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1.
BMC Med Educ ; 24(1): 651, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862950

RESUMO

OBJECTIVE: Currently, there are still some shortcomings in EBM education in China.The study aimed to investigate the effectiveness of the novel evidence-based medicine (EBM) learning model of "autonomy-collaboration." METHODS: A total of 91 undergraduate students majoring in clinical medicine at Zhongshan Clinical College of Dalian University from the 2019 batch were selected as the participants in this study. They were instructed to follow the EBM learning model of "autonomy-collaboration." Upon completion of the course, questionnaires, records of participants' sentiments and insights, and evidence-based clinical practice reports were used as indicators to evaluate the effectiveness of the training. RESULTS: This learning modality effectively enhanced independent learning ability of the students, stimulated their interest in learning, and strengthened the communication between students and teachers, thereby improving the quality of teaching. CONCLUSION: The novel EBM learning model of "autonomy-collaboration," exhibited robust effectiveness in instruction and facilitated the seamless integration of theoretical knowledge with clinical practice. Consequently, its widespread adoption is strongly recommended.


Assuntos
Educação de Graduação em Medicina , Medicina Baseada em Evidências , Estudantes de Medicina , Humanos , Medicina Baseada em Evidências/educação , Educação de Graduação em Medicina/métodos , China , Aprendizagem , Modelos Educacionais , Comportamento Cooperativo , Feminino , Masculino , Inquéritos e Questionários , Avaliação Educacional
2.
Chem Pharm Bull (Tokyo) ; 71(5): 349-353, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36858603

RESUMO

The direct modification of structurally complex natural product dehydroepiandrosterone (DHEA) through iron-catalyzed direct hydroamination of DHEA with various nitro(hetero)arenes was carried out to afford 5α-arylamino-DHEAs (1-25) in good yields (53-72%). Though as a radical reaction, it features high stereoselectivity, and only the 5α-substituted derivatives were produced. The in vitro antiproliferative activity of these synthesized compounds against the human breast cancer MCF-7 cell was evaluated, showing that most of DHEA analogues possessed the moderate cytotoxic activity. The preliminary structure-activity relationship analysis revealed that the electron-withdrawing groups installed at the para-position of arylamine ring had a great contribution to the improvement of the DHEA's cytotoxic potency. Among them, (4-trifluoromethylaniline)-DHEA (4) displayed the most potent cytotoxicity, with an IC50 value of 19.3 µM, which was 2.3-fold more active than DHEA.


Assuntos
Antineoplásicos , Desidroepiandrosterona , Humanos , Desidroepiandrosterona/farmacologia , Sulfato de Desidroepiandrosterona , Relação Estrutura-Atividade , Antineoplásicos/farmacologia , Catálise
3.
J Org Chem ; 88(7): 4765-4769, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-36989387

RESUMO

Using Eosin Y as a metal-free photocatalyst and O2 as an oxidant, the present study reports a new photochemical protocol that enables efficient aerobic oxidation of various benzyl alcohols to the corresponding aldehydes or ketones in excellent yields under mild reaction conditions. The catalyst system presents good functional-group tolerance and exquisite chemoselectivity, which also can easily be scaled-up to gram scale. Moreover, the methodological applications in practical synthesis of several organic molecules and the primary reaction mechanism were also discussed.

4.
Org Lett ; 25(4): 597-602, 2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36662155

RESUMO

The biorelevant sulfur-containing Euphorbia diterpenes with scarce 5/7/6/3 premyrsinane- and 5/7/6 myrsinane-type backbones were easily constructed from naturally abundant lathyrane-type Euphorbia factor L3 by visible-light-triggered tandem thiol-ene click reaction/transannular cyclization and regioselective cyclopropane ring-opening. The selenide diterpene was also successfully obtained to verify the system universality. This concise synthesis route gives an efficient strategy for obtaining structurally diverse Euphorbia diterpenes under very mild conditions and provides a promising anti-HIV bioactive premyrsinane diterpene 3h.


