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1.
Nanotechnology ; 31(17): 175301, 2020 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-31899906

RESUMEN

Highly efficient broadband absorbing surfaces covering the UV, visible and near-IR regions are of great importance for low-light imaging devices, optical devices and optoelectronic devices. In this work, we demonstrate the fabrication of remarkably efficient absorbing surfaces due to the formation of nanoflower-like cavity structures on a stainless steel (SS304) surface, along with micropatterning in a hierarchical fashion. The fabrication process is carried out using noncontact, programmable, single-step laser irradiation by an inexpensive and robust 532 nm nanosecond laser. The measured specular antireflection properties over a wide spectral region (250-1800 nm) are extremely low, less than 0.5%, over a large range of incident angles and for both orthogonal polarizations. These special hierarchical structures with nanorods, nanoparticles, and nanocavities, completely trap the photon incident on these surfaces due to multiple reflections. These surface structures evolve with time to give better nanostructured features with higher oxygen content on the surfaces, revealed by FESEM elemental analysis, which increases the ability to trap photons. We believe these antireflection surfaces, with high efficiencies and long-term stability, will play a vital role in many modern technological applications.

2.
Nat Prod Res ; 37(10): 1674-1679, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35879820

RESUMEN

This study aimed to assess the antimicrobial activity of endophytic Phyllosticta fallopiae L67 isolated from Aloe vera against diabetic wound microorganisms and characterise their active fraction for biologically important metabolites. The dichloromethane (DCM) extract exhibited the most significant activity with inhibition zones ranging from 11.33 to 38.33 mm. The minimal inhibitory and lethality concentrations of DCM extract ranged from 78.13 to 2500.00 µg/ml and 625.00 to 5000.00 µg/ml, respectively. The extract showed teratogenicity and lethality in the zebrafish model, where peritoneal and hepatic oedema occurred at 62.50 µg/ml, and no abnormality appeared at 31.25 µg/ml. The extract also inhibited more than 82% biofilm formation. Bioassay-guided fractionation on DCM extract yielded 18 fractions and the most active fraction was subjected to UPLC-QTOF-MS/MS analysis. Flavones, stilbenes, flavanonols, isoflavonoids, phenolic glycosides and phenol derivatives were detected. In conclusion, endophytic P. fallopiae possessed bioactive metabolites with significant antimicrobial activity against diabetic wound microorganisms.


Asunto(s)
Aloe , Antiinfecciosos , Diabetes Mellitus , Animales , Espectrometría de Masas en Tándem , Pez Cebra , Antiinfecciosos/farmacología , Extractos Vegetales/farmacología
3.
PLoS One ; 18(6): e0286673, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37276219

RESUMEN

BACKGROUND: The HIV epidemic in Bangladesh is largely being driven by people who inject drugs (PWID) and mainly concentrated in Dhaka city. Intregrated biological and behavioural survey (IBBS) data of 2016 showed that a considerable percentage of the HIV positive PWID had unsafe sex with their female sex partners. Prevalence of HIV, risk behaviorus and vulnerabilities among the female sex partners of the PWID still remain unexplored. METHODS: To measure HIV prevalence, risk behaviours (drugs/injection/sexual) and vulnerabilities (treatment of and knowledge of sexually transmitted infections (STIs) and HIV/uptake of the routine HIV testing and HIV prevention services/physical and sexual violence), a quantitative survey was conducted among 227 female sex partners of the HIV positive PWID in Dhaka city in 2019 by adopting a take-all sampling technique. RESULTS: The median age of participants was 34.0 years. Prevalence of HIV was 16.7% (95% CI: 12.4-22.2). Only 6.8% to 18.7% of the participants used condoms consistently with different male sex partners; only 6.8%cto 18.7% during last year. Seventy five percent (95% CI: 69.2-80.8) had no knowledge on STI symptoms. Self-reported symptoms of STIs were reported by 26% (95% CI: 20.7-32.1) and half sought treatment during last year. Nineteen percent (95% CI: 14.7-25.1) had comprehensive knowledge of HIV. As part of the routine HIV prevention services by the PWID drop-in-centres (DICs), 42.7% (95% CI: 36.4-49.3) of the participants were tested for HIV and knew their result within the last year. One-third never received HIV prevention services. During the last one year preceding the survey, 46% (95% CI: 39.3-52.6) reported been beaten and 20.2% (95% CI: 15.3-26.1) been raped. CONCLUSION: It is urgently necessary to consider the high-risk behaviours and vulnerabilities in designing or to strengthen targeted interventions for female sex partners of the HIV positive PWID in Dhaka city to ensure equality in accessing and utilization of services.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Consumidores de Drogas , Infecciones por VIH , Enfermedades de Transmisión Sexual , Abuso de Sustancias por Vía Intravenosa , Humanos , Masculino , Femenino , Adulto , Infecciones por VIH/epidemiología , Abuso de Sustancias por Vía Intravenosa/complicaciones , Abuso de Sustancias por Vía Intravenosa/epidemiología , Parejas Sexuales , Prevalencia , Bangladesh/epidemiología , Asunción de Riesgos , Enfermedades de Transmisión Sexual/epidemiología
4.
JMIR Hum Factors ; 10: e46678, 2023 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-38085569

