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1.
Langmuir ; 40(2): 1503-1514, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38156944

RESUMO

Surfactant reduces the surface tension of liquids, resulting in improved emulsion stability, and there is great interest in pesticide additives. Ethoxylate is often used as a pesticide emulsifier. However, the degree of ethoxylation and the existence of dioxane byproducts can significantly affect the performance of emulsifiers. Here, a series of polyoxyethylene tallow amines with the addition of different numbers of ethylene oxide (EO) were synthesized and characterized. Their physical and chemical performances were measured. The ability of POEA as a surfactant to reduce water surface tension and the surface adsorption of molecules were assessed based on the static and dynamic surface tensions. The results show that the surfactant molecules preferentially form a saturated adsorption layer in solution, and the mixed-diffusion-kinetics mechanism dominates the adsorption process. With the increase of the EO addition number, the emulsifying property of POEA increases, while the wetting property gradually decreases and the contact angle increases. These results can provide a basis for the selection of pesticide additives. At the same time, the mechanism of removing dioxane by ethoxylate is described, and a simple and low-consumption method is put forward to reduce the dioxane content. It provides a new idea for the removal of dioxane.

2.
BMC Gastroenterol ; 24(1): 257, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39123140

RESUMO

BACKGROUND: Construct deep learning models for colonoscopy quality control using different architectures and explore their decision-making mechanisms. METHODS: A total of 4,189 colonoscopy images were collected from two medical centers, covering different levels of bowel cleanliness, the presence of polyps, and the cecum. Using these data, eight pre-trained models based on CNN and Transformer architectures underwent transfer learning and fine-tuning. The models' performance was evaluated using metrics such as AUC, Precision, and F1 score. Perceptual hash functions were employed to detect image changes, enabling real-time monitoring of colonoscopy withdrawal speed. Model interpretability was analyzed using techniques such as Grad-CAM and SHAP. Finally, the best-performing model was converted to ONNX format and deployed on device terminals. RESULTS: The EfficientNetB2 model outperformed other architectures on the validation set, achieving an accuracy of 0.992. It surpassed models based on other CNN and Transformer architectures. The model's precision, recall, and F1 score were 0.991, 0.989, and 0.990, respectively. On the test set, the EfficientNetB2 model achieved an average AUC of 0.996, with a precision of 0.948 and a recall of 0.952. Interpretability analysis showed the specific image regions the model used for decision-making. The model was converted to ONNX format and deployed on device terminals, achieving an average inference speed of over 60 frames per second. CONCLUSIONS: The AI-assisted quality system, based on the EfficientNetB2 model, integrates four key quality control indicators for colonoscopy. This integration enables medical institutions to comprehensively manage and enhance these indicators using a single model, showcasing promising potential for clinical applications.


Assuntos
Colonoscopia , Aprendizado Profundo , Controle de Qualidade , Colonoscopia/normas , Humanos , Pólipos do Colo/diagnóstico por imagem , Pólipos do Colo/diagnóstico
3.
Surg Endosc ; 38(7): 3838-3848, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38819464

RESUMO

BACKGROUND: Small intestinal stromal tumors (SISTs) typically require surgical treatment. However, the impact of lymphadenectomy (LA) on long-term prognosis in patients remains unclear. Therefore, we plan to analyze the effect of LA on the prognosis of patients with SISTs using the Surveillance, Epidemiology, and End Results (SEER) database. METHODS: Data on SISTs patients between 2000 and 2019 were obtained from the SEER database. Multiple imputation (MI) was employed to handle missing data, while propensity score matching (PSM) was conducted to mitigate selection bias in the comparative assessments between the LA group and the No-LA group. Kaplan-Meier analyses and multivariate Cox proportional hazards models were utilized to evaluate both overall survival (OS) and cancer-specific survival (CSS). RESULTS: A total of 2412 patients diagnosed with SISTs were included in the study, with 879 undergoing LA and 1533 not undergoing LA. There were no significant differences observed between the two cohorts concerning long-term OS (hazard ratio [HR] 0.97, 95% confidence interval [CI] 0.84-1.13, P = 0.720) and CSS (HR 1.05, 95% CI 0.86-1.29, P = 0.622). After PSM, 1596 patients (798 in the LA group and 789 in the No-LA group) were matched for comparison. There was also no difference in long-term OS and CSS between the two groups. Subgroup analysis revealed that in the age group > 60 years, the CSS in the No-LA group was superior to that in the LA group. Multivariate Cox regression analysis revealed that age, M stage, marital status, and mitotic rate are significant risk factors influencing OS and CSS. CONCLUSIONS: Conducting LA in patients with SISTs does not enhance long-term prognosis. For patients aged over 60 years, it may be more advisable to refrain from performing LA.


