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1.
Huan Jing Ke Xue ; 45(2): 1150-1160, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471952

RESUMO

In order to evaluate the feasibility of using Burkholderia sp. Y4 as a cadmium (Cd)-reducing bacterial agent in contaminated wheat fields, the changes in the rhizosphere soil microbial community and Cd available state, as well as the content and transport characteristics of Cd in the wheat root, basal node, internode, and grain under the treatment of strain Y4 were tested using microbial high-throughput sequencing, step-by-step extraction, subcellular distribution, and occurrence analyses. The results showed that root application of strain Y4 significantly reduced the root and grain Cd content of wheat by 7.7% and 30.3%, respectively, compared with that in the control treatment. The Cd content and Cd transfer factor results in wheat vegetative organs showed that strain Y4 reduced the Cd transfer factor from basal node to internode by 79.3%, and Cd content in the wheat internode stem also decreased by 50.9%. The study of Cd occurrence morphology showed that strain Y4 treatment increased the proportion of residual Cd in roots and basal ganglia, decreased the contents of inorganic and water-soluble Cd in roots, and increased the content of residual Cd in basal ganglia. Further examination of the subcellular distribution of Cd showed that the Cd content in root cell walls and basal ganglia cell fluid increased by 21.3% and 98.2%, respectively, indicating that the Cd fixation ability of root cell walls and basal ganglia cell fluid was improved by the strain Y4 treatment. In the rhizosphere soil, it was found that the microbial community structure was changed by strain Y4 application. Under the Y4 treatment, the relative abundance of Burkholderia increased from 9.6% to 11.5%, whereas that of Acidobacteriota decreased. Additionally, the relative abundance of Gemmatimonadales, Pseudomonadales, and Chitinophagales were also increased by strain Y4 treatment. At the same time, the application of strain Y4 increased the pH value of rhizosphere soil by 8.3%. The contents of exchangeable Cd, carbonate-bound Cd, and iron-manganese oxide-bound Cd in the soil decreased by 44.4%, 21.7%, and 15.9%, respectively, whereas the proportion of residual Cd reached 53.6%. Root application of strain Y4 increased the contents of nitrate nitrogen and ammonium nitrogen in the soil by 22.0% and 21.4%, respectively, and the contents of alkaline nitrogen also increased to a certain extent. In conclusion, the root application of strain Y4 not only improved soil nitrogen availability but also inhibited Cd transport and accumulation from contaminated soil to wheat grains in a "two-stage" manner by reducing Cd availability in rhizosphere soil and improving Cd interception and fixation capacity of wheat roots and basal nodes. Therefore, Burkholderia Y4 has application potential as a Cd-reducing and growth-promoting agent in wheat.


Assuntos
Burkholderia , Compostos Férricos , Poluentes do Solo , Cádmio/análise , Triticum , Burkholderia/fisiologia , Fator de Transferência , Solo/química , Nitrogênio/análise , Poluentes do Solo/análise
2.
Huan Jing Ke Xue ; 45(2): 1185-1195, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471955

RESUMO

Microplastics are an emerging contaminant that can persist in the environment for extended periods, posing risks to ecological systems. Recently, microplastic pollution has emerged as a major global environmental problem. In order to ensure accurate and scientific evaluation of the ecological risks associated with microplastic pollution, it is of paramount importance to improve the simplicity and reliability of microplastic identification, systematically analyze the pollution characteristics of microplastics in various environmental media, and clarify their environmental impacts. Machine learning technology has gained widespread attention in microplastic research by learning and analyzing large volumes of data to establish result evaluation or prediction models. The use of machine learning can enhance the automation and identification efficiency of visual and spectral identification of microplastics, provide scientific support for tracing the sources of microplastic pollution, and help reveal the complex environmental effects of microplastics. This review provides a summary of the application characteristics and limitations of machine learning in the aforementioned areas by reviewing the progress made in research that employs machine learning technology in microplastic identification and environmental risk assessment. Furthermore, the findings of the review will provide suggestions and prospects for the development and application of machine learning in related areas.

