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1.
BJGP Open ; 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38866404

RESUMEN

BACKGROUND: This study evaluates the feasibility of remote deep venous thrombosis (DVT) diagnosis via ultrasound sequences facilitated by ThinkSono Guidance, an artificial intelligence (AI)-app, for point-of-care ultrasound (POCUS). AIM: The aim is to assess the effectiveness of AI-guided POCUS conducted by non-specialists in capturing valid ultrasound images for remote diagnosis of DVT. DESIGN & SETTING: Over a 3.5-month period, patients with suspected DVT underwent AI-guided POCUS conducted by non-specialists using a handheld ultrasound probe connected to the app. These ultrasound sequences were uploaded to a cloud-dashboard for remote specialist review. Additionally, participants received a formal DVT scans. METHOD: Patients underwent AI-guided POCUS using handheld probes connected to the AI-app, followed by formal DVT scans. Ultrasound sequences acquired during the AI-guided scan were uploaded to a cloud-dashboard for remote specialist review, where image quality was assessed, and diagnoses were provided. RESULTS: Among 91 predominantly elderly female participants, 18% of scans were incomplete. Of the rest, 91% had sufficient quality, with 64% categorised by remote clinicians as "compressible" or "incompressible." Sensitivity and specificity for adequately imaged scans were 100% and 91%, respectively. Notably, 53% were low risk, potentially obviating formal scans. CONCLUSION: ThinkSono Guidance effectively directed non-specialists, streamlining DVT diagnosis and treatment. It may reduce the need for formal scans, particularly with negative findings, and extend diagnostic capabilities to primary care. The study highlights AI-assisted POCUS potential in improving DVT assessment.

2.
Health Technol Assess ; 28(24): 1-54, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38768043

RESUMEN

Background: Arteriovenous fistulas are considered the best option for haemodialysis provision, but as many as 30% fail to mature or suffer early failure. Objective: To assess the feasibility of performing a randomised controlled trial that examines whether, by informing early and effective salvage intervention of fistulas that would otherwise fail, Doppler ultrasound surveillance of developing arteriovenous fistulas improves longer-term arteriovenous fistula patency. Design: A prospective multicentre observational cohort study (the 'SONAR' study). Setting: Seventeen haemodialysis centres in the UK. Participants: Consenting adults with end-stage renal disease who were scheduled to have an arteriovenous fistula created. Intervention: Participants underwent Doppler ultrasound surveillance of their arteriovenous fistulas at 2, 4, 6 and 10 weeks after creation, with clinical teams blinded to the ultrasound surveillance findings. Main outcome measures: Fistula maturation at week 10 defined according to ultrasound surveillance parameters of representative venous diameter and blood flow (wrist arteriovenous fistulas: ≥ 4 mm and > 400 ml/minute; elbow arteriovenous fistulas: ≥ 5 mm and > 500 ml/minute). Mixed multivariable logistic regression modelling of the early ultrasound scan data was used to predict arteriovenous fistula non-maturation by 10 weeks and fistula failure at 6 months. Results: A total of 333 arteriovenous fistulas were created during the study window (47.7% wrist, 52.3% elbow). By 2 weeks, 37 (11.1%) arteriovenous fistulas had failed (thrombosed), but by 10 weeks, 219 of 333 (65.8%) of created arteriovenous fistulas had reached maturity (60.4% wrist, 67.2% elbow). Persistently lower flow rates and venous diameters were observed in those fistulas that did not mature. Models for arteriovenous fistulas' non-maturation could be optimally constructed using the week 4 scan data, with fistula venous diameter and flow rate the most significant variables in explaining wrist fistula maturity failure (positive predictive value 60.6%, 95% confidence interval 43.9% to 77.3%), whereas resistance index and flow rate were most significant for elbow arteriovenous fistulas (positive predictive value 66.7%, 95% confidence interval 48.9% to 84.4%). In contrast to non-maturation, both models predicted fistula maturation much more reliably [negative predictive values of 95.4% (95% confidence interval 91.0% to 99.8%) and 95.6% (95% confidence interval 91.8% to 99.4%) for wrist and elbow, respectively]. Additional follow-up and modelling on a subset (n = 192) of the original SONAR cohort (the SONAR-12M study) revealed the rates of primary, assisted primary and secondary patency arteriovenous fistulas at 6 months were 76.5, 80.7 and 83.3, respectively. Fistula vein size, flow rate and resistance index could identify primary patency failure at 6 months, with similar predictive power as for 10-week arteriovenous fistula maturity failure, but with wide confidence intervals for wrist (positive predictive value 72.7%, 95% confidence interval 46.4% to 99.0%) and elbow (positive predictive value 57.1%, 95% confidence interval 20.5% to 93.8%). These models, moreover, performed poorly at identifying assisted primary and secondary patency failure, likely because a subset of those arteriovenous fistulas identified on ultrasound surveillance as at risk underwent subsequent successful salvage intervention without recourse to early ultrasound data. Conclusions: Although early ultrasound can predict fistula maturation and longer-term patency very effectively, it was only moderately good at identifying those fistulas likely to remain immature or to fail within 6 months. Allied to the better- than-expected fistula patency rates achieved (that are further improved by successful salvage), we estimate that a randomised controlled trial comparing early ultrasound-guided intervention against standard care would require at least 1300 fistulas and would achieve only minimal patient benefit. Trial Registration: This trial is registered as ISRCTN36033877 and ISRCTN17399438. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: NIHR135572) and is published in full in Health Technology Assessment; Vol. 28, No. 24. See the NIHR Funding and Awards website for further award information.


