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1.
Zhongguo Gu Shang ; 37(2): 214-8, 2024 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-38425076

RESUMO

Knee osteoarthritis has become one of the common diseases of the elderly, total knee arthroplasty (TKA) is the most effective treatment for end-stage knee osteoarthritis at present. In TKA, the effective restoration of the lower extremity alignment is one of the key factors for the success of the operation, which greatly affects the postoperative clinical effect and prosthesis survival rate of patients. Mechanical alignment is a TKA alignment method which is first proposed, recognized and widely used in TKA. In recent years, with the in-depth research on the lower limb alignment and the rapid development of computer technology, the alignment technology in TKA has realized the transformation from "unified" to "individualized", two-dimensional to three-dimensional. New alignment methods, such as adjusted mechanical alignment, anatomic alignment, kinematic alignment, inverse kinematic alignment, restricted kinematic alignment and functional alignment have been proposed to provide surgeons with more choices. However, there is no conclusion on which alignment method is the best choice. This paper summarizes the current research status, advantages and disadvantages of various alignment methods in TKA, and aims to provide some reference for the selection of alignment methods in TKA.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Osteoartrite do Joelho , Humanos , Idoso , Artroplastia do Joelho/efeitos adversos , Osteoartrite do Joelho/cirurgia , Articulação do Joelho/cirurgia , Extremidade Inferior/cirurgia , Fenômenos Biomecânicos
2.
Curr Med Sci ; 43(3): 551-559, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37115398

RESUMO

OBJECTIVE: To compare survival outcomes between primary radical surgery and primary radiation in early cervical cancer. METHODS: Patient information was extracted from the Surveillance, Epidemiology, and Results database. Patients diagnosed with early cervical cancer of stage T1a, T1b, and T2a (American Joint Committee on Cancer, 7th edition) from 1998 to 2015 were included in this study after propensity score matching. Overall survival (OS) was analyzed using the Kaplan-Meier method. RESULTS: Among the 4964 patients included in the study, 1080 patients were identified as having positive lymph nodes (N1), and 3884 patients were identified as having negative lymph nodes (N0). Patients with primary surgery had significantly longer 5-year OS than those with primary radiotherapy in both the N1 group (P<0.001) and N0 group (P<0.001). In the subgroup analysis, similar results were found in patients with positive lymph nodes of stage T1a (100.0% vs. 61.1%), T1b (84.1% vs. 64.3%), and T2a (74.4% vs. 63.8%). In patients with T1b1 and T2a1, primary surgery resulted in longer OS than primary radiation, but not in patients with T1b2 and T2a2. In multivariate analysis, the primary treatment was identified as an independent prognostic factor in both N1 and N0 patients (HRN1=2.522, 95% CI=1.919-3.054, PN1<0.001; HRN0=1.895, 95% CI=1.689-2.126, PN0<0.001). CONCLUSION: In early cervical cancer stage T1a, T1b1, and T2a1, primary surgery may result in longer OS than primary radiation for patients with and without lymph node metastasis.


Assuntos
Linfonodos , Neoplasias do Colo do Útero , Feminino , Humanos , Linfonodos/cirurgia , Linfonodos/patologia , Metástase Linfática/patologia , Estadiamento de Neoplasias , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/cirurgia , Neoplasias do Colo do Útero/patologia
3.
Virulence ; 14(1): 2171691, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36694288

RESUMO

Polydnaviruses (PDVs), obligatory symbionts with parasitoid wasps, function as host immune suppressors and growth and development regulator. PDVs can induce host haemocyte apoptosis, but the underlying mechanism remains largely unknown. Here, we provided evidence that, during the early stages of parasitism, the activated Cotesia vestalis bracovirus (CvBV) reduced the overall number of host haemocytes by inducing apoptosis. We found that one haemocyte-highly expressed CvBV gene, CvBV-26-4, could induce haemocyte apoptosis. Further analyses showed that CvBV-26-4 has four homologs from other Cotesia bracoviruses and BV from wasps in the genus Glyptapanteles, and all four of them possessed a similar structure containing 3 copies of a well-conserved motif (Gly-Tyr-Pro-Tyr, GYPY). Mass spectrometry analysis revealed that CvBV-26-4 was secreted into plasma by haemocytes and then degraded into peptides that induced the apoptosis of haemocytes. Moreover, ectopic expression of CvBV-26-4 caused fly haemocyte apoptosis and increased the susceptibility of flies to bacteria. Based on this research, a new family of bracovirus genes, Bracovirus apoptosis-inducing proteins (BAPs), was proposed. Furthermore, it was discovered that the development of wasp larvae was affected when the function of CvBV BAP was obstructed in the parasitized hosts. The results of our study indicate that the BAP gene family from the bracoviruses group is crucial for immunosuppression during the early stages of parasitism.


