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2.
J Phys Condens Matter ; 34(45)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36007519

RESUMO

The thermodynamic properties for bcc-Fe were predicted by combination of the first-principles calculations, the quasiharmonic approximation, the CALPHAD method and the Weiss molecular field theory. The hybrid method considers the effects of the lattice vibration, electron, intrinsic magnetism and external magnetic fields on the thermodynamic properties at finite temperature. Combined with experimental data, the calculated heat capacity without external magnetic fields was used to verify the validity of the hybrid method. Close to the Fermi level the high electronic density of states leads to a significant electronic contribution to free energy. Near the Curie temperature lattice vibrations dominant the Gibbs free energy. The order of the other three excitation contributions to Gibbs free energy from high to low is: intrinsic magnetism > electron > external magnetic fields. The investigation suggests that all the excitation contributions to Gibbs free energy are not negligible which provides a correct direction for tuning the thermodynamic properties for Fe-based alloy.

3.
Zhonghua Yi Xue Za Zhi ; 101(29): 2288-2292, 2021 Aug 03.
Artigo em Chinês | MEDLINE | ID: mdl-34333943

RESUMO

Objective: To investigate the emergency management process of ruptured abdominal aortic aneurysm (RAAA), and analyze the perioperative mortality factors of different surgical methods. Methods: The emergency data and hospitalization data of 91 patients with ruptured abdominal aortic aneurysm in Xiangya Hospital of Central South University from June 2010 to June 2019 were retrospectively analyzed.Twelve of the patients died preoperatively due to excessive blood loss, and the remaining 79 patients were hospitalized for open surgery (OSR) or endovascular repair (EVAR).The differences in age, time to hospital arrival, emergency preparation time, first creatinine value, emergency infusion volume, preoperative drop in blood pressure, preoperative use of vasoactive drugs and iliac artery involvement were compared between preoperative death group (n=12) and preoperative survival group (n=79), OSR group (n=50) and EVAR group (n=29), postoperative death group (n=23) and postoperative survival group (n=56). Results: Seventy-nine patients received open surgery or endovascular repair, and 23 died after operation. Age, time to hospital arrival, first creatinine value and emergency infusion volume were (77±11) years, (18±5)h, (469±150) µmol/L, (4 140±1 743) ml in the preoperative death group and (70±10) years, (12±8) h, (228±174) µmol/L, (1 358±1 211) ml in the preoperative survival group, respectively, and the differences were statistically significant (all P<0.05). There were no significant differences in preoperative data, intraoperative treatment and postoperative perioperative mortality between the open surgery group and the endovascular repair group (all P>0.05). The intraoperative blood loss, operation time and aortic occlusion rate in the endovascular repair group were 100 (50, 175) ml, (3.2±0.9) h, 13.8%, respectively, which were better than that in the open surgery group 1700 (600, 3425) ml, (5.2±1.1) h, 100%. The differences were statistically significant (all P<0.05). Age, emergency preparation time, first creatinine value, emergency infusion volume, blood pressure decline rate and vasoactive drug utilization rate in the death group were (77±8) years, (4.1±1.7) h, (456±172) µmol/L, (2 024±1 687) ml, 100%, 100%, respectively, and (68±10) years, (2.7±2.2) h, (135±26) µmol/L, (1 085±825) ml, 21.4%, 12.5% in the survival group, respectively. The differences were statistically significant (all P<0.05). Conclusions: Age, emergency preparation time, first creatinine value, emergency infusion volume, decreased blood pressure and use of vasoactive drugs are all associated with perioperative death in patients with ruptured abdominal aortic aneurysm. EVAR surgery is a better choice if conditions exist.