3.
Biochim Biophys Acta Mol Basis Dis ; 1870(4): 167106, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428685

RESUMO

Bladder cancer (BLCA) is one of the most prevalent malignancies worldwide with a high mortality rate and poor response to immunotherapy in patients expressing lower programmed death ligand 1 (PD-L1) levels. Nicotinamide phosphoribosyltransferase (NAMPT), a rate-limiting enzyme responsible for the biosynthesis of nicotinamide adenine dinucleotide (NAD+) from nicotinamide was reported to be overexpressed in various cancers; however, the role of NAMPT in BLCA is obscure. Immunohistochemistry of tissue microarrays, a real-time polymerase chain reaction, Western blotting, proliferation assay, NAD+ quantification, transwell-migration assay, and colony-formation assay were performed to measure NAMPT and PD-L1 expression levels in patients and the effect of NAMPT inhibition on T24 cells. Our study revealed that NAMPT expression was upregulated in BLCA patients with different grades and associated with poor T-cell infiltration. Notably, FK866-mediated NAMPT inhibition decreased cell viability by depleting NAD+, and reducing the migration ability and colony-formation ability of T24 cells. Interestingly, NAMPT negatively regulated PD-L1 under an interferon (IFN)-γ-mediated microenvironment. However, exogenous NAMPT activator has no effect on PD-L1. NAD+ supplementation also only increased PD-L1 in the absence of IFN-γ. Conclusively, NAMPT is crucial for BLCA tumorigenic properties, and it regulates expression of the PD-L1 immune checkpoint protein. NAMPT could be considered a target for modulating sensitivity to immunotherapy.


Assuntos
NAD , Neoplasias da Bexiga Urinária , Humanos , NAD/metabolismo , Antígeno B7-H1/genética , Nicotinamida Fosforribosiltransferase/metabolismo , Neoplasias da Bexiga Urinária/tratamento farmacológico , Microambiente Tumoral
4.
Chem Biol Drug Des ; 103(3): e14501, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38453253

RESUMO

The toxic effects of nanoparticles-silver oxide (Ag2 O) limited its use. However, loading Ag2 O nanoparticles into titanium dioxide (TiO2 ) nanotubes (Ag2 O-TiO2 -NTs) has more efficient biological activity and safety. The aim of this study was to observe the effect of Ag2 O-TiO2 -NTs on osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) and its mechanism. The enzyme activity of lactate dehydrogenase (LDH) and the expression of RUNX family transcription factor 2 (Runx2), OPN, OCN in BMSCs were detected by quantitative real time polymerase chain reaction. At 14 days of induction, the mineralization ability and alkaline phosphatase (ALP) activity of cells in each group were observed by Alizarin Red S staining and ALP staining. In addition, the protein levels of tumor necrosis factor-α (TNF-α) and ß-catenin in BMSCs of each group were observed by western blot. After 14 days of the induction, the mineralization ability and ALP activity of BMSCs in the Ag2 O-TiO2 -NTs group were significantly enhanced compared with those in the Ag2 O and TiO2 groups. Western blot analysis showed that the BMSCs in the Ag2 O-TiO2 -NTs group exhibited much lower protein level of TNF-α and higher protein level of ß-catenin than those in the Ag2 O and TiO2 groups.Ag2 O-TiO2 -NTs enhance the osteogenic activity of BMSCs by modulating TNF-α/ß-catenin signaling.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Fator de Necrose Tumoral alfa/metabolismo , beta Catenina/metabolismo , Cateninas/metabolismo , Cateninas/farmacologia , Medula Óssea/metabolismo , Células Cultivadas , Diferenciação Celular , Células-Tronco Mesenquimais/metabolismo , Células da Medula Óssea/metabolismo
5.
Nat Commun ; 15(1): 2232, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472194