Assuntos
Mariposas , Polydnaviridae , Vespas , Animais , Polydnaviridae/genética , Hemócitos , Larva , Apoptose
4.
Viruses ; 15(1)2022 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-36680096

RESUMO

Polydnavirus (PDV) is a parasitic factor of endoparasitic wasps and contributes greatly to overcoming the immune response of parasitized hosts. Protein tyrosine phosphatases (PTPs) regulate a wide variety of biological processes at the post-transcriptional level in mammals, but knowledge of PDV PTP action during a parasitoid−host interaction is limited. In this study, we characterized a PTP gene, CvBV_12-6, derived from Cotesia vestalis bracovirus (CvBV), and explored its possible regulatory role in the immune response of the host Plutella xylostella. Our results from qPCR show that CvBV_12-6 was highly expressed in hemocytes at an early stage of parasitization. To explore CvBV_12-6 function, we specifically expressed CvBV_12-6 in Drosophila melanogaster hemocytes. The results show that Hml-Gal4 > CvBV_12-6 suppressed the phenoloxidase activity of hemolymph in D. melanogaster, but exerted no effect on the total count or the viability of the hemocytes. In addition, the Hml-Gal4 > CvBV_12-6 flies exhibited decreased antibacterial abilities against Staphylococcus aureus. Similarly, we found that CvBV_12-6 significantly suppressed the melanization of the host P. xylostella 24 h post parasitization and reduced the viability, but not the number, of hemocytes. In conclusion, CvBV_12-6 negatively regulated both cellular and humoral immunity in P. xylostella, and the related molecular mechanism may be universal to insects.


Assuntos
Mariposas , Polydnaviridae , Animais , Sequência de Aminoácidos , Drosophila melanogaster/virologia , Monofenol Mono-Oxigenase/metabolismo , Mariposas/virologia , Polydnaviridae/genética , Polydnaviridae/metabolismo , Proteínas Tirosina Fosfatases/genética , Proteínas Tirosina Fosfatases/metabolismo , Interações Hospedeiro-Patógeno
5.
Curr Med Sci ; 42(1): 185-191, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34669113

RESUMO

OBJECTIVE: The present study was designed to evaluate the effects of adjuvant chemotherapy (CT) vs. radiotherapy (RT, alone or combined with CT) on the prognosis of patients with high-risk, early-stage (stage I and stage II) endometrioid endometrial carcinoma. METHODS: This single-center retrospective clinical study was conducted in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology between 2010 and 2019. In the present study, endometrioid endometrial carcinoma patients, who underwent total hysterectomy and bilateral salpingo-oophorectomy followed by postoperative adjuvant CT or RT (alone or combined with CT), and were diagnosed with stage IA grade 2/3 with lymph-vascular space invasion (LVSI), and stage IB with two or more uterine risks, including old age, histological grade 2 or 3, LVSI and stage II, were included. According to the postoperative adjuvant therapy, all eligible patients were divided into two groups: CT group and RT (RT±CT) group. The primary objective was to investigate overall survival (OS) and disease-free survival (DFS) between the CT and RT groups. Grade 3 or worse adverse events were also presented in the present study. RESULTS: A total of 145 eligible patients were included. Among these patients, 97 patients underwent adjuvant CT and 48 patients underwent adjuvant RT (RT±CT). The median follow-up was 47.2 months, and the five-year OS rate was 92.7% in the CT group and 88.6 % in the RT group [hazard ratio (HR): 0.81, 95% confidence interval (CI): 0.22-2.99). The 5-year DFS rate for the two groups was 85.7% and 80.2%, respectively (HR: 0.82, 95% CI: 0.33-2.05). The cumulative incidence of local-regional disease recurrence at 60 months of follow-up was 6.2% in the CT group and 6.3% in the RT group (HR=1.11; 95%CI: 0.28-4.35). The cumulative incidence of distant recurrence at 60 months of follow-up was 5.2% in the CT group and 10.4% in the RT group (HR=0.65; 95%CI: 0.19-2.24). Both groups of patients were well-tolerant, and the only grade 3 or worse adverse events were neutropenia and thrombocytopenia. CONCLUSION: There was no difference in efficacy for adjuvant CT or adjuvant RT (RT±CT) in high-risk, early-stage endometrioid endometrial carcinoma. CT exhibited a trend of reducing the distant relapse, although there was no significant difference, when compared with adjuvant RT (RT±CT).


