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1.
J Fluoresc ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958908

RESUMO

This study investigates the interaction between titanium oxide nanoparticles (TiO2 NPs) and the heterocyclic fluorophore 6-fluoro,4-hydroxy,2-methylquinoline (6-FHMQ), aiming to understand fluorescence quenching mechanisms and thermodynamic characteristics. Spectroscopic techniques including spectrofluorometry (FL) and spectrophotometry (UV-Vis) were used, with a lifetime decay (τ) of 0.18 ns for 6-FHMQ measured using time correlated single photon counting (TCSPC). The interaction between 6-FHMQ and TiO2 NPs revealed a mix of static and dynamic fluorescence quenching mechanisms, with increasing quenching constants (Ksv) and a higher bimolecular quenching rate constant (Kq). The dynamic nature was highlighted by a temperature-dependent increase in binding sites from 1 to ~ 2. Spontaneous complexation was affirmed by negative change in free energy (ΔG), with negative change in enthalpy (ΔH) and a positive change in entropy (ΔS) values indicating favorable electrostatic and ionic interactions. The impact of varying TiO2 NP concentrations on 6-FHMQ absorption was analyzed using the Benesi-Hildbrand equation, with a quantum yield of 0.61 determined. By forster resonance energy transfer (FRET) theory, the proximity between 6-FHMQ and TiO2 NPs was found to be less than 70 Å. Ground and excited state dipole moments of 6-FHMQ in different solvents were calculated to demonstrate solvent sensing ability and charge transfer properties. Ultimately, this study serves as a testament to the power of scientific innovation in the realms of drug delivery and tissue engineering.

2.
J Obstet Gynaecol Can ; : 102604, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38950878

RESUMO

BACKGROUND: This prospective single-arm study was conducted to understand the expulsion rate of the gestational sac in the management of early pregnancy loss (EPL). METHODS: We recruited 441 participants; 188 met eligibility criteria. Participants were 18 years of age and older who experienced a confirmed early pregnancy loss (<12 weeks gestational age) defined by an intrauterine pregnancy with a non-viable embryonic or anembryonic gestational sac with no fetal heart activity. Participants were given 200 mg of mifepristone pretreatment orally followed by two doses of misoprostol 800 mcg vaginally after 24 and 48 hours. Participants were seen in follow-up on day 14 to confirm the absence of a gestational sac, classified as treatment success. For failed treatment (defined by retained gestational sac), we offered expectant management or a third dose of misoprostol and/or dilatation and curettage (D & C). We followed all participants for 30 days. We collected data on overtreatment for retained products of conception and hospital admissions for adverse events. RESULTS: 181 participants followed the protocol, and 169 (93.3%) participants had a complete expulsion of the gestational sac by the second visit (day 14). Twelve (6.6%) failed the treatment and one had an adverse event of heavy vaginal bleeding requiring D & C. Despite the expulsion of the gestational sac, 29 cases (17.1%) at subsequent follow-up were diagnosed as retained products of conception based on ultrasound assessment of thickened endometrium. CONCLUSION: Pretreatment with mifepristone followed by 2 doses of misoprostol with a 14-day follow-up resulted in a high expulsion rate and is a safe management option for EPL.

3.
J Environ Manage ; 351: 119768, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38100858

RESUMO

The most common type of environmental contamination is petroleum hydrocarbons. Sustainable and environmentally friendly treatment strategies must be explored in light of the increasing challenges of toxic and critical wastewater contamination. This paper deals with the bacteria-producing biosurfactant and their employment in the bioremediation of hydrocarbon-containing waste through a microbial fuel cell (MFC) with Pseudomonas aeruginosa (exoelectrogen) as co-culture for simultaneous power generation. Staphylococcus aureus is isolated from hydrocarbon-contaminated soil and is effective in hydrocarbon degradation by utilizing hydrocarbon (engine oil) as the only carbon source. The biosurfactant was purified using silica-gel column chromatography and characterised through FTIR and GCMS, which showed its glycolipid nature. The isolated strains are later employed in the MFCs for the degradation of the hydrocarbon and power production simultaneously which has shown a power density of 6.4 W/m3 with a 93% engine oil degradation rate. A biogenic Fe2O3 nanoparticle (NP) was synthesized using Bambusa arundinacea shoot extract for anode modification. It increased the power output by 37% and gave the power density of 10.2 W/m3. Thus, simultaneous hydrocarbon bioremediation from oil-contamination and energy recovery can be achieved effectively in MFC with modified anode.


