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1.
Bull Entomol Res ; : 1-9, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32046801

RESUMO

Insecticide resistance is an increasing problem in citrus production. The Asian citrus psyllid, Diaphornia citri Kuwayama, is recognized as one of the most important citrus pests worldwide and it has developed resistance in areas where insecticides have been overused. The development of insecticide resistance is often associated with fitness costs that only become apparent in the absence of selection pressure. Here, the fitness costs associated with resistance to thiamethoxam and imidacloprid were investigated in three agricultural populations of D. citri as compared with susceptible laboratory colonies. Results showed that all field populations had greater resistance than laboratory susceptible colonies. For both thiamethoxam and imidacloprid, a Candidatus Liberibacter asiaticus-positive (CLas+) colony was more susceptible than the CLas- colony. Resistance ratios ranged from 7.65-16.11 for imidacloprid and 26.79-49.09 for thiamethoxam in field populations as compared with a susceptible, CLas- laboratory strain. Among three resistant field populations, a significantly reduced net reproductive rate and finite rate of population increase were observed in a population from Lake Wales, FL as compared to both susceptible strains. The fecundity of field populations from Lake Wales, FL was statistically lower than both laboratory susceptible populations. Certain changes in morphological characteristics were observed among resistant, as compared, with susceptible strains. Our data suggest fitness disadvantages associated with insecticide resistance in D. citri are related to both development and reproduction. The lower fitness of D. citri populations that exhibit resistance to neonicotinoid insecticides should promote recovery of sensitivity when those populations are no longer exposed to thiamethoxam and/or imidacloprid in the field. The results are congruent with a strategy of insecticide rotation for resistance management.

2.
J Biomater Sci Polym Ed ; : 1-18, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31724490

RESUMO

Biological modifications of the silk fibroin (silk) material have broad applications in textiles, biomedical materials and other industrial materials. It is economical to incorporate nanoparticles to the biosynthesis of silk fibroin by adding them to silkworm larval diets. This strategy may result in the rapid stable production of modified silk. Glucose-coated silver nanoparticles (AgNPs) were used to improve the AgNPs' biocompatibility, and the AgNPs were efficiently incorporated into silk by feeding. Larvae fed with AgNPs produced silk with significantly improved antibacterial properties and altered silk secondary structures. Both positive and negative effects on the growth and synthesis of silk proteins were observed after different AgNPs doses. Larvae feeding with low concentration of 0.02% and medium 0.20% AgNPs have greater transfer efficiencies of AgNPs to silk compared with feeding high concentration of 2.00% AgNPs. In addition, the elongation and tensile strength of the produced silk fibers were also significantly increased, with greater mammalian cell compatibility. The appropriate AgNPs concentration in the diet of silkworms can promote the synthesis of silk proteins, enhance their mechanical properties, improve their antibacterial property and inhibit the presence of Gram-negative bacteria.

3.
Int J Biol Sci ; 15(10): 2170-2181, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31592097

RESUMO

Hyperproteinemia is a severe metabolic disease characterized by abnormally elevated plasma protein concentrations (PPC). However, there is currently no reliable animal model for PPC, and the pathological mechanism of hyperproteinemia thus remains unclear. In this study, we evaluated the effects of hyperproteinemia on reproductive development in an invertebrate silkworm model with a controllable PPC and no primary disease effects. High PPC inhibited the synthesis of vitellogenin and 30K protein essential for female ovarian development in the fat body of metabolic tissues, and inhibited their transport through the hemolymph to the ovary. High PPC also induced programmed cell death in testis and ovary cells, slowed the development of germ cells, and significantly reduced the reproductive coefficient. Furthermore, the intensities and mechanisms of high-PPC-induced reproductive toxicity differed between sexes in this silkworm model.