RESUMO

Site- and stereoselective C-H functionalization is highly challenging in the synthetic chemistry community. Although the chemistry of vinyl cations has been vigorously studied in C(sp3)-H functionalization reactions, the catalytic enantioselective C(sp3)-H functionalization based on vinyl cations, especially for an unactivated C(sp3)-H bond, has scarcely explored. Here, we report an asymmetric copper-catalyzed tandem diyne cyclization/unactivated C(sp3)-H insertion reaction via a kinetic resolution, affording both chiral polycyclic pyrroles and diynes with generally excellent enantioselectivities and excellent selectivity factors (up to 750). Importantly, this reaction demonstrates a metal-catalyzed enantioselective unactivated C(sp3)-H functionalization via vinyl cation and constitutes a kinetic resolution reaction based on diyne cyclization. Theoretical calculations further support the mechanism of vinyl cation-involved C(sp3)-H insertion reaction and elucidate the origin of enantioselectivity.

6.
World J Diabetes ; 15(1): 105-125, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38313853

RESUMO

BACKGROUND: Development of end-stage renal disease is predominantly attributed to diabetic nephropathy (DN). Previous studies have indicated that myricetin possesses the potential to mitigate the pathological alterations observed in renal tissue. Nevertheless, the precise molecular mechanism through which myricetin influences the progression of DN remains uncertain. AIM: To investigate the effects of myricetin on DN and explore its potential therapeutic mechanism. METHODS: Db/db mice were administered myricetin intragastrically on a daily basis at doses of 50 mg/kg or 100 mg/kg for a duration of 12 wk. Subsequently, blood and urine indexes were assessed, along with examination of renal tissue pathology. Kidney morphology and fibrosis were evaluated using various staining techniques including hematoxylin and eosin, periodic acid-Schiff, Masson's trichrome, and Sirius-red. Additionally, high-glucose culturing was conducted on the RAW 264.7 cell line, treated with 25 mM myricetin or co-administered with the PI3K/Akt inhibitor LY294002 for a period of 24 h. In both in vivo and in vitro settings, quantification of inflammation factor levels was conducted using western blotting, real-time qPCR and ELISA. RESULTS: In db/db mice, administration of myricetin led to a mitigating effect on DN-induced renal dysfunction and fibrosis. Notably, we observed a significant reduction in expressions of the kidney injury markers kidney injury molecule-1 and neutrophil gelatinase associated lipocalin, along with a decrease in expressions of inflammatory cytokine-related factors. Furthermore, myricetin treatment effectively inhibited the up-regulation of tumor necrosis factor-alpha, interleukin-6, and interluekin-1ß induced by high glucose in RAW 264.7 cells. Additionally, myricetin modulated the M1-type polarization of the RAW 264.7 cells. Molecular docking and bioinformatic analyses revealed Akt as the target of myricetin. The protective effect of myricetin was nullified upon blocking the polarization of RAW 264.7 via inhibition of PI3K/Akt activation using LY294002. CONCLUSION: This study demonstrated that myricetin effectively mitigates kidney injury in DN mice through the regulation of macrophage polarization via the PI3K/Akt signaling pathway.

7.
Org Biomol Chem ; 22(4): 745-752, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-37982316

RESUMO

Ligand 1, a rim-differentiated pillar[5]arene macrocycle modified with five naphthalimide groups through click chemistry, serves as an effective ratiometric fluorescent chemosensor for Cu2+. In contrast to the monomeric naphthalimide control compound 2, which shows only monomer emission, ligand 1 demonstrates dual emission characteristics encompassing both the monomer and excimer of the naphthalimide moieties. The binding properties of ligand 1 toward 15 different metal ions were systematically investigated in CH2Cl2/CH3CN (v/v, 1 : 1) by UV-vis and fluorescence spectroscopy. Remarkably, ligand 1 exhibits exceptional selectivity for Cu2+ ions. Upon complexation with Cu2+, the excimer emission of ligand 1 diminishes, concomitant with an enhancement of its monomer emission. The binding ratio for 1·Cu2+ was determined to be 1 : 1, with an association constant of (3.39 ± 0.40) × 105 M-1 calculated using a nonlinear least-squares curve-fitting method. Furthermore, the limit of detection (LOD) was found to be 185 ± 7 nM. Our results from 1H NMR titration, high-resolution mass spectrometry analysis and density functional theory calculations of 1·Cu2+ suggest synergistic coordination between Cu2+ and the triazole groups on ligand 1.

