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1.
J Agric Food Chem ; 72(4): 2263-2276, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38235648

RESUMO

Crystal (Cry) toxins, produced by Bacillus thuringiensis, are widely used as effective biological pesticides in agricultural production. However, insects always quickly evolve adaptations against Cry toxins within a few generations. In this study, we focused on the Cry1Ac protoxin activated by protease. Our results identified PxTrypsin-9 as a trypsin gene that plays a key role in Cry1Ac virulence in Plutella xylostella larvae. In addition, P. xylostella miR-2b-3p, a member of the micoRNA-2 (miR-2) family, was significantly upregulated by Cry1Ac protoxin and targeted to PxTrypsin-9 downregulated its expression. The mRNA level of PxTrypsin-9, regulated by miR-2b-3p, revealed an increased tolerance of P. xylostella larvae to Cry1Ac at the post-transcriptional level. Considering that miR-2b and trypsin genes are widely distributed in various pest species, our study provides the basis for further investigation of the roles of miRNAs in the regulation of the resistance to Cry1Ac and other insecticides.


Assuntos
Bacillus thuringiensis , Inseticidas , MicroRNAs , Mariposas , Animais , Mariposas/genética , Mariposas/metabolismo , Larva/genética , Larva/metabolismo , Tripsina/genética , Tripsina/metabolismo , Inseticidas/farmacologia , Inseticidas/metabolismo , Bacillus thuringiensis/química , Endotoxinas/genética , Endotoxinas/farmacologia , Endotoxinas/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacologia , Proteínas Hemolisinas/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Resistência a Inseticidas/genética
2.
Environ Pollut ; 271: 116271, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33401210

RESUMO

Insect gut microbiotas have a variety of physiological functions for host growth, development, and immunity. Bacillus thuringiensis (Bt) is known to kill insect pests by releasing insecticidal protoxins, which are activated in the insect midgut. However, the interplay among Bt infection, host immunity, and gut microbiota are still unclear. Here we show that Bt Cry1Ac protoxin interacts with the gut microbiota to accelerate the mortality of P. xylostella larvae. Cry1Ac protoxin was found to cause a dynamic change in the midgut and hemocoel microbiota of P. xylostella, with a significant increase in bacterial load and a significant reduction in bacterial diversity. In turn, loss of gut microbiota significantly decreased the Bt susceptibility of P. xylostella larvae. The introduction of three gut bacterial isolates Enterococcus mundtii (PxG1), Carnobacterium maltaromaticum (PxCG2), and Acinetobacter guillouiae (PxCG3) restored sensitivity to Bt Cry1Ac protoxin. We also found that Cry1Ac protoxin and native gut microbiota can trigger host midgut immune response, which involves the up-regulation of expression of Toll and IMD pathway genes and most antimicrobial peptide genes, respectively. Our findings further shed light on the interplay between insect gut microbiota and host immunity under the Bt toxin killing pressure, and this may provide insights for improving the management of Bt resistance and lead to new strategies for biological control of insect pests.


Assuntos
Bacillus thuringiensis , Microbioma Gastrointestinal , Mariposas , Acinetobacter , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Carnobacterium , Endotoxinas/toxicidade , Enterococcus , Proteínas Hemolisinas , Imunidade , Proteínas de Insetos , Resistência a Inseticidas , Larva
3.
J Ind Microbiol Biotechnol ; 37(6): 581-5, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20204452

RESUMO

Jerusalem artichoke (JA) is a perennial herbaceous plant widely available as non-grain raw material. Microbial lipid has been suggested as a potential feedstock for large scale biodiesel production. This paper describes lipid production using JA tuber processed by oleaginous yeast Rhodosporidium toruloides Y4. Batch and fed-batch modes were tested with feeding of concentrated JA extracts or JA hydrolysates. Cultivation of R. toruloides Y4 with JA extracts gave a moderate cellular lipid content of 40% (w/w), whereas lipid titer and cellular lipid content reached 39.6 g l(-1) and 56.5% (w/w), respectively, when JA hydrolysates were fed. Our results suggested that JA tubers may be further explored as raw material for large scale microbial lipid production.