4.
Insect Sci ; 26(5): 843-852, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29485745

RESUMO

The Asian citrus psyllid (Diaphorina citri Kuwayama) is known to exhibit abdominal color polymorphisms. In the current study, susceptibility to four insecticides was compared among orange/yellow, blue/green and gray/brown color morphs of field collected D. citri. The LD50 values and 95% fiducial limits were quantified for each insecticide and color morph combination and ranged between 0.10 ng/µL (0.06-0.10) and 6.16 ng/µL (3.30-12.50). Second, we measured the detoxification enzyme activity levels of orange/yellow, blue/green and gray/brown color morphs for cytochrome P450, glutathione S-transferase, and general esterase. The mean P450 activity (equivalent units) was significantly lower in gray/brown (0.152 ± 0.006) and blue/green morphs (0.149 ± 0.005) than in the orange/yellow morphs (0.179 ± 0.008). GST activity (µmol/min/mg protein) was significantly lower in the orange/yellow morph (299.70 ±1.24) than gray/brown (350.86 ± 1.19) and blue/green (412.25 ± 1.37) morphs. The mean EST activity (µmol/min/mg protein) was significantly higher in blue/green (416.72 ± 5.12) and gray/brown morphs (362.19 ± 4.69) than in the orange/yellow morphs (282.56 ± 2.93). Additionally, we analyzed the relative expression of assortment genes involved in cuticular melanization and basal immunity. The transcripts of Dopa Decarboxylase and Tyrosine Hydroxylase were expressed higher in blue/green and gray/brown than orange/yellow morphs. The transcription results paralleled the susceptibility of D. citri to organophosphate, neonicotinoid and pyrethroid insecticides. GST and EST activity may also be correlated with low levels of insecticide susceptibility. Cuticular melanization could be a factor for the development of resistance to insecticides among different color morphs.


Assuntos
Hemípteros/enzimologia , Hemípteros/genética , Resistência a Inseticidas/genética , Pigmentação/genética , Animais , Hemípteros/imunologia , Hemípteros/metabolismo , Imunidade Inata , Inativação Metabólica , Inseticidas/metabolismo , Polimorfismo Genético
5.
Front Physiol ; 9: 302, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29651251

RESUMO

Hyperproteinemia, which is characterized by an abnormally elevated plasma protein concentration (PPC), is a high-mortality, metabolic complication associated with severe liver and kidney disease. It is difficult to clinically distinguish the difference between the impacts of primary diseases and hyperproteinemia on tissues and organs, and there are no available animal models of hyperproteinemia. Here, we constructed an animal model of hyperproteinemia with a controllable PPC and no primary disease effects in the silkworm Bombyx mori that has attracted interest owing to its potential use in the pathological analysis of model animals. Silkworm have an open circulatory system in which each organ is directly immersed in hemolymph. The fat body (FB) of a silkworm, as a major organ for nutrient storage and energy metabolism, can effectively reflect hyperproteinemia-induced metabolic abnormalities in damaged visceral tissues. A pathogenesis study showed that hyperproteinemia attenuated cell autophagy and apoptosis by attenuating an endocrine hormone, thereby preventing FB remodeling during metamorphosis. Meanwhile, hyperproteinemia increased oxidative stress in the FB and resulted in a dysfunction of amino acid conversion. Supplementation with exogenous 20-hydroxyecdysone effectively mitigated the hyperproteinemia-mediated inhibition of FB remodeling.

6.
Insects ; 8(3)2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28930170

RESUMO

The Asian citrus psyllid, Diaphorina citri Kuwayma, is one of the most important pests in citrus production. The objective of this study was to evaluate D. citri resistance management with three insecticide rotations and compare them with no rotation and an untreated check. The different insecticides (modes of action) tested were: dimethoate, imidacloprid, diflubenzuron, abamectin 3% + thiamethoxam 13.9%, and fenpropathrin. Eggs, nymph, and adult psyllids were counted weekly. Five insecticide applications were made in 2016. Insecticide susceptibility was determined by direct comparison with a laboratory susceptible population and field populations before and after all treatments were applied. Rankings of eggs, nymphs, and adults counted in treated plots were significantly lower than in the untreated control plots after each application. Initially, the resistance ratio (RR50) for each rotation model, as compared with laboratory susceptible strain and the field population before application, was less than 5.76 and 4.31, respectively. However, after five applications with dimethoate, the RR50 using the laboratory and pre-treatment field populations was 42.34 and 34.74, respectively. Our results indicate that effectively rotating modes of action can delay and/or prevent development of insecticide resistance in populations of D. citri.

