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1.
BMC Plant Biol ; 24(1): 106, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38342898

RESUMO

BACKGROUND: The genus Libanotis Haller ex Zinn, nom. cons., a contentious member of Apiaceae, encompasses numerous economically and medicinally significant plants, comprising approximately 30 species distributed across Eurasia. Despite many previous taxonomic insights into it, phylogenetic studies of the genus are still lacking. And the establishment of a robust phylogenetic framework remains elusive, impeding advancements and revisions in the taxonomic system for this genus. Plastomes with greater variability in their genetic characteristics hold promise for building a more robust Libanotis phylogeny. RESULTS: During our research, we sequenced, assembled, and annotated complete plastomes for twelve Libanotis species belong to three sections and two closely related taxa. We conducted a comprehensive comparative analysis through totally thirteen Libanotis plastomes for the genus, including an additional plastome that had been published. Our results suggested that Libanotis plastome was highly conserved between different subclades, while the coding regions were more conserved than the non-coding regions, and the IR regions were more conserved than the single copy regions. Nevertheless, eight mutation hotspot regions were identified among plastomes, which can be considered as candidate DNA barcodes for accurate species identification in Libanotis. The phylogenetic analyses generated a robustly framework for Libanotis and revealed that Libanotis was not a monophyletic group and their all three sections were polygenetic. Libanotis schrenkiana was sister to L. sibirica, type species of this genus, but the remainders scattered within Selineae. CONCLUSION: The plastomes of Libanotis exhibited a high degree of conservation and was effective in enhancing the support and resolution of phylogenetic analyses within this genus. Based on evidence from both phylogeny and morphology, we propose the recognition of "Libanotis sensu stricto" and provide taxonomic recommendations for other taxa that previously belonged to Libanotis. In conclusion, our study not only revealed the phylogenetic position and plastid evolution of Libanotis, but also provided new insights into the phylogeny of the family Apiaceae and phylogenetic relationships within the tribe Selineae.


Assuntos
Apiaceae , Filogenia , Evolução Molecular , Plastídeos/genética , Plantas
2.
BMC Plant Biol ; 24(1): 70, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38263006

RESUMO

BACKGROUND: The genus Sanicula L. is a unique perennial herb that holds important medicinal values. Although the previous studies on Sanicula provided us with a good research basis, its taxonomic system and interspecific relationships have not been satisfactorily resolved, especially for those endemic to China. Moreover, the evolutionary history of this genus also remains inadequately understood. The plastid genomes possessing highly conserved structure and limited evolutionary rate have proved to be an effective tool for studying plant phylogeny and evolution. RESULTS: In the current study, we newly sequenced and assembled fifteen Sanicula complete plastomes. Combined with two previously reported plastomes, we performed comprehensively plastid phylogenomics analyses to gain novel insights into the evolutionary history of this genus. The comparative results indicated that the seventeen plastomes exhibited a high degree of conservation and similarity in terms of their structure, size, GC content, gene order, IR borders, codon bias patterns and SSRs profiles. Such as all of them displayed a typical quadripartite structure, including a large single copy region (LSC: 85,074-86,197 bp), a small single copy region (SSC: 17,047-17,132 bp) separated by a pair of inverted repeat regions (IRs: 26,176-26,334 bp). And the seventeen plastomes had similar IR boundaries and the adjacent genes were identical. The rps19 gene was located at the junction of the LSC/IRa, the IRa/SSC junction region was located between the trnN gene and ndhF gene, the ycf1 gene appeared in the SSC/IRb junction and the IRb/LSC boundary was located between rpl12 gene and trnH gene. Twelve specific mutation hotspots (atpF, cemA, accD, rpl22, rbcL, matK, ycf1, trnH-psbA, ycf4-cemA, rbcL-accD, trnE-trnT and trnG-trnR) were identified that can serve as potential DNA barcodes for species identification within the genus Sanicula. Furthermore, the plastomes data and Internal Transcribed Spacer (ITS) sequences were performed to reconstruct the phylogeny of Sanicula. Although the tree topologies of them were incongruent, both provided strong evidence supporting the monophyly of Saniculoideae and Apioideae. In addition, the sister groups between Saniculoideae and Apioideae were strongly suggested. The Sanicula species involved in this study were clustered into a clade, and the Eryngium species were also clustered together. However, it was clearly observed that the sections of Sanicula involved in the current study were not respectively recovered as monophyletic group. Molecular dating analysis explored that the origin of this genus was occurred during the late Eocene period, approximately 37.84 Ma (95% HPD: 20.33-52.21 Ma) years ago and the diversification of the genus was occurred in early Miocene 18.38 Ma (95% HPD: 10.68-25.28 Ma). CONCLUSION: The plastome-based tree and ITS-based tree generated incongruences, which may be attributed to the event of hybridization/introgression, incomplete lineage sorting (ILS) and chloroplast capture. Our study highlighted the power of plastome data to significantly improve the phylogenetic supports and resolutions, and to efficiently explore the evolutionary history of this genus. Molecular dating analysis explored that the diversification of the genus occurred in the early Miocene, which was largely influenced by the prevalence of the East Asian monsoon and the uplift of the Hengduan Mountains (HDM). In summary, our study provides novel insights into the plastome evolution, phylogenetic relationships, taxonomic framework and evolution of genus Sanicula.


