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1.
Zhonghua Nei Ke Za Zhi ; 62(4): 374-383, 2023 Apr 01.
Article Zh | MEDLINE | ID: mdl-37032132

Objectives: To investigated the safety and efficacy of treating patients with acute non-ST-segment elevation myocardial infarction (NSTEMI) and elevated levels of N-terminal pro-hormone B-type natriuretic peptide (NT-proBNP) with levosimendan within 24 hours of first medical contact (FMC). Methods: This multicenter, open-label, block-randomized controlled trial (NCT03189901) investigated the safety and efficacy of levosimendan as an early management strategy of acute heart failure (EMS-AHF) for patients with NSTEMI and high NT-proBNP levels. This study included 255 patients with NSTEMI and elevated NT-proBNP levels, including 142 males and 113 females with a median age of 65 (58-70) years, and were admitted in the emergency or outpatient departments at 14 medical centers in China between October 2017 and October 2021. The patients were randomly divided into a levosimendan group (n=129) and a control group (n=126). The primary outcome measure was NT-proBNP levels on day 3 of treatment and changes in the NT-proBNP levels from baseline on day 5 after randomization. The secondary outcome measures included the proportion of patients with more than 30% reduction in NT-proBNP levels from baseline, major adverse cardiovascular events (MACE) during hospitalization and at 6 months after hospitalization, safety during the treatment, and health economics indices. The measurement data parameters between groups were compared using the t-test or the non-parametric test. The count data parameters were compared between groups using the χ² test. Results: On day 3, the NT-proBNP levels in the levosimendan group were lower than the control group but were statistically insignificant [866 (455, 1 960) vs. 1 118 (459, 2 417) ng/L, Z=-1.25,P=0.21]. However, on day 5, changes in the NT-proBNP levels from baseline in the levosimendan group were significantly higher than the control group [67.6% (33.8%,82.5%)vs.54.8% (7.3%,77.9%), Z=-2.14, P=0.03]. There were no significant differences in the proportion of patients with more than 30% reduction in the NT-proBNP levels on day 5 between the levosimendan and the control groups [77.5% (100/129) vs. 69.0% (87/126), χ²=2.34, P=0.13]. Furthermore, incidences of MACE did not show any significant differences between the two groups during hospitalization [4.7% (6/129) vs. 7.1% (9/126), χ²=0.72, P=0.40] and at 6 months [14.7% (19/129) vs. 12.7% (16/126), χ²=0.22, P=0.64]. Four cardiac deaths were reported in the control group during hospitalization [0 (0/129) vs. 3.2% (4/126), P=0.06]. However, 6-month survival rates were comparable between the two groups (log-rank test, P=0.18). Moreover, adverse events or serious adverse events such as shock, ventricular fibrillation, and ventricular tachycardia were not reported in both the groups during levosimendan treatment (days 0-1). The total cost of hospitalization [34 591.00(15 527.46,59 324.80) vs. 37 144.65(16 066.90,63 919.00)yuan, Z=-0.26, P=0.80] and the total length of hospitalization [9 (8, 12) vs. 10 (7, 13) days, Z=0.72, P=0.72] were lower for patients in the levosimendan group compared to those in the control group, but did not show statistically significant differences. Conclusions: Early administration of levosimendan reduced NT-proBNP levels in NSTEMI patients with elevated NT-proBNP and did not increase the total cost and length of hospitalization, but did not significantly improve MACE during hospitalization or at 6 months.


Heart Failure , Non-ST Elevated Myocardial Infarction , Male , Female , Humans , Aged , Natriuretic Peptide, Brain , Simendan/therapeutic use , Heart Failure/drug therapy , Peptide Fragments , Arrhythmias, Cardiac , Biomarkers , Prognosis
2.
Zhonghua Xin Xue Guan Bing Za Zhi ; 49(9): 856-865, 2021 Sep 24.
Article Zh | MEDLINE | ID: mdl-34530592

