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1.
Plant Biotechnol J ; 21(2): 391-404, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36345605

RESUMO

China is the world's second-largest maize producer and consumer. In recent years, the invasive fall armyworm Spodoptera frugiperda (J.E. Smith) has adversely affected maize productivity and compromised food security. To mitigate pest-inflicted food shortages, China's Government issued biosafety certificates for two genetically modified (GM) Bt maize hybrids, Bt-Cry1Ab DBN9936 and Bt-Cry1Ab/Cry2Aj Ruifeng 125, in 2019. Here, we quantitatively assess the impact of both Bt maize hybrids on pest feeding damage, crop yield and food safety throughout China's maize belt. Without a need to resort to synthetic insecticides, Bt maize could mitigate lepidopteran pest pressure by 61.9-97.3%, avoid yield loss by 16.4-21.3% (range -11.9-99.2%) and lower mycotoxin contamination by 85.5-95.5% as compared to the prevailing non-Bt hybrids. Yield loss avoidance varied considerably between experimental sites and years, as mediated by on-site infestation pressure and pest identity. For either seed mixtures or block refuge arrangements, pest pressure was kept below established thresholds at 90% Bt maize coverage in Yunnan (where S. frugiperda was the dominant species) and 70% Bt maize coverage in other sites dominated by Helicoverpa armigera (Hübner) and Ostrinia furnacalis (Guenée). Drawing on experiences from other crop/pest systems, Bt maize in se can provide area-wide pest management and thus, contribute to a progressive phase-down of chemical pesticide use. Hence, when consciously paired with agroecological and biodiversity-based measures, GM insecticidal crops can ensure food and nutrition security, contribute to the sustainable intensification of China's agriculture and reduce food systems' environmental footprint.


Assuntos
Inseticidas , Mariposas , Animais , Zea mays/genética , Endotoxinas/genética , Toxinas de Bacillus thuringiensis , Plantas Geneticamente Modificadas/genética , Proteínas Hemolisinas/genética , Proteínas de Bactérias/genética , China , Inseticidas/farmacologia , Controle Biológico de Vetores , Inocuidade dos Alimentos
2.
Int J Mol Sci ; 24(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37108751

RESUMO

Understanding plant-insect interactions requires the uncovering of the host plant use of insect herbivores, but such information is scarce for most taxa, including nocturnal moth species, despite their vital role as herbivores and pollinators. In this study, we determined the plant species visited by an important moth species, Spodoptera exigua, by analyzing attached pollen on migratory individuals in Northeast China. Pollen grains were dislodged from 2334 S. exigua long-distance migrants captured between 2019 and 2021 on a small island in the center of the Bohai Strait, which serves as a seasonal migration pathway for this pest species, and 16.1% of the tested moths exhibited pollen contamination, primarily on the proboscis. Subsequently, 33 taxa from at least 23 plant families and 29 genera were identified using a combination of DNA barcoding and pollen morphology, primarily from the Angiosperm, Dicotyledoneae. Moreover, the sex, inter-annual, and seasonal differences in pollen adherence ratio and pollen taxa were revealed. Notably, compared to previously reported pollen types found on several other nocturnal moths, we found that almost all of the above 33 pollen taxa can be found in multiple nocturnal moth species, providing another important example of conspecific attraction. Additionally, we also discussed the indicative significance of the pollen present on the bodies of migratory individuals for determining their migratory route. Overall, by delineating the adult feeding and pollination behavior of S. exigua, we advanced our understanding of the interactions of the moths with their host plants, and its migration pattern, as well as facilitated the design of (area-wide) management strategies to preserve and optimize ecosystem services that they provide.


Assuntos
Magnoliopsida , Mariposas , Animais , Spodoptera , Polinização , Ecossistema , Pólen/genética , Mariposas/genética , Plantas , Ásia Oriental
3.
Mol Ther ; 29(2): 775-787, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33091613