Assuntos
Fontes de Energia Bioelétrica , Petróleo , Biodegradação Ambiental , Técnicas de Cocultura , Bactérias/metabolismo , Petróleo/análise , Hidrocarbonetos/química , Eletrodos
4.
Osteoarthritis Cartilage ; 31(10): 1396-1404, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37500050

RESUMO

OBJECTIVE: To study the association of quantitative medial meniscal position measures with radiographic and symptomatic knee osteoarthritis (OA) progression over 2-4 years. METHODS: The FNIH OAI Biomarkers study comprised 600 participants in four subgroups: 194 case knees with combined structural (medial minimum joint space width (minJSW) loss ≥0.7 mm) and symptomatic (persistent Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale increase ≥9 [0-100 scale]) progression; 200 knees with neither structural nor symptomatic progression; 103 knees with isolated structural and 103 with isolated symptomatic progression. Coronal double echo at steady state (DESS) MRIs were used for segmenting five central slices of the medial meniscus. Associations with progression were examined using logistic regression (adjusted for demographic and clinical data). RESULTS: Greater baseline medial meniscal extrusion was associated with combined structural/symptomatic progression (OR 1.59; 95%CI: [1.25,2.04]). No relationship was observed for tibial plateau coverage or meniscal overlap distance. The two-year increase in meniscal extrusion (OR 1.48 [1.21, 1.83]), and reduction in tibial plateau coverage (OR 0.70 [0.58,0.86]) and overlap distance (OR 0.73 [0.60,0.89]) were associated with combined progression. Greater baseline extrusion was associated with isolated structural and less extrusion with isolated symptomatic progression. The longitudinal increase in meniscal extrusion, and reduction in tibial plateau coverage and overlap distance were associated with structural, but not with symptomatic progression. CONCLUSION: Baseline measures of medial meniscal extrusion were consistently positively associated with combined radiographic/symptomatic progression and with isolated structural, but not with isolated symptomatic progression. These measures may therefore allow one to assess the risk of structural knee OA progression and to monitor interventions restoring meniscal position and function.


Assuntos
Menisco , Osteoartrite do Joelho , Humanos , Meniscos Tibiais/diagnóstico por imagem , Osteoartrite do Joelho/diagnóstico por imagem , Tíbia , Imageamento por Ressonância Magnética , Progressão da Doença , Articulação do Joelho/diagnóstico por imagem
5.
Photochem Photobiol Sci ; 22(8): 1991-2003, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37184774

RESUMO

The present work reports pyridine-based chalones using spectroscopic techniques to use pyridine derivative analysis. The solvatochromic behavior of 3DPP in non-polar, polar protic and aprotic solvents has been investigated experimentally. The photophysical property of the compound in diverse solvents is attributed to the intra-molecular charge transfer interactions. The dipole moment of 3DPP is estimated theoretically and experimentally using various solvatochromic methods. It is observed that there is a bathochromic shift in the emission spectra of 3DPP, which confirms the π → π* transition. Fluorescence quenching of 3DPP is studied. The type of fluorescence quenching mechanism is found to be collisional quenching. A study of FRET theory on 3DPP was carried out with metal ions. There is a considerable energy transfer between 3DPP and metal ions. NLO behaviors of the compound have been revealed with the help of Kurtz-Perry powder technique. Additionally, the title molecule is docked, carried ADMET studies and drug-like activity using in silico tools. It is probed for antifungal activity through bioinformatics kit which showed potential information.