Objective: To analyze the current status, trend and predictors of thromboembolism risk assessment in patients hospitalized with non-valvular atrial fibrillation (NVAF) in tertiary hospitals in China. Methods: The study was based on data from the Improving Care for Cardiovascular disease in China (CCC)-Atrial Fibrillation (AF) project. About 10% of the tertiary hospitals in each geographic-economic stratum were recruited. Participating hospitals reported the first 10 to 20 patients with a discharge diagnosis of atrial fibrillation monthly. From February 2015 to December 2019, a total of 49 104 NVAF patients from 151 tertiary hospitals in 30 provinces, municipalities and autonomous regions were enrolled. Clinical data of the patients was collected. The proportion of NVAF patients receiving thromboembolism risk assessment, variations in the proportion between different hospitals, the time trend of the application of thromboembolism risk assessment, and the predictors of the application of thromboembolism risk assessment were analyzed. Results: The age of the NVAF patients was (68.7±12.1) years, 27 709 patients (56.4%) were male. Only 17 251 patients (35.1%) received thromboembolism risk assessment. The proportion varied substantially between hospitals with the lowest value of 0 and the highest value of 100%. Among the hospitals, which enrolled more than 30 patients, no patients received thromboembolism risk assessment in 18.4% (26/141) of the hospitals, more than 50% of the patients received thromboembolism risk assessment in 21.3% (30/141) of the hospitals, and all the patients received thromboembolism risk assessment in only 1 hospital. The proportion of NVAF patients receiving thromboembolism risk assessment was 16.2% (220/1 362) in the first quarter of 2015, and significantly increased to 67.1% (1 054/1 572) in the last quarter of 2019 (P<0.001). Patients' characteristics were associated with the application of thromboembolism risk assessment. The odds of receiving thromboembolism risk assessment was lower in male patients compared to female patients(OR=0.94,95%CI 0.89-0.99), lower in patients with acute coronary syndrome or other cardiovascular diseases compared to those with AF as the primary admission reason (OR=0.59, 95%CI 0.55-0.63, OR=0.52, 95%CI 0.45-0.61, respectively), and lower in patients with paroxysmal, persistent and long-standing/permanent AF compared to those with first detected AF (OR=0.62, 95%CI 0.57-0.67, OR=0.72, 95%CI 0.66-0.79, OR=0.57, 95%CI 0.52-0.64, respectively). The odds was higher in patients with a history of hypertension, heart failure, stroke/TIA, and previous anticoagulant therapy compared to those without the above conditions (OR=1.17, 95%CI 1.11-1.23, OR=1.18, 95%CI 1.07-1.30, OR=1.17, 95%CI 1.08-1.27, OR=1.28, 95%CI 1.19-1.37, respectively) (P all<0.05). Conclusion: Thromboembolism risk assessment was underused in patients hospitalized with NVAF in tertiary hospitals in China, and there were substantial variations between hospitals in the application of thromboembolism risk assessment. The application of thromboembolism risk assessment in tertiary hospitals has been improved in recent years, but there is still plenty of room for future improvement. Patients' characteristics could affect the application of thromboembolism risk assessment in China.


Atrial Fibrillation , Stroke , Thromboembolism , Aged , Aged, 80 and over , Anticoagulants , Atrial Fibrillation/complications , Atrial Fibrillation/epidemiology , China/epidemiology , Female , Humans , Male , Middle Aged , Risk Assessment , Risk Factors , Tertiary Care Centers , Thromboembolism/epidemiology
3.
Epidemiol Infect ; 148: e141, 2020 07 06.
Article En | MEDLINE | ID: mdl-32624078

The pandemic of coronavirus disease 2019 (COVID-19) has posed serious challenges. It is vitally important to further clarify the epidemiological characteristics of the COVID-19 outbreak for future study and prevention and control measures. Epidemiological characteristics and spatial-temporal analysis were performed based on COVID-19 cases from 21 January 2020 to 1 March 2020 in Shandong Province, and close contacts were traced to construct transmission chains. A total of 758 laboratory-confirmed cases were reported in Shandong. The sex ratio was 1.27: 1 (M: F) and the median age was 42 (interquartile range: 32-55). The high-risk clusters were identified in the central, eastern and southern regions of Shandong from 25 January 2020 to 10 February 2020. We rebuilt 54 transmission chains involving 209 cases, of which 52.2% were family clusters, and three widespread infection chains were elaborated, occurring in Jining, Zaozhuang and Liaocheng, respectively. The geographical and temporal disparity may alert public health agencies to implement specific measures in regions with different risk, and should attach importance on how to avoid household and community transmission.


Coronavirus Infections/epidemiology , Coronavirus Infections/transmission , Pneumonia, Viral/epidemiology , Pneumonia, Viral/transmission , Adult , COVID-19 , China/epidemiology , Contact Tracing , Female , Geographic Information Systems , Humans , Male , Middle Aged , Pandemics , Time Factors
4.
Transbound Emerg Dis ; 65(4): 1078-1086, 2018 Aug.
Article En | MEDLINE | ID: mdl-29520988

