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Crise Blástica , Dasatinibe , Leucemia Mielogênica Crônica BCR-ABL Positiva , Pirimidinas , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Pirimidinas/administração & dosagem , Dasatinibe/administração & dosagem , Masculino , Tiazóis/uso terapêutico , Tiazóis/administração & dosagem , Linfócitos T , Pessoa de Meia-Idade , FemininoRESUMO
Effective lasing mode control and unidirectional coupling of semiconductor microlasers are vital to boost their applications in optical interconnects, on-chip communication, and bio-sensors. In this study, symmetric and asymmetric GaN floating microdisks and coupled cavities are designed based on the Vernier effect and then fabricated via electron beam lithography, dry-etching of GaN, and isotropic wet-etching of silicon (Si) support. The lasing properties, including model number, threshold, radiation direction, and mode switching method, are studied. Compared to its symmetrical structure, both experimental and simulated optical field distributions indicate that the lasing outgoing direction can be controlled with a vertebral angle on the disk. The whispering gallery mode (WGM) lasing of the structures, with a quasi-single-mode lasing at 374.36 nm, a dual-mode lasing at 372.36 nm, and 373.64 nm at coupled cavities, are obtained statically. More interestingly, a switching between dual-mode and single-mode can be achieved dynamically via a thermal-induced mode shifting.
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Genetic factors are the main causes in occurrence of birth defects. With deep research in the field of genomics and application of molecular biology technology, the carrier status, fetal genetic variation and postpartum screening are respectively detected from pre-pregnancy, pregnancy and post-natal screening (before onset of disease) under perfect three-level prevention and control system for birth defects. Prospective detection, early diagnosis and intervention can prevent the occurrence of birth defects related to genetic diseases at multiple levels. This article describes and analyzes current clinical application and existing challenge of molecular biology techniques in prevention of birth defects related to genetic diseases.
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Biologia Molecular , Cuidado Pré-Natal , Feminino , Humanos , Gravidez , Estudos Prospectivos , Tecnologia , Prevenção TerciáriaRESUMO
Objective: To establish a disease risk prediction model for the newborn screening system of inherited metabolic diseases by artificial intelligence technology. Methods: This was a retrospectively study. Newborn screening data (n=5 907 547) from February 2010 to May 2019 from 31 hospitals in China and verified data (n=3 028) from 34 hospitals of the same period were collected to establish the artificial intelligence model for the prediction of inherited metabolic diseases in neonates. The validity of the artificial intelligence disease risk prediction model was verified by 360 814 newborns' screening data from January 2018 to September 2018 through a single-blind experiment. The effectiveness of the artificial intelligence disease risk prediction model was verified by comparing the detection rate of clinically confirmed cases, the positive rate of initial screening and the positive predictive value between the clinicians and the artificial intelligence prediction model of inherited metabolic diseases. Results: A total of 3 665 697 newborns' screening data were collected including 3 019 cases' positive data to establish the 16 artificial intelligence models for 32 inherited metabolic diseases. The single-blind experiment (n=360 814) showed that 45 clinically diagnosed infants were detected by both artificial intelligence model and clinicians. A total of 2 684 cases were positive in tandem mass spectrometry screening and 1 694 cases were with high risk in artificial intelligence prediction model of inherited metabolic diseases, with the positive rates of tandem 0.74% (2 684/360 814)and 0.46% (1 694/360 814), respectively. Compared to clinicians, the positive rate of newborns was reduced by 36.89% (990/2 684) after the application of the artificial intelligence model, and the positive predictive values of clinicians and artificial intelligence prediction model of inherited metabolic diseases were 1.68% (45/2 684) and 2.66% (45/1 694) respectively. Conclusion: An accurate, fast, and the lower false positive rate auxiliary diagnosis system for neonatal inherited metabolic diseases by artificial intelligence technology has been established, which may have an important clinical value.