Assuntos
Carcinoma Endometrioide/tratamento farmacológico , Carcinoma Endometrioide/radioterapia , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/radioterapia , Estadiamento de Neoplasias , Avaliação de Resultados em Cuidados de Saúde , Adulto , Idoso , Carcinoma Endometrioide/mortalidade , Carcinoma Endometrioide/cirurgia , Quimiorradioterapia , Quimioterapia Adjuvante , Neoplasias do Endométrio/mortalidade , Neoplasias do Endométrio/cirurgia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Risco
6.
Insect Sci ; 28(5): 1354-1368, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32761881

RESUMO

Odorant-binding proteins (OBPs) are crucial in insect's olfactory perception, which participate in the initial step of odorant molecules transporting from the external environment to olfactory receptor neurons. To better understand the roles for OBPs in olfactory perception in Cotesia vestalis, a solitary larval endoparasitoid of diamondback moth, Plutella xylostella, we have comprehensively screened the genome of C. vestalis, and obtained 20 CvesOBPs, including 18 classic OBPs and two minus-C OBPs. Motif-pattern analysis indicates that the motifs of C. vestalis OBPs are highly conserved in Hymenoptera. The results of tissue expression analysis show that five OBPs (CvesOBP1/11/12/14/16) are highly expressed in male antennae, whereas six other OBP genes (CvesOBP7/8/13/17/18/19) are significantly transcriptionally enriched in female antennae. The results of RNA interference experiments for three most highly expressed OBP genes (CvesOBP17/18/19) in female antennae demonstrate that they are likely involved in parasitic processes of female wasps, as the wasps take a longer time to target the hosts when they are knocked down.


Assuntos
Proteínas de Insetos , Receptores Odorantes , Vespas , Animais , Feminino , Proteínas de Insetos/genética , Larva , Masculino , Mariposas/parasitologia , Filogenia , Receptores Odorantes/genética , Vespas/genética
7.
Insect Sci ; 28(6): 1567-1581, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33155403

RESUMO

Polydnaviruses (PDVs) are obligatory symbionts of parasitoid wasps and play an important role in suppressing host immune defenses. Although PDV genes that inhibit host melanization are known in Microplitis bracovirus, the functional homologs in Cotesia bracoviruses remain unknown. Here, we find that Cotesia vestalis bracovirus (CvBV) can inhibit hemolymph melanization of its host, Plutella xylostella larvae, during the early stages of parasitization, and that overexpression of highly expressed CvBV genes reduced host phenoloxidase activity. Furthermore, CvBV-7-1 in particular reduced host phenoloxidase activity within 12 h, and the injection of anti-CvBV-7-1 antibody increased the melanization of parasitized host larvae. Further analyses showed that CvBV-7-1 and three homologs from other Cotesia bracoviruses possessed a C-terminal leucine/isoleucine-rich region and had a similar function in inhibiting melanization. Therefore, a new family of bracovirus genes was proposed and named as C-terminal Leucine/isoleucine-rich Protein (CLP). Ectopic expression of CvBV-7-1 in Drosophila hemocytes increased susceptibility to bacterial repression of melanization and reduced the melanotic encapsulation of parasitized D. melanogaster by the parasitoid Leptopilina boulardi. The formation rate of wasp pupae and the eclosion rate of C. vestalis were affected when the function of CvBV-7-1 was blocked. Our findings suggest that CLP genes from Cotesia bracoviruses encoded proteins that contain a C-terminal leucine/isoleucine-rich region and function as melanization inhibitors during the early stage of parasitization, which is important for successful parasitization.