Assuntos
Aneurisma da Aorta Abdominal , Ruptura Aórtica , Implante de Prótese Vascular , Procedimentos Endovasculares , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/cirurgia , Tratamento de Emergência , Humanos , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
5.
Materials (Basel) ; 12(16)2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31430867

RESUMO

The effect of laser irradiation with different numbers of laser shots on the microstructure, the surface, and the hardness of gun metal alloy was studied by a KrF pulsed excimer laser system, X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and Vickers hardness test. The influence of 100-500 laser shots was irradiated on the surface hardness profile and on the microstructure of gunmetal alloy. XRD results showed the maximum 2θ shift, the maximum full width of half maximum FWHM, the maximum dislocation density, and the minimum crystallite size for the sample irradiated with 300 laser shots. The hardness was measured in three different regions at the laser irradiated spot, and it was found that maximum hardness was present at the heat affected zone for all samples. The hardness value of the un-irradiated sample of gun metal was 180, and the value increased up to 237 by raising the number of laser shots up to 300. The peak value of surface hardness of the laser treated sample was 32% higher than the un-irradiated sample. The Raman shift of the un-exposed sample was 605 cm-1 and shifted to a higher value of wave number at 635 cm-1 at 300 laser shots. The hardness value was decreased by further increasing the number of laser shots up to 500. The samples irradiated with 400 and 500 laser shots exhibited smaller hardness and dislocation defect density, which was assigned to possible annealing caused by irradiation.

6.
Eur Rev Med Pharmacol Sci ; 22(23): 8298-8305, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30556870

RESUMO

OBJECTIVE: To identify the potential role of miR-490-3p in the development of esophageal squamous cell carcinoma (ESCC), and to explore the possible underlying mechanism. PATIENTS AND METHODS: Human ESCC tissues and cancer-adjacent normal tissues were collected. The mRNA expression level of miR-490-3p was detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). On-line target gene prediction software was applied to screen high-mobility group AT-hook 2 (HMGA2). Subsequently, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide), qRT-PCR, Western blotting, transwell and scratch-wound assays were conducted to analyze the effect of miR-490-3p on the biological function of the ESCC cell line (EC-109). RESULTS: In our study, the mRNA expression level of miR-490-3p was remarkably reduced in ESCC tissues and cells. Molecular mechanism analysis confirmed that miR-490-3p could act on the 3'-UTR of HMGA2 and regulate its expression. Subsequent functional experiments indicated that decreased expression of HMGA2 resulting from the up-regulation of miR-490-3p could inhibit the proliferation, invasion, migration and epithelial-mesenchymal transition (EMT) of ESCC cells. CONCLUSIONS: We discovered the inhibitory effect of miR-490-3p on ESCC by targeting HMGA2, and revealed that miR-490-3p could be a potential therapeutic target for ESCC.


Assuntos
Movimento Celular , Proliferação de Células , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Proteína HMGA2/metabolismo , MicroRNAs/metabolismo , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/secundário , Regulação Neoplásica da Expressão Gênica , Proteína HMGA2/genética , Humanos , MicroRNAs/genética , Invasividade Neoplásica , Transdução de Sinais
7.
Sci Rep ; 8(1): 7884, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29760519

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

8.
Sci Rep ; 8(1): 3049, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29445201

RESUMO

Understanding the nature of the magnetic-field-induced precipitation behaviors represents a major step forward towards unravelling the real nature of interesting phenomena in Fe-based alloys and especially towards solving the key materials problem for the development of fusion energy. Experimental results indicate that the applied high magnetic field effectively promotes the precipitation of M23C6 carbides. We build an integrated method, which breaks through the limitations of zero temperature and zero external field, to concentrate on the dependence of the stability induced by the magnetic effect, excluding the thermal effect. We investigate the intimate relationship between the external field and the origins of various magnetics structural characteristics, which are derived from the interactions among the various Wyckoff sites of iron atoms, antiparallel spin of chromium and Fe-C bond distances. The high-magnetic-field-induced exchange coupling increases with the strength of the external field, which then causes an increase in the parallel magnetic moment. The stability of the alloy carbide M23C6 is more dependent on external field effects than thermal effects, whereas that of M2C, M3C and M7C3 is mainly determined by thermal effects.