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) represents one of the deadliest forms of cancer with very few available therapeutic options. We previously reported that an engineered human enzyme, cyst(e)inase, which degrades L-cysteine (L-Cys) and cystine, inhibits growth of multiple cancer cells, including PDAC both in vitro and in vivo. Here, we show that cyst(e)inase treatment leads to increased clustered oxidative DNA damage, DNA single-strand breaks, apurinic/apyrimidinic sites, and DNA double-strand breaks (DSBs) in PDAC cells sensitive to intracellular depletion of L-Cys that is associated with reduced survival. BRCA2-deficient PDAC cells exhibited increased DSBs and enhanced sensitivity to cyst(e)inase. The blocking of a second antioxidant pathway (thioredoxin/thioredoxin reductase) using auranofin or inhibiting DNA repair using the poly (ADP-ribose) polymerase (PARP) inhibitor, olaparib, led to significant increases in DSBs following cyst(e)inase treatment in all PDAC cells examined. Cyst(e)inase plus olaparib also synergistically inhibited growth of sensitive and resistant PDAC cells in both xenograft and allograft tumor models. Collectively, these results demonstrate an important role for oxidative DNA damage and ultimately DNA DSBs in the anticancer action of cyst(e)inase. The data further show the potential for combining agents that target alternate antioxidant pathways or by targeting DNA repair pathways or genetic liabilities in DNA repair pathways to enhance the therapeutic action of cyst(e)inase for PDAC.


Assuntos
Cisteína/metabolismo , Dano ao DNA , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/terapia , Animais , Auranofina/administração & dosagem , Dano ao DNA/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Camundongos , Estresse Oxidativo , Neoplasias Pancreáticas/etiologia , Espécies Reativas de Oxigênio , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Infect Dis (Lond) ; : 1-10, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963702

RESUMO

BACKGROUND: Klebsiella pneumoniae (KP) accounts for high antimicrobial resistance and mortality rates of bloodstream infections (BSIs). OBJECTIVES: To investigate incidence, antimicrobial resistance and risk factors for mortality of KP BSIs in East China. METHODS: A retrospective study of patients with KP BSIs was conducted in a tertiary care hospital from 2018 to 2022. Medical records of all hospitalised patients with KP BSIs were reviewed and analysed. The incidence, antimicrobial resistance and mortality of KP BSIs were evaluated. The Kaplan-Meier method was used to plot survival curves and logistic regression was used to analyse risk factors for crude 30-day mortality. RESULTS: A total of 379 inpatients with KP BSIs were enrolled. The incidence of patients with KP BSIs was fluctuating between 4.77 and 9.40 per 100,000 patient-days. The crude 30-day mortality rate of these patients was 26.39%. Of the 379 KPisolates, 197 (51.98%) were carbapenem-resistant (CR) and 252 (66.49%) were multidrug-resistant (MDR). All isolates showed the lowest resistance to tigecycline (13.77%) and polymyxin B (14.61%). Cases with MDR/CR isolates had significantly longer length of hospital stay, higher crude 30-day mortality and medical costs than non-MDR/non-CR isolates. Age, CR phenotype, paracentesis, indwelling central venous catheter (CVC), use of carbapenems, tetracyclines, polymyxins B, and irrational empiric treatment were independently associated with crude 30-day mortality. CONCLUSION: MDR/CR KP BSIs are associated with increased mortality, healthcare costs and prolonged hospitalisation. Patients with advanced age, CR phenotype, paracentesis, CVC, exposure to some antibiotics, and irrational empirical antibiotic treatment are at higher mortality risk.

5.
Cancers (Basel) ; 15(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38136273

RESUMO

Endometrial carcinoma (EC) is the most common gynecological malignancy in the United States. De novo pyrimidine synthesis pathways generate nucleotides that are required for DNA synthesis. Approximately 38% of human endometrial tumors present with an overexpression of human dihydroorotate dehydrogenase (DHODH). However, the role of DHODH in cancer cell DNA replication and its impact on modulating a treatment response is currently unknown. Here, we report that endometrial tumors with overexpression of DHODH are associated with a high mutation count and chromosomal instability. Furthermore, tumors with an overexpression of DHODH show significant co-occurrence with mutations in DNA replication polymerases, which result in a histologically high-grade endometrial tumor. An in vitro experiment demonstrated that the inhibition of DHODH in endometrial cancer cell lines significantly induced replication-associated DNA damage and hindered replication fork progression. Furthermore, endometrial cancer cells were sensitive to the DHODH inhibitor either alone or in combination with the Poly (ADP-ribose) polymerase 1 inhibitor. Our findings may have important clinical implications for utilizing DHODH as a potential target to enhance cytotoxicity in high-grade endometrial tumors.

