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1.
Chemistry ; 29(36): e202300956, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37072374

RESUMO

Divalent lanthanoid pseudo-Grignard reagents PhLnBr (Ln=Sm, Eu and Yb) can be easily prepared by the oxidative addition of bromobenzene (PhBr) to lanthanoid metals in tetrahydrofuran (THF). PhLnBr reacts with bulky N,N'-bis(2,6-di-isopropylphenyl)formamidine (DippFormH) to generate LnII complexes, namely [Ln(DippForm)Br(thf)3 ]2 ⋅6thf (1; Sm, 2; Eu), and [Yb(DippForm)Br(thf)2 ]2 ⋅2thf (3; Yb). Samarium and europium (in 1 and 2) are seven coordinate, whereas ytterbium (in 3) is six coordinate, and all are bromine-bridged dimers. When PhLnBr reacts with 3,5-diphenylpyrazole (Ph2 pzH), both divalent (5; [Eu(Ph2 pz)2 (thf)4 ]) and trivalent (4 a; [Sm(Ph2 pz)3 (thf)3 ]⋅3thf, 4 b; [Sm(Ph2 pz)3 (dme)2 ]⋅dme) complexes are obtained. In the monomeric compounds 4(a,b), samarium is nine coordinate but europium is eight coordinate in 5. The use of PhLnBr in this work transforms the outcomes from earlier reactions of PhLnI.

2.
Environ Sci Technol ; 57(41): 15475-15486, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37788297

RESUMO

Urbanization has degraded ecosystem services on a global scale, and cities are vulnerable to long-term stresses and risks exacerbated by climate change. Green infrastructure (GI) has been increasingly implemented in cities to improve ecosystem functions and enhance city resilience, yet GI degradation or failure is common. Biochar has been recently suggested as an ideal substrate additive for a range of GI types due to its favorable properties; however, the generality of biochar benefits the GI ecosystem function, and the underlying mechanisms remain unclear. Here, we present a global meta-analysis and synthesis and demonstrate that biochar additions pervasively benefit a wide range of ecosystem functions on GI. Biochar applications were found to improve substrate water retention capacity by 23% and enhance substrate nutrients by 12-31%, contributing to a 33% increase in plant total biomass. Improved substrate physicochemical properties and plant growth together reduce discharge water volume and improve discharge water quality from GI. In addition, biochar increases microbial biomass on GI by ∼150% due to the presence of biochar pores and enhanced microbial growth conditions, while also reducing CO2 and N2O emissions. Overall results suggest that biochar has great potential to enhance GI ecosystem functions as well as urban sustainability and resilience.


Assuntos
Ecossistema , Crescimento Sustentável , Cidades , Carvão Vegetal/química , Solo/química
3.
Org Biomol Chem ; 15(45): 9727-9733, 2017 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-29130464

RESUMO

To address carbohydrates that are commonly used in biomedical applications with low binding affinities for boronic acid based detection systems, two chemical modification methods were utilized to increase sensitivity. Modified carbohydrates were analyzed using a two component fluorescent probe based on boronic acid-appended viologen-HPTS (4,4'-o-BBV). Carbohydrates normally giving poor signals (fucose, l-rhamnose, xylose) were subjected to sodium borohydride (NaBH4) reduction in ambient conditions for 1 h yielding the corresponding sugar alcohols from fucose, l-rhamnose and xylose in essentially quantitative yields. Compared to original aldoses, apparent binding affinities were increased 4-25-fold. The chlorinated sweetener and colon permeability marker sucralose (Splenda), otherwise undetectable by boronic acids, was dechlorinated to a detectable derivative by reactive oxygen and hydroxide intermediates by the Fenton reaction or by H2O2 and UV light. This method is specific to sucralose as other common sugars, such as sucrose, do not contain any carbon-chlorine bonds. Significant fluorescence response was obtained for chemically modified sucralose with the 4,4'-o-BBV-HPTS probe system. This proof of principle can be applied to biomedical applications, such as gut permeability, malabsorption, etc.


