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1.
Neural Netw ; 121: 396-408, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31604202

RESUMO

In this study, we use a deep convolutional neural network (CNN) to develop a model that predicts ozone concentrations 24 h in advance. We have evaluated the model for 21 continuous ambient monitoring stations (CAMS) across Texas. The inputs for the CNN model consist of meteorology (e.g., wind field, temperature) and air pollution concentrations (NO x and ozone) from the previous day. The model is trained for predicting next-day, 24-hour ozone concentrations. We acquired meteorological and air pollution data from 2014 to 2017 from the Texas Commission on Environmental Quality (TCEQ). For 19 of the 21 stations in the study, results show that the yearly index of agreement (IOA) is above 0.85, confirming the acceptable accuracy of the CNN model. The results also show the model performed well, even for stations with varying monthly trends of ozone concentrations (specifically CAMS-012, located in El-Paso, and CAMS-013, located in Fort Worth, both with IOA=0.89). In addition, to ensure that the model was robust, we tested it on stations where fewer meteorological variables are monitored. Although these stations have fewer input features, their performance is similar to that of other stations. However, despite its success at capturing daily trends, the model mostly underpredicts the daily maximum ozone, which provides a direction for future study and improvement. As this model predicts ozone concentrations 24 h in advance with greater accuracy and computationally fewer resources, it can serve as an early warning system for individuals susceptible to ozone and those engaging in outdoor activities.

2.
Cancers (Basel) ; 11(12)2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31817027

RESUMO

Cancer cachexia is a devastating syndrome characterized by unintentional weight loss attributed to extensive skeletal muscle wasting. The pathogenesis of cachexia is multifactorial because of complex interactions of tumor and host factors. The irreversible wasting syndrome has been ascribed to systemic inflammation, insulin resistance, dysfunctional mitochondria, oxidative stress, and heightened activation of ubiquitin-proteasome system and macroautophagy. Accumulating evidence suggests that deviant regulation of an array of signaling pathways engenders cancer cachexia where the human body is sustained in an incessant self-consuming catabolic state. Recent studies have further suggested that several components of endoplasmic reticulum (ER) stress-induced unfolded protein response (UPR) are activated in skeletal muscle of animal models and muscle biopsies of cachectic cancer patients. However, the exact role of ER stress and the individual arms of the UPR in the regulation of skeletal muscle mass in various catabolic states including cancer has just begun to be elucidated. This review provides a succinct overview of emerging roles of ER stress and the UPR in cancer-induced skeletal muscle wasting.

3.
Indian J Clin Biochem ; 34(4): 379-394, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31686725

RESUMO

Abstract: Tea polyphenols are known to prevent various ailments like cancer, atherosclerosis, hypertension and diabetes. Our study aimed at to decipher the gastroprotective effect of aqueous black tea extract (BTE) against ethanol-induced gastric damage and the role of BTE in modulating MMP-9 activity and expression, both in vivo and in vitro. The protective role of BTE was assessed in Sprague-Dawley rats after inducing damage with 70% ethanol. Human gastric adenocarcinoma cells (AGS) were treated with ethanol in ex vivo experiment. MMP-9 activity and expression were investigated through gelatin zymography and western blotting. Reactive oxygen species (ROS) generation was also studied by fluorescence spectroscopy and confocal microscopy, with or without treatment of BTE both in vivo and in vitro experiments. In addition, the effect of citric acid treated BTE (cBTE), which mimics lemon tea, was examined on ethanol-induced gastropathy. BTE exhibited antiulcer activity through reduction of glutathione depletion, lipid peroxidation, protein oxidation, ROS production and inflammatory cell infiltration in rat gastric tissues. In addition, BTE significantly inhibited synthesis and secretion of proMMP-9 both in vivo and in vitro. The mitochondrial enzymes succinate dehydrogenase and NADH oxidase in rat gastric tissues were downregulated by BTE while protecting gastric ulcer. Citric acid addition to BTE was observer to enrich the lead compound, catechin. Interestingly, cBTE showed higher anti-ulcer activity than the untreated one. BTE shows protective role against ethanol-induced gastric ulcer in rats through scavenging ROS and downregulating proMMP-9 activity. While cBTE shows better protection due to enrichment of catechin and removal of tannins in tea extract leading to enhanced inhibitory role on proMMP-9 activity and ROS production.