Assuntos
Basidiomycota/metabolismo , Helianthus/metabolismo , Lipídeos/biossíntese , Biocombustíveis , Reatores Biológicos , Fermentação
4.
Pest Manag Sci ; 76(6): 2113-2126, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31951096

RESUMO

BACKGROUND: Parasitoid venom is composed of a complex mixture of various active substances with different biological functions and is injected in the host during the parasitoid oviposition. Anastatus japonicus (Hymenoptera: Eupelmidae) is an egg parasite of Tessaratoma papillosa (Hemiptera: Tessaratomidae). Although the venom of this egg parasitoid plays an important role in the parasitic process, relatively little work has been done to address the mechanism. RESULTS: In the present study, proteomic analysis was performed to identify the proteins that play an important role in the parasitic process of A. japonicus. A total of 2084 proteins were identified, including 81 putative venom proteins, most of which were identified as Hexamerin, Chitinase 2, Calreticulin, Heat shock protein 83-like, Serine protease, Arginine kinase, Phosphoserine aminotransferase and Actin protein. Together the before (Be) and after (Af) parasitization venom contains 1628 proteins, including 212 DEPs with 181 and 31 significantly up-regulated and down-regulated respectively. In addition, 10 differentially expressed proteins (DEPs) with fold change ≥8.71 were subjected to RT-qPCR to validate the proteomic data. The differential expression analysis revealed that nine proteins were specifically present in the pre-parasitic venom, whereas 26 proteins were specific to the post-parasitic treatments. Results of RT-qPCR analysis showed high expression of the selected DEPs which further validated our proteomics data. CONCLUSION: These new proteomic data greatly enrich our current knowledge about key venom proteins associated with parasitic process in A. japonicus and contribute to better understanding of the parasitic mechanisms leading to the development of new biological control strategies. © 2020 Society of Chemical Industry.


Assuntos
Hemípteros , Himenópteros , Animais , Feminino , Interações Hospedeiro-Parasita , Oviposição , Proteômica , Transcriptoma
5.
Brachytherapy ; 18(3): 420-425, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30745017

RESUMO

PURPOSE: The effect of 125I seed implantation for the treatment of local residual tumor of hepatocellular carcinoma located beneath the diaphragm (HCC-LBD) after transcatheter arterial chemoembolization (TACE) has not yet been reported. This retrospective study was performed to evaluate the safety and efficacy of 125I seeds implantation (ISI) for the treatment of residual HCC-LBD after TACE. METHODS AND MATERIALS: A total of 18 patients treated with ISI between August 2012 and March 2018 for residual HCC-LBD after single or multiple TACE were enrolled. Local control, survival, and postoperative complications were analyzed retrospectively. Overall followup time was displayed by survival curves. RESULTS: The 18 patients received a total of 20 ISI treatments. The total number of seeds implanted was 650, with a mean of 36 ± 13 seeds per patients (range, 20-70). Mean D90 was 123 Gy. Complete response + partial response (CR + PR) was documented in 14, 16, and 16 of patients at 3, 6, and 12 months after implantation, respectively. In four patients, seeds implantation was performed through the diaphragm; two of these patients developed small pneumothoraces. Pulmonary compression of pneumothorax is less than 30% combined with a little blood in sputum, no chest tightness, shortness of breath, all symptoms subsided without interventions, and the patients were discharged after observation for 2 days. After the procedure, routine blood examination and liver and kidney function were normal. CONCLUSION: The combination of TACE with ISI appears to be a safe and efficient treatment for residual HCC-BLD. IMPLICATIONS FOR PRACTICE: This study evaluated the feasibility, safety, and short-term efficacy of ISI for local residual tumor of hepatocellular carcinoma located beneath the diaphragm (HCC-LBD) after TACE. Results suggest that residual tumor of HCC after TACE located in the posterosuperior part of the liver (segments seven and eight), laparoscopic liver resection, and alblation is difficult to perform and that as a supplement treatment, 125I seeds implantation is safe and easy accessible. TACE combined with 125I seeds has excellent local control effectiveness, and long-term efficacy and survival benefit still need to be more comprehensively evaluated.


