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1.
J Hazard Mater ; 465: 133278, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38118199

ABSTRACT

Soil microplastics (MPs) have attracted widespread attention recently. Most studies have explored how soil MPs affect the soil's physicochemical parameters, matter circulation, and soil microbial community assembly. Similarly, a key concern in agricultural development has been the use of phosphorus (P) fertiliser, which is essential for plant health and development. However, the relationship between MPs and phosphate fertilisers and their effects on the soil environment and plant growth remains elusive. This study assessed the influence of adding low-density polyethylene MPs (1%) with different phosphate fertiliser application rates on microbial communities and rice biomass. Our results showed that MPs changed the structure of soil bacterial and phoD-harbouring microbial communities in the treatment with P fertiliser at the same level and suppressed the interactions of phoD-harbouring microorganisms. In addition, we found that MPs contamination inhibited rice growth; however, the inclusion of P fertiliser in MP-contaminated soils reduced the inhibitory action of MPs on rice growth, probably because the presence with P fertiliser promoted the uptake of NO3--N by rice in MP-contaminated soils. Our results provide further insights into guiding agricultural production, improving agricultural management, and rationally applying phosphate fertilisers in the context of widespread MPs pollution and global P resource constraints.


Subject(s)
Oryza , Soil , Soil/chemistry , Microplastics , Plastics , Fertilizers/analysis , Oryza/microbiology , Phosphorus , Phosphates
2.
Front Microbiol ; 14: 1292959, 2023.
Article in English | MEDLINE | ID: mdl-38029118

ABSTRACT

Biochar as an agricultural soil amendment plays vital roles in mediating methane (CH4) and nitrous oxide (N2O) emissions in soils. The link between different types of biochar, bulk soil, and rhizosphere microbial communities in relation to CH4 and N2O emissions is being investigated in this study. The rice pot experiment was conducted using biochar at two temperatures (300°C and 500°C) in combination with three biochar levels (0, 2, 10% w/w). Soil properties and the abundance of genes associated with CH4 and N2O emissions from both rhizosphere and bulk soils were investigated. The study also aimed to examine the structure of microbial communities (pmoA, nosZ) in rhizosphere and bulk soils whereas CH4 and N2O emissions were monitored while growing rice. Results showed that biochar at 300°C and 10% incorporation significantly increased the CH4 emissions by up to 59% rise compared to the control group. Random Forest analysis revealed that the ratio of mcrA/pmoA along with the abundance of mcrA from both rhizosphere and bulk soils, the abundance of AOA, TN, DOC, and the community composition of pmoA-harboring microorganisms from both bulk and rhizosphere soils were important predictors of CH4 emissions. Therefore, the ratio of mcrA/pmoA in rhizosphere soil and the abundance of AOA in bulk soil were the main factors influencing CH4 emissions. Variation Partitioning Analysis (VPA) results indicated that the effects of these factors on bulk soil were 9% of CH4 emissions variations in different treatments, which contributed more than rhizosphere soils' factors. Moreover, random forest analysis results indicated that the abundance of AOB in bulk soil was the most important predictor influencing N2O emissions. The VPA result revealed that the factors in rhizosphere soil could explain more than 28% of the variations in N2O emissions. Our study highlights that rhizosphere soil has a more significant effect than bulk soil on N2O production. Our findings further the understanding of the link between bulk and rhizosphere attributes, and their impact on CH4 and N2O emissions in paddy soils. In summary, we recommend the application of biochar at 500°C and 2% incorporation rate for agricultural production in the area.