Assuntos
Ácidos Borônicos/química , Carboidratos/análise , Fluorescência , Corantes Fluorescentes/química , Monossacarídeos/química , Sacarose/análogos & derivados , Pesquisa Biomédica , Sacarose/química
4.
Am J Physiol Gastrointest Liver Physiol ; 309(8): G625-34, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26206857

RESUMO

Neuropeptide S (NPS) receptor (NPSR1) polymorphisms are associated with enteral dysmotility and inflammatory bowel disease (IBD). This study investigated the role of NPS in conjunction with nitrergic mechanisms in the regulation of intestinal motility and mucosal permeability. In rats, small intestinal myoelectric activity and luminal pressure changes in small intestine and colon, along with duodenal permeability, were studied. In human intestine, NPS and NPSR1 were localized by immunostaining. Pre- and postprandial plasma NPS was measured by ELISA in healthy and active IBD humans. Effects and mechanisms of NPS were studied in human intestinal muscle strips. In rats, NPS 100-4,000 pmol·kg(-1)·min(-1) had effects on the small intestine and colon. Low doses of NPS increased myoelectric spiking (P < 0.05). Higher doses reduced spiking and prolonged the cycle length of the migrating myoelectric complex, reduced intraluminal pressures (P < 0.05-0.01), and increased permeability (P < 0.01) through NO-dependent mechanisms. In human intestine, NPS localized at myenteric nerve cell bodies and fibers. NPSR1 was confined to nerve cell bodies. Circulating NPS in humans was tenfold below the ∼0.3 nmol/l dissociation constant (Kd) of NPSR1, with no difference between healthy and IBD subjects. In human intestinal muscle strips precontracted by bethanechol, NPS 1-1,000 nmol/l induced NO-dependent muscle relaxation (P < 0.05) that was sensitive also to tetrodotoxin (P < 0.01). In conclusion, NPS inhibits motility and increases permeability in neurocrine fashion acting through NO in the myenteric plexus in rats and humans. Aberrant signaling and upregulation of NPSR1 could potentially exacerbate dysmotility and hyperpermeability by local mechanisms in gastrointestinal functional and inflammatory reactions.


Assuntos
Motilidade Gastrointestinal/fisiologia , Mucosa Intestinal/metabolismo , Neuropeptídeos/metabolismo , Óxido Nítrico/metabolismo , Adulto , Animais , Betanecol , Biomarcadores , Regulação da Expressão Gênica/fisiologia , Humanos , Inflamação/metabolismo , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Neuropeptídeos/sangue , Neuropeptídeos/farmacologia , Óxido Nítrico Sintase Tipo I/genética , Óxido Nítrico Sintase Tipo I/metabolismo , Permeabilidade , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Neuropeptídeos/genética , Receptores de Neuropeptídeos/metabolismo
5.
Heliyon ; 10(9): e30148, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38720698

RESUMO

This study aims to analyze the impact of trade openness and Sustainable Development Goals, Financial Development, and Technology on the economic growth of Brazil, Russia, India, China and Colombia, Indonesia, Vietnam, Egypt, Turkey, South Africa countries. The present analysis employs a balanced panel data set from 1996 to 2022. This study also uses various tests, such as the Johansen-Fisher cointegration and Granger causality test. The study's findings suggest that economic growth, trade openness, Sustainable Development Goals, financial development, inflation, technology, labor forces, and financial openness have a long-term relationship among them. In the long run, a positive relationship exists between economic growth, trade openness, and the sustainable development goals index in (BRIC) and (CIVETS) countries. Based on the heterogeneous panel non-causality tests, the findings demonstrate that trade openness and Sustainable Development Goals are a unidirectional causality between trade openness, Sustainable Development Goals, and economic growth.