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Doenças Metabólicas , Triagem Neonatal , Inteligência Artificial , China , Humanos , Lactente , Recém-Nascido , Estudos Retrospectivos , Método Simples-Cego , TecnologiaRESUMO
Objective: To establish a noninvasive method for measuring upper airway critical closing pressure (Pcrit), so as to evaluate collapsibility of the upper airway during sleep. Methods: Pcrit was determined through the use of a noninvasive positive/negative pressure (CPAP/CPNP) ventilator(with independent intellectual property rights) during stageâ ¡ of non-rapid eye movement sleep. For the direct measurement, Pcrit was the pressure below which the upper airway occluded. For the indirect measurement, nasal pressure was plotted against maximum inspiratory flow (Vimax), and linear regression was used to interpolate the pressure (i.e., Pcrit) at which zero flow occurred. Pcrit was attained from 19 subjects without obstructive sleep apnea syndrome(OSAS), and the correlation between direct and indirect measurement methods was analyzed. Results: Directly measured and indirectly measured Pcrit showed no significant difference [(-7.02±2.74 vs (-7.26±2.96) cmH2O, 1 cmH2O=0.098 kPa; t=1.667, P>0.05] and had a highly significant correlation (r=0.986, P=0.000). Bland-Altman analysis revealed that the mean between-method difference was (0.24±0.53) cmH2O, and 95% limits of agreement ranged from -0.80 to 1.27 cmH2O, and all points except one were within limits of agreement. Conclusion: Pcrit derived from the direct and indirect measurement methods does not differ, and both methods could be used for evaluating the upper airway collapsibility.
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Faringe , Apneia Obstrutiva do Sono , Pressão Positiva Contínua nas Vias Aéreas , Humanos , Polissonografia , Sono , Apneia Obstrutiva do Sono/diagnósticoRESUMO
Siglec-15 (S15) is another important mechanism of tumor immune escape besides the PD-L1/PD-1 pathway and represents a new kind of immune checkpoint inhibitor. However, the associations of tumor Siglec-15 expression with clinicopathological characteristics and outcomes of non-small cell lung cancer (NSCLC), and tumor-infiltrating lymphocytes (TILs) in a tumor microenvironment (TME) have so far been unclear. A total of 324 NSCLC surgical samples on tumor microarray were used in this study for investigating the association of S15 expression with clinicopathological characteristics and overall survival (OS) as well as correlation with TILs using multiplex immunofluorescence staining and PD-L1. Results showed that the expression of S15 in adenocarcinoma was significantly higher than that in squamous cell carcinoma. S15 expression was positively correlated with CD8+ T cell density in the stroma. The expression rate of PD-L1 in lung squamous cell carcinoma was higher than that in lung adenocarcinoma. S15 expression was not associated with the prognosis of early NSCLC. The pathological mechanism of the co-expression of S15 and PD-L1 in resectable NSCLC remains to be further studied.
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Carcinoma Pulmonar de Células não Pequenas , Imunoglobulinas/genética , Neoplasias Pulmonares , Proteínas de Membrana/genética , Antígeno B7-H1 , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/genética , Humanos , Neoplasias Pulmonares/genética , Linfócitos do Interstício Tumoral , Prognóstico , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico , Microambiente TumoralRESUMO
OBJECTIVE: This study aims to explore the expression of micro-ribonucleic acid (miRNA)-210 in the cerebral cortex of rat model with global cerebral ischemia, and determine its function on the regulation of the apoptosis of neuronal cells. MATERIALS AND METHODS: Rat models of global cerebral ischemia were established in vitro. Rats were euthanized at 24 h after reperfusion and the cerebral cortex was collected. The expression of miRNA-210 was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Neuronal cells were transfected by liposomes in vitro and cells were divided into neuronal cell group (group i), neuronal cell + miRNA-210 mimic group (group ii) and neuronal cell + miRNA-210 inhibitor group (group iii). The cell apoptosis rate and gene and protein expressions of HIF-1α, VEGF and Caspase-3 were measured. RESULTS: The level of miRNA-210 in rats with global cerebral ischemia was remarkably higher than that in rats from sham operation group (p<0.05). The apoptosis rate of neuronal cells was increased evidently when miRNA-210 was overexpressed, and the expressions of HIF-1α, VEGF and Caspase-3 were elevated markedly at both mRNA and protein levels. CONCLUSIONS: Our data indicate that miRNA-210 expression is upregulated in the rats with global cerebral ischemia, and the rise of miRNA-210 level increases the apoptosis of neuronal cells through the activation of HIF-1α-VEGF signaling pathway.
