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1.
Opt Express ; 28(1): 665-675, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-32118989

RESUMO

We investigated the effect of coupled quantum wells to reduce electron overflow in InGaN/GaN dot-in-a-wire phosphor-free white color light-emitting diodes (white LEDs) and to improve the device performance. The light output power and external quantum efficiency (EQE) of the white LEDs with coupled quantum wells were increased and indicated that the efficiency droop was reduced. The improved output power and EQE of LEDs with the coupled quantum wells were attributed to the significant reduction of electron overflow primarily responsible for efficiency degradation through the near-surface GaN region. Compared to the commonly used AlGaN electron blocking layer between the device active region and p-GaN, the incorporation of a suitable InGaN quantum well between the n-GaN and the active region does not adversely affect the hole injection process. Moreover, the electron transport to the device active region can be further controlled by optimizing the thickness and bandgap energy of this InGaN quantum well. In addition, a blue-emitting InGaN quantum well is incorporated between the quantum dot active region and the p-GaN, wherein electrons escaping from the device active region can recombine with holes and contribute to white-light emission. The resulting device exhibits high internal quantum efficiency of 58.5% with highly stable emission characteristics and virtually no efficiency droop.

2.
Lancet ; 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32171078

RESUMO

BACKGROUND: Artemisinin and partner-drug resistance in Plasmodium falciparum are major threats to malaria control and elimination. Triple artemisinin-based combination therapies (TACTs), which combine existing co-formulated ACTs with a second partner drug that is slowly eliminated, might provide effective treatment and delay emergence of antimalarial drug resistance. METHODS: In this multicentre, open-label, randomised trial, we recruited patients with uncomplicated P falciparum malaria at 18 hospitals and health clinics in eight countries. Eligible patients were aged 2-65 years, with acute, uncomplicated P falciparum malaria alone or mixed with non-falciparum species, and a temperature of 37·5°C or higher, or a history of fever in the past 24 h. Patients were randomly assigned (1:1) to one of two treatments using block randomisation, depending on their location: in Thailand, Cambodia, Vietnam, and Myanmar patients were assigned to either dihydroartemisinin-piperaquine or dihydroartemisinin-piperaquine plus mefloquine; at three sites in Cambodia they were assigned to either artesunate-mefloquine or dihydroartemisinin-piperaquine plus mefloquine; and in Laos, Myanmar, Bangladesh, India, and the Democratic Republic of the Congo they were assigned to either artemether-lumefantrine or artemether-lumefantrine plus amodiaquine. All drugs were administered orally and doses varied by drug combination and site. Patients were followed-up weekly for 42 days. The primary endpoint was efficacy, defined by 42-day PCR-corrected adequate clinical and parasitological response. Primary analysis was by intention to treat. A detailed assessment of safety and tolerability of the study drugs was done in all patients randomly assigned to treatment. This study is registered at ClinicalTrials.gov, NCT02453308, and is complete. FINDINGS: Between Aug 7, 2015, and Feb 8, 2018, 1100 patients were given either dihydroartemisinin-piperaquine (183 [17%]), dihydroartemisinin-piperaquine plus mefloquine (269 [25%]), artesunate-mefloquine (73 [7%]), artemether-lumefantrine (289 [26%]), or artemether-lumefantrine plus amodiaquine (286 [26%]). The median age was 23 years (IQR 13 to 34) and 854 (78%) of 1100 patients were male. In Cambodia, Thailand, and Vietnam the 42-day PCR-corrected efficacy after dihydroartemisinin-piperaquine plus mefloquine was 98% (149 of 152; 95% CI 94 to 100) and after dihydroartemisinin-piperaquine was 48% (67 of 141; 95% CI 39 to 56; risk difference 51%, 95% CI 42 to 59; p<0·0001). Efficacy of dihydroartemisinin-piperaquine plus mefloquine in the three sites in Myanmar was 91% (42 of 46; 95% CI 79 to 98) versus 100% (42 of 42; 95% CI 92 to 100) after dihydroartemisinin-piperaquine (risk difference 9%, 95% CI 1 to 17; p=0·12). The 42-day PCR corrected efficacy of dihydroartemisinin-piperaquine plus mefloquine (96% [68 of 71; 95% CI 88 to 99]) was non-inferior to that of artesunate-mefloquine (95% [69 of 73; 95% CI 87 to 99]) in three sites in Cambodia (risk difference 1%; 95% CI -6 to 8; p=1·00). The overall 42-day PCR-corrected efficacy of artemether-lumefantrine plus amodiaquine (98% [281 of 286; 95% CI 97 to 99]) was similar to that of artemether-lumefantrine (97% [279 of 289; 95% CI 94 to 98]; risk difference 2%, 95% CI -1 to 4; p=0·30). Both TACTs were well tolerated, although early vomiting (within 1 h) was more frequent after dihydroartemisinin-piperaquine plus mefloquine (30 [3·8%] of 794) than after dihydroartemisinin-piperaquine (eight [1·5%] of 543; p=0·012). Vomiting after artemether-lumefantrine plus amodiaquine (22 [1·3%] of 1703) and artemether-lumefantrine (11 [0·6%] of 1721) was infrequent. Adding amodiaquine to artemether-lumefantrine extended the electrocardiogram corrected QT interval (mean increase at 52 h compared with baseline of 8·8 ms [SD 18·6] vs 0·9 ms [16·1]; p<0·01) but adding mefloquine to dihydroartemisinin-piperaquine did not (mean increase of 22·1 ms [SD 19·2] for dihydroartemisinin-piperaquine vs 20·8 ms [SD 17·8] for dihydroartemisinin-piperaquine plus mefloquine; p=0·50). INTERPRETATION: Dihydroartemisinin-piperaquine plus mefloquine and artemether-lumefantrine plus amodiaquine TACTs are efficacious, well tolerated, and safe treatments of uncomplicated P falciparum malaria, including in areas with artemisinin and ACT partner-drug resistance. FUNDING: UK Department for International Development, Wellcome Trust, Bill & Melinda Gates Foundation, UK Medical Research Council, and US National Institutes of Health.

