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1.
Int J Mol Sci ; 25(12)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38928068

RESUMO

As a low-calorie sugar, D-allulose is produced from D-fructose catalyzed by D-allulose 3-epimerase (DAE). Here, to improve the catalytic activity, stability, and processability of DAE, we reported a novel method by forming organic-inorganic hybrid nanoflowers (NF-DAEs) and co-immobilizing them on resins to form composites (Re-NF-DAEs). NF-DAEs were prepared by combining DAE with metal ions (Co2+, Cu2+, Zn2+, Ca2+, Ni2+, Fe2+, and Fe3+) in PBS buffer, and were analyzed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, and X-ray diffraction. All of the NF-DAEs showed higher catalytic activities than free DAE, and the NF-DAE with Ni2+ (NF-DAE-Ni) reached the highest relative activity of 218%. The NF-DAEs improved the thermal stability of DAE, and the longest half-life reached 228 min for NF-DAE-Co compared with 105 min for the free DAE at 55 °C. To further improve the recycling performance of the NF-DAEs in practical applications, we combined resins and NF-DAEs to form Re-NF-DAEs. Resins and NF-DAEs co-effected the performance of the composites, and ReA (LXTE-606 neutral hydrophobic epoxy-based polypropylene macroreticular resins)-based composites (ReA-NF-DAEs) exhibited outstanding relative activities, thermal stabilities, storage stabilities, and processabilities. The ReA-NF-DAEs were able to be reused to catalyze the conversion from D-fructose to D-allulose, and kept more than 60% of their activities after eight cycles.


Assuntos
Estabilidade Enzimática , Enzimas Imobilizadas , Enzimas Imobilizadas/química , Carboidratos Epimerases/química , Carboidratos Epimerases/metabolismo , Nanoestruturas/química , Frutose/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
2.
Anticancer Drugs ; 34(7): 852-856, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36729892

RESUMO

The optimal pharmaceutical regimen for advanced thymic epithelial tumors (TETs) remains controversial when first-line chemotherapy fails. This retrospective study aims to evaluate the efficacy and safety of anlotinib treatment for patients with relapsed and refractory TETs. Patients with progressive disease after failure of platinum-based chemotherapy were enrolled in this study. Anlotinib was orally taken once a day at an initial dose of 12 mg (10 mg when body weight <60 kg). The cycle was repeated every 3 weeks (2 weeks of treatment followed by 1-week rest). Objective response rate (ORR) and progression-free survival (PFS) were recorded as primary endpoints. There were 50 patients enrolled in this study from October 2018 to June 2021 at a median age of 50 (range 23-79) years old. Patients with thymoma and thymic carcinoma were 33 (66%) and 17 (34%), respectively. The ORR in thymoma and thymic carcinoma patients were 33% (11/33) and 41% (7/17), respectively. The median PFS (mPFS) was 7 (95% CI, 5.9-10.2) months in thymoma patients and 6 (95% CI, 4.6-9.3) months in the thymic carcinoma group. Eleven patients experienced dose reduction due to toxicities, among whom, eight patients discontinued treatment even after dose reduction. Six patients with thymoma showed myasthenia gravis deterioration during treatment, and two of them died of myasthenia gravis crisis. Anlotinib is active in patients with advanced TETs refractory to routine chemotherapy. Prescription of anlotinib to patients with myasthenia gravis should be made cautiously.


Assuntos
Miastenia Gravis , Neoplasias Epiteliais e Glandulares , Timoma , Neoplasias do Timo , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Timoma/tratamento farmacológico , Timoma/patologia , Estudos Retrospectivos , Neoplasias do Timo/tratamento farmacológico , Neoplasias do Timo/patologia , Neoplasias Epiteliais e Glandulares/tratamento farmacológico
3.
Plant J ; 103(4): 1575-1589, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32433816