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Isquemia Encefálica/genética , Infarto Cerebral/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , MicroRNAs/genética , Neurônios/citologia , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Apoptose , Isquemia Encefálica/metabolismo , Células Cultivadas , Infarto Cerebral/metabolismo , Modelos Animais de Doenças , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Objective: By observing the clinical effect of ultrasound, fiberoptic bronchoscopy and traditional standard in positioning the general anesthesia of laryngeal mask ventilation in elderly patients, the superiority of laryngeal mask positioning with visualization technique of ultrasound and fiberoptic bronchoscope on airway management in elderly patients with general anesthesia was analyzed. Methods: One hundred and twenty cases of elderly patients with general anesthesia of laryngeal mask ventilation from the People's Hospital of Yuyao city from October 2016 to October 2017 were selected and randomly divided into 3 groups(n=40)according to American Society of Anesthesiologists (ASA) grading criteria â -â ¢. Group A: traditional standard positioning laryngeal mask group. Group B: fiberoptic bronchoscope positioning laryngeal mask group. Group C: ultrasound positioning laryngeal mask group. The general information of sex ratio of male and female, mass, and height, and operation type, operation duration, anaesthesia duration, and modified Mallampati grade were observed and compared among the three groups. The number of successful laryngeal mask ventilation after laryngeal mask placement in 3 groups was observed, the laryngeal mask placement time (T(0)) and the normal ventilation time after adjustment (T(1)) in each group were recorded, and the first success rate of laryngeal mask placement, the success rate after adjusting the positioning, and the success rate of re-placement were calculated. Moreover, the mean peak airway pressure at 5 min after operation, the minimum intrathecal injection gas for minimum ventilation (V(min)), the minimum laryngeal mask intravesical pressure (ICP(min)), and the lowest air pressure for oral and pharyngeal leakage (OLP(min)) were recorded. The airway seal pressure (OLP(60)) and the volume of gas injection (V(60)) when the intravesical pressure was 60 cmH(2)O (1 cmH(2)O=0.098 kPa) were used to record the incidence of postoperative laryngeal mask bleeding, cough, nausea and vomiting, and the incidence of pharyngalgia, odynophagia, hoarseness and other related complications after 24 hours of the operation. Results: There was no significant difference in general information, airway evaluation and anesthesia operation among the three groups (all P>0.05). The incidence of intraoperative laryngeal mask bleeding in group B and C was 7.9% and 2.6% respectively, the incidence of odynophagia at 24 hours after operation was 5.3% and 0 respectively, and the incidence of pharyngalgia and hoarseness was 18.4% and 7.9% respectively, less than that in group A (24.2%, 12.1% and 36.3%). The difference was statistically significant (χ(2)=8.900, 6.880, 9.000, P<0.05). The success rate of adjustment and positioning after the placement of laryngeal mask was 84.2% and 94.7% respectively in group B and C, higher than that in group A of 72.7%, and the difference was statistically significant (χ(2)=6.500, P<0.05). The lowest laryngeal mask intralaryngeal pressure for ventilation in group B and C was (35.39±4.67) cmH(2)O and (32.61±3.22) cmH(2)O, lower than that in group A of (39.30 ± 5.93) cmH(2)O, the intralaryngeal pressure was 60 cmH(2)O, and the airway seal pressure was (25.82±4.48) cmH(2)O and (28.34±6.99) cmH(2)O, higher than that in group A of (22.45±4.98) cmH(2)O, which was significantly different (F=18.200, 9.720, P<0.05). Conclusions: In elderly patients with general anesthesia, it is feasible to manage the airway by ultrasound or fiberoptic bronchoscopy with laryngeal mask. Ultrasound positioning laryngeal mask improves the accuracy of the intraoperative ventilation, and reduces the incidence of postoperative airway related complications.