Assuntos
Apiaceae , Sanicula , Filogenia , Plastídeos , Cloroplastos
3.
Gastric Cancer ; 27(2): 324-342, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310631

RESUMO

Helicobacter pylori (H. pylori, Hp) has been designated a class I carcinogen and is closely associated with severe gastric diseases. During colonization in the gastric mucosa, H. pylori develops immune escape by inducing host immune tolerance. The gastric epithelium acts as the first line of defense against H. pylori, with Toll-like receptors (TLRs) in gastric epithelial cells being sensitive to H. pylori components and subsequently activating the innate immune system. However, the mechanism of immune tolerance induced by H. pylori through the TLR signalling pathway has not been fully elucidated. In this research, we detected the expression of TLRs and inflammatory cytokines in GES-1 cells upon sustained exposure to H. pylori or H. pylori lysate from 1 to 30 generations and in Mongolian gerbils infected with H. pylori for 5 to 90 weeks. We found that the levels of TLR6 and inflammatory cytokines first increased and then dropped during the course of H. pylori treatment in vitro and in vivo. The restoration of TLR6 potentiated the expression of IL-1ß and IL-8 in GES-1 cells, which recruited neutrophils and reduced the colonization of H. pylori in the gastric mucosa of gerbils. Mechanistically, we found that persistent infection with H. pylori reduces the sensitivity of TLR6 to bacterial components and regulates the expression of inflammatory cytokines in GES-1 cells through TLR6/JNK signaling. The TLR6 agonist obviously alleviated inflammation in vitro and in vivo. Promising results suggest that TLR6 may be a potential candidate immunotherapy drug for H. pylori infection.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Animais , Humanos , Receptor 6 Toll-Like/metabolismo , Gerbillinae , Neoplasias Gástricas/metabolismo , Citocinas/metabolismo , Infecções por Helicobacter/complicações , Mucosa Gástrica/metabolismo
4.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1485-1493, 2024 Mar.
Artigo em Zh | MEDLINE | ID: mdl-38621932

RESUMO

Chuanxiong Rhizoma is a well-known Sichuan-specific herbal medicine. Its original plant, Ligusticum chuanxiong, has been cultivated asexually for a long time. L. chuanxiong has sexual reproductive disorders, which restricts its germplasm innovation. However, there is little research on the reproductive system of L. chuanxiong. This study is based on a comparative anatomical research approach, using morphological dissection, paraffin sectioning, staining and compression, and combined with scanning electron microscopy technology, to observe and compare the flowers, fruits, and seeds at various stages of reproductive growth of L. chuanxiong and its wild relative L. sinense. The results showed that the meiosis of pollen mother cells is abnormal in L. chuanxiong anthers, and the size and number of microspores are uneven and inconsistent in the tetrad stage. tapetum cells are not completely degenerated during anther development. During the pollen ripening stage, there are fine cracks in the anther wall, while most anthers could not release pollen normally. The surface of mature pollen grains is concave and partially deformed, and the pollens are all inactive and cannot germinate in vitro. The starch, polysaccharides, and lipids in the pollen were insufficient. The filaments of L. chuanxiong are short at the flowering stage and recurved downward. Double-hanging fruits were observed in the fruiting stage, being wrinkled; with shriveled seeds. Compared with L. sinense at the same stage, the anthers of L. sinense developed normally, and the pollen grains are vigorous and can germinate in vitro. The double-hanging fruits of L. sinense are full and normal; at the flowering period, the filaments are long and erect, significantly higher than the stigma. Mature blastocysts are visible in the ovary of both L. chuanxiong and L. sinense, and there is no significant difference in stigmas. The conclusion is that during the development of L. chuanxiong stamens, the meiosis of pollen mother cells is abnormal, and tetrad, tapetum, filament and other pollen structures develop abnormally. L. chuanxiong has the characteristic of male infertility, which is an important reason for its sexual reproductive disorders.


