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1.
Molecules ; 26(21)2021 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-34770991

RESUMEN

Photocatalytic nanomaterials, using only light as the source of excitation, have been developed for the breakdown of volatile organic compounds (VOCs) in air for a long time. It is a tough challenge to immobilize these powder photocatalysts and prevent their entrainment with the gas stream. Conventional methods for making stable films typically require expensive deposition equipment and only allow the deposition of very thin layers with limited photocatalytic performance. The present work presents an alternative approach, using the combination of commercially available photocatalytic nanopowders and a polymer or inorganic sol-gel-based matrix. Analysis of the photocatalytic degradation of ethanol was studied for these layers on metallic substrates, proving a difference in photocatalytic activity for different types of stable layers. The sol-gel-based TiO2 layers showed an improved photocatalytic activity of the nanomaterials compared with the polymer TiO2 layers. In addition, the used preparation methods require only a limited amount of photocatalyst, little equipment, and allow easy upscaling.

2.
Biomacromolecules ; 21(6): 1995-2013, 2020 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-32181654

RESUMEN

Bone reconstruction remains an important challenge today in several clinical situations, notably regarding the control of the competition occurring during proliferation of osteoblasts and fibroblasts. Polystyrene and polylactide are reference materials in the biomedical field. Therefore, it could be expected from the literature that clear correlations have been already established between the behavior of fibroblasts or osteoblasts and the surface characteristics of these materials. After an extensive analysis of the literature, although general trends could be established, our critical review has highlighted the need to develop a more in-depth analysis of the surface properties of these materials. Moreover, the large variation noticed in the experimental conditions used for in vitro animal cell studies impairs comparison between studies. From our comprehensive review on this topic, we have suggested several parameters that would be valuable to standardize to integrate the data from the literature and improve our knowledge on the cell-material interactions.


Asunto(s)
Osteoblastos , Poliestirenos , Animales , Línea Celular , Proliferación Celular , Fibroblastos , Poliésteres , Propiedades de Superficie
3.
J Environ Manage ; 250: 109561, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31526963

RESUMEN

The objective of this study was to develop and validate an innovative technology to ensure efficient elimination of different types of micropollutants and toxic compounds in waste water. The process is a tertiary treatment process, which can be easily integrated into municipal and industrial waste water treatment plants. It is based on oxidation by ozone and subsequent photocatalytic treatment. After development and validation of this system at laboratory scale, the solution was tested at pilot scale. The first part of this work was to develop a TiO2-based film on glass substrate, characterize its physico-chemical properties and optimize its composition at laboratory scale to be photoactive on the degradation of model water containing several pollutants. The model water consisted of a mixture of 22 major micropollutants including pesticides, plasticizers, brominated compounds, and pharmaceuticals. The best photocatalyst for the degradation of the selected micropollutants was a TiO2 coating doped with 2 wt% of Ag and where 10 wt% P25 was added. Then, in order to scale up the process, its deposition on steel substrates was tested with dip and spray coating at laboratory scale. Calcination parameters were optimized to limit steel corrosion while keeping similar photoactive properties regarding the degradation of the model polluted water. The optimized solution was deposited by spray coating in a pilot scale reactor in order to assess its efficiency in a pilot water treatment plant.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Catálisis , Oxidación-Reducción , Titanio , Aguas Residuales , Agua
4.
Emerg Infect Dis ; 23(13)2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29155657

RESUMEN

Since 1980, Field Epidemiology Training Programs (FETPs) have trained highly qualified field epidemiologists to work for ministries of health (MOH) around the world. However, the 2013-2015 Ebola epidemic in West Africa, which primarily affected Guinea, Liberia, and Sierra Leone, demonstrated a lack of field epidemiologists at the local levels. Trained epidemiologists at these levels could have detected the Ebola outbreak earlier. In 2015, the US Centers for Disease Control and Prevention (CDC) launched FETP-Frontline, a 3-month field training program targeting local MOH staff in 24 countries to augment local public health capacity. As of December 2016, FETP-Frontline has trained 1,354 graduates in 24 countries. FETP-Frontline enhances global health security by training local public health staff to improve surveillance quality in their jurisdictions, which can be a valuable strategy to strengthen the capacity of countries to more rapidly detect, respond to, and contain public health emergencies at the source.