8.
Can J Urol ; 30(6): 11714-11723, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38104328

RESUMO

INTRODUCTION: Robot-assisted laparoscopic prostatectomy (RALP) and transurethral resection of bladder tumor (TURBT) are two common surgeries for prostate and bladder cancer. We aim to assess the trends in the site of care for RALP and TURBT before and after the COVID outbreak. MATERIALS AND METHODS: We identified adults who underwent RALP and TURBT within the California Healthcare Cost and Utilization Project State Inpatient Database and the State Ambulatory Surgery Database between 2018 and 2020. Multivariable analysis and spline analysis with a knot at COVID outbreak were performed to investigate the time trend and factors associated with ambulatory RALP and TURBT. RESULTS: Among 17,386 RALPs, 6,774 (39.0%) were ambulatory. Among 25,070 TURBTs, 21,573 (86.0%) were ambulatory. Pre-COVID, 33.5% of RALP and 85.3% and TURBT were ambulatory, which increased to 53.8% and 88.0% post-COVID (both p < 0.001). In multivariable model, RALP and TURBT performed after outbreak in March 2020 were more likely ambulatory (OR 2.31, p < 0.0001; OR 1.25, p < 0.0001). There was an overall increasing trend in use of ambulatory RALP both pre- and post-COVID, with no significant change of trend at the time of outbreak (p = 0.642). TURBT exhibited an increased shift towards ambulatory sites post-COVID (p < 0.0001). CONCLUSIONS: We found a shift towards ambulatory RALP and TURBT following COVID outbreak. There was a large increase in ambulatory RALP post-COVID, but the trend of change was not significantly different pre- and post-COVID - possibly due to a pre-existing trend towards ambulatory RALP which predated the pandemic.


Assuntos
COVID-19 , Laparoscopia , Neoplasias da Próstata , Neoplasias da Bexiga Urinária , Masculino , Adulto , Humanos , Pandemias , Prostatectomia , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Procedimentos Cirúrgicos Ambulatórios , COVID-19/epidemiologia , Neoplasias da Bexiga Urinária/cirurgia
9.
J Mater Chem B ; 11(46): 11135-11149, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-37964663

RESUMO

Most hydrogel dressings are designed for skin wounds in flat areas, and few are focused on the joint skin regions which undergo frequent movement. The mismatch of mechanical properties and poor fit between a hydrogel dressing and a wound in joint skin results in hydrogel shedding, bacterial infection and delayed healing. Therefore, it is of great significance to design and prepare a multifunctional hydrogel with high tensile and tissue-adhesive strength as well as other therapeutic effects for the treatment of joint skin wounds. In this work, a multifunctional hydrogel was reasonably prepared by simply mixing polyvinyl alcohol (PVA), borax, tannic acid (TA) and iron(III) chloride in certain proportions, which was further used to treat the skin wounds at the joint of the hind limb. Acting as the physical crosslinkers, borax and TA dynamically bond with PVA and provide the resulting hydrogel with strong tensile, fast shape-adaptive and self-healing properties. The photothermal bacteriostatic activity of the hydrogel is attributed to the formation of a metallic polyphenol network (MPN) between ferric ions and TA. In addition, the hydrogel exhibits high levels of adhesion, hemostatic performance, antioxidant abilities, and biocompatibility, and shows great potential to promote joint skin wound healing.