6.
Front Public Health ; 11: 1294141, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38249405

RESUMO

Background: Pseudomonas aeruginosa (P. aeruginosa) accounts for high antimicrobial resistance and mortality rates of bloodstream infections (BSIs). We aim to investigate incidence, antimicrobial resistance and risk factors for mortality of P. aeruginosa BSIs among inpatients. Methods: A retrospective cohort study were conducted at two tertiary hospitals in 2017-2021. Medical and laboratory records of all inpatients diagnosed with P. aeruginosa BSIs were reviewed. A generalized linear mixed model was used to identify risk factors for mortality. Results: A total of 285 patients with P. aeruginosa BSIs were identified. Incidence of P. aeruginosa BSIs fluctuated between 2.37 and 3.51 per 100,000 patient-days over the study period. Out of 285 P. aeruginosa isolates, 97 (34.04%) were carbapenem-resistant (CR) and 75 (26.32%) were multidrug-resistant (MDR). These isolates showed low resistance to aminoglycosides (9.51-11.62%), broad-spectrum cephalosporins (17.19-17.61%), fluoroquinolones (17.25-19.43%), and polymyxin B (1.69%). The crude 30-day mortality rate was 17.89% (51/285). Healthcare costs of patients with MDR/CR isolates were significantly higher than those of patients with non-MDR/CR isolates (P < 0.001/=0.002). Inappropriate definitive therapy [adjusted odds ratio (aOR) 4.47, 95% confidence interval (95% CI) 1.35-14.77; P = 0.014], ICU stay (aOR 2.89, 95% CI: 1.26-6.63; P = 0.012) and corticosteroids use (aOR 2.89, 95% CI: 1.31-6.41; P = 0.009) were independently associated with 30-day mortality. Conclusion: Incidence of P. aeruginosa BSIs showed an upward trend during 2017-2020 but dropped in 2021. MDR/CR P. aeruginosa BSIs are associated with higher healthcare costs. Awareness is required that patients with inappropriate definitive antimicrobial therapy, ICU stay and corticosteroids use are at higher risk of death from P. aeruginosa BSIs.


Assuntos
Antibacterianos , Pseudomonas aeruginosa , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Estudos Retrospectivos , Incidência , Farmacorresistência Bacteriana , China/epidemiologia , Carbapenêmicos/farmacologia , Corticosteroides
7.
Pest Manag Sci ; 79(3): 1018-1029, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36326028

RESUMO

BACKGROUND: The invasive fall armyworm, Spodoptera frugiperda (J.E. Smith), has caused serious corn yield losses and increased the frequency of insecticide spraying on corn in Africa and Asia. Drawing lessons from the use of Bt corn to manage fall armyworm in the Americas, China released a certificate for the genetically modified corn event DBN3601T pyramidally expressing Cry1Ab and Vip3Aa19 for industrialization in 2021. Performance of the DBN3601T event against invasive fall armyworm in China was evaluated by plant tissue-based bioassays and field trials during 2019-2021. RESULTS: In the bioassays, tissues and organs of DBN3601T corn differed significantly in lethality to fall armyworm neonates in the order: leaf > husk > tassel and kernel > silk. In field trials, compared with non-Bt corn, DBN3601T corn greatly suppressed fall armyworm populations and damage; larval density, damage incidence, and leaf damage scores for DBN3601T corn were significantly lower than for non-Bt corn at different vegetative stages, and efficacy against larval populations during the 3 years ranged from 95.24% to 98.30%. CONCLUSION: A laboratory bioassay and 3-year field trials confirmed that DBN3601T corn greatly suppressed fall armyworm populations and has high potential as a control of this invasive pest, making it a key tactic for integrated management of fall armyworm in China. © 2022 Society of Chemical Industry.


Assuntos
Endotoxinas , Zea mays , Animais , Humanos , Recém-Nascido , Spodoptera/genética , Endotoxinas/genética , Zea mays/genética , Plantas Geneticamente Modificadas/genética , Proteínas de Bactérias/genética , Proteínas Hemolisinas/genética , Larva/genética , China , Resistência a Inseticidas
8.
J Exp Clin Cancer Res ; 42(1): 119, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37170264