Porcine reproductive and respiratory syndrome virus (PRRSV) is a major economically significant pathogen that has adversely affected China's swine industry. Currently, a novel type 2 PRRSV, called the NADC30-like strain, is epidemic in numerous provinces of China, and commercial vaccines provide limited protection for infected animals. The extensive recombination phenomenon among NADC30-like PRRSVs is identified as a unique molecular characteristic of the virus. However, our understanding of how recombination influences NADC30-like PRRSVs is largely inadequate. In this study, we analysed the genetic characteristics of a recombinant NADC30-like PRRSV (SC-d) and examined its pathogenicity compared with a non-recombinant NADC30-like PRRSV (SD-A19) and a highly pathogenic PRRSV (HuN4). SC-d has three discontinuous deletions in nsp2, consistent with NADC30 isolated from the United States in 2008. Furthermore, we identified four recombination breakpoints in the SC-d genome, which separated the SC-d genome into four regions (regions A, B, C and D). Regions A and C are closely related to the JXA1-like strain, one of the earliest Chinese HP-PRRSV strains, and regions B and D are closely related to the NADC30 strain. Moreover, SC-d inoculated piglets exhibited a persistent fever, moderate weight loss, mild thymus atrophy and obvious microscopic lung lesions. In summary, the recombinant NADC30-like PRRSV SC-d strain displayed a higher pathogenicity than the non-recombinant NADC30-like PRRSV SD-A19 strain; however, the pathogenicity of the NADC30-like PRRSV SC-d was lower compared with the HP-PRRSV HuN4 strain in piglets. Our findings demonstrate that recombination is responsible for the enormous genetic diversity and pathogenicity variance of the NADC30-like PRRSV in China. This study provides a theoretical basis for developing a more reasonable PRRSV control and prevention strategy.


Evolution, Molecular , Genome, Viral , Porcine Reproductive and Respiratory Syndrome/virology , Porcine respiratory and reproductive syndrome virus/classification , Porcine respiratory and reproductive syndrome virus/genetics , Recombination, Genetic , Amino Acid Sequence , Animals , China/epidemiology , Genetic Variation , Lung/virology , Molecular Sequence Data , Phylogeny , Porcine Reproductive and Respiratory Syndrome/epidemiology , Porcine respiratory and reproductive syndrome virus/pathogenicity , Real-Time Polymerase Chain Reaction/veterinary , Sequence Analysis, DNA , Swine , Viral Nonstructural Proteins/genetics , Virulence
5.
Bull Entomol Res ; 108(5): 645-657, 2018 Oct.
Article En | MEDLINE | ID: mdl-29198196

The bird cherry-oat aphid Rhopalosiphum padi (L.) is one of the most important wheat pests with polyphagia and autumn migrants. And, chemosensory genes were thought to play a key role in insect searching their hosts, food and mate. However, a systematic identification of the chemosensory genes in this pest has not been reported. Thus, in this study, we identified 14 odorant-binding proteins, nine chemosensory proteins, one sensory neuron membrane protein, 15 odorant receptors, 19 gustatory receptors and 16 ionotropic receptors from R. padi transcriptomes with a significantly similarity (E-value < 10-5) to known chemosensory genes in Acyrthosiphon pisum and Aphis gossypii. In addition, real-time quantitative polymerase chain reaction (RT-qPCR) was employed to determine the expression profiles of obtained genes. Among these obtained genes, we selected 23 chemosensory genes to analyze their expression patterns in different tissues, wing morphs and host plants. We found that except RpOBP1, RpOBP3, RpOBP4 and RpOBP5, the rest of the selected genes were highly expressed in the head with antennae compared with body without head and antennae. Besides that, the stimulation and depression of chemosensory genes by plant switch indicated that chemosensory genes might be involved in the plant suitability assessment. These results not only provide insights for the potential roles of chemosensory genes in plant search and perception of R. padi but also provide initial background information for the further research on the molecular mechanism of the polyphagia and autumn migrants of it. Furthermore, these chemosensory genes are also the candidate targets for pest management control in future.


Aphids/genetics , Insect Proteins/genetics , Receptors, Odorant/genetics , Amino Acid Sequence , Animals , Aphids/metabolism , Gene Expression Profiling , Insect Proteins/chemistry , Insect Proteins/metabolism , Phylogeny , Real-Time Polymerase Chain Reaction , Receptors, Odorant/chemistry , Receptors, Odorant/metabolism , Sequence Alignment
7.
Genet Mol Res ; 15(3)2016 Sep 23.
Article En | MEDLINE | ID: mdl-27706762

The complete genomic RNA of the Chinese sacbrood virus (CSBV) strain, which infects the honeybees in the Loess plateau, was sequenced and analyzed. The CSBV-SX strain contains 8705 nucleotides, which includes a single large open reading frame (99-8681 nucleotides) encoding 2860 amino acids. A novel efficient identification method was used to investigate the samples infected by CSBV. The putative amino acid sequence alignment analysis showed that, except for some normal well characterized domains such as RNA helicase, RNA protease, and RNA-dependent RNA polymerase domains, a calicivirus coat protein domain was identified at amino acids 493-564. Phylogenetic analysis indicated that CSBV-SX was closely related to CSBV-BJ, and this result was supported by nucleotide multiple sequence alignment and protein multiple sequence alignment analysis results. These differences in the CSBV-SX strain may be related to virus adaptation to the xerothermic, low relative humidity, and strong ultraviolet radiation conditions in the Loess Plateau.


