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High temperature treatment induced production of unreduced 2n pollen in Camellia oleifera

Horticultural Plant Journal 2024年第3期10卷 879-896页

作者： Hongda Deng Xiaoyu Zhang song sheng Yuxun Huang Ziqi Ye Tongyue Zhang Xing Liu Zhiqiang Han The Laboratory of Forestry Genetics Central South University of Forestry and TechnologyChangshaHunan 410004China Yuelushan Laboratory ChangshaHunan 410128China Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees of Ministry of Education Central South University of Forestry and TechnologyChangshaHunan 410004China National Forest and Seedling Workstation of Hunan Province The Forestry Department of Hunan ProvinceChangshaHunan 410004China

Unreduced gametes through chromosome doubling play a major role in the process of plant polyploidization.Our previous work confirmed that Camellia oleifera can produce natural 2n pollen,and it is possible to induce the 2n pollen formation by high temperature treatment.This study focused on the optimization of the 2n pollen induction technique and the mechanisms of high temperature-induced2n pollen formation in C.oleifera.We found that the optimal protocol for inducing 2n pollen via high temperature was to perform 45℃with4 h at the prophaseⅠstage of the pollen mother cells(PMCs).Meanwhile,high temperature significantly decreased the yield and fertility of2n pollen.Through the observation of meiosis,abnormal chromosome and cytological behaviour was discovered under high-temperature treatment,and we confirmed that the formation of 2n pollen is caused by abnormal cell plate.Based on weighted gene co-expression network analysis,fifteen hub genes related to cell cycle control were identified.After male flower buds were exposed to heat shock,polygalacturonase gene(CoPGX3)was significantly upregulated.We inferred that high temperature causes the CoPGX3 gene to be overexpressed and that CoPGX3 is redistributed into the cytosol where it degrades cytoplasmic pectin,which leads to an abnormal cell plate.Furthermore,abnormal cytokinesis resulted in the formation of dyads and triads,and PMCs divided to produce 2n pollen.Our findings provide new insights into the mechanism of 2n pollen induced by high temperature in a woody plant and lay a foundation for further ploidy breeding of C.oleifera.

关键词： Camellia oleifera Pollen mother cells(PMCs) High temperature Meiosis 2n pollen CoPGX3

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The Current State and Progress of Mpox Vaccine Research

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China CDC weekly 2024年第7期6卷 118-125页

作者： Xinlong Wang Zhixia Gu Shugui sheng Rui song Ronghua Jin Beijing Key Laboratory of Emerging Infectious Diseases Institute of Infectious DiseasesBeijing Ditan HospitalCapital Medical UniversityBeijingChina National Center for Infectious Diseases Beijing Ditan HospitalCapital Medical UniversityBeijingChina

On July 23,2022,the World Health Organization(WHO)declared the monkeypox(mpox)outbreak a“Public Health Emergency of International Concern.”Since 2022,outbreaks of mpox in many countries around the world have primarily resulted in fatalities among immunocompromised individuals,such as untreated HIV/AIDS patients.Since the eradication of smallpox was declared by the WHO in 1980,the global vaccination against smallpox has been gradually discontinued.China also stopped routine smallpox vaccination in 1981.The protective effect of the smallpox vaccine has decreased over time due to aging and declining immunity in those who were vaccinated.For individuals,timely vaccination against smallpox is an effective means of protection against mpox.However,due to safety concerns with the smallpox vaccine and the limitations of current mpox vaccines,there is no vaccine that is safe,effective,and has low side effects applied in clinical settings.This article provides a comprehensive review of the development of mpox virus(MPXV)vaccines,their application in special populations,and the current state of vaccine research,considering the etiology,transmission,and prevention of the MPXV.Vaccination,as an effective method of epidemic prevention,can provide long-term immune protection and effectively reduce the severity of infection.However,as there is no licensed specific MPXV vaccine available globally,the vaccines currently used for mpox prevention are mostly smallpox vaccines.These smallpox vaccines can offer some degree of protection against mpox by activating cross-protection in the body.