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Máscaras Laríngeas , Idoso , Manuseio das Vias Aéreas , Anestesia Geral , Broncoscopia , Tosse , Feminino , Humanos , Masculino , FaringeRESUMO
Objective: To investigate the related factors for lymph node metastasis (LNM), especially for high volume LNM (>5 metastatic lymph nodes) in papillary thyroid carcinoma (PTC). Methods: The medical records of 2 073 consecutive PTC patients who underwent lobectomy, near-total thyroidectomy or total thyroidectomy with ipsilateral or bilateral central lymph node dissection in Department of General Surgery, Peking Union Medical College Hospital from November 2013 to October 2014 were reviewed. Clinical and pathological features were collected. Univariate and multivariate analysis were performed to identify the related factors for LNM/high volume LNM. Results: In all 2 073 patients, LNM and high volume LNM were confirmed in 936 (45.15%) cases and 254 (12.25%) cases respectively. In univariate analysis, large tumor size, young patients (<40 years), male were associated with both LNM and high volume LNM. In multivariate analysis, tumor size >2.0 cm, young patients (<40 years), male were independent related factors of LNM (OR=5.262, 95% CI: 3.468 to 7.986; OR=2.447, 95% CI: 2.000 to 2.995; OR=1.988, 95% CI: 1.593 to 2.480, respectively, all P=0.000) and high volume LNM (OR=6.687, 95% CI: 4.477 to 9.986; OR=2.975, 95% CI: 2.224 to 3.980; OR=2.354, 95% CI: 1.737 to 3.191, respectively, all P=0.000). In 1 414 PTMC patients, a similar result was also demonstrated.Compared with young patients (<40 years), old patients (≥60 years) had lower incidence of LNM (25.47% vs. 52.24%, χ(2)=62.903, P=0.000) and high volume LNM (1.89% vs. 13.18%, χ(2)=37.341, P=0.000). Additionally, old patients also had lower risk of both LNM (OR=0.316, 95% CI: 0.194 to 0.517, P=0.000) and high volume LNM (OR=0.142, 95% CI: 0.034 to 0.599, P=0.000). Conclusions: The tumor size was the main related factor for both LNM and high volume LNM in PTC. The treatment should be more active in patients with tumor size >2 cm with consideration of higher incidence and risk for LNM and high volume LNM. Young patient was another important related factor for LNM and high volume LNM. In PTMC, old patients had lower incidence and risk for both LNM and high volume LNM. Dynamic observation or less surgical extent could be an option for these patients.
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Metástase Linfática , Neoplasias da Glândula Tireoide , Adulto , Feminino , Humanos , Masculino , Estudos Retrospectivos , Fatores de Risco , Câncer Papilífero da Tireoide/patologia , Câncer Papilífero da Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , TireoidectomiaRESUMO
Creophilus maxillosus (L., 1758) is a common and widely distributed beetle species found on corpses, and its development duration is far longer than species belonging to the genus Calliphoridae and Sarcophagidae. Therefore, C. maxillosus can be used as a supplementary indicator to estimate minimum postmortem interval (PMImin), and could greatly extend the range of PMImin when the primary colonizers are no longer associated with the corpse or have emerged from pupae. Better descriptions of C. maxillosus development are needed to apply this species for forensic investigations. In this study, the development of C. maxillosus at seven constant temperatures ranging from 17.5-32.5 °C was studied. Through regression analyses, the simulation equations of larval body length variation with time after hatching were obtained. Isomegalen diagrams of the changes of larval body length over time at specific temperatures, and the isomorphen diagrams on the duration of different developmental milestones at specific temperatures were generated. In addition, thermal summation models of different developmental stages and the overall development process of C. maxillosus were generated through regression analysis, by estimating the development threshold temperatures (D0) and the thermal summation constants (K). These results provide important tools for forensic investigations to generate a long-range of PMImin estimation based on the development of C. maxillosus.
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Besouros/crescimento & desenvolvimento , Suínos/parasitologia , Animais , Tamanho Corporal , Cadáver , Feminino , Patologia Legal , Larva/crescimento & desenvolvimento , Masculino , Mudanças Depois da Morte , Pupa/crescimento & desenvolvimento , TemperaturaRESUMO
A case of a woman with twin pregnancy having placenta percreta involving the colon, showed hematochezia symptoms, experienced bleeding which caused the patient's mortality. Placenta percreta with bowel involvement is a very serious complication of pregnancy. Symptoms are very atypical and it is very difficult to diagnose.