Assuntos
Tumores do Estroma Gastrointestinal , Excisão de Linfonodo , Programa de SEER , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Prognóstico , Idoso , Tumores do Estroma Gastrointestinal/cirurgia , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/mortalidade , Pontuação de Propensão , Intestino Delgado/patologia , Intestino Delgado/cirurgia , Estudos Retrospectivos , Adulto , Taxa de Sobrevida , Neoplasias Intestinais/cirurgia , Neoplasias Intestinais/patologia , Neoplasias Intestinais/mortalidade , Estimativa de Kaplan-Meier
4.
BMC Womens Health ; 24(1): 27, 2024 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-38184568

RESUMO

BACKGROUND: Postpartum dysfunctions and complications can occur in women. However, functional assessment should be conducted to make treatment plans before any intervention is implemented. In this context, the International Classification of Functioning, Disability and Health (ICF) may be a useful tool for women postpartum to document functional data and set rehabilitation goals. The purpose of this study was to determine the corresponding domains that should be considered in the evaluation of women's postpartum functioning based on the International Classification of Functioning, Disability and Health (ICF) model using the Delphi method. METHODS: Fifteen domestic experts were invited to conduct two rounds of expert consensus survey on the ICF-based postpartum functional assessment category pool obtained through literature retrieval, clinical investigation, and reference to relevant literature. The sample was medical staff with professional knowledge of women's health. The opinions of experts were summarized, and the positive coefficient, authority coefficient and coordination degree of experts were calculated. RESULTS: A total of 15 domestic experts participated in this expert consensus. Through two rounds of a questionnaire survey, 69 items were finally selected to form the ICF-based postpartum functional assessment tool for women. The items included 32 items of body function, 12 items of body structure, 17 items of activity and participation, and 8 items of environmental factors. In addition, we identified 8 items of personal factors. The expert positive coefficients of the two rounds of expert consensus were both 100%, the authority coefficient was 0.789, and the coefficient of variation was between 0.09 to 0.31. CONCLUSION: A postpartum functional assessment tool for women based on the ICF model was constructed based on the Delphi method, which can provide more comprehensive health management and life intervention for postpartum women. TRIAL REGISTRATION: The Registration number of the Chinese Clinical Trial Registry is ChiCTR2200066163, 25/11/2022.


Assuntos
Classificação Internacional de Funcionalidade, Incapacidade e Saúde , Período Pós-Parto , Feminino , Humanos , Correlação de Dados , Saúde da Mulher
5.
Analyst ; 148(21): 5380-5389, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37743718

RESUMO

Recently, amino acids other than glycine and taurine were found to be conjugated with bile acids by the gut microbiome in mouse and human. As potential diagnostic markers for inflammatory bowel disease and farnesoid X receptor agonists, their physiological effects and mechanisms, however, remain to be elucidated. A tool for the rapid and comprehensive annotation of such new metabolites is required. Thus, we developed a semi-empirical MS/MS library for bile acids conjugated with 18 common amino acids, including alanine, arginine, asparagine, aspartate, glutamine, glutamate, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, and valine. To investigate their fragmentation rules, these amino acids were chemically conjugated with lithocholic acid, deoxycholic acid, and cholic acid, and their accurate-mass MS/MS spectra were acquired. The common fragmentation patterns from the amino acid moieties were combined with 10 general bile acid skeletons to generate a semi-empirical MS/MS library of 180 structures. Software named BAFinder 2.0 was developed to combine the semi-empirical library in negative mode and the characteristic fragments in positive mode for automatic unknown identification. As a proof of concept, this workflow was applied to the LC-MS/MS analysis of the feces of human, beagle dogs, and rats. In total, 171 common amino acid-conjugated bile acids were annotated and 105 of them were confirmed with the retention times of synthesized compounds. To explore other potential bile acid conjugates, user-defined small molecules were in-silico conjugated with bile acids and searched in the fecal dataset. Four novel bile acid conjugates were discovered, including D-Ala-D-Ala, Lys(iso)-Gly, L-2-aminobutyric acid, and ornithine.