Genome, Viral , Phylogeny , Picornaviridae/genetics , Picornaviridae/isolation & purification , Amino Acid Sequence , Animals , Base Sequence , Bees/virology , China , Picornaviridae/classification , Protein Domains , Reverse Transcriptase Polymerase Chain Reaction , Sequence Alignment , Viral Proteins/chemistry
8.
J Econ Entomol ; 109(6): 2290-2297, 2016 Dec 01.
Article En | MEDLINE | ID: mdl-27744284

Insect growth regulators (IGRs) disrupt the normal activity of the endocrine or hormone system of insects, affecting the development, reproduction, or metamorphosis of the target insects, and normally causing less detrimental effects to beneficial insects. The effects of three IGRs (pyriproxyfen, fenoxycarb, and buprofezin) on Encarsia formosa Gahan, an endoparasitoid of whiteflies, were determined using B. tabaci as a host. We assessed the effects of the IGRs on parasitoid's larval development, pupation, emergence, and contact effects of the dry residues on plant leaf and glass vial surface on adult mortality and parasitism. When the three IGRs were applied at larval stage, no or few larvae pupated in the pyriproxyfen treatments and the highest concentration of fenoxycarb, and a majority of larvae pupated in the buprofezin treatments; of those pupated, 62.3-88.1% became adults. When the IGRs were applied at the pupal stage, 2.3-17.5% developed to adults in the pyriproxyfen treatments, 59.7-89.0% in the fenoxycarb treatments, and 58.4-83.6% in the buprofezin treatments. The leaf residues of the IGRs had no appreciable effects on adults, whereas the residues on glass vial caused significantly lower adult survival than on plant leaves. The residues of pyriproxyfen and fenoxycarb slightly reduced parasitism as compared with buprofezin and controls. However, the rates of parasitoids that became adults were significantly lower, especially in the pyriproxyfen treatments. According to the standards of International Organization of Biological Control (IOBC), pyriproxyfen was harmful, while fenoxycarb and buprofezin were slightly or moderately harmful to larvae and harmless to E. formosa pupae.


Hemiptera/parasitology , Juvenile Hormones/pharmacology , Wasps/drug effects , Wasps/physiology , Animals , Female , Host-Parasite Interactions/drug effects , Larva/drug effects , Larva/physiology , Phenylcarbamates/pharmacology , Pupa/drug effects , Pupa/physiology , Pyridines/pharmacology , Thiadiazines/pharmacology , Wasps/growth & development
9.
Zhonghua Liu Xing Bing Xue Za Zhi ; 37(8): 1127-30, 2016 Aug 10.
Article Zh | MEDLINE | ID: mdl-27539346

OBJECTIVE: To understand the changing trends of immune-related diseases. Disease patterns from both pre-and post-immunization plan and after the immunization program were described, in order to provide evidence for the formulation and revision of immunization program and policy, in Ningxia Hui Autonomous Region. METHODS: According to the time order descriptive method was used to analyze and compare the reported data on infectious diseases in Ningxia, between 1958 and 2014. RESULTS: From 1958 to 2014, both incidence and mortality of infectious diseases and four diseases related to the immunization programs, in Ningxia appeared significantly low. Since the implementation of the immunization plan, the incidence and mortality of the 4 diseases declined significantly, with the average annual total incidence as 176.12/100 000 before the immunization plan dropped to 2.56/100 000 when the expanded immunization plan was put into practice. The incidence also showed a downward trend. Among diseases that under the immunization program, the incidence of measles appeared the highest, followed by pertussis. However, none of the case on diphtheria or polio appeared which was caused by the wild strains, in 1983 and 1994. CONCLUSION: After the implementation of the immunization plan, the immune-related diseases seemed to have been under well controlled. and with remarkable social benefit. Immunization programs appeared the most effective measures to control and eliminate the acute infectious diseases in the region.


Communicable Disease Control/trends , Immunization Programs , Immunization/statistics & numerical data , Mortality/trends , Vaccination/statistics & numerical data , China/epidemiology , Communicable Diseases/epidemiology , Humans , Incidence , Measles/epidemiology , Measles/prevention & control , Poliomyelitis/etiology , Poliomyelitis/prevention & control , Research Design , Whooping Cough/epidemiology , Whooping Cough/prevention & control
10.
Bull Entomol Res ; 105(4): 448-55, 2015 Aug.
Article En | MEDLINE | ID: mdl-25895741