关键词： prevention routine protective

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Efficient capture of difluorocarbene by pyridinium 1,4-zwitterionic thiolates:A concise synthesis of difluoromethylene-containing 1,4-thiazine derivatives

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Chinese Chemical Letters 2024年第4期35卷 367-370页

作者： Zhiwei Chen Heyun sheng Xue Li Menghan Chen Xin Li Qiuling song Institute of Next Generation Matter Transformation College of Materials Science&Engineering and College of Chemical Engineering at Huaqiao UniversityXiamen 361021China Fujian University Key Laboratory of Molecule Synthesis and Function Discovery College of ChemistryFuzhou UniversityFuzhou 350108China State Key Laboratory of Organometallic Chemistry and Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

A practical method for the construction of difluoromethylene-containing 1,4-thiazine moieties using readily available diethyl bromodifluoromethanephosphonate(BrCF_(2)PO(OEt)_(2))as difluorocarbene precusor has been developed.This transformation features the efficient capture of difluorocarbene by pyridinium 1,4-zwitterionic thiolates.A series of structurally novel and functionalized difluoromethylene-containing 1,4-thiazine derivatives were thus synthesized in good yields.

关键词： Difluoromethylene Pyridinium 1 4-zwitterionic thiolates 1 4-Thiazine derivatives

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Distribution and geochemical significance of alkylbenzenes for crude oil with different depositional environments and thermal maturities

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Petroleum Science 2024年第2期21卷 777-790页

作者： Bing-Kun Meng Dao-Fu song Yuan Chen sheng-Bao Shi School of Petroleum Engineering and Environmental Engineering Yan©an UniversityYan©an716000ShaanxiChina State Key Laboratory of Petroleum Resources and Prospecting College of GeosciencesChina University of PetroleumBeijing102249China

A total of 45 alkylbenzenes were detected and identified in crude oils with different depositional environments and thermal maturities from the Tarim Basin,Beibuwan Basin,and songliao Basin using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry(GC×GCTOFMS).By analyzing the distribution characteristics of C0-C5alkylbenzenes,it is found that the content of some alkylbenzenes varies greatly in crude oils.Based on the distribution characteristics of 1,2,4,5-tetramethylbenzene(Te MB)and 1,2,3,4-Te MB,the ratio of 1,2,4,5-Te MB to 1,2,3,4-Te MB is proposed to indicate the organic matter origin and depositional environment of ancient sediments.Oil samples originated mainly from lower hydrobiont,algae,bacteria and source rocks deposited under reducing/anoxic conditions have low 1,2,4,5-/1,2,3,4-Te MB values(less than 0.6),while oil samples originated mainly from terrestrial higher plants and source rocks deposited under oxic/sub-oxic conditions have higher 1,2,4,5-/1,2,3,4-Te MB values(greater than 1.0).The significant difference of 1,2,4,5-/1,2,3,4-Te MB values is controlled by 1,2,4,5-Te MB content.1,2,4,5-Te MB content in oils derived from source rocks deposited in oxidized sedimentary environment(greater than 1.0 mg/g whole oil)is higher than that in oils from source rocks deposited in reduced sedimentary environment(less than 1.0 mg/g whole oil).1,2,4,5-/1,2,3,4-Te MB ratio might not or slightly be affected by evaporative fractionation,biodegradation and thermal maturity.1,2,4,5-/1,2,3,4-Te MB ratio and 1,2,4,5-Te MB content can be used as supplementary parameter for the identification of sedimentary environment and organic matter input.It should be noted that compared to the identification of organic matter sources,the 1,2,4,5-/1,2,3,4-Te MB parameter is more effective in identifying sedimentary environments.