3.
Cardiol Young ; : 1-2, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32216854

RESUMO

We report a case of an isolated congenital right ventricular outpouching detected incidentally on foetal echocardiogram that was performed due to suspicion of CHD. Subsequent echocardiogram after birth revealed an aneurysm with features of a pseudoaneurysm having a thin and hypokinetic wall connected to the ventricle's cavity via a narrow neck. This pseudoaneurysm appears to be stable in size and of no clinical significance during the short-term follow-up.

4.
Sci Total Environ ; 721: 137612, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32169637

RESUMO

River water quality assessment is one of the most important tasks to enhance water resources management plans. A water quality index (WQI) considers several water quality variables simultaneously. Traditionally WQI calculations consume time and are often fraught with errors during derivations of sub-indices. In this study, 4 standalone (random forest (RF), M5P, random tree (RT), and reduced error pruning tree (REPT)) and 12 hybrid data-mining algorithms (combinations of standalones with bagging (BA), CV parameter selection (CVPS) and randomizable filtered classification (RFC)) were used to create Iran WQI (IRWQIsc) predictions. Six years (2012 to 2018) of monthly data from two water quality monitoring stations within the Talar catchment were compiled. Using Pearson correlation coefficients, 10 different input combinations were constructed. The data were divided into two groups (ratio 70:30) for model building (training dataset) and model validation (testing dataset) using a 10-fold cross-validation technique. The models were evaluated using several statistical and visual evaluation metrics. Result show that fecal coliform (FC) and total solids (TS) had the greatest and least effect on the prediction of IRWQIsc. The best input combinations varied among the algorithms; generally variables with very low correlations displayed weaker performance. Hybrid algorithms improved the prediction power of several of the standalone models, but not all. Hybrid BA-RT outperformed the other models (R2 = 0.941, RMSE = 2.71, MAE = 1.87, NSE = 0.941, PBIAS = 0.500). PBIAS indicated that all algorithms, with the exceptions of RT, BA-RT and CVPS-REPT, overestimated WQI values.