Assuntos
Diterpenos , Euphorbia , Ciclização , Estrutura Molecular
5.
Bioorg Chem ; 131: 106329, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36565674

RESUMO

A series of lathyrane-type Euphorbia diterpene derivatives featured 3R configuration (H-3ß) were synthesized from natural rich Euphorbia factor L3via modified Mitsunobu reaction based on configuration inversion strategy. The antiproliferation activity and MDR reversal ability of the lathyrane derivatives were evaluated, and the most synthesized compounds showed moderate or strong potencies. Among them, diterpenes 21 (IC50 values of 2.6, 5.2 and 13.1 µM, respectively) and 25 (IC50 values of 5.5, 8.6 and 1.3 µM, respectively) presented the strong cytotoxicity against MCF-7, 4 T1 and HepG2 cells. Meanwhile, derivative 25 exhibited excellent MDR reversal ability with the reversal fold of 16.1 higher than that of verapamil. The cellular thermal shift assay and molecular docking proved direct engagement of diterpene 25 to ABCB1, suggesting 25 could be a promising MDR modulator. Furthermore, the preliminary SARs of these diterpenes were also discussed.


Assuntos
Antineoplásicos , Diterpenos , Euphorbia , Humanos , Linhagem Celular Tumoral , Diterpenos/síntese química , Diterpenos/farmacologia , Euphorbia/química , Células Hep G2 , Simulação de Acoplamento Molecular , Estrutura Molecular , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia
6.
Org Lett ; 24(47): 8598-8602, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36403148

RESUMO

An efficient Ir-catalyzed biomimetic method for photoisomerization of cyclopropane in lathyrane-type Euphorbia diterpenes is reported. Lathyrane diterpenes featuring the trans-fused cyclopropane (1a-5a) were successfully prepared from cis-cyclopropane lathyranes (1-5) in excellent yields by this stereochemical permutations strategy, which first verified the biogenesis relationship between the lathyrane isomers. Moreover, 5a could further convert into another trans-isomer 5b. The present work provides a convenient route for easy access of naturally rare 12(Z)-trans-cyclopropane lathyranes.


Assuntos
Diterpenos , Euphorbia , Biomimética , Ciclopropanos , Catálise
7.
Front Aging Neurosci ; 14: 889257, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36072482

RESUMO

Objective: Matrix metalloproteinases (MMPs) are essential for tissue formation, neuronal network remodeling, and blood-brain barrier integrity. MMPs have been widely studied in acute brain diseases. However, the relationship with Parkinson's disease (PD) remains unclear. The purpose of this study was to evaluate the serum MMP3 and MMP9 levels of PD patients and analyze their correlation with non-motor symptoms. Methods: In this cross-sectional study, we recruited 73 patients with idiopathic PD and 64 healthy volunteers. Serum MMP3 and MMP9 levels were measured by enzyme-linked immunosorbent assay (ELISA). Patients with PD were assessed for non-motor symptoms using the Non-motor Symptoms Scale (NMSS) and Parkinson's disease sleep scale (PDSS) and Mini Mental State Examination (MMSE). Results: Serum MMP3 levels were significantly decreased in PD patients, predominantly those with early-stage PD, compared with controls [12.56 (9.30, 17.44) vs. 15.37 (11.33, 24.41) ng/ml; P = 0.004], and the serum MMP9 levels of PD patients were significantly higher than those of healthy controls [522 (419, 729) vs. 329 (229, 473) ng/ml; P < 0.001]. MMP3 levels were positively correlated with the NMSS total score (r = 0.271, P = 0.020) and the single-item scores for item six, assessing the gastrointestinal tract (r = 0.333, P = 0.004), and there was an inverse correlation between serum MMP3 levels and PDSS score (r = -0.246, P = 0.036); meanwhile, MMP9 levels were positively correlated with the NMSS total score (r = 0.234, P = 0.047), and higher serum MMP9 levels were detected in the cognitive dysfunction subgroup than in the cognitively intact subgroup [658 (504, 877) vs. 502 (397, 608) ng/ml, P = 0.008]. Conclusion: The serum MMP3 level of PD patients (especially early-stage patients) was significantly lower than that of the healthy control group, and the MMP9 level was significantly higher than that of the healthy control group. MMP3 and MMP9 levels correlate with sleep disturbance and cognitive function in PD patients, respectively.