Assuntos
Aminoácidos , Espectrometria de Massas em Tandem , Animais , Ratos , Camundongos , Humanos , Cães , Cromatografia Líquida , Alanina , Metionina , Leucina , Tirosina , Glicina , Lisina , Treonina , Ácidos e Sais Biliares
6.
BMC Med Imaging ; 22(1): 123, 2022 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-35810273

RESUMO

OBJECTIVES: Accurate contouring of the clinical target volume (CTV) is a key element of radiotherapy in cervical cancer. We validated a novel deep learning (DL)-based auto-segmentation algorithm for CTVs in cervical cancer called the three-channel adaptive auto-segmentation network (TCAS). METHODS: A total of 107 cases were collected and contoured by senior radiation oncologists (ROs). Each case consisted of the following: (1) contrast-enhanced CT scan for positioning, (2) the related CTV, (3) multiple plain CT scans during treatment and (4) the related CTV. After registration between (1) and (3) for the same patient, the aligned image and CTV were generated. Method 1 is rigid registration, method 2 is deformable registration, and the aligned CTV is seen as the result. Method 3 is rigid registration and TCAS, method 4 is deformable registration and TCAS, and the result is generated by a DL-based method. RESULTS: From the 107 cases, 15 pairs were selected as the test set. The dice similarity coefficient (DSC) of method 1 was 0.8155 ± 0.0368; the DSC of method 2 was 0.8277 ± 0.0315; the DSCs of method 3 and 4 were 0.8914 ± 0.0294 and 0.8921 ± 0.0231, respectively. The mean surface distance and Hausdorff distance of methods 3 and 4 were markedly better than those of method 1 and 2. CONCLUSIONS: The TCAS achieved comparable accuracy to the manual delineation performed by senior ROs and was significantly better than direct registration.


Assuntos
Aprendizado Profundo , Neoplasias do Colo do Útero , Algoritmos , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Espécies Reativas de Oxigênio , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/radioterapia
7.
Ecotoxicol Environ Saf ; 223: 112616, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34371454

RESUMO

Nano zero-valent iron (nZVI) is a promising remediation material for Cd-contaminated soil, but questions remain regarding the effects of nZVI-induced Fe oxides on Cd availability with different soil types and moisture conditions. To identify the changes in Cd availability and Fe mineral phases resulting from the application of nZVI, three types of Cd-spiked soils with 0.1% nZVI amendment were incubated under different moisture conditions with water-holding capacities (WHCs) of 30%, 60%, and 180%. The availability of Cd was significantly decreased in yellow and black soils amended with nZVI, with fewer changes being observed in cinnamon soil. The limited effect of nZVI on Cd stabilization was due to the extremely low content of poorly crystalline Fe phases in cinnamon soil. The Cd stabilization efficiency of nZVI was higher in the flooding soils (180% WHC) than in the non-flooding yellow and black soils (30% and 60% WHC, respectively). Moreover, the addition of nZVI promoted the formation of less-available forms of Cd (Fe-oxide-bound Cd in yellow soil and Fe-oxide-bound and organic-material-bound Cd in black soil) under the flooding condition. The decrease in extractable Cd was strongly related to the increase in poorly crystalline Fe(Ⅱ) mineral phases among the three soils and various soil moisture contents. Although 0.1% nZVI amendment induced the dissolution of Mn oxides, it did not hinder the Cd stabilization in the three soils. Overall, this study indicates that increased amounts of poorly crystalline Fe(Ⅱ) compounds due to nZVI amendment play a critical role in the stabilization of Cd in soils.


