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A 13-year-old boy was admitted to the hospital with 1-month history of neck pain and a 2-week history of bilateral hip joint pain accompanied by low fever. Positron emission tomography-computed tomography (PET-CT) revealed the presence of a malignant tumor in the left kidney with metastases to the left renal hilum, retroperitoneum, para-aortic lymph nodes, and multiple bone sites throughout the body. Given that the patient's left kidney capsule was intact and the boundary with surrounding tissues was clear, left nephrectomy was performed. Postoperative pathological diagnosis showed desmoplastic small round cell tumor (DSRCT) of the left kidney. CAV-VIP alternating chemotherapy was given 20 days after the first stage surgery. After the end of the 6th cycle, the patient underwent surgery again. The tumor in front of the aorta and postcava, the greater omentum, the retroperitoneal lymph nodes and the hepatic hilum lymph nodes, and the visible tumors in the abdomen were removed. CAV-VIP alternating chemotherapy was continued after the second stage surgery. At the end of the 4th cycle of post operation chemotherapy, radiotherapy was started. An abdominal CT scan conducted 11 months after second-stage surgery did not reveal any recurrence of abdominal tumors; however bone metastases persisted. The patient is currently receiving oral targeted therapy with anlotinib while ongoing follow-up continues.
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Background and objectives The efficacy of antipsychotic drugs in improving negative symptoms of schizophrenia remains controversial. Psychological interventions, such as Social Skills Training (SST) and Social Cognition and Interaction Training (SCIT), have been developed and applied in clinical practice. The current meta-analysis was therefore conducted to evaluate the efficacy of controlled clinical trials using SST and SCIT on treating negative symptoms. Methods Systematical searches were carried out on PubMed, Web of Science, and PsycINFO databases. The standardized mean difference (SMD) with 95% confidence intervals (CI) was calculated to assess the effect size of SST/SCIT on negative symptoms. Subgroup and meta-regression analyses were conducted to explore sources of heterogeneity and identify potential factors that may influence their efficacy. Results A total of 23 studies including 1441 individuals with schizophrenia were included. The SST group included 8 studies with 635 individuals, and the SCIT group included 15 studies with 806 individuals. The effect size for the efficacy of SST on negative symptoms was -0.44 (95% CI: -0.60 to -0.28; p < 0.01), while SCIT was -0.16 (95% CI: -0.30 to -0.02; p < 0.01). Conclusions Our findings suggest that while both SST and SCIT can alleviate negative symptoms, the former appears to be more effective. Our results provide evidence-based guidance for the application of these interventions in both hospitalized and community individuals and can help inform the treatment and intervention of individuals with schizophrenia. (AU)
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Humanos , Esquizofrenia/terapia , Habilidades Sociais , Relações Interpessoais , Sintomas PsíquicosRESUMO
Objective: To investigate self-stigma's influence on schizophrenia patients' quality of life and its mediated impact by various factors. Methods: This study adopted a cross-sectional design and randomly selected 170 hospitalized patients with schizophrenia for evaluation. The assessment tools included the Positive and Negative Syndrome Scale (PANSS), Internalized Stigma of Mental Illness Scale (ISMI), Schizophrenia Quality of Life Scale (SQLS), and Coping Questionnaire for Schizophrenia Patients (CQSP), among others. Correlation analysis, regression analysis, and mediation analysis were used to test the correlation and mediation effects. Results: Self-stigma had a significant impact on quality of life (T = 8.13, p = 0.00). When self-stigma is used as a mediator, the problem-solving factor in coping strategies has an indirect effect on quality of life, which is significant (AB = -0.16, P = 0.02), while the avoidance factor in coping strategies has a direct effect on quality of life, which is significant (C' = 0.54, p < 0.001), and an indirect effect, which is also significant (AB = 0.25, p < 0.001). Conclusion: The study highlights the significant impact of self-stigma on the quality of life of schizophrenia patients, emphasizing the crucial roles of self-esteem and coping strategies. These findings suggest clinical interventions to improve quality of life should focus on reducing self-stigma, especially enhancing self-esteem and promoting adaptive coping strategies. By addressing these factors, we can better support the mental health and well-being of those with schizophrenia, offering an effective approach to rehabilitation.