RESUMO

BACKGROUND: Prostate Cancer (PCa) represents one of the most commonly diagnosed neoplasms in men and is associated with significant morbidity and mortality. Therapy resistance and significant side effects of current treatment strategies indicate the need for more effective agents to treat both androgen-dependent and androgen-independent PCa. In earlier studies, we demonstrated that depletion of L-cysteine/cystine with an engineered human enzyme, Cyst(e)inase, increased intracellular ROS levels and inhibited PCa growth in vitro and in vivo. The current study was conducted to further explore the mechanisms and potential combinatorial approaches with Cyst(e)inase for treatment of PCa. METHODS: DNA single strand breaks and clustered oxidative DNA damage were evaluated by alkaline comet assay and pulsed field gel electrophoresis, respectively. Neutral comet assay and immunofluorescence staining was used to measure DNA double strand breaks. Cell survival and reactive oxygen species level were measured by crystal violet assay and DCFDA staining, respectively. Western blot was used to determine protein expression. FACS analyses were preformed for immune cell phenotyping. Allograft and xenograft tumor models were used for assessing effects on tumor growth. RESULTS: PCa cells treated with Cyst(e)inase lead to DNA single and double strand breaks resulted from clustered oxidative DNA damage (SSBs and DSBs). Cyst(e)inase in combination with Auranofin, a thioredoxin reductase inhibitor, further increased intracellular ROS and DNA DSBs and synergistically inhibited PCa cell growth in vitro and in vivo. A combination of Cyst(e)inase with a PARP inhibitor (Olaparib) also increased DNA DSBs and synergistically inhibited PCa cell growth in vitro and in vivo without additional ROS induction. Knockdown of BRCA2 in PCa cells increased DSBs and enhanced sensitivity to Cyst(e)inase. Finally, Cyst(e)inase treatment altered tumor immune infiltrates and PD-L1 expression and sensitized PCa cells to anti-PD-L1 treatment. CONCLUSIONS: The current results demonstrate the importance of oxidative DNA damage either alone or in combination for Cyst(e)inase-induced anticancer activity. Furthermore, cysteine/cystine depletion alters the tumor immune landscape favoring enhanced immune checkpoint inhibition targeting PD-L1. Thus, combinatorial approaches with Cyst(e)inase could lead to novel therapeutic strategies for PCa.


Assuntos
Cistos , Neoplasias da Próstata , Masculino , Humanos , Cisteína/farmacologia , Cisteína/uso terapêutico , Inibidores de Checkpoint Imunológico/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Cistina/genética , Cistina/uso terapêutico , Androgênios , Linhagem Celular Tumoral , Dano ao DNA , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , DNA , Cistos/tratamento farmacológico
9.
Toxins (Basel) ; 14(8)2022 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-35893749

RESUMO

To control the fall armyworm (FAW), Spodoptera frugiperda (Smith), a serious threat to maize production in China, the Chinese government has issued biosafety certificates for transgenic insect-resistant maize expressing Bt (Bacillus thuringiensis) toxins including Bt-Cry1Ab maize (crop event DBN9936), Bt-Vip3Aa maize (event DBN9501), Bt-(Cry1Ab+Vip3Aa) maize with superimposed traits (event DBN9936 × DBN9501) and Bt-(Cry1Ab+Vip3Aa) maize with superimposed traits (event Bt11 × MIR162), but the susceptibility baselines of geographically distinct FAW populations to these events, which form the basis for managing resistance development in the pest to these events, are not clear. We used the diet-incorporated bioassays method to detect the susceptibilities of the seven FAW populations collected from Yunnan, Henan and Hubei provinces in China in 2021 to the insecticidal proteins of the four Bt maize events. The result showed that the susceptibilities of different geographical populations to Bt insecticidal proteins were significantly different. In the seven populations, the range in median lethal concentrations (LC50) of Cry1Ab expressed in DBN9936 was 0.87-2.63 µg/g, 0.14-0.30 µg/g for Vip3Aa expressed in DBN9501, 0.78-1.86 µg/g for Cry1Ab+Vip3Aa expressed in DBN9936 × DBN9501, and 0.36-1.42 µg/g for CryAb+Vip3Aa expressed in Bt11 × MIR162. The growth inhibition responses also showed that the susceptibilities varied with the different median growth inhibitory concentration (GIC50) ranges (0.38-1.22, 0.08-0.28, 0.28-0.87, and 0.24-0.78 µg/g, respectively). The variations in the ranges of the susceptibility baselines of the geographical populations of fall armyworm in China to the insecticidal proteins expressed in the four events provide a scientific basis for monitoring FAW population resistance to Bt maize and managing the populations using different Bt maize events.