6.
Sci Total Environ ; 930: 172666, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38653415

RESUMO

The net effect of forest disturbances, such as fires and harvesting, on soil greenhouse gas fluxes is determined by their impacts on both biological and physical factors, as well as the temporal dynamics of these effects post-disturbance. Although harvesting and fire may have distinct effects on soil carbon (C) dynamics, the temporal patterns in soil CO2 and CH4 fluxes and the potential differences between types of disturbances, remain poorly characterized in boreal forests. In this study, we measured soil CO2 and CH4 fluxes using a off-axis integrated cavity output spectroscopy system in snow-free seasons over two years in post-harvest and post-fire chronosequence sites within a mixedwood boreal forest in northwestern Ontario, Canada. Soil CO2 efflux showed a post-disturbance peak, with differing dynamics depending on the disturbance type: post-harvest stands exhibited a nearly tenfold increase (from ∼1 to ∼11 µmol CO2.m-2.s-1) from 1 to 9-10 years post-disturbance, followed by a steep decline; post-fire stands showed a more gradual increase, peaking at ∼6-7.2 µmol CO2.m-2.s-1 after ∼12-15 years. The youngest post-harvest stands were net sources of CH4,whereas post-fire stands were never net CH4 sources. In both disturbance types, the strength of the CH4 sink increased with stand age, approaching ∼2.4 nmol.m-2.s-1 by 15 years post-disturbance. Volumetric water content, bulk density, litter depth, and pH were significant predictors of CO2 fluxes; for CH4 fluxes, litter depth, pH, and the interaction of VWC and soil temperature were significant predictors in both disturbance types, with EC also showing a relationship in post-harvest stands. Our findings indicate that while soil CH4 oxidation rapidly recovers following disturbance, both post-harvest and post-fire stands show a multi-decade release of soil CO2 that is too large to be offset by C gains over this period.

7.
Chem Asian J ; 18(14): e202300333, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37203372

RESUMO

This paper describes a novel and simple method - direct reaction of lanthanoid metals with equimolar amounts of iodine and a formamidine under ultrasonication as an effective, metal-based route to lanthanoid(III) diiodide formamidinates, namely I. N,N'-Bis(2,6-diisopropylphenyl)formamidinatodiiodidolanthanoid(III) complexes [Ln(DippForm)I2 (thf)3 ] (Ln=La, 1, Ce, 2, Tb, 3, Ho, 4, Er, 5, Tm, 6); II. N,N'-Bis(2,6-diethylphenyl)formamidinatodiiodidolanthanoid(III) complexes [Ln(EtForm)I2 (thf)3 ] (Ln=Ce, 7, Nd, 8, Gd, 9, Tb, 10, Dy, 11, Ho, 12, Er, 13, Lu, 14). III. N,N'-bis(2,6-dimethylphenyl)formamidinatodiiodidolanthanoid(III) complexes [Ln(XylForm)I2 (thf)3 ] (Ln=Ce, 15, Nd, 16, Gd, 17, Tm, 18, Lu 19); IV. N,N'-bis(phenyl)formamidinatodiiodidolanthanoid complexes [Ln(PhForm)I2 (thf)3 ] (Ln=Nd, 20, Gd, 21, Er, 22). Compound [Ce(XylForm)2 I(thf)2 ] (23) was also synthesized by the same method except the ratio of I2 to XylFormH was 1 : 4. Divalent N,N'-bis(2,6-diisopropylphenyl)formamidinato-iodido-lanthanoid(II) complexes [Eu(DippForm)I(thf)4 ] ⋅ thf (24), [Yb(DippForm)I(thf)3 ] ⋅ 2DippFormH (25), [Sm(DippForm)I(thf)4 ] ⋅ thf (26) have also been synthesized by direct reactions of the free metals, iodine and DippFormH. Interestingly, [Sm(DippForm)I2 (thf)3 ] (27) was obtained by the oxidation of [Sm(DippForm)I(thf)4 ] ⋅ thf (26) on exposure to air. N,N'-Bis(2,6-dimethylphenyl)formamidinatoiodidosamarium(II) [Sm(XylForm)I(thf)3 ]n (28) was also prepared by direct reaction of Sm, iodine and XylFormH (mole ratio of I2 : XylFormH=1 : 2). All products have been identified by X-ray crystallography and all the trivalent complexes [Ln(Form)n I3-n ] (n=1 or 2) are stable to rearrangement.