6.
J Fluoresc ; 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37897516

RESUMO

In our work, a novel series of europium (III) (Eu3+) (5, 10 and 15 wt %) doped cobalt tetroxide@cupric oxide (Co3O4@CuO) nanomaterials (NMs) were synthesized by facile coprecipitation method. The synthesized NMs were characterized by XRD (X-ray diffraction), FT-IR (Fourier transform infrared), UV (ultraviolet)-visible absorption spectra, XPS (X-ray photoelectron), BET (Brunauer-Emmett-Teller) analytical methods. Crystal structure studies revealed the formation of polycrystalline nature with monoclinic and cubic phase. The morphology studies of Eu3+x:Co3O4@CuO (x = 5, 10 and 15 wt %) showed petal shape nanoparticles (NPs) with agglomeration. Redshift in optical absorption spectra appeared with a significant impact on the optical band gap as Eu3+ concentration increases on Co3O4@CuO bimetallic oxide NMs. The chemical composition and valence state of the elements confirmed from XPS studies detected the presence of Eu, Cu, Co, O and C elements. An increase in the pore size and surface area resulted as the Eu3+ concentration increased on Co3O4@CuO NMs. However, room temperature photoluminescence (RTPL) spectra of Co3O4@CuO bimetallic oxide NMs at two different excitations (λ excitation = 280 nm, 320 nm) showed sharp, strong emission intensities located at near ultraviolet (NUV) region and weak emissions detected at far ultraviolet (FUV) regions of the RTPL spectrum. Further, visible range emission intensities were displayed by Eu3+:Co3O4@CuO (5, 10 and 15 wt %) NMs when exited at 280 nm. The characteristic white light emission peaks in the visible range of the RTPL spectra showed intense blue, green and orange colours. Emission intensity increases with an increase in Eu3+ concentration on Co3O4@CuO bimetallic oxide NMs. The fluorescence (FL) decay spectra of Eu3+ 10wt% and 15 wt%: Co3O4@CuO NMs showed a decay lifetime of 2.54 and 2.31 ns (ns) attributed to the dynamic, ultrafast excitation energy transfer between Eu3+ (dopant) and Co3O4@CuO (host) NMs. It is proposed that enhanced RTPL emission intensity and FL decay behavior of Eu3+x:Co3O4@CuO NMs closely related to the change in the optical band gap, variation in the crystallite size, formation of more number of oxygen vacancies in the crystal structure of hybrid nanomaterials.

7.
J Phys Chem A ; 127(48): 10128-10138, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38015623

RESUMO

Oxadiazole and triazole are extensively investigated heterocyclic scaffolds in the development of energetic materials. New energetic molecules were designed by replacing 1,2,5-oxadiazole with 2H-1,2,3-triazole in the reported conjugated macrocyclic systems to assess the influence on the energetic properties and stability. In addition, nitro groups were introduced in triazole units (N-functionalization) to improve the energetic performance. Energetic properties, including heat of formation, oxygen balance, density, detonation pressure and velocity, and impact sensitivity, were estimated for these triazole-based macrocycles. The replacement of 1,2,5-oxadiazole with 2H-1,2,3-triazole and 2-nitro-1,2,3-triazole significantly enhances the energy content, detonation performance, and noncovalent interactions. The theoretically computed energetic properties of triazole-based macrocycles reveal high positive heats of formation (1507-2761 kJ/mol), oxygen balance (-88.8 to -22.8%), high densities (1.87-1.90 g/cm3), superior detonation velocities (8.41-9.52 km/s), pressures (26.64-40.55 GPa), acceptable impact sensitivity (27-40 cm), and safety factor (51-290). The overall energetic assessment highlights triazole-based macrocycles as a potential framework that will be useful for developing advanced energetic materials.

8.
Phytopathology ; 112(10): 2072-2083, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35522048

RESUMO

Bacterial wilt, caused by the Ralstonia solanacearum species complex (RSSC), is the most destructive potato disease in Kenya. Studies were conducted to (i) determine the molecular diversity of RSSC strains associated with bacterial wilt of potato in Kenya, (ii) generate an RSSC distribution map for epidemiological inference, and (iii) determine whether phylotype II sequevar 1 strains exhibit epidemic clonality. Surveys were conducted in 2018 and 2019, in which tubers from wilting potato plants and stem samples of potential alternative hosts were collected for pathogen isolation. The pathogen was phylotyped by multiplex PCR and 536 RSSC strains typed at a sequevar level. Two RSSC phylotypes were identified, phylotype II (98.4%, n = 506 [sequevar 1 (n = 505) and sequevar 2 (n = 1)]) and phylotype I (1.6%, n = 30 [sequevar 13 (n = 9) and a new sequevar (n = 21)]). The phylotype II sequevar 1 strains were haplotyped using multilocus tandem repeat sequence typing (TRST) schemes. The TRST scheme identified 51 TRST profiles within the phylotype II sequevar 1 strains with a modest diversity index (HGDI = 0.87), confirming the epidemic clonality of RSSC phylotype II sequevar 1 strains in Kenya. A minimum spanning tree and mapping of the TRST profiles revealed that TRST27 '8-5-12-7-5' is the primary founder of the clonal complex of RSSC phylotype II sequevar 1 and is widely distributed via latently infected seed tubers. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Ralstonia solanacearum , Solanum tuberosum , Quênia/epidemiologia , Filogenia , Doenças das Plantas/microbiologia , Ralstonia , Ralstonia solanacearum/genética , Solanum tuberosum/microbiologia
9.
Skeletal Radiol ; 51(5): 997-1006, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34591163