RESUMO

Arabidopsis thaliana AKR2A plays an important role in plant responses to cold stress. However, its exact function in plant resistance to cold stress remains unclear. In the present study, we found that the contents of very long-chain fatty acids (VLCFAs) in akr2a mutants were decreased, and the expression level of KCS1 was also reduced. Overexpression of KCS1 in the akr2a mutants could enhance VLCFAs contents and chilling tolerance. Yeast-2-hybrid and bimolecular fluorescence complementation (BIFC) results showed that the transmembrane motif of KCS1 interacts with the PEST motif of AKR2A both in vitro and in vivo. Overexpression of KCS1 in akr2a mutants rescued akr2a mutant phenotypes, including chilling sensitivity and a decrease of VLCFAs contents. Moreover, the transgenic plants co-overexpressing AKR2A and KCS1 exhibited a greater chilling tolerance than the plants overexpressing AKR2A or KCS1 alone, as well as the wild-type. AKR2A knockdown and kcs1 knockout mutants showed the worst performance under chilling conditions. These results indicate that AKR2A is involved in chilling tolerance via an interaction with KCS1 to affect VLCFA biosynthesis in Arabidopsis.


Assuntos
Acetiltransferases/fisiologia , Proteínas de Arabidopsis/fisiologia , Ácidos Graxos/metabolismo , Chaperonas Moleculares/fisiologia , Acetiltransferases/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Temperatura Baixa/efeitos adversos , Resposta ao Choque Frio , Ácidos Graxos/fisiologia , Regulação da Expressão Gênica de Plantas , Técnicas de Silenciamento de Genes , Chaperonas Moleculares/genética , Fotossíntese , Plantas Geneticamente Modificadas , Técnicas do Sistema de Duplo-Híbrido
4.
Catheter Cardiovasc Interv ; 97 Suppl 2: 1072-1079, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33764682

RESUMO

OBJECTIVES: To investigate a strategy for ultra-low volume contrast percutaneous coronary intervention (PCI) with the aims of preserving renal function and observing the 90-day clinical endpoint in patients with non-ST-elevated myocardial infarction (non-STEMI) and chronic kidney disease (CKD). BACKGROUND: The feasibility, safety, and clinical utility of PCI with ultra-low radio-contrast medium in patients with non-STEMI and CKD are unknown. METHODS: A total of 29 patients with non-STEMI and CKD (estimated glomerular filtration rate [eGFR] of ≤60 ml/min/1.73 m2 ) were included. Ultra-low volume contrast PCI was performed after minimal contrast coronary angiography using zero contrast optical coherence tomography (OCT) guidance. Pre- and post-PCI angiographic measurements were performed using quantitative flow ratio (QFR) for pre-perfusion assessment and verifying improvement. RESULTS: The median creatinine level was 2.1 (inter-quartile range 1.8-3.3), and mean eGFR was 48 ± 8 ml/min/1.73 m2 pre-PCI. During the PCI procedure, OCT revealed 15 (52%) cases of abnormalities post-dilation. There was no significant change in the creatinine level and eGFR in the short- or long-term, and no major adverse events were observed. CONCLUSION: In non-STEMI patients with high-risk CKD who require revascularization, QFR and no contrast OCT-guided ultra-low contrast PCI may be performed safely without major adverse events.


Assuntos
Infarto do Miocárdio sem Supradesnível do Segmento ST , Intervenção Coronária Percutânea , Insuficiência Renal Crônica , Angiografia Coronária , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/diagnóstico , Tomografia de Coerência Óptica , Resultado do Tratamento
5.
Appl Microbiol Biotechnol ; 105(16-17): 6369-6379, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34402939

RESUMO

Monascus yellow pigments (MYPs), as food colorants, are of great interest to the food industry, because of their beneficial biological activities. In this study, a comparative metabolomics strategy revealed the metabolic regulatory mechanism of MYP overproduction, comparing ammonium chloride with peptone as nitrogen sources. Metabolomics-based multivariate regression modeling showed that metabolic biomarkers/modules, such as glucose, lactate, and the pentose phosphate (PP) pathway, were closely associated with the biosynthesis of MYPs. Exogenous addition of glucose increased production of MYPs, whereas lactate reduced it. Inhibition of the PP pathway with dehydroepiandrosterone decreased MYP production, while increasing the shunting production of orange and red pigments. All these treatments significantly changed the expression profiles of the pigment biosynthetic gene cluster and the mycelial morphology. Overall, this study demonstrates the feasibility of elucidating the mechanism of MYP biosynthesis by comprehensive metabolomics analysis, as well as discovering potential engineering targets of efficiency improvements to commercial MYP production. KEY POINTS: • Comparative metabolomics revealed the biomarkers/modules of MYP production. • A rational exogenously adding strategy was implemented to regulate MYP synthesis. • Expression profiles of gene cluster and mycelial morphology were characterized.