3.
Zhongguo Gu Shang ; 36(4): 381-5, 2023 Apr 25.
Article in Chinese | MEDLINE | ID: mdl-37087630

ABSTRACT

OBJECTIVE: To observe clinical effect of percutaneous minimally invasive osteotomy with 8-shaped bandage and hallux valgus splint fixation in treating moderate hallux valgus. METHODS: Totally 23 patients with moderate hallux valgus were treated with percutaneous minimally invasive osteotomy with 8-shaped bandage and hallux valgus splint fixation from August 2019 to January 2021, and 1 patient was loss to follow-up, and finally 22 patients(30 feet) were included, 4 males (6 feet) and 18 females(24 feet), aged from 27 to 66 years old with an average of(50.59±11.95) years old. Hallux valgus angle (HVA), intermetatarsal angle (IMA), metatarsal span (the distance between the first and the fifth metatarsal bones), changed of soft tissue width, American Orthopaedic Foot and Ankle Society(AOFAS) score, and Visual Analogue Scale (VAS) were collected and compared before operation and 6 months after operation. RESULTS: Twenty-two patients were followed up from 5.7 to 6.4 months with an average of (6.13±0.85) months. The first metatarsal osteotomy of patients were obtained bone union, and deformity of the toes was corrected. Complications such as avascular necrosis of metatarsal head and transfer metatarsalgia were not occurred. Postoperative HVA, IMA, metatarsal span, soft tissue width, VAS, AOFAS score at 6 months were significantly improved compared with pre-operation (P<0.01). According to AOFAS score at 6 months after operation, 10 feet were excellent, 18 good and 2 poor. Two feet with poor were excellent after prolonged 8-shaped bandage and hallux valgus splint fixation time. CONCLUSION: Percutaneous minimally invasive osteotomy with 8-shaped bandage and hallux valgus splint fixation for the treatment of moderate hallux valgus could better correct deformity of hallux valgus, relieve foot symptoms, good recovery of postoperative function, and has a significant clinical efficacy.


Subject(s)
Bunion , Hallux Valgus , Metatarsal Bones , Male , Female , Humans , Adult , Middle Aged , Aged , Hallux Valgus/surgery , Hallux Valgus/diagnostic imaging , Splints , Radiography , Treatment Outcome , Metatarsal Bones/surgery , Osteotomy , Bandages
4.
J Immunother Cancer ; 11(2)2023 02.
Article in English | MEDLINE | ID: mdl-36759015

ABSTRACT

BACKGROUND: Tertiary lymphoid structures (TLSs) have been proposed to assess the prognosis of patients with cancer. Here, we investigated the prognostic value and relevant mechanisms of TLSs in colorectal cancer liver metastases (CRCLM). METHODS: 603 patients with CRCLM treated by surgical resection from three cancer centers were included. The TLSs were categorized according to their anatomic subregions and quantified, and a TLS scoring system was established for intratumor region (T score) and peritumor region (P score). Differences in relapse-free survival (RFS) and overall survival (OS) between groups were determined. Multiplex immunohistochemical staining (mIHC) was used to determine the cellular composition of TLSs in 40 CRCLM patients. RESULTS: T score positively correlated with superior prognosis, while P score negatively associated with poor survival (all p<0.05). Meanwhile, T score was positively associated with specific mutation subtype of KRAS. Furthermore, TLSs enrichment gene expression was significantly associated with survival and transcriptomic subtypes of CRCLM. Subsequently, mIHC showed that the densities of Treg cells, M2 macrophages and Tfh cells were significantly higher in intratumor TLSs than in peritumor TLSs (p=0.029, p=0.047 and p=0.041, respectively), and the frequencies of Treg cells and M2 macrophages were positively correlated with P score, while the frequencies of Tfh cells were positively associated with T scores in intratumor TLSs (all p<0.05). Next, based on the distribution and abundance of TLSs, an Immune Score combining T score and P score was established which categorized CRCLM patients into four immune classes with different prognosis (all p<0.05). Among them, patients with higher immune class have more favorable prognoses. The C-index of Immune Class for RFS and OS was higher than Clinical Risk Score statistically. These results were also confirmed by the other two validation cohorts. CONCLUSIONS: The distribution and abundance of TLSs is significantly associated with RFS and OS of CRCLM patients, and a novel immune class was proposed for predicting the prognosis of CRCLM patients.


Subject(s)
Colorectal Neoplasms , Liver Neoplasms , Tertiary Lymphoid Structures , Humans , Lymphocytes, Tumor-Infiltrating , Neoplasm Recurrence, Local/pathology , Liver Neoplasms/pathology , Colorectal Neoplasms/pathology
5.
Int J Colorectal Dis ; 38(1): 19, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36658235