4.
PLoS One ; 14(10): e0223765, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31644604

RESUMO

Whitefly-transmitted begomoviruses cause serious damage to many economically important food, feed, and fiber crops. Numerous vegetable crops are severely affected and chilli leaf curl virus (ChiLCV) is the most dominant and widely distributed begomovirus in chilli (Capsicum annuum) throughout the Indian subcontinent. Recently, CRISPR-Cas9 technology was used as a means to reduce geminivirus replication in infected plants. However, this approach was shown to have certain limitations such as the evolution of escape mutants. In this study, we used a novel, multiplexed guide RNA (gRNA) based CRISPR-Cas9 approach that targets the viral genome at two or more sites simultaneously. This tactic was effective in eliminating the ChiLCV genome without recurrence of functional escape mutants. Six individual gRNA spacer sequences were designed from the ChiLCV genome and in vitro assays confirmed the cleavage behaviour of these spacer sequences. Multiplexed gRNA expression clones, based on combinations of the above-mentioned spacer sequences, were developed. A total of nine-duplex and two-triplex CRISPR-Cas9 constructs were made. The efficacy of these constructs was tested for inhibition of ChiLCV infection in Nicotiana benthamiana. Results indicated that all the constructs caused a significant reduction in viral DNA accumulation. In particular, three constructs (gRNA5+4, gRNA5+2 and gRNA1+2) were most effective in reducing the viral titer and symptoms. T7E1 assay and sequencing of the targeted viral genome did not detect any escape mutants. The multiplexed genome-editing technique could be an effective way to trigger a high level of resistance against begemoviruses. To our knowledge, this is the first report of demonstrating the effectiveness of a multiplexed gRNA-based plant virus genome editing to minimize and eliminate escape mutant formation.

5.
Virusdisease ; 30(2): 227-236, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31179361

RESUMO

Tobacco streak virus (TSV, genus Ilarvirus family Bromoviridae) is known to cause stem necrosis disease (SND) in groundnut (Arachis hypogaea) since 2000 in Southern India. The TSV isolate infecting groundnut so far has not been characterized based on the complete genome sequence. In this study, TSV was isolated from a naturally infecting groundnut plant in Kadiri, the hot-spot of the SND in southern India. During the Kharif season of 2014, groundnut plants in an experimental field were affected with chlorosis and necrosis in leaf, stem and buds. The cent percent of the 48 samples with these symptoms collected from the field tested positive for TSV in ELISA samples in this context. One isolate, GN-Kad was established from a single lesion on cowpea cv. C-152 through successive sap inoculation. Cloning and sequencing of coat protein gene (717 nucleotides) of the isolate showed high sequence identity (98-99%) with the TSV isolates reported from different crops in India. The isolate produced local necrotic rings or veinal necrosis following sap inoculation to cowpea (cultivars C-152, Pusa Komal, Pusa Sukomal and Krishi Kanchan), French bean and sunflower; whereas, it produced systemic chlorotic mottling symptoms in Nicotiana benthamiana. The three segments of the virus genome (RNA 1, RNA 2 and RNA 3) contained 3523, 2903 and 2232 nucleotides, respectively. The overall genome sequence (8639 nt) of the present isolate shared 77-99% of nucleotide sequence identity with that of the other seven isolates reported from Australia, India and USA. The GN-Kad shared very close phylogenetic relationship with the okra and pumpkin isolates reported from India. The present report is the first comprehensive study of the molecular characterization of TSV associated with the stem necrosis disease of groundnut.