9.
Bull Entomol Res ; 107(6): 715-723, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28274282

RESUMO

Macdunnoughia crassisigna Warren (Lepidoptera: Noctuidae) is a highly destructive herbivore that poses a serious risk to cotton, maize, soybean, and cruciferous vegetables in East Asia. Examining the effects of various biotic and abiotic factors on the flight performance of M. crassisigna is crucial for a better understanding of its trans-regional migration. In this study, the flight activity of M. crassisignai moths of different ages, under different temperatures and relative humidity (RH) levels, was evaluated by tethering individuals to computerized flight mills for a 24-h trial period. The results showed that M. crassisignai had the capacity for sustained flight and the flight ability was strongest in 3-day-old individuals, and then their flight performance decreased significantly in older moths. For both sexes, temperature had a significant effect on their flight performance, and the flight activity was relatively higher at 24-28°C than other temperatures. There was a significant effect of RH on all flight parameters of the tested moths, and the flight activity was relatively higher at RH of 60-75% than other RH levels. For 3-day-old moths under the optimum conditions (24°C and 75% RH) throughout the 24 h scotophase, their mean flight distance reached 66 km, and the mean flight duration reached 13.5 h, suggesting M. crassisigna possess strong potential to undertake long-distance migration. These findings will be helpful for developing sound forecasting systems of this pest species.


Assuntos
Voo Animal , Mariposas/fisiologia , Fatores Etários , Animais , Feminino , Umidade , Masculino , Fatores Sexuais , Temperatura
10.
Zhonghua Jie He He Hu Xi Za Zhi ; 39(11): 856-861, 2016 Nov 12.
Artigo em Chinês | MEDLINE | ID: mdl-27852361

RESUMO

Objective: To investigate the characteristics of lower airway abnormalities in allergic rhinitis(AR) patients without asthma. Methods: Between June 2008 and December 2012, 377 consecutive AR patients and 264 healthy subjects were recruited. All subjects underwent meticulous history taking, nasal examination, allergen skin prick test, blood routine test, serum total immunoglobin E assay, induced sputum cell count and differentials, measurement of fractional exhaled nitric oxide (FeNO) and bronchial challenge test. Results: The positive rates in AR patients was 12.2%(46/377) for bronchial provocation test, 49.2%(185/377) for FeNO, 39.0%(147/377) for sputum eosinophilia, 15.6%(40/377) for peripheral blood eosinophilia and 55.4%(209/377) for increased serum total IgE levels, which were consistently and statistically higher than those of healthy controls(P<0.01). The levels of FeNO [35.0 (21.8, 65.9)ppb], induced sputum eosinophil percentage [2.0 (0.0, 7.5)%], peripheral blood eosinophil percentage [2.9 (1.8, 4.5)%] and serum total IgE [178.4 (63.1, 384.0)kU/L] in AR patients were also higher(P<0.01). Compared with healthy controls, patients with AR demonstrated lower levels of FEV1/FVC%, MMEFpred%, MEF75 pred%, MEF25pred% (all P<0.05). Statistical analysis showed that FeNO, ratio of induced sputum eosinophil percentage and peripheral blood eosinophil percentage had significant correlations with each other(P<0.01), the r value being 0.247, 0.235, 0.355 respectively. Conclusion: AR without asthma is characterized by lower airway inflammation, small airway impairment and bronchial hyperreactivity, features similar to those of asthma.


Assuntos
Asma/imunologia , Hiper-Reatividade Brônquica/imunologia , Sistema Respiratório/fisiopatologia , Rinite Alérgica/imunologia , Rinite Alérgica/fisiopatologia , Rinite/fisiopatologia , Alérgenos/imunologia , Hiper-Reatividade Brônquica/diagnóstico , Testes de Provocação Brônquica , Eosinófilos , Expiração , Feminino , Humanos , Contagem de Leucócitos , Masculino , Óxido Nítrico , Testes de Função Respiratória , Testes Cutâneos , Escarro
11.
Artigo em Chinês | MEDLINE | ID: mdl-27666710