Assuntos
Ligusticum , Reprodução , Pólen , Flores , Polissacarídeos
5.
BMC Plant Biol ; 23(1): 70, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36726056

RESUMO

The subgenus Rhizirideum in the genus Allium consists of 38 species worldwide and forms five sections (A. sect. Rhizomatosa, A. sect. Tenuissima, A. sect. Rhizirideum, A. sect. Eduardia, and A. sect. Caespitosoprason), A. sect. Caespitosoprason being merged into A. sect. Rhizomatosa recently. Previous studies on this subgenus mainly focused on separate sections. To investigate the inter-section and inter-subgenera phylogenetic relationships and adaptive evolution of A. subg. Rhizirideum, we selected thirteen representative species, which cover five sections of this subgenus and can represent four typical phenotypes of it. We conducted the comparative plastome analysis with our thirteen plastomes. And phylogenetic inferences with CDSs and complete sequences of plastomes of our thirteen species and another fifty-four related species were also performed. As a result, the A. subg. Rhizirideum plastomes were relatively conservative in structure, IR/SC borders, codon usage, and repeat sequence. In phylogenetic results, the inter-subgenera relationships among A. subg. Rhizirideum and other genus Allium subgenera were generally similar to the previous reports. In contrast, the inter-section relationships within our subgenus A. subg. Rhizirideum were newly resolved in this study. A. sect. Rhizomatosa and A. sect. Tenuissima were sister branches, which were then clustered with A. sect. Rhizirideum and A. sect. Eduardia successively. However, Allium Polyrhizum Turcz. ex Regel, type species of A. sect. Caespitosoprason, was resolved as the basal taxon of A. subg. Rhizirideum. Allium siphonanthum J. M. Xu was also found in clade A. subg. Cyathophora instead of clade A. subg. Rhizirideum. The selective pressure analysis was also conducted, and most protein-coding genes were under purifying selection. At the same time, just one gene, ycf2, was found under positive selection, and another three genes (rbcL, ycf1a, ycf1b) presented relaxed selection, which were all involved in the photosynthesis. The low temperature, dry climate, and high altitude of the extreme habitats where A. subg. Rhizirideum species grow might impose intense natural selection forces on their plastome genes for photosynthesis. In summary, our research provides new insights into the phylogeny and adaptive evolution of A. subg. Rhizirideum. Moreover, we suggest that the positions of the A. subg. Rhizirideum species A. polyrhizum and A. siphonanthum should be reconsidered.


Assuntos
Allium , Amaryllidaceae , Genomas de Plastídeos , Allium/genética , Amaryllidaceae/genética , Filogenia , Sequências Repetitivas de Ácido Nucleico , Evolução Molecular
6.
BMC Plant Biol ; 23(1): 9, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36604614

RESUMO

BACKGROUND: The Ferula genus encompasses 180-185 species and is one of the largest genera in Apiaceae, with many of Ferula species possessing important medical value. The previous studies provided more information for Ferula, but its infrageneric relationships are still confusing. In addition, its genetic basis of its adaptive evolution remains poorly understood. Plastid genomes with more variable sites have the potential to reconstruct robust phylogeny in plants and investigate the adaptive evolution of plants. Although chloroplast genomes have been reported within the Ferula genus, few studies have been conducted using chloroplast genomes, especially for endemic species in China. RESULTS: Comprehensively comparative analyses of 22 newly sequenced and assembled plastomes indicated that these plastomes had highly conserved genome structure, gene number, codon usage, and repeats type and distribution, but varied in plastomes size, GC content, and the SC/IR boundaries. Thirteen mutation hotspot regions were detected and they would serve as the promising DNA barcodes candidates for species identification in Ferula and related genera. Phylogenomic analyses with high supports and resolutions showed that Talassia transiliensis and Soranthus meyeri were nested in the Ferula genus, and thus they should be transferred into the Ferula genus. Our phylogenies also indicated the monophyly of subgenera Sinoferula and subgenera Narthex in Ferula genus. Twelve genes with significant posterior probabilities for codon sites were identified in the positively selective analysis, and their function may relate to the photosystem II, ATP subunit, and NADH dehydrogenase. Most of them might play an important role to help Ferula species adapt to high-temperatures, strong-light, and drought habitats. CONCLUSION: Plastome data is powerful and efficient to improve the support and resolution of the complicated Ferula phylogeny. Twelve genes with significant posterior probabilities for codon sites were helpful for Ferula to adapt to the harsh environment. Overall, our study supplies a new perspective for comprehending the phylogeny and evolution of Ferula.