6.
Environ Int ; 130: 104922, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31226557

RESUMO

Diesel emissions from freight transportation activities are a key threat to public health. This study examined the air quality and public health impacts of projected freight-related emissions in 2050 over the continental United States. Three emission scenarios were considered: (1) a projected business-as-usual socioeconomic growth with freight fleet turnover and stringent emission control (CTR); (2) the application of a carbon pricing climate policy (PO); and (3) further technology improvements to eliminate high-emitting conditions in the truck fleet (NS). The PO and NS cases are superimposed on the CTR case. Using a WRF-SMOKE-CMAQ-BenMAP modeling framework, we quantified the impacts of diesel fine particulate matter (PM2.5) emissions change on air quality, health, and economic benefits. In the CTR case, we simulate a widespread reduction of PM2.5 concentrations, between 0.5 and 1.5 µg m-3, comparing to a base year of 2011. This translates into health benefits of 3600 (95% CI: 2400-4800) prevented premature deaths, corresponding to $38 (95% CI: $3.5-$100) billion. Compared to CTR case, the PO case can obtain ~9% more health benefits nationally, however, climate policy also affects the health outcomes regionally due to transition of demand from truck to rail; regions with fewer trucks could gain in health benefits, while regions with added rail freight may potentially experience a loss in health benefits due to air quality degradation. The NS case provides substantial additional benefits (~20%). These results support that a combination of continuous adoption of stringent emission standards and strong improvements in vehicle technology are necessary, as well as rewarding, to meet the sustainable freight and community health goals. States and metropolitan areas with high population density and usually high freight demand and emissions can take more immediate actions, such as accelerating vehicle technology improvements and removing high-emitting trucks, to improve air quality and health benefits.

7.
Mol Cell Biol ; 39(15)2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31138662

RESUMO

Skeletal muscle wasting causes both morbidity and mortality of cancer patients. Accumulating evidence suggests that the markers of endoplasmic reticulum (ER) stress and unfolded protein response (UPR) pathways are increased in skeletal muscle under multiple catabolic conditions, including cancer. However, the signaling mechanisms and the role of individual arms of the UPR in the regulation of skeletal muscle mass remain largely unknown. In the present study, we demonstrated that gene expression of Toll-like receptors (TLRs) and myeloid differentiation primary response gene 88 (MyD88) was increased in skeletal muscle in a Lewis lung carcinoma (LLC) model of cancer cachexia. Targeted ablation of MyD88 inhibits the loss of skeletal muscle mass and strength in LLC tumor-bearing mice. Inhibition of MyD88 attenuates the LLC-induced activation of the UPR in skeletal muscle of mice. Moreover, muscle-specific deletion of X-box binding protein 1 (XBP1), a major downstream target of IRE1α arm of the UPR, ameliorates muscle wasting in LLC tumor-bearing mice. Our results also demonstrate that overexpression of an active form of XBP1 caused atrophy in cultured myotubes. In contrast, knockdown of XBP1 inhibits myotube atrophy in response to LLC or C26 adenocarcinoma cell conditioned medium. Collectively, our results demonstrate that TLR/MyD88-mediated activation of XBP1 causes skeletal muscle wasting in LLC tumor-bearing mice.


Assuntos
Caquexia/metabolismo , Carcinoma Pulmonar de Lewis/complicações , Fator 88 de Diferenciação Mieloide/metabolismo , Receptores Toll-Like/metabolismo , Proteína 1 de Ligação a X-Box/metabolismo , Animais , Carcinoma Pulmonar de Lewis/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Humanos , Camundongos , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Transdução de Sinais , Resposta a Proteínas não Dobradas , Regulação para Cima , Proteína 1 de Ligação a X-Box/genética
8.
Toxicol Rep ; 5: 1044-1052, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30406021