Continuous ingestion of the phloem sap of plants by aphids can remove a significant amount of photoassimilates. Based on our earlier works, we hypothesized that due to the reduced aphid feeding time caused by antibiosis, wheat plants may achieve growth tolerance to aphids. We tested this hypothesis using three wheat cultivars, XY22 (Xiaoyan22), AK58 (Bainongaikang58) and XN979 (Xinong979) and the grain aphid, Sitobion avenae. In the choice test, S. avenae did not show any preference among the three wheat cultivars. However, S. avenae had a lower body weight and a lower intrinsic rate of increase when feeding on XY22 than on AK58 and XN979. The electrical penetration graph results indicated that S. avenae had significantly shorter mean and total phloem ingestion periods on XY22 than on AK58 or XN979. The aphids required a similar time to reach the phloem sap on the three wheat cultivars, but required more time to establish sustained phloem ingestion on XY22. These results suggest that the resistance factors of XY22 may be phloem based. Moreover, XY22 suffered less biomass loss in response to aphid infestation compared with XN979, suggesting that XY22 also had a better growth tolerance to S. avenae than XN979. Wheat resistance level to S. avenae was partially correlated with plant photosynthetic rates, and peroxidase activities. These results confirmed that the limitation in aphid feeding from plant phloem in wheat cultivar XY22 was related to antibiosis but not antixenosis, which caused XY22 tolerance to S. avenae.


Antibiosis , Aphids/physiology , Triticum/genetics , Animals , Feeding Behavior , Pest Control, Biological , Plant Leaves/parasitology , Triticum/parasitology
11.
Ecotoxicology ; 22(3): 528-37, 2013 Apr.
Article En | MEDLINE | ID: mdl-23455995

Spiders are a principal arthropod group that preys on numerous pests of vegetables and other crops. In this study, we determined the effects of the two most commonly used insecticides, spinosad and λ-cyhalothrin, on diversity of spiders on cabbage in south Texas. In two seasons (fall 2008 and spring 2009), we collected a total of 588 spiders belonging to 53 species in 11 families from spinosad and λ-cyhalothrin-treated cabbages and the untreated control plants. A great majority of spiders were collected from the pitfall traps (554) where only a few (34) were collected from the blower/vacuum sampling. In the insecticide-treated plots, there were significantly fewer spider individuals, species and families than in untreated fields. Spinosad had significantly less effect on spiders in total individuals, number of species and families than λ-cyhalothrin. The effects of the two insecticides were further demonstrated by the Shannon-Weiner index (H') and the hierarchical richness index (HRI). Spider diversity in the spinosad-treated plots were not significantly different from that in the untreated fields but were greater than those in λ-cyhalothrin-treated plots in both seasons when measured by H' values. In contrast, the H' values of spider's diversity in the λ-cyhalothrin-treated plots were significantly lower than spinosad-treated and untreated plots. High values of HRI for spider richness in the spinosad-treated plots suggested that spinosad had less effect on spiders than λ-cyhalothrin. We concluded that spinosad was more compatible with spiders on cabbage compared to λ-cyhalothrin and that this information should be used when developing insecticide resistance management strategies.


Insecticides/toxicity , Macrolides/toxicity , Nitriles/toxicity , Pyrethrins/toxicity , Spiders/drug effects , Animals , Conservation of Natural Resources , Drug Combinations , Population Density , Population Dynamics , Species Specificity , Texas
12.
Plant Biol (Stuttg) ; 14(4): 612-20, 2012 Jul.
Article En | MEDLINE | ID: mdl-22188382

Although fast-growing Populus species consume a large amount of water for biomass production, there are considerable variations in water use efficiency (WUE) across different poplar species. To compare differences in growth, WUE and anatomical properties of leaf and xylem and to examine the relationship between photosynthesis/WUE and anatomical properties of leaf and xylem, cuttings of six poplar species were grown in a botanical garden. The growth performance, photosynthesis, intrinsic WUE (WUE(i) ), stable carbon isotope composition (δ(13) C) and anatomical properties of leaf and xylem were analysed in these poplar plants. Significant differences were found in growth, photosynthesis, WUE(i) and anatomical properties among the examined species. Populus cathayana was the clone with the fastest growth and the lowest WUE(i) /δ(13) C, whereas P. × euramericana had a considerable growth increment and the highest WUE(i) /δ(13) C. Among the analysed poplar species, the highest total stomatal density in P. cathayana was correlated with its highest stomatal conductance (g(s) ) and lowest WUE(i) /δ(13) C. Moreover, significant correlations were observed between WUE(i) and abaxial stomatal density and stem vessel lumen area. These data suggest that photosynthesis, WUE(i) and δ(13) C are associated with leaf and xylem anatomy and there are tradeoffs between growth and WUE(i) . It is anticipated that some poplar species, e.g. P. × euramericana, are better candidates for water-limited regions and others, e.g. P. cathayana, may be better for water-abundant areas.