8.
Zool Res ; 43(3): 380-390, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35362675

RESUMO

Maternal sleep deprivation (MSD) is a global public health problem that affects the physical and mental development of pregnant women and their newborns. The latest research suggests that sleep deprivation (SD) disrupts the gut microbiota, leading to neuroinflammation and psychological disturbances. However, it is unclear whether MSD affects the establishment of gut microbiota and neuroinflammation in the newborns. In the present study, MSD was performed on pregnant Sprague-Dawley rats in the third trimester of pregnancy (gestational days 15-21), after which intestinal contents and brain tissues were collected from offspring at different postnatal days (P1, P7, P14, and P56). Based on microbial profiling, microbial diversity and richness increased in pregnant rats subjected to MSD, as reflected by the significant increase in the phylum Firmicutes. In addition, microbial dysbiosis marked by abundant Firmicutes bacteria was observed in the MSD offspring. Furthermore, quantitative real-time polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA) showed that the expression levels of proinflammatory cytokines interleukin 1ß (IL-1ß) and tumor necrosis factor α (TNF-α) were significantly higher in the MSD offspring at adulthood (P56) than in the control group. Through Spearman correlation analysis, IL-1ß and TNF-α were also shown to be positively correlated with Ruminococcus_1 and Ruminococcaceae_UCG-005 at P56, which may determine the microbiota-host interactions in MSD-related neuroinflammation. Collectively, these results indicate that MSD changes maternal gut microbiota and affects the establishment of neonatal gut microbiota, leading to neuroinflammation in MSD offspring. Therefore, understanding the role of gut microbiota during physiological development may provide potential interventions for cognitive dysfunction in MSD-impacted offspring.


Assuntos
Microbioma Gastrointestinal , Doenças dos Roedores , Animais , Disbiose/etiologia , Disbiose/veterinária , Feminino , Microbioma Gastrointestinal/fisiologia , Humanos , Doenças Neuroinflamatórias/veterinária , Gravidez , Ratos , Ratos Sprague-Dawley , Privação do Sono/complicações , Privação do Sono/veterinária
9.
ACS Omega ; 5(33): 21211-21218, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32875257

RESUMO

As a nonaddictive analgesic widely used in clinics, the LD50 of bulleyaconitine A is just only 0.92 mg/kg, which exhibits obvious toxicity. Therefore, 31 new non-natural C19-diterpenoid alkaloids (2a-w, 2'a-e, 3, 4a, and 4b) were designed and synthesized from bulleyaconitine A to develop nonaddictive analgesics with low toxicity. The chemical structures were characterized by 1H NMR, 13C NMR, and high-resolution mass spectrometry (HRMS) spectra. The analgesic activities were evaluated by a hot plate test in mice. At the dosage of 10 mg/kg, six compounds (2d, 2j, 2k, 2m, 2t, 2w) exhibited good analgesic activities (increased pain threshold >100%) with a long duration. Among them, 2w showed the best analgesic activity and the longest duration. Its pain threshold reached 166.35% in 15 min, peaked at 30 min (182.35%), and remained 82.59% even at 60 min.