For people with advanced kidney disease, haemodialysis is best provided by an 'arteriovenous fistula', which is created surgically by joining a vein onto an artery at the wrist or elbow. However, these take about 2 months to develop fully ('mature'), and as many as 3 out of 10 fail to do so. We asked whether we could use early ultrasound scanning of the fistula to identify those that are unlikely to mature. This would allow us to decide whether it would be practical to run a large, randomised trial to find out if using early ultrasound allows us to 'rescue' fistulas that would otherwise fail. We invited adults to undergo serial ultrasound scanning of their fistula in the first few weeks after it was created. We then analysed whether we could use the data from the early scans to identify those fistulas that were not going to mature by week 10. Of the 333 fistulas that were created, about two-thirds reached maturity by week 10. We found that an ultrasound scan 4 weeks after fistula creation could reliably identify those fistulas that were going to mature. However, of those fistulas predicted to fail, about one-third did eventually mature without further intervention, and even without knowing what the early scans showed, another third were successfully rescued by surgery or X-ray-guided treatment at a later stage. Performing an early ultrasound scan on a fistula can provide reassurance that it will mature and deliver trouble-free dialysis. However, because scans are poor at identifying fistulas that are unlikely to mature, we would not recommend their use to justify early surgery or X-ray-guided treatment in the expectation that this will improve outcomes.


Asunto(s)
Derivación Arteriovenosa Quirúrgica , Fallo Renal Crónico , Diálisis Renal , Ultrasonografía Doppler , Grado de Desobstrucción Vascular , Humanos , Femenino , Masculino , Persona de Mediana Edad , Derivación Arteriovenosa Quirúrgica/efectos adversos , Estudios Prospectivos , Fallo Renal Crónico/terapia , Anciano , Reino Unido , Adulto
3.
Kidney Int Rep ; 9(4): 1005-1019, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38765580

RESUMEN

Introduction: We assess if ultrasound surveillance of newly-created arteriovenous fistulas (AVFs) can predict nonmaturation sufficiently reliably to justify randomized controlled trial (RCT) evaluation of ultrasound-directed salvage intervention. Methods: Consenting adults underwent blinded fortnightly ultrasound scanning of their AVF after creation, with scan characteristics that predicted AVF nonmaturation identified by logistic regression modeling. Results: Of 333 AVFs created, 65.8% matured by 10 weeks. Serial scanning revealed that maturation occurred rapidly, whereas consistently lower fistula flow rates and venous diameters were observed in those that did not mature. Wrist and elbow AVF nonmaturation could be optimally modeled from week 4 ultrasound parameters alone, but with only moderate positive predictive values (PPVs) (wrist, 60.6% [95% confidence interval, CI: 43.9-77.3]; elbow, 66.7% [48.9-84.4]). Moreover, 40 (70.2%) of the 57 AVFs that thrombosed by week 10 had already failed by the week 4 scan, thus limiting the potential of salvage procedures initiated by that scan's findings to alter overall maturation rates. Modeling of the early ultrasound characteristics could also predict primary patency failure at 6 months; however, that model performed poorly at predicting assisted primary failure (those AVFs that failed despite a salvage attempt), partly because patency of at-risk AVFs was maintained by successful salvage performed without recourse to the early scan data. Conclusion: Early ultrasound surveillance may predict fistula maturation, but is likely, at best, to result in only very modest improvements in fistula patency. Power calculations suggest that an impractically large number of participants (>1700) would be required for formal RCT evaluation.