Assuntos
Monascus , Cloreto de Amônio , Metabolômica , Nitrogênio , Pigmentos Biológicos
6.
Parasitol Res ; 120(4): 1209-1217, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33559752

RESUMO

Common bed bugs (Cimex lectularius L.) are hematophagous pests present in urban environments across the globe. It is widely established that they have a strong host preference for humans. However, there are records of C. lectularius feeding upon a range of mammalian and avian hosts, including rodents, in the field. There is little information available about how frequently common bed bugs feed on alternative hosts in residential settings, but understanding this phenomenon has implications for both management of infestations and public health. Here, we examined cohorts of C. lectularius collected from 13 different dwellings in the state of New Jersey, USA, that were known to be simultaneously infested with house mice (Mus musculus domesticus). Host-specific quantitative polymerase chain reaction (qPCR) was used to determine if blood meals were taken from mice, while 16S rRNA gene amplicon sequencing was used to screen the bed bugs for the presence of zoonotic bacterial pathogens. We found no evidence that any of the bed bugs we collected fed on mice. Furthermore, the insects harbored depauperate bacterial communities that did not include known human pathogens. However, host-specific qPCR detected feline DNA in a pool of bed bugs from one dwelling, suggesting that interaction with domestic pets should be further investigated. Although sampling in this study was limited, the approach described herein will be useful for additional studies of the interactions between bed bugs and alternative blood meal hosts.


Assuntos
Bactérias/isolamento & purificação , Percevejos-de-Cama/microbiologia , Sangue/microbiologia , Animais , Bactérias/genética , Gatos , DNA/sangue , Feminino , Especificidade de Hospedeiro , Humanos , Masculino , Camundongos , RNA Bacteriano/genética , RNA Ribossômico 16S/genética
7.
J Cell Physiol ; 234(7): 11440-11450, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30548582

RESUMO

microRNAs (miRs) are essential in the development of heart failure. The aim of this study is to investigate the effect of microRNA-330 (miR-330) on left ventricular remodeling via the TGF-ß1/Smad3 signaling pathway by targeting the sex-determining region Y (SRY) in mice with myocardial ischemia-reperfusion injury (MIRI). Differentially expressed gene (DEG) in myocardial ischemia-reperfusion (IR) was screened out and the miR that targeted the DEG was also predicted and verified. A model of MIRI was established to detect the expression of miR-330, SRY, transforming growth factor-ß (TGF-ß1), and Sekelsky mothers against dpp3 (Smad3). To further investigate the role of miR-330 in MIRI with the involvement of SRY and TGF-ß1/Smad3 signaling pathway, the modeled mice were treated with different mimic, inhibitor, or small interfering RNA (siRNA) to observe the changes of the related gene expression, as well as the myocardial infarction size and volume of myocardial collagen. SRY was screened out and verified as a target gene of miR-330. The MIRI mice showed enlarged myocardial infarction size, increased volume of myocardial collagen, increased expression of miR-330, TGF-ß1 and Smad3, while decreased the expression of SRY. The MIRI mice treated with miR-330 inhibitor showed decreased myocardial infarction size, the volume of myocardial collagen, and expression of TGF-ß1 and Smad3 but promoted expression of SRY. Our findings demonstrated that downregulated miR-330 could suppress left ventricular remodeling to inhibit the activation of the TGF-ß1/Smad3 signaling pathway via negatively targeting of SRY in mice with MIRI. This can be a potential target in the strategy to attenuate patient suffering.