RESUMO

Objective: To summarize clinical experience on application of transoral robotic surgery (TORS) in pharyngeal tumour resection. Methods: Six patients underwent TORS with da Vinci® surgical system in our department from November 2013 to July 2015 and their clinical data were analyzed retrospectively. Results: TORS was accomplished successfully in all 6 patients. The surgical field-exposed time ranged from 30 to 40 minutes with an average of 35 minutes. The operative time ranged from 30 to 130 minutes with an average of 72 minutes. The hospital stays ranged from 6 to 14 days with an average of 10 days, and recovery time for oral intake ranged from 2 to 10 days with an average of 6 days. During TORS, the mouth gag needed to be adjusted 2 to 5 times. Surgical blood loss ranged from 5 to 30 ml with an average of 15 ml. No complications occurred during or after operation. Postoperative pathological examination of incisal edge in patients with malignant tumors showed no residual tumor cell. The mean follow-up was 14 months with no recurrence. Conclusion: With proper indications, TORS possesses enormous value to the application in otolaryngology-head and neck surgery.


Assuntos
Neoplasias Faríngeas/cirurgia , Procedimentos Cirúrgicos Robóticos/métodos , Perda Sanguínea Cirúrgica , Ingestão de Alimentos , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Prospectivos , Estudos Retrospectivos
12.
Bull Entomol Res ; 106(6): 740-748, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27296620

RESUMO

Heliothis viriplaca (Hüfnagel) (Lepidoptera: Noctuidae) is an important polyphagous pest of beans, cotton, maize, and alfalfa worldwide. H. viriplaca is a long-distance migrant, and if so, what pattern of seasonal migration this species exhibits in northern China remains unknown. In this study, in order to determine the seasonal migration of H. viriplaca in northern China, the combination of searchlight trapping and ovarian dissection was carried out on an isolated small island in the center of the Bohai Strait during 2003-2014. The results confirmed that H. viriplaca undertakes long-distance migration on the prevailing winds of the East Asian monsoon airflows. This species exhibited a regular pattern of seasonal migration across the sea from May to October, but there was considerable yearly and monthly variation in the trapped numbers, with the majority being trapped in summer (67.99 ± 6.54%). The mean period when migration was detectable at the island was 116.5 ± 5.6 days from 2003 to 2014, with the shortest time span of 74 days in 2013 and the longest of 144 days in 2005. Trapped females in May and June showed a relatively higher mating rates and some degree of ovarian development when compared with July, August and September, suggesting the migration of this species is not completely bound by the 'oogenesis-flight syndrome'. These findings will be helpful to improve the forecasting system and managing strategies of H. viriplaca.


Assuntos
Migração Animal , Mariposas/fisiologia , Animais , China , Feminino , Masculino , Mariposas/crescimento & desenvolvimento , Estações do Ano , Comportamento Sexual Animal , Maturidade Sexual , Vento
13.
Indian J Cancer ; 51 Suppl 2: e33-6, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25712840

RESUMO

OBJECTIVE: This study aimed to evaluate the outcome of benign vocal cord tumors treated using a laryngeal endoscopy under low temperature-controlled radiofrequency and to elucidate the application of a dynamic laryngoendoscopy in the operation. MATERIALS AND METHODS: 85 patients with benign vocal cord tumors were treated by laryngeal endoscopy under low temperature-controlled radiofrequency from September 2011 to October 2013. A XION electronic dynamic laryngoendoscopy (Germany) was used to observe curative effects 3 months after operation. Wave images were recorded with larynx-wave recording software to analyze tumor characteristics. RESULTS: Among the 85 patients, 81 showed smooth surface of operation wounds without any residue. The mucosal wave was also basically normal. Sound was generally recovered after 1-3 months. Three cases presented improved pronunciation function after the operation, whereas 1 patient with residual tumor at the front of vocal chords underwent another operation after 6 months. CONCLUSION: Low temperature-controlled radiofrequency exhibited many advantages, including minimal trauma, minimal bleeding, high safety, and few complications. Moreover, treatment of benign vocal cord tumors with a laryngeal endoscopy presented satisfactory outcomes. Therefore, this technology has broad application prospects.