Photosynthesis , Plant Leaves/anatomy & histology , Populus/physiology , Water/physiology , Xylem/anatomy & histology , Carbon , Carbon Isotopes/analysis , Populus/growth & development
13.
J Agric Food Chem ; 58(23): 12366-72, 2010 Dec 08.
Article En | MEDLINE | ID: mdl-21062044

This study presents a reductive transformation method that combines zerovalent iron (ZVI) and Aeromonas hydrophila HS01 with iron oxide reduction property to degrade DDT (1,1-trichloro-2,2-bis(4-chlorophenyl)ethane) under anoxic conditions. The results suggest that HS01 has weak capability in terms of reducing DDT to DDD (1,1-dichloro-2,2-bis(p-chlorophenyl)ethane) and nearly failed to reduce DDD or its transformed intermediates. The coexistence of ZVI and HS01 results in a slight enhancement of DDT degradation compared with the ZVI system alone. The reduction of intermediates by ZVI, however, can be obviously accelerated in the presence of HS01, and the addition of anthraquinone-2,6-disulfonic disodium salt (AQDS) can accelerate the transformation rates further, especially for intermediate reduction. The analysis of the amount and electrochemical properties of Fe(III)/Fe(II) indicates that the presence of HS01 with or without AQDS is beneficial to the reduction of Fe(III) to Fe(II), resulting in the removal of passivating ferric precipitates on the ZVI surface. A mechanism and pathway that clarify the roles of ZVI, HS01, and AQDS in the ZVI + HS01 + AQDS system for DDT transformation are proposed. The quick removal of surface ferric precipitates is thought to be the reason for the enhancement of the transformation of DDT and its intermediates.


Aeromonas hydrophila/metabolism , DDT/metabolism , Iron/metabolism , Biodegradation, Environmental , DDT/chemistry , Halogenation , Iron/chemistry , Molecular Structure , Oxidation-Reduction
14.
J Econ Entomol ; 103(3): 823-34, 2010 Jun.
Article En | MEDLINE | ID: mdl-20568629

Insect natural enemies can develop resistance to insecticides in the field like their host insects. Recently, a high level of resistance to several groups of insecticides from Pakistan has been shown in Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae). Here, we were interested to determine the impact of insecticides resistance on fitness of various populations of C. carnea collected over three consecutive years (2005-2007) from different areas of Pakistan. The populations were examined for intrinsic rate of population increase, growth index, fertility, eggs viability, survival to adult hood and doubling time. The results of the study showed significantly higher intrinsic rate of population increase in insecticides resistant population compared with laboratory susceptible population Lab-PK. Similarly, the resistant population laid more numbers of eggs, which were significantly more viable than susceptible population. The survival to adulthood and doubling time were greater in field populations than the susceptible. The most intriguing finding was that the predation potential of all resistant populations was significantly great compared with Lab-PK. The data point to the fact that resistance to insecticides had positive impact on C. carnea, which could be used in integrated pest management system. The potential for introducing these natural enemies into cropping systems where they have not developed resistance could be a useful tactic for management of various insect pests.


Insecta , Insecticides , Organophosphates , Predatory Behavior , Pyrethrins , Alleles , Animals , Insecta/genetics , Insecta/growth & development , Insecticide Resistance , Oviposition/genetics , Ovum , Selection, Genetic
15.
Environ Pollut ; 158(5): 1733-40, 2010 May.
Article En | MEDLINE | ID: mdl-20031285

The transformation of DDT was studied in an anaerobic system of dissimilatory iron-reducing bacteria (Shewanella decolorationis S12) and iron oxide (alpha-FeOOH). The results showed that S. decolorationis could reduce DDT into DDD, and DDT transformation rate was accelerated by the presence of alpha-FeOOH. DDD was observed as the primary transformation product, which was demonstrated to be transformed in the abiotic system of Fe(2+)+alpha-FeOOH and the system of DIRB+alpha-FeOOH. The intermediates of DDMS and DBP were detected after 9 months, likely suggesting that reductive dechlorination was the main dechlorination pathway of DDT in the iron-reducing system. The enhanced reductive dechlorination of DDT was mainly due to biogenic Fe(II) sorbed on the surface of alpha-FeOOH, which can serve as a mediator for the transformation of DDT. This study demonstrated the important role of DIRB and iron oxide on DDT and DDD transformation under anaerobic iron-reducing environments.


DDT/metabolism , Dichlorodiphenyldichloroethane/metabolism , Ferric Compounds/metabolism , Iron/metabolism , Shewanella/metabolism , Anaerobiosis , Biotransformation , Oxidation-Reduction
16.
Bull Entomol Res ; 99(3): 253-61, 2009 Jun.
Article En | MEDLINE | ID: mdl-18840315