ABSTRACT

PURPOSE: This study aimed to explore the prognostic significance of clinicopathological characteristics in early-onset versus late-onset colorectal liver metastases (CRLM). METHODS: The data of CRLM patients who underwent hepatectomy from September 2010 to September 2020 were retrospectively analyzed. According to the age of primary cancer diagnosis, patients were divided into early-onset CRLM (EOCRLM) and late-onset CRLM (LOCRLM) groups. Clinicopathological parameters were compared between the two groups. Cox regression model and Kaplan-Meier method were used to analyze the effect of clinicopathological parameters on overall survival (OS) and recurrence-free survival (RFS). RESULTS: In total, 431 CRLM patients were identified, 130 with EOCRLM and 301 with LOCRLM. Compared with LOCRLM patients, EOCRLM patients had lower American Society of Anesthesia (ASA) grade and longer operation time (204 vs. 179 min). More aggressive features were presented in EOCRLM patients including synchronous liver metastases (76.9% vs. 61.1%) and bilobar involvement (43.8% vs. 33.2%). No significant difference in OS or RFS was found between the two groups. Multivariate analysis of EOCRLM group showed that preoperative CA19-9 level and RAS/BRAF status were predictive of OS, while bilobar involvement and preoperative CEA level were associated with RFS. In LOCRLM group, the number of CRLM, preoperative CA19-9 level, and BRAF status were associated with OS, while the number of CRLM was associated with RFS. CONCLUSIONS: The preoperative CA19-9 level, RAS/BRAF status, bilobar involvement, and preoperative CEA level were predictive of EOCRLM patient prognosis, while the number of CRLM, preoperative CA19-9 level, and BRAF status were predictive of LOCRLM patient prognosis.


Subject(s)
Colorectal Neoplasms , Liver Neoplasms , Humans , Prognosis , CA-19-9 Antigen , Proto-Oncogene Proteins B-raf , Retrospective Studies , Colorectal Neoplasms/surgery , Liver Neoplasms/secondary , Hepatectomy
6.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-992724

ABSTRACT

Objective:To compare the clinical efficacy between reservation and sacrifice of remnants in the footprint area in arthroscopic repair of rotator cuff tear.Methods:A retrospective study was conducted to analyze the clinical data of 32 patients with rotator cuff tear plus remnants in the footprint area (2 cm < tear size <5 cm) who had been admitted to Department of Sports Medicine, The People's Hospital of Northern Jiangsu from May 2020 to July 2021. The patients were divided into 2 groups according to reservation or sacrifice of remnants in the footprint area in arthroscopic repair of rotator cuff tear. In the remnant-reservation group (16 cases): 5 males and 11 females with an age of (61.8±9.9) years, 9 left and 7 right shoulders affected, and (3.7±1.1) cm in size of rotator cuff tear; in the remnant-sacrifice group (16 cases): 4 males and 12 females with an age of (61.3±8.8) years, 8 left and 8 right shoulders affected, and (3.9±0.9) cm in size of rotator cuff tear. The 2 groups were compared in terms of visual analogue scale (VAS), American Shoulder and Elbow Surgeons (ASES) score, Constant-Murley shoulder function score (Constant score), and range of motion of the affected shoulder before surgery, 3 months after surgery and at the last follow-up. The ratio of bilateral abductor muscle strengths (affected side/healthy side) was analyzed and compared between the 2 groups, and the healing of the rotator cuff was evaluated by MRI at the last follow-up.Results:The 2 groups were comparable because there were no significant differences in all their preoperative demographic data ( P>0.05). The 32 patients were followed up for (14.3±3.5) months after surgery. At 3 months after surgery, the VAS score in the remnant-reservation group [1.0 (0.0,1.0) point] was significantly lower than that in the remnant-sacrifice group [1.0 (1.0,1.0) point] ( P<0.05), but there was no significant difference between the 2 groups in ASES score, Constant score or range of motion of the affected shoulder ( P>0.05). At the last follow-up, the ASES score, forward flexion, abduction and ratio of bilateral abductor muscle strengths (affected side/healthy side) in the remnant-reservation group [(96.1±4.8) points, 170.0 (170.0,170.0)°, 160.0 (160.0,170.0)°, and 85.5%±13.8%]were significantly better than those in the remnant-sacrifice group [(91.4±5.9) points, 160.0 (160.0,170.0)°, 150.0 (140.0,155.0)°, and 72.6%±16.9%] ( P < 0.05), but there were no statistically significant differences between the 2 groups in VAS score, Constant score, neutral external rotation angle, or body-side internal rotation ( P>0.05). The Sugaya grading for MRI rotator cuff healing was significantly different between the 2 groups at the last follow-up ( P<0.05). Conclusion:In arthroscopic repair of rotator cuff tear, reservation of remnants in the footprint area can significantly relieve postoperative shoulder pain, and has obvious advantages in restoration of shoulder forward flexion, abduction and abductor muscle strength, leading to better healing of the rotator cuff and the large nodule than the remnant-sacrifice technique.