Assuntos
Genes Virais , Melaninas , Mariposas , Pigmentação , Polydnaviridae , Animais , Drosophila melanogaster/parasitologia , Drosophila melanogaster/virologia , Hemolinfa , Interações Hospedeiro-Parasita , Isoleucina , Larva , Leucina , Monofenol Mono-Oxigenase , Mariposas/parasitologia , Mariposas/virologia , Polydnaviridae/genética , Vespas/virologia
8.
Front Microbiol ; 11: 608346, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33519757

RESUMO

Polydnaviruses (PDVs), classified into two genera, bracoviruses (BVs) and ichnoviruses (IVs), are large, double-stranded DNA viruses, which are beneficial symbionts of parasitoid wasps. PDVs do not replicate in their infected lepidopteran hosts. BV circles have been demonstrated to be integrated into host genomic DNA after natural parasitization. However, the integrations of IV circles in vivo remain largely unknown. Here, we analyzed the integration of Diadegma semiclausum ichnovirus (DsIV) in the genomic DNA of parasitized Plutella xylostella hemocytes. We found that DsIV circles are present in host hemocytes with non-integrated and integrated forms. Moreover, DsIV integrates its DNA circles into the host genome by two distinct strategies, conservatively, and randomly. We also found that four conserved-broken circles share similar motifs containing two reverse complementary repeats at their breaking sites, which were host integration motifs (HIMs). We also predicted HIMs of eight circles from other ichnoviruses, indicating that a HIM-mediated specific mechanism was conserved in IV integrations. Investigation of DsIV circle insertion sites of the host genome revealed the enrichment of microhomologies between the host genome and the DsIV circles at integration breakpoints. These findings will deepen our understanding of the infections of PDVs, especially IVs.

9.
Sci Rep ; 9(1): 11949, 2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31420562

RESUMO

The rice root-knot nematode, Meloidogyne graminicola, is a serious pest in most rice-growing countries. Usually, nematodes employ antioxidants to counteract the harm of reactive oxygen species (ROS) and facilitate their infection. Here the gene encoding M. graminicola protein disulphide isomerase (MgPDI) was identified. The deduced protein is highly conserved in the putative active-site Cys-Gly-His-Cys. In situ hybridization showed that MgPDI was specifically localized within esophageal glands of pre-parasitic second stage juveniles (J2s). MgPDI was significantly up-regulated in the late parasitic J2s. Characterization of the recombinant protein showed that the purified MgPDI exhibited similar activities to other oxidases/isomerases such as the refolding of the scrambled RNase and insulin disulfide reductase and the protection of plasmid DNA and living cells from ROS damage. In addition, silencing of MgPDI by RNA interference in the pre-parasitic J2s lowered their multiplication factor. MgPDI expression was up-regulated in the presence of exogenous H2O2, whereas MgPDI silencing resulted in an increase in mortality under H2O2 stress. MgPDI is localized in the apoplast when transient expression in Nicotiana benthamiana leaves. The results indicated that MgPDI plays important roles in the reproduction and pathogenicity of M. graminicola and it also contributes to protecting nematodes from exogenous H2O2 stress.


Assuntos
Proteínas de Helminto/química , Peróxido de Hidrogênio/química , Oryza/parasitologia , Isomerases de Dissulfetos de Proteínas/química , Tylenchoidea/química , Sequência de Aminoácidos , Animais , Domínio Catalítico , Sequência Conservada , Expressão Gênica , Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Cinética , Modelos Moleculares , Estresse Oxidativo , Doenças das Plantas/parasitologia , Raízes de Plantas/parasitologia , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Isomerases de Dissulfetos de Proteínas/genética , Isomerases de Dissulfetos de Proteínas/metabolismo , Domínios e Motivos de Interação entre Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Tylenchoidea/enzimologia , Tylenchoidea/patogenicidade
10.
Exp Appl Acarol ; 77(4): 545-554, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30997606