Assuntos
Adesivos , Hidrogéis , Adesivos/farmacologia , Hidrogéis/farmacologia , Compostos Férricos , Bandagens , Ferro
10.
Heliyon ; 9(11): e21941, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38034620

RESUMO

Background: Although vaccinations and antiviral drugs are widely used in the clinical treatment worldwide, there is little investigation on the clinical outcomes and effectiveness of oral Azvudine tablets (FNC) treatment in COVID-19 hospitalized patients. The previous data showed Azvudine treatment was closely related to reduced virus shedding time, but the potential role of Azvudine on inflammatory response is scarce. Thus, this study is to investigate inflammatory predictors and effectiveness of oral Azvudine tablets treatment in COVID-19 hospitalized patients. Methods: A total of 600 out of hospitalized patients were retrospectively collected over a 2-month period, of whom 60 out of hospitalized patients infected SARS-CoV-2. 32 of hospitalized patients who received Azvudine tablets were collected and the rest did not. Oral Azvudine tablets treatment: 5 mg/day for 7-14 days. We analyzed the routine blood tests, blood coagulation test, NT-proBNP, Troponin (cTNl), Creatine kinase MB (CK-MB) after oral Azvudine tablets treatment compared with that in before oral Azvudine tablets treatment. Also, we compared the CT chest and length of Stay after Azvudine treatment. Results: We found that the number and percentage of eosinophil increased significantly, but the levels of C-reactive protein (C-RP) and IL-6 reduced remarkably after Azvudine treatment. In blood coagulation tests, the results showed that activated partial thromboplastin time (APTT) (mean ± SEM: 2.950 ± 2.268s) and fibrinogen (mean ± SEM: 0.8910 ± 0.5134g/L) downregulated slightly, while there was similar in the level of D-Dimer (mean ± SEM: 0.1660 ± 0.3108 µg/mL) before and after Azvudine treatment. The expression of NT-proBNP reduced in Azvudine treatment (mean ± SEM: 897.1 ± 557.1pg/mL). Chest computed tomography (CT) scan reports also demonstrated that Azvudine treatment improved lung symptoms in COVID-19 hospitalized patients. Moreover, there is no difference in the average of length of stay in Azvudine treatment (the average of LOS days: 9.0) and no treatment (the average of LOS days: 9.0). Conclusion: Oral Azvudine tablets treatment was associated with decreased inflammatory response and improved blood coagulation function, which should be substantial clinical benefits in COVID-19 hospitalized patients.

12.
Int J Biol Macromol ; 253(Pt 4): 126854, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37729986

RESUMO

Melanoma excision surgery is usually accompanied by neoplasm residual, tissue defect, and bacterial infection, resulting in high tumor recurrence and chronic wound. Nanocomposite hydrogels can satisfy the twin requirements of avoiding tumor recurrence and skin wound healing following skin melanoma surgery due to their photothermal anti-tumor and anti-bacterial activities. In this study, carboxymethyl chitosan, oxidized fucoidan and polyphenol-metal nanoparticle (PMN) of tannic acid capped gold nanoparticles were used to fabricate multifunctional nanocomposite hydrogels through Schiff base reaction. The prepared hydrogel demonstrated outstanding photothermal effect, and the controlled high temperature will rapidly kill melanoma cells as well as bacteria within 10 min. Good injectability, self-healing and adhesion combined with high reactive oxygen species (ROS) scavenging capacity, hemostasis and biocompatibility made this hydrogel platform perfect for the postoperative treatment of melanoma and promoting wound healing. With the assistance of NIR irradiance, hydrogel can inhibit tumor tissue proliferation and promote tumor cell apoptosis, thereby helping to prevent melanoma recurrence after surgical removal of tumors. Simultaneously, the irradiance heat and polyphenol component kill bacteria on the wound surface, eliminate ROS, inhibit inflammatory responses, and promote angiogenesis, collagen deposition, and skin regeneration, all of which help to speed up wound healing.