8.
ACS Appl Mater Interfaces ; 15(46): 53568-53583, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37943692

RESUMO

Tetracyanonickelate (TCN)-based metal-organic frameworks (MOFs) show great potential in electrochemical applications such as supercapacitors due to their layered morphology and tunable structure. This study reports on improved electrochemical performance of exfoliated manganese tetracyanonickelate (Mn-TCN) nanosheets produced by the heat-assisted liquid-phase exfoliation (LPE) technique. The structural change was confirmed by the Raman frequency shift of the C≡N band from 2177 to 2182 cm-1 and increased band gap from 3.15 to 4.33 eV in the exfoliated phase. Statistical distribution obtained from atomic force microscopy (AFM) shows that 50% of the nanosheets are single-to-four-layered and have an average lateral size of ∼240 nm2 and thickness of ∼1.2-4.8 nm. High-resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED) patterns suggest that the material maintains its crystallinity after exfoliation. It exhibits an almost 6-fold improvement in specific capacitance (from 13.0 to 72.5 F g-1) measured at a scan rate of 5 mV s-1 in 1 M KOH solution. Galvanostatic charge-discharge (GCD) measurement shows a capacity enhancement from ∼18 F g-1 in the bulk phase to ∼45 F g-1 in the exfoliated phase at a current density of 1 A g-1. Bulk crystals exhibit an increasing trend of capacitance retention by ∼125% over 1000 charge-discharge cycles attributed to electrochemical exfoliation. Electrochemical impedance spectroscopy (EIS) demonstrates a 5-fold reduction in the total equivalent series resistance (ESR) from 4864 Ω (bulk) to 1089 Ω (exfoliated). The enhanced storage capacity in the exfoliated phase results from the combined effect of the electrochemical double-layer charge storage mechanism at the nanosheet-electrolyte interface and the Faradic process characteristic of the pseudocapacitive charge storage behavior.

9.
Heliyon ; 8(12): e12279, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36590560

RESUMO

[This corrects the article DOI: 10.1016/j.heliyon.2022.e10512.].

10.
PLoS One ; 17(6): e0270684, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35759475

RESUMO

Global vaccination coverage is an urgent need to recover the recent pandemic COVID-19. However, people are concerned about the safety and efficacy of this vaccination program. Thus, it has become crucial to examine the knowledge, attitude, and hesitancy towards the vaccine. An online cross-sectional survey was conducted among university students of Bangladesh. Total of 449 university students participated. Most of these students used the internet (34.74%), social media (33.41%), and electronic media (25.61%) as a source of COVID-19 vaccine information. Overall, 58.13% and 64.81% of university students reported positive knowledge and attitude towards the COVID-19 vaccine. 54.34% of these students agreed that the COVID-19 vaccine is safe and effective. 43.88% believed that the vaccine could stop the pandemic. The Spearman's Rank correlation determined the positive correlation between knowledge and attitude. The negative correlation was determined between positive knowledge and hesitancy, and positive attitude and hesitancy. University students with positive knowledge and attitude showed lower hesitancy. Multiple logistic regression analyses determined the university type and degree major as the predictors of knowledge, whereas only degree major was the predictor of attitudes. 26.06% of the study population showed their hesitancy towards the vaccine. University type and degree major were also determined as predictors of this hesitancy. They rated fear of side effects (87.18%) and lack of information (70.94%) as the most reasons for the hesitancy. The findings from this study can aid the ongoing and future COVID-19 vaccination plan for university students. The national and international authorities can have substantial information for a successful inoculation campaign.


