been detected but their toxicity has not been evaluated adequately. In this report, the chlorination reaction kinetics of five common sulfamides (SAs), reaction intermediates and their toxicity were investigated. Chlorination of sulfapyridine (SPD), sulfamethazine (SMT), sulfathiazole (STZ), and sulfisoxazole (SIZ) followed the second-order kinetics, and were degraded completely within 10 min. A large number of reaction intermediates were deteced by LC-MS, among which a total of 16 intermediates were detected for the first time. Toxicity of the five SAs chlorination solutions was evaluated separately by examining their effects on the growth rate of S. salivarius K12, a commensal bacterium in the human digestive system. After 30 min chlorination, solutions of SMT, STZ and sulfadiazine (SDZ) each exhibited severe toxicity by inhibiting the bacteria growth completely, whereas the inhibition was only 50 % and 20  % by SIZ and SPD respectively. Based on the comparison between toxicity test results and mass spectra, three SA chlorination intermediates, m/z 187.2 (C10H10N4), m/z 287.2 (C9H7N3O4S2) and m/z 215 (C7H10N4O2S/C12H14N4) were proposed to be the primary toxicants in the chlorination products. Our study demonstrated the power of combined approach of chemical analysis and toxicity testing in identifying toxic disinfection byproducts, and highlighted the ne ed for more research on the toxicity evaluation and risk assessment of antibiotic disinfection byproducts.


Subject(s)
Disinfection , Sulfonamides , Humans , Sulfonamides/toxicity , Halogenation , Bacteria/drug effects , Disinfectants/toxicity , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/toxicity , Anti-Bacterial Agents/chemistry , Water Pollutants, Chemical/toxicity , Water Pollutants, Chemical/chemistry
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