RESUMO

PC, PCM, PCS, and PCMS are our designed & synthesized ∼8 nm PAMAM dendrimer (P) -based organic supramolecular systems, for example, PCMS has 32 molecular motors (M), 4 pH sensors (S) and 2 multi-level molecular electronic switches (C). We have reported earlier following a preliminary in-vitro test that the synthesized PCMS can selectively target cancer cell nucleotides if triggered wirelessly by an electromagnetic pulse. Here to further verify its drug potential, we have studied the preliminary efficacy, toxicity, and pharmacokinetics of P derivatives (PC, PCM, PCMS) in-vivo and in-vitro. We used ethanol-induced gastric inflammation model and cultured human gastric epithelial cells AGS to examine to the toxicity of PAMAM dendrimers cell permeability and toxicity, in (a) the cultured human gastric epithelium cells (AGS), and in (b) the gastric ulcer mice model. Here we report that the toxicity of PAMAM dendrimer (>G3.5) P can be reduced by adding C, M and S. Gastric ulcer is the primary stage of the manifestation of acute inflammation, even gastric epithelial cancer. Ethanol causes ulceration (ulcer index 30), thus upregulates both pro and active MMP-9. A 50 µl PCMS dose prior to ethanol administration reduces ulceration by ∼80% and downregulates MMP-9 and prevents oxidative damages of gastric tissue by ECM remodeling. Alcohol's inflammation of mouse stomach causes up-regulation of both pro and active MMP-9, resulting in oxidative damages of gastric tissue by ECM remodeling. PCMS in particular dose window reverses & alters ECM remodeling, thus, neutralizing alcohol-induced inflammation & generation of ROS.

9.
Faraday Discuss ; 212(0): 359-381, 2018 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-30311611

RESUMO

Understanding how the electronic structure of an aqueous solute is intricately bound up with the arrangement of a host liquid provides insight into how non-adiabatic photochemistry takes place in the condensed phase. For example, the presence of water provides additional solute-solvent interactions compared to non-polar solvents: changing the stability of ionized products and modifying the energies of low-lying excited valence states, as well as moving the point of intersection between potential surfaces. Thus, the locations and topography of conical intersections between these surfaces also change. The overall impact of the aqueous environment can be to modify the intricate photochemical and non-radiative pathways taking place after photoexcitation. Time-resolved photoelectron spectroscopy (TRPES) in a liquid micro-jet is implemented here to investigate the influence of water on the electronic structure and dynamics of indole, the chromophore of the amino acid tryptophan. TRPES is used to establish ultrafast relaxation pathways that vary as a function of excitation wavelength. In our experiment, aqueous indole was excited with femtosecond pulses centered at 292 nm and 266 nm. The vertical excitation energy of aqueous indole is extracted and found to be lowered by 0.5 eV in water relative to the gas phase. In the TRPES study, the spectral signature of 1La and evidence of solvated electron formation on an ultrafast timescale are observed. Our data also points to a possible contribution of the dissociative πσ* state, which can be accessed by a conical intersection (CI) with the 1La state.

10.
Biochem Pharmacol ; 156: 322-339, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30170097

RESUMO

Potent anticancer activity coupled with absence of toxicity at therapeutic dose established the glycolytic metabolite, methylglyoxal, as a promising candidate against malignant neoplasia. In this preclinical study we illustrate the applicability of methylglyoxal in formulating an optimally designed combination regimen with chemotherapeutic drugs against breast cancer. Results demonstrated a synergistic augmentation in doxorubicin and cisplatin mediated cytotoxicity in human breast cancer cell lines MDA MB 231 & MCF 7 with methylglyoxal co-treatment at metronomic concentrations. The cell death due to combination treatment was significantly prevented by N-Acetylcysteine and the synergistic effects were attenuated in presence of inhibitors for apoptosis and necroptosis, in MDA MB 231 and MCF 7 cells, respectively. Additionally, acridine orange staining and immunoblotting with LC3B antibody indicated the suppression of doxorubicin induced autophagy flux with methylglyoxal co-treatment. This report documents for the first time the preferential targeting of breast cancer stem cells by methylglyoxal. Combination treatment with doxorubicin or cisplatin hindered mammosphere forming efficiency and inclusively eliminated both cancer stem as well as non-stem cancer cells. The synergistic effect was validated in Ehrlich mammary carcinoma cell induced murine ascites model and the combination advantage in vivo was achieved without any additional deleterious effect to liver and kidney. Our present study evidences the implications of methylglyoxal inclusion in adjuvant multimodal chemotherapeutics against breast cancer and offers noteworthy insights into the possible outcome.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Cisplatino/farmacologia , Doxorrubicina/farmacologia , Aldeído Pirúvico/farmacologia , Animais , Antineoplásicos/farmacologia , Apoptose , Autofagia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/administração & dosagem , Doxorrubicina/administração & dosagem , Esquema de Medicação , Sinergismo Farmacológico , Feminino , Humanos , Camundongos , Neoplasias Experimentais , Aldeído Pirúvico/administração & dosagem , Espécies Reativas de Oxigênio , Ensaios Antitumorais Modelo de Xenoenxerto
11.
PLoS One ; 13(4): e0194441, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29617395