Assuntos
COVID-19 , Transtornos Urinários , Vacinas , Bangladesh , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Estudantes , Universidades
11.
Health Sci Rep ; 4(4): e451, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34938896

RESUMO

INTRODUCTION: COVID-19 has become a global public health concern. Safe and effective vaccines are required to control the pandemic. However, positive perception toward the vaccine is also necessary for a successful vaccination effort. OBJECTIVE: A rapid online survey was conducted to evaluate the status and perception toward the newly administered COVID-19 vaccine among the adult population (18 years and above) of Bangladesh. METHODS: A total of 850 adult people participated. χ 2 or Fisher's exact test was performed to determine the association between the first dose of vaccination and sociodemographic information. Logistic regression analyses were carried out to examine the predictors of knowledge, attitude, and hesitation toward the vaccine. RESULTS: Exactly 24.12% of the study population received their first dose of COVID-19 vaccine, whereas 30.23% expressed hesitation about pursuing the vaccine. Older age groups (>70%), married people (49.62%), capital Dhaka city outsiders (32.76%), and high-income groups (>50%) received the vaccine much higher than their counter group. Age, marital status, educational attainment, monthly income, and prior COVID-19 positive status were all significantly associated with the knowledge regarding the vaccine. Only age (>55 years age group = aOR: 4.10; 95% CI: 1.30, 14.31) and level of knowledge (poor knowledge = aOR: 0.17; 95% CI: 0.12, 0.23) were significant determinants of attitudes. In case of hesitation, age group and monthly income were found as significant determinants. Fear of adverse consequences (86.67%) was the most common reason for hesitation, followed by insufficient information (73.85%). CONCLUSION: This study sought to determine the status and perception of the newly administered COVID-19 vaccine to aid in the current inoculation campaign's effectiveness. Collaboration between academics, government officials, and communities is essential in developing a successful COVID-19 vaccination program for the entire population. The authority should develop effective strategies to ensure the implementation of its policy of widespread COVID-19 vaccination coverage.

12.
Environ Monit Assess ; 161(1-4): 453-72, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19266304

RESUMO

Probable sources and mechanisms of arsenic (As) release in shallow aquifer in eastern Bangladesh are evaluated using statistical analysis of groundwater compositions. Dissolved As in 39 samples ranged from 8.05 to 341.5 microg/L with an average of 95.14 microg/L. Ninety seven percent of wells exceed the WHO limit (10 microg/L) for safe drinking water. Principal component analysis is applied to reduce 16 measured compositional variables to five significant components (principal components--PCs) that explain 86.63% of the geochemical variance. Two component loadings, namely PC 1 and PC 2 (45.31% and 23.05%) indicate the natural processes within the aquifers in which organic matter is a key reactant in the weathering reactions. Four groups of wells are defined by the PCA and each group of wells represents distinct physicochemical characteristics. Among them, group III groundwater shows higher As concentration together with high concentrations of Fe, Mn, dissolved organic carbon, PO4(3-) and HCO3(-) than groups I and II. Speciation calculations suggest that only wells of group III are saturated with respect to siderite, and all groups of samples are supersaturated with respect of rhodochrosite. The relationship of As with these parameters in the different groups of wells of the study area suggests that reductive dissolution of Fe-Mn oxyhydroxides with microbially mediated degradation of organic matter is considered to be the dominant processes to release As in groundwater.


Assuntos
Arsênio/análise , Análise de Componente Principal/métodos , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Bangladesh , Carbono/análise , Monitoramento Ambiental/métodos , Geografia , Ferro/análise , Manganês/análise , Movimentos da Água
13.
J Agric Food Chem ; 68(47): 13497-13529, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33170689

RESUMO

Food is the major cadmium (Cd)-exposure pathway from agricultural soils to humans and other living entities and must be reduced in an effective way. A plant can select beneficial microbes, like plant-growth-promoting rhizobacteria (PGPR), depending upon the nature of root exudates in the rhizosphere, for its own benefits, such as plant growth promotion as well as protection from metal toxicity. This review intends to seek out information on the rhizo-immobilization of Cd in polluted soils using the PGPR along with plant nutrient fertilizers. This review suggests that the rhizo-immobilization of Cd by a combination of PGPR and nanohybrid-based plant nutrient fertilizers would be a potential and sustainable technology for phytoavailable Cd immobilization in the rhizosphere and plant cellular detoxification, by keeping the plant nutrition flow and green dynamics of plant nutrition and boosting the plant growth and development under Cd stress.