RESUMO

The acaricide bifenazate acts as complex III inhibitor whereas cyenopyrafen and SYP-9625 act as complex II inhibitors. All these acaricides are commonly used to control two-spotted spider mite (TSSM), Tetranychus urticae Koch. We examined field-evolved and laboratory-selected resistance of TSSM to these three acaricides and determined cross-resistance among them. Six field populations of TSSM showed low levels of resistance to bifenazate with resistance ratios ranging from 2.20 to 10.65 compared to a susceptible strain. SYP-9625, structurally similar to cyenopyrafen, showed slightly higher activity to TSSMs but significant cross-resistance in both field populations and a laboratory-selected strain by SYP-9625. However, low levels of resistance to these two chemicals were found in field populations even when used for short time periods. Cross-resistance was not found between bifenazate and Complex II inhibitors, cyenopyrafen and SYP-9625, in both field populations and the laboratory-selected strain. Field-evolved resistance of TSSM to the tested acaricides is still low and should be delayed by the implementation of resistance management practices. Cross-resistance between cyenopyrafen and SYP-9625 is obvious, so they should not be used together in resistance management strategies based on mode of action rotation.


Assuntos
Acaricidas/farmacologia , Evolução Biológica , Resistência a Medicamentos , Tetranychidae/efeitos dos fármacos , Acrilonitrila/análogos & derivados , Acrilonitrila/farmacologia , Animais , Carbamatos/farmacologia , China , Hidrazinas/farmacologia , Pirazóis/farmacologia , Tetranychidae/fisiologia
11.
Microb Biotechnol ; 12(3): 528-543, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30884189

RESUMO

Vermicomposting using black soldier fly (BSF) larvae (Hermetia illucens) has gradually become a promising biotechnology for waste management, but knowledge about the larvae gut microbiome is sparse. In this study, 16S rRNA sequencing, SourceTracker, and network analysis were leveraged to decipher the influence of larvae gut microbiome on food waste (FW) biodegradation. The microbial community structure of BSF vermicompost (BC) changed greatly after larvae inoculation, with a peak colonization traceable to gut bacteria of 66.0%. The relative abundance of 11 out of 21 metabolic function groups in BC were significantly higher than that in natural composting (NC), such as carbohydrate-active enzymes. In addition, 36.5% of the functional genes in BC were significantly higher than those in NC. The changes of metabolic functions and functional genes were significantly correlated with the microbial succession. Moreover, the bacteria that proliferated in vermicompost, including Corynebacterium, Vagococcus, and Providencia, had strong metabolic abilities. Systematic and complex interactions between the BSF gut and BC bacteria occurred over time through invasion, altered the microbial community structure, and thus evolved into a new intermediate niche favourable for FW biodegradation. The study highlights BSF gut microbiome as an engine for FW bioconversion, which is conducive to bioproducts regeneration from wastes.


Assuntos
Compostagem/métodos , Dípteros/metabolismo , Dípteros/microbiologia , Alimentos , Microbioma Gastrointestinal , Animais , Biotransformação , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Larva/metabolismo , Larva/microbiologia , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Gerenciamento de Resíduos/métodos
12.
ACS Appl Mater Interfaces ; 11(14): 13123-13133, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30888144

RESUMO

Mitochondria play a critical role in tumorigenesis. Targeting mitochondria and disturbing related events have been emerging as a promising way for chemotherapy. In this work, two binuclear rhenium(I) tricarbonyl complexes of the general formula [Re2(CO)6(dip)2L](PF6)2 (dip = 4,7-diphenyl-1,10-phenanthroline; L = 4,4'-azopyridine (ReN) or 4,4'-dithiodipyridine (ReS)) were synthesized and characterized. ReN and ReS can react with glutathione (GSH). They exhibit good in vitro anticancer activity against cancer cell lines screened. Besides, they can target mitochondria, cause oxidative stress, and disturb GSH metabolism. Both ReN and ReS can induce necroptosis and caspase-dependent apoptosis simultaneously. We also demonstrate that ReN and ReS can inhibit tumor growth in nude mice bearing carcinoma xenografts. Our study shows the potential of Re(I) complexes as chemotherapeutic agents to kill cancer cells via a mitochondria-to-cellular redox strategy.