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The development of nondestructive technology for the detection of seed viability is challenging. In this study, to establish a green and effective method for the viability assessment of single maize seeds, a two-stage seed viability detection method was proposed. The catalase (CAT) activity and malondialdehyde (MDA) content were selected as the most key biochemical components affecting maize seed viability, and regression prediction models were developed based on their hyperspectral information and a data fusion strategy. Qualitative discrimination models for seed viability evaluation were constructed based on the predicted response values of the selected key biochemical components. The results showed that the double components thresholds strategy achieved the highest discrimination accuracy (92.9%), providing a crucial approach for the rapid and environmentally friendly detection of seed viability.
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Catalase , Malondialdeído , Sementes , Zea mays , Zea mays/química , Zea mays/metabolismo , Zea mays/crescimento & desenvolvimento , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Malondialdeído/metabolismo , Malondialdeído/análise , Catalase/metabolismo , Catalase/química , Proteínas de Plantas/metabolismo , Proteínas de Plantas/química , Germinação , Química VerdeRESUMO
Enzymatic malonylation of natural glycosides provides a promising alternative method for drug-like malonylated glycosides supply. However, the catalytic potential and structural basis of plant malonyltransferase are far from being fully elucidated. This work identified a new malonyltransferase CtMaT1 from Cistanche tubulosa. It displayed unprecedented mono- and/or di-malonylation activity toward diverse glucosides with different aglycons. A "one-pot" system by CtMaT1 and a malonyl-CoA synthetase was established to biosynthesize nine new malonylated glucosides. Structural investigations revealed that CtMaT1 possesses an adequately spacious acyl-acceptor pocket capable of accommodating diverse glucosides. Additionally, it recognizes malonyl-CoA through strong electrotactic and hydrogen interactions. QM/MM calculation revealed the H167-mediated SN2 reaction mechanism of CtMaT1, while dynamic simulations detected the formation of stable hydrogen bonds between the glucose-6-OH group and H167, resulting in its high malonylation regiospecificity. Calculated energy profiles of two isomeric glycosides highlighted lower reaction energy barriers towards glucoside substrates, emphasizing CtMaT1's preference for glucosides. Furthermore, a mutant CtMaT1H36A with notably increased di-malonylation activity was obtained. The underlying molecular mechanism was illuminated through MM/GBSA binding free energy calculation. This study significantly advances the understanding of plant acyltransferases from both functional and protein structural perspectives, while also providing a versatile tool for enzymatic malonylation applications in pharmacology.
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A general approach for regioselective deacetylation at sugar 3-OH of peracetylated 6-deoxy-C-glucopyranosides mediated by BCl3 was developed. The approach could be extended to other sugar-derived 6-deoxy-C-glycopyranosides, such as those derived from mannose, galactose, and rhamnose, with deacetylation occurring at varied sugar hydroxyl groups, and further extended to 4-deoxy-C-glucopyranosides with deacetylation occurring at sugar 3-OH. The approach would enable access to synthetically challenging carbohydrate derivatives. A possible mechanism of the regioselectivity was proposed.
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Background: Postoperative pancreatic fistula (POPF) is a perilous complication that may arise subsequent to pancreaticoduodenectomy (PD). In recent times, there has been an escalating interest in employing machine learning (ML) techniques to aid in treatment decision-making. The purpose of this research is to assess the effectiveness of ML in comparison to conventional models, while also conducting an initial evaluation of the predictive capability of skeletal muscle index (SMI) concerning POPF. Methods: This retrospective observational study was carried out at The First Affiliated Hospital of Wenzhou Medical University from January 2012 to January 2021, encompassing data from 269 patients who underwent PD. After identifying independent factors associated with the condition, a logistic regression model was employed to construct a nomogram, alongside the establishment of five ML models. To assess their effectiveness, the best-performing ML model and nomogram were evaluated on a separate test group comprising 77 additional patients. The evaluation involved comparing the area under the curve (AUC) and Brier score. Results: Among the 269 patients studied, the incidence of POPF was found to be 56.9%, with 106 patients (69.3%) experiencing clinically-relevant POPF. We identified six independent factors associated with POPF, including body mass index (BMI), SMI, pancreatic duct dilatation, tumor size, triglyceride levels, and the ratio of aspartate aminotransferase to alanine aminotransferase (AST/ALT) on the first postoperative day. When evaluated on the test set, the Gaussian Naive Bayes (GNB) model, which was the best-performing ML model, achieved an AUC of 0.824 and a Brier score of 0.175. The corresponding performance indicators for the nomogram were 0.844 for AUC and 0.165 for the Brier score. Conclusions: This study found that there is minimal difference between ML and the nomogram based on logistic regression in predicting POPF. Additionally, SMI shows promise as a potential and practical tool for assessing the risk of POPF.