Assuntos
MicroRNAs/metabolismo , Isquemia Miocárdica/patologia , Proteína da Região Y Determinante do Sexo/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Remodelação Ventricular , Animais , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Isquemia Miocárdica/metabolismo , Distribuição Aleatória , Traumatismo por Reperfusão , Proteína da Região Y Determinante do Sexo/genética , Proteína Smad3/genética , Fator de Crescimento Transformador beta1/genética
8.
Biotechnol Lett ; 41(10): 1213-1222, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31451996

RESUMO

OBJECTIVES: In order to elucidate the antibacterial activity and mechanism of S. alboflavus TD-1 active metabolites, the minimal inhibitory concentration of R. solanacearum and other effects on cell wall, cell membrane, nucleic acid, protein and cell morphology were studied. Besides, based on LCMS-IT-TOF, the active metabolites of S. alboflavus TD-1 were preliminarily analyzed. RESULTS: In this study, We found that the active metabolites had obvious inhibitory effect on R. solanacearum, and the minimal inhibitory concentration (MIC) of R. solanacearum was 3.125 mg/mL. And the treatment of 10 mg/mL active metabolites can increase the permeability of R. solanacearum membranes, destroy the cell wall integrity, inhibit the synthesis of bacterial nucleic acids and proteins, and cause leakage of bacterial nucleic acids and proteins, obstruct the normal expression of proteins and destroy their bacterial morphology. At the same time, We speculated the molecular weights corresponding to the six compounds were 618, 615, 615, 615, 646, 646, respectively among the active metabolites, and it was found that were highly unstable. CONCLUSIONS: The active metabolites produced by S. alboflavus TD-1 liquid fermentation contain components that can significant inhibitory effects on R. solanacearum. It had the potential to develop biocontrol agents against bacterial wilt and be a kind potential sources for the preparation of functional anti-pathogenic microbial agents.


Assuntos
Antibacterianos/metabolismo , Antibacterianos/farmacologia , Ralstonia solanacearum/efeitos dos fármacos , Ralstonia solanacearum/crescimento & desenvolvimento , Streptomyces/metabolismo , Antibacterianos/química , Antibacterianos/isolamento & purificação , Vias Biossintéticas/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Meios de Cultura/química , DNA Bacteriano/biossíntese , Fermentação , Testes de Sensibilidade Microbiana , Peso Molecular , Biossíntese de Proteínas/efeitos dos fármacos , Ralstonia solanacearum/citologia
9.
Biochem Biophys Res Commun ; 503(2): 621-624, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-29906463

RESUMO

The fatty acid profile of plant oils determines their quality and uses. Saturated fatty acids are often not desirable from the standpoints of nutrition and some industrial applications. Camelina sativa is a re-emerged oilseed crop, however its oil needs to be improved to meet different application requirements. In this study, saturated fatty acids were greatly reduced by down-regulating genes encoding the fatty acyl-ACP thioesterases (FATB). An artificial microRNA (amiFATB) was created by replacing a microRNA sequence in the camelina Csa-miR159a gene with a FATB gene specific sequence. Seed-specific expression of amiFATB caused a 45% reduction of palmitic acid (16:0) and a 38% reduction of stearic acid (18:0) compared to wildtype seeds. The total saturated fatty acid content was decreased by 35% from 14.6% to 9.4% of total fatty acids. When amiFATB was expressed in a high-oleic acid transgenic line, it caused further increased oleic acid content. This work demonstrates that the FATB genes in camelina can be effectively knocked down by an artificial microRNA targeting gene-specific sequences, thus provides an additional tool to improve seed oils for desired properties.


Assuntos
Camellia/genética , Ácidos Graxos/genética , Regulação da Expressão Gênica de Plantas , Técnicas de Silenciamento de Genes , Proteínas de Plantas/genética , Sementes/genética , Tioléster Hidrolases/genética , Camellia/química , Regulação para Baixo , Ácidos Graxos/análise , Genes de Plantas , MicroRNAs/genética , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Sementes/química
10.
Pak J Pharm Sci ; 31(6): 2487-2495, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30473522