7.
Ecotoxicology ; 26(3): 351-359, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28116643

RESUMO

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), is a major pest of citrus trees worldwide. A wide variety of insecticides are used to manage D. citri populations within citrus groves in Florida. However, in areas shared by citrus growers and beekeepers the use of insecticides may increase the risks of Apis mellifera  L. (Hymenoptera: Apidae) loss and contaminated honey. The objective of this research was to determine the environmental toxicity of insecticides, spanning five different modes of action used to control D. citri, to A. mellifera. The insecticides investigated were imidacloprid, fenpropathrin, dimethoate, spinetoram and diflubenzuron. In laboratory experiments, LD50 values were determined and ranged from 0.10 to 0.53 ng/µl for imidacloprid, fenpropathrin, dimethoate and spinetoram. LD50 values for diflubenzuron were >1000 ng/µl. Also, a hazard quotient was determined and ranged from 1130.43 to 10893.27 for imidacloprid, fenpropathrin, dimethoate, and spinetoram. This quotient was <0.447 for diflubenzuron. In field experiments, residual activity of fenpropathrin and dimethoate applied to citrus caused significant mortality of A. mellifera 3 and 7 days after application. Spinetoram and imidacloprid were moderately toxic to A. mellifera at the recommended rates for D. citri. Diflubenzuron was not toxic to A. mellifera in the field as compared with untreated control plots. Phenoloxidase (PO) activity of A. mellifera was higher than in untreated controls when A. mellifera were exposed to 14 days old residues. The results indicate that diflubenzuron may be safe to apply in citrus when A. mellifera are foraging, while most insecticides used for management of D. citri in citrus are likely hazardous under various exposure scenarios.


Assuntos
Abelhas/fisiologia , Hemípteros/fisiologia , Controle de Insetos/métodos , Inseticidas/toxicidade , Animais , Citrus , Diflubenzuron/toxicidade , Dimetoato/toxicidade , Ecotoxicologia , Imidazóis/toxicidade , Macrolídeos/toxicidade , Neonicotinoides , Nitrocompostos/toxicidade , Piretrinas/toxicidade , Medição de Risco , Testes de Toxicidade
8.
Sci Rep ; 6: 19802, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-26806642

RESUMO

The use of quantum dots (QDs) in biological imaging applications and targeted drug delivery is expected to increase. However, the efficiency of QDs in drug targeting needs to be improved. Here, we show that amino acids linked to CdTe QDs significantly increased the targeted transfer efficiency and biological safety in the invertebrate model Bombyx mori. Compared with bare QDs530, the transfer efficiency of Ala- and Gly-conjugated QDs (QDs530-Ala and QDs530-Gly) in circulatory system increased by 2.6 ± 0.3 and 1.5 ± 0.3 times, and increased by 7.8 ± 0.9 and 2.9 ± 0.2 times in target tissue silk glands, respectively, after 24 h of QDs exposure. Meanwhile, the amount of conjugated QDs decreased by (68.4 ± 4.4)% and (46.7 ± 9.1)% in the non-target tissue fat body, and the speed at which they entered non-target circulating blood cells significantly decreased. The resultant QDs530-Ala revealed a better structural integrity in tissues and a longer retention time in hemolymph than that of QDs530 after exposure via the dorsal vessel. On the other hand, QDs530-Ala significantly reduced the toxicity to hemocytes, silk gland, and fat body, and reduced the amount of reactive oxygen species (ROS) in tissues.