Assuntos
Bactérias/metabolismo , Cádmio/metabolismo , Plantas/metabolismo , Microbiologia do Solo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodegradação Ambiental , Desenvolvimento Vegetal , Plantas/microbiologia , Rizosfera
14.
Sci Rep ; 8(1): 16859, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30443005

RESUMO

Scientists unequivocally agree that winter air temperature (TA) in northern high latitudes will increase sharply with anthropogenic climate change, and that such increases are already pervasive. However, contrasting hypotheses and results exist regarding the magnitude and even direction of changes in winter soil temperature (TS). Here we use field and satellite data to examine the 'cold soil in a warm world' hypothesis for the first time in the boreal forest using a proxy year approach. In a proxy warm year with a mean annual temperature similar to that predicted for ~2080, average winter TS was reduced relative to the baseline year by 0.43 to 1.22 °C in open to forested sites. Similarly, average minimum and maximum winter TS declined, and the number of freeze-thaw events increased in the proxy warm year, corresponding to a reduction in the number of snow-covered days relative to the baseline year. Our findings indicate that early soil freezing as a result of delayed snowfall and reduced snow insulation from cold winter air are the main drivers of reduced winter active-layer TS (at ~2-cm depth) under warming conditions in boreal forest, and we also show that these drivers interact strongly with forest stand structure.

15.
J Clin Endocrinol Metab ; 103(2): 575-585, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29177486

RESUMO

Context: Glucagon-like peptide-1 (GLP-1) secretion from l-cells and postprandial inhibition of gastrointestinal motility. Objective: Investigate whether physiological plasma concentrations of GLP-1 inhibit human postprandial motility and determine mechanism of action of GLP-1 and analog ROSE-010 action. Design: Single-blind parallel study. Setting: University hospital laboratory. Participants: Healthy volunteers investigated with antroduodenal manometry. Human gastric and intestinal muscle strips. Interventions: Motility indices (MIs) obtained before and during GLP-1 or saline infusion. Plasma GLP-1 and glucagon-like peptide-2 (GLP-2) measured by radioimmunoassay. Gastrointestinal muscle strips investigated for GLP-1- and ROSE-010-induced relaxation employing GLP-1 and GLP-2 and their receptor localization, and blockers exendin(9-39)amide, Lω-nitro-monomethylarginine (L-NMMA), 2',5'-dideoxyadenosine (DDA), and tetrodotoxin (TTX) to reveal target mechanism of GLP-1 action. Main Outcome Measures: Postprandial gastrointestinal relaxation by GLP-1. Results: In humans, food intake increased MI to 6.4 ± 0.3 (antrum), 5.7 ± 0.4 (duodenum), and 5.9 ± 0.2 (jejunum). GLP-1 administered intravenously raised plasma GLP-1, but not GLP-2. GLP-1 0.7 pmol/kg/min suppressed corresponding MI to 4.6 ± 0.2, 4.7 ± 0.4, and 5.0 ± 0.2, whereas 1.2 pmol/kg/min suppressed MI to 5.4 ± 0.2, 4.4 ± 0.3, and 5.4 ± 0.3 (P < 0.0001 to 0.005). In vitro, GLP-1 and ROSE-010 prevented contractions by bethanechol and electric field stimulation (P < 0.005 to 0.05). These effects were disinhibited by exendin(9-39)amide, L-NMMA, DDA, or TTX. GLP-1 and GLP-2 were localized to epithelial cells, GLP-1 also at myenteric neurons. GLP-1R and GLP-2R were localized at myenteric neurons but not muscle. Conclusions: GLP-1 and ROSE-010 inhibit postprandial gastrointestinal motility through GLP-1R at myenteric neurons, involving nitrergic and cyclic adenosine monophosphate-dependent mechanisms.