RESUMO

We investigated the cellulase-assisted extraction and anti-ultraviolet activity of water-soluble polysaccharides from the root of Flammulina velutipes on Caenorhabditis elegans. A Box-Behnken design experiment with three factors and three levels, including enzymolysis temperature, microwave time, and microwave power, was designed on the basis of the results of single-factor experiments. For improving the polysaccharide yield of F. velutipes root, the following optimal extraction conditions were used: 52.67°C enzymolysis temperature, 80s microwave time, and 144 W microwave power. Under optimal conditions, the actual measured value of the yield was 2.01% (w/w) and the predicted value was 2.06% (w/w). One fraction (FRP-2) was isolated and purified, and its characteristics were analyzed. The average mean molecular weight of FRP-2 was measured to be 2.60×105 Da, and its monosaccharide composition is mainly glucose. The sugar units are present both in the α-configuration and ß-configuration. Moreover, FRP-2 exhibited certain anti-ultraviolet activity to C. elegans when the polysaccharide concentration ranged between 0.05mg/mL and 0.20mg/mL.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/efeitos da radiação , Celulase/química , Flammulina , Extratos Vegetais/farmacologia , Raízes de Plantas , Polissacarídeos/farmacologia , Protetores contra Radiação/farmacologia , Raios Ultravioleta , Animais , Configuração de Carboidratos , Flammulina/química , Hidrólise , Micro-Ondas , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Protetores contra Radiação/química , Protetores contra Radiação/isolamento & purificação , Relação Estrutura-Atividade , Temperatura , Fatores de Tempo
11.
Molecules ; 22(3)2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28257052

RESUMO

The effect of light on Monascus and the underlying mechanism have received a great deal of interest for the industrial application of Monascus pigments. In this study, we have examined the effects of blue light on the culture morphology, mycelium growth, pigments, and citrinin yield of Monascus in liquid-state and oscillation fermentation, and explored the mechanism at a physiological level. It was found that blue light affected the colony morphology, the composition (chitin content), and permeability of the Monascus mycelium cell wall in static liquid culture, which indicates blue light benefits pigments secreting from aerial mycelium to culture medium. In liquid oscillation fermentation, the yields of Monascus pigments in fermentation broth (darkness 1741 U/g, blue light 2206 U/g) and mycelium (darkness 2442 U/g, blue light 1900 U/g) cultured under blue light and darkness are different. The total pigments produced per gram of Monascus mycelium under blue light was also higher (4663 U/g) than that in darkness (4352 U/g). However, the production of citrinin (88 µg/g) under blue light was evidently lower than that in darkness (150 µg/g). According to the degradation of citrinin caused by blue light and hydrogen peroxide, it can be concluded that blue light could degrade citrinin and inhibit the catalase activity of Monascus mycelium, subsequently suppressing the decomposition of hydrogen peroxide, which is the active species that degrades citrinin.


Assuntos
Fermentação , Luz , Monascus/metabolismo , Monascus/efeitos da radiação , Cromatografia Líquida de Alta Pressão , Citrinina/biossíntese , Meios de Cultura , Glucosamina/química , Peróxido de Hidrogênio , Monascus/crescimento & desenvolvimento , Micélio/metabolismo , Fenótipo , Pigmentos Biológicos/biossíntese
12.
Food Technol Biotechnol ; 55(1): 40-47, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28559732

RESUMO

In this study, the effects of temperature-shift (from 30 to 25 °C) and temperature-constant (at 30 °C) cultivation on the mass of Monascus fuliginosus CG-6 mycelia and concentration of the produced monacolin K (MK) were monitored. The expression levels of the MK biosynthetic genes of M. fuliginosus CG-6 at constant and variable culture temperatures were analysed by real-time quantitative polymerase chain reaction (RT-qPCR). The total protein was collected and determined by liquid chromatography-electrospray ionisation with tandem mass spectrometry (LC-ESI-MS/MS). Results showed that the maximum mycelial mass in temperature-shift cultivation was only 0.477 g of dry cell mass per dish, which was lower than that in temperature-constant cultivation (0.581 g of dry cell mass per dish); however, the maximum concentration of MK in temperature-shift cultivation (34.5 µg/mL) was 16 times higher than that in temperature-constant cultivation at 30 °C (2.11 µg/mL). Gene expression analysis showed that the expression of the MK biosynthetic gene cluster at culture temperature of 25 °C was higher than that at 30 °C, which was similar to the trend of the MK concentration, except for individual MK B and MK C genes. Analysis of differential protein expression revealed that 2016 proteins were detected by LC-ESI-MS/MS. The expression level of efflux pump protein coded by the MK I gene exhibited the same upregulated trend as the expression of MK I in temperature-shift cultivation. Temperature-shift cultivation enhanced the expression of proteins in the secondary metabolite production pathway, but suppressed the expression of proteins involved in the mycelial growth.