Assuntos
Inseticidas , Zea mays , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/farmacologia , Proteínas de Bactérias/toxicidade , China , Endotoxinas/genética , Endotoxinas/metabolismo , Endotoxinas/farmacologia , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/farmacologia , Resistência a Inseticidas/genética , Inseticidas/metabolismo , Inseticidas/farmacologia , Larva/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Spodoptera/metabolismo , Zea mays/metabolismo
10.
Plants (Basel) ; 11(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36432854

RESUMO

Lepidopteran pests present a key problem for maize production in China. In order to develop a new strategy for the pest control, the Chinese government has issued safety certificates for insect-resistant transgenic maize, but whether these transformation events can achieve high dose levels to major target pests is still unclear. In this paper, the transformation events of DBN9936 (Bt-Cry1Ab), DBN9936 × DBN9501 (Bt-Cry1Ab + Vip3A), Ruifeng 125 (Bt-Cry1Ab/Cry2Aj), and MIR162 (Bt-Vip3A) were planted in the Huang-huai-hai summer corn region of China to evaluate the lethal effects on major lepidopteran pests, Spodoptera frugiperda, Helicoverpa armigera, Ostrinia furnacalis, Conogethes punctiferalis, Mythimna separata, Leucania loreyi, and Athetis lepigone, using an artificial diet containing lyophilized Bt maize tissue at a concentration representing a 25-fold dilution of tissue. The results showed that the corrected mortalities of DBN9936 (Bt-Cry1Ab), DBN9936 × DBN9501 (Bt-Cry1Ab + Vip3A), Ruifeng 125 (Bt-Cry1Ab/Cry2Aj), and MIR162 (Bt-Vip3A) to the seven pests were in the ranges 53.80~100%, 62.98~100%, 57.09~100%, and 41.02~100%, respectively. In summary, the events of DBN9936, DBN9936 × DBN9501, and MIR162 reached high dose levels to S. frugiperda. DBN9936 × DBN9501 only at the R1 stage reached a high dose level to H. armigera. DBN9936, DBN9936 × DBN9501, and Ruifeng 125, at most growth stages, reached high dose levels to O. furnacalis, and these three events at some stages also reached high dose levels to A. lepigone. Ruifeng 125 presented a high dose level only to C. punctiferalis. However, no transformations reached high dose levels to either M. separata or L. loreyi. This study provides a support for the breeding of high-dose varieties to different target pests, the combined application of multiple genes and the commercial regional planting of insect-resistant transgenic maize in China.

11.
Front Immunol ; 13: 1039009, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36624848

RESUMO

Base excision repair (BER) has evolved to maintain the genomic integrity of DNA following endogenous and exogenous agent induced DNA base damage. In contrast, aberrant BER induces genomic instability, promotes malignant transformation and can even trigger cancer development. Previously, we have shown that deoxyribo-5'-phosphate (dRP) lyase deficient DNA polymerase beta (POLB) causes replication associated genomic instability and sensitivity to both endogenous and exogenous DNA damaging agents. Specifically, it has been established that this loss of dRP lyase function promotes inflammation associated gastric cancer. However, the way that aberrant POLB impacts the immune signaling and inflammatory responses is still unknown. Here we show that a dRP lyase deficient variant of POLB (Leu22Pro, or L22P) increases mitotic dysfunction associated genomic instability, which eventually leads to a cytosolic DNA mediated inflammatory response. Furthermore, poly(ADP-ribose) polymerase 1 inhibition exacerbates chromosomal instability and enhances the cytosolic DNA mediated inflammatory response. Our results suggest that POLB plays a significant role in modulating inflammatory signaling, and they provide a mechanistic basis for future potential cancer immunotherapies.