Assuntos
Recuperação e Remediação Ambiental , Poluentes do Solo , Cádmio/análise , Compostos Ferrosos , Ferro/análise , Minerais , Solo , Poluentes do Solo/análise
8.
Med Sci Monit ; 26: e925758, 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33116073

RESUMO

BACKGROUND The aim of this study was to assess the clinical effectiveness of scapula training exercises on shoulder function after surgery for rotator cuff injury. MATERIAL AND METHODS Forty-six patients with rotator cuff injury after surgery were randomized into the experiment group or control group. Both groups were treated with conventional therapeutic exercise and physical therapy, and scapular training exercise was added to the experiment group. Patient status was evaluated by Constant-Murley scale (CMS), visual analogue scale (VAS), and the active range of motion (ROM) of the shoulder before and after 6 weeks and 12 weeks of treatment. RESULTS After 6 weeks and 12 weeks of treatment, all evaluations of the 2 groups were significantly improved as compared with those before treatment (P0.05). After 12 weeks of treatment, all items in the experimental group were significantly improved compared to the control group (P<0.05). CONCLUSIONS The combination of conventional rehabilitation interventions and scapular training exercise were an effective treatment of the shoulder dysfunction. Moreover, increased Scapula training exercise had better effect on the improvement of shoulder function.


Assuntos
Terapia por Exercício/métodos , Lesões do Manguito Rotador/reabilitação , Manguito Rotador/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Manguito Rotador/cirurgia , Lesões do Manguito Rotador/cirurgia , Escápula/fisiopatologia , Ombro/fisiopatologia , Articulação do Ombro/fisiopatologia , Resultado do Tratamento
9.
Chemosphere ; 350: 141091, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38171399

RESUMO

Stabilization techniques are vital in controlling Cd soil pollution. Nano zero valent iron (nZVI) has been extensively utilized for Cd remediation owing to its robust adsorption and reactivity. However, the environmental stress-induced stability of Cd after nZVI addition remains unclear. A pot experiment was conducted to evaluate the Cd bioavailability in continuously flooded (130 d) soil after stabilization with nZVI. The findings indicated that nZVI application did not result in a decline in Cd concentration in rice, as compared to the no-nZVI control. Additionally, nZVI simultaneously increased the available Cd concentration, iron-manganese oxide-bound (OX) Mn fraction, and relative abundance of Fe(III)-reducing bacteria, but it decreased OX-Cd and Mn availability in soil. Cadmium in rice tissues was positively correlated with the available Cd in soil. The results of subsequent adsorption tests demonstrated that CdO was the product of Cd adsorption by the nZVI aging products. Conversely, Mn2+ decreased the adsorption capacity of Cd-containing solutions. These results underscore the crucial role of both biotic and abiotic factors in undermining the stabilization of nZVI under continuous flooding conditions. This study offers novel insights into the regulation of nZVI-mediated Cd stabilization efficiency in conjunction with biological inhibitors and functional modification techniques.


Assuntos
Recuperação e Remediação Ambiental , Poluentes do Solo , Ferro , Compostos Férricos , Cádmio/análise , Solo , Poluentes do Solo/análise
10.
Clin Respir J ; 18(8): e13806, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39118279

RESUMO

OBJECTIVE: Construction nomogram was to effectively predict long-term prognosis in patients with non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: The nomogram is developed by a retrospective study of 347 patients with NSCLC who underwent cardiopulmonary exercise testing (CPET) before surgery from May 2019 to February 2022. Cross-validation divided the data into a training cohort and validation cohort. The discrimination and accuracy ability of the nomogram were proofed by concordance index (C-index), calibration curve, receiver operating characteristic (ROC) curve, the area under the curve (AUC), and time-dependent ROC in validation cohort. RESULTS: Age, intraoperative blood loss, VO2 peak, and VE/VCO2 slope were included in the model of nomogram. The model demonstrated good discrimination and accuracy with C-index of 0.770 (95% CI: 0.712-0.822). AUC of 6 (AUC: 0.789, 95% CI: 0.726-0.851) and 12 months (AUC: 0.787, 95% CI: 0.724-0.850) were shown in ROC. Time-independent ROC maintains a good effect within 12 months. CONCLUSION: We developed a nomogram based on CPET. This model has a good ability of discrimination and accuracy. It could help clinicians to make treatment decision in clinical decision.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Teste de Esforço , Neoplasias Pulmonares , Nomogramas , Humanos , Masculino , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Feminino , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/fisiopatologia , Teste de Esforço/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Prognóstico , Idoso , Curva ROC
11.
PLoS One ; 19(5): e0302277, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38743665