4.
Acta Radiol ; 64(11): 2931-2937, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37722861

RESUMEN

BACKGROUND: Tomographic 3D ultrasound (t3DUS) is a promise imaging technique for quantifying carotid plaque through measuring the degree of stenosis and plaque volume. Carotid plaque volume (CPV) could add benefit in predicting the potential risk of stroke. PURPOSE: To assess the reproducibility and accuracy of t3DUS for measuring CPV within the internal carotid artery in patients undergoing carotid endarterectomy. MATERIAL AND METHODS: t3DUS was used to obtain CPV in vivo from 25 symptomatic patients prior to surgery. Ex vivo CPV from the carotid endarterectomy specimen was then measured using a validated saline displacement method as a reference standard. CPV for each patient was measured twice using both methods (total n = 50 per technique). Intraclass correlation coefficient (ICC) and Bland-Altman plot were used to establish bias and limit of agreement between CPV measurements. RESULTS: There was an excellent agreement between t3DUS and reference test with respect to measuring CPV with an ICC value of 0.98 (95% confidence interval = 0.97-0.99, P < 0.001). Bias in measurements was 0.02 ± 0.11 cm3 (95% limit of agreement = -0.19 to 0.25). Intra-observer agreement of t3DUS CPV measurements was excellent with an ICC value of 0.95 (95% confidence interval = 0.92-0.97, P < 0.001). Bias in measurements was 0.004 ± 0.07 cm3 (95% limit of agreement = -0.14 to 0.15). CONCLUSION: t3DUS is a reproducible imaging method and showed excellent agreement with the reference standard with respect to measuring CPV. These findings suggest that t3DUS has the potential to be a valuable non-invasive tool for assessing carotid plaque burden and predicting the risk of stroke.


Asunto(s)
Estenosis Carotídea , Placa Aterosclerótica , Accidente Cerebrovascular , Humanos , Arteria Carótida Interna/diagnóstico por imagen , Reproducibilidad de los Resultados , Estenosis Carotídea/diagnóstico por imagen , Placa Aterosclerótica/diagnóstico por imagen , Arterias Carótidas
5.
Materials (Basel) ; 16(12)2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37374424

RESUMEN

The nonlinear ultrasonic evaluation technique is useful for assessing micro-defects and microstructure changes caused by fatigue or bending damage. In particular, the guided wave is advantageous for long-distance testing such as piping and plate. Despite these advantages, the study of nonlinear guided wave propagation has received relatively less attention compared to bulk wave techniques. Furthermore, there is a lack of research on the correlation between nonlinear parameters and material properties. In this study, the relationship between nonlinear parameters and plastic deformation resulting from bending damage was experimentally investigated using Lamb waves. The findings indicated an increase in the nonlinear parameter for the specimen, which was loaded within the elastic limit. Inversely, regions of maximum deflection in specimens with plastic deformation exhibited a decrease in the nonlinear parameter. This research is expected to be helpful for maintenance technology in the nuclear power plant and aerospace fields that require high reliability and accuracy.

6.
Perfusion ; : 2676591231169852, 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37068210

RESUMEN

INTRODUCTION: Treatment decision of lower extremity peripheral arterial disease (PAD) is governed by the severity of stenosis. Tomographic 3D ultrasound (t3DUS) is a reliable imaging technique for measuring vessel stenosis. In this study we attempted to provide a precise measurement of superficial femoral artery (SFA) stenosis using t3DUS in patients with PAD. METHODS: t3DUS was used to measure maximum stenosis percentage in SFA from 50 patients with lower extremity PAD. The maximum stenosed segment in SFA was defined using Duplex 2DUS aliasing was noted. The peak systolic velocity (PSV) was measured at the maximum stenotic site and proximal to aliasing for calculating the velocity ratio. The association between blood flow velocity ratio and the degree of stenosis measured using Duplex 2DUS and t3DUS, respectively, was assessed using Spearman rank correlation. RESULTS: There was a strong positive correlation between velocity ratio and degree of stenosis in SFA measured using t3DUS (correlation value (r) = 0.99, p < 0.001). The correlation between Stenosis percentage and velocity ratio in SFA are as followed: <50:<2; 50-54:2-2.4; 55-59:2.5-2.9; 60-64:3-3.4; 65-69:3.5-3.9; 70-74:4-4.4; 75-79:4.5-4.9; >80:>5.t3DUS can be used to provide precise measurement of the severity of SFA stenosis in patients with lower extremities arterial disease. The established criteria for grading SFA stenosis in this study can be applied to the current practice alongside Duplex 2DUS as it showed a strong positive correlation with velocity ratio. Further studies investigating the sensitivity and specificity of t3DUS in the assessment of stenosis in lower limbs arteries are required.