Assuntos
Ferula , Genoma de Cloroplastos , Genomas de Plastídeos , Filogenia , Evolução Molecular , Genoma de Cloroplastos/genética , Códon/genética
7.
BMC Plant Biol ; 22(1): 101, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35255817

RESUMO

BACKGROUND: The Peucedanum genus is the backbone member of Apiaceae, with many economically and medically important plants. Although the previous studies on Peucedanum provide us with a good research basis, there are still unclear phylogenetic relationships and many taxonomic problems in Peucedanum, and a robust phylogenetic framework of this genus still has not been obtained, which severely hampers the improvement and revision of taxonomic system for this genus. The plastid genomes possessing more variable characters have potential for reconstructing a robust phylogeny in plants. RESULTS: In the current study, we newly sequenced and assembled seven Peucedanum plastid genomes. Together with five previously published plastid genomes of Peucedanum, we performed a comprehensively comparative analyses for this genus. Twelve Peucedanum plastomes were similar in terms of genome structure, codon bias, RNA editing sites, and SSRs, but varied in genome size, gene content and arrangement, and border of SC/IR. Fifteen mutation hotspot regions were identified among plastid genomes that can serve as candidate DNA barcodes for species identification in Peucedanum. Our phylogenetic analyses based on plastid genomes generated a phylogeny with high supports and resolutions for Peucedanum that robustly supported the non-monophyly of genus Peucedanum. CONCLUSION: The plastid genomes of Peucedanum showed both conservation and diversity. The plastid genome data were efficient and powerful for improving the supports and resolutions of phylogeny for the complex Peucedanum genus. In summary, our study provides new sights into the plastid genome evolution, taxonomy, and phylogeny for Peucedanum species.


Assuntos
Apiaceae/classificação , Apiaceae/genética , Classificação , Evolução Molecular , Genomas de Plastídeos , Filogenia , China , Variação Genética , Tamanho do Genoma , Genótipo
8.
BMC Plant Biol ; 22(1): 534, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36380268

RESUMO

BACKGROUND: The genus Seseli L., which consists of 125-140 species distributed in the Old World from western Europe and northwestern Africa to China and Japan, is one of the largest and most taxonomically difficult genera of Apiaceae Lindl. Although several previous studies have been conducted on Seseli based on limited morphological characteristics and molecular fragments, a robust and comprehensive phylogeny of Seseli remains elusive. Plastomes provide abundant genetic information and have been widely used in studying plant phylogeny and evolution. Consequently, we newly generated the complete plastomes of eleven Seseli taxa. We combined plastome data and morphological characteristics to investigate the phylogeny of Seseli. RESULTS: In our study, we observed that the genome length, gene numbers, IR/SC borders, and repeat composition of the eleven Seseli plastomes were variable. Several appropriate mutation hotspot regions may be developed as candidate DNA barcodes for evolution, phylogeny, and species identification of Seseli. The phylogenetic results identified that Seseli was not a monophyletic group. Moreover, the eleven newly sequenced Seseli taxa did not cluster with S. tortuosum (the type species of Seseli, belonging to the tribe Selineae), where S. delavayi clustered with Eriocycla belonging to the tribe Echinophoreae and the other ten belonged to Selineae. The comparative plastome and morphological characteristics analyses confirmed the reliability of the phylogenetic analyses and implied the complex evolution of Seseli. CONCLUSION: Combining molecular and morphological data is efficient and useful for studying the phylogeny of Seseli. We suggest that "a narrow sense" of Seseli will be meaningful for further study and the current taxonomic system of Seseli needs to be revised. In summary, our study can provide new insights into the phylogenetic relationships and taxonomic framework of Seseli.


Assuntos
Apiaceae , Filogenia , Apiaceae/genética , Evolução Molecular , Reprodutibilidade dos Testes , Sequência de Bases
9.
Planta ; 256(6): 117, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376499

RESUMO

MAIN CONCLUSION: Members of Apiales are monophyletic and radiated in the Late Cretaceous. Fruit morphologies are critical for Apiales evolution and negative selection and mutation pressure play important roles in environmental adaptation. Apiales include many foods, spices, medicinal, and ornamental plants, but the phylogenetic relationships, origin and divergence, and adaptive evolution remain poorly understood. Here, we reconstructed Apiales phylogeny based on 72 plastid genes from 280 species plastid genomes representing six of seven families of this order. Highly supported phylogenetic relationships were detected, which revealed that each family of Apiales is monophyletic and confirmed that Pennanticeae is a member of Apiales. Genera Centella and Dickinsia are members of Apiaceae, and the genus Hydrocotyle previously classified into Apiaceae is confirmed to belong to Araliaceae. Besides, coalescent phylogenetic analysis and gene trees cluster revealed ten genes that can be used for distinguishing species among families of Apiales. Molecular dating suggested that the Apiales originated during the mid-Cretaceous (109.51 Ma), with the families' radiation occurring in the Late Cretaceous. Apiaceae species exhibit higher differentiation compared to other families. Ancestral trait reconstruction suggested that fruit morphological evolution may be related to shifts in plant types (herbaceous or woody), which in turn is related to the distribution areas and species numbers. Codon bias and positive selection analyses suggest that negative selection and mutation pressure may play important roles in environmental adaptation of Apiales members. Our results improve the phylogenetic framework of Apiales and provide insights into the origin, divergence, and adaptive evolution of this order and its members.