Assuntos
Quitosana , Melanoma , Nanopartículas Metálicas , Humanos , Polifenóis/farmacologia , Hidrogéis/farmacologia , Quitosana/farmacologia , Ouro , Nanogéis , Recidiva Local de Neoplasia , Espécies Reativas de Oxigênio , Melanoma/terapia , Antibacterianos
13.
Environ Sci Technol ; 57(34): 12732-12740, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37590181

RESUMO

Nonphotosynthetic microorganisms are typically unable to directly utilize light energy, but light might change the metabolic pathway of these bacteria indirectly by forming intermediates such as reactive oxygen species (ROS). This work investigated the role of light on nitrogen conversion by anaerobic ammonium oxidation (anammox) consortia. The results showed that high intensity light (>20000 lx) caused ca. 50% inhibition of anammox activity, and total ROS reached 167% at 60,000 lx. Surprisingly, 200 lx light was found to induce unexpected promotion of the nitrogen conversion rate, and ultraviolet light (<420 nm) was identified as the main contributor. Metagenomic and metatranscriptomic analyses revealed that the gene encoding cytochrome c peroxidase was highly expressed only under 200 lx light. 15N isotope tracing, gene abundance quantification, and external H2O2 addition experiments showed that photoinduced trace H2O2 triggered cytochrome c peroxidase expression to take up electrons from extracellular nonfermentative organics to synthesize NADH and ATP, thereby expediting nitrogen dissimulation of anammox consortia. External supplying reduced humic acid into a low-intensity light exposure system would result in a maximal 1.7-fold increase in the nitrogen conversion rate. These interesting findings may provide insight into the niche differentiation and widespread nature of anammox bacteria in natural ecotopes.


Assuntos
Oxidação Anaeróbia da Amônia , Citocromo-c Peroxidase , Elétrons , Peróxido de Hidrogênio , Espécies Reativas de Oxigênio , Nitrogênio
15.
JAMA Netw Open ; 6(7): e2325291, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37498602

RESUMO

Importance: Geographic access, including mode of transportation, to health care facilities remains understudied. Objective: To identify sociodemographic factors associated with public vs private transportation use to access health care and identify the respondent, trip, and community factors associated with longer distance and time traveled for health care visits. Design, Setting, and Participants: This cross-sectional study used data from the 2017 National Household Travel Survey, including 16 760 trips or a nationally weighted estimate of 5 550 527 364 trips to seek care in the United States. Households that completed the recruitment and retrieval survey for all members aged 5 years and older were included. Data were analyzed between June and August 2022. Exposures: Mode of transportation (private vs public transportation) used to seek care. Main Outcomes and Measures: Survey-weighted multivariable logistic regression models were used to identify factors associated with public vs private transportation and self-reported distance and travel time. Then, for each income category, an interaction term of race and ethnicity with type of transportation was used to estimate the specific increase in travel burden associated with using public transportation compared a private vehicle for each race category. Results: The sample included 12 092 households and 15 063 respondents (8500 respondents [56.4%] aged 51-75 years; 8930 [59.3%] females) who had trips for medical care, of whom 1028 respondents (6.9%) were Hispanic, 1164 respondents (7.8%) were non-Hispanic Black, and 11 957 respondents (79.7%) were non-Hispanic White. Factors associated with public transportation use included non-Hispanic Black race (compared with non-Hispanic White: adjusted odds ratio [aOR], 3.54 [95% CI, 1.90-6.61]; P < .001) and household income less than $25 000 (compared with ≥$100 000: aOR, 7.16 [95% CI, 3.50-14.68]; P < .001). The additional travel time associated with use of public transportation compared with private vehicle use varied by race and household income, with non-Hispanic Black respondents with income of $25 000 to $49 999 experiencing higher burden associated with public transportation (mean difference, 81.9 [95% CI, 48.5-115.3] minutes) than non-Hispanic White respondents with similar income (mean difference, 25.5 [95% CI, 17.5-33.5] minutes; P < .001). Conclusions and Relevance: These findings suggest that certain racial, ethnic, and socioeconomically disadvantaged populations rely on public transportation to seek health care and that reducing delays associated with public transportation could improve care for these patients.