7.
Atmos Pollut Res ; 13(10): 101566, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36187213

RESUMEN

The characteristics of black carbon (BC) aerosols, their sources, and their impact on atmospheric radiative forcing were extensively studied during the COVID-19 lockdown (28th March-31st May 2020) at a high-altitude rural site over the Western Ghats in southwest India. BC concentration and the contribution of BC originating from biomass burning (BCbb) estimated from the aethalometer model during the lockdown period were compared with the same periods in 2017 and 2018 and with the pre-lockdown period (1st February to March 20, 2020). BC concentrations were 44, 19, and 17% lower during the lockdown period compared with the pre-lockdown periods of 2020 and similar periods (28th March to 31st May) of 2017 and 2018, respectively. BCbb contributed ∼50% to total BC during the lockdown period of 2020 and compensated for the decrease in BC concentration due to lower traffic emissions. The characteristics of light-absorbing organic carbon (brown carbon; BrC) absorption at 370 nm were evaluated during the lockdown and the pre-lockdown periods of 2020, 2017, and 2018. The BrC was estimated to be the highest during the lockdown period of 2020. Finally, atmospheric radiative forcing was calculated using the mean BC concentration during the pre-lockdown, lockdown, and similar periods (28th March to 31st May) of 2017 and 2018.

8.
Molecules ; 27(17)2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-36080358

RESUMEN

This study reports a facile approach for preparing low-cost, eco-friendly nanocomposites of ZnO nanoparticles (NPs) and date palm tree fiber (DPF) as a biomass sorbent. The hypothesis of this research work is the formation of an outstanding adsorbent based on the date palm fiber and ZnO nanoparticles. ZnO NP/DPF nanocomposites were synthesized by mixing the synthesized ZnO NPs and DPF in different mass ratios and evaluating their efficacy in adsorbing Pb2+ from aqueous solutions. The structure and surface morphology of the developed ZnO NP/DPF nanocomposite were critically characterized by XRD, FESEM, and TEM techniques. Compared to ZnO NPs, the ZnO NP/DPF nanocomposites displayed significantly enhanced Pb2+ uptake. Pb2+ adsorption was confirmed via various isotherm and kinetic models and thermodynamics. The computed Langmuir sorption capacity (qm) was found to be 88.76 mg/g (R2 > 0.998), and the pseudo-second-order R2 > 0.999 model was most appropriate for describing Pb2+ adsorption. Impregnating the biomass with ZnO NPs enhanced the spontaneity of the process, and the value (−56.55 kJ/mol) of ΔH displayed the exothermic characteristics of Pb2+ retention. Only the loaded ZnO NP/DPF achieved the removal of a high percentage (84.92%) of Pb2+ from the environmental water sample (seawater). This finding suggests the use of ZnO NP/DPF nanocomposites for removing heavy metals from environmental water samples to purify the samples.


Asunto(s)
Nanocompuestos , Phoeniceae , Contaminantes Químicos del Agua , Óxido de Zinc , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Plomo , Nanocompuestos/química , Termodinámica , Agua/química , Contaminantes Químicos del Agua/química , Óxido de Zinc/química
9.
Ultrasound Med Biol ; 48(9): 1899-1906, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35715330