Assuntos
Bombyx/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Pontos Quânticos/química , Aminoácidos/química , Animais , Compostos de Cádmio/química , Sobrevivência Celular/efeitos dos fármacos , Hemócitos/efeitos dos fármacos , Humanos , Invertebrados/efeitos dos fármacos , Modelos Animais , Pontos Quânticos/administração & dosagem , Espécies Reativas de Oxigênio/química , Telúrio/química
9.
Stat Med ; 32(8): 1294-312, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22903860

RESUMO

In many practical applications, count data often exhibit greater or less variability than allowed by the equality of mean and variance, referred to as overdispersion/underdispersion, and there are several reasons that may lead to the overdispersion/underdispersion such as zero inflation and mixture. Moreover, if the count data are distributed as a generalized Poisson or a negative binomial distribution that accommodates extra variation not explained by a simple Poisson or a binomial model, then the dispersion occurs too. In this paper, we deal with a class of two-component zero-inflated generalized Poisson mixture regression models to fit such data and propose a local influence measure procedure for model comparison and statistical diagnostics. At first, we formally develop a general model framework that unifies zero inflation, mixture as well as overdispersion/underdispersion simultaneously, and then we mainly investigate two types of perturbation schemes, the global and individual perturbation schemes, for perturbing various model assumptions and detecting influential observations. Also, we obtain the corresponding local influence measures. Our method is novel for count data analysis and can be used to explore these essential issues such as zero inflation, mixture, and dispersion related to zero-inflated generalized Poisson mixture models. On the basis of the results of model comparison, we could further conduct the sensitivity analysis of perturbation as well as hypothesis test with more accuracy. Finally, we employ here a simulation study and a real example to illustrate the proposed local influence measures.


Assuntos
Interpretação Estatística de Dados , Funções Verossimilhança , Modelos Estatísticos , Simulação por Computador , Humanos
10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 20(5): 1139-43, 2012 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-23114135

RESUMO

This study aimed to investigate the relationship between clinical features of myelodysplastic/myeloproliferative disease, unclassifiable (MDS/MPD-U), karyotype of chromosome and JAK2 mutation in 1 case. The clinical features, karyotype and JAK2 mutation of the patient with MDS/MPD-U were studied by means of bone marrow biopsy, karyotype analysis and ARMS-PCR technique. The results indicated that the typical micromegakaryocytes and thrombocytosis, karyotype aberration of trisomy 8 as well as JAK2 V617F mutation were found in this patient. It is concluded that the patient was diagnosed as MDS/MPD-U with trisomy 8 and JAK2 V617F mutation. The data of this patient will provide evidence for studying correlation of chromosome karyotype aberration with JAK2 V617F mutation and for evaluating prognosis of MDS/MPD-U.


Assuntos
Janus Quinase 2/genética , Doenças Mieloproliferativas-Mielodisplásicas/classificação , Doenças Mieloproliferativas-Mielodisplásicas/genética , Cromossomos Humanos Par 8 , Feminino , Humanos , Cariotipagem , Pessoa de Meia-Idade , Mutação , Trissomia
11.
Environ Pollut ; 164: 24-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22310058

RESUMO

Lange's metalmark butterfly, Apodemia mormo langei Comstock, is in danger of extinction due to loss of habitat caused by invasive exotic plants which are eliminating its food, naked stem buckwheat. Herbicides are being used to remove invasive weeds from the dunes; however, little is known about the potential effects of herbicides on butterflies. To address this concern we evaluated potential toxic effects of three herbicides on Behr's metalmark, a close relative of Lange's metalmark. First instars were exposed to recommended field rates of triclopyr, sethoxydim, and imazapyr. Life history parameters were recorded after exposure. These herbicides reduced the number of adults that emerged from pupation (24-36%). Each herbicide has a different mode of action. Therefore, we speculate that effects are due to inert ingredients or indirect effects on food plant quality. If these herbicides act the same in A. mormo langei, they may contribute to the decline of this species.