5.
BMJ Open ; 10(3): e035173, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32209632

RESUMO

OBJECTIVES: To understand, describe and analyse the experiences of women with breast cancer in Vietnam when accessing and using breast cancer services. DESIGN: Descriptive qualitative study. Women were interviewed about their experiences from the first time they became aware of symptoms or changes to their body through treatment and post-treatment. This study is the first descriptive study on breast cancer in Vietnam from the perspective of women with a breast cancer diagnosis. PARTICIPANTS: Women (n=13) who had completed or were still receiving treatment for breast cancer, purposively recruited from the north and south of Vietnam. RESULTS: An analysis of the experiences of women with breast cancer in Vietnam revealed a lack of awareness and knowledge about breast cancer and symptoms. Family and social support were described as key factors influencing whether a woman accesses and uses breast cancer services. Cost of treatment and out-of-pocket expenditures limited access to services and resulted in significant financial challenges for women and their families. CONCLUSIONS: Vietnam has made huge strides in improving cancer care, and is tackling a complex and expanding public health challenge, however, there are a number of areas requiring strengthening and future research. While Vietnam has successfully expanded social health insurance coverage, changes that increase the percentage of costs covered for specific treatments, such as chemotherapy or radiotherapy, could benefit women and their families.

6.
Trends Cancer ; 6(2): 98-110, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32061310

RESUMO

TP53 is the most frequently mutated gene in breast cancer, but its role in survival is confounded by different studies concluding that TP53 mutations are associated with negative, neutral, or positive outcomes. Closer examination showed that many studies were limited by factors such as imprecise methods to detect TP53 mutations and small cohorts that combined patients treated with drugs having very different mechanisms of action. When only studies of patients receiving the same treatment(s) were compared, they tended to agree. These analyses reveal a role for TP53 in response to different treatments as complex as its different biological activities. We discuss studies that have assessed the role of TP53 mutations in breast cancer treatment and limitations in interpreting reported results.

7.
Tob Control ; 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32041832

RESUMO

BACKGROUND: One of the most significant barriers to tax reform and tax rate increases in Vietnam is the threat of illicit trade promulgated by the tobacco industry. The industry argues that higher taxes will stimulate smuggling, thereby undermining tax policy objectives and impairing the domestic tobacco manufacturing. Unfortunately, there is a dearth of updated and independent studies to verify this claim and inform the tax reform in the country. OBJECTIVES: The present paper attempts to generate new estimates of the illicit consumption and compare them to a prior study to ascertain the changes in the levels of the illicit trade after a tobacco excise tax increase. METHODS: The study uses primary data collected from the Tobacco Consumption Survey in late 2017. It is a multistage cluster random household survey, covering a sample size of over 2700 smokers, and purposively designed to make its results comparable to prior estimates, which have been done before the tax increase. Particularly, we collect packs from selected smokers and perform careful inspection to identify the prevalence of illicit products. In addition to the consumption, we collect data on brand choices, cigarette prices, the types of stores that the smokers bought their cigarettes, as well as their socioeconomic characteristics. They allow us to determine the regional variation of the illicit trade, identify the main illicit cigarette brands, compare the prices of the licit and illicit cigarettes, and examine the main sources of the illicit cigarettes. Incomes of the licit and illicit cigarette smokers are also compared. RESULTS: Contrary to the tobacco industry's predictions, our estimates demonstrate that the level of the illicit trade declined even after the increase of taxes imposed on tobacco products in Vietnam. The illicit cigarettes account for only about 13.72% of the total cigarette consumption in Vietnam in 2017, lower than the 20.7% estimate in 2012 done by the previous study. The illicit cigarettes are heavily concentrated in the southern provinces of Vietnam bordering Cambodia, and locally accessible to the smokers from grocery stores. Jet and Hero are the two most popular brands, representing over 80% of total illicit consumption in the country. Interestingly, the illicit cigarettes are on average more expensive than the illicit products in Vietnam, unlike many other countries where the former are typically cheaper than the latter. Consequently, as is to be expected, the illicit cigarette smokers tend to earn higher incomes than those smoking the licit products. CONCLUSIONS: Raising the taxes levied on tobacco does not necessarily cause higher illicit consumption in Vietnam as widely stated by the tobacco industry. The Government of Vietnam should recognise the tobacco tax policy as the most effective and cost-effective tobacco control measure and establish a clear road map of progressive tobacco excise tax increases so that total tax levied on tobacco accounts for at least 75% of retail price as suggested by the WHO to reduce smoking prevalence in the country.