7.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-991141

ABSTRACT

The development of chemoresistance which results in a poor prognosis often renders current treatments for colorectal cancer(CRC).In this study,we identified reduced microvessel density(MVD)and vascular immaturity resulting from endothelial apoptosis as therapeutic targets for overcoming chemoresistance.We focused on the effect of metformin on MVD,vascular maturity,and endothelial apoptosis of CRCs with a non-angiogenic phenotype,and further investigated its effect in overcoming chemoresistance.In situ transplanted cancer models were established to compare MVD,endothelial apoptosis and vascular maturity,and function in tumors from metformin-and vehicle-treated mice.An in vitro co-culture system was used to observe the effects of metformin on tumor cell-induced endothelial apoptosis.Transcriptome sequencing was performed for genetic screening.Non-angiogenic CRC developed inde-pendently of angiogenesis and was characterized by vascular leakage,immaturity,reduced MVD,and non-hypoxia.This phenomenon had also been observed in human CRC.Furthermore,non-angiogenic CRCs showed a worse response to chemotherapeutic drugs in vivo than in vitro.By suppressing endo-thelial apoptosis,metformin sensitized non-angiogenic CRCs to chemo-drugs via elevation of MVD and improvement of vascular maturity.Further results showed that endothelial apoptosis was induced by tumor cells via activation of caspase signaling,which was abrogated by metformin administration.These findings provide pre-clinical evidence for the involvement of endothelial apoptosis and subsequent vascular immaturity in the chemoresistance of non-angiogenic CRC.By suppressing endothelial apoptosis,metformin restores vascular maturity and function and sensitizes CRC to chemotherapeutic drugs via a vascular mechanism.

8.
Acta Pharmaceutica Sinica ; (12): 1103-1116, 2023.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-978689

ABSTRACT

The incidence of thrombosis-induced cardiovascular diseases is increasing worldwide and poses a serious threat to human health. Three factors, slow speed of blood flow, hypercoagulable blood and vascular damage, have been considered to be causes of thrombosis. Antithrombotic drugs have been classified into three categories based on the mechanism of thrombosis, including anticoagulants, platelet inhibitors and fibrinolytics. The coagulation and anticoagulation systems have drawn increasing attention because of the important role they play in the process of thrombosis. Novel compounds with anticoagulant activity are now emerging, alleviating to some extent some of the problems associated with the clinical use of early approved thrombotic drugs, such as high bleeding risk, slow onset of action and narrow therapeutic windows. In this review, we initially describe the mechanisms of coagulation as well as thrombosis. Meanwhile, a wide range of bioactive compounds and potential antithrombotic candidates reported in recent years have been summarized. In addition, the structure-activity relationship of certain compounds has been discussed, expecting to facilitate the development of molecules with anticoagulant biological activity for the treatment of thrombotic diseases.

9.
Article in English | WPRIM (Western Pacific) | ID: wpr-982401

ABSTRACT

Wax apple (Syzygium samarangense) has received growing research interest for its high nutritional and medicinal value due to its constituents such as polysaccharide, organic acids, flavonoids, minerals, and other substances. In this study, wax apple polysaccharide (WAP) was isolated from this plant and its protective effect against ethyl carbamate (EC)‍-induced oxidative damage was evaluated in human hepatocytes (L02 cells). Firstly, a series of analyses such as high-performance liquid chromatography (HPLC), high-performance gel permeation chromatography (HPGPC), Fourier transform infrared spectroscopy (FT-IR), gas chromatography/mass spectrometry (GC/MS), and 1H and 13C nuclear magnetic resonance (NMR) were conducted to identify the structure of WAP. Thereafter, in vitro cell experiments were performed to verify the protective effects of WAP against EC-induced cytotoxicity, genotoxicity, and oxidative damage in L02 cells. Our results revealed that WAP is composed of mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, arabinose, and fucose in a molar ratio of 2.20:‍3.94:‍4.45:‍8.56:‍8.86:‍30.82:‍39.78:‍1.48. Using a combination of methylation and NMR spectroscopic analysis, the primary structure of WAP was identified as Araf-(1→, Glcp-(1→, →2)‍-Araf-(1→, →3)‍-Galp-(1→, →3)‍-Araf-‍(1→, and →6)‍-Galp-‍(1→. Cell experiments indicated that WAP exhibited significant protective effects on EC-treated L02 cells via suppressing cytotoxicity and genotoxicity, reducing reactive oxygen species (ROS) and O2•- formation, as well as improving mitochondrial membrane potential (MMP) and glutathione (GSH). In a nutshell, WAP has the potential as an important therapeutic agent or supplement for hepatic oxidative damage. Meanwhile, further studies are needed to prove the above effects in vivo at the biological and clinical levels.