Asunto(s)
Epidemiología/educación , Vigilancia en Salud Pública/métodos , Salud Pública/educación , Brotes de Enfermedades , Epidemiología/normas , Salud Global , Implementación de Plan de Salud , Humanos , Programas Nacionales de Salud , Evaluación de Resultado en la Atención de Salud , Recursos Humanos
5.
Emerg Infect Dis ; 23(13)2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29155654

RESUMEN

The 2014-2015 epidemic of Ebola virus disease in West Africa primarily affected Guinea, Liberia, and Sierra Leone. Several countries, including Mali, Nigeria, and Senegal, experienced Ebola importations. Realizing the importance of a trained field epidemiology workforce in neighboring countries to respond to Ebola importations, the Centers for Disease Control and Prevention Field Epidemiology Training Program unit implemented the Surveillance Training for Ebola Preparedness (STEP) initiative. STEP was a mentored, competency-based initiative to rapidly build up surveillance capacity along the borders of the at-risk neighboring countries Côte d'Ivoire, Mali, Senegal, and Guinea-Bissau. The target audience was district surveillance officers. STEP was delivered to 185 participants from 72 health units (districts or regions). Timeliness of reporting and the quality of surveillance analyses improved 3 months after training. STEP demonstrated that mentored, competency-based training, where learners attain competencies while delivering essential public health services, can be successfully implemented in an emergency response setting.

6.
Contraception ; 132: 110364, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38218312

RESUMEN

OBJECTIVES: This study aimed to compare effectiveness and safety of cervical preparation with osmotic dilators plus same-day misoprostol or overnight mifepristone prior to dilation and evacuation (D&E). STUDY DESIGN: We conducted a retrospective cohort analysis of 664 patients initiating abortion between 18 and 22 weeks at an ambulatory health center. We abstracted medical record data from two consecutive 12-month periods in 2017 to 2019. All patients received overnight dilators plus: 600 mcg buccal misoprostol 90 minutes before D&E (period 1); 200 mg oral mifepristone at time of dilators (period 2). Our primary outcome was procedure time. We report frequency of patients experiencing any acute complication, defined as unplanned procedure (i.e., reaspiration, cervical laceration repair, uterine balloon tamponade) or hospital transfer and bleeding complications. RESULTS: We observed higher mean procedure time in the mifepristone group (9.7 ± 5.3 minutes vs 7.9 ± 4.4, p = 0.004). After adjusting for race, ethnicity, insurance, body mass index, parity, prior cesarean, prior uterine surgery, gestational age, provider, trainee participation, and long-acting reversible contraception initiation, the difference remained statistically significant (relative change 1.09, 95% CI 1.01, 1.17) but failed to reach our threshold for clinical significance. The use of additional misoprostol was more common in the mifepristone group, but the use of an additional set of dilators was not different between groups. Acute complications occurred at a frequency of 4.1% in misoprostol group and 4.3% in mifepristone group (p = 0.90). CONCLUSIONS: We found procedure time to be longer with adjunctive mifepristone compared to misoprostol; however, this difference is unlikely to be clinically meaningful. Furthermore, the frequency of acute complications was similar between groups. IMPLICATIONS: Overnight mifepristone at the time of cervical dilator placement is a safe and effective alternative to adjuvant same-day misoprostol for cervical preparation prior to D&E and may offer benefits for clinic flow and patient experience.


Asunto(s)
Abortivos no Esteroideos , Misoprostol , Embarazo , Femenino , Humanos , Misoprostol/efectos adversos , Mifepristona , Dilatación , Abortivos no Esteroideos/efectos adversos , Estudios Retrospectivos , Segundo Trimestre del Embarazo
7.
J Biomed Mater Res B Appl Biomater ; 112(1): e35354, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37986690

RESUMEN

The study investigates the rheological properties and protein release capacity of a uniform hydrogel composed of sodium alginate (SA) and poloxamer (P407). The hydrogel is prepared through the sustained release of calcium ions, resulting in a reinforced and homogeneous interpenetrating networks (IPNs) of SA and P407 polymeric chains. By adjusting the amount of crosslink agent, the hydrogel exhibites an adjustable dissolution ratio and adaptable gelling time. Moreover, the composite showed a well-structured network and superior mechanical strength, enabling the sustained release of both calcium ions and Soybean Trypsin Inhibitor (STI) protein, a model of Bone Morphogenic Protein (BMP). Importantly, the protein release kinetic can be tuned based on the SA content in the polymeric blend, highlighting the versatile nature of this hydrogel for drug delivery purposes.