Assuntos
DNA Polimerase beta , Humanos , DNA Polimerase beta/genética , DNA Polimerase beta/metabolismo , Reparo do DNA , DNA/genética , Replicação do DNA , Instabilidade Genômica
12.
Biomedicines ; 10(3)2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35327359

RESUMO

Innate immunity is critical for immediate recognition and elimination of invading pathogens or defense against cancer cell growth. Dysregulation of innate immune systems is associated with the pathogenesis of different types of inflammatory diseases, including cancer. In addition, the maintenance of innate immune cells' genomic integrity is crucial for the survival of all organisms. Oxidative stress generated from innate immune cells may cause self-inflicted DNA base lesions as well as DNA damage on others neighboring cells, including cancer cells. Oxidative DNA base damage is predominantly repaired by base excision repair (BER). BER process different types of DNA base lesions that are presented in cancer and innate immune cells to maintain genomic integrity. However, mutations in BER genes lead to impaired DNA repair function and cause insufficient genomic integrity. Moreover, several studies have implicated that accumulation of DNA damage leads to chromosomal instability that likely activates the innate immune signaling. Furthermore, dysregulation of BER factors in cancer cells modulate the infiltration of innate immune cells to the tumor microenvironment. In the current review, the role of BER in cancer and innate immune cells and its impact on innate immune signaling within the tumor microenvironment is summarized. This is a special issue that focuses on DNA damage and cancer therapy to demonstrate how BER inhibitor or aberrant repair modulates innate inflammatory response and impact immunotherapy approaches. Overall, the review provides substantial evidence to understand the impact of BER in innate immune response dynamics within the current immune-based therapeutic strategy.

13.
Pest Manag Sci ; 78(11): 4975-4982, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36054519

RESUMO

BACKGROUND: The fall armyworm (FAW) Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) invaded Myanmar and China in 2018 and greatly impacted agricultural production and ecosystem balance in these areas. FAW is a migratory insect, but its seasonal migration pattern between the two countries has been largely unknown. From 2019 to 2021, we monitored the seasonal migration of FAW in the China-Myanmar border area using a searchlight trap, assessed the reproductive development status of female migrants and traced the migratory routes by trajectory simulation. RESULTS: FAW moths were trapped by the searchlight trap in Lancang County (Yunnan, China) all year, with obvious seasonal differences in the number caught. There were small-scale persistent trapping peaks in spring and summer, and obvious peaks in autumn; only a small number of moths were trapped in winter. Examination of the ovaries of female moths collected in different seasons showed that most females had matured, indicating that the moths were migrating and did not take off from the local area. In the migration trajectory simulation, FAW mainly migrated from Myanmar to Southwest China in spring and summer and back to Myanmar in autumn. CONCLUSION: Our findings indicate that FAW migrates between China and Myanmar according to the monsoon circulation, which will help guide cross-border regional monitoring and management strategies against this pest. © 2022 Society of Chemical Industry.


Assuntos
Ecossistema , Animais , China , Feminino , Mianmar , Estações do Ano , Spodoptera
14.
Int Rev Cell Mol Biol ; 364: 163-193, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34507783

RESUMO

Oxidative and alkylating DNA damage occurs under normal physiological conditions and exogenous exposure to DNA damaging agents. To counteract DNA base damage, cells have evolved several defense mechanisms that act at different levels to prevent or repair DNA base damage. Cells combat genomic lesions like these including base modifications, abasic sites, as well as single-strand breaks, via the base excision repair (BER) pathway. In general, the core BER process involves well-coordinated five-step reactions to correct DNA base damage. In this review, we will uncover the current understanding of BER mechanisms to maintain genomic stability and the biological consequences of its failure due to repair gene mutations. The malfunction of BER can often lead to BER intermediate accumulation, which is genotoxic and can lead to different types of human disease. Finally, we will address the use of BER intermediates for targeted cancer therapy.


Assuntos
Reparo do DNA , Saúde , Animais , Dano ao DNA/genética , Reparo do DNA/genética , Regulação da Expressão Gênica , Humanos , Inflamação/genética , Inflamação/patologia , Oxirredução
15.
Front Genet ; 12: 635808, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33897761

RESUMO

Alpha-ketoglutarate-dependent dioxygenase (ALKBH) is a DNA repair gene involved in the repair of alkylating DNA damage. There are nine types of ALKBH (ALKBH1-8 and FTO) identified in humans. In particular, certain types of ALKBH enzymes are dioxygenases that directly reverse DNA methylation damage via transfer of a methyl group from the DNA adduct onto α-ketoglutarate and release of metabolic products including succinate and formaldehyde. Here, we tested whether ALKBH6 plays a significant role in preventing alkylating DNA damage and decreasing genomic instability in pancreatic cancer cells. Using an E. coli strain deficient with ALKB, we found that ALKBH6 complements ALKB deficiency and increases resistance after alkylating agent treatment. In particular, the loss of ALKBH6 in human pancreatic cancer cells increases alkylating agent-induced DNA damage and significantly decreases cell survival. Furthermore, in silico analysis from The Cancer Genome Atlas (TCGA) database suggests that overexpression of ALKBH6 provides better survival outcomes in patients with pancreatic cancer. Overall, our data suggest that ALKBH6 is required to maintain the integrity of the genome and promote cell survival of pancreatic cancer cells.