10.
Fitoterapia ; 146: 104710, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32882337

RESUMO

Three types of new Euphorbia diterpene pseudo-alkaloids possessing 5/6/7/3 (1), 5/6/6/4 (2-5), and 5/7/7/4 (6-7) fused ring skeletons were obtained through an unexpected BF3·Et2O/CH3CN-mediated structural conversion and amination of lathyrane diterpene (Euphorbia factor L1), in which the solution acetonitrile had been introduced into the Euphorbia diterpene as a nitrogen source and tandem amination/oxirane-opening (cyclopropane-opening)/oxa-Michael addition reaction was involved in the conversion. The structures of new Euphorbia diterpene pseudo-alkaloids were elucidated by a combination of spectroscopic data and single crystal X-ray diffraction analysis. The basic skeletons of Euphorbia diterpene pseudo-alkaloids 1 and 2-5 could fall into the structural types of euphoractine B and euphoractine A diterpenes, respectively, suggesting the possible biogenetic pathway relationship between lathyrane diterpene with euphoractines A and B types diterpenes. Pseudo-alkaloids 1-7 did not show any potential cytotoxicity against several tumor cell lines.


Assuntos
Alcaloides Diterpenos/química , Diterpenos/química , Euphorbia/química , Ácidos de Lewis/química , Vias Biossintéticas , Linhagem Celular Tumoral , China , Humanos , Estrutura Molecular , Compostos Fitoquímicos/química , Sementes/química
11.
Front Pediatr ; 8: 303, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32714884

RESUMO

De novo DDX3X variants account for 1%-3% of intellectual disability (ID) in females and have been occasionally reported in males. Here, we report a female patient with severe ID and various other features, including epilepsy, movement disorders, behavior problems, sleep disturbance, precocious puberty, dysmorphic features, and hippocampus atrophy. With the use of family-based exome sequencing, we identified a de novo pathogenic variant (c.1745dupG/p.S583*) in the DDX3X gene. However, our patient did not present hypotonia, which is considered a frequent clinical manifestation associated with DDX3X variants. While hand stereotypies and sleep disturbance have been occasionally associated with the DDX3X spectrum, hippocampus atrophy has not been reported in patients with DDX3X-related ID. The investigation further expands the phenotype spectrum for DDX3X variants with syndromic intellectual disability, which might help to improve the understanding of DDX3X-related intellectual disability or developmental delay.

12.
ACS Omega ; 5(10): 5589-5600, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32201853

RESUMO

According to the activity-structure relationship of the C-13 side chain in paclitaxel or docetaxel, eighteen novel paclitaxel-dehydroepiandrosterone (DHEA) hybrids were designed and synthesized by Pd(II)-catalyzed Suzuki-Miyaura cross-coupling of 17-trifluoromethanesulfonic enolate-DHEA with different aryl boronic acids. The in vitro anticancer activity of the hybrids against a human liver cancer cell line (HepG-2) was evaluated by MTT assay, showing that most of these hybrids possessed moderate antiproliferative activity against the HepG-2 cancer cell line. Among these hybrids, three ones (7b, 7g, and 7i) with ortho-substituents in the phenyl group of the D-ring of DHEA analogues exhibited moderate anticancer activity. The optimal compound 7i showed superior anticancer activity against the HepG-2 cell line with an IC50 value of 26.39 µM.

13.
Nanoscale Res Lett ; 13(1): 300, 2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-30259233

RESUMO

Recently, GaTe and C2N monolayers have been successfully synthesized and show fascinating electronic and optical properties. Such hybrid of GaTe with C2N may induce new novel physical properties. In this work, we perform ab initio simulations on the structural, electronic, and optical properties of the GaTe/C2N van der Waals (vdW) heterostructure. Our calculations show that the GaTe/C2N vdW heterostructure is an indirect-gap semiconductor with type-II band alignment, facilitating an effective separation of photogenerated carriers. Intriguingly, it also presents enhanced visible-UV light absorption compared to its components and can be tailored to be a good photocatalyst for water splitting at certain pH by applying vertical strains. Further, we explore specifically the adsorption and decomposition of water molecules on the surface of C2N layer in the heterostructure and the subsequent formation of hydrogen, which reveals the mechanism of photocatalytic hydrogen production on the 2D GaTe/C2N heterostructure. Moreover, it is found that in-plane biaxial strains can induce indirect-direct-indirect, semiconductor-metal, and type II to type I or type III transitions. These interesting results make the GaTe/C2N vdW heterostructure a promising candidate for applications in next generation of multifunctional optoelectronic devices.