RESUMEN

BACKGROUND: Substance use trends are complex; they often rapidly evolve and necessitate an intersectional approach in research, service, and policy making. Current and emerging digital tools related to substance use are promising but also create a range of challenges and opportunities. OBJECTIVE: This paper reports on a backcasting exercise aimed at the development of a roadmap that identifies values, challenges, facilitators, and milestones to achieve optimal use of digital tools in the substance use field by 2030. METHODS: A backcasting exercise method was adopted, wherein the core elements are identifying key values, challenges, facilitators, milestones, cornerstones and a current, desired, and future scenario. A structured approach was used by means of (1) an Open Science Framework page as a web-based collaborative working space and (2) key stakeholders' collaborative engagement during the 2022 Lisbon Addiction Conference. RESULTS: The identified key values were digital rights, evidence-based tools, user-friendliness, accessibility and availability, and person-centeredness. The key challenges identified were ethical funding, regulations, commercialization, best practice models, digital literacy, and access or reach. The key facilitators identified were scientific research, interoperable infrastructure and a culture of innovation, expertise, ethical funding, user-friendly designs, and digital rights and regulations. A range of milestones were identified. The overarching identified cornerstones consisted of creating ethical frameworks, increasing access to digital tools, and continuous trend analysis. CONCLUSIONS: The use of digital tools in the field of substance use is linked to a range of risks and opportunities that need to be managed. The current trajectories of the use of such tools are heavily influenced by large multinational for-profit companies with relatively little involvement of key stakeholders such as people who use drugs, service providers, and researchers. The current funding models are problematic and lack the necessary flexibility associated with best practice business approaches such as lean and agile principles to design and execute customer discovery methods. Accessibility and availability, digital rights, user-friendly design, and person-focused approaches should be at the forefront in the further development of digital tools. Global legislative and technical infrastructures by means of a global action plan and strategy are necessary and should include ethical frameworks, accessibility of digital tools for substance use, and continuous trend analysis as cornerstones.


Asunto(s)
Ejercicio Físico , Trastornos Relacionados con Sustancias , Humanos , Trastornos Relacionados con Sustancias/epidemiología
5.
Zootaxa ; 4732(3): zootaxa.4732.3.6, 2020 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-32230251

RESUMEN

The morphologies of the three freshwater stentorid ciliates in Korea, Stentor coeruleus (Pallas, 1766); Stentor muelleri Ehrenberg, 1831, and Stentor tartari Murthy Bai, 1974, were investigated based on live observations and protargol impregnation. The Korean population of S. tartari exhibits the following characteristics: body size 200-355 × 85-135 µm in vivo, 62-106 somatic kineties, 8-13 peristomial kineties, 110-180 adoral membranelles, mostly two macronuclear nodules and 5-18 micronuclei, reddish and colorless cortical granules and the presence of symbiotic algae. We identified S. tartari based on unique characteristics compared to close congeners. Korean populations of S. coeruleus and S. muelleri are congruent with previously described populations in most aspects of their morphologies. Here, for the first time, we report molecular gene sequence information for S. tartari. Small subunit (SSU) rRNA gene sequence-based phylogeny indicates that S. tartari, which has multiple macronuclei, forms a monophyletic group with other Stentor species having a single macronucleus. Our findings based on morphology and SSU rRNA gene sequence information corroborate the hypothesis that the elongated macronucleus evolved from the compact single or multi macronucleus state.


Asunto(s)
Cilióforos , Animales , China , ADN Protozoario , Filogenia , República de Corea
6.
J Pharm Sci ; 109(9): 2884-2890, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32534882

RESUMEN

Pressure ulcers are commonly associated with microbial infections on the wounds which require an effective wound dressing for treatment. Thus far, the available silver dressing has shown tremendous result, however, it may cause argyria and complicate the internal organ function. Hence, our study aims to develop and characterize phomopsidione-loaded chitosan-polyethylene glycol nanocomposite hydrogel (C/PEG/Ph) as an antimicrobial dressing. Physically, the C/PEG/Ph hydrogel demonstrated a uniform light blue color, soft, flexible, and elastic, with no aggregation form. The evaluation via Fourier Transform Infrared (FTIR) exposed the C/PEG/Ph hydrogel has a notable shift towards lower frequency at 1600 and 1554 cm-1. For drug release test, the phomopsidione attained plateau at 24 h, with a total release of 67.9 ± 6.4% from the C/PEG/Ph hydrogel. There was a null burst release effect discovered throughout the experimental period. The C/PEG/Ph hydrogel showed significant results against all 4 Gram-negative bacteria and 1 yeast, with 99.99-100% reduction of microbial growth. The findings revealed that the C/PEG/Ph hydrogel can potentially act as an antimicrobial dressing for pressure ulcers.


Asunto(s)
Quitosano , Nanocompuestos , Úlcera por Presión , Vendajes , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato , Polietilenglicoles , Úlcera por Presión/tratamiento farmacológico , Cicatrización de Heridas
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