Assuntos
Braquiterapia , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Adulto , Idoso , Antineoplásicos/administração & dosagem , Braquiterapia/efeitos adversos , Quimioembolização Terapêutica , Terapia Combinada , Diafragma , Feminino , Humanos , Radioisótopos do Iodo , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Pneumotórax/etiologia , Estudos Retrospectivos , Resultado do Tratamento
6.
J Contemp Brachytherapy ; 11(1): 35-40, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30911308

RESUMO

PURPOSE: The aim of the study was to determine how many times iodine-125 (125I) seed brachytherapy (ISB) for recurrent pulmonary metastases (RPM) can be done, and the clinical efficacy and complications of repeated ISB in RPM treatment. MATERIAL AND METHODS: Between September 2013 and August 2018, 18 patients with RPM, after conventional chemotherapy, radiotherapy, and trans-arterial chemoembolization, received CT-guided repeated ISB. Patients were followed up, and local control, survival, and post-operative complications were analyzed retrospectively. The Kaplan-Meier method was used for survival analyses. RESULTS: Eighty-two metastases in 18 patients were treated with ISB, with 71 implantations (mean number of implantations per patient, 4; range, 3-8). The total number of implanted 125I seeds was 1,220 (mean number per patient, 68; minimum, 40; maximum, 110). The mean value of D90 for ISB was 138 Gy. Local control was 91.46%, 90.24%, and 89.02% at 1, 3, and 6 months after ISB, respectively. After repeated ISB, good local control was achieved, and all patients were discharged from hospital within 3 days. One month after, six metastases of large diameter were treated with ISB; computed tomography revealed level 1 radioactive injury to the lungs, but special treatment was not administered. Post-operative renal, hepatic, and vascular functions were normal. CONCLUSIONS: ISB for RPM is safe and efficacious. RPM treatment seems not to be limited by number of times ISB could be repeated; at least up to 8 times for different sites of lung.

7.
J Contemp Brachytherapy ; 10(4): 360-367, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30237819

RESUMO

PURPOSE: To evaluate the efficacies of 125I seed implantation and stereotactic body radiation therapy (SBRT) in treatment of recurrent lung metastases from colorectal cancer, to compare the tolerance of lung tissue to both forms of radiotherapy, and to analyze the factors that affect the prognosis. MATERIAL AND METHODS: According to treatment received, thirty colorectal cancer patients with post-operative lung metastases were separated into two groups: 125I seed implantation group (group A; n = 16) and SBRT group (group B; n = 14). Patients were followed up, and local control rate, survival, and post-operative complications were analyzed retrospectively. Kaplan-Meier method was used for survival analysis. Cox proportional hazards model was used to identify the independent predictors of poor prognosis. RESULTS: Survival was significantly different between group A and group B (median survival, 15 months and 11.5 months, respectively; p = 0.015). Local control rates at the first, third, sixth, and twelfth months after treatment were all > 80%, with no significant difference between the two groups (p = 0.829). Significant differences were seen between the two groups in the number of treatments received (p = 0.009) and the incidence of radiation pneumonitis (p < 0.001) as well as radiation-induced pulmonary fibrosis (p = 0.005). On multivariate regression analysis radiation pneumonitis was an independent predictor of poor prognosis (HR = 3.356, 95% CI: 1.518-7.421; p = 0.003). CONCLUSIONS: 125I seeds brachytherapy and SBRT are both effective for control of lung metastases but the former causes milder lung tissue damage. It can be repeated after short intervals, and appears to be a safe and efficient treatment for lung metastases.

8.
J Contemp Brachytherapy ; 9(2): 132-138, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28533801

RESUMO

PURPOSE: To retrospectively evaluate the efficacy and safety of computed tomography (CT)-guided percutaneous interstitial brachytherapy using 125I radioactive seeds for multiple pulmonary metastatic tumors. MATERIAL AND METHODS: Between September 2013 and December 2015, 22 patients with multiple pulmonary metastases, who after conventional chemotherapy and trans-arterial chemoembolization (TACE) therapy were considered unable to withstand stereotactic body radiation therapy (SBRT), received CT-guided 125I brachytherapy. Clinical data were studied retrospectively. A planning target volume of 90% (D90) was 120-160 Gy for 125I seeds with an activity of 25.9 MBq. A CT-based evaluation performed 1, 2, and 6 months' post-implantation enabled review of local control of tumors. RESULTS: Twenty-two patients with 65 pulmonary metastases successfully completed treatment. The mean value for D90 for implantation for 125I seeds was 132 Gy. Complete response (CR) + partial response (PR) was documented in 81.54%, 78.46%, and 78.46% of patients at 1, 2, and 6 months after implantation, respectively. Fourteen out of 22 patients had CR, 3 had PR, 2 had stable disease (SD), and 3 had progressive disease (PD). Most of the metastases (CR + PR + SD; 87.69% after 6 months) were controlled by implantation. CONCLUSIONS: CT-guided 125I brachytherapy is a safe and effective treatment for multiple pulmonary metastatic tumors, and can achieve good short-term local control, so long as the radiation dose is sufficient.