14.
Cancer Biother Radiopharm ; 32(6): 215-219, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28820636

RESUMO

OBJECTIVE: This study aims to explore the clinical efficacy of CpG-based therapy for treating hepatocellular carcinoma (HCC) by skewing polarization toward M1 macrophage from M2. METHODS: Pulmonary metastasis rate, overall survival time, and remission rate of 10 patients with HCC treated with transcatheter arterial chemoembolization (TACE) combined with CpG therapy and 10 age-, gender-, and TNM0-matched patients treated with TACE (control group) were compared. RESULTS: No pulmonary metastasis rate was 70% in the combined treatment group and 40% in the control group, respectively; and the differences between the two groups were statistically significant (p < 0.05). Median overall survival time was 22 months in the combined treatment group, compared with 6.65 months in the control group (p < 0.05). Remission rate in the combined treatment group (70%) was higher than in the control group (30%), but the differences between these two groups were not statistically significant (p > 0.05). CONCLUSION: Compared with TACE, CpG combined with TACE can decrease the pulmonary metastasis rate. This combined therapy can also improve the overall survival time of patients.


Assuntos
Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/terapia , Macrófagos/imunologia , Oligodesoxirribonucleotídeos/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , Polaridade Celular/fisiologia , Quimioembolização Terapêutica , Feminino , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/prevenção & controle , Neoplasias Pulmonares/secundário , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Análise de Sobrevida
15.
Medicine (Baltimore) ; 96(29): e7442, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28723753

RESUMO

BACKGROUND: The association between the tumor necrosis factor-alpha gene (TNF-a) -238G/A polymorphism and the breast cancer has been analyzed in several studies, but the results have been inconclusive. We then performed a meta-analysis to get a precise estimation of the association. METHODS: Eight case-control studies with a total of 37,257 cases and 39,564 controls were identified by searching the ISI Web of Knowledge database and the PubMed database up to August 2014. RESULTS: Overall, no association was found between TNF-alpha-238G/A polymorphism and breast cancer in any of genetic model (additive model OR = 1.06, 95%CI: 0.94-1.21, Pheterogeneity = .02; homozygous model OR = 1.04, 95%CI: 0.83-1.30, Pheterogeneity = .98; dominant model OR = 1.06, 95%CI: 0.92-1.21, Pheterogeneity = .01; recessive model OR = 1.04, 95%CI: 0.83-1.30, Pheterogeneity = .98). Furthermore, no significant association was identified when stratified by ethnicity (Caucasian, Asian). CONCLUSION: This meta-analysis indicated that the TNF-alpha-238G/A polymorphism is not associated with breast cancer risk in the overall population.


Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Fator de Necrose Tumoral alfa/genética , Humanos
16.
Angew Chem Int Ed Engl ; 55(50): 15667-15671, 2016 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-27860043

RESUMO

A unified approach to four different (atisine, ajaconine, denudatine, and hetidine) diterpenoid alkaloid skeletons was developed and applied to the total synthesis of the natural products dihydroajaconine (2, atisine type) and gymnandine (4, denudatine type). The synthesis features a biogenetically inspired strategy that relies on C-H oxidation, aza-pinacol coupling, and aza-Prins cyclization as key steps.