13.
Mol Phylogenet Evol ; 94(Pt B): 778-790, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26541239

RESUMO

Termites of the genus Reticulitermes are ecologically and economically important wood-feeding social insects that are widespread in the Holarctic region. Despite their importance, no study has yet attempted to reconstruct a global time-scaled phylogeny of Reticulitermes termites. In this study, we sequenced mitochondrial (2096bp) and nuclear (829bp) loci from 61 Reticulitermes specimens, collected across the genus' entire range, and one specimen of Coptotermes formosanus, which served as an outgroup. Bayesian and Maximum likelihood analyses conducted on the mitochondrial and nuclear sequences support the existence of four main lineages that span four global geographical regions: North America (NA lineage), western Europe (WE lineage), a region including eastern Europe and western Asia (EA+WA lineage), and eastern Asia (EA lineage). The mitochondrial data allowed us to clarify the phylogenetic relationships among these lineages. They were also used to infer a chronogram that was time scaled based on age estimates for termite fossils (including the oldest Reticulitermes fossils, which date back to the late Eocene-early Oligocene). Our results support the hypothesis that the extant Reticulitermes lineage first differentiated in North America. The first divergence event in the ancestral lineage of Reticulitermes occurred in the early Miocene and separated the Nearctic lineages (i.e., the NA lineages) from the Palearctic lineages (i.e., WE, EE+WA, and EA lineages). Our analyses revealed that the main lineages of Reticulitermes diversified because of vicariance and migration events, which were probably induced by major paleogeographic and paleoclimatic changes that occurred during the Cenozoic era. This is the first global and comprehensive phylogenetic study of Reticulitermes termites, and it provides a crucial foundation for studying the evolution of phenotypic and life-history traits in Reticulitermes. For instance, the phylogeny we obtained suggested that 'asexual queen succession', a unique reproductive system, independently evolved at least three times during the diversification of the genus.


Assuntos
Isópteros/classificação , Animais , Evolução Biológica , Núcleo Celular , DNA Mitocondrial , Genes de Insetos , Especiação Genética , Isópteros/genética , Filogenia , Filogeografia
14.
J Econ Entomol ; 109(1): 273-83, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26494709

RESUMO

Insecticide sprays and dusts are used for controlling bed bugs, Cimex lectularius L. In natural environments, bed bugs have daily access to hosts after they are exposed to insecticides. The established laboratory insecticide bioassay protocols do not provide feeding after insecticide treatments, which can result in inflated mortality compared with what would be encountered in the field. We evaluated the effect of posttreatment feeding on mortality of bed bugs treated with different insecticides. None of the insecticides tested had a significant effect on the amount of blood consumed and percent feeding. The effect of posttreatment feeding on bed bug mortality varied among different insecticides. Feeding significantly reduced mortality in bed bugs exposed to deltamethrin spray, an essential oil mixture (Bed Bug Fix) spray, and diatomaceous earth dust. Feeding increased the mean survival time for bed bugs treated with chlorfenapyr spray and a spray containing an essential oil mixture (Ecoraider), but did not affect the final mortality. First instars hatched from eggs treated with chlorfenapyr liquid spray had reduced feeding compared with nymphs hatched from nontreated eggs. Those nymphs hatched from eggs treated with chlorfenapyr liquid spray and successfully fed had reduced mortality and a higher mean survival time than those without feeding. We conclude that the availability of a bloodmeal after insecticide exposure has a significant effect on bed bug mortality. Protocols for insecticide efficacy testing should consider offering a bloodmeal to the treated bed bugs within 1 to 3 d after treatment.