RESUMEN

The aim of this phantom study was to assess the accuracy of 3-D tomographic ultrasound (t3DUS) for grading stenosis, using the manufacturer's measurements as the gold standard. The percentage of maximum stenosis was obtained using 2-D ultrasound (2DUS) and t3DUS imaging techniques on a peripheral vascular phantom, including channels with 50%, 75% and 90% stenosis. The inter-observer reproducibility of t3DUS for grading stenosis was assessed using the intraclass correlation coefficient (ICC) and Bland-Altman plots. Mean and mean differences were used to evaluate the accuracy of 2DUS and t3DUS in measuring maximum stenosis in all channels. Inter-operator agreement was excellent, with an ICC value of 0.99 (95% confidence interval: 0.994-0.998, p < 0.001). Bias in measurements was -0.59 ± 2.01% (95% limits of agreement: 4.54, 3.36). The mean difference (MD) between maximum stenosis measurements and reference values for all channels was lower in t3DUS than in 2DUS (t3DUS MD: +1.01%, diameter reduction 2DUS MD: -6.10%; area reduction 2DUS MD: +8.20%). Tomographic 3DUS is a reproducible and accurate imaging method for grading stenosis. The current B-mode 2DUS stenosis grading criteria used in vascular assessment may be underestimating or overestimating the percentage stenosis. Further phantom and human studies investigating the reliability of t3DUS for grading stenosis and other metrics including plaque volume are required.


Asunto(s)
Placa Aterosclerótica , Constricción Patológica , Humanos , Imagenología Tridimensional/métodos , Variaciones Dependientes del Observador , Fantasmas de Imagen , Reproducibilidad de los Resultados , Ultrasonografía/métodos
10.
CNS Neurol Disord Drug Targets ; 21(10): 952-965, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34967302

RESUMEN

Significant efforts have been made in research to discover newer neurotherapeutics, however, the rate of reported neurological disorders has been increasing at an alarming speed. Neurotherapeutics delivery in the brain is still posing a significant challenge, owing to the blood-brain barrier and blood-cerebrospinal fluid barrier. These physiological barriers restrict the passage of systemically available fractions of neurotherapeutics into the brain, owing to low permeability and drug localization factors. Neurotherapeutics encapsulating lipid carriers favor a significant increase in bioavailability of poorly water-soluble drugs by enhancing solubility in the gastrointestinal tract and favoring stability. Due to their small size and lipid-based composition, these carriers offer enhanced permeability across the semi-permeable blood-brain barrier to effectively transport encapsulated loads, such as synthetic drugs, nutraceuticals, phytoconstituents, herbal extracts, and peptides, thereby reducing incidences of off-target mediated adverse impacts and toxicity. The most significant advantage of such lipid-based delivery systems is non-invasive nature and targeting of neurotherapeutics to the central nervous system. Critical attributes of lipid-based carriers modulate release rates in rate-controlled manners, enable higher penetration through the blood-brain barrier, and bypass the hepatic first-pass metabolism leading to higher CNS bioavailability neurotherapeutics. The current review discusses a brief and introductory account of the limitations of neurotherapeutics, pharmacological barriers, challenges in brain-targeted delivery, and the potential of nanotechnology- processed lipid-based carriers in the clinical management of neuronal disorders.


Asunto(s)
Barrera Hematoencefálica , Nanopartículas , Barrera Hematoencefálica/metabolismo , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Portadores de Fármacos/farmacología , Sistemas de Liberación de Medicamentos , Lípidos/farmacología , Nanopartículas/química , Nanotecnología
11.
Ann Surg ; 276(5): e605-e612, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-33630461

RESUMEN

OBJECTIVE: We compared the diagnostic performance of a novel point-of-care duplex ultrasound test (podiatry ankle duplex scan; PAD-scan) against commonly used bedside tests for the detection of PAD in diabetes. BACKGROUND: PAD is a major risk factor for diabetic foot ulceration and amputation. Its diagnosis is fundamental though challenging. Although a variety of bedside tests are available, there is no agreement as to which is the most useful. PAD-scan may be advantageous over current tests as it allows for vessel visualization and more accurate arterial waveform assessment. However, its accuracy has not been previously evaluated. METHODS: From March to October 2019, we recruited 305 patients from 2 diabetic foot clinics. The diagnostic performance of ankle-brachial pressure index, toe-brachial pressure index, transcutaneous pressure of oxygen, pulse palpation, and ankle waveform assessment using PAD-scan and Doppler devices (audible and visual waveform assessment) were assessed. The reference test was a full lower limb duplex ultrasound. RESULTS: Based on the reference test, 202 (66.2%) patients had evidence of PAD. PAD-scan had a significantly higher sensitivity [95%, confidence interval (CI) 90%-97%) as compared to all other tests. Particularly low sensitivities were seen with pulse palpation (43%, CI 36%-50%) and transcutaneous pressure of oxygen (31%, CI 24%-38%). PAD-scan had a lower specificity (77%, CI 67%-84%) compared to toe-brachial pressure index (86%, CI 78%-93%; P < 0.001), but not statistically different when compared to all other tests. CONCLUSIONS: PAD-scan has superior diagnostic utility and is a valid first line investigation.