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PURPOSE: This paper explores the causes of paediatric inguinal hernia (PIH) recurrence after single-port laparoscopic percutaneous extraperitoneal closure (SPLPEC). METHOD: From January 2015 to December 2020, the clinical data of 3480 children with PIHs who underwent SPLPEC were retrospectively reviewed, including 644 children who underwent SPLPEC with a homemade single-hook hernia needle from January 2015 to December 2016 and 2836 children who underwent the SPLPEC with a double-hook hernia needle and hydrodissection from January 2017 to December 2020. There were 39 recurrences (including communicating hydrocele) during the 2-5 years of follow-up. The findings of redo-laparoscopy were recorded and correlated with the revised video of the first operation to analyse the causes of recurrence. RESULT: Thirty-three males and 6 females experienced recurrence, and 8 patients had a unilateral communicating hydrocele. The median time to recurrence was 7.1 months (0-38). There were 20 cases (3.11%) in the single-hook group and 19 cases (0.67%) in the double-hook group. Based on laparoscopic findings, recurrence most probably resulted from multiple factors, including uneven tension of the ligation (10 cases), missing part of the peritoneum (14 cases), loose ligation (8 cases), broken knot (5 cases), and knot reaction (2 cases). All children who underwent repeat SPLPEC were cured by double ligations or reinforcement with medial umbilical ligament. CONCLUSION: The main cause of recurrence is improper ligation. Tension-free and complete PIH ligation are critical to the success of surgery, which requires avoiding the peritoneum skip area and the subcutaneous and muscular tissues. Redo-laparoscopic surgery was suitable for the treatment of recurrent inguinal hernia (RIH). For giant hernias, direct ligation of the internal ring incorporating the medial umbilical ligament (DIRIM) may be needed.
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Hérnia Inguinal , Laparoscopia , Hidrocele Testicular , Masculino , Feminino , Criança , Humanos , Lactente , Hérnia Inguinal/etiologia , Hérnia Inguinal/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Herniorrafia/métodos , Laparoscopia/métodos , Hidrocele Testicular/cirurgia , RecidivaRESUMO
OBJECTIVES: Noninvasive brain stimulation (NIBS) has been shown to effectively alleviate negative and positive symptoms in patients with schizophrenia. However, its impact on depressive symptoms and general psychopathology symptoms (GPSs), which are crucial for functional outcomes, remains uncertain. We aimed to compare the efficacy of various NIBS interventions in treating depressive symptoms and GPSs. METHODS: We conducted a comprehensive search of multiple databases and performed a meta-analysis to evaluate the efficacy of NIBS in treating depressive symptoms and GPSs in schizophrenia. The effect sizes of NIBS for depression symptoms and GPSs were estimated using standard mean differences (SMDs) with 95% confidence intervals (CIs). Subgroup analyses were employed to examine potential influencing factors on the pooled SMD of NIBS for GPSs. RESULTS: Our search yielded 35 randomized controlled trials involving 1715 individuals diagnosed with schizophrenia. The protocol of this systematic review was registered with INPLASY (protocol ID: INPLASY202320082). Neither repetitive transcranial magnetic stimulation (rTMS) nor transcranial direct current stimulation (tDCS) demonstrated significant improvements in depressive symptoms compared to sham controls. NIBS exhibited a small-to-moderate effect size for GPSs, with a pooled SMD of -0.2956 (95% CI: -0.459 to -0.132) and a heterogeneity (I2) of 58.9% (95% CI: 41.5% to 71.1%; p < 0.01) based on a random-effects model. Subgroup analyses of different types of NIBS, different frequencies of rTMS, and different stimulation sites of rTMS revealed no significant differences. Only sex had a significant influence on the effect size of NIBS for general psychopathology symptoms (p < 0.05). However, rTMS might be superior to tDCS, and high-frequency rTMS outperformed low-frequency rTMS in treating GPSs. CONCLUSIONS: We found a small-to-moderate effect size of NIBS in alleviating GPSs in patients with schizophrenia. Both rTMS and tDCS were more effective than sham stimulation in reducing GPSs in schizophrenia. The frequency used was associated with rTMS efficacy for GPSs.