Subject(s)
Humans , Syzygium/chemistry , Urethane/pharmacology , Spectroscopy, Fourier Transform Infrared , Oxidative Stress , Glutathione/pharmacology , Hepatocytes , Polysaccharides/pharmacology
10.
PLoS One ; 17(8): e0271759, 2022.
Article in English | MEDLINE | ID: mdl-35930563

ABSTRACT

OBJECTIVE: To explore the relationship between physical activity and prosocial behavior in college students, and to examine whether self-perception and gender may play mediating and moderating roles, respectively, in that relationship. METHODS: The International Physical Activity Questionnaire-long form, Prosocial Tendencies Measure, and Self-perception Scale were used to survey 647 college students in Yangzhou, China. Internal consistency testing, one-way analyses of variance (ANOVAs) across physical activity levels, exploratory factor analysis, correlation testing, mediation effect testing (independent variable, physical activity; mediating variable, self-perception; dependent variable, prosocial behavior), bootstrap testing and moderated mediation testing were conducted. RESULTS: Physical activity level was not found to be a direct predictor prosocial behavior in college students. Self-perception was found to play a mediating role between physical activity and prosocial behavior. CONCLUSION: Physical activity is not directly predictive college students' prosocial behavior tendencies, but it is indirectly predictive through self-perception. This study explores the relationship between the three variables and the path of the relationship, deepening the research related to the relationship between physical activity and prosocial behavior, providing ideas for fostering prosocial behavior in Chinese universities, as well as providing a theoretical basis for possible future empirical research.


Subject(s)
Altruism , Students , Exercise , Humans , Self Concept , Universities
11.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-991105

ABSTRACT

In this study,ecofriendly and economic carboxy-terminated plant fibers(PFs)were used as adsorbents for the effective in-syringe solid phase extraction(IS-SPE)of fluoroquinolone(FQ)residues from water.Based on the thermal esterification and etherification reaction of cellulose hydroxy with citric acid(CA)and sodium chloroacetate in aqueous solutions,carboxy groups grafted onto cotton,cattail,and corncob fibers were fabricated.Compared with carboxy-terminated corncob and cotton,CA-modified cattail with more carboxy groups showed excellent adsorption capacity for FQs.The modified cattail fibers were reproducible and reusable with relative standard deviations of 3.2%-4.2%within 10 cycles of adsorption-desorption.A good extraction efficiency of 71.3%-80.9%was achieved after optimizing the extraction condition.Based on carboxylated cattail,IS-SPE coupled with ultra-performance liquid chromatography with a photodiode array detector was conducted to analyze FQs in environmental water samples.High sensitivity with limit of detections of 0.08-0.25 μg/L and good accuracy with recoveries of 83.8%—111.7%were obtained.Overall,the simple and environment-friendly modified waste PFs have potential appli-cations in the effective extraction and detection of FQs in natural waters.

12.
Chinese Journal of Pediatrics ; (12): 227-231, 2022.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-935675

ABSTRACT

Objective: To investigate the clinical features, pathological phenotype, treatment and prognosis of Castleman's disease in children. Methods: Clinical data of 15 children diagnosed with Castleman's disease in Henan Provincial People's Hospital and the First Affiliated Hospital of Zhengzhou University from May 2010 to October 2019 were analyzed retrospectively. The clinical characteristics, laboratory examination and histopathological data were analyzed. Results: Among the 15 Castleman's disease patients, 12 were males and 3 females. The age of first visit was 12 (10, 15) years. The time from mass discovery to pathologic diagnosis was 9.0 (2.0, 13.0) months. The majority of patients were unicentric (13 cases), and the histopathological type was hyaline vascular (11 cases). Unicentric lesions were most common in the neck (11 cases), all 13 patients received complete surgical resection of the lesions, the follow-up time was 20.0 (13.5, 50.5) months, and the prognosis was good. Two cases were multicentric type, the pathological types were mixed variant, meeting the criteria of idiopathic Castleman's disease, the two children underwent partial surgical resection, one was treated with rituximab and prednisone and the other was treated with thalidomide and prednisone. The follow-up time was 32 months and 10 month, both of them had good prognosis. Conclusions: Most cases of Castleman's disease in children are diagnosed late, and the unicentric type is dominant. The most common pathological type is hyaline vascular, which is characterized by painless lymphadenopathy, while multicentric type has systemic symptoms and both of them have a good overall prognosis.