Assuntos
Ablação por Cateter , Temperatura Baixa , Endoscopia/métodos , Neoplasias Laríngeas/cirurgia , Prega Vocal/patologia , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Neoplasias Laríngeas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Adulto Jovem
14.
Bull Entomol Res ; 104(5): 601-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24901755

RESUMO

The rice leaf roller, Cnaphalocrocis medinalis (Guenée), is a serious insect pest of rice with a strong migratory ability. Previous studies on the migration of C. medinalis were mostly carried out in tropical or subtropical regions, however, and what the pattern of seasonal movements this species exhibits in temperate regions (i.e. Northern China, where they cannot overwinter) remains unknown. Here we present data from an 11-year study of this species made by searchlight trapping on Beihuang Island (BH, 38°24'N; 120°55'E) in the centre of the Bohai Strait, which provides direct evidence that C. medinalis regularly migrates across this sea into northeastern agricultural region of China, and to take advantage of the abundant food resources there during the summer season. There was considerable seasonal variation in number of C. medinalis trapped on BH, and the migration period during 2003-2013 ranged from 72 to 122 days. Some females trapped in June and July showed a relatively higher proportion of mated and a degree of ovarian development suggesting that the migration of this species is not completely bound by the 'oogenesis-flight syndrome'. These findings revealed a new route for C. medinalis movements to and from Northeastern China, which will help us develop more effective management strategies against this pest.


Assuntos
Migração Animal , Mariposas/fisiologia , Animais , China , Feminino , Masculino , Oceanos e Mares , Dinâmica Populacional , Estações do Ano , Comportamento Sexual Animal , Maturidade Sexual
15.
Bull Entomol Res ; 104(4): 444-52, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24555504

RESUMO

Evolution of resistance to insecticides usually has fitness tradeoffs associated with adaptation to the stress. The basic regulation mechanism of tradeoff between reproduction and resistance evolution to Bacillus thuringiensis (Bt) toxin in the cotton bollworm, Helicoverpa armigera (Ha), based on the vitellogenin (Vg) gene expression was analyzed here. The full-length cDNA of the Vg gene HaVg (JX504706) was cloned and identified. HaVg has 5704 base pairs (bp) with an open reading frame (ORF) of 5265 bp, which encoded 1756 amino acid protein with a predicted molecular mass of 197.28 kDa and a proposed isoelectric point of 8.74. Sequence alignment analysis indicated that the amino acid sequence of HaVg contained all of the conserved domains detected in the Vgs of the other insects and had a high similarity with the Vgs of the Lepidoptera insects, especially Noctuidae. The resistance level to Cry1Ac Bt toxin and relative HaVg mRNA expression levels among the following four groups: Cry1Ac-susceptible strain (96S), Cry1Ac-resistant strain fed on artificial diet with Bt toxin for 135 generations (BtR stands for the Cry1Ac Bt resistance), progeny of the Cry1Ac-resistant strain with a non-Bt-toxin artificial diet for 38 generations (CK1) and the direct descendants of the 135th-generation resistant larvae which were fed on an artificial diet without the Cry1Ac protein (CK2) were analyzed. Compared with the 96S strain, the resistance ratios of the BtR strain, the CK1 strain and the CK2 strain were 2917.15-, 2.15- and 2037.67-fold, respectively. The maximum relative HaVg mRNA expression levels of the BtR strain were approximately 50% less than that of the 96S strain, and the coming of maximum expression was delayed for approximately 4 days. The overall trend of the HaVg mRNA expression levels in the CK1 strain was similar to that in the 96S strain, and the overall trend of the HaVg mRNA expression levels in the CK2 strain was similar to that in the BtR strain. Our results suggest that the changes in reproduction due to the Bt-toxin resistance evolution in the BtR strain may be regulated by the Vg gene expression. The down-regulation of HaVg at the early stages resulted in a period of delayed reproduction and decreased fecundity in the BtR strain. This performance disappeared when the Bt-toxin selection pressure was lost.