RESUMO

Enhanced animal welfare has emerged as a pivotal element in contemporary precision animal husbandry, with bovine monitoring constituting a significant facet of precision agriculture. The evolution of intelligent agriculture in recent years has significantly facilitated the integration of drone flight monitoring tools and innovative systems, leveraging deep learning to interpret bovine behavior. Smart drones, outfitted with monitoring systems, have evolved into viable solutions for wildlife protection and monitoring as well as animal husbandry. Nevertheless, challenges arise under actual and multifaceted ranch conditions, where scale alterations, unpredictable movements, and occlusions invariably influence the accurate tracking of unmanned aerial vehicles (UAVs). To address these challenges, this manuscript proposes a tracking algorithm based on deep learning, adhering to the Joint Detection Tracking (JDT) paradigm established by the CenterTrack algorithm. This algorithm is designed to satisfy the requirements of multi-objective tracking in intricate practical scenarios. In comparison with several preeminent tracking algorithms, the proposed Multi-Object Tracking (MOT) algorithm demonstrates superior performance in Multiple Object Tracking Accuracy (MOTA), Multiple Object Tracking Precision (MOTP), and IDF1. Additionally, it exhibits enhanced efficiency in managing Identity Switches (ID), False Positives (FP), and False Negatives (FN). This algorithm proficiently mitigates the inherent challenges of MOT in complex, livestock-dense scenarios.


Assuntos
Algoritmos , Animais , Bovinos , Criação de Animais Domésticos/métodos , Dispositivos Aéreos não Tripulados , Bem-Estar do Animal , Aprendizado Profundo
12.
Environ Sci Pollut Res Int ; 30(14): 41107-41119, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36630040

RESUMO

Phthalic acid esters (PAEs) are widely used plasticizers found in consumer products, which enter the environment and pose severe threats to human health. Here, a new PAE-degrading enzyme EstJ6 was modified by combining mutagenesis strategies and a strong promoter replacement to improve its catalytic activity and expression level. Four mutants with enhanced activity were obtained by random mutation, among which EstJ6M1.1 exhibited the highest catalytic activity with an increase in catalytic activity by 2.9-fold toward dibutyl phthalate (DBP) than that of the wild-type (WT) enzyme. With these mutants as a template, a variant EstJ6M2 with 3.1-fold higher catalytic activity and 4.61 times higher catalytic efficiency (Kcat/Km) was identified by staggered extension PCR. Targeting four mutation sites of EstJ6M2, a variant EstJ6M3.1 was gained by site-directed saturation mutagenesis and displayed 4.3-fold higher activity and 5.97 times higher Kcat/Km than WT. The expression level of three mutants EstJ6M1.1, EstJ6M2, and EstJ6M3.1, as well as the WT, increased nearly threefold after a strong promoter replacement. These results provide a proof-theoretical basis and practicable pipeline for applying PAE-degrading enzymes.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Humanos , Dietilexilftalato/metabolismo , Ácidos Ftálicos/análise , Dibutilftalato/análise , Mutagênese , Ésteres
13.
Int J Biol Macromol ; 238: 124062, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-36933600