8.
Sci Rep ; 10(1): 2547, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32054926

RESUMO

We report the demonstration of the first axial AlInN ultraviolet core-shell nanowire light-emitting diodes with highly stable emission in the ultraviolet wavelength range. During epitaxial growth of the AlInN layer, an AlInN shell is spontaneously formed, resulting in reduced nonradiative recombination on the nanowire surface. The AlInN nanowires exhibit a high internal quantum efficiency of ~52% at room temperature for emission at 295 nm. The peak emission wavelength can be varied from 290 nm to 355 nm by changing the growth conditions. Moreover, significantly strong transverse magnetic (TM) polarized emission is recorded, which is ~4 times stronger than the transverse electric (TE) polarized light at 295 nm. This study provides an alternative approach for the fabrication of new types of high-performance ultraviolet light emitters.

10.
Proc Natl Acad Sci U S A ; 117(7): 3440-3445, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32005710

RESUMO

Although some important advances in the modeling of sorption and hygrothermal deformations of nanoporous materials such as hydrated cement paste, shale, coal, and some other rocks and soils have already been made, a comprehensive nanoporomechanics theory remains elusive. Here we strive to formulate it based on Gibb's free energy of the solid-fluid system and on the recently derived Nguyen-Rahimi-Bazant (NRB) isotherm, which corrects the Brunauer-Emmett-Teller (BET) isotherm for the effect of hindered adsorbed water in filled nanopores and extends through the capillary range up to saturation. The challenge is to capture all of the basic types of relevant published experimental data, including 1) a complete sorption isotherm of hydrated cement paste (including the capillary range), 2) pore size distribution, 3) autogenous shrinkage, 4) drying shrinkage and swelling, 5) water loss or humidity change due to heating, 6) thermal expansion at various humidities, and 7) water loss of specimens caused by compression. The previous models can fit only a few data types. The present model fits all of them. It is ready for computer simulations needed to minimize the deleterious moisture effects on long-time deformations, cracking damage, and fracture in concrete infrastructure and thereby to reduce indirectly the enormous carbon footprint of concrete. Adaptations to shale, coal beds, etc., are possible.

11.
Sci Total Environ ; 715: 136836, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32007881

RESUMO

Groundwater resources constitute the main source of clean fresh water for domestic use and it is essential for food production in the agricultural sector. Groundwater has a vital role for water supply in the Campanian Plain in Italy and hence a future sustainability of the resource is essential for the region. In the current paper novel data mining algorithms including Gaussian Process (GP) were used in a large groundwater quality database to predict nitrate (contaminant) and strontium (potential future increasing) concentrations in groundwater. The results were compared with M5P, random forest (RF) and random tree (RT) algorithms as a benchmark to test the robustness of the modeling process. The dataset includes 246 groundwater quality samples originating from different wells, municipals and agricultural. It was divided for the modeling process into two subgroups by using the 10-fold cross validation technique including 173 samples for model building (training dataset) and 73 samples for model validation (testing dataset). Different water quality variables including T, pH, EC, HCO3-, F-, Cl-, SO42-, Na+, K+, Mg2+, and Ca2+ have been used as an input to the models. At first stage, different input combinations have been constructed based on correlation coefficient and thus the optimal combination was chosen for the modeling phase. Different quantitative criteria alongside with visual comparison approach have been used for evaluating the modeling capability. Results revealed that to obtain reliable results also variables with low correlation should be considered as an input to the models together with those variables showing high correlation coefficients. According to the model evaluation criteria, GP algorithm outperforms all the other models in predicting both nitrate and strontium concentrations followed by RF, M5P and RT, respectively. Result also revealed that model's structure together with the accuracy and structure of the data can have a relevant impact on the model's results.