Assuntos
Genomas de Plastídeos , Magnoliopsida , Filogenia , Evolução Molecular , Genomas de Plastídeos/genética , Plastídeos/genética , Magnoliopsida/genética
10.
BMC Pediatr ; 22(1): 286, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35581572

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is diagnosed increasingly in children and adolescents. We aimed to investigate the prevalence and related influencing factors of NAFLD in school-aged children and adolescents in Shenyang, Liaoning Province. Furthermore, we analyzed the relationship between lifestyle and fatty liver. METHODS: We conducted aprospective cohort study of 1309 school-aged children and adolescents between the ages of 7 and 18 years who underwent physical examination from November to December 2019. In addition, they were collected age, gender, learning stage, height, weight, BMI, waist circumference, hip circumference, and waist-hip ratio. Finally, a portion of the population was selected to complete a questionnaire survey to explore the impact of lifestyle habits on fatty liver disease. RESULTS: NAFLD was present in 23.83% of subjects. The prevalence of children and adolescents was 22.73% and 24.43%, respectively. Fatty liver prevalence differs significantly by gender and learning stages. The highest rate of fatty liver was seen in obese children (71.68%). Moreover, exercise, diet, and parental factors can affect children with fatty liver. CONCLUSIONS: NAFLD is very prevalent in children and adolescents in Shenyang city. Due to the close relationship between NAFLD and obesity, lifestyle plays a major role in the occurrence of NAFLD. TRIAL REGISTRATION: The First Affiliated Hospital of China Medical University, [2020] 2020-258-2. Registered 6 June 2020-Retrospectively registered.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Obesidade Infantil , Adolescente , Índice de Massa Corporal , Criança , Estudos de Coortes , Humanos , Estilo de Vida , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Obesidade Infantil/epidemiologia , Prevalência , Fatores de Risco , Inquéritos e Questionários
11.
BMC Musculoskelet Disord ; 23(1): 641, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35791024

RESUMO

PURPOSE: To investigate the relationship between the preoperative paraspinal Goutalier grade of fatty infiltration and postoperative cervical sagittal alignment in patients undergoing anterior cervical discectomy and fusion (ACDF). METHODS: A total of 101 patients who underwent single-level ACDF with the Zero-profile implant system between March 2011 and April 2020 were included in this study. Cervical sagittal alignment parameters, including the C2-C7 Cobb angle, functional spinal unit (FSU) angle, cervical sagittal vertical axis (SVA), and T1 slope (T1S), were assessed. Preoperative magnetic resonance images were used to classify patients according to Goutalier grade. Clinical outcomes including Neck Disability Index (NDI) scores, Japanese Orthepaedic Association (JOA) scores and Visual Analogue Scale (VAS) scores were collected and analyzed. RESULTS: According to the Goutalier grade, 33 patients were classified as Goutalier 0-1 (Group A), 44 were classified as Goutalier 1.5-2 (Group B), and 24 were classified as Goutalier 2.5-4.0 (Group C). The mean age among the three groups showed significant differences (P = 0.007). At the last follow-up, the C2-C7 Cobb angle, FSU angle, and T1S improved after the surgery among the groups. Although there were varying degrees of loss of curvature among the different groups during the follow-up period, the postoperative cervical sagittal alignment parameters demonstrated no statistical differences among the three groups (P > 0.05). In addition, patients in all groups experienced significant relief of their symptoms, and the clinical scores were comparable among the groups (P > 0.05). CONCLUSION: The complex nature of anterior cervical surgery requires surgical attention both in decompression and sagittal alignment. Our study demonstrates satisfactory postoperative cervical sagittal alignment of patients despite different grades of fatty infiltration of the multifidus muscle following single-level ACDF. Based on our results, the improvement and maintenance of cervical sagittal alignment after ACDF remains a complex problem that spine surgeons should consider before surgery.