RESUMO

The widespread antibiotic resistance of bacteria has become one of the most severe threats to public health. However, the mechanisms that allow microbial acquisition of resistance are still poorly understood. In the present study, a novel BON domain-containing protein was heterologously expressed in Escherichia coli. It functions as an efflux pump-like to confer resistance to various antibiotics, especially for ceftazidime, with a >32-fold increase in minimum inhibitory concentration (MIC). The fluorescence spectroscopy experiment indicated that BON protein could interact with several metal ions, such as copper and silver, which has been associated with the induced co-regulation of antibiotic and heavy metal resistance in bacteria. Furthermore, the BON protein was demonstrated to spontaneously self-assemble into a trimer and generate a central pore-like architecture for antibiotic transporting. A WXG motif as a molecular switch is essential for forming the transmembrane oligomeric pores and controls the interaction between BON protein and cell membrane. Based on these findings, a mechanism termed "one-in, one-out", was proposed for the first time. The present study provides new insights into the structure and function of BON protein and a previously unidentified antibiotic resistance mechanism, filling the knowledge gap in understanding BON protein-mediated intrinsic antibiotic resistance.


Assuntos
Antibacterianos , Metais Pesados , Antibacterianos/farmacologia , Metais Pesados/farmacologia , Bactérias , Cobre , Prata , Escherichia coli/genética
14.
Med Phys ; 50(5): 3117-3126, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36842138

RESUMO

BACKGROUND: Radiotherapy initiation is a laborious and time-consuming process that involves multiple steps and units. Workflow automation is in demand to improve the work efficiency and patient experience. PURPOSE: The purposes of this study are to describe the technical characteristics and clinical performance of an AI-powered one-stop radiotherapy workflow for initial treatment based on CT-linac combination, and provide insight into the behavior of full-workflow automation in radiotherapy. METHODS: Based on a CT-integrated linear accelerator and AI model implementation, the so-called "All-in-One" workflow incorporates routine procedures from simulation, autosegmentation, autoplanning, image guidance, beam delivery, and in vivo quality assurance (QA) into one scheme, while the patient is on the treatment couch. Clinical outcomes of the new workflow were evaluated for 10 enrolled patients with rectal cancer. RESULTS: For the enrolled patients, manual modifications of the autosegmented target volumes were necessary. The Dice similarity coefficient and 95% Hausdorff distance before and after the modifications were 0.892 ± 0.061 and 18.2 ± 13.0 mm, respectively. The autosegmented normal tissues and automatic plans were clinically acceptable without any modifications or reoptimization. The pretreatment IGRT corrections were within 2 mm in all directions, and the EPID-based in vivo QA showed γ passing rate of above 97% (3%/3 mm/10% threshold) at all the checkpoints, better than the results of rectal patients who followed a routine workflow. The duration of the whole process was 23.2 ± 3.5 minutes for the enrolled patients, depending mostly on the time required for manual modification and plan evaluation. CONCLUSION: The All-in-One workflow enables full-process automation of radiotherapy via seamless procedure integration. Compared to the routine workflow, the one-stop solution shortens the time scale it takes to ready the first treatment from days to minutes, significantly improving the patient experience and the workflow efficiency, and it also shows potential to facilitate clinical application of online adaptive replanning.


Assuntos
Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Humanos , Fluxo de Trabalho , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Automação , Tomografia Computadorizada por Raios X , Dosagem Radioterapêutica
15.
J Agric Food Chem ; 71(28): 10683-10692, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37427858

RESUMO

Plipastatin is a cyclic lipopeptide synthesized by non-ribosomal peptide synthetases (NRPS), which has a diverse range of applications in postharvest preservation of fruits and vegetables, biological control, and feed processing. Whereas the yield of plipastatin in wild Bacillus sp. is low, its chemical structure is complex and challenging to synthesize, significantly limiting its production and application. ComQXPA-PsrfA, a quorum-sensing (QS) circuit from Bacillus amyloliquefaciens, was constructed in this study. Two QS promoters MuPsrfA and MtPsrfA, with 35 and 100% increased activity, respectively, were obtained by mutating the original promoter PsrfA. Thus, the natural promoter of plipastatin was replaced by a QS promoter to achieve the dynamic regulation of plipastatin, which increased the yield of plipastatin by 3.5 times. Integrating ComQXPA into plipastatin mono-producing M-24:MtPsrfA increased the yield of plipastatin to 3850 mg/L, representing the highest yield reported to date. Four new plipastatins were identified via UPLC-ESI-MS/MS and GC-MS analysis of fermentation products of mono-producing engineered strains. Among them, three plipastatins contained two double bonds in the fatty acid side chain, representing the first example of a new type of plipastatin. Our results indicate that the QS system ComQXPA-PsrfA of Bacillus can dynamically regulate plipastatin production, and the pipeline could be extended to the other strains to regulate target products dynamically.