Asunto(s)
Alginatos , Calcio , Preparaciones de Acción Retardada/farmacología , Alginatos/farmacología , Hidrogeles/farmacología , Polímeros , Estabilidad Proteica , Iones
8.
Gels ; 9(4)2023 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-37102887

RESUMEN

Monometallic catalysts based on Fe, Ni and Pd, as well as bimetallic catalysts based on Fe-Pd and based on Ni-Pd supported on silica, were synthesized using a sol-gel cogelation process. These catalysts were tested in chlorobenzene hydrodechlorination at low conversion to consider a differential reactor. In all samples, the cogelation method allowed very small metallic nanoparticles of 2-3 nm to be dispersed inside the silica matrix. Nevertheless, the presence of some large particles of pure Pd was noted. The catalysts had specific surface areas between 100 and 400 m2/g. In view of the catalytic results obtained, the Pd-Ni catalysts are less active than the monometallic Pd catalyst (<6% of conversion) except for catalysts with a low proportion of Ni (9% of conversion) and for reaction temperatures above 240 °C. In this series of catalysts, increasing the Ni content increases the activity but leads to an amplification of the catalyst deactivation phenomenon compared to Pd alone. On the other hand, Pd-Fe catalysts are more active with a double conversion value compared to a Pd monometallic catalyst (13% vs. 6%). The difference in the results obtained for each of the catalysts in the Pd-Fe series could be explained by the greater presence of the Fe-Pd alloy in the catalyst. Fe would have a cooperative effect when associated with Pd. Although Fe is inactive alone for chlorobenzene hydrodechlorination, when Fe is coupled to another metal from the group VIIIb, such as Pd, it allows the phenomenon of Pd poisoning by HCl to be reduced.

9.
Nanomaterials (Basel) ; 12(19)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36234406

RESUMEN

Phthalocyanines (Pcs) are often used in photosensitization of titanium(IV) oxide, a commonly employed photocatalyst, as such an approach holds the promise of obtaining highly stable and efficient visible light-harvesting materials. Herein, we report on the preparation, characterization and photoactivity of a series of composites based on TiO2 and peripherally modified metallophthalocyanines: either tetrasulfonated or 4,4',4'',4'''-tetraazaphthalocyanines, with either copper(II), nickel(II) or zinc(II) as the central metal ion. Physicochemical characterization was performed using UV-Vis diffuse reflectance spectroscopy, hydrodynamic particle-size analysis, surface-area analysis using N2 adsorption-desorption measurements and thermogravimetry combined with differential scanning calorimetry. The band-gap energy values were lower for the composites with peripherally modified phthalocyanines than for the commercial TiO2 P25 or the unsubstituted zinc(II) phthalocyanine-grafted TiO2. TG-DSC results confirmed that the chemical deposition, used for the preparation of Pc/TiO2 composites, is a simple and efficient method for TiO2 surface modification, as all the Pc load was successfully grafted on TiO2. The photocatalytic potential of the Pc/TiO2 materials was assessed in the photocatalytic removal of sulfamethoxazole-a commonly used antibacterial drug of emerging ecological concern. To compare the activity of the materials in different conditions, photodegradation tests were conducted both in water and in an organic medium.

10.
Environ Technol ; 42(25): 3974-3986, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32674725

RESUMEN

A process combining three steps has been developed as a tertiary treatment for waste water in order to remove micropollutants not eliminated by a conventional waste water treatment plant (WWTP). These three processes are ozonation, photocatalysis and granulated activated carbon adsorption. This process has been developed through three scales: laboratory, pilot and pre-industrial scale. At each scale, its efficiency has been assessed on different waste waters: laboratory-made water, industrial waste water (one from a company cleaning textiles and another from a company preparing culture media, both being in continuous production mode) and municipal waste water. At laboratory scale, a TiO2-based photocatalytic coating has been produced and the combination of ozonation-UVC photocatalytic treatment has been evaluated on the laboratory-made water containing 22 micropollutants. The results showed an efficient activity leading to complete or partial degradation of all compounds and an effective carbon for residual micropollutant adsorption was highlighted. Experiments at pilot scale (100 L of water treated at 500 L/h from a tank of 200 L) corroborated the results obtained at laboratory scale. Moreover, tests on municipal waste water showed a decrease in toxicity, measured on Daphnia Magma, and a decrease in micropollutant concentration after treatment. Finally, a pre-industrial container was built and evaluated as a tertiary treatment at the WWTP Duisburg-Vierlinden. It is shown that the main parameters for the efficiency of the process are the flow rate and the light intensity. The photocatalyst plays a role by degrading the more resistant micropollutants. Adsorption permits an overall elimination >95% of all molecules detected.