Subject(s)
Female , Humans , Male , Castleman Disease/therapy , Neck/pathology , Prognosis , Retrospective Studies , Rituximab
14.
Article in English | WPRIM (Western Pacific) | ID: wpr-880746

ABSTRACT

OBJECTIVES@#To evaluate the composition of bioactive substances and the antioxidant effects of jujube fruit under gut microbiota fermentation (GMF), and the inhibitory effect on cytotoxicity caused by ethyl carbamate (EC).@*METHODS@#Changes in the contents of flavonoids, polyphenols, total sugars, and reducing sugars of jujube fruit after GMF (0, 2, 6, 12, 24, and 48 h) were determined. The oxidation resistance of fermented jujube fruits (from 0 to 48 h fermentation) was evaluated using in vitro 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) and ferric reducing antioxidant power (FRAP) assays. Inhibitory effects of 48 h-fermented jujube fruit at various concentrations (0.25, 0.50, 1.00, and 2.00 mg/mL) on EC-treated toxicity and DNA damage of Caco-2 cells were estimated using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and nuclear staining assays, respectively. Effects of different concentrations of jujube fruit on EC-treated Caco-2 cells' intracellular reactive oxygen species (ROS), glutathione (GSH) levels, and mitochondrial membrane potential (MMP) were also evaluated.@*RESULTS@#Jujube fruit has rich bioactive components after GMF and shows strong antioxidant capacity. Fermented jujube fruit can inhibit the cytotoxicity and DNA damage of Caco-2 cells caused by EC and reduce intracellular ROS generation, as well as restoring GSH and MMP.@*CONCLUSIONS@#Fermented jujube fruit extracts produced by GMF still contain biologically active substances which retain biological activity and antioxidation capabilities.

15.
Org Biomol Chem ; 18(45): 9317, 2020 Nov 25.
Article in English | MEDLINE | ID: mdl-33179697

ABSTRACT

Correction for 'N-Primary-amine tetrapeptide-catalyzed highly asymmetric Michael addition of aliphatic aldehydes to maleimides' by Zhi-Hong Du et al., Org. Biomol. Chem., 2020, 18, 6899-6904, DOI: 10.1039/D0OB01457E.

16.
Org Biomol Chem ; 18(35): 6899-6904, 2020 09 21.
Article in English | MEDLINE | ID: mdl-32856662

ABSTRACT

The highly asymmetric Michael addition reaction between maleimides and aliphatic aldehydes catalyzed by low-loading ß-turn tetrapeptides with excellent yields and enantioselectivities at room temperature was reported. α-Branched and α-unbranched aldehydes both are suitable nucleophiles. N-Aryl, alkyl and hydrogen maleimides all are well tolerated and led to high yields and enantioselectivities. The transformation can be enlarged to the gram scale without decrease in the yield and enantioselectivity. Furthermore, the succinimides were converted into γ-lactams and γ-lactones, showing good practicality of this work. Some reaction intermediates in the proposed reaction mechanism can be captured with the HR-MS method.


Subject(s)
Maleimides
17.
Polymers (Basel) ; 12(7)2020 Jun 30.
Article in English | MEDLINE | ID: mdl-32629774