Assuntos
Percevejos-de-Cama/efeitos dos fármacos , Inseticidas/farmacologia , Animais , Percevejos-de-Cama/crescimento & desenvolvimento , Percevejos-de-Cama/fisiologia , Comportamento Alimentar/efeitos dos fármacos , Masculino , Ninfa/efeitos dos fármacos , Ninfa/fisiologia
15.
J Econ Entomol ; 109(2): 762-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26637535

RESUMO

Two experiments were conducted to evaluate the effects of various interventions on low-level bed bug, Cimex lectularius L., populations in occupied apartments. The first experiment was conducted in occupied apartments under three intervention conditions: never treated (Group I), recently treated with no further treatment (Group II), and recently treated with continued treatment (Group III). Each apartment was monitored with pitfall-style traps (interceptors) installed at beds and upholstered furniture (sleeping and resting areas) along with ∼18 additional interceptors throughout the apartment. The traps were inspected every 2 wk. After 22 wk, bed bugs had been eliminated (zero trap catch for eight consecutive weeks and none detected in visual inspections) in 96, 87, and 100% of the apartments in Groups I, II, and III, respectively. The second experiment investigated the impact of interceptors as a control measure in apartments with low-level infestations. In the treatment group, interceptors were continuously installed at and away from sleeping and resting areas and were inspected every 2 wk for 16 wk. In the control group, interceptors were placed in a similar fashion as the treatment group but were only placed during 6­8 and 14­16 wk to obtain bed bug counts. Bed bug counts were significantly lower at 8 wk in the treatment group than in the control group. At 16 wk, bed bugs were eliminated in 50% of the apartments in the treatment group. The implications of our results in the development of bed bug management strategies and monitoring protocols are discussed.


Assuntos
Percevejos-de-Cama , Controle de Insetos/métodos , Animais , Habitação
16.
Prep Biochem Biotechnol ; 46(8): 772-779, 2016 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26950801

RESUMO

Microbial fermentation of citrinin-free Monascus pigments is in favor in the development of food industry. This study investigated the influences of carbon source, nitrogen source, and mineral salts on the cell growth, monascin (MS), and citrinin (CT) production in Monascus M9. A culture medium composition was established for maximizing the production of citrinin-free MS in submerged culture, as follows: 50 g/L Japonica rice powder, 20 g/L NH4NO3, 3 g/L NaNO3, 1.5 g/L KH2PO4, 1 g/L MgSO4 · 7H2O, 0.2 g/L MnSO4. Under these conditions, no CT was detectable by high performance liquid chromatography. The yield of MS reached 14.11 mg/g, improving approximately 30% compared with before optimization.


Assuntos
Meios de Cultura/metabolismo , Fermentação , Compostos Heterocíclicos com 3 Anéis/metabolismo , Microbiologia Industrial/métodos , Monascus/metabolismo , Citrinina/metabolismo , Nitratos/metabolismo , Oryza/microbiologia
17.
Biotechnol Lett ; 37(5): 1043-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25564393

RESUMO

Light is an important signal for fungi. We analyzed the influence of blue light of various intensities and illumination times on growth, monascin (MS) and ankaflavin (AK) biosyntheses in Monascus strain M9. Blue light changed the color of colonies. The colonies grown in the dark were orange, but turned pale when exposed to continuous blue light. MS production increased by 12.5, 27, and 14.5 % under blue light of 100 lux for 15 min/day, 100 lux for 30 min/day, and 200 lux for 15 min/day, respectively, compared to growth in the dark. AK production increased by 14.4, 22, and 13 % under the same condition. MS and AK production decreased when exposed to blue light of 300 and 450 lux. The expression of pigment biosynthetic genes were analyzed by real-time quantitative PCR and correlated with phenotypic production of MS and AK.


Assuntos
Flavinas/metabolismo , Compostos Heterocíclicos com 3 Anéis/metabolismo , Luz , Monascus/crescimento & desenvolvimento , Monascus/efeitos da radiação , Vias Biossintéticas/efeitos da radiação , Perfilação da Expressão Gênica , Monascus/metabolismo , Pigmentos Biológicos/metabolismo
18.
J Econ Entomol ; 108(3): 1298-303, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26470258

RESUMO

Effective bed bug (Cimex lectularius L.) monitors have been actively sought in the past few years to help detect bed bugs and measure the effectiveness of treatments. Most of the available active monitors are either expensive or ineffective. We designed a simple and affordable active bed bug monitor that uses sugar-yeast fermentation and an experimental chemical lure to detect bed bugs. The sugar-yeast mixture released carbon dioxide at a similar rate (average 405.1 ml/min) as dry ice (average 397.0 ml/min) during the first 8 h after activation. In naturally infested apartments, the sugar-yeast monitor containing an experimental chemical lure (nonanal, L-lactic acid, 1-octen-3-ol, and spearmint oil) was equally effective as the dry ice monitor containing the same lure in trapping bed bugs. Placing one sugar-yeast monitor per apartment for 1-d was equally effective as 11-d placement of 6-18 Climbup insect interceptors (a commonly used bed bug monitor) under furniture legs for trapping bed bugs. When carbon dioxide was present, pair-wise comparisons showed the experimental lure increased trap catch by 7.2 times. This sugar-yeast monitor with a chemical lure is an affordable and effective tool for monitoring bed bugs. This monitor is especially useful for monitoring bed bugs where a human host is not present.