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Colo , Placenta Acreta/cirurgia , Gravidez de Gêmeos , Adulto , Feminino , Humanos , Histerectomia , Placenta Acreta/patologia , GravidezRESUMO
Objective: To investigate the incidence, clinical, biochemical and gene mutation characteristics of short chain acyl-coenzyme A dehydrogenase deficiency (SCADD). Method: From January, 2009 to October, 2015, a retrospective analysis of the urine organic acids and acyl-coenzyme A dehydrogenase (ACADS) gene mutation characteristics of patients diagnosed as SCADD by newborn screening using tandem mass spectrometry in Department of Genetics and Metabolism (Newborn screening Center of Zhejiang Province), Children's Hospital, Zhejiang University School of Medicine. Dietary guidance, life management and supplementation of L-carnitine were conducted, and growth and intelligence development were observed during follow-up among the SCADD patients. Result: A total of 1 430 024 neonates, seventeen cases were diagnosed with SCADD with an incidence of 1/84 117. All patients had no clinical symptoms, and intelligence and physical development were normal. Blood butylacyl-carnitine (C4) levels and the ratios increased, C4 0.713.14 µmol/L(reference value 0.03-0.48 µmol/L), C4/C2 0.07-0.23(reference value 0.01-0.04), C4/C3 0.65-2.04(reference value 0.05-0.39). Thirteen with increased urinary ethyl malonic acid (9.30-90.99 mg/g creatinine (reference value 0-6.20 mg/g creatinine )), one patient was accompanied by increased methyl succinic acid (12.33 mg/g creatinine(reference value 0-6.40 mg/g creatinine)), one subject with increased acetylglycine (3.52 mg/g creatinine(reference value 0-0.70 mg/g creatinine)). A total of 13 known mutations were detected in the ACADS gene, 1 homozygous mutation (c.1031A>G), the others are compound heterozygous mutations. One frameshift mutation (c.508_509delGC) and 12 missense mutations were detected. Common mutation were c. 1031A>G(35.3%), c. 164C>T(20.6%) and c. 991G>A(11.8%). SCADD in newborn screening program had no clinical symptoms and normal growth development after 8-42 months follow-up. Conclusion: Cases with SCADD had no clinical symptoms with an incidence of 1/84117. The c. 164C>T and c. 1031A>G may be the common mutations.
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Acil-CoA Desidrogenase/deficiência , Erros Inatos do Metabolismo dos Aminoácidos/genética , Erros Inatos do Metabolismo Lipídico/genética , Triagem Neonatal/métodos , Acil-CoA Desidrogenase/sangue , Acil-CoA Desidrogenase/genética , Erros Inatos do Metabolismo dos Aminoácidos/sangue , Erros Inatos do Metabolismo dos Aminoácidos/etnologia , Carnitina/sangue , Criança , China/epidemiologia , Homozigoto , Humanos , Incidência , Recém-Nascido , Erros Inatos do Metabolismo Lipídico/sangue , Erros Inatos do Metabolismo Lipídico/etnologia , Masculino , Mutação , Estudos Retrospectivos , Espectrometria de Massas em TandemRESUMO
Molecular markers can increase both the efficiency and speed of breeding programs. Functional markers that detect the functional mutations causing phenotypic changes offer a precise method for genetic identification. In this study, we used newly derived cleaved amplified polymorphic sequence markers to detect the functional mutations of tms5, which is a male sterile gene that is widely used in rice production in China. In addition, restriction cutting sites were designed to specifically digest amplicons of tms5 but not wild type (TMS5), in order to avoid the risk of false positive results. By optimizing the condition of the polymerase chain reaction amplifications and restriction enzyme digestions, the newly designed markers could accurately distinguish between tms5 and TMS5. These markers can be applied in marker-assisted selection for breeding novel thermo-sensitive genic male sterile (TGMS) lines, as well as to rapidly identify the TGMS hybrid seed purity.