RESUMO

OBJECTIVE: To explore whether and which quantitative 3D measures of medial and/or lateral meniscus position and size are associated with subsequent medial femorotibial structural progression of knee osteoarthritis and to determine the correlation between central slice and total meniscus measures. MATERIALS AND METHODS: Knees with radiographic osteoarthritis from Osteoarthritis Initiative participants with longitudinal medial MRI-based cartilage thickness and radiographic joint space width (JSW) loss over 12 months were selected. These 37 structural progressor knees (64.7 ± 8.0y, 30.2 ± 4.6 kg/m2, 35% men) were matched 1:1 to 37 non-progressor knees (64.6 ± 9.8y, 30.2 ± 4.4 kg/m2, 35% men) without cartilage thickness or JSW loss. Quantitative measures of meniscus position and size were computed from manual segmentations of coronal baseline MRIs. Cohen's D was used as measure of effect size. RESULTS: Maximum extrusion distance of the total medial meniscus and mean extrusion in the central 5 and in the central slice were greater for progressor than non-progressor knees (Cohen's D 0.58-0.66). No significant differences were observed for medial tibial coverage or mean extrusion (entire meniscus). Among medial meniscus morphology measures, only mean height differed between progressor vs non-progressor knees (Cohen's D 0.40). Among lateral meniscus measures, height and volume were greater in progressor vs. non-progressor knees (Cohen's D 0.46-0.83). Mean extrusion measures were highly correlated between the entire meniscus and the central (r = 0.88) or the central 5 (r = 0.93) slices. CONCLUSIONS: 3D maximum and central medial meniscus extrusion may serve as predictors for subsequent structural progression. Central meniscus extrusion measures could substitute 3D extrusion measurement across the entire meniscus.


Assuntos
Menisco , Osteoartrite do Joelho , Progressão da Doença , Feminino , Humanos , Articulação do Joelho/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Meniscos Tibiais/diagnóstico por imagem , Osteoartrite do Joelho/diagnóstico por imagem , Tíbia
10.
Luminescence ; 36(1): 163-168, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32790047

RESUMO

Continuous monitoring of glucose and sugar sensing plays a vital role in diabetes control. The drawbacks of the present enzyme-based sugar sensors have encouraged the investigation into alternate approaches to design new sensors. The popularity of fluorescence sensors is due to their ability to bind reversibly to compounds containing diol. In this study we investigated the binding ability of phenyl boronic acid P1 for monosaccharides and disaccharides (sugars) in aqueous medium at physiological pH 7.4 using steady-state fluorescence and absorbance. P1 fluorescence was quenched due to formation of esters with sugars. Absorbance and fluorescence measurements led to results that indicated that the sugars studied could be ordered in terms of their affinity to P1, as stated: sucrose > lactose > galactose > xylose > ribose > arabinose. In each case, the slope of modified Stern-Volmer plots was nearly 1, indicating the presence of only a single binding site in boronic acids for sugars. Docking studies were carried out using Schrodinger Maestro v.11.2 software. The binding affinity of phenyl boronic acid P1 with periplasmic protein (PDB ID 2IPM and 2IPL) was estimated using GlideScore.


Assuntos
Ácidos Borônicos , Açúcares , Simulação de Acoplamento Molecular , Monossacarídeos , Espectrometria de Fluorescência
11.
Plant Dis ; 105(4): 770-779, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32720880

RESUMO

Bacterial wilt (BW), caused by Ralstonia solanacearum species complex (RSSC), leads to substantial potato yield losses in Rwanda. Studies were conducted to (i) determine the molecular diversity of RSSC strains associated with BW of potato, (ii) generate an RSSC distribution map for epidemiological inferences, and (iii) test the pathogenicity of predominant RSSC phylotypes on six commercial potato cultivars. In surveys conducted in 2018 and 2019, tubers from wilting potato plants were collected for pathogen isolation. DNA was extracted from 95 presumptive RSSC strain colonies. The pathogen was phylotyped by multiplex PCR and typed at sequevar level. Phylotype II sequevar 1 strains were then haplotyped using multilocus tandem repeat sequence typing (TRST) schemes. Pathogenicity of one phylotype II strain and two phylotype III strains were tested on cultivars Kinigi, Kirundo, Victoria, Kazeneza, Twihaze, and Cruza. Two RSSC phylotypes were identified, phylotype II (95.79%, n = 91) and phylotype III (4.21%, n = 4). This is the first report of phylotype III strains from Rwanda. Phylotype II strains were identified as sequevar 1 and distributed across potato growing regions in the country. The TRST scheme identified 14 TRST haplotypes within the phylotype II sequevar 1 strains with moderate diversity index (HGDI = 0.55). Mapping of TRST haplotypes revealed that a single TRST '8-5-12-7-5' haplotype plays an important epidemiological role in BW of potato in Rwanda. None of the cultivars had complete resistance to the tested phylotypes; the level of susceptibility varied among cultivars. Cultivar Cruza, which is less susceptible to phylotype II and III strains, is recommended when planting potatoes in the fields with history of BW.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Ralstonia solanacearum , Solanum tuberosum , Filogenia , Doenças das Plantas , Ralstonia solanacearum/genética , Ruanda , Virulência/genética
12.
Bioscience ; 70(9): 744-758, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32973407