16.
J Econ Entomol ; 114(3): 1145-1158, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33769527

RESUMO

Ambient humidity can directly affect the water balance in insects. The migratory fall armyworm, Spodoptera frugiperda Smith, has spread to more than 60 countries and regions in Africa, Asia, and Oceania that have a great difference in average ambient humidity. Understanding the effects of ambient humidity changes on its development, survival, and reproduction can help to predict its population dynamics in different habitats. Therefore, we evaluated the effects of atmospheric relative humidity (RH) on the development, survival, and reproduction and soil moisture on the pupation and emergence of fall armyworm. As a result, survival and pupal mass increased significantly with increasing RH. Among the five RHs tested, 80% RH was the most suitable for fall armyworm with the highest intrinsic rate of increase (r), finite rate of increase (λ), and net reproduction rate (R0). The population growth at the different RHs in decreasing order was 80 > 100 > 60 > 40 > 20%. A relative moisture (RM) of soil from 6.80 to 47.59% was suitable for fall armyworm pupation, survival, and eclosion, but fall armyworm could not pupate normally in soil with 88.39 and 95.19% RM. The survival and emergence rate of fall armyworm pupae were reduced by irrigation that increased the RM after the mature larvae entered the soil. These findings may be helpful for refining laboratory rearing protocols, population forecasting, and management of fall armyworm.


Assuntos
Reprodução , Zea mays , África , Animais , Ásia , China , Umidade , Larva , Spodoptera
17.
Infect Control Hosp Epidemiol ; 42(8): 968-977, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33349283

RESUMO

OBJECTIVE: To determine risk factors for carbapenemase-producing organisms (CPOs) and to determine the prognostic impact of CPOs. DESIGN: A retrospective matched case-control study. PATIENTS: Inpatients across Scotland in 2010-2016 were included. Patients with a CPO were matched with 2 control groups by hospital, admission date, specimen type, and bacteria. One group comprised patients either infected or colonized with a non-CPO and the other group were general inpatients. METHODS: Conditional logistic regression models were used to identify risk factors for CPO infection and colonization, respectively. Mortality rates and length of postisolation hospitalization were compared between CPO and non-CPO patients. RESULTS: In total, 70 CPO infection cases (with 210 general inpatient controls and 121 non-CPO controls) and 34 CPO colonization cases (with 102 general inpatient controls and 60 non-CPO controls) were identified. Risk factors for CPO infection versus general inpatients were prior hospital stay (adjusted odds ratio [aOR], 4.05; 95% confidence interval [CI], 1.52-10.78; P = .005), longer hospitalization (aOR, 1.07; 95% CI, 1.04-1.10; P < .001), longer intensive care unit (ICU) stay (aOR, 1.41; 95% CI, 1.01-1.98; P = .045), and immunodeficiency (aOR, 3.68; 95% CI, 1.16-11.66; P = .027). Risk factors for CPO colonization were prior high-dependency unit (HDU) stay (aOR, 11.46; 95% CI, 1.27-103.09; P = .030) and endocrine, nutritional, and metabolic (ENM) diseases (aOR, 3.41; 95% CI, 1.02-11.33; P = .046). Risk factors for CPO infection versus non-CPO infection were prolonged hospitalization (aOR, 1.02; 95% CI, 1.00-1.03; P = .038) and HDU stay (aOR, 1.13; 95% CI, 1.02-1.26; P = .024). No differences in mortality rates were detected between CPO and non-CPO patients. CPO infection was associated with longer hospital stay than non-CPO infection (P = .041). CONCLUSIONS: A history of (prolonged) hospitalization, prolonged ICU or HDU stay; ENM diseases; and being immunocompromised increased risk for CPO. CPO infection was not associated with increased mortality but was associated with prolonged hospital stay.