Assuntos
Motilidade Gastrointestinal/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Plexo Mientérico/efeitos dos fármacos , Adolescente , Adulto , Duodeno/efeitos dos fármacos , Esvaziamento Gástrico/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Voluntários Saudáveis , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Plexo Mientérico/fisiologia , Fragmentos de Peptídeos/farmacologia , Antro Pilórico/efeitos dos fármacos , Método Simples-Cego , Adulto Jovem
16.
AMB Express ; 7(1): 208, 2017 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-29164352

RESUMO

Salinity is one of the major factors contributing to the loss of crop productivity and thereby impacting livelihood of people in more than 100 countries of the world and the area of land affected by salinity is increasing day by day. This will worsen due to various factors such as drought that might result in high soil salinity. Use of plant growth promoting rhizobacteria is one of the promising eco-friendly strategies for salinity stress management as part of sustainable agricultural practices. However, it requires selecting rhizobacteria with good survivability and adaptation to salt stress. In this study we report aggregation of Methylobacterium oryzae CBMB20 cells grown in media containing high C/N ratio (30:1) than in media containing low C/N ratio (7:1). Aggregated Methylobacterium oryzae CBMB20 cells exhibited enhanced tolerance to UV irradiation, heat, desiccation, different temperature regimes, oxidative stress, starvation and supported higher population in media. Poly-ß-hydroxybutyrate accumulation, exopolysaccharide production, proline accumulation and biofilm formation were good at 100 mM salt concentration with good microbial cell hydrophobicity at both 50 and 100 mM than other concentrations. Both the aggregated and non-aggregated cells grown under 0-200 mM salt concentrations produced IAA even at 200 mM salt concentration with a peak at 100 mM concentration with aggregated cells producing significantly higher quantities. ACC deaminase activity was observed in all NaCl concentrations studied with gradual and drastic reduction in aggregated and non-aggregated cells over increased salt concentrations.

17.
Naunyn Schmiedebergs Arch Pharmacol ; 386(1): 41-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23179899

RESUMO

YF476 differs from the proton pump inhibitor (PPI) esomeprazole in mode of action by antagonizing the type 2 receptor of cholecystokinin/gastrin (CCK-2R). YF476 protection against diclofenac-induced gastric ulcers was compared to esomeprazole and correlated with plasma levels of hormones related to gastric pH (gastrin, ghrelin, and somatostatin), gastric gene expression of these hormones, their receptors, and inducible nitric oxide synthase (iNOS). YF476 or esomeprazole pretreatments were followed by diclofenac. Four hours later, gastric tissue was excised and analyzed for ulcer index. An intragastrically implanted Bravo capsule measured pH for 5 days during YF476 plus pentagastrin treatment. Changes in gene expression were assayed for gastrin, ghrelin, and somatostatin; their receptors; and iNOS. YF476 acutely (within 4 h) protected against diclofenac-induced gastric ulcers equivalent to esomeprazole. Gastric pH recorded during 5 days in the presence of pentagastrin was 1.83 (±0.06). YF476 raised pH to 3.67 (±0.09) and plasma ghrelin, gastrin, and somatostatin increased. YF476 increased gene expression of somatostatin receptor and gastrin, while ghrelin receptor decreased; transcripts coding ghrelin, somatostatin, and CCK-2R remained unchanged. In the presence of diclofenac, esomeprazole increased expression of all these transcripts and that of iNOS, while YF476 yielded only decreased CCK-2R and increased iNOS transcripts. YF476 is a potential new preventative treatment for patients at risk of nonsteroidal antiinflammatory drug (NSAID)-induced ulceration. Gastric gene expressions of ghrelin, gastrin, and somatostatin and their receptors differ between esomeprazole and YF476. Despite these differences and different modes of action to raise gastric pH, both drugs acutely increase iNOS, suggesting iNOS expression parallels pH.


Assuntos
Benzodiazepinonas/farmacologia , Óxido Nítrico Sintase Tipo II/genética , Compostos de Fenilureia/farmacologia , Receptor de Colecistocinina B/antagonistas & inibidores , Úlcera Gástrica/prevenção & controle , Animais , Anti-Inflamatórios não Esteroides/toxicidade , Antiulcerosos/farmacologia , Diclofenaco/toxicidade , Esomeprazol/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Masculino , Ratos , Ratos Sprague-Dawley , Úlcera Gástrica/induzido quimicamente
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