Assuntos
Percevejos-de-Cama/efeitos dos fármacos , Carboidratos/farmacologia , Gelo-Seco , Controle de Insetos/métodos , Feromônios/farmacologia , Fermento Seco/farmacologia , Animais , Controle de Insetos/economia , Controle de Insetos/instrumentação
19.
J Econ Entomol ; 107(6): 2163-70, 2014 12.
Artigo em Inglês | MEDLINE | ID: mdl-26470082

RESUMO

The bed bug, (Cimex lectularius L.), is a difficult pest to control. Prevalence of insecticide resistance among bed bug populations and concerns over human-insecticide exposure has stimulated the development of alternative bed bug control materials. Many essential oil-based pesticides and detergent insecticides targeting bed bugs have been developed in recent years. We evaluated the efficacy of nine essential oil-based products and two detergents using direct spray and residual contact bioassays in the laboratory. Two conventional insecticides, Temprid SC (imidacloprid and ß-cyfluthrin) and Demand CS (λ-cyhalothrin), were used for comparison. Among the 11 nonsynthetic insecticides tested, only EcoRaider (1% geraniol, 1% cedar extract, and 2% sodium lauryl sulfate) and Bed Bug Patrol (0.003% clove oil, 1% peppermint oil, and 1.3% sodium lauryl sulfate) caused >90% mortality of nymphs in direct spray and forced exposure residual assays. However, the efficacy of EcoRaider and Bed Bug Patrol was significantly lower than that of Temprid SC and Demand CS in choice exposure residual bioassay. Direct spray of EcoRaider caused 87% egg mortality, whereas the other nonsynthetic insecticides had little effect on bed bug eggs. EcoRaider and Bed Bug Patrol did not exhibit detectable repellency against bed bugs in the presence of a carbon dioxide source. These findings suggest that EcoRaider and Bed Bug Patrol are potentially useful pesticides for controlling bed bug infestations, but further testing in naturally infested environments is needed.


Assuntos
Percevejos-de-Cama , Detergentes , Controle de Insetos/métodos , Inseticidas , Óleos Voláteis , Animais , Masculino , Óvulo , Testes de Toxicidade
20.
J Econ Entomol ; 107(6): 2171-81, 2014 12.
Artigo em Inglês | MEDLINE | ID: mdl-26470083

RESUMO

Detection of low-level bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), infestations is essential for early intervention, confirming eradication of infestations, and reducing the spread of bed bugs. Despite the importance of detection, few effective tools and methods exist for detecting low numbers of bed bugs. Scent dogs were developed as a tool for detecting bed bugs in recent years. However, there are no data demonstrating the reliability of trained canines under natural field conditions. We evaluated the accuracy of 11 canine detection teams in naturally infested apartments. All handlers believed their dogs could detect infestations at a very high rate (≥95%). In three separate experiments, the mean (min, max) detection rate was 44 (10-100)% and mean false-positive rate was 15 (0-57)%. The false-positive rate was positively correlated with the detection rate. The probability of a bed bug infestation being detected by trained canines was not associated with the level of bed bug infestations. Four canine detection teams evaluated on multiple days were inconsistent in their ability to detect bed bugs and exhibited significant variance in accuracy of detection between inspections on different days. There was no significant relationship between the team's experience or certification status of teams and the detection rates. These data suggest that more research is needed to understand factors affecting the accuracy of canine teams for bed bug detection in naturally infested apartments.


Assuntos
Percevejos-de-Cama , Cães/psicologia , Habitação , Prática de Saúde Pública/estatística & dados numéricos , Animais , Masculino , Olfato
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