Assuntos
Pacientes Internados , Proteínas de Bactérias , Estudos de Casos e Controles , Humanos , Estudos Retrospectivos , Fatores de Risco , beta-Lactamases
18.
J Insect Physiol ; 132: 104248, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33945808

RESUMO

Since 2016, the fall armyworm (FAW, Spodoptera frugiperda) has invaded large parts of Africa and Asia, impacting millions of hectares of maize crops and thereby posing a major threat to food security. The rapid geographic spread and outbreak dynamics of S. frugiperda are tied to its unique dispersal ability and long-distance migration capability. Yet, up till present, limited research has been conducted on the physiological determinants of S. frugiperda flight and migration. In this study, we used laboratory experiments to assess whether mating and oviposition affect S. frugiperda flight ability and wingbeat frequency. During 2019-2020, migratory FAW females were trapped in Yunnan (China) and dissected to assess ovarian development. Tethered flight assays showed that gravid S. frugiperda females exhibited strong flight ability at 1-3 days following the onset of oviposition. Flight distance and duration negatively correlated with the number of deposited eggs. Ovarian dissections further showed that over 50% of migrant females were mated and 46-54% had initiated oviposition. Our study shows the complex, yet nuanced effects of reproductive status on flight capacity, with possibly a facultative trade-off between flight and reproduction. These novel insights into S. frugiperda physiology and migration behavior can guide future monitoring and integrated pest management (IPM) programs against this newly-invasive pest in China and abroad.


Assuntos
Voo Animal/fisiologia , Reprodução/fisiologia , Spodoptera/fisiologia , Distribuição Animal/fisiologia , Animais , Feminino , Oviposição , Controle de Pragas
19.
Talanta ; 235: 122791, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34517649

RESUMO

A new type of temperature-sensitive imprinted composite membranes(ICMs) was developed. Poly N,N-diethylacrylamide (DEA) blocks, as temperature-sensitive polymer, were grafted onto the substrate of the imprinted polymer separation layer to endow membranes with better adsorption effect. The comprehensive properties of the imprinted composite membranes were adequately tested and evaluated in detail. Results showed that ReO4- -ICMs (Re-ICMs) with temperature-sensitive recognition sites could adjust the structure of the imprinted holes at different temperatures, which presented excellent performance in the selective separation and purification of ReO4-. The prepared Re-ICMs exhibit the maximum adsorption capacity of 0.1639 mmol/g at 35 °C with the equilibrium adsorption time of 2 h. After ten adsorption/desorption cycles, Re-ICMs could still maintain 73.5% of the original adsorption capacity, the separation degree of ReO4-/MnO4- was only reduced from the initial 24.5 to 15.9, and the desorption ratio dropped from 80.4% to 68.4%, indicating that Re-ICMs have excellent adsorption and separation performance and reusability.


Assuntos
Impressão Molecular , Adsorção , Biomimética , Polímeros , Temperatura
20.
Philos Trans R Soc Lond B Biol Sci ; 376(1829): 20200275, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34053266

RESUMO

This study demonstrates that an adoption of a segmenting and shielding strategy could increase the scope to partially exit COVID-19 lockdown while limiting the risk of an overwhelming second wave of infection. We illustrate this using a mathematical model that segments the vulnerable population and their closest contacts, the 'shielders'. Effects of extending the duration of lockdown and faster or slower transition to post-lockdown conditions and, most importantly, the trade-off between increased protection of the vulnerable segment and fewer restrictions on the general population are explored. Our study shows that the most important determinants of outcome are: (i) post-lockdown transmission rates within the general and between the general and vulnerable segments; (ii) fractions of the population in the vulnerable and shielder segments; (iii) adherence to protective measures; and (iv) build-up of population immunity. Additionally, we found that effective measures in the shielder segment, e.g. intensive routine screening, allow further relaxations in the general population. We find that the outcome of any future policy is strongly influenced by the contact matrix between segments and the relationships between physical distancing measures and transmission rates. This strategy has potential applications for any infectious disease for which there are defined proportions of the population who cannot be treated or who are at risk of severe outcomes. This article is part of the theme issue 'Modelling that shaped the early COVID-19 pandemic response in the UK'.


Assuntos
COVID-19/epidemiologia , Pandemias , COVID-19/transmissão , COVID-19/virologia , Controle de Doenças Transmissíveis/tendências , Humanos , Modelos Teóricos , SARS-CoV-2/patogenicidade , Reino Unido/epidemiologia
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