Asunto(s)
Ozono , Contaminantes Químicos del Agua , Purificación del Agua , Laboratorios , Eliminación de Residuos Líquidos , Aguas Residuales/análisis
11.
Nanomaterials (Basel) ; 9(1)2019 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-30669532

RESUMEN

A screening study on seven photocatalysts was performed to identify the best candidate for pharmaceutical products degradation in water. Photocatalysts were deposited as thin films through a sol-gel process and subsequent dip-coating on glass slides. The efficiency of each photocatalyst was assessed through the degradation of methylene blue first, and then, through the degradation of 15 different pharmaceutical products. Two main types of synthesis methods were considered: aqueous syntheses, where the reaction takes place in water, and organic syntheses, where reactions take place in an organic solvent and only a stoichiometric amount of water is added to the reaction medium. Photocatalysts synthesized via aqueous sol-gel routes showed relatively lower degradation efficiencies; however, the organic route required a calcination step at high temperature to form the photoactive crystalline phase, while the aqueous route did not. The best performances for the degradation of pharmaceuticals arose when Evonik P25 and silver nanoparticles were added to TiO2, which was synthesized using an organic solvent. In the case of methylene blue degradation, TiO2 modified with Evonik P25 and TiO2 doped with MnO2 nanoparticles were the two best candidates.

13.
Dermatopathology (Basel) ; 5(2): 64-68, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29998100

RESUMEN

Cutaneous squamous cell carcinoma (SCC) exhibiting microcystic adnexal carcinoma-like differentiation is an extremely rare tumor that shows both squamous and ductal differentiation. This tumor is often misdiagnosed clinically and histologically and is confused with other malignant and benign cutaneous neoplasms. It usually occurs in middle-aged to older adults. Here, we report a case of SCC with microcystic adnexal carcinoma-like differentiation on the left chin of a 71-year-old male. The histopathological examination revealed a nodular tumor infiltrating the dermis, subcutaneous fat, and striated muscle tissue, consisting of both prominent atypical squamous differentiation and foci of duct-like structures.

14.
Environ Sci Pollut Res Int ; 25(19): 18251-18262, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28500552

RESUMEN

Essential oils from aromatic plants are currently mentioned as suitable tools for excellent protection of stored grains from insect pest attacks. The present work aimed to study the processes of the synthesis insecticidal formulation with clay. The active terpenic compounds of essential oil of Eucalyptus globulus (Eg) were fixed in the palygorskite by adsorption process. Two sample types of palygorskites were used: raw and organo-palygorskite. The palygorskite clays were characterized by different physicochemical techniques including X-ray diffraction (XRD), Fourier transform infrared (FTIR) analyses, thermogravimetric analysis (TG), differential thermal analysis (DTA), Brunauer-Emmet-Teller (BET), and scanning electron microscope (SEM). Results reveal that the raw clay has a fibrous structure with impurities essential calcite. These structures and physicochemical properties of raw palygorskite and organo-palygorskite give it the potential of material adsorbent. Results show that the adsorption capacity strongly depends on affinity between terpenic compounds and organic cations rather than on interlayer distance of organo-palygorskite. The highest adsorption capacity of terpenic compounds is acquired with palygorskite interlaced by didodecyldimethylammonium bromide (DDDMA). These results validated the potential utility of the Paly-DDDMA as adsorbent fibrous clay for the retention of terpenic compounds in application of environmental preservation.


Asunto(s)
Aceite de Eucalipto/química , Compuestos de Magnesio/química , Modelos Teóricos , Compuestos de Silicona/química , Terpenos/química , Adsorción , Cinética , Propiedades de Superficie , Difracción de Rayos X
15.
Materials (Basel) ; 11(4)2018 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-29642626