RESUMO

Timely and spatially-regulated injectable hydrogels, able to suppress growing tumors in response to conformational transitions of proteins, are of great interest in cancer research and treatment. Herein, we report rapidly responsive silk fibroin (SF) hydrogels formed by a horseradish peroxidase (HRP) crosslinking reaction at physiological conditions, and demonstrate their use as an artificial biomimetic three-dimensional (3D) matrix. The proposed SF hydrogels presented a viscoelastic nature of injectable hydrogels and spontaneous conformational changes from random coil to ß-sheet conformation under physiological conditions. A human neuronal glioblastoma (U251) cell line was used for screening cell encapsulation and in vitro evaluation within the SF hydrogels. The transparent random coil SF hydrogels promoted cell viability and proliferation up to 10 days of culturing, while the crystalline SF hydrogels converted into ß-sheet structure induced the formation of TUNEL-positive apoptotic cells. Therefore, this work provides a powerful tool for the investigation of the microenvironment on the programed tumor cells death, by using rapidly responsive SF hydrogels as 3D in vitro tumor models.


Assuntos
Antineoplásicos/uso terapêutico , Fibroínas/uso terapêutico , Hidrogéis/uso terapêutico , Seda/uso terapêutico , Microambiente Tumoral/efeitos dos fármacos , Apoptose , Linhagem Celular , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Humanos
12.
J Phys Chem B ; 122(14): 3723-3733, 2018 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-29528657

RESUMO

Direct measurements of the valence ionization energies and the reorganization energies of the three aromatic amino acids, l-tyrosine, l-tryptophan, and l-phenylalanine, in aqueous solution using the liquid microjet technique and two different photoemission methods-X-ray photoelectron spectroscopy (XPS) at 175 eV photon energy and resonant two-photon ionization (R2PI) using 2 × 267 nm (2 × 4.64 eV) UV laser light-are reported. l-Tryptophan has the lowest vertical ionization energy, 7.3 eV, followed by tyrosine (7.8 eV) and phenylalanine (∼8.7 eV). Essentially, no variation in recovered orbital energies is observed comparing near threshold ionization to X-ray ionization. Superior sensitivity of the (background-free) R2PI scheme for solutions with very low solute concentration (<2 mM) is demonstrated in contrast to the single-photon XPS measurements, which often requires solute concentrations of 0.1-1 molar. This higher sensitivity along with chemical selectivity of the R2PI technique can be exploited for both spectroscopic assignment and as an analytical tool. The nature of the adiabatic ionization energy for the three aromatic amino acids has been explored by the R2PI approach and by empirically formulating the correlation between the estimated ionization onset with electronic and nuclear relaxation on the excited state surface. Our results have implications for understanding one-electron transfer within enzymes and in redox situations where (ir)reversible deprotonation occurs such as those manifest in the biochemistry of oxidation damage.

13.
Diabetes Technol Ther ; 20(3): 207-221, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29565722

RESUMO

BACKGROUND: Simulations using mathematical models are important for studying, developing, and improving therapies for people with type 1 diabetes. METHODS: The Medtronic CareLink® database was used to create virtual patients with a variety of inter-insulin sensitivities, meal absorption rates, pharmacokinetics, age, and gender. In addition, intra-insulin sensitivities of the virtual patients change over a 24-h cycle. RESULTS: A total of 2087 virtual patients were developed. The time percentage between 70 and 180 mg/dL of the CareLink uploads and the simulated virtual patients was 72.4% (18.6) and 74.1% (16.9), respectively. The time percentage <70 mg/dL of the real continuous glucose monitoring from CareLink uploads and the simulated virtual patients was 1% (2.4) and 1.7% (4.1), respectively. A simulation study with the virtual patients predicted the glycemic distribution after 2 h of insulin suspension as reported in the ASPIRE (Automation to Simulate Pancreatic Insulin Response) clinical trial. The 3 months outcomes of Medtronic's hybrid closed-loop 670G system pivotal trial were also predicted in a simulation study. The time percentage <70 mg/dL was 3.4% and 3.1%, and the time percentage between 71 and 180 mg/dL was 73.8% and 77.7% for 93 pivotal study adults (>18 years) and 90 adult (>28 years) virtual patients, respectively. CONCLUSION: The Medtronic CareLink database was utilized to generate a large number of virtual patients with a variety of insulin sensitivities, pharmacokinetics, and meal absorption rates. This new simulation model can be potentially used to evaluate and prognosticate the outcomes of studies of artificial pancreas algorithms and systems.