The effects of Bt transgenic cottons (Bt-I expressing cry1Ac and Bt-II expressing cry1Ab and cry2Ab or cry1Ab and cry1Fa) and non-Bt cottons on feeding, oviposition and longevity of adults, and development and survival of Liriomyza trifolii larvae were studied under laboratory conditions; and infestation on four Bt and two non-Bt cotton traits were investigated under field conditions. Laboratory choice and no-choice tests showed that L. trifolii adults were capable of distinguishing between Bt cottons and non-Bt cottons. In a choice test on younger plants (4-5 leaves), the adults were found more often and made more feeding punctures (FP) on non-Bt cottons than on Bt cottons. On older plants (8-9 leaves), adults made the most FP on non-Bt cotton followed by those on Bt-II cottons and the least on Bt-I cotton. The females oviposited more eggs (6.7 eggs per leaf) on non-Bt cotton than on Bt-I (1.7 eggs per leaf) and Bt-II (0.8 eggs per leaf) cottons on younger plants and oviposited similar numbers of eggs (0.7-1.3 eggs per leaf) on non-Bt and Bt cottons on older plants. In a no-choice test, the females also fed more FP on non-Bt cottons than on Bt cottons on both younger and older plants. The females oviposited more eggs (15.6 eggs per leaf) on non-Bt cotton than on Bt-I (8.2 eggs per leaf) and Bt-II (6.5 eggs per leaf) cottons on younger plants and similar numbers of eggs (2.5-3.3 eggs per leaf) on non-Bt and Bt cottons on older plants. Larval and puparial survivals were not different among Bt and non-Bt cottons. The occurrence and damage of leafminers on cottons in the field showed that L. trifolii infested more plants and leaves and had more mines on non-Bt cotton than on Bt cottons.


Diptera/physiology , Feeding Behavior/physiology , Gossypium/parasitology , Oviposition/physiology , Animals , Bacillus thuringiensis Toxins , Bacterial Proteins/metabolism , Diptera/growth & development , Endotoxins/metabolism , Hemolysin Proteins/metabolism , Larva/growth & development , Larva/physiology , Plants, Genetically Modified , Texas
17.
Environ Entomol ; 37(6): 1396-402, 2008 Dec.
Article En | MEDLINE | ID: mdl-19161681

Effects of photoperiod on development, survival, feeding, and oviposition of boll weevils, Anthonomus grandis grandis Boheman, were assessed under five different photophases (24, 14, 12, 10, and 0 h) at a constant 27 degrees C temperature and 65% RH in the laboratory. Analyses of our results detected positive relationships between photoperiod and puncturing (mean numbers of oviposition and feeding punctures per day), and oviposition (oviposition punctures/oviposition+feeding punctures) activities, and the proportion of squares attacked by boll weevil females. When boll weevil females developed in light:darkness cycles, they produced a significantly higher percentage of eggs developing to adulthood than those developed in 24-h light or dark conditions. In long photoperiod (24:0 and 14:10 h), the number of female progeny was significantly higher and their development time was significantly shorter than those developed in short photoperiod (0:24 and 10:14 h). Lifetime oviposition was significantly highest at 12- and 14-h photophase, lowest at 0- and 10-h photophase, and intermediate at 24 h of light. Life table calculations indicated that boll weevil populations developed in a photoperiod of 14:10 and 12:12 (L:D) h will increase an average of two-fold each generation (Ro) compared with boll weevils developed in 24:0- and 10:14-h photoperiods and 15-fold compared with those at 0:24 h. Knowledge of the photoperiod-dependent population growth potential is critical for understanding population dynamics to better develop sampling protocols and timing insecticide applications.


Feeding Behavior , Oviposition , Photoperiod , Weevils/growth & development , Animals , Female , Male , Sex Ratio
18.
J Hazard Mater ; 149(1): 199-207, 2007 Oct 01.
Article En | MEDLINE | ID: mdl-17475402

To study the photodegradation of organic pollutants at the interface of minerals and water in natural environment, three series of alumina-coupled iron oxides (Al(2)O(3)-Fe(2)O(3)-300, Al(2)O(3)-Fe(2)O(3)-420, and Al(2)O(3)-Fe(2)O(3)-550) with different alumina fraction were prepared and characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) and Barret-Joyner-Halender (BJH), and Fourier transform infrared spectra (FTIR). The XRD results showed that existence of alumina in iron oxides could hinder the formation of maghemite and hematite, and also the crystal transformation from maghemite to hematite during sintering. It has been confirmed that the BET surface area and micropore surface area of Al(2)O(3)-Fe(2)O(3) catalysts increased with an increased dosage of alumina and with decreased sintering temperature. The pore size distribution also depended on the fraction of alumina. Furthermore, all Al(2)O(3)-Fe(2)O(3) catalysts had a mixed pore structure of micropore, mesopore and macropore. FTIR results showed that FTIR peaks attributable to Fe-O vibrations of maghemite or hematite were also affected by alumina content and sintering temperature. It was confirmed that the crystal structure and crystalline, the surface area and pore size distribution of Al(2)O(3)-Fe(2)O(3) catalysts depend strongly on the content of alumina and also sintering temperature. Bisphenol A (BPA) was selected as a model endocrine disruptor in aquatic environment. The effects of alumina on the photocatalytic activity of iron oxides for BPA degradation were investigated in aqueous suspension. The experimental results showed that the dependence of BPA degradation on the alumina content was attributable to the crystal structure, crystalline and also the properties of their surface structures. It was confirmed that the mixed crystal structure of maghemite and hematite could achieve the higher photocatalytic activity than maghemite or hematite alone.