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Quimera/genética , Genes de Plantas , Marcadores Genéticos , Oryza/genética , Melhoramento Vegetal , Infertilidade das Plantas/genética , Mapeamento Cromossômico , Cruzamentos Genéticos , Primers do DNA/síntese química , Enzimas de Restrição do DNA/genética , Técnicas de Amplificação de Ácido Nucleico , Sementes/genéticaRESUMO
BACKGROUND: Tea is the world's most popular non-alcoholic beverage. China and India are known to be the largest tea producing countries and recognized as the centers for the domestication of the tea plant (Camellia sinensis (L.) O. Kuntze). However, molecular studies on the origin, domestication and relationships of the main teas, China type, Assam type and Cambod type are lacking. METHODOLOGY/PRINCIPAL FINDINGS: Twenty-three nuclear microsatellite markers were used to investigate the genetic diversity, relatedness, and domestication history of cultivated tea in both China and India. Based on a total of 392 samples, high levels of genetic diversity were observed for all tea types in both countries. The cultivars clustered into three distinct genetic groups (i.e. China tea, Chinese Assam tea and Indian Assam tea) based on STRUCTURE, PCoA and UPGMA analyses with significant pairwise genetic differentiation, corresponding well with their geographical distribution. A high proportion (30%) of the studied tea samples were shown to possess genetic admixtures of different tea types suggesting a hybrid origin for these samples, including the Cambod type. CONCLUSIONS: We demonstrate that Chinese Assam tea is a distinct genetic lineage from Indian Assam tea, and that China tea sampled from India was likely introduced from China directly. Our results further indicate that China type tea, Chinese Assam type tea and Indian Assam type tea are likely the result of three independent domestication events from three separate regions across China and India. Our findings have important implications for the conservation of genetic stocks, as well as future breeding programs.
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Camellia sinensis/classificação , Técnicas de Genotipagem/métodos , Repetições de Microssatélites , Camellia sinensis/genética , China , Domesticação , Variação Genética , Índia , Filogenia , Filogeografia , Sementes/genéticaRESUMO
Vast experiments have demonstrated that the external specimen size makes a large difference in the deformation behavior of crystalline materials. However, as one important kind of internal planar defects, the role of grain boundary (GB) in small scales needs to be clarified in light of the scarce and inconsistent experimental results at present. Through compression of Cu bicrystal and its counterpart monocrystal micropillars, it is found that, in contrast to the monocrystals, the bicrystals are characterized by work hardening with discrete strain bursts. Interestingly, the stress rise between two adjacent strain bursts of the bicrystals increases with the decrease of specimen size. The results suggest that GBs play a critical role in the work hardening of materials in small scales, which may provide important implications to further understand the general work hardening behaviors of materials in the future.
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A few insect control genes of Bacillus thuringiensis have been modified successfully to increase the expression in plants by replacing rare codons, increasing GC content, and avoiding the DNA elements that could cause premature transcription termination, mRNA instability, and potential methylation. However, the modification process was intricate and often confused researchers. In this study, we adopted a simple method to modify Cry1Ab only by individually replacing its amino acid sequence with corresponding rice-preferred codons based on analysis of 92,188 coding DNA sequences. Unexpectedly, all elements of A+T richness, which terminate or destabilize transcription in plants, were avoided in the newly designed mCry1Ab. However, mCry1Ab had 2 notable features: less synonymous codons and high GC content. mCry1Ab only employed 22 of the 61 codons to encode protein and had an enhanced GC content of 65%. The increase in GC content caused abundant potential methylation signals to emerge in mCry1Ab. To test whether mCry1Ab could be expressed in rice, we transferred it into Oryza japonica variety Wanjing97. Insect bioassays revealed that transgenic plants harboring this gene driven by 2 promoters, CaMV35S and OsTSP I, were highly resistant to rice leaffolder (Cnaphalocrocis medinalis). Analysis of R0 to R2 generation plants indicated that the mCry1Ab was inherited stably by the progeny. Our study provided a simple modified method for expressing exogenous genes in rice and confirmed that less synonymous codons and high GC content do not affect transgene expression in rice.