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Esquizofrenia , Estimulação Transcraniana por Corrente Contínua , Humanos , Estimulação Transcraniana por Corrente Contínua/métodos , Esquizofrenia/terapia , Estimulação Magnética Transcraniana/métodos , Manejo da Dor/métodos , Encéfalo/fisiologiaRESUMO
Pulmonary arterial hypertension (PAH) is a malignant cardiovascular disease. Eukaryotic initiation factor 2α (eIF2α) plays an important role in the proliferation of pulmonary artery smooth muscle cells (PASMCs) in hypoxia-induced pulmonary hypertension (HPH) rats. However, the regulatory mechanism of eIF2α remains poorly understood in PAH rats. Here, we discover eIF2α is markedly upregulated in monocrotaline (MCT)-induced PAH rats, eIF2α can be upregulated by mRNA methylation, and upregulated eIF2α can promote PASMC proliferation in MCT-PAH rats. GSK2606414, eIF2α inhibitor, can downregulate the expression of eIF2α and alleviate PASMC proliferation in MCT-PAH rats. And we further discover the mRNA of eIF2α has a common sequence with N 6-methyladenosine (m6A) modification by bioinformatics analysis, and the expression of METTL3, WTAP, and YTHDF1 is upregulated in MCT-PAH rats. These findings suggest a potentially novel mechanism by which eIF2α is upregulated by m6A modification in MCT-PAH rats, which is involved in the pathogenesis of PAH.
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The viability of Zea mays seed plays a critical role in determining the yield of corn. Therefore, developing a fast and non-destructive method is essential for rapid and large-scale seed viability detection and is of great significance for agriculture, breeding, and germplasm preservation. In this study, hyperspectral imaging (HSI) technology was used to obtain images and spectral information of maize seeds with different aging stages. To reduce data input and improve model detection speed while obtaining more stable prediction results, successive projections algorithm (SPA) was used to extract key wavelengths that characterize seed viability, then key wavelength images of maize seed were divided into small blocks with 5 pixels ×5 pixels and fed into a multi-scale 3D convolutional neural network (3DCNN) for further optimizing the discrimination possibility of single-seed viability. The final discriminant result of single-seed viability was determined by comprehensively evaluating the result of all small blocks belonging to the same seed with the voting algorithm. The results showed that the multi-scale 3DCNN model achieved an accuracy of 90.67% for the discrimination of single-seed viability on the test set. Furthermore, an effort to reduce labor and avoid the misclassification caused by human subjective factors, a YOLOv7 model and a Mask R-CNN model were constructed respectively for germination judgment and bud length detection in this study, the result showed that mean average precision (mAP) of YOLOv7 model could reach 99.7%, and the determination coefficient of Mask R-CNN model was 0.98. Overall, this study provided a feasible solution for detecting maize seed viability using HSI technology and multi-scale 3DCNN, which was crucial for large-scale screening of viable seeds. This study provided theoretical support for improving planting quality and crop yield.
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Background: Chronic schizophrenia is significantly influenced by negative symptoms, with several known contributors to secondary negative symptoms. However, the impact of these factors and negative symptoms on social functioning warrants further exploration. Methods: We assessed the clinical symptoms, antipsychotic adverse reactions, and social functioning of 283 hospitalized patients with chronic schizophrenia using various standardized interviews and scales. We conducted multiple regression and mediation analyses to elucidate the impact of secondary factors on negative symptoms, and the relationship among these "secondary factors," negative symptoms, and social functioning. Results: Our findings identified depressive symptoms, extrapyramidal symptoms, and positive symptoms as significant contributors to secondary negative symptoms. We found that negative symptoms play a notable mediating role in the effect of depressive and positive symptoms on social functioning. However, the relationship between positive symptoms, negative symptoms, and social functioning proved to be intricate. Conclusion: Our findings propose that negative symptoms act as pivotal mediators in the correlation between "secondary factors" (including the depressive symptoms and positive symptoms) and social functioning. The treatment of chronic schizophrenia necessitates focusing on key factors such as depressive and positive symptoms, which might significantly contribute to the development of secondary negative symptoms. Further research is essential to clarify the complex relationship among positive symptoms, negative symptoms, and social functioning in schizophrenia.