Aluminum Oxide/chemistry , Ferric Compounds/chemistry , Phenols/chemistry , Phenols/radiation effects , Ultraviolet Rays , Benzhydryl Compounds , Catalysis , Endocrine Disruptors/chemistry , Endocrine Disruptors/radiation effects , Porosity , Surface Properties , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/radiation effects , Water Purification/methods
19.
Environ Entomol ; 36(2): 256-62, 2007 Apr.
Article En | MEDLINE | ID: mdl-17445359

The feeding and oviposition activity of overwintering boll weevils, Anthonomus grandis grandis (Boheman), and seasonal fluctuations in development, survival, and reproduction of progeny of overwintering and first- and second-generation boll weevil females were determined in the laboratory at 27 degrees C, 65% RH, and a photoperiod of 12:12 (L:D) h. During the cotton-free period in the Lower Rio Grande Valley, female boll weevils without access to cotton resorb their unlaid eggs and enter reproductive diapause. However, when they were provided daily with greenhouse-grown cotton squares, commencement of oviposition began after 7, 15, or 20 d, depending on when they were captured. Females captured later in the winter fed longer before laying eggs than those captured in the early fall, suggesting that it may take females longer to terminate diapause the longer they have been dormant. The rate of feeding by females was significantly less during the winter months, and this may have affected the rate of diet-mediated termination of dormancy. Females of the first and second generations after the overwintering generation produced a significantly higher percentage of progeny surviving to adulthood and a higher proportion of these progeny were females. Offspring development time from overwintering female parents was significantly longer than that from first and second generations under the same laboratory conditions. The total number of lifetime eggs produced by females of the second generation during the cotton-growing season were approximately 9.9-fold higher than for overwintering females and 1.5-fold higher than for first-generation females. Life table calculations indicated that the population of second-generation boll weevils increased an average of 1.5-fold higher each generation than for females of the first generation and 22.6-fold higher than for overwintering females. Our data showed variation in boll weevil survival, development, and reproductive potential among the overwintering and first- and second-generation females, suggesting inherent seasonal fluctuations in these parameters.


Animal Nutritional Physiological Phenomena , Oviposition/physiology , Reproduction/physiology , Weevils/physiology , Animals , Environment , Female , Gossypium , Photoperiod , Population Dynamics , Seasons , Time Factors , Weevils/growth & development
20.
J Colloid Interface Sci ; 311(2): 481-90, 2007 Jul 15.
Article En | MEDLINE | ID: mdl-17451730

To understand the degradation of endocrine disrupting chemicals (EDCs) with existence of iron oxides and polycarboxylic acids in the natural environment, the photodegradation of bisphenol A (BPA) at the interface of iron oxides under UV illumination was conducted. Four iron oxides were prepared by a hydrothermal process and then sintered at different temperatures of 65, 280, 310, and 420 degrees C named "IO-65," "IO-280," "IO-310," and "IO-420," respectively. The prepared iron oxides were characterized by X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) methods. The XRD pattern of IO-65 showed a crystal structure of lepidocrocite (gamma-FeOOH) and that of IO-420 demonstrated a crystal structure of hematite (alpha-Fe(2)O(3)), while IO-280 and IO-310 have the mixed crystal structures of maghemite (gamma-Fe(2)O(3)) and hematite. The BET results revealed that the specific surface areas decreased with the increase of sintering temperature. The results demonstrated that the photodegradation of BPA depends strongly on the properties of iron oxides and oxalate, and pH. The properties of iron oxides influenced strongly the dependence of the BPA degradation on the oxalate concentration. The optimal initial concentrations of oxalate for BPA degradation under UV illumination were determined to be 2.0, 2.0, 2.4, and 2.0 mM for IO-65, IO-280, IO-310, and IO-420, respectively. The first-order kinetic constants k for BPA degradation under UV illumination in the presence of oxalate with the optimal initial concentration are ranked as IO-280>IO-310>IO-65>IO-420. The experiments demonstrated that the optimal pH value should be in the range of 3-4. Furthermore, the dependence of BPA degradation should be also attributable to the formation of the dissolved Fe-oxalate in the solution and the adsorbed Fe-oxalate on the surface of iron oxides, and also the formation of hydrogen peroxide.


Estrogens, Non-Steroidal/chemistry , Ferric Compounds/chemistry , Oxalates/chemistry , Phenols/chemistry , Photolysis , Benzhydryl Compounds , Crystallization , Endocrine Disruptors/chemistry , Hydrogen-Ion Concentration , Kinetics , Solutions , Ultraviolet Rays , X-Ray Diffraction
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