RESUMO

The geographic pattern of cropland is an important risk factor for invasion and saturation by crop-specific pathogens and arthropods. Understanding cropland networks supports smart pest sampling and mitigation strategies. We evaluate global networks of cropland connectivity for key vegetatively propagated crops (banana and plantain, cassava, potato, sweet potato, and yam) important for food security in the tropics. For each crop, potential movement between geographic location pairs was evaluated using a gravity model, with associated uncertainty quantification. The highly linked hub and bridge locations in cropland connectivity risk maps are likely priorities for surveillance and management, and for tracing intraregion movement of pathogens and pests. Important locations are identified beyond those locations that simply have high crop density. Cropland connectivity risk maps provide a new risk component for integration with other factors-such as climatic suitability, genetic resistance, and global trade routes-to inform pest risk assessment and mitigation.

13.
Luminescence ; 35(6): 845-862, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32142207

RESUMO

An attempt was made to determine the ground state and excited state dipole moments and quantum chemical computations of two coumarin compounds, namely 3-hydroxy-3-[2-oxo-2-(2-oxo-2H-chromen-3-yl)-ethyl]-1,3-dihydro-indol-2-one (3HOCE) and 3-[2-(8-methoxy-2-oxo-2H-chromen-3-yl)-2-oxo-ethylidene]-1,3-dihydro-indol-2-one (3MOCE). Both compounds displayed a red shift with enhancement in solvent polarity. The larger excited state dipole moment indicated the more polar nature of the selected compounds in the excited state than in the ground state. Kinetic stability and chemical reactivity of the selected compounds were studied with help of the quantum chemical properties of the compounds such as frontier molecular orbital analysis using density functional theory calculations with B3LYP/6-311+G (d, p) basis sets. Molecular electrostatic potential, Mulliken charges, natural bond orbital, and nonlinear optical properties were further studied. NBO analysis showed proton transfer within the selected donor-acceptor, depicting the large energy of stabilization for the compounds. The calculated Fukui function inferred the local softness and electrophilicity indices of used solute compounds.


Assuntos
Cumarínicos , Teoria Quântica , Modelos Moleculares , Solventes , Eletricidade Estática
14.
Phytopathology ; 109(11): 1922-1931, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31272278

RESUMO

Bacterial wilt (BW) caused by the Ralstonia solanacearum species complex (RSSC) is a serious threat to potato production in Uganda. However, little is known about the extent of the disease and the type of the pathogen strains involved. A nationwide survey was conducted to study BW prevalence and incidence in potato, and potato tuber and stem samples of potential alternative hosts were collected for pathogen isolation. DNA was extracted from pure cultures for genetic diversity studies. The pathogen was phylotyped by multiplex PCR; then, a subset of isolates was typed at sequevar level. Isolates of the same sequevar were then haplotyped using multilocus tandem repeat sequence typing (TRST) schemes. BW prevalence and incidence in potato farms were 81.4 and 1.7%, respectively. Three RSSC phylotypes were identified, with the majority of the strains belonging to Phylotype II (80%) followed by Phylotype I (18.5%) and III (1.5%). Phylotype I strains belonged to Sequevar 31, and Phylotype II strains belonged to Sequevar 1. Potato-associated Phylotype II Sequevar 1 strains were more diverse (27 TRST haplotypes) than nonpotato Phylotype I (5 TRST haplotypes). Mapping of TRST haplotypes revealed that three TRST haplotypes of Phylotype II Sequevar 1 strains play an important epidemiological role in BW of potato in Uganda being disseminated via latently infected seed.[Formula: see text]Copyright © 2019 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Epidemiologia Molecular , Ralstonia solanacearum , Solanum tuberosum , Tipagem Molecular , Filogenia , Doenças das Plantas/microbiologia , Ralstonia solanacearum/classificação , Ralstonia solanacearum/genética , Solanum tuberosum/microbiologia , Uganda
15.
Luminescence ; 34(8): 924-932, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31332940

RESUMO

Fluorescence quenching and preferential solvation of a coumarin derivative, namely 3-[2-oxo-2-(2-oxo-2H-chromen-3-yl)-ethylidene]-1,3-dihydro-indol-2-one (3OCE), with aniline used as a quencher in solvent mixtures of acetonitrile (AN) and 1,4-dioxane (DX) was carried out at steady state. Suppan's theory of dielectric enrichment was used to understand the nonideality and dielectric enrichment in AN-DX solvent mixtures. The effect of viscosity and dielectric constant variation at room temperature were analyzed. Quenching was characterized using Stern-Volmer plots with an upward curvature. It was found that 3OCE underwent combined static and dynamic quenching that was evident from the quenching rate parameters.