Asunto(s)
Diabetes Mellitus , Pie Diabético , Enfermedad Arterial Periférica , Índice Tobillo Braquial/efectos adversos , Pie Diabético/complicaciones , Pie Diabético/diagnóstico , Humanos , Oxígeno , Pruebas en el Punto de Atención
12.
Anticancer Agents Med Chem ; 22(4): 654-667, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33992067

RESUMEN

BACKGROUND: Chemo- and radiation therapy-based clinical management of different types of cancers is associated with toxicity and several side effects. Therefore, there is always an unmet need to explore agents that reduce such risk factors. Among these, natural products have attracted much attention because of their potent antioxidant and antitumor effects. In the past, some breakthrough outcomes established that various bacteria in the human intestinal gut are bearing growth-promoting attributes and suppressing the conversion of pro-carcinogens into carcinogens. Hence probiotics integrated approaches are nowadays being explored as rationalized therapeutics in the clinical management of cancer. METHODS: Here, published literature was explored to review chemoprotective roles of probiotics against toxic and side effects of chemotherapeutics. RESULTS: Apart from excellent anti-cancer abilities, probiotics alleviate toxicity & side effects of chemotherapeutics, with a high degree of safety and efficiency. CONCLUSION: Preclinical and clinical evidence suggests that due to the chemoprotective roles of probiotics against side effects and toxicity of chemotherapeutics, their integration in chemotherapy would be a judicious approach.


Asunto(s)
Neoplasias , Probióticos , Bifidobacterium , Carcinógenos/farmacología , Humanos , Lactobacillus , Neoplasias/tratamiento farmacológico , Probióticos/farmacología
13.
Restor Dent Endod ; 46(4): e58, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34909422

RESUMEN

OBJECTIVES: This study addresses the effect of using nanoparticles (np) on the antimicrobial properties of bioactive glass (BAG) when used in intracanal medicaments against Enterococcus faecalis (E. faecalis) biofilms. MATERIALS AND METHODS: E. faecalis biofilms, grown inside 90 root canals for 21 days, were randomly divided into 4 groups according to the antimicrobial regimen followed (n = 20; BAG-np, BAG, calcium hydroxide [CaOH], and saline). After 1 week, residual live bacteria were quantified in terms of colony-forming units (CFU), while dead bacteria were assessed with a confocal laser scanning microscope. RESULTS: Although there was a statistically significant decrease in the mean CFU value among all groups, the nano-group performed the best. The highest percentage of dead bacteria was detected in the BAG-np group, with a significant difference from the BAG group. CONCLUSIONS: The reduction of particle size and use of a nano-form of BAG improved the antimicrobial properties of the intracanal treatment of E. faecalis biofilms.

14.
Adv Mater ; 33(21): e2008668, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33837605

RESUMEN

The evolution of polygonal-shaped nanoholes on the (100) surface of germanium, aided by focused ion beam induced self-organization, is presented. The energetic beam of ions creates a viscous phase which, at a thermodynamical minimum, leads to surface self-organization. A directed viscous-flow along the predefined nanoholes provides well-ordered polygonal nanostructures, ranging from triangles to hexagons and octagons, as desired. The amorphization exhibiting a confined viscous-flow at the walls of nanoholes is attributed to the localized melting zones induced by site-specific thermal spikes during ion irradiation, as revealed by microscopy and molecular dynamics studies. This leads to a local self-organization in the vicinity of each circular nanohole via a viscous-fingering process at the nanoscale. Such controlled self-organization, with the help of a predefined scanning grid, transforms the circular holes into the desired polygonal shape. The present morphology manipulation promises to surmount the barriers concerning the size reduction efforts in the field of nanofabrication.