12.
Artigo em Inglês | MEDLINE | ID: mdl-32101119

RESUMO

BACKGROUND: Heat-labile enterotoxin B subunit (LTB) produced by Escherichia coli, a non-toxic protein subunit with potential biological properties, is a powerful mucosal and parenteral adjuvant which can induce a strong immune response against co-administered antigens. OBJECTIVE: In the present study, we want to produce LTB protein which encoded by the optimized ltb (also known synthetic ltb, s-ltb) gene in centella plant (Centella asiatica) for use as a antigen in next studies. METHODS: The s-ltb gene was cloned into a plant expression vector, pMYO51, adjacent to the CaMV 35S promoter and was then introduced into centella plant by biolistic transformation. PCR amplification was conducted to determine the presence of s-ltb gene in transgenic centella plant. Expression of s-ltb gene was analyzed by immunoblotting and quantified by ELISA. In vitro activity of LTB protein was determined by GM1-ELISA. RESULTS: PCR amplification has found seven transgenic centella individuals. However, only five of them produced LTB protein. ELISA analysis showed that the highest amount of LTB protein detected in transgenic centella leaves was about 0.8% of the total soluble protein. GM1-ELISA assay indicated that plant LTB protein bound specifically to GM1-ganglioside, suggesting that the LTB subunits formed active pentamers. CONCLUSION: The s-ltb gene that was successfully transformated into centella plants by biolistic method has produced a relatively high amount of plant LTB protein in the pentameric quaternary structure that has GM1-ganglioside binding affinity, a receptor on the intestinal epithelial membrane.

13.
ACS Appl Mater Interfaces ; 12(9): 10291-10298, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-31944649

RESUMO

Filter membrane processes are water purification methods that use a partially permeable membrane to separate contaminants from drinking water and wastewater. Although highly effective, they suffer from biofouling due to the aggregation of bacteria and contaminants from the filtrate, thus rendering the membrane unusable. Consequently, the membrane needs to be replaced on a regular basis, which interrupts filtration operation, reduces throughput, and increases production cost. To address this issue, we have developed a new method to remove biofoulants via induction heating on a modified membrane with magnetite (Fe3O4) magnetic nanoparticles (MNPs) coating. Under applied alternating magnetic field (AMF), the surface temperature of the MNPs coating reaches 180 °C with a heating rate of 1.03 °C/s, which disintegrates biofoulants generated by model bacteria (Bacillus subtilis) and by those present in environmental water samples collected from a local lake. The heating process is capable of cleaning biofoulants for several cycles without damaging the filtration function of the membrane. Furthermore, magnetic induction heating on the modified membrane allows uniform high-intensity heat generation on a large surface in only a few minutes using inexpensive MNPs, which can potentially be scaled up for industrial applications.

14.
Nutrients ; 12(1)2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31935866

RESUMO

Clinical applications of ginger with an expectation of clinical benefits are receiving significant attention. This systematic review aims to provide a comprehensive discussion in terms of the clinical effects of ginger in all reported areas. Following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guideline, randomized controlled trials on the effects of ginger were investigated. Accordingly, 109 eligible papers were fully extracted in terms of study design, population characteristics, evaluation systems, adverse effects, and main outcomes. The reporting quality of the included studies was assessed based on the Cochrane Collaboration's tool for assessing the risk of bias in randomized trials and integrated together with studies that investigated the same subjects. The included studies that examined the improvement of nausea and vomiting in pregnancy, inflammation, metabolic syndromes, digestive function, and colorectal cancer's markers were consistently supported, whereas other expected functions were relatively controversial. Nevertheless, only 43 clinical trials (39.4%) met the criterion of having a 'high quality of evidence.' In addition to the quality assessment result, small populations and unstandardized evaluation systems were the observed shortcomings in ginger clinical trials. Further studies with adequate designs are warranted to validate the reported clinical functions of ginger.

15.
Pest Manag Sci ; 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31970888

RESUMO

BACKGROUND: Detection and diagnosis of emerging arthropod outbreaks in horticultural glasshouse crops, such as bok choy and spinach, is both important and challenging. A major challenge is to accurately detect and diagnose arthropod outbreaks in growing crops (changes in canopy size, structure, and composition), and when crops are grown under three fertilization regimes. Day-time remote sensing inside glasshouses is highly sensitive to inconsistent lighting, spectral scattering, and shadows casted by glasshouse structures. To avoid these issues, a unique feature of this study was that hyperspectral remote sensing data were acquired after sunset with an active light source. As part of this study, we describe a comprehensive approach to performance assessment of classification algorithms based on hyperspectral remote sensing data. RESULTS: Based on average hyperspectral remote sensing profiles from individual crop plants, none of the 31 individual spectral bands showed consistent significant response to leafminer infestation and non-significant response to fertilizer regime. Multi-band classification algorithms were subjected to a comprehensive performance assessment to quantify risks of model over-fitting and low repeatability of classification algorithms. The performance assessment of classification algorithms addresses the important 'bias-variance trade-off'. Truly independent validation (training and validation data sets being separated over time) revealed that leafminer infestation could be detected with >99% accuracy in both bok choy and spinach. CONCLUSION: We conclude that detailed hyperspectral profiles (not single spectral bands) can accurately detect and diagnose leafminer infestation over time and across fertilizer regimes. Hyperspectral remote sensing data acquisition at night with an active light source has the potential to enable arthropod infestations in glasshouse-grown crops, such as, bok choy and spinach. In addition, we conclude that effective use and deployment of hyperspectral remote sensing requires thorough performance assessments of classification algorithms, and we propose an analytical performance method to address this important matter. © 2020 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