关键词： 1 2 4 5-Tetramethylbenzene GC×GC-TOFMS Organic matter origin Depositional environment

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Rhodium-Catalyzed Asymmetric Transfer Hydrogenation of Heterocyclic Diaryl Ketones:Facile Access to Key Intermediate of Baloxavir

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Chinese Journal of Chemistry 2024年第1期42卷 43-47页

作者： Li Wang Renwei Xiao Jingyuan song Long-sheng Zheng Qiwei Lang Gen-Qiang Chen Xumu Zhang Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis Department of Chemistryand Medi-PingshanSouthern University of Science and TechnologyShenzhenGuangdong 518000China Academy for Advanced Interdisciplinary Studies Southern Universityof Science and TechnologyShenzhenGuangdong 518000China Chemistry and Chemical Engineering Guangdong Laboratory ShantouGuangdong 515031China

Transition metal-catalyzed asymmetric transfer hydrogenation has been proven to be a powerful approach for the synthesis of chiral alcohols.Herein,a highly efficient and enantioselective transfer hydrogenation of dibenzoheptaheterocyclic ketones catalyzed by an arene-tethered TsDPEN-based Rh(ll)catalyst has been successfully developed,and a variety of dibenzoheptaheterocyclic ketones were reduced by a 1/1 mixture of formic acid and DBU(1,8-diazabicyclo[5.4.0]undec-7-ene)with high yields and enantioselectivities.With this method,the asymmetric reduction of 7,8-difluorodibenzo[b,e]thiepin-11(6H)-one has been realized,providing the key intermediate of baloxavir marboxil with>99% yield and>99% ee at a substrate/catalyst molar ratio of 1000.

关键词： Asymmetric transfer hydrogenation Baloxavir Chiral alcohol Enantioselectivity Heterocyclic diaryl ketone Rhodium(Ⅱ)

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Clinical pathological characteristics of“crawling-type”gastric adenocarcinoma cancer:A case report

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1660-1667页

作者： Yong-Wei Xu Yan song Jun Tian Ba-Cui Zhang Yu-sheng Yang Jing Wang Department of Gastroenterology Songjiang HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 201600China Department of Pathology Songjiang HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 201600China

BACKGROUND Gastric cancer(GC)is a significant health problem worldwide,and early detection and accurate diagnosis are crucial for improving patient outcomes.Crawling-type gastric adenocarcinoma is a rare subtype of GC that has unique histopathological and clinical characteristics,and its diagnosis and management can be challenging.This pathological type of GC is also rare.CASE SUMMARY Here,we report the case of a patient who underwent ordinary endoscopy,na-rrow-band imaging,and endoscopic ultrasonography intending to determine the extent of tumor invasion and upper abdominal enhanced computed tomography and whether there was tumor metastasis.Then,endoscopic submucosal dissection was performed.After pathological and immunohistochemical examination,the pathological diagnosis was crawling-type gastric adenocarcinoma.This is a very rare and special pathological type of tumor.This case highlights the importance of using advanced endoscopic techniques and pathological examination in diagnosing and managing gastric crawling-type adenocarcinoma.Moreover,the findings underscore the need for continued research and clinical experience in this rare subtype of GC to improve patient outcomes.CONCLUSION The“crawling-type”GC is a rare and specific tumor pathology.It is difficult to identify and diagnose gliomas via endoscopy.The tumor is ill-defined,with a flat appearance and indistinct borders due to the lack of contrast against the background mucosa.Pathology revealed that the tumor cells were hand-like,so the patient has diagnosed with“crawling-type”gastric adenocarcinoma.

关键词： Clinicopathological Crawling-type gastric Pathology Gastric cancer Gastric adenocarcinoma cancer Case report

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Advances of nanoparticles in transmucosal drug delivery

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Nano Research 2024年第4期17卷 2874-2885页

作者： Li Zhang Changwei Yang Yingxiang song Tao sheng Junyan Li Jicheng Yu Xiaohong Wu Xiao Ye Geriatric Medicine Center Department of EndocrinologyZhejiang Provincial People’s Hospital(Affiliated People’s HospitalHangzhou Medical College)Hangzhou 310014China Key Laboratory of Advanced Drug Delivery Systems of Zhejiang Province College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China Jinhua Institute of Zhejiang University Jinhua 321299China Liangzhu Laboratory Zhejiang University Medical CenterHangzhou 311121China Department of General Surgery Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou 310016China National Key Laboratory of Advanced Drug Delivery and Release Systems Zhejiang UniversityHangzhou 310058China Key Laboratory for Diagnosis and Treatment of Endocrine Gland Diseases of Zhejiang Province Hangzhou 310014China