15.
Environ Sci Pollut Res Int ; 28(26): 35266-35277, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33666849

RESUMEN

The temporal variability of the planetary boundary layer height (PBLH) over Mahabaleshwar was studied for a period of 1 year from 1 December 2015 to 30 November 2016 using microwave radiometer (MWR) observations. The PBLH over Mahabaleshwar was found to be the highest during the pre-monsoon (March-May) season and lowest during the winter (December-February) season. The seasonal mean of PBLH was estimated to be 339±88 m during winter, 485±70 m during pre-monsoon, 99±153 m during monsoon, and 438±24 m during post-monsoon season. Frequency distribution analysis of PBLH during pre-monsoon season revealed that the formation of turbulence internal boundary layer (TIBL) is evident. In contrast, cold and moist air mass during the monsoon season enhances the wind shear with lower buoyancy term which results in lowering of PBLH. The comparison of PBLH between MWR and radiosonde observations shows a good correlation (r2 = 0.66, p=0.001). The growth rate was observed to be 388 m/h during pre-monsoon, 206 m/h during winter, 57 m/h during monsoon, and 167 m/h during post-monsoon season. The seasonal mean concentration of PM2.5 was found to be 42.3±4.6 µg/m3during winter, 33.4±8.7 µg/m3 during pre-monsoon, 6.6±2.2 µg/m3 during monsoon, and 26.1±1.7 µg/m3during post-monsoon season. The effect of higher loading of scattering-type aerosol (dust particle) was also investigated as a case study. The analysis reveals the inverse relationship between the PBL height variability and the particulate loading indicating the importance of aerosol direct effect. Analysis of the ventilation coefficient (Vc) revealed that the dissipation potential was higher (1736 m2/s) during pre-monsoon season as compared to (1191 m2/s, 455m2/s, and 1580 m2/s) winter, monsoon, and post-monsoon seasons.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Altitud , Monitoreo del Ambiente , India , Material Particulado/análisis , Estaciones del Año
16.
Perfusion ; 36(7): 751-756, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32957822

RESUMEN

OBJECTIVE: We assessed the association between (1) severity of vessel wall calcification, (2) number of patent vessels at the ankle and (3) arterial spectral waveform features, as assessed on a focused ankle Duplex ultrasound (DUS), and healing at 12-months in a cohort of patients who had their diabetic foot ulcers conservatively managed. RESEARCH DESIGN AND METHODS: Scans performed on 50 limbs in 48 patients were included for analysis. Patient health records were prospectively reviewed for 12-months to assess for the outcome of ulcer healing. RESULTS: We identified that the number of waveform components, peak systolic velocity, systolic rise time and long forward flow as well as the number of vessels patent at the ankle on DUS, may be useful independent predictors of healing, as noted by the trend towards statistical significance. CONCLUSION: Arterial spectral waveform features may be useful in predicting the chance of diabetic foot ulcer healing.


Asunto(s)
Diabetes Mellitus , Pie Diabético , Arterias , Estudios de Cohortes , Humanos , Ultrasonografía Doppler Dúplex , Cicatrización de Heridas
17.
J Infect Dis ; 224(Supple 5): S558-S567, 2021 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-35238363

RESUMEN

BACKGROUND: An earlier cohort in 1995-1996 showed a very high burden of typhoid in Delhi. Our aim was to estimate the current overall and age-specific incidence of culture-confirmed enteric fever among children aged 6 months to 15 years in Delhi. METHODS: We enrolled a cohort of 6000 children aged 6 months to <14 years in South Delhi and followed them up weekly for 24 months or until 15 completed years of child age, whichever was earlier. Blood culture to confirm enteric fever was done in children with ≥3 consecutive days of fever. RESULTS: We recorded a total of 14 650 episodes of fever in the 11 510 person-years (PY) of follow-up. A total of 81 fever episodes were positive for enteric fever. The incidence (95% confidence interval) of all enteric fever was 703.7 (560.5-874.7) per 100 000 PY. The incidences of typhoid and paratyphoid fevers were 608.1 (95% confidence interval, 481.1-768.7) and 111.7 (59.5-191.1) per 100 000 PY, respectively, highest among children aged 10-15 years. CONCLUSIONS: Despite a 35% reduction in incidence compared with the 1995-1996 cohort, our study suggested a substantial burden of enteric fever in the population. Continued efforts to improve water, sanitation, and hygiene parameters along with implementation of novel vaccination strategies and disease surveillance can help achieve the goal of disease elimination.