Assuntos
Borboletas/efeitos dos fármacos , Cicloexanonas/toxicidade , Glicolatos/toxicidade , Herbicidas/toxicidade , Imidazóis/toxicidade , Niacina/análogos & derivados , Animais , Espécies em Perigo de Extinção , Feminino , Masculino , Niacina/toxicidade
12.
Mol Vis ; 17: 2148-56, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21850190

RESUMO

PURPOSE: To investigate the inhibitory effects of anti-mouse interleukin-17 (IL-17) monoclonal antibody (mAb) in high-responder corneal allograft rejection. METHODS: C57BL/6 or BALB/c mice corneal grafts were grafted onto BALB/c hosts. The neutralizing mouse IL-17 antibody and isotype control were injected intraperitoneally immediately after transplantation for experimental treatment. At appropriate times after treatment, recipient grafts were assessed clinically and histologically, and recipient corneal graft- infiltrating cells were detected by immunohistochemistry and quantified by real-time PCR. The cytokine spleen levels of T helper type 1 (Th1), Th2, and Th17 were analyzed by enzyme-linked immunosorbent assay. Flow cytometric analysis was used to evaluate the frequencies of IL-17-producing Th17 cells. RESULTS: Neutralization of IL-17 with anti-IL-17 mAb obviously prolonged allograft survival compared to the group that received isotype control. Neovascularizations and inflammatory immune cells in corneal stroma decreased in the allogeneic recipients treated with anti-IL-17 mAb. The mRNA (mRNA) level of graft-infiltrating cells, including neutrophiles, cluster of differentiation 4 (CD4) T cells, and CD8 T cells, decreased dramatically in the IL-17 neutralization group. At days 14 and 42, splenocytes from recipients treated with anti-IL-17 mAb produced significantly less of the pro-inflammatory cytokines interferon-gamma (IFN-γ), IL-12p40, and IL-17 compared to those from control Ig-treated recipients at day 14. However, Th2 cytokine IL-4 and IL-5 production increased, and IL-13 levels were not significantly different among the three groups. IL-6 production was elevated in recipients treated with anti-IL-17 mAb. Anti-IL-17 mAb reduced the percentage of Th17 in CD4+ T cells, but there was no statistical significance between anti-IL-17 mAb and the control group. CONCLUSIONS: Neutralization of mouse IL-17 bioactivity with anti-IL-17 mAb improves allogeneic corneal graft survival and inhibits corneal allograft rejection to a certain extent by inhibiting production of graft-infiltrating inflammatory cells and decreasing the secretion of pro-inflammatory cytokines.


Assuntos
Anticorpos Monoclonais/farmacologia , Transplante de Córnea , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/efeitos dos fármacos , Interleucina-17/antagonistas & inibidores , Linfócitos T/imunologia , Animais , Anticorpos Monoclonais/uso terapêutico , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Sobrevivência de Enxerto/imunologia , Interferon gama/biossíntese , Interferon gama/imunologia , Subunidade p40 da Interleucina-12/biossíntese , Subunidade p40 da Interleucina-12/imunologia , Interleucina-13/biossíntese , Interleucina-13/imunologia , Interleucina-17/genética , Interleucina-17/imunologia , Interleucina-4/biossíntese , Interleucina-4/imunologia , Interleucina-5/biossíntese , Interleucina-5/imunologia , Interleucina-6/biossíntese , Interleucina-6/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , RNA Mensageiro/análise , Reação em Cadeia da Polimerase em Tempo Real , Baço/citologia , Baço/imunologia , Linfócitos T/citologia , Transplante Homólogo
13.
Nan Fang Yi Ke Da Xue Xue Bao ; 30(7): 1720-1, 1723, 2010 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-20650809

RESUMO

OBJECTIVE: To observe the effects of astragalosides on content of rat liver microsomal cytochrome P450 (CYP450), activity of glutathione-S-transferase (GST) and dimethylhydrazine (DMH)-induced aberrant crypt foci formation in rats. METHODS: Forty SD rats were randomly and equally divided into control group, Astragalus group, DMH group, Astragalus+DMH group. The animals were killed by off neck and the colorectal and liver tissues taken after treatment with astragalosides and dimethyl hydrazine . The colorectal tissues were stained by methylene blue, ACFs observed and counted, and liver microsomes isolated by differential centrifugation. The total enzyme content was detected by using differential spectrometry for carbon monoxide reduction. The glutathione (GSH) level was detected by using spectrophotometry to reflect the activity of the GST. RESULTS: The numbers of ACF and large ACF in Astragalus+DMH group were more significantly decreased than the DMH group (P<0.05). Compared with the control group, Astragalus group and Astragalus+DMH group, CYP450 level was decreased significantly, and GST activity increased significantly in DMH group (P<0.05). CONCLUSION: Astragalosides might reduce the number of colorectal aberrant crypt foci induced by dimethylhydrazine possibly by reducing the content of hepatic CYP450 and increasing GST activity in rats.