Assuntos
Glicemia/análise , Simulação por Computador , Diabetes Mellitus Tipo 1/sangue , Resistência à Insulina/fisiologia , Modelos Teóricos , Pâncreas Artificial , Automonitorização da Glicemia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Sistemas de Infusão de Insulina
14.
J Chromatogr A ; 1537: 1-9, 2018 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-29336807

RESUMO

The facile preparation, characterization and application of a novel magnetic graphene oxide- metal organic framework [Zn2(d-Cam)2(4, 4'-bpy)]n (MGO-ZnCB) as a sorbent for fast, simple and enantioselective capture of chiral drug intermediates are presented in this paper. The MGO-ZnCB nanocomposite, developed by encapsulating MGO nanoparticles into the homochiral metal organic framework of ZnCB, can integrate the advantages from each component endowing the hybrids with improved synergystic effects. The enantioselective performance of MGO-ZnCB was evaluated by dispersive magnetic nanoparticle solid phase extraction (d-MNSPE) of 1, 1'-bi-2-naphthol (BN) and 2, 2'-furoin (Furoin) racemic solutions. Due to the excellent dispersive capability, high stability, relatively larger saturation magnetization and distinct enrichment capacity of MGO-ZnCB, the d-MNSPE method provids good enantioselective separation of these compounds with enantiomeric excess (ee) values as high as 74.8% and 57.4%, respectively. The entire process with BN or Furoin can be completed within 3 min or less. After washing with methanol, the host MGO-ZnCB can be easily recycled and reused six times without any apparent loss of performance. Furthermore, the adsorbed BN and Furoin in nanodomains of the MGO-ZnCB composite were directly investigated for the first time by atomic force microscopy-infrared (AFM-IR) technique.


Assuntos
Química Farmacêutica/métodos , Estruturas Metalorgânicas/química , Nanocompostos/química , Naftóis/química , Extração em Fase Sólida , Adsorção , Compostos Orgânicos/química , Estereoisomerismo
15.
Virus Res ; 243: 60-64, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29031475

RESUMO

Crambe is an important crop grown worldwide for industrial oil and seed meal. Besides the fungal and bacterial diseases, the crop is reported to be infected by tobacco mosaic virus, beet western yellows virus and turnip mosaic virus under experimental condition. Till now, there was no report of natural infection of any begomovirus in this crop. In the present study, a leaf curl disease was observed in germplasm accessions of three species of Crambe (C. abyssinica, C. glabrata and C. hispanica). Based on the symptoms and presence of whitefly population in the field, begomovirus infection was suspected. Molecular characterization through RCA approach, indicated presence of croton yellow vein mosaic virus (CYVMV, KJ747958) and croton yellow vein mosaic betasatellite (CroYVMB, KM229762). Co-agroinoculation of partial dimeric construct of CYVMV with complete dimeric construct of CroYVMB, produced typical leaf curl symptoms in C. abyssinica, whereas, agroinoculation of partial dimeric construct of CYVMV alone could not produce symptoms in the same plant. In contrast, the CYVMV construct alone could produce symptom in Nicotiana benthamiana, a model host for plant virus studies. In N. benthamiana co-inoculation of CroYVMV with CYVMV construct develop more severe symptoms. However, neither the CYVMV construct alone nor the co-inoculation with CroYVMB produce any symptom in Arabidopsis thaliana even with different methods of inoculation. Inoculated Arabidopsis thaliana also did not yield any amplification of the virus as assessed through PCR and rolling circle amplification (RCA). Thus it confirmed that for successful infection in crambe, CYVMV requires betasatellite, while in N. benthamiana, it does not require betasatellite for symptom induction and in Arabidopsis thaliana CYVMV alone or in presence of betasatellite did not replicate and produce any symptom. This study constitutes the first confirmed record of natural infection of a begomovirus in crambe and further confirmed that cognate betasatellite of CYVMV has differential role in infectivity in different hosts.