Assuntos
Bacillus amyloliquefaciens , Bacillus , Bacillus subtilis , Bacillus amyloliquefaciens/genética , Espectrometria de Massas em Tandem , Bacillus/genética , Ácidos Graxos/química , Percepção de Quorum
16.
Sci Total Environ ; 899: 165705, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37487902

RESUMO

Nitrogen (N) addition can have substantial impacts on both aboveground and belowground processes such as plant productivity, microbial activity, and soil properties, which in turn alters the fate of soil organic carbon (SOC). However, how N addition affects various SOC fractions such as particulate organic carbon (POC) and mineral-associated organic carbon (MAOC), particularly in agroecosystem, and the underlying mechanisms remain unclear. In this study, plant biomass (grain yield, straw biomass, and root biomass), soil chemical properties (pH, N availability, exchangeable cations and amorphous Al/Fe - (hydr) oxides) and microbial characteristics (biomass and functional genes) in response to a N addition experiment (0, 150, 225, 300, and 375 kg ha-1) in paddy soil were investigated to explore the predominant controls of POC and MAOC. Our results showed that POC significantly increased, while MAOC decreased under N addition (p < 0.05). Correlation analysis and PLSPM results suggested that increased C input, as indicated by root biomass, predominated the increase in POC. The declined MAOC was not mainly dominated by microbial control, but was strongly associated with the attenuated mineral protection (especially Ca2+) induced by soil acidification under N addition. Collectively, our results emphasized the importance of combining C input and soil chemistry in predicting soil C dynamics and thereby determining soil organic C storage in response to N addition in rice agroecosystem.


Assuntos
Carbono , Solo , Solo/química , Carbono/análise , Nitrogênio/análise , Poeira/análise , Minerais , Grão Comestível/química , Microbiologia do Solo
17.
Foods ; 12(6)2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36981096

RESUMO

In the present study, a feruloyl esterase DLFae4 identified in our previous research was modified by error-prone PCR and site-directed saturation mutation to enhance the catalytic efficiency and acyltransferase activity further. Five mutants with 6.9-118.9% enhanced catalytic activity toward methyl ferulate (MFA) were characterized under the optimum conditions. Double variant DLFae4-m5 exhibited the highest hydrolytic activity (270.97 U/mg), the Km value decreased by 83.91%, and the Kcat/Km value increased by 6.08-fold toward MFA. Molecular docking indicated that a complex hydrogen bond network in DLFae4-m5 was formed, with four of five bond lengths being shortened compared with DLFae4, which might account for the increase in catalytic activity. Acyl transfer activity assay revealed that the activity of DLFae4 was as high as 1550.796 U/mg and enhanced by 375.49% (5823.172 U/mg) toward 4-nitrophenyl acetate when residue Ala-341 was mutated to glycine (A341G), and the corresponding acyl transfer efficiency was increased by 7.7 times, representing the highest acyltransferase activity to date, and demonstrating that the WGG motif was pivotal for the acyltransferase activity in family VIII carboxylesterases. Further experiments indicated that DLFae4 and variant DLFae4 (A341G) could acylate cyanidin-3-O-glucoside effectively in aqueous solution. Taken together, our study suggested the effectiveness of error-prone PCR and site-directed saturation mutation to increase the specific activity of enzymes and may facilitate the practical application of this critical feruloyl esterase.