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Hitherto, the intelligent detection of black tea fermentation quality is still a thought-provoking problem because of one-side sample information and poor model performance. This study proposed a novel method for the prediction of major chemical components including total catechins, soluble sugar and caffeine using hyperspectral imaging technology and electrical properties. The multielement fusion information were used to establish quantitative prediction models. The performance of model using multielement fusion information was better than that of model using single information. Subsequently, the stacking combination model using fusion data combined with feature selection algorithms for evaluating the fermentation quality of black tea. Our proposed strategy achieved better performance than classical linear and nonlinear algorithms, with the correlation coefficient of the prediction set (Rp) for total catechins, soluble sugar and caffeine being 0.9978, 0.9973 and 0.9560, respectively. The results demonstrated that our proposed strategy could effectively evaluate the fermentation quality of black tea.
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2-(2-Phenylethyl)chromones (PECs) are the main bioactive components of agarwood which showed diverse pharmaceutical activities. Glycosylation is a useful structural modification method to improve compounds' druggability. However, PEC glycosides were rarely reported in nature which largely limited their further medicinal investigations and applications. In this study, the enzymatic glycosylation of four naturally separated PECs 1-4 was achieved using a promiscuous glycosyltransferase UGT71BD1 identified from Cistanche tubulosa. It could accept UDP-Glucose, UDP-N-acetylglucosamine and UDP-xylose as sugar donors and conduct the corresponding O-glycosylation of 1-4 with high conversion efficiencies. Three O-glucosylated products 1a (5-hydroxy-2-(2-phenylethyl)chromone 8-O-ß-D-glucopyranoside), 2a (8-chloro-2-(2-phenylethyl)chromone 6-O-ß-D-glucopyranoside) and 3a (2-(2-phenylethyl)chromone 6-O-ß-D-glucopyranoside) were prepared and structurally elucidated as novel PEC glucosides based on NMR spectroscopic analyses. Subsequent pharmaceutical evaluation found that 1a showed remarkably improved cytotoxicity against HL-60 cells, whose cell inhibition rate was 19 times higher than that of its aglycon 1. The IC50 value of 1a was further determined to be 13.96 ± 1.10 µM, implying its potential as a promising antitumor-leading candidate. To improve the production of 1, docking, simulation and site-directed mutagenesis were performed. The important role of P15 in the glucosylation of PECs was discovered. Besides, a mutant K288A with a two-fold increased yield for 1a production was also afforded. This research reported the enzymatic glycosylation of PECs for the first time, and also provide an eco-friendly pathway for the alternative production of PEC glycosides for leading compounds discovery.
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Cromonas , Glicosídeos , Humanos , Cromonas/farmacologia , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Preparações Farmacêuticas , Catálise , Difosfato de Uridina , Estrutura MolecularRESUMO
BACKGROUND: Bruises caused by mechanical collision during the harvesting and storage and transportation period are difficult to detect using traditional machine vision technologies because there is no obvious difference in appearance between bruised and sound tissues. As a result of its fast and non-destructive characteristics, hyperspectral imaging technology is a potential tool for non-destructive detection of fruit surface defects. RESULTS: In the present study, visible near infrared hyperspectral reflectance images of healthy apples and bruised apples at 6, 12 and 24 h were obtained. To reduce hyperspectral data dimension, optimal wavelength selection algorithms including principal component analysis (PCA) and band ratio methods were utilized to select the effective wavelengths and enhance the contrast between bruised and sound tissues. Then pseudo-color image transformation technology combining with improved watershed segmentation algorithm (IWSA) were employed to recognize the bruise spots. The result obtained showed that band ratio images obtained better detection performance than that of PCA. The G component derived from pseudo-color image of λ 821 - λ 752 / λ 821 + λ 752 followed by IWSA obtained the best segmentation performance for bruise spots. Finally, a multispectral imaging system for the detection of bruised apple was developed to verify the effectiveness of the proposed two-band ratio algorithm, obtaining recognition rates of 93.3%, 92.2% and 92.5% for healthy, bruised and overall apples, respectively. CONCLUSION: The bruise detection algorithm proposed in the present study has potential to detect bruised apple in online practical applications and hyperspectral reflectance imaging offers a useful reference for the detection of surficial defects of fruit. © 2023 Society of Chemical Industry.