16.
J Clin Neurosci ; 72: 378-385, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31948884

RESUMO

INTRODUCTION: Spinal laminectomy is a common procedure performed to relieve neural compression in patients suffering from myelopathy or radiculopathy. However, up to 40% of patients suffer from persistent post-operative pain and disability, a condition known as Failed Back Surgery Syndrome (FBSS). Excessive scarring in the surgical bed is implicated as a cause. Hydrogels have been proposed to prevent adhesion formation post-laminectomy; however, their efficacy has not been proven. This study uses Chitogel complexed with the iron chelator Deferiprone (Def) to prevent adhesion formation in a sheep laminectomy model. MATERIAL & METHODS: Fifteen Adult Merino sheep (Ovis Aries, 1-5 yrs old) underwent laminectomy at lumbar levels 1-5 and had hydrated aluminum silicate (kaolin) applied to promote adhesion formation. Subjects were randomised to receive at each laminectomy level no-treatment control, Chitogel, Chitogel with Def at 20 mM or 40 mM or Carboxy-methyl-cellulose and Polyethylene oxide (CMC/PEO) gel. The animals were recovered for 3 months post-surgery, followed by assessment with Magnetic Resonance Imaging (MRI) and histopathology of the spinal tissues for evaluating the presence and extent of adhesions. RESULTS: MRI and Histology assessment indicated that Kaolin induced severe inflammation with adhesion formation. Chitogel with and without 20 mM Def decreased inflammation (p < 0.01) and trended to reduce adhesions (p < 0.1). Chitogel with Def 40 mM was not significantly dis-similar to CMC/PEO and did not reduce inflammation or adhesions compared to no-treatment control. CONCLUSION: Chitogel in combination with Def 20 mM is safe and effective in decreasing the inflammatory process and may possibly reduce post-operative adhesions following laminectomy.

17.
J Econ Entomol ; 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31907550

RESUMO

There is high demand for accurate insect sampling methods to inform integrated pest management strategies. Despite widespread application, existing sampling methods, such as portable aspirating and sweep netting, can result in overrepresentation of prominent pests, underrepresentation of natural enemies, and damage to plants. In this study, we test a novel device for insect sampling via anesthetization. Specifically, we test the effect of CO2 (application pressure and duration of exposure) on Lygus hesperus Knight (Hemiptera: Miridae) anesthetization in the laboratory and on insect community density in a strawberry agroecosystem. Carbon dioxide application proves an effective means of anesthetization compared to negative controls, and an increase in net CO2 exposure results in a decrease in time until L. hesperus anesthetization. Field results indicate the CO2 method collects more parasitoids and thrips than a portable aspirator, and at the 50 PSI application pressure and 15-s exposure, the CO2 method results in a comparable number of pests collected as the research standard, a portable aspirator with 8-s aspiration time. Benefits of the CO2 method include minimal plant damage, highly explicit spatial and temporal data, and scalability.