Assuntos
Evolução Biológica , Regulação da Expressão Gênica/fisiologia , Resistência a Inseticidas/fisiologia , Mariposas/fisiologia , Reprodução/fisiologia , Vitelogeninas/metabolismo , Sequência de Aminoácidos , Análise de Variância , Animais , Bacillus thuringiensis/química , Toxinas Bacterianas/metabolismo , Sequência de Bases , Clonagem Molecular , Cruzamentos Genéticos , DNA Complementar/genética , Dados de Sequência Molecular , Mariposas/genética , Fases de Leitura Aberta/genética , Análise de Sequência de DNA , Vitelogeninas/genética
16.
Tumour Biol ; 35(2): 1637-40, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24194393

RESUMO

Several case-control studies on the relation between XRCC1 gene Arg399Gln polymorphism and laryngeal cancer do not have similar conclusions. To further evaluate the relation between the XRCC1 gene Arg399Gln polymorphism and laryngeal cancer, we selected seven case-control studies related to the XRCC1 gene Arg399Gln polymorphism and laryngeal cancer by searching MEDLINE, EMBase, Chinese Biomedical Literature Database, Chinese CNKI, and Wanfang database. We utilized Q test and I (2) test to test the heterogeneity between each study. The fixed effects model was utilized to calculate the odds ratio (OR) and 95 % confidence interval. The present study included 1,654 patients with laryngeal cancer and 2,377 cancer-free control subjects. By meta-analysis, we did not find any association of XRCC1 gene Arg399Gln polymorphism with laryngeal cancer (OR = 1.13, 95 % CI 0.81-1.58, P = 0.47). Therefore, we concluded that XRCC1 gene Arg399Gln polymorphism was not associated with laryngeal cancer.


Assuntos
Proteínas de Ligação a DNA/genética , Predisposição Genética para Doença , Neoplasias Laríngeas/genética , Povo Asiático/genética , Estudos de Casos e Controles , Estudos de Associação Genética , Humanos , Neoplasias Laríngeas/patologia , Polimorfismo de Nucleotídeo Único , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
17.
Neoplasma ; 61(2): 144-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24299310

RESUMO

Increased expression of STMN1 has been observed in many tumor forms, but its expression and potential biological role in pancreatic cancer is still unknown. In this study, we demonstrated that STMN1 was expressed to a large extent in pancreatic cancer tissues and cell lines as compared to normal pancreatic tissues. Suppression of STMN1 expression via transfection with STMN1-specific siRNA could not only significantly inhibit the proliferation, migration and invasion ability of Panc-1 cells, but also enhance the apoptosis of Panc-1 cells. In addition, downregulation of STMN1 obviously enhanced the acetylation level of α-tubulin. All these results indicated that STMN1 plays an important role in pancreatic cancer development, and might serve as a potential therapeutic target for pancreatic cancer.


Assuntos
Apoptose/genética , Proliferação de Células , Neoplasias Pancreáticas/metabolismo , Estatmina/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Interferência de RNA , RNA Interferente Pequeno , Estatmina/metabolismo
18.
Int J Tuberc Lung Dis ; 13(4): 472-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19335953

RESUMO

SETTING: Many hospitals use the fully-automated BACTEC 960 Mycobacteria Growth Indicator Tube (MGIT) system and acid-fast staining to detect acid-fast bacilli (AFB) in clinical specimens; however, labour-intensive biochemical methods are used for further mycobacterial species identification. OBJECTIVE: To develop a user-friendly algorithm for mycobacterial species identification from AFB smear-positive BACTEC tubes. DESIGN: AFB smear-positive BACTEC tubes were collected and mycobacteria were isolated and identified by biochemical methods. The tubes were subgrouped by rpoB duplex polymerase chain reaction restriction enzyme analysis (rpoB DPRA). The results were combined with key phenotypic characters of mycobacteria isolated from the tubes to develop a species identification algorithm with 16S rDNA sequencing of the isolate being used as the gold standard method. RESULTS: By rpoB DPRA, 441 AFB smear-positive BACTEC tubes were correctly subgrouped into 100 tubes containing Mycobacterium tuberculosis complex, 335 tubes containing non-tuberculous mycobacteria and six tubes containing both. A species identification algorithm was developed by combining the rpoB DPRA results of the tubes with growth rate, photoreactivity and two biochemical results of mycobacteria recovered from the tubes. CONCLUSION: This user-friendly algorithm can be used for mycobacterial species identification from AFB smear-positive BACTEC tubes.