Assuntos
Vértebras Cervicais , Fusão Vertebral , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Discotomia/métodos , Humanos , Músculos/cirurgia , Pescoço , Fusão Vertebral/efeitos adversos , Fusão Vertebral/métodos
12.
Sensors (Basel) ; 22(10)2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35632204

RESUMO

This paper presents a monitoring system based on Global Navigation Satellite System (GNSS) reflected signals to provide real-time observations of sea conditions. Instead of a computer, the system uses a custom-built hardware platform that incorporates Radio Frequency (RF), Field Programmable Gate Array (FPGA), Digital Signal Processing (DSP), and Raspberry Pi for real-time signal processing. The suggested structure completes the navigation signal's positioning as well as the reflected signal's feature extraction. Field tests are conducted to confirm the effectiveness of the system and the retrieval algorithm described in this research. The entire system collects and analyzes signals at a coastal site in the field experiment, producing sea surface wind speed and significant wave height (SWH) that are compared to local weather station data, demonstrating the system's practicality. The system can allow the centralized monitoring of many sites, as well as field experiments and real-time early warning at sea.

13.
Angew Chem Int Ed Engl ; 61(44): e202207824, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36082970

RESUMO

Oxidative N-heterocyclic carbene (NHC) organocatalysis, typically leading to the formation of acyl azolium reactive intermediates, constitutes one of the most important activation strategies for the NHC-catalyzed chemical transformations. Here, we report an unprecedented oxidative radical NHC catalysis by using peroxyester as the external single-electron oxidant to realize divergent difunctionalization of olefins. The key to success of this chemistry is the catalytic generation of oxygen radicals that could trigger an intermolecular hydrogen atom transfer to activate the inert C-H bonds, thereby enabling the productive radical relay process. With this protocol, commonly used general chemicals could serve as radical precursors to allow efficient synthesis of value-added products in a straightforward and cost-effective manner. Preliminary mechanistic investigations, including control experiments and DFT calculations, shed light on the NHC organocatalytic radical reaction mechanism.

14.
Mol Phylogenet Evol ; 161: 107183, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33892097

RESUMO

Traditional phylogenies inferred from chloroplast DNA fragments have not obtained a well-resolved evolutionary history for the backbone of Apioideae, the largest subfamily of Apiaceae. In this study, we applied the genome skimming approach of next-generation sequencing to address whether the lack of resolution at the tip of the Apioideae phylogenetic tree is due to limited information loci or the footprint of ancient radiation. A total of 90 complete chloroplast genomes (including 23 newly sequenced genomes and covering 20 major clades of Apioideae) were analyzed (RAxML and MrBayes) to provide a phylogenomic reconstruction of Apioideae. Dating analysis was also implemented using BEAST to estimate the origin and divergence time of the major clades. As a result, the early divergences of Apioideae have been clarified but the relationship among its distally branching clades (Group A) was only partially resolved, with short internal branches pointing to an ancient radiation scenario. Four major clades, Tordyliinae I, Pimpinelleae I, Apieae and Coriandreae, were hypothesized to have originated from chloroplast capture events induced by early hybridization according to the incongruence between chloroplast-based and nrDNA-based phylogenetic trees. Furthermore, the variable and nested distribution of junction positions of LSC (Large single copy region) and IRB (inverted repeat region B) in Group A may reflect incomplete lineage sorting within this group, which possibly contributed to the unclear phylogenetic relationships among these clades inferred from plastome data. Molecular clock analysis revealed the chloroplast capture events mainly occurred during the middle to late Miocene, providing a geological and climate context for the evolution of Apioideae.


Assuntos
Apiaceae/genética , Evolução Molecular , Genoma de Cloroplastos/genética , Filogenia , Plastídeos/genética , Análise de Sequência de DNA
15.
BMC Infect Dis ; 21(1): 813, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34388976

RESUMO

BACKGROUND: Part of tuberculosis (TB) patients were missed if symptomatic screening was based on the main TB likely symptoms. This study conducted to compare the yield and relative costs of different TB screening algorithms in active case-finding in the whole population in China. METHODS: The study population was screened based on the TB likely symptoms through a face-to-face interview in selected 27 communities from 10 counties of 10 provinces in China. If the individuals had any of the enhanced TB likely symptoms, both chest X-ray and sputum tests were carried out for them furtherly. We used the McNemar test to analyze the difference in TB detection among four algorithms in active case-finding. Of four algorithms, two were from WHO recommendations including 1a/1c, one from China National Tuberculosis Program, and one from this study with the enhanced TB likely symptoms. Furthermore, a two-way ANOVA analysis was performed to analyze the cost difference in the performance of active case-finding adjusted by different demographic and health characteristics among different algorithms. RESULTS: Algorithm with the enhanced TB likely symptoms defined in this study could increase the yield of TB detection in active case-finding, compared with algorithms recommended by WHO (p < 0.01, Kappa 95% CI: 0. 93-0.99) and China NTP (p = 0.03, Kappa 95% CI: 0.96-1.00). There was a significant difference in the total costs among different three algorithms WHO 1c/2/3 (F = 59.13, p < 0.01). No significant difference in the average costs for one active TB case screened and diagnosed through the process among Algorithms 1c/2/3 was evident (F = 2.78, p = 0.07). The average costs for one bacteriological positive case through algorithm WHO 1a was about two times as much as the costs for one active TB case through algorithms WHO 1c/2/3. CONCLUSIONS: Active case-finding based on the enhanced symptom screening is meaningful for TB case-finding and it could identify more active TB cases in time. The findings indicated that this enhanced screening approach cost more compared to algorithms recommend by WHO and China NTP, but the increased yield resulted in comparative costs per patient. And it cost much more that only smear/bacteriological-positive TB cases are screened in active case-finding.