Assuntos
Begomovirus/isolamento & purificação , Begomovirus/fisiologia , Croton/virologia , Doenças das Plantas/virologia , Animais , Begomovirus/genética , Croton/classificação , DNA Satélite/genética , DNA Satélite/metabolismo , DNA Viral/genética , DNA Viral/metabolismo , Genoma Viral , Hemípteros/fisiologia , Hemípteros/virologia , Índia , Lycopersicon esculentum/virologia , Filogenia , Folhas de Planta/virologia , Tabaco/virologia
16.
Sci Total Environ ; 613-614: 820-828, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28942315

RESUMO

This study investigates a significant biomass burning (BB) event occurred in Colorado of the United States in 2012 using the Community Multi-scale Air Quality (CMAQ) model. The simulation reasonably reproduced the significantly high upper tropospheric O3 concentrations (up to 145ppb) caused by BB emissions. We find the BB-induced O3 was primarily affected by chemical reactions and dispersion during its transport. In the early period of transport, high NOx and VOCs emissions caused O3 production due to reactions with the peroxide and hydroxyl radicals, HO2 and OH. Here, NOx played a key role in O3 formation in the BB plume. The results indicated that HO2 in the BB plume primarily came from formaldehyde (HCHO+hv=2HO2+CO), a secondary alkoxy radical (ROR=HO2). CO played an important role in the production of recycled HO2 (OH+CO=HO2) because of its abundance in the BB plume. The chemically produced HO2 was largely converted to OH by the reactions with NO (HO2+NO=OH+NO2) from BB emissions. This is in contrast to the surface, where HO2 and OH are strongly affected by VOC and HONO, respectively. In the late stages of transport, the O3 concentration was primarily controlled by dispersion. It stayed longer in the upper troposphere compared to the surface due to sustained depletion of NOx. Sensitivity analysis results support that O3 in the BB plume is significantly more sensitive to NOx than VOCs.

17.
Appl Opt ; 56(31): H57-H66, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29091667

RESUMO

This paper reports open-path in situ measurements of atmospheric carbon dioxide at Gandhinagar (23.2156°N, 72.6369°E) and Ahmedabad (23.0225°N, 72.5714°E) in the heavily industrialized state of Gujarat in western India. Calibration-free second harmonic wavelength modulation spectroscopy (2f WMS) is used to carry out accurate and fully automated measurements. The mean values of the mole fraction of carbon dioxide at four locations were 438 ppm, 495 ppm, 550 ppm, and 740 ppm, respectively. These values are much higher than the current global average of 406.67 ppm. A 1 mW, 2004-nm vertical cavity surface-emitting laser is used to selectively interrogate the R16 transition of carbon dioxide at 2003.5 nm (4991.2585 cm-1). The 2f WMS signal corresponding to the gas absorption line shape is simulated using spectroscopic parameters available in the HITRAN database and relevant laser parameters that are extracted in situ from non-absorbing spectral wings of the harmonic signals. The mole fraction of carbon dioxide is extracted in real-time by a MATLAB program from least-squares fit of the simulated 2f WMS signal to the corresponding experimentally obtained signal. A 10-mW, 1392.54-nm distributed feedback laser is used at two of the locations to carry out water vapor measurements using direct absorption spectroscopy. This is the first instance of a portable tunable diode laser spectroscopy system being deployed in an urban location in India to measure atmospheric carbon dioxide and water vapor under varying traffic conditions. The measurements clearly demonstrate the need to adopt tunable diode laser spectroscopy for precise long-term monitoring of greenhouse gases in the Indian subcontinent.