Assuntos
Técnicas Bacteriológicas , Mycobacterium tuberculosis/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Mapeamento por Restrição/métodos , Algoritmos , Técnicas Bacteriológicas/métodos , Enzimas de Restrição do DNA , DNA Bacteriano/análise , Mycobacterium tuberculosis/genética , Fenótipo , Taiwan
19.
Int J Tuberc Lung Dis ; 13(3): 371-6, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19275799

RESUMO

SETTING: Many hospitals in Taiwan use the fully automated BACTEC Mycobacterial Growth Indicator Tube (MGIT) 960 system to identify mycobacteria in clinical specimens, while the labour-intensive BD ProbeTec ET (CTB) system or biochemical methods are used to identify Mycobacterium tuberculosis complex (MTC) in mycobacterially positive BACTEC cultures. OBJECTIVE: To evaluate whether the Capilia TB assay can be used to replace the BD ProbeTec ET (CTB) system or biochemical methods for identifying MTC in BACTEC cultures. DESIGN: Mycobacterially positive BACTEC cultures were collected and MTC in the cultures was identified using biochemical methods. MTC was identified using serpentine cording in smears, the Capilia TB assay or the BD ProbeTec ET (CTB) system, and the results were compared. RESULTS: Using 233 mycobacterially positive BACTEC cultures, the sensitivity and specificity of identification of the Capilia TB assay were respectively 96.9% and 98.6%, while those of the BD ProbeTec ET (CTB) system were respectively 99.4% and 97.3%. Combining the Capilia TB assay with serpentine cording in smears led to 100% specificity for intersected results and 100% sensitivity for combined results. CONCLUSION: The Capilia TB assay can be used to identify MTC in BACTEC cultures. By combining the assay with serpentine cording in smears, false-positives and -negatives may be reduced.


Assuntos
Imunoensaio/métodos , Mycobacterium tuberculosis/classificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Antígenos de Bactérias/análise , Antígenos de Bactérias/isolamento & purificação , Proteínas de Bactérias/análise , Proteínas de Bactérias/isolamento & purificação , Cromatografia/métodos , Humanos , Mycobacterium tuberculosis/imunologia , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade , Tuberculose Pulmonar/diagnóstico
20.
Bull Entomol Res ; 99(6): 543-50, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19222869

RESUMO

The massive adoption of Bt cotton throughout China has been accompanied by outbreaks of secondary pests such as Adelphocoris spp. (Heteroptera: Miridae). The Adelphocoris group primarily consists of three species: A. suturalis, A. fasciaticollis and A. lineolatus, which greatly differ in geographical distribution and seasonal dynamics. However, the underlying drivers of these differences remain to be understood. The study of flight behaviour of these three species can yield important insight into their spatial and temporal dynamics and help explain their distribution. We examined flight propensity of the three Adelphocoris spp. under a range of biological and environmental conditions using a computer-monitored flight-mill. Gender and mating status only had minor effects on flight performance in these species, while age exerted great effects on it. Flight capacity was low for one-day-old adults and increased with age until day 10-13, then gradually decreased afterwards. Temperature and relative humidity affected flight propensity, with 20-23 degrees C and 64-68% RH considered optimal for flight of all three species. Between-species comparisons indicated that A. suturalis and A. fasciaticollis had similar flight distance and duration, which were significantly greater than for A. lineolatus. Our findings provide crucial information for understanding geographical distribution and seasonal occurrence and for developing regional forecasting and pest management protocols for Adelphocoris species.


Assuntos
Voo Animal , Gossypium/genética , Heterópteros/fisiologia , Animais , Bacillus thuringiensis/genética , China , Feminino , Geografia , Umidade , Masculino , Plantas Geneticamente Modificadas , Estações do Ano , Comportamento Sexual Animal , Especificidade da Espécie , Temperatura , Fatores de Tempo
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