Assuntos
Acesso aos Serviços de Saúde , Viagem , Feminino , Humanos , Masculino , Estudos Transversais , Inquéritos e Questionários , Estados Unidos , Pessoa de Meia-Idade , Idoso
16.
J Org Chem ; 88(13): 8441-8453, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37276376

RESUMO

Herein, we present a facile synthetic methodology to produce a range of N-(CH2-aryl/alkyl)-substituted N-(pyridin-2-yl)benzamides via palladium-mediated C(sp3)-H bond activation. The N-methyl-N-(pyridin-2-yl)benzamide precursor was first reacted with palladium(II) acetate in a stoichiometric manner to obtain the key dinuclear palladacycle intermediates, whose structures were elucidated by mass spectrometric, NMR spectroscopic, and X-ray crystallographic studies in detail. The subsequent C(sp3)-H bond functionalizations on the N-methyl group of the starting substrate show facile productions of the corresponding N-(CH2-aryl/alkyl)-substituted N-(pyridin-2-yl)benzamides with good functional group tolerance. A plausible mechanism was proposed based on density functional theory calculations in conjunction with kinetic isotope effect experiments. Finally, the synthetic transformation from the prepared N-(CH2-aryl)-N-(pyridin-2-yl)benzamides through debenzoylation to N-(CH2-aryl)-2-aminopyridine was successfully demonstrated.


Assuntos
Benzamidas , Paládio , Paládio/química , Catálise , Alquilação
17.
Acta Biomater ; 166: 224-240, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37207743

RESUMO

Bacterial infection in the most mobile area usually leads to delayed healing and functional restriction, which has been a long-term challenge in clinic. Developing hydrogel-based dressings with mechanical flexibly, high adhesive and anti-bacterial properties, will contribute to the healing and therapeutic effects especially for this typical skin wound. In this work, composite hydrogel named PBOF through multi-reversible bonds between polyvinyl alcohol, borax, oligomeric procyanidin and ferric ion demonstrated a 100 times ultra-stretch ability, 24 kPa of highly tissue-adhesive, rapid shape-adaptability within 2 min and self-healing feature within 40 s, was designed as the multifunctional wound dressing for the Staphylococcus aureus-infected skin wound in the mice nape model. Besides, this hydrogel dressing could be easily removed on-demand within 10 min by water. The rapid disassembly of this hydrogel is related to the formation of hydrogen bonds between polyvinyl alcohol and water. Moreover, the multifunctional properties of this hydrogel include strong anti-oxidative, anti-bacteria and hemostasis derived from oligomeric procyanidin and photothermal effect of ferric ion/polyphenol chelate. The killing ratio of the hydrogel on Staphylococcus aureus in infected skin wound reached 90.6% when exposed to 808 nm irradiation for 10 min. Simultaneously, reduced oxidative stress, suppressed inflammation, and promoted angiogenesis all together accelerated wound healing. Therefore, this well-designed multifunctional PBOF hydrogel holds great promise as skin wound dressing especially in the high mobile regions of the body. STATEMENT OF SIGNIFICANCE: An ultra-stretchable, highly tissue-adhesive, and rapidly shape-adaptive, self-healing and on-demand removable hydrogel based on multi-reversible bonds among polyvinyl alcohol, borax, oligomeric procyanidin and ferric ion is designed as dressing material for infected wound healing in the movable nape. The rapid on-demand removal of the hydrogel relates to the formation of hydrogen bonds between polyvinyl alcohol and water. This hydrogel dressing shows strong antioxidant capacity, rapid hemostasis and photothermal antibacterial ability. This is derived from oligomeric procyanidin and thephotothermal effect of ferric ion/polyphenol chelate, which eliminates bacterial infection, reduces oxidative stress, regulates inflammation, promotes angiogenesis, and finally accelerates the infected wound healing in movable part.