Assuntos
Acetonitrilas/química , Dioxanos/química , Fluorescência , Indóis/química , Estrutura Molecular , Fenômenos Ópticos , Solventes/química , Espectrometria de Fluorescência , Temperatura , Viscosidade
16.
Luminescence ; 33(5): 933-940, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29745063

RESUMO

Photo physical properties of fluorescent organic compounds give an immense improved knowledge on characteristics of excited state that is beneficial to devise innovate molecules and understand their performance in particular applications. Coumarin derivatives have been extensively investigated in this regard. This article narrates steady state fluorescence quenching measurements of a coumarin derivative namely 3-hydroxy-3-[2-oxo-2-(3-oxo-3H-benzo[f]chromen-2-yl)-ethyl]-1,3-dihydro-indol-2-one (3HBCD) in a binary mixture of acetonitrile and 1,4-dioxane. Aniline is used as quencher. Fluorescence intensity is large in acetonitrile and decreases as the percentage of 1,4-dioxane in the solvent mixture increases. With modest quencher concentration a deviation towards the x axis is noticed in the Stern-Volmer (S-V) plots. This downward curvature is interpreted as due to the presence of 3HBCD in different conformers in the lowest energy level. Ground state intramolecular hydrogen bonding formation is observed due to the conformational changes in the solute. Figured estimations of various quenching parameters recommend that, while dynamic quenching prompts linearity in S-V plot at lower quencher concentration, increasing quenching efficiency with increasing medium viscosity suggests that reaction is not entirely controlled by material diffusion. Stern-Volmer constant increases with decreasing medium dielectric constant.


Assuntos
Cumarínicos/química , Corantes Fluorescentes/química , Indóis/química , Espectrometria de Fluorescência/métodos , Acetonitrilas/química , Cumarínicos/análise , Dioxanos/química , Corantes Fluorescentes/análise , Indóis/análise , Estrutura Molecular , Solventes , Viscosidade
17.
J Obstet Gynaecol Can ; 37(12): 1063-71, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26637078

RESUMO

OBJECTIVE: Caesarean section at full cervical dilatation is a challenging procedure with a higher risk of fetal and maternal morbidity. We wished to elicit the essential clinical components of a CS at full dilatation performed skilfully and safely. METHODS: We conducted a prospective study with both qualitative (individual interviews) and quantitative (questionnaire) components. In the qualitative components, senior clinicians were interviewed using open-ended questions regarding techniques used for performance of CS at full cervical dilatation. Interviews were recorded and thematic analysis was performed until saturation was achieved. In the second (quantitative) component of the study, clinicians completed a questionnaire regarding tips and techniques to perform a CS at full cervical dilatation. RESULTS: For the qualitative component, 15 clinicians agreed to participate. There was a 90% (n = 27) response rate to the questionnaire. Common themes from both components of the study included the advice to routinely re-examine the patient (with abdominal and vaginal examinations) in the operating room after induction of anaesthesia to determine pelvic architecture, fetal size, and the station of the presenting part, and especially to assess for progress since the initial decision to perform a CS in the labour room. When the decision is made to proceed with CS, the following modifications to a standard CS technique were suggested: first, to make a more superior transverse uterine incision than usual, and second, to secure each uterine angle separately before uterine closure is commenced in order to identify and manage angle extension and thereby minimize blood loss. Other modifications, such as vaginal disimpaction of the fetal head before beginning the operation, were more controversial. Participants developed their own techniques by combining teaching from senior obstetricians, watching others operate, and learning from their own clinical experience. CONCLUSION: There is an increasing role for good quality clinical training programs on how best to perform complex deliveries such as CS at full cervical dilatation. After identifying the essential components of CS at full cervical dilatation reported by multiple skilled clinicians, these can then be translated into a useful educational tool.