Assuntos
Carcinogênese/efeitos dos fármacos , Carcinoma/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Rênio/administração & dosagem , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Carcinoma/patologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/administração & dosagem , Complexos de Coordenação/química , Glutationa/antagonistas & inibidores , Glutationa/metabolismo , Humanos , Camundongos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/química , Rênio/química , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Huan Jing Ke Xue ; 40(1): 11-23, 2019 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-30628255

RESUMO

The effects of emission reductions of key sources (eight key industries and transportation) on the PM2.5 concentrations in the Yangtze River Delta (YRD) were investigated using the weather research forecast-chemistry (WRF-Chem) model in 2013 combined with two normal and enhanced emission reduction scenarios. The SO2, NOx, PM2.5, and NMVOC emissions in the YRD decrease by 36.3%, 26.3%, 32.0%, and 14.6% and by 51.4%, 39.6%, 37.6%, and 28.4% under the normal and enhanced emission reduction scenarios, respectively. The simulation results show that the annual mean PM2.5 concentrations over the national environmental monitoring sites in the YRD decline by 1.4-26.7 µg·m-3 and 2.1-32.3 µg·m-3, reflecting a decrease of 2.7%-23.1% and 3.9%-27.5%, under the two emission reduction scenarios, respectively. The nitrate in secondary inorganic aerosols contributes the most to the reduction of the annual mean PM2.5 concentration. The seasonal variation characteristics of the PM2.5 and secondary inorganic aerosol concentrations reflect that the smallest and largest declining rates occur in winter and summer, respectively. With increasing emission reduction, the declining rates of PM2.5 and the secondary inorganic aerosol concentrations in summer increase more compared with those in other seasons, resulting in a greater seasonal variation of the rates. The PM2.5 concentrations decrease by~20% in Shanghai and the Jiangsu Province under the enhanced emission scenario in summer. The analysis of the atmospheric oxidation shows that the atmospheric oxidation capacity is enhanced to different degrees by emission reductions of key sources in all seasons; it is further enhanced with increasing emission reduction. The enhanced oxidation capacity favors the formation of secondary PM2.5, thereby hindering the reduction of the PM2.5 concentration. The strongest hindrance occurs in winter, resulting in the worst PM2.5 pollution improvement. The atmospheric oxidation capacity is less affected by emission reductions of key sources in summer, making PM2.5 pollution improvement most effective. Furthermore, the negative effects of the enhancement of the atmospheric oxidation capacity on the reduction of the PM2.5 concentration in spring and autumn cannot be ignored.

14.
Ecotoxicology ; 27(6): 742-751, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29951794

RESUMO

Chemical control is important in the management of the tobacco whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). Susceptibility of B. tabaci to insecticides may vary among different developmental stages and geographical populations. In this study, we examined toxicity of seven commonly-used insecticides to B. tabaci MED in four field populations from China. Avermectin has high level of toxicity to all stages of B. tabaci MED in all four populations. Cyantraniliprole and sulfoxaflor have high toxicity to adults. Spirotetramat, cyantraniliprole and flonicamid have high toxicity to nymphs but not adults. Acetamiprid, cyantraniliprole and sulfoxaflor have high toxicity to eggs. However, the relative toxicity of B. tabaci MED to these chemicals varied across different populations, with little consistency in population differences across developmental stages. Our findings together with some instances where LC95 values were higher than field recommended dosages indicate field-evolved resistance to insecticides (such as thiamethoxam and sulfoxaflor) and stage-specific mechanisms that will influence effective control of B. tabaci MED by insecticides.


Assuntos
Hemípteros/efeitos dos fármacos , Inseticidas/farmacologia , Animais , China , Hemípteros/crescimento & desenvolvimento , Ninfa/efeitos dos fármacos , Ninfa/crescimento & desenvolvimento
15.
Nat Commun ; 9(1): 2205, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29880839

RESUMO

Parasitic wasps produce several factors including venom, polydnaviruses (PDVs) and specialized wasp cells named teratocytes that benefit the survival of offspring by altering the physiology of hosts. However, the underlying molecular mechanisms for the alterations remain unclear. Here we find that the teratocytes of Cotesia vestalis, an endoparasitoid of the diamondback moth Plutella xylostella, and its associated bracovirus (CvBV) can produce miRNAs and deliver the products into the host via different ways. Certain miRNAs in the parasitized host are mainly produced by teratocytes, while the expression level of miRNAs encoded by CvBV can be 100-fold greater in parasitized hosts than non-parasitized ones. We further show that one teratocyte-produced miRNA (Cve-miR-281-3p) and one CvBV-produced miRNA (Cve-miR-novel22-5p-1) arrest host growth by modulating expression of the host ecdysone receptor (EcR). Altogether, our results show the first evidence of cross-species regulation by miRNAs in animal parasitism and their possible function in the alteration of host physiology during parasitism.