Assuntos
Proantocianidinas , Infecções Estafilocócicas , Adesivos Teciduais , Animais , Camundongos , Hidrogéis/farmacologia , Proantocianidinas/farmacologia , Álcool de Polivinil , Cicatrização , Antibacterianos/farmacologia , Bandagens
18.
Biotechnol Biofuels Bioprod ; 16(1): 91, 2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37245019

RESUMO

BACKGROUND: With its high nutritional value and productivity, Italian ryegrass as a biomass feedstock constantly supplies rumen degradable nitrogen and digestible fiber to ruminants. However, biofuel production is easily reduced during ensiling due to the high-moisture content of Italian ryegrass, leading to economic losses. Lactic acid bacteria inoculants could improve lignocellulosic degradation and fermentation quality and decrease dry matter loss during the bioprocessing of silage. Therefore, this study analyzed the effects of Lactobacillus buchneri TSy1-3 (HE), Lactobacillus rhamnosus BDy3-10 (HO), and the combination of HE and HO (M) on fermentation quality, bacterial community and metabolome in high-moisture Italian ryegrass silage during ensiling. RESULTS: The results showed that the pH value was significantly lower in the HO groups than in the other treatments at the end of ensiling, and the dry matter and acetic acid contents were significantly higher in the HO group than in the other inoculated groups. All inoculants decreased the diversity of the bacterial community and significantly increased the relative abundance of Lactobacillus. Inoculation with HO significantly improved the concentrations of organic acids, dipeptides, ferulic acid, apigenin, and laricitrin. Compared with Lactobacillus buchneri TSy1-3 (HE), HO significantly upregulated the flavonoid compounds in the flavone and flavonol biosynthesis pathway. CONCLUSIONS: Overall, these findings suggest that inoculation with HO was beneficial for the development of Italian ryegrass as a biomass feedstock, improving fermentation quality, accelerating changes in bacterial community composition and increasing biofunctional metabolites in high-moisture Italian ryegrass silage.

19.
J Org Chem ; 88(13): 8703-8708, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37246907

RESUMO

Herein, we reported the heterogeneous photocatalytic C-H alkylation of indoles with diazo compounds using graphitic carbon nitride (g-C3N4) as the photocatalyst. The reaction was carried out under a simple operation and mild conditions. In addition, the catalyst was found to be stable and reusable after five reaction cycles. The photochemical reaction proceeds via an intermediary of a carbon radical, which is generated from diazo compounds through a visible-light-promoted proton-coupled electron transfer (PCET) process.


Assuntos
Indóis , Prótons , Carbono , Nitrilas/química , Compostos Azo , Corantes
20.
Artigo em Inglês | MEDLINE | ID: mdl-37076463

RESUMO

INTRODUCTION: Aspirin is used to prevent and treat cardiovascular diseases; however, some patients develop aspirin resistance. AIM: We aimed to explore the potential molecular mechanisms underlying aspirin resistance in people living in the Chinese plateau area. METHODS: In total, 91 participants receiving aspirin treatment from the Qinghai plateau area were divided into the aspirin resistance and aspirin sensitivity groups. Genotyping was performed using the Sequence MASSarray. Differentially mutated genes between the two groups were analyzed using MAfTools. The annotation of differentially mutated genes was conducted based on the Metascape database. RESULTS AND DISCUSSION: In total, 48 differential SNP and 22 differential InDel mutant genes between the aspirin resistance and aspirin sensitivity groups were screened using Fisher's exact test (P < 0.05). After the χ2 test, a total of SNP mutant genes, including ZFPL1 and TLR3, and 19 InDel mutant genes were found to be differentially expressed between the two groups (P < 0.05). Functional analysis revealed that these differential SNP mutations were mainly enriched in aspirin resistance pathways, such as the Wnt signaling pathway. Furthermore, these genes were related to many diseases, including various aspirin indications. CONCLUSION: This study identified several genes and pathways that could be involved in arachidonic acid metabolic processes and aspirin resistance progression, which will provide a theoretical understanding of the molecular mechanism of aspirin resistance.

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