Objectif : La tenue d'une césarienne en présence d'une dilatation cervicale complète constitue une intervention difficile qui donne lieu à un risque accru de morbidité fœtale et maternelle. Nous avons cherché à déterminer les composantes cliniques essentielles de la tenue compétente et en toute sûreté d'une césarienne en présence d'une dilatation cervicale complète. Méthodes : Nous avons mené une étude prospective englobant des composantes tant qualitatives (entrevues individuelles) que quantitatives (questionnaire). Dans le cadre des composantes qualitatives, nous avons interviewé des cliniciens expérimentés au moyen de questions ouvertes portant sur les techniques utilisées pour la tenue d'une césarienne en présence d'une dilatation cervicale complète. Ces entrevues ont été enregistrées et une analyse thématique a été menée jusqu'à l'atteinte de la saturation. Dans le cadre de la deuxième composante (quantitative) de l'étude, nous avons demandé aux cliniciens de remplir un questionnaire portant sur les trucs et les techniques permettant de mener une césarienne en présence d'une dilatation cervicale complète. Résultats : Quinze cliniciens ont consenti à participer à la composante qualitative. Le taux de réponse au questionnaire a été de 90 % (n = 27). Parmi les thèmes fréquemment cités dans les deux composantes de l'étude, on trouvait le conseil de procéder systématiquement au réexamen de la patiente (examens abdominaux et vaginaux) dans la salle d'opération à la suite de l'induction de l'anesthésie, de façon à déterminer l'architecture pelvienne, la taille du fœtus et la station de la partie en présentation, et particulièrement en vue d'évaluer l'évolution de la situation depuis la décision initiale de procéder à une césarienne prise dans la salle de travail. Lorsque les intervenants en viennent à la décision de procéder à une césarienne, l'apport des modifications suivantes à la technique standard a été suggéré : premièrement, pratiquer une incision utérine transversale plus supérieure qu'à l'habitude et, deuxièmement, fixer chacun des angles de l'incision utérine séparément avant d'entamer la fermeture de l'utérus, de façon à identifier et à prendre en charge le ou les prolongements possibles des angles de l'incision utérine et ainsi minimiser la perte sanguine. D'autres modifications, telles que la désinclusion vaginale de la tête fœtale avant le début de l'opération, se sont avérées plus controversées. Les participants ont élaboré leurs propres techniques en amalgamant divers éléments (conseils formulés par des obstétriciens expérimentés, observations de la façon de procéder de leurs collègues et leçons tirées de leur propre expérience). Conclusion : Le rôle des programmes de formation clinique de bonne qualité sur la meilleure façon de procéder à des accouchements complexes (comme la césarienne en présence d'une dilatation cervicale complète) devient de plus en plus important. À la suite de leur identification par de multiples cliniciens expérimentés, les composantes essentielles de la tenue d'une césarienne en présence d'une dilatation cervicale complète peuvent être intégrées dans un outil pédagogique utile.


Assuntos
Cesárea/métodos , Lista de Checagem , Segunda Fase do Trabalho de Parto , Feminino , Humanos , Guias de Prática Clínica como Assunto , Gravidez , Estudos Prospectivos
18.
Phytopathology ; 104(10): 1078-87, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24655290

RESUMO

The disease cycle of Plasmodiophora brassicae consists of a primary phase in root hairs followed by a secondary phase in the root cortex and adjacent tissues. However, the role of root hair infection in subsequent cortical infection and development of P. brassicae is not well understood. To examine the role of the primary and secondary stages separately, inoculation studies with resting spores (source of primary zoospores) and secondary zoospores of a virulent and avirulent pathotype were conducted on canola (Brassica napus). The size of secondary zoospores and number of nuclei were also examined. The zoospores were larger (≈9.6 to 14.4 µm) than in previous reports and all were uninucleate. Inoculation with secondary zoospores alone produced both primary and secondary infection, even with the avirulent pathotype. No symptoms developed from inoculation with avirulent primary zoospores but tiny, bead-shaped clubs developed from inoculation with avirulent secondary zoospores. Inoculation with virulent secondary zoospores alone resulted in lower disease severity than inoculation with virulent resting spores alone. The results indicate that recognition of infection by the host and initiation of a response (induction or suppression of resistance) occurs during primary infection, although recognition can also occur during cortical infection and development.