Assuntos
Interações Hospedeiro-Parasita/genética , MicroRNAs/fisiologia , Mariposas/crescimento & desenvolvimento , Parasitos/genética , Polydnaviridae/genética , Vespas/genética , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Larva/genética , Larva/virologia , Mariposas/parasitologia , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Vespas/virologia
16.
J Insect Physiol ; 107: 197-203, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29626507

RESUMO

Laccase (EC 1.10.3.2) is a phenoloxidase found in many insect species. The Laccase 1 gene from Plutella xylostella (PxLac1) was cloned, and its expression patterns and functions were determined using qPCR and RNAi methods. The results showed that the expression levels of PxLac1 were consistently high in all larval stages, and the most abundant was in the midgut during the 4th instar stage. Moreover, the expression of PxLac1 was up-regulated in response to bacterial infection, and decreased 24 h after being parasitized by Cotesia vestalis. Further analyses indicated that the effect of parasitization on PxLac1 was induced by active C. vestalis Bracovirus (CvBV). Haemocyte-free hemolymph phenoloxidase (PO) activity was suppressed when PxLac1 was treated with RNAi. Our results provide evidence for a connection between the Laccase 1 gene and insect immunity, and revealed that parasitoid polydnavirus suppresses host PO activity via PxLac1 regulation.


Assuntos
Proteínas de Insetos/genética , Lacase/genética , Mariposas/genética , Sequência de Aminoácidos , Animais , Feminino , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Lacase/química , Lacase/metabolismo , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Masculino , Mariposas/crescimento & desenvolvimento , Mariposas/metabolismo , Filogenia , Pupa/genética , Pupa/crescimento & desenvolvimento , Pupa/metabolismo , Alinhamento de Sequência
17.
Exp Appl Acarol ; 75(2): 143-153, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29594845

RESUMO

To develop a new control method for the two-spotted spider mite (TSSM), Tetranychus urticae, we investigated the effect of controlled atmospheres of carbon dioxide (CO2) on TSSM mortality under different concentrations and treatment periods, and evaluated the impact of treatments on seedlings of five host plants of TSSM. Egg hatching rate of TSSM was reduced to 37.7, 5.4 or 0% after 24 h treatment involving concentrations of 16.7, 33.3 or 50%, respectively. Mobile stages (nymphs and adult) of TSSM were completely controlled after 24 h treatment at concentrations higher than 33.3%. After 4 h at concentrations of 33.3 or 50%, 1st-day survival rate for all mobile stages was 45.3 or 36.0%, respectively, whereas after 8 or 16 h treatments, all values were decreased to zero. Seedlings of four major host plants of TSSM (cucumber, eggplant, rape, green peppers) were damaged to varying degrees after 24 h at the three concentrations, but strawberry, another host plant, was not damaged. Cucumber suffered the most serious damage, resulting in wilting and death. In conclusion, controlled atmospheres of CO2 can kill TSSM, particularly at high concentrations and with long treatment times. It can be used to control TSSM on strawberry, but should be used cautiously on other host plants.


Assuntos
Acaricidas , Dióxido de Carbono , Produtos Agrícolas , Tetranychidae , Controle de Ácaros e Carrapatos , Animais , Produtos Agrícolas/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento
18.
Mol Med Rep ; 17(1): 1083-1092, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29115488