18.
Musculoskelet Sci Pract ; 62: 102658, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36037744

RESUMO

OBJECTIVES: To investigate the effect of transcutaneous electrical acupoint stimulation (TEAS) combined with proprioceptive neuromuscular facilitation (PNF) on postural stability, muscle strength and pain in patients with tibial plateau fracture. METHOD: A 3-arm randomized controlled trial was conducted in 60 patients with tibial plateau fracture. Participants received one of the following interventions: standard treatment (ST group, n = 20), ST + PNF training (ST + PNF group, n = 20), ST + PNF training + TEAS intervention (ST + PNF + TEAS group, n = 20). All treatments lasted for six weeks. Participants' postural stability, muscle strength and pain were evaluated at baseline, after 3 and 6 weeks of intervention. RESULTS: After 3 weeks of intervention, Between-group comparisons showed that both the ST + PNF group and ST + PNF + TEAS group showed significantly greater performance than the ST group in the postural stability measure (P < 0.02) and pain score(P < 0.05). The peak torque of quadriceps extensors and flexors at the velocity of 60°/s was significantly higher in the ST + PNF + TEAS group than in the ST group (P < 0.02). After 6 weeks of intervention, only the ST + PNF + TEAS group was superior to the ST group in postural stability measure(P < 0.04) and in pain score (P < 0.05). The ST + PNF + TEAS group was significantly higher than the ST + PNF group and the ST group in the peak torque of quadriceps extensors at the velocity of 60°/s and 180°/s (P < 0.01). CONCLUSION: PNF training could improve dynamic postural stability and relieve pain at three weeks, while TEAS combined with PNF was more effective in relieving pain, strengthening muscle strength and improving dynamic postural stability at six weeks post-intervention.


Assuntos
Exercícios de Alongamento Muscular , Fraturas do Planalto Tibial , Humanos , Amplitude de Movimento Articular , Força Muscular/fisiologia , Dor
19.
Nat Commun ; 13(1): 6861, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36369422

RESUMO

Enantioenriched N-alkylindole compounds, in which nitrogen is bound to a stereogenic sp3 carbon, are an important entity of target molecules in the fields of biological, medicinal, and organic chemistry. Despite considerable efforts aimed at inventing methods for stereoselective indole functionalization, straightforward access to a diverse range of chiral N-alkylindoles in an intermolecular catalytic fashion from readily available indole substrates remains an ongoing challenge. In sharp contrast to existing C-N bond-forming strategies, here, we describe a modular nickel-catalyzed C-C coupling protocol that couples a broad array of N-indolyl-substituted alkenes with aryl/alkenyl/alkynyl bromides to produce chiral N-alkylindole adducts in single regioisomeric form, in up to 91% yield and 97% ee. The process is amenable to proceed under mild conditions and exhibit broad scope and high functional group compatibility. Utility is highlighted through late-stage functionalization of natural products and drug molecules, preparation of chiral building blocks.


Assuntos
Alcenos , Níquel , Níquel/química , Estereoisomerismo , Catálise , Alcenos/química , Indóis
20.
J Hazard Mater ; 424(Pt A): 127343, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34600388

RESUMO

Nano zero-valent iron (nZVI) is used for soil remediation; however, the impact of nZVI on soil solid iron phases and its interactions with soil microorganisms in relation to the fate of Cd in soil remains unclear. In the current study, we investigated the mechanisms underlying the change in mobility of Cd in exogenous Cd-contaminated soil with nZVI and γ radiation treatments. The results showed that nZVI treatment decreased Cd availability but also increased the soil pH and dissolved Mn and poorly crystalline Fe contents. However, the increased poorly crystalline Fe(II) levels contributed to a reduction in Cd availability in soils treated with nZVI by immobilizing Cd associated with Fe oxides, rather than by increasing pH or Mn oxide levels. Moreover, Cd stabilization efficiency was higher in γ-irradiated soils than in non-irradiated soils regardless of the Cd level, with noticeable differences in bacterial community composition between the non-irradiated and irradiated soils. The genera Bacillus, Pullulanibacillus, and Alicyclobacillus are important in the redox of poorly crystalline Fe(II)-containing minerals in non-irradiated soil. This research provides a new method for further improving the Cd stabilization efficiency of nZVI in combination with microbial iron oxidization inhibitors.


Assuntos
Recuperação e Remediação Ambiental , Poluentes do Solo , Cádmio/análise , Ferro/análise , Solo , Poluentes do Solo/análise
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