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1.
Toxins (Basel) ; 13(9)2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34564662

RESUMEN

Transgenic crops expressing Bacillus thuringiensis (Bt) insecticidal proteins have been extensively planted for insect pest control, but the evolution of Bt resistance in target pests threatens the sustainability of this approach. Mutations of cadherin in the midgut brush border membrane was associated with Cry1Ac resistance in several lepidoptera species, including the Asian corn borer, Ostrinia furnacalis, a major pest of maize in Asian-Western Pacific countries. However, the causality of O. furnacalis cadherin (OfCad) with Cry1Ac resistance remains to be clarified. In this study, in vitro and in vivo approaches were employed to examine the involvement of OfCad in mediating Cry1Ac toxicity. Sf9 cells transfected with OfCad showed significant immunofluorescent binding with Cry1Ac toxin and exhibited a concentration-dependent mortality effect when exposed to Cry1Ac. The OfCad knockout strain OfCad-KO, bearing homozygous 15.4 kb deletion of the OfCad gene generated by CRISPR/Cas9 mutagenesis, exhibited moderate-level resistance to Cry1Ac (14-fold) and low-level resistance to Cry1Aa (4.6-fold), but no significant changes in susceptibility to Cry1Ab and Cry1Fa, compared with the original NJ-S strain. The Cry1Ac resistance phenotype was inherited as autosomal, recessive mode, and significantly linked with the OfCad knockout in the OfCad-KO strain. These results demonstrate that the OfCad protein is a functional receptor for Cry1Ac, and disruption of OfCad confers a moderate Cry1Ac resistance in O. furnacalis. This study provides new insights into the mode of action of the Cry1Ac toxin and useful information for designing resistance monitoring and management strategies for O. furnacalis.


Asunto(s)
Toxinas de Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis/toxicidad , Cadherinas/metabolismo , Resistencia a la Enfermedad/efectos de los fármacos , Insectos/metabolismo , Resistencia a los Insecticidas/efectos de los fármacos , Zea mays/metabolismo , Zea mays/parasitología , Animales , Bacillus thuringiensis/química
2.
Toxins (Basel) ; 12(4)2020 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-32290427

RESUMEN

The adoption of transgenic crops expressing Bacillus thuringiensis (Bt) insecticidal crystalline (Cry) proteins has reduced insecticide application, increased yields, and contributed to food safety worldwide. However, the efficacy of transgenic Bt crops is put at risk by the adaptive resistance evolution of target pests. Previous studies indicate that resistance to Bacillus thuringiensis Cry1A and Cry1F toxins was genetically linked with mutations of ATP-binding cassette (ABC) transporter subfamily C gene ABCC2 in at least seven lepidopteran insects. Several strains selected in the laboratory of the Asian corn borer, Ostrinia furnacalis, a destructive pest of corn in Asian Western Pacific countries, developed high levels of resistance to Cry1A and Cry1F toxins. The causality between the O. furnacalisABCC2 (OfABCC2) gene and resistance to Cry1A and Cry1F toxins remains unknown. Here, we successfully generated a homozygous strain (OfC2-KO) of O. furnacalis with an 8-bp deletion mutation of ABCC2 by the CRISPR/Cas9 approach. The 8-bp deletion mutation results in a frame shift in the open reading frame of transcripts, which produced a predicted protein truncated in the TM4-TM5 loop region. The knockout strain OfC2-KO showed much more than a 300-fold resistance to Cry1Fa, and low levels of resistance to Cry1Ab and Cry1Ac (<10-fold), but no significant effects on the toxicities of Cry1Aa and two chemical insecticides (abamectin and chlorantraniliprole), compared to the background NJ-S strain. Furthermore, we found that the Cry1Fa resistance was autosomal, recessive, and significantly linked with the 8-bp deletion mutation of OfABCC2 in the OfC2-KO strain. In conclusion, in vivo functional investigation demonstrates the causality of the OfABCC2 truncating mutation with high-level resistance to the Cry1Fa toxin in O. furnacalis. Our results suggest that the OfABCC2 protein might be a functional receptor for Cry1Fa and reinforces the association of this gene to the mode of action of the Cry1Fa toxin.


Asunto(s)
Toxinas de Bacillus thuringiensis/metabolismo , Bacillus thuringiensis/metabolismo , Endotoxinas/metabolismo , Proteínas Hemolisinas/metabolismo , Proteínas de Insectos/genética , Mariposas Nocturnas/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Control Biológico de Vectores , Plantas Modificadas Genéticamente/parasitología , Zea mays/parasitología , Animales , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis/genética , Sistemas CRISPR-Cas , Endotoxinas/genética , Regulación Bacteriana de la Expresión Génica , Técnicas de Inactivación de Genes , Proteínas Hemolisinas/genética , Proteínas de Insectos/deficiencia , Resistencia a los Insecticidas/genética , Mariposas Nocturnas/metabolismo , Proteína 2 Asociada a Resistencia a Múltiples Medicamentos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/deficiencia , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Zea mays/genética , Zea mays/metabolismo
3.
Shanghai Kou Qiang Yi Xue ; 26(3): 251-253, 2017 Jun.
Artículo en Chino | MEDLINE | ID: mdl-29098239