Asunto(s)
Fiebre Paratifoidea , Fiebre Tifoidea , Vacunas Tifoides-Paratifoides , Adolescente , Niño , Estudios de Cohortes , Fiebre , Humanos , Incidencia , India/epidemiología , Fiebre Paratifoidea/epidemiología , Salmonella typhi , Fiebre Tifoidea/epidemiología
18.
J Liposome Res ; 31(4): 381-388, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33183121

RESUMEN

The aim of the current study was to develop the phytosomal gel of aloe vera extract for improved topical delivery. Aloe vera extract loaded phytosomal system was developed by fixing the amount of aloe vera extract and ethanol and by varying the concentration of lecithin (0.15-0.25% w/v) and speed of rotation (80-120 rpm). Different formulation batches were prepared as per the Design expert software. A 22 Factorial design was applied to optimize the formulation on the basis of vesicular size and entrapment efficiency. Developed formulations were evaluated for vesicular size, entrapment efficiency, PDI, zeta potential and in-vitro release. Further stability studies were also performed. For the optimized formulation (F09), vesicular size, entrapment efficiency and PDI were found as 123.1 ± 1.44 nm, 95.67 ± 0.27% and 0.98 ± 0.06. Zeta potential of -11.9 mV and drug release of 56.91 ± 4.1% obtained in 24 h. Drug release kinetics from the phytosomes follows Higuchi model. TEM micrograph confirms the uniform structure of phytosomes. Phytosomal gel of optimized phytosomal formulation (F09) was developed with 1% Carbopol 934 and physically characterized on the basis of pH, viscosity, homogeneity and drug content. Ex-vivo permeation study showed the better permeation and flux profile of phytosomal gel with the conventional aloe vera extract gel. Also, studies on phytosomal formulation and gel showed stability up-to 3 months. Thus overall, it can be concluded that the phytosomal gel is a good carrier for topical delivery of herbal extract such as aloe vera.


Asunto(s)
Aloe , Liberación de Fármacos , Liposomas , Extractos Vegetales , Viscosidad
19.
Curr Drug Metab ; 2020 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-32723268

RESUMEN

The article has been withdrawn at the request of the editor of the journal Current Drug Metabolism due to incoherent content. Bentham Science apologizes to the readers of the journal for any inconvenience this may have caused. The Bentham Editorial Policy on Article Withdrawal can be found at https://benthamscience.com/editorial-policies-main.php. Bentham Science Disclaimer: It is a condition of publication that manuscripts submitted to this journal have not been published and will not be simultaneously submitted or published elsewhere. Furthermore, any data, illustration, structure or table that has been published elsewhere must be reported, and copyright permission for reproduction must be obtained. Plagiarism is strictly forbidden, and by submitting the article for publication the authors agree that the publishers have the legal right to take appropriate action against the authors, if plagiarism or fabricated information is discovered. By submitting a manuscript, the authors agree that the copyright of their article is transferred to the publishers if and when the article is accepted for publication.

20.
BMJ Open ; 10(2): e033753, 2020 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-32029491

RESUMEN

INTRODUCTION: In the UK, over 7000 amputations are performed each year because of diabetes. Up to 80% of these are preceded by a foot ulcer and could therefore be prevented with improvements in ulcer care. Peripheral arterial disease is an important risk factor for the development of diabetic foot ulceration. However, its diagnosis in diabetes is challenging due to the presence of neuropathy and arterial calcification. Commonly used bedside tests either have low sensitivities or little supporting evidence to justify their use. Duplex ultrasound (DUS) has good correlation to angiography findings but a full scan is difficult to learn and time consuming to perform. We have previously demonstrated that a focused DUS of the distal anterior and posterior tibial arteries at the ankle (podiatry ankle duplex scan (PAD-scan)) can be readily learnt by novices and performed rapidly and accurately. The primary aim of this study is to determine the diagnostic accuracy of the PAD-scan and other commonly used bedside tests in detecting arterial disease in diabetes. METHODS AND ANALYSIS: The study will include 305 patients presenting to diabetic foot clinics at two centres. Arterial assessment will be performed using the following index tests: the PAD-scan, pulse palpation, audible handheld Doppler, Ankle Brachial Pressure Index, Toe Brachial Pressure Index and transcutaneous pressure of oxygen. Patients will then undergo a full lower limb arterial DUS by a blinded vascular scientist as a reference test. ETHICS AND DISSEMINATION: Approval was gained from NRES Committee London (REC reference 17/LO/1447). Findings will be disseminated by various methods including international presentations and publication in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT04058626).


Asunto(s)
Pie Diabético/diagnóstico por imagen , Pruebas en el Punto de Atención/estadística & datos numéricos , Proyectos de Investigación , Ultrasonografía Doppler Dúplex/métodos , Índice Tobillo Braquial , Humanos , Londres , Reproducibilidad de los Resultados , Ultrasonografía Doppler Dúplex/instrumentación
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