ABSTRACT

The mechanical stability of aqueous binder and conductive composites (BCC) is the basis of the long-term service of composite electrodes in advanced secondary batteries. To evaluate the stress evolution of BCC in composite electrodes during electrochemical operation, we established an electrochemical-mechanical model for multilayer spherical particles that consists of an active material and a solid-electrolyte-interface (SEI)-enclosed BCC. The lithium-diffusion-induced stress distribution was studied in detail by coupling the influence of SEI and the viscoelasticity of inorganic-filler-doped polymeric bonding material. It was found that tensile hoop stress plays a critical role in determining whether a composite electrode is damaged or not-and circumferential cracks may primarily initiate in BCC, rather than in other electrode components. Further, the peak tensile stress of BCC is at the interface with SEI and does not occur at full lithiation due to the relaxation nature of polymer composite. Moreover, mechanical damage would be greatly misled if neglecting the existence of SEI. Finally, the structure integrity of the binder and conductive system can be effectively improved by (1) increasing the carbon black content as much as possible in the context of meeting cell capacity requirements-it is greater than 27% and 50% for sodium alginate and the mixtures of carboxy styrene butadiene latex and sodium carboxymethyl cellulose, respectively, for composite graphite anode; (2) reducing the elastic modulus of SEI to less than that of BCC; (3) decreasing the lithiation rate.

18.
Org Lett ; 22(11): 4444-4450, 2020 06 05.
Article in English | MEDLINE | ID: mdl-32463241

ABSTRACT

ß-Turn tetrapeptides were demonstrated to catalyze asymmetric aldol reaction of α-branched aldehydes and α-carbonyl aldehydes, i.e. glyoxylates and α-ketoaldehydes, to biomimetically synthesize acyclic all-carbon quaternary center-bearing 1,4-dicarbonyls in high yield and excellent enantioselectivity under mild conditions. The spatially restricted environment of the tetrapeptide warrants high enantioselectivity and yield with broad substrates. Using this protocol, (R)-pantolactone, the key intermediate of vitamin B5, was readily accessed in a practical, efficient, and environmentally benign process from inexpensive starting materials.


Subject(s)
Aldehydes/chemistry , Ketones/chemical synthesis , Peptides/chemistry , Catalysis , Crystallography, X-Ray , Ketones/chemistry , Models, Molecular , Molecular Structure
19.
Polymers (Basel) ; 11(9)2019 Sep 14.
Article in English | MEDLINE | ID: mdl-31540090

ABSTRACT

To predict the cyclic stability of secondary battery electrodes, the mechanical behaviors of polymer binders and conductive composites (BCC) is of great significance. In terms of uniaxial tension, tensile stress relaxation, and bonding strength tests, the present study encompasses a systematic investigation of the mechanical properties of two typical aqueous binders with different contents of Super-S carbon black (SS) under a liquid electrolyte. Meanwhile, the microstructure of cured film and the surface morphology of the bonding interface are investigated in detail. When the weight ratio of SS increases from 0% to 50%, the cured BCC films manifest a higher ratio of tensile strength to modulus and a shorter characteristic relaxation time. Moreover, suitable loadings of SS can improve the tensile shear strength and remarkably reduce the percentage of interface failure of aqueous polymer-bonded Cu current collector. Nevertheless, an excess of carbon black amount cannot maintain its enhancing effect and can even impair the adhesive layer. Finally, a sodium alginate-based polymer composite holds much more superior mechanical properties than the mixture of sodium carboxymethyl cellulose and styrene-butadiene rubber at the same content of carbon black. Noticeably, the two kinds of aqueous polymer doped by 50 wt % of SS exhibit the best adhesive properties.

20.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-254406

ABSTRACT

Celiac trunk is a wide and short ventral branch. It originates from the anterior abdominal artery at the level of L1 vertebra, and divides into three branches: the left gastric, common hepatic and splenic arteries, supplying the upper abdominal organs such as stomach, liver, spleen, pancreas, and duodenum. However, there are many types of branches variations. The branches of celiac trunk are classified into several types. We establish a classification of variation type according to the origin of left gastric, common hepatic and splenic arteries, which includes hepatogastrosplenic trunk type, hepatosplenic trunk type, hepatogastric trunk type, gastrosplenic trunk type, and the others include hepatosplenomesentery trunk type, hepatogastrospleno-mesentery trunk type, hepatogastrosplenocolonic trunk type, hepatogastrosplenopancreatic trunk type, gastrospenic trunk plus hepatomesentery trunk type, hepatogastrosplenoic left liver trunk type, hepatogastro-splenopancreatoduodenal trunk type, hepatogastric trunk plus hepatosplenic trunk type. Development of celiac trunk variation type was introduced based on the classification of Lipshutz, Adachi, Michels and Zhang Nianjia. Mastering the types of branches variations is necessary for us to perform the upper abdominal operations safely and effectively.


Subject(s)
Humans , Celiac Artery , Congenital Abnormalities
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