RESUMEN

PURPOSE: To study the correlation between apical foramen area and accuracy of PropexII electronic apex locator under destroyed apical constriction. METHODS: Forty extracted teeth with single straight root canal were ground down 1 mm in the root tip and placed in 2% liquid agar gel injected into Castro model. The length of root canal was measured by PropexII electronic apex locator. The difference (L) between the electronic length (LP) and actual length was calculated. Imaging of apical foramen was recorded under microscope and apical foramen area (S) was measured by image processing software Photoshop CS. SPSS 22.0 software package was used to analyze the linear correlation and regression. RESULTS: With ±0.5 mm as the allowable range, all value of L was positive. The precise rate of PropexII was 52.5% when apical constriction was destroyed. There was a linear relationship between S and L (S=0.04+0.11×L,R=0.903). CONCLUSIONS: The accuracy decreases when apical constriction is destroyed. The accuracy is worse when the apical foramen area is larger.


Asunto(s)
Cerámica , Odontometría , Preparación del Conducto Radicular , Aleaciones , Cavidad Pulpar , Ápice del Diente
4.
Springerplus ; 5(1): 1785, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27795927

RESUMEN

Improving the performance of clinical departments is not only the significant content of the healthcare system reform in China, but also the essential approach to better satisfying the Chinese growing demand for medical services. Performance management is vital and meaningful to public hospitals in China. Several studies are conducted in hospital internal performance management, but almost none of them consider the effects of informational tools. Therefore, we carried out an empirical study on effects of using performance management information system in Shanghai Ninth People's Hospital. The main feature of the system is that it provides a real-time query platform for users to analyze and dynamically monitor the key performance indexes, timely detect problems and make adjustments. We collected pivotal medical data on 35 clinical departments of this hospital from January 2013 until December 2014, 1 year before and after applying the performance management information system. Comparative analysis was conducted by statistical methods. The results show that the system is beneficial to improve performance scores of clinical departments and lower the proportion of drug expenses, meanwhile, shorten the average hospitalized days and increase the bed turnover rate. That is to say, with the increasing medical services, the quality and efficiency is greatly improved. In a word, application of the performance management information system has a positive effect on improving performance of clinical departments.

5.
Shanghai Kou Qiang Yi Xue ; 24(3): 331-4, 2015 Jun.
Artículo en Chino | MEDLINE | ID: mdl-26166523

RESUMEN

PURPOSE: To optimize visiting sequence and time-interval appointment mode to reduce waiting time of re-visiting patients in department of stomatology based on clinical data repository. METHODS: Waiting time data of re-visiting patients in department of stomatology was collected and divided into 2 groups. A total of 70897 patients from July 2014 to September 2014 were enrolled as experimental group (group year-2014), while 63960 patients from July 2013 to September 2013 were used as control group (group year-2013).Measurement data was compared with two-tailed independent-samples t test using SPSS 22.0 software package. RESULTS: The waiting time of group year-2014 was 73.65 minutes while it was 106 minutes for group year-2013. P value was 0,which meant the waiting time of group year-2014 was significantly less than group year-2013. CONCLUSIONS: Optimizing visiting sequence and time-interval appointment mode can reduce the waiting time of re-visiting patients in department of stomatology greatly. Supported by Innovation Research Training Project of Humanities and Social Sciences from Shanghai Jiao Tong University School of Medicine(wz1214).


Asunto(s)
Citas y Horarios , Humanos , Medicina Oral
6.
Shanghai Kou Qiang Yi Xue ; 24(6): 712-5, 2015 Dec.
Artículo en Chino | MEDLINE | ID: mdl-27063124

RESUMEN

PURPOSE: An optimal sequence algorithm model of divided period appointment consultation service was built through optimal sequence algorithm. METHODS: Re-visiting patients in the department of stomatology in a tertiary hospital were enrolled as the research objects in this study. Information about the diagnose term of common diseases, tooth positions treated, doctor's consultation hours were collected. After calculating the mean consultation hours of each disease based on the statistical analysis, the appointment consultation service sequence of re-visiting patients in the department of stomatology was optimized in accordance with the rule of "providing priority service to those requiring short consultation hours" by referencing to the theoretical model of parallel machine. RESULTS: The total waiting hours of patients after optimizing the appointment consultation sequence was decreased by 35.1%. CONCLUSIONS: Optimal sequence algorithm can optimize divided period consultation sequence, effectively shorten waiting hours and improve patients' medical experience.


Asunto(s)
Algoritmos , Medicina Oral , Derivación y Consulta/estadística & datos numéricos , Citas y Horarios , Humanos , Factores de Tiempo
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