Assuntos
Focos de Criptas Aberrantes/metabolismo , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Saponinas/farmacologia , Animais , Neoplasias Colorretais , Dimetilidrazinas/toxicidade , Masculino , Microssomos Hepáticos/enzimologia , Ratos , Ratos Sprague-Dawley
14.
Ecotoxicology ; 19(6): 1124-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20405204

RESUMO

The effects of the tetramic acid insecticide, spirotetramat and the agricultural adjuvant, Destiny, were evaluated on the Cladoceran, Ceriodaphnia dubia. These compounds were evaluated separately and as a mixture because they can be applied together for control of certain crop pests and therefore have the potential to enter surface water as a binary mixture. Acute mortality estimates (48 h) were developed followed by chronic exposure (8 days) studies where several population parameters were recorded. Acute LC50 and 95% CL for spirotetramat and Destiny were estimated to be 23.8 (14.5-35.4) and 26.71 (20.8-34.0) mg/l, respectively. Thus, spirotetramat and Destiny were equitoxic to C. dubia at LC50. For the chronic population study, C. dubia populations were exposed to a range of concentrations for spirotetramat and Destiny singly and as a mixture. Each chemical alone reduced the number of founding individuals, offspring/female, final population size, and population growth rate in a concentration-dependent manner. However, exposure to the mixture caused significantly greater reductions in these parameters than either compound alone. These results indicate that agricultural adjuvants and pesticides may cause more damage to aquatic organisms as a mixture than either product alone. Therefore, future evaluations of pesticide effects should consider the effects of adjuvants as a mixture with pesticides when these products are recommended to be applied together for pest control.


Assuntos
Cladóceros/efeitos dos fármacos , Inseticidas/toxicidade , Sinergistas de Praguicidas/toxicidade , Pirrolidinonas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Cladóceros/fisiologia , Feminino , Dose Letal Mediana , Masculino , Crescimento Demográfico
15.
Ecotoxicol Environ Saf ; 73(2): 132-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19833391

RESUMO

The toxicity of the nonylphenol polyethoxylate, R-11 and the neonicotinoid insecticide, imidacloprid were evaluated on the crustacean, Ceriodaphnia dubia Richard. These compounds were evaluated separately and as a mixture because they are applied for pest control and may exist as a binary mixture in surface water. Acute mortality estimates (48h) were developed followed by population-level studies after chronic exposure. LC50s and 95% CL for R-11 and imidacloprid were 9241 (8521-9842)microg/l and 2.1 (1.1-3.4)microg/l, respectively. In the population study, C. dubia were exposed to concentrations equivalent to the acute LC25 for R-11 (8090microg/l) and imidacloprid (0.3microg/l) separately and as a mixture for 8d. The results of the chronic study indicated that R-11 had a greater impact on population parameters than imidacloprid and the mixture had a greater impact than either compound alone. For example, the total number of individuals at the end of the chronic study was 73%, 19%, and 6% of the control for imidacloprid, R-11, and the binary mixture, respectively. Additionally, exposure to R-11, imidacloprid, and the mixture resulted in 52%, 10%, and 91% reductions in population growth rate compared to the control, respectively. The results of this study indicate that when combined, R-11 and imidacloprid act in a more than additive manner. Therefore, it is important that their potential effects on aquatic organisms be evaluated together.