Assuntos
Programas de Rastreamento/economia , Tuberculose/diagnóstico , Tuberculose/economia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Criança , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Escarro , Tuberculose/epidemiologia
16.
J Clin Lab Anal ; 35(6): e23816, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33982344

RESUMO

BACKGROUND: Serum biomarkers have been widely adopted in clinical practice for assisting lung cancer diagnoses, therapeutic monitoring, and prognostication. The function of a well-performing tumor biomarker depends on a reliable reference interval (RI) with consideration of the study subjects' age, gender, and geographical location. This study aimed to establish a RI for each of 6 lung cancer biomarkers for use in the whole country of China on Mindray platform. METHODS: The levels of serum 6 lung cancer biomarkers-namely progastrin-releasing peptide (ProGRP), neuron-specific enolase (NSE), squamous cell carcinoma antigen (SCC), carcinoembryonic antigen (CEA), cytokeratin-19 fragment (CYFRA21-1), and human epididymis protein 4 (HE4)-were measured utilizing the chemiluminescence immunoassay on the Mindray CL-6000i platform following the laboratory standard operating procedures in apparently healthy Chinese individuals on large cohort, multicenter, and geographical consideration bases. The CLSI EP28-A3C guideline was followed for the enrollment of study subjects. RESULTS: The age-stratified, gender-specific RIs for ProGRP, NSE, SCC, CEA, CYFRA21-1, and HE4 lung cancer biomarkers in the Chinese population have been established as described in the results and discussion in this work. In addition, various levels of the six lung cancer biomarkers among nine geographical locations in China have been observed. CONCLUSIONS: The sample volume of study cohort, age, and geographical location should be considered upon establishing a reliable biomarker RI. A RI for each of six lung cancer biomarkers has been established. The results from this study would be helpful for clinical laboratories in interpreting the analytical results and for clinicians in patient management.


Assuntos
Biomarcadores Tumorais/sangue , Imunoensaio/métodos , Neoplasias Pulmonares/diagnóstico , Adolescente , Adulto , Fatores Etários , Antígenos de Neoplasias/sangue , Antígeno Carcinoembrionário/sangue , Proteínas de Transporte/sangue , China , Estudos de Coortes , Feminino , Proteínas Ligadas por GPI/sangue , Geografia , Humanos , Queratina-19/sangue , Neoplasias Pulmonares/sangue , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/sangue , Prognóstico , Proteínas Recombinantes/sangue , Valores de Referência , Serpinas/sangue , Fatores Sexuais , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos/análise , Adulto Jovem
17.
Sensors (Basel) ; 21(2)2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33477471

RESUMO

Near real-time urban traffic analysis and prediction are paramount for effective intelligent transport systems. Whilst there is a plethora of research on advanced approaches to study traffic recently, only one-third of them has focused on urban arterials. A ready-to-use framework to support decision making in local traffic bureaus using largely available IoT sensors, especially CCTV, is yet to be developed. This study presents an end-to-end urban traffic volume detection and prediction framework using CCTV image series. The framework incorporates a novel Faster R-CNN to generate vehicle counts and quantify traffic conditions. Then it investigates the performance of a statistical-based model (SARIMAX), a machine learning (random forest; RF) and a deep learning (LSTM) model to predict traffic volume 30 min in the future. Tests at six locations with varying traffic conditions under different lengths of past time series are used to train the prediction models. RF and LSTM provided the most accurate predictions, with RF being faster than LSTM. The developed framework has been successfully applied to fill data gaps under adverse weather conditions when data are missing. It can be potentially implemented in near real time at any CCTV location and integrated into an online visualization platform.