17.
Genes (Basel) ; 7(10)2016 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-27669309

RESUMO

Transposons are often regulated by their hosts, and as a result, there are transposons with several mutations within their host organisms. To gain insight into the patterns of the variations, nucleotide substitutions and indels of transposons were analysed in Chilo suppressalis Walker. The CsuPLE1.1 is a member of the piggyBac-like element (PLE) family, which belongs to the DNA transposons, and the Csu-Ty3 is a member of the Ty3/gypsy family, which belongs to the RNA transposons. Copies of CsuPLE1.1 and Csu-Ty3 were cloned separately from different C. suppressalis individuals, and then multiple sequence alignments were performed. There were numerous single-base substitutions in CsuPLE1.1 and Csu-Ty3, but only a few insertion and deletion mutations. Similarly, in both transposons, the occurring frequencies of transitions were significantly higher than transversions (p ≤ 0.01). In the single-base substitutions, the most frequently occurring base changes were A→G and T→C in both types of transposons. Additionally, single-base substitution frequencies occurring at positions 1, 2 or 3 (pos1, pos2 or pos3) of a given codon in the element transposase were not significantly different. Both in CsuPLE1.1 and Csu-Ty3, the patterns of nucleotide substitution had the same characteristics and nucleotide mutations were biased toward GC. This research provides a perspective on the understanding of transposon mutation patterns.

18.
CNS Neurosci Ther ; 22(7): 617-24, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27079181

RESUMO

BACKGROUND: Parkinson disease (PD) is a neurodegenerative disease characterized by the loss of dopaminergic neurons in the substantia nigra (SN) and diminished dopamine content in the striatum, which is at least partly associated with α-synuclein protein overexpression in these neurons. Recent reports show that 7,8-dihydroxyflavone (DHF), a TrkB agonist, has beneficial effects in animal model of PD. However, it is unclear whether the therapeutic effects of DHF are associated with the expression of α-synuclein. AIMS: In this study, we investigated the protective effects of DHF on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced deficit of motor functions, the loss of dopaminergic neurons and the expression of α-synuclein as well as antioxidative activity in the C57BL/6 mice. RESULTS: Mice were treated with MPTP (30 mg/kg, i.p.) once a day for 5 days to induce dopaminergic neuron death in the SN. DHF (5 mg/kg, i.p.) was administrated once a day from the first day of MPTP injection until 9 days after the last injection of MPTP. Behavioral tests showed that DHF succeeded in ameliorating the impaired motor functions in the MPTP-treated mice. The immunohistochemical assay showed that the amelioration of motor function was accompanied by a reduction in the loss of dopaminergic neurons in the SN and striatum. Western blot analyses showed that DHF prevented the inactivation of TrkB and suppressed α-synuclein overexpression in the SN and striatum following MPTP treatment. Antioxidative activity detection revealed that DHF prevented MPTP-induced reduction in glutathione and total superoxide dismutase activity in the SN and striatum. CONCLUSION: Taken together, these results indicate that DHF treatment may suppress the accumulation of α-synuclein and oxidative stress via activating TrkB and subsequently block the loss of dopaminergic neurons in the SN and striatum, thereby ameliorating MPTP-induced motor deficits in the C57BL/6 mice.


Assuntos
Antiparkinsonianos/uso terapêutico , Flavonas/uso terapêutico , Regulação da Expressão Gênica/efeitos dos fármacos , Intoxicação por MPTP , Estresse Oxidativo/efeitos dos fármacos , alfa-Sinucleína/metabolismo , Análise de Variância , Animais , Morte Celular/efeitos dos fármacos , Modelos Animais de Doenças , Intoxicação por MPTP/tratamento farmacológico , Intoxicação por MPTP/metabolismo , Intoxicação por MPTP/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Movimento/efeitos dos fármacos , Desempenho Psicomotor/efeitos dos fármacos , Receptor trkA/metabolismo , Teste de Desempenho do Rota-Rod , Tirosina 3-Mono-Oxigenase/metabolismo
19.
J Econ Entomol ; 108(3): 1289-97, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26470257