RESUMO

General anesthesia is widely used in pediatric surgery, although the influence of general anesthesia on cerebellar information transmission and motor function is unclear. In the present study, neonatal mice received repeated inhalation of sevoflurane, and electrophysiological alterations in Purkinje cells (PCs) and the development of motor functions were detected. In addition, γ­aminobutyric acidA receptor ε (GABAA­R ε) subunit knockout mice were used to investigate the mechanism of action of sevoflurane on cerebellar function. In the neonatal mice, the field potential response of PCs induced by sensory stimulation and the motor function indices were markedly inhibited by sevoflurane, and the inhibitory effect was positively associated with the number of repetitions of anesthesia. In additional the GABAA­R ε subunit level of PCs was promoted by sevoflurane in a dose­dependent manner, and the inhibitory effects of sevoflurane on PC field potential response and motor function were alleviated in GABAA­R ε subunit knockout mice. The GABAA­R ε subunit was activated by sevoflurane, leading to inhibition of sensory information transmission in the cerebellar cortex, field potential responses of PCs and the development of cerebellar motor function. The present study provided experimental evidence for the safe usage of sevoflurane in clinical anesthesia, and suggested that GABAA­R ε subunit antagonists may be considered for combined application with general anesthesia with repeated inhalation of sevoflurane, for adverse effect prevention in the clinic.


Assuntos
Anestésicos Inalatórios/administração & dosagem , Éteres Metílicos/administração & dosagem , Células de Purkinje/efeitos dos fármacos , Células de Purkinje/fisiologia , Receptores de GABA-A/metabolismo , Transmissão Sináptica/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Comportamento Animal , Córtex Cerebelar/efeitos dos fármacos , Córtex Cerebelar/fisiologia , Feminino , Locomoção/efeitos dos fármacos , Camundongos , Camundongos Knockout , Receptores de GABA-A/genética , Sevoflurano
19.
Evol Appl ; 10(4): 391-401, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28352298

RESUMO

Historical invasion scenarios based on observational records are usually incomplete and biased, but these can be supplemented by population genetic data. The western flower thrips (WFT), Frankliniella occidentalis, invaded China in the last 13 years and has rapidly become one of the most serious pests in the country. To assess whether this invasion involved a single event or multiple events, we examined patterns of genetic diversity and population structure of WFT across 12 Chinese populations and a native US population based on mitochondrial DNA and/or 18 microsatellite loci. The average allelic richness and haplotype diversity in Chinese populations were significantly lower than in a population from its native range. The distribution of mitochondrial haplotypes suggested multiple independent invasions of WFT into China, including two invasions into the Beijing region. Based on microsatellite data, two distinct clusters were identified, with both of them splitting further into two clusters; in the Beijing region, the microsatellite data also provided evidence for two introductions. Both the absence of isolation by distance and the fact that distant populations were similar genetically suggest patterns of WFT movement linked to human activities. Our study therefore suggests multiple introductions of WFT into China and human-assisted spread.

20.
Sci Rep ; 6: 26967, 2016 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-27254821

RESUMO

Some endoparasitoid wasps lay eggs that produce cells called teratocytes. In this study, we sequenced and analyzed the transcriptome of teratocytes from the solitary endoparasitoid Cotesia vestalis (Braconidae), which parasitizes larval stage Plutella xylostella (Plutellidae). Results identified many teratocyte transcripts with potential functions in affecting host immune defenses, growth or metabolism. Characterization of teratocyte-secreted venom-like protein 8 (TSVP-8) indicated it inhibits melanization of host hemolymph in vitro, while two predicted anti-microbial peptides (CvT-def 1 and 3) inhibited the growth of bacteria. Results also showed the parasitized hosts lacking teratocytes experienced higher mortality after immune challenge by pathogens than hosts with teratocytes. Taken together, these findings indicate that C. vestalis teratocytes secrete products that alter host immune functions while also producing anti-microbial peptides with functions that help protect the host from infection by other organisms.


Assuntos
Proteínas de Insetos/genética , Vespas/genética , Animais , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/imunologia , Defensinas/genética , Defensinas/metabolismo , Defensinas/farmacologia , Resistência à Doença , Escherichia coli/efeitos dos fármacos , Escherichia coli/imunologia , Regulação da Expressão Gênica , Imunidade Inata , Proteínas de Insetos/metabolismo , Proteínas de Insetos/farmacologia , Larva/microbiologia , Larva/parasitologia , Testes de Sensibilidade Microbiana , Mariposas/microbiologia , Mariposas/parasitologia , Sinais Direcionadores de Proteínas , Transcriptoma , Venenos de Vespas/genética , Venenos de Vespas/metabolismo , Vespas/citologia , Vespas/metabolismo , Vespas/microbiologia
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