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Proteínas de Bactérias/genética , Endotoxinas/genética , Proteínas Hemolisinas/genética , Oryza/genética , Controle Biológico de Vetores , Plantas Geneticamente Modificadas/genética , Sequência de Aminoácidos , Animais , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis , Lepidópteros/patogenicidade , Oryza/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Regiões Promotoras GenéticasRESUMO
The aim of this study was to develop an event-specific qualitative and real-time quantitative polymerase chain reaction (PCR) method for detection of herbicide-tolerance genetically modified (GM) soybean A2704-12. The event-specific PCR primers were designed, based on the 5'-flanking integration sequence in the soybean genome, to amplify the 239-bp target fragment. Employing the same event-specific primers, qualitative PCR and real-time quantitative PCR detection methods were successfully developed. The results showed that the A2704-12 event could be specifically distinguished from other GM soybean events. In the qualitative PCR assay, the limit of detection was 0.05%, and in the real-time quantitative PCR assay, the limit of detection was less than 0.01%. Moreover, our genomic DNA (gDNA) extraction protocol is high-throughput, safe, and low-cost. The event-specific PCR assay system is cost-efficient by using SYBR Green I in real-time PCR, and by using the same primers in both the qualitative and quantitative PCR assays. We therefore developed a high-throughput, low-cost, and event-specific qualitative and quantitative PCR detection method for GM soybean A2704-12. The method would be useful for market supervision and management of GM soybean A2704-12 due to its high specificity and sensitivity.
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Glycine max/genética , Ensaios de Triagem em Larga Escala/métodos , Reação em Cadeia da Polimerase/métodos , Sequência de Bases , Herbicidas/toxicidade , Ensaios de Triagem em Larga Escala/economia , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Reação em Cadeia da Polimerase/economia , Glycine max/efeitos dos fármacos , Glycine max/crescimento & desenvolvimentoRESUMO
The uniaxial intermetallic compounds of L10-FePt and the low temperature NiAs structure of MnBi are suitable alloys for application as high-density recording materials or as high-coercivity permanent magnets. Single domain particles of these materials are characterized by coercive fields above 1 T over a large temperature range. In particular MnBi shows a coercive field of 2 T at 450 K. Its extraordinary magnetic properties in the temperature range up to 600 K are due to an increase of the magnetocrystalline anisotropy constant from 1.2 MJ m(-3) at 300 K to 2.4 MJ m(-3) at 450 K. In spite of the large coercivities obtained for both type of materials their experimental values deviate considerably from the theoretical values Hc = 2K1/Js valid for a homogeneous rotation process in spherical particles. As is well known these discrepancies are due to the deteriorating effects of the microstructure. For an analysis of the coercive fields the Stoner-Wohlfarth theory has to be expanded with respect to higher anisotropy constants and to microstructural effects such as misaligned grains and grain surfaces with reduced anisotropy constants. It is shown that the temperature dependence and the angular dependence of Hc for FePt as well as MnBi can be quantitatively interpreted by taking into account the above mentioned intrinsic and microstructural effects.
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Ligas/química , Dureza , Fenômenos Magnéticos , Metais Pesados/química , Nanopartículas/química , Bismuto/química , Ferro/química , Manganês/química , Platina/química , TemperaturaRESUMO
Low temperature is a major environmental stress in rice cultivating and production. The alternative oxidase 1 (AOX1) gene is potentially important for genetic engineering to increase cold adaptation. However, previous studies related to this effect have mostly focused on the dicot plants Arabidopsis and tobacco, whereas functional research on rice is limited. In this study, we cloned a rice predominant cold-response AOX1 gene, OsAOX1a. Transgenic rice plants with overexpression of OsAOX1a were obtained. We found that OsAOX1a overexpression could strongly enhance the cold growth of seedlings, especially with respect to root extension. However, growth between transgenic and control plants did not differ under normal conditions. Furthermore, the lipid peroxidation and ion leakage rate were determined after cold treatment in transgenic plants. Both factors were reduced by OsAOX1a overexpression, which revealed that OsAOX1a could reduce oxidative damage under cold stress. Taken together, our results suggested that overexpressing OsAOX1a could improve growth performance of rice under cold stress, which might be closely related to the reduction of reactive oxygen species generation and oxidative damage.