Transmucosal drug administration represents a potential strategy for enhancing treatment efficacy and reducing side effects by avoiding the first-pass effect into the systemic circulation and delivering therapeutics directly to the target disease site.However,many challenges still remain in its clinical application,including low drug availability and limited retention time in the mucosa.The burgeoning advancement of nanotechnologies offers great potential to overcome the above limitations,leveraging their distinct advantages of high drug-loading capacity and strong permeability.In this review,the latest developments of nanoparticles(NPs)in transmucosal drug delivery as well as their clinical applications are discussed.

关键词： nanoparticles(NPs) transmucosal drug delivery mucosal barriers biomaterials

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Monotropein Induced Apoptosis and Suppressed Cell Cycle Progression in Colorectal Cancer Cells

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Chinese Journal of Integrative Medicine 2024年第1期30卷 25-33页

作者： GAO Quan LI Lin ZHANG Qi-man sheng Qin-song ZHANG Ji-liang JIN Li-jun SHANG Rui-yan School of Pharmacy and Department of Medical Oncology the Affiliated Hospital of Hangzhou Normal UniversityHangzhou Normal UniversityHangzhou(311121)China Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines Engineering Laboratory of Development and Application of Traditional Chinese MedicinesCollaborative Innovation Center of Traditional Chinese Medicines of Zhejiang ProvinceHangzhou Normal UniversityHangzhou(311121)China Department of Colorectal Surgery the First Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhouChina Beijing Tong Ren Tang Chinese Medicine Co. Ltd.Beijing(100000)China Department of Traditional Chinese Medicine Hangzhou Shangcheng District People's HospitalHangzhou(310006)China Department of Gynecology Hangzhou Women's HospitalHangzhou(310008)China

Objective: To determine whether monotropein has an anticancer effect and explore its potential mechanisms against colorectal cancer(CRC) through network pharmacology and molecular docking combined with experimental verification. Methods: Network pharmacology and molecular docking were used to predict potential targets of monotropein against CRC. Cell counting kit assay, plate monoclonal assay and microscopic observation were used to investigate the antiproliferative effects of monotropein on CRC cells HCT116, HT29 and LoVo. Flow cytometry and scratch assay were used to analyze apoptosis and cell cycle, as well as cell migration, respectively in HCT116, HT29, and LoVo cells. Western blotting was used to detect the expression of proteins related to apoptosis, cell cycle, and cell migration, and the expression of proteins key to the Akt pathway. Results: The Gene Ontology and Reactome enrichment analyses indicated that the anticancer potential of monotropein against CRC might be involved in multiple cancer-related signaling pathways. Among these pathways, RAC-beta serine/threonine-protein kinase(Akt1, Akt2), cyclin-dependent kinase 6(CDK6), matrix metalloproteinase-9(MMP9), epidermal growth factor receptor(EGFR), cell division control protein 42 homolog(CDC42) were shown as the potential anticancer targets of monotropein against CRC. Molecular docking suggested that monotropein may interact with the 6 targets(Akt1, Akt2, CDK6, MMP9, EGFR, CDC42). Subsequently, cell activity of HCT116, HT29 and LoVo cell lines were significantly suppressed by monotropein(P<0.05). Furthermore, our research revealed that monotropein induced cell apoptosis by inhibiting Bcl-2 and increasing Bax, induced G_1–S cycle arrest in colorectal cancer by decreasing the expressions of CyclinD1, CDK4 and CDK6, inhibited cell migration by suppressing the expressions of CDC42 and MMP9(P<0.05), and might play an anticancer role through Akt signaling pathway. Conclusions: Monotropein exerts its antitumor effects primarily by arresting the cell cycle,

关键词： monotropein Chinese medicine anticancer activity colorectal cancer cells network pharmacology