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Contusões , Malus , Humanos , Imageamento Hiperespectral , Frutas , AlgoritmosRESUMO
Objective: Schizophrenia is a debilitating mental disorder with a high disability rate that is characterized by negative symptoms such as apathy, hyperactivity, and anhedonia that can make daily life challenging and impair social functioning. In this study, we aim to investigate the effectiveness of homestyle rehabilitation in mitigating these negative symptoms and associated factors. Methods: A randomized controlled trial was conducted to compare the efficacy of hospital rehabilitation and homestyle rehabilitation for negative symptoms in 100 individuals diagnosed with schizophrenia. The participants were divided randomly into two groups, each persisting for 3 months. The primary outcome measures were the Scale for Assessment of Negative Symptoms (SANS) and Global Assessment of Functioning (GAF). The secondary outcome measures included the Positive Symptom Assessment Scale (SAPS), Calgary Schizophrenia Depression Scale (CDSS), Simpson-Angus Scale (SAS), and Abnormal Involuntary Movement Scale (AIMS). The trial aimed to compare the effectiveness of the two rehabilitation methods. Results: Homestyle rehabilitation for negative symptoms was found to be more effective than hospital rehabilitation, according to the changes in SANS (T = 2.07, p = 0.04). Further analysis using multiple regression indicated that improvements in depressive symptoms (T = 6.88, p < 0.001) and involuntary motor symptoms (T = 2.75, p = 0.007) were associated with a reduction in negative symptoms. Conclusion: Homestyle rehabilitation may have greater potential than hospital rehabilitation in improving negative symptoms, making it an effective rehabilitation model. Further research is necessary to investigate factors such as depressive symptoms and involuntary motor symptoms, which may be associated with the improvement of negative symptoms. Additionally, more attention should be given to addressing secondary negative symptoms in rehabilitation interventions.
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INTRODUCTION: Pancreatic cancer is highly fatal and its incidence is rising worldwide. Its poor prognosis is attributed to a lack of effective diagnostic and therapeutic strategies. Dihydrotanshinone I (DHT), a phenanthrene quinone liposoluble compound from Salvia miltiorrhiza Bunge (Danshen), exerts anti-tumor effects by inhibiting cell proliferation, enhancing apoptosis, and inducing cell differentiation. However, its effects on pancreatic cancer are unclear. > Methods: The role of DHT in the growth of tumor cells was explored using real-time cell analysis (RTCA), colony formation assay, and CCK-8. The effects of DHT on tumor cells invasion as well as migration were assessed by Transwell and migration assays. Expressions of pro-apoptosis and metastasis factors in tumor cells were examined using western blot. Tumor apoptosis rates were studied using flow cytometry. The anticancer effect of DHT in vivo was assessed by tumor transplantation into nude mice. RESULTS: Our analyses show that DHT has a suppressive role in epithelial-mesenchymal transition (EMT), invasiveness, proliferation, as well as migratory ability of Patu8988 and PANC-1 cells via Hedgehog/Gli signaling. Moreover, it drives apoptosis via caspases/BCL2/BAX signaling. Experiments in nude mice transplanted with tumors have shown DHT to have anticancer effects in vivo. > Conclusion: Our data show that DHT effectively suppresses pancreatic cancer cell proliferation as well as metastasis, and induces apoptosis via Hedgehog/Gli signaling. These effects have been reported to be dose- and time-dependent. Therefore, DHT can be exploited as a potential treatment for pancreatic cancer.>.