RESUMO

Acetylcholinesterase (AChE) is the target of organophosphate (OP) and carbamate insecticides. Mutations in the AChE gene (ace) leading to decreased insecticide susceptibility is the main resistance mechanism in insects. In this study, two Chilo auricilius acetylcholinesterase genes, designated as Caace1 and Caace2, were cloned using RT-PCR and RACE. Caace1 cDNA is 2534 bp, with ORF of 2082 bp, and it encodes an acetylcholinesterase 1 (CaAChE1) protein comprising a calculated 693 amino acid (aa) residues. Caace2 cDNA contains 2280 bp, with a full-length ORF of 1917 bp, encoding acetylcholinesterase 2 (CaAChE2) comprising a calculated 638 aa residues. At the aa level, CaAChE1 displays the highest similarity (97%) with the Chilo suppressalis AChE1, and CaAChE2 shows the highest similarity with the C. suppressalis AChE2 (99%). From the restriction fragment length polymorphism (RFLP) PCR (RFLP-PCR) analysis, one mutation in Caace1, similar to the ace1 mutation associated with triazophos resistance in C. suppressalis, was detected. Detailed examination of field populations of C. auricilius indicated this resistance mutation in C. auricilius is still quite infrequent. Based on the assay of AChE activity and RFLP-PCR testing, an individual that contains resistance mutation has lower AChE activities, while the individual that does not contain the resistance mutation has higher AChE activities. This study provides a basis for future investigations into the mechanism of OP resistance in C. auricilius, as well as a guidance for C. auricilius control with reasonable choice of pesticides.


Assuntos
Acetilcolinesterase/genética , Proteínas de Insetos/genética , Inseticidas/farmacologia , Mariposas/efeitos dos fármacos , Mariposas/genética , Organotiofosfatos/farmacologia , Triazóis/farmacologia , Acetilcolinesterase/metabolismo , Sequência de Aminoácidos , Animais , China , DNA Complementar/genética , DNA Complementar/metabolismo , Proteínas de Insetos/metabolismo , Resistência a Inseticidas , Larva/efeitos dos fármacos , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Dados de Sequência Molecular , Mariposas/crescimento & desenvolvimento , Mariposas/metabolismo , Filogenia , Alinhamento de Sequência
20.
BMC Mol Biol ; 15: 28, 2014 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-25515331

RESUMO

BACKGROUND: Transposable elements (TEs, transposons) are mobile genetic DNA sequences. TEs can insert copies of themselves into new genomic locations and they have the capacity to multiply. Therefore, TEs have been crucial in the shaping of hosts' current genomes. TEs can be utilized as genetic markers to study population genetic diversity. The rice stem borer Chilo suppressalis Walker is one of the most important insect pests of many subtropical and tropical paddy fields. This insect occurs in all the rice-growing areas in China. This research was carried out in order to find diversity between C. suppressalis field populations and detect the original settlement of C. suppressalis populations based on the piggyBac-like element (PLE). We also aim to provide insights into the evolution of PLEs in C. suppressalis and the phylogeography of C. suppressalis. RESULTS: Here we identify a new piggyBac-like element (PLE) in the rice stem borer Chilo suppressalis Walker, which is called CsuPLE1.1 (GenBank accession no. JX294476). CsuPLE1.1 is transcriptionally active. Additionally, the CsuPLE1.1 sequence varied slightly between field populations, with polymorphic indels (insertion/deletion) and hyper-variable regions including the identification of the 3' region outside the open reading frame (ORF). CsuPLE1.1 insertion frequency varied between field populations. Sequences variation was found between CsuPLE1 copies and varied within and among field populations. Twenty-one different insertion sites for CsuPLE1 copies were identified with at least two insertion loci found in all populations. CONCLUSIONS: Our results indicate that the initial invasion of CsuPLE1 into C. suppressalis occurred before C. suppressalis populations spread throughout China, and suggest that C. suppressalis populations have a common ancestor in China. Additionally, the lower reaches of the Yangtze River are probably the original settlement of C. suppressalis in China. Finally, the CsuPLE1 insertion site appears to be a candidate marker for phylogenetic research of C. suppressalis.


Assuntos
Elementos de DNA Transponíveis , Genes de Insetos , Mariposas/genética , Sequência de Aminoácidos , Distribuição Animal , Animais , Sequência de Bases , China , Evolução Molecular , Mutação INDEL , Dados de Sequência Molecular , Filogenia , Filogeografia , Polimorfismo Genético , Análise de Sequência de DNA , Transcrição Gênica
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