Assuntos
Brassica napus/parasitologia , Interações Hospedeiro-Patógeno , Doenças das Plantas/parasitologia , Plasmodioforídeos/patogenicidade , Brassica napus/citologia , Raízes de Plantas/parasitologia , Plasmodioforídeos/citologia , Plasmodioforídeos/fisiologia , Esporos de Protozoários , Virulência
19.
J Mol Model ; 30(4): 98, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461222

RESUMO

CONTEXT: Various 7H,7'H-[6,6'-bi[1,2,4]triazolo[4,3-b][1,2,4]triazole]-3,3',7,7'-tetramine (A) based nitrogen-rich energetic salts were designed and their properties explored. All energetic salts possess relatively high nitrogen content (> 48%), positive heats of formation (> 429 kJ/mol) and stability owing to a significant contribution from fused backbone. The cationic component shows a very high heat of formation (2516 kJ/mol); therefore, it is highly suitable for enthalpy enhancement in new energetic salts. The cation was paired with the energetic anions nitrate (NO3-), perchlorate (ClO4-), dinitromethanide (CH(NO2)2-), trinitromethanide (C(NO2)3-), nitroamide (NHNO2-), and dinitroamide (N(NO2)2-) to improve oxygen balance and detonation performance. Designed salts show moderate detonation velocities (7.9-8.7 km/s) and pressures (23.8 - 33.1 GPa). The distribution of frontier molecular orbitals, molecular electrostatic surface potentials, QTAIM topological properties, and noncovalent interactions of designed salts were simulated to understand the electronic structures, charge distribution in molecules, hydrogen bonding, and other nonbond interactions. The predicted safety factor (SF) and impact sensitivity (H50) of designed salts suggest their insensitivity to mechanical stimuli. This work explored the 7H,7'H-[6,6'-bi[1,2,4]triazolo[4,3-b][1,2,4]triazole]-3,3',7,7'-tetramine as a suitable cationic component which could be promising and serve exemplarily in energetic materials. METHODS: The optimization and energy calculations of all the designed compounds were carried out at the B3LYP/6-311 + + G(d,p) and M06-2X/def2-TZVPP levels, utilizing the Gaussian software package. The molecular surface electrostatic potential, quantum theory of atoms in molecules (QTAIM), reduced density gradient (RDG), and noncovalent interaction (NCI) analysis were performed by employing Multiwfn software. The EXPLO5 (v 7.01) thermochemical code and PILEM web application were used to predict the detonation properties.

20.
PLoS One ; 19(1): e0296091, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38165912

RESUMO

BACKGROUND: Self-management skills are important for patients with Chronic Obstructive Pulmonary Disease (COPD) who are responsible for their day to day care. Poor self-management behaviours have a significant influence on symptoms, functional impairments and quality of life. Evidence has shown that self-management interventions support patients to respond to changing symptoms and thereby make appropriate decisions regarding their self-management. OBJECTIVE: This study aimed to find out the effect of self-management interventions in patients with COPD in terms of self-management practice, inhaler practice, COPD symptoms burden, functional ability, self-perceived dyspnoea and emotional symptoms. METHODS: Quasi-experimental pre-test post-test design was carried out among patients with COPD attending respiratory units of Chitwan Medical College Teaching Hospital (CMC-TH), Nepal. Convenience sampling technique was used to select the 70 patients with COPD for the study. Baseline data was collected from the participants using (i) Semi-structured interview schedule for socio-demographic and clinical variables, (ii) COPD Self-Management Practice Questionnaire, (iii) Borg Dyspnoea Scale, and (iv) Six Minute Walking Distance (6MWD) Test (v) Pulmonary Function Test (PFT) and (vi) Observation Checklist. Self-management Intervention given was 2 ½ hour sessions per week for 6 weeks along with information booklets distribution. Participants were re-evaluated after 3 months of intervention using same tools. Data analysis was performed using IBMSPSS version 20.0 for window. Wilcoxon signed-rank test was performed to find the effectiveness of the self-management interventions on outcome parameters. RESULTS: Self-management interventions (2 ½ hour session per week for 6 weeks) elicited a statistically significant change on self-management practice (z = -7.215, p<0.001), inhaler practice (DPI practice z = -6.731, p<0.001, MDI practice, z = -1.816, p = 0.005), functional ability (z = -4.243, p<0.001), self-perceived dyspnoea (z = -4.443, p<0.001), COPD symptom burden (z = -7.009, p<0.001) and emotional symptoms (depression, z = -6.856, p<0.001, anxiety, z = -6.675, p<0.001) of patients with COPD. CONCLUSIONS: Self-management intervention acts as powerful equipment to improve self-management practice, COPD symptoms burden, functional ability, self-perceived dyspnoea and emotional symptoms of patients with COPD. Hence, clinician and policy maker need to plan and intervene the rehabilitation program for the patients with COPD to enhance the effectiveness of therapy, self-management practice and general longevity.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Autogestão , Humanos , Qualidade de Vida , Nepal , Doença Pulmonar Obstrutiva Crônica/psicologia , Dispneia/reabilitação
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