9.
Brachytherapy ; 15(2): 224-30, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26832671

RESUMO

PURPOSE: To retrospectively evaluate the efficacy and safety of CT-guided implantation of (125)I seeds (permanent brachytherapy) for metastatic tumors of the hepatic portal system (HPS). METHODS AND MATERIALS: Between January 2012 and January 2015, 13 patients with metastases measuring >3.0 cm in short-axis diameter, which remained in the HPS after conventional chemotherapy and/or transcatheter arterial chemoembolization, and for which an effective therapeutic dose from external beam radiotherapy could not be delivered, received CT-guided (125)I brachytherapy. Clinical data were studied retrospectively. In terms of metrological requirements, the minimum dose to 90% of the target volume (D90) was 90-160 Gy for (125)I seeds with activity of 2.96 × 10(7)Bq. CT-based evaluation after 2, 4, and 8 weeks, as well as 6 months after implantation enabled review of local control of tumors. RESULTS: All symptoms were improved after (125)I brachytherapy. The mean value for D90 for implantation of (125)I seeds was 136 Gy. Complete response (CR) + partial response (PR) was documented in 61.5%, 69.2%, and 84.6% of patients at 2 weeks, 4 weeks, and 6 months after implantation, respectively. Four of 13 patients had complete response, 7 cases had PR, 1 patient had stable disease, and 1 case had progressive disease. All metastatic foci were controlled by implantation. No serious complications were observed. CONCLUSION: CT-guided (125)I brachytherapy is a safe and effective treatment for metastatic tumors of the HPS and can achieve good local control in the short term as long as the radiation dose is sufficient. CT-guided (125)I brachytherapy carries few complications, is simple, safe, and a good complement to cancer treatment.


Assuntos
Braquiterapia , Radioisótopos do Iodo/uso terapêutico , Sistema Porta , Radioterapia Guiada por Imagem , Neoplasias Vasculares/radioterapia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Intervencionista/métodos , Dosagem Radioterapêutica , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Neoplasias Vasculares/diagnóstico por imagem , Neoplasias Vasculares/secundário
10.
PLoS One ; 10(2): e0117741, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25647607

RESUMO

The aim of this study was to assess the effect of 48-week entecavir therapy on serum and intrahepatic hepatitis B virus, covalently closed circular DNA (HBV cccDNA) levels in hepatitis B e antigen (HBeAg)-positive patients. A total of 120 patients with HBeAg-positive chronic hepatitis were treated with entecavir for 48 weeks. Serum HBV markers, total HBV DNA, and HBV cccDNA levels were measured at baseline and week 48. Biopsies from 20 patients were available for both intrahepatic total HBV DNA and cccDNA testing at these timepoints. HBV cccDNA levels were decreased from a median level of 5.1×106 copies/mL at baseline to a median level of 2.4×103 copies/mL at week 48. Reduction magnitudes of HBV cccDNA in patients with normalized alanine aminotransferase levels and those undergoing HBeAg seroconversion were significantly greater than those in alanine aminotransferase-abnormal and HBeAg positive patients. Intrahepatic HBV cccDNA was decreased significantly after 48 weeks of treatment, but could not be eradicated. In conclusion, treatment of HBeAg-positive hepatitis B patients with entecavir for 48 weeks decreased serum and intrahepatic HBV cccDNA significantly, and the magnitude of HBV cccDNA reduction was related to total HBV DNA decrease, alanine aminotransferase normalization, and HBeAg seroconversion.


Assuntos
Antivirais/uso terapêutico , DNA Viral/análise , Guanina/análogos & derivados , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Hepatite B/tratamento farmacológico , Fígado/virologia , Adolescente , Adulto , DNA Circular/análise , DNA Circular/sangue , DNA Circular/genética , DNA Viral/sangue , DNA Viral/genética , Feminino , Guanina/uso terapêutico , Hepatite B/sangue , Antígenos E da Hepatite B/análise , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/genética , Hepatite B Crônica/sangue , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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