18.
J Cell Physiol ; 235(10): 6563-6573, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32017068

RESUMO

As a polyphenolic compound, resveratrol (Res) is widely present in a variety of plants. Previous studies have shown that Res can inhibit various tumors. However, its role in c remains largely unexplored. In the present study, we first demonstrated that Res inhibited cell viability and induced apoptosis of glioblastoma A172 cell. Further experiments showed that Res induced mitochondrial dysfunction and activated the activity of caspase-9. Functional studies have found that Res treatment is associated with an increase in the expression of Pak2. Interestingly, inhibition of Pak2 could further augment the proapoptotic effect of Res. Mechanistically, Pak2 inhibition induced reactive oxygen species overproduction, mitochondria-JNK pathway activation, and AMPK-YAP axis suppression. However, overexpression of YAP could abolish the anticancer effects of Res and Pak2 inhibition, suggesting a necessary role played by the AMPK-YAP pathway in regulating cancer-suppressive actions of Res and Pak2 inhibition. Altogether, our results indicated that Res in combination with Pak2 inhibition could further enhance the anticancer property of Res and this effect is mediated via the AMPK-YAP pathway.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Resveratrol/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Quinases Ativadas por p21/antagonistas & inibidores , Caspase 9/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Sinalização YAP
19.
BMC Plant Biol ; 20(1): 519, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33187470

RESUMO

BACKGROUND: The genus Ligusticum consists of approximately 60 species distributed in the Northern Hemisphere. It is one of the most taxonomically difficult taxa within Apiaceae, largely due to the varied morphological characteristics. To investigate the plastome evolution and phylogenetic relationships of Ligusticum, we determined the complete plastome sequences of eight Ligusticum species using a de novo assembly approach. RESULTS: Through a comprehensive comparative analysis, we found that the eight plastomes were similar in terms of repeat sequence, SSR, codon usage, and RNA editing site. However, compared with the other seven species, L. delavayi exhibited striking differences in genome size, gene number, IR/SC borders, and sequence identity. Most of the genes remained under the purifying selection, whereas four genes showed relaxed selection, namely ccsA, rpoA, ycf1, and ycf2. Non-monophyly of Ligusticum species was inferred from the plastomes and internal transcribed spacer (ITS) sequences phylogenetic analyses. CONCLUSION: The plastome tree and ITS tree produced incongruent tree topologies, which may be attributed to the hybridization and incomplete lineage sorting. Our study highlighted the advantage of plastome with mass informative sites in resolving phylogenetic relationships. Moreover, combined with the previous studies, we considered that the current taxonomy system of Ligusticum needs to be improved and revised. In summary, our study provides new insights into the plastome evolution, phylogeny, and taxonomy of Ligusticum species.


Assuntos
Genomas de Plastídeos , Ligusticum/anatomia & histologia , Ligusticum/classificação , Ligusticum/genética , Filogenia , Análise de Sequência de DNA , Evolução Molecular , Genes de Plantas , Variação Genética , Genótipo
20.
Mol Phylogenet Evol ; 146: 106737, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31982455

RESUMO

Allium L. is one of the largest monocotyledonous genera with extensive distribution in the Northern Hemisphere. The fundamental phylogenies of Allium have been investigated using many morphological and molecular characters. However, the morphological characters may not agree with the molecular results in some Allium groups or sections (such as the Chinese Allium section Daghestanica), which may result in ambiguous species relationships and hinder further evolutionary and adaptive researches. Here, transcriptome sequences of the six Chinese endemics from Allium section Daghestanica were collected, with their single-copy genes (SCGs) were extracted. The interspecies relationships were analyzed using concatenation and coalescent methods. The branch-site model (BSM) was conducted to detect the positively selected genes (PSGs) in five highland species of this section. Based on 1644, 1281 and 1580 SCGs in flowers, leaves, and flowers-leaves combination respectively, a robust consistent and well-resolved phylogeny was generated from the concatenation method. Strong conflicts among individual gene trees were detected in the coalescent method, and morphological characters were incongruent with molecular relationships to some degree. Many PSGs were involved in responses of various stresses and stimuli (e.g. hypoxia, low temperature, aridity), DNA repair, metabolism, nutrient or energy intake, photosynthesis, and signal transduction. Our study revealed a clear interspecies relationship of Chinese endemics in Allium section Daghestanica and suggested that the discordance between morphological characters and molecular relationships might result from that the former are more susceptible to convergence compared with the latter. PSGs detected in our study may provide some insights into highland adaptation in Allium species.


Assuntos
Allium/classificação , Aclimatação , Allium/anatomia & histologia , Allium/genética , China , Flores/anatomia & histologia , Flores/genética , Perfilação da Expressão Gênica , Genes de Plantas , Filogenia , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética
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