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Neoplasias Pancreáticas , Fenantrenos , Animais , Camundongos , Apoptose , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Proteínas Hedgehog/metabolismo , Camundongos Nus , Neoplasias Pancreáticas/patologia , Fenantrenos/farmacologia , Fenantrenos/uso terapêutico , Quinonas/farmacologia , Quinonas/uso terapêutico , Transdução de Sinais , Humanos , Neoplasias PancreáticasRESUMO
As a biocatalyst, enzyme has the advantages of high catalytic efficiency, strong reaction selectivity, specific target products, mild reaction conditions, and environmental friendliness, and serves as an important tool for the synthesis of complex organic molecules. With the continuous development of gene sequencing technology, molecular biology, genetic manipulation, and other technologies, the diversity of enzymes increases steadily and the reactions that can be catalyzed are also gradually diversified. In the process of enzyme-catalyzed synthesis, the majority of common enzymatic reactions can be achieved by single enzyme catalysis, while many complex reactions often require the participation of two or more enzymes. Therefore, the combination of multiple enzymes together to construct the multi-enzyme cascade reactions has become a research hotspot in the field of biochemistry. Nowadays, the biosynthetic pathways of more natural products with complex structures have been clarified, and secondary metabolic enzymes with novel catalytic activities have been identified, discovered, and combined in enzymatic synthesis of natural/unnatural molecules with diverse structures. This study summarized a series of examples of multi-enzyme-catalyzed cascades and highlighted the application of cascade catalysis methods in the synthesis of carbohydrates, nucleosides, flavonoids, terpenes, alkaloids, and chiral molecules. Furthermore, the existing problems and solutions of multi-enzyme-catalyzed cascade method were discussed, and the future development direction was prospected.
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Alcaloides , Produtos Biológicos , Produtos Biológicos/química , Catálise , BiocatáliseRESUMO
This article aims to studying how to solve dynamic Sylvester quaternion matrix equation (DSQME) using the neural dynamic method. In order to solve the DSQME, the complex representation method is first adopted to derive the equivalent dynamic Sylvester complex matrix equation (DSCME) from the DSQME. It is proven that the solution to the DSCME is the same as that of the DSQME in essence. Then, a state-of-the-art neural dynamic method is presented to generate a general dynamic-varying parameter zeroing neural network (DVPZNN) model with its global stability being guaranteed by the Lyapunov theory. Specifically, when the linear activation function is utilized in the DVPZNN model, the corresponding model [termed linear DVPZNN (LDVPZNN)] achieves finite-time convergence, and a time range is theoretically calculated. When the nonlinear power-sigmoid activation function is utilized in the DVPZNN model, the corresponding model [termed power-sigmoid DVPZNN (PSDVPZNN)] achieves the better convergence compared with the LDVPZNN model, which is proven in detail. Finally, three examples are presented to compare the solution performance of different neural models for the DSQME and the equivalent DSCME, and the results verify the correctness of the theories and the superiority of the proposed two DVPZNN models.
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BACKGROUND: Diacylglycerol (DAG)-enriched oil has been attracting attention because of its nutritional benefits and biological functions, although the composition of its various free fatty acids (FFAs) and an unclear relationship between substrate and yield make it difficult to be identified and qualified with respect to its production. In the present study, linoleic acid-enriched diacylglycerol (LA-DAG) was synthesized and enriched from Camellia oil by the esterification process using the combi-lipase Lipozyme TL IM/RM IM system. RESULTS: The relationship between FFA composition and DAG species productivity was revealed. The results showed that heterogeneous FFA with a major constituent (more than 50%) exhibited higher DAG productivity and inhibited triacylglycerol productivity compared to homogeneous constituents. Joint characterization by high-performance liquid chromatography-evaporative light scattering detection, gas chromatography-mass spectrometry and ultra-performance liquid chromatography-heated electrospray ionization-tandem mass spectrometry identified that DAG components contained dilinoleic acid acyl glyceride, linoleyl-oleyl glyceride and dioleic acid acyl glyceride in esterification products. Under the optimum conditions, 60.4% 1,3-DAG and 61.3% LA-DAG in the crude product at 1 h reaction were obtained, and further purified to 81.7% LA-DAG and 94.7% DAG via silica column chromatography. CONCLUSION: The present study provides a guideline for the identification of DAG species, as well as a structure-guided preparation method of DAG-enriched oils via the cost-effective combi-lipase. © 2022 Society of Chemical Industry.