18.
Diabetes Technol Ther ; 19(6): 340-348, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28574723

RESUMO

BACKGROUND: We aimed to compare closed-loop glucose control for people with type 1 diabetes undertaking high-intensity interval exercise (HIIE) versus moderate-intensity exercise (MIE). METHODS: Adults with type 1 diabetes established on insulin pumps undertook HIIE and MIE stages in random order during automated insulin delivery via a closed-loop system (Medtronic). Frequent venous sampling for glucose, lactate, ketones, insulin, catecholamines, cortisol, growth hormone, and glucagon levels was performed. The primary outcome was plasma glucose <4.0 mmol/L for ≥15 min, from exercise commencement to 120 min postexercise. Secondary outcomes included continuous glucose monitoring and biochemical parameters. RESULTS: Twelve adults (age mean ± standard deviation 40 ± 13 years) were recruited; all completed the study. Plasma glucose of one participant fell to 3.4 mmol/L following MIE completion; no glucose levels were <4.0 mmol/L for HIIE (primary outcome). There were no glucose excursions >15.0 mmol/L for either stage. Mean (±standard error) plasma glucose did not differ between stages pre-exercise; was higher during exercise in HIIE than MIE (11.3 ± 0.5 mmol/L vs. 9.7 ± 0.6 mmol/L, respectively; P < 0.001); and remained higher until 60 min postexercise. There were no differences in circulating free insulin before, during, or postexercise. During HIIE compared with MIE, there were greater increases in lactate (P < 0.001), catecholamines (all P < 0.05), and cortisol (P < 0.001). Ketones increased more with HIIE than MIE postexercise (P = 0.031). CONCLUSIONS: Preliminary findings suggest that closed-loop glucose control is safe for people undertaking HIIE and MIE. However, the management of the postexercise rise in ketones secondary to counter-regulatory hormone-induced insulin resistance observed with HIIE may represent a challenge for closed-loop systems.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Exercício , Treinamento Intervalado de Alta Intensidade , Hiperglicemia/prevenção & controle , Hipoglicemia/prevenção & controle , Pâncreas Artificial , Adulto , Biomarcadores/sangue , Glicemia , Terapia Combinada/efeitos adversos , Estudos Cross-Over , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/metabolismo , Feminino , Hemoglobina A Glicada/análise , Treinamento Intervalado de Alta Intensidade/efeitos adversos , Humanos , Resistência à Insulina , Corpos Cetônicos/sangue , Ácido Láctico/sangue , Masculino , Pessoa de Meia-Idade , Pâncreas Artificial/efeitos adversos , Vitória
20.
Diabetes Technol Ther ; 19(7): 410-416, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28537437

RESUMO

BACKGROUND: This qualitative study explored trial participants' experiences of four nights of in-home closed loop. METHODS: Sixteen adults with type 1 diabetes, who completed a randomized crossover trial, were interviewed after four consecutive nights of closed-loop. Interviews were audio recorded, transcribed, and analyzed with a coding framework developed to identify the main themes. RESULTS: Participants had a mean age of 42 ± 10 years, nine were women; mean diabetes duration was 27 ± 7 years, and all were using insulin pumps. Overall, first impressions were positive. Participants found closed-loop easy to use and understand. Most experienced more stable overnight glucose levels, although for some these were similar to usual care or higher than they expected. Compared with their usual treatment, they noticed the proactive nature of the closed-loop, being able to predict trends and deliver micro amounts of insulin. Most reported technical glitches or inconveniences during one or more nights, such as transmission problems, problematic connectivity between devices, ongoing alarms despite addressing low glucose levels, and sensor inaccuracy. Remote monitoring by the trial team and their own hypoglycemic awareness contributed to feelings of trust and safety. Although rare, safety concerns were raised, related to feeling unsure whether the system would respond in time to falling glucose levels. CONCLUSIONS: This study provides relevant insights for implementation of closed-loop in the real world. For people with diabetes who are less familiar with technology, remote monitoring for the first few days may provide reassurance, strengthen their trust/skills, and make closed-loop an acceptable option for more people with type 1 diabetes.


Assuntos
Automonitorização da Glicemia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Sistemas de Infusão de Insulina , Adulto , Glicemia/análise , Estudos Cross-Over , Diabetes Mellitus Tipo 1/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa
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