Assuntos
Cladóceros/efeitos dos fármacos , Inseticidas/toxicidade , Nonoxinol/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Cladóceros/crescimento & desenvolvimento , Relação Dose-Resposta a Droga , Monitoramento Ambiental , Imidazóis/toxicidade , Dose Letal Mediana , Mortalidade , Neonicotinoides , Nitrocompostos/toxicidade , Crescimento Demográfico , Fatores de Tempo
16.
Sensors (Basel) ; 9(6): 4986-5000, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-22408564

RESUMO

A high-frequency ultrasonic transducer for copper or gold wire bonding has been designed, analyzed, prototyped and tested. Modeling techniques were used in the design phase and a practical design procedure was established and used. The transducer was decomposed into its elementary components. For each component, an initial design was obtained with simulations using a finite elements model (FEM). Simulated ultrasonic modules were built and characterized experimentally through the Laser Doppler Vibrometer (LDV) and electrical resonance spectra. Compared with experimental data, the FEM could be iteratively adjusted and updated. Having achieved a remarkably highly-predictive FEM of the whole transducer, the design parameters could be tuned for the desired applications, then the transducer is fixed on the wire bonder with a complete holder clamping was calculated by the FEM. The approach to mount ultrasonic transducers on wire bonding machines also is of major importance for wire bonding in modern electronic packaging. The presented method can lead to obtaining a nearly complete decoupling clamper design of the transducer to the wire bonder.

17.
Artigo em Chinês | MEDLINE | ID: mdl-16927794

RESUMO

OBJECTIVE: To evaluate the clinical significance and application value of the real-time intraoperative monitoring (RTIM) technique in preventing recurrent laryngeal nerve (RLN) from injury during operation. METHODS: The RTIM of RLNs by nerve integrity monitor were used in 40 cases who underwent thyroid surgery under general anesthesia from Nov. 2002 to May 2005. The endotracheal intubation with laryngeal electrode sited on the tube nerve integrity monitor were adopted for general anesthesia. The RLNs in 7 cases who underwent thyroid gland lobectomy were exposed and explored and not exposed in other operations. RESULTS: The function of RLNs in 39 cases remained well after-operation. Only 1 patient's left RLN was damaged during operation. The spontaneous non-in-phase CMAP (compound muscle action potential) of larynx muscle in both vocal cords were recorded in all 40 cases who underwent thyroid surgery under general anesthesia. The evoked in-phase CMAP of larynx muscle could be recorded while stimulating the exposed and explored RLNs by monopolar electrode. The minimal stimulus current intensity threshold ranged from 0.08 mA to 0.35 mA (average: 0.25 mA). The range of suitable stimulating current intensity was from 0. 2 mA to 1.0 mA. CONCLUSIONS: This technology had been proved to be more sensitive, voracious and stable. It can provide fore part precaution so that remarkably reduce the damage rate of RLN in surgery and avoid the dispensable medical dissection. It is not necessary to anatomies RLN in surgery in advance.


Assuntos
Complicações Intraoperatórias/prevenção & controle , Monitorização Intraoperatória/métodos , Traumatismos do Nervo Laríngeo Recorrente , Doenças da Glândula Tireoide/cirurgia , Adulto , Idoso , Anestesia Geral , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tireoidectomia/métodos , Adulto Jovem
18.
Zhonghua Wai Ke Za Zhi ; 42(4): 233-5, 2004 Feb 22.
Artigo em Chinês | MEDLINE | ID: mdl-15062044

RESUMO

OBJECTIVE: To sum up the experience of carotid endarterectomy (CEA). METHODS: From January 1999 to July 2003, 59 patients were treated by CEA. There were 40 males and 19 females, and their age ranged from 56 to 79 years with an average of 71.8 years. The stenotic degree of internal carotid artery were over 80% in all cases. The left lesions were in 35 cases, and the right in 19, and the bilateral in 5. Patching were in 5, bypass with a great saphenous vein in 2. RESULTS: Fifty-five cases were excellent. Two patient died, one was caused by hyperperfusion syndrome, the another was due to the acute cardiac infarction at 31 days after operation. The complications included 5 hematosis and 1 hoarseness. CONCLUSION: CEA is still the best method in treating the stenosis and occlusion of carotid artery.


Assuntos
Arteriopatias Oclusivas/cirurgia , Estenose das Carótidas/cirurgia , Idoso , Artérias Carótidas , Endarterectomia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Resultado do Tratamento
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