18.
Chem Res Toxicol ; 33(3): 782-788, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-31997638

RESUMO

Lamina II, also called the substantia gelatinosa (SG) of the medullary dorsal horn (the trigeminal subnucleus caudalis, Vc), is thought to play an essential role in the control of orofacial nociception because it receives the nociceptive signals from primary afferents, including thin myelinated Aδ- and unmyelinated C-fibers. Glycine, the main inhibitory neurotransmitter in the central nervous system, plays an essential role in the transference of nociceptive messages from the periphery to higher brain regions. Bisphenol A (BPA) is reported to alter the morphological and functional characteristics of neuronal cells and to be an effector of a great number of ion channels in the central nervous system. However, the electrophysiological effects of BPA on the glycine receptors of SG neurons in the Vc have not been well studied. Therefore, in this study, we used the whole-cell patch-clamp technique to determine the effect of BPA on the glycine response in SG neurons of the Vc in male mice. We demonstrated that in early neonatal mice (0-3 postnatal day mice), BPA did not affect the glycine-induced inward current. However, in the juvenile and adult groups, BPA enhanced the glycine-mediated responses. Heteromeric glycine receptors were involved in the modulation by BPA. The interaction between BPA and glycine appears to have a significant role in regulating transmission in the nociceptive pathway.

19.
mSphere ; 5(1)2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31915233

RESUMO

Carbapenemases confer resistance to nearly all ß-lactam antibiotics. The extensive spread of carbapenemase-producing multidrug-resistant bacteria contributes significantly to hospital-acquired infections. We have developed a novel protein-based binding assay that identifies KPC ß-lactamases from clinical isolates. We used the protein-protein interaction between KPCs and a soluble ß-lactamase inhibitory protein (BLIP) variant, BLIPK74T/W112D, which specifically inhibits KPCs but not other ß-lactamases. In this assay, BLIPK74T/W112D was allowed to form complexes with KPC-2 in bacterial cell lysates and then extracted using His tag binding resins. We demonstrated the presence of KPC-2 by monitoring the hydrolysis of a colorimetric ß-lactam substrate. Also, to further increase the accuracy of the method, a BLIPK74T/W112D-mediated inhibition assay was developed. The binding and inhibition assays were validated by testing 127 Klebsiella pneumoniae clinical isolates with known genome sequences for the presence of KPC. Our assays identified a total of 32 strains as KPC-2 producers, a result in 100% concordance with genome sequencing predictions. To further simplify the assay and decrease the time to obtain results, the BLIPK74T/W112D protein was tested in combination with the widely used Carba-NP assay. For this purpose, the genome-sequenced K. pneumoniae strains were tested for the presence of carbapenemases with the Carba-NP test with and without the addition of BLIPK74T/W122D The test accurately identified carbapenemase-producing strains and the addition of BLIPK74T/W112D allowed a further determination that the strains contain KPC carbapenemase. Thus, the BLIPK74T/W112D protein is an effective sensor to specifically detect KPC ß-lactamases produced by clinical isolates.IMPORTANCE Infections caused by carbapenem-resistant Enterobacteriaceae are associated with high therapeutic failure and mortality rates. Thus, it is critical to rapidly identify clinical isolates expressing KPC ß-lactamases to facilitate administration of the correct antibiotic treatment and initiate infection control strategies. To address this problem, we developed a protein-based, KPC-specific binding assay in combination with a cell lysate inhibition assay that provided a 100% identification rate of KPC from clinical isolates of known genomic sequence. In addition, this protein sensor was adapted to the Carba-NP assay to provide a rapid strategy to detect KPC-producing isolates that will facilitate informed treatment of critically ill patients.

20.
Photochem Photobiol ; 96(1): 4-13, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31770464

RESUMO

Microwave-solvothermal synthesized MIL-101(Fe) was successfully loaded by silver halides (AgCl and AgBr) by simple precipitation method. The XRD, FESEM mapping, XPS and DRS measurements reveal the successful fabrication of composite photocatalyst. The results suggested that silver halides altered surface charge, surface area and pore size distribution of MIL-101(Fe). The 20%AgBr@MIL-101(Fe) composite has strong tendency to remove the cationic/anionic dyes (96% of rhodamine B, 100% of malachite green and 92% of methyl orange) from wastewater after 30 min of adsorption and 90 min under visible light irradiation. The composite photocatalyst revealed the photodegradation stability up to four cycles. The formation of mesopores improves the adsorption ability of the composites for large organic molecules, while loaded silver halides might inhibit the recombination of electron-hole pairs; those were responsible for enhancing the photocatalytic degradation of organic pollutants. ESR suggested O 2 · - , · OH were responsible for dye degradation in visible light by composite photocatalysts. The photocatalytic mechanism of the composite was also explained in this work.

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