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Prognostic significance of grade of malignancy based on histopathological differentiation and Ki-67 in pancreatic ductal adenocarcinoma

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Cancer Biology & Medicine 2024年第5期21卷 416-432页

作者： Yuexiang Liang Guannan sheng Yu Guo Yiping Zou Hanhan Guo Zhifei Li Shaofei Chang Quan Man song Gao Jihui Hao Department of Pancreatic Cancer Tianjin Medical University Cancer Institute & Hospital National Clinical Research Center for Cancer Key Laboratory of Cancer Prevention and TherapyTianjin Tianjin's Clinical Research Center for Cancer Department of Gastrointestinal Oncology The First Affiliated Hospital of Hainan Medical University Department of Gastrointestinal Pancreatic Surgery Shanxi Provincial People's Hospital

Objective: Tumor cell malignancy is indicated by histopathological differentiation and cell proliferation. Ki-67, an indicator of cellular proliferation, has been used for tumor grading and classification in breast cancer and neuroendocrine tumors. However, its prognostic significance in pancreatic ductal adenocarcinoma(PDAC) remains uncertain.Methods: Patients who underwent radical pancreatectomy for PDAC were retrospectively enrolled, and relevant prognostic factors were examined. Grade of malignancy(GOM), a novel index based on histopathological differentiation and Ki-67, is proposed, and its clinical significance was evaluated.Results: The optimal threshold for Ki-67 was determined to be 30%. Patients with a Ki-67 expression level > 30% rather than ≤ 30% had significantly shorter 5-year overall survival(OS) and recurrence-free survival(RFS). In multivariate analysis, both histopathological differentiation and Ki-67 were identified as independent prognostic factors for OS and RFS. The GOM was used to independently stratify OS and RFS into 3 tiers, regardless of TNM stage and other established prognostic factors. The tumor-nodemetastasis-GOM stage was used to stratify survival into 5 distinct tiers, and surpassed the predictive performance of TNM stage for OS and RFS.Conclusions: Ki-67 is a valuable prognostic indicator for PDAC. Inclusion of the GOM in the TNM staging system may potentially enhance prognostic accuracy for PDAC.

关键词： Ki-67 Pancreatic ductal adenocarcinoma TNM stage differentiation prognosis

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Interpretation and characterization of rate of penetration intelligent prediction model

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Petroleum Science 2024年第1期21卷 582-596页

作者： Zhi-Jun Pei Xian-Zhi song Hai-Tao Wang Yi-Qi Shi Shou-Ceng Tian Gen-sheng Li College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Petroleum Resources and Prospecting Beijing102249China Kunlun Digital Technology Co. Ltd.Beijing102206China

Accurate prediction of the rate of penetration(ROP)is significant for drilling optimization.While the intelligent ROP prediction model based on fully connected neural networks(FNN)outperforms traditional ROP equations and machine learning algorithms,its lack of interpretability undermines its credibility.This study proposes a novel interpretation and characterization method for the FNN ROP prediction model using the Rectified Linear Unit(ReLU)activation function.By leveraging the derivative of the ReLU function,the FNN function calculation process is transformed into vector operations.The FNN model is linearly characterized through further simplification,enabling its interpretation and analysis.The proposed method is applied in ROP prediction scenarios using drilling data from three vertical wells in the Tarim Oilfield.The results demonstrate that the FNN ROP prediction model with ReLU as the activation function performs exceptionally well.The relative activation frequency curve of hidden layer neurons aids in analyzing the overfitting of the FNN ROP model and determining drilling data similarity.In the well sections with similar drilling data,averaging the weight parameters enables linear characterization of the FNN ROP prediction model,leading to the establishment of a corresponding linear representation equation.Furthermore,the quantitative analysis of each feature's influence on ROP facilitates the proposal of drilling parameter optimization schemes for the current well section.The established linear characterization equation exhibits high precision,strong stability,and adaptability through the application and validation across multiple well sections.

关键词： Fully connected neural network Explainable artificial intelligence Rate of penetration ReLU active function Deep learning Machine learning

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