RESUMEN

In this paper, TiO2 prepared with an aqueous sol-gel synthesis by peptization process is doped with nitrogen precursor to extend its activity towards the visible region. Three N-precursors are used: urea, ethylenediamine and triethylamine. Different molar N/Ti ratios are tested and the synthesis is adapted for each dopant. For urea- and trimethylamine-doped samples, anatase-brookite TiO2 nanoparticles of 6-8 nm are formed, with a specific surface area between 200 and 275 m²·g-1. In ethylenediamine-doped samples, the formation of rutile phase is observed, and TiO2 nanoparticles of 6-8 nm with a specific surface area between 185 and 240 m²·g-1 are obtained. X-ray photoelectron spectroscopy (XPS) and diffuse reflectance measurements show the incorporation of nitrogen in TiO2 materials through Ti-O-N bonds allowing light absorption in the visible region. Photocatalytic tests on the remediation of water polluted with p-nitrophenol show a marked improvement for all doped catalysts under visible light. The optimum doping, taking into account cost, activity and ease of synthesis, is up-scaled to a volume of 5 L and compared to commercial Degussa P25 material. This up-scaled sample shows similar properties compared to the lab-scale sample, i.e., a photoactivity 4 times higher than commercial P25.

16.
Front Surg ; 4: 60, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29075632

RESUMEN

BACKGROUND: Total laryngectomy after (chemo)radiotherapy is associated with a high incidence of fistula and therefore flaps are advocated. The description of a transoral robotic total laryngectomy prompted us to develop similar minimally invasive open approaches for functional total laryngectomy. METHODS: A retrospective study of consecutive unselected patients with a dysfunctional larynx after (chemo)radiation that underwent open maximal mucosal-sparing functional total laryngectomy (MMSTL) between 2014 and 2016 is presented. The surgical technique is described, and the complications and functional outcome are reviewed. RESULTS: The cohorts included 10 patients who underwent open MMSTL. No pedicled flap was used. Only one postoperative fistula was noted (10%). All patients resumed oral diet and experienced a functional tracheo-esophageal voice. CONCLUSION: MMSTL could be used to perform functional total laryngectomy without a robot and with minimal incidence of complications.

17.
Bioresour Technol ; 133: 109-17, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23428815

RESUMEN

This paper investigated the enhancement effect of nanometre-sized metallic (Pd, Ag and Cu) or metallic oxide (FexOy) nanoparticles on fermentative hydrogen production from glucose by a Clostridium butyricum strain. These nanoparticles (NP) of about 2-3 nm were encapsulated in porous silica (SiO2) and were added at very low concentration (10(-6) mol L(-1)) in batch hydrogen production test. The cultures containing iron oxide NP produced 38% more hydrogen with a higher maximum H2 production rate (HPR) of 58% than those without NP or with silica particles only. The iron oxide NP were used in a 2.5L sequencing-batch reactor and showed no significant effect on the yields (established at 2.2 mol(hydrogen) mol(glucose)(-1)) but an improvement of the HPR (+113%, reaching a maximum HPR of 86 mL(hydrogen) L(-1) h(-1)). These results suggest an improvement of the electron transfers trough some combinations between enzymatic activity and inorganic materials.


Asunto(s)
Clostridium butyricum/metabolismo , Fermentación/efectos de los fármacos , Compuestos Férricos/farmacología , Hidrógeno/metabolismo , Nanopartículas del Metal/química , Dióxido de Silicio/farmacología , Anaerobiosis/efectos de los fármacos , Reactores Biológicos/microbiología , Dióxido de Carbono/metabolismo , Catálisis/efectos de los fármacos , Clostridium butyricum/efectos de los fármacos , Porosidad , Solubilidad
18.
Acta Otolaryngol ; 130(7): 820-3, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20082568

RESUMEN

CONCLUSION: The test is simple and sensitive enough to separate normal subjects from patients suffering from a vestibular loss. There was also a good correlation between the objective results and the subjective complaint of oscillopsia. OBJECTIVES: Oscillopsia (i.e. blurred vision while walking) is often reported by patients suffering from vestibular loss. We developed a test to quantify oscillopsia. METHODS: Visual acuity was determined in 16 normal subjects and in 8 patients suffering from a bilateral vestibular loss, at rest and while walking at increasing speed on a treadmill. Snellen optotypes were randomly projected on a screen and the visual acuity was determined with an adaptative staircase algorithm. RESULTS: In normal subjects, the visual acuity did not decrease markedly during walking, but decreased significantly in patients with a vestibular loss.


Asunto(s)
Reflejo Anormal/fisiología , Reflejo Vestibuloocular/fisiología , Enfermedades Vestibulares/fisiopatología , Pruebas de Función Vestibular/métodos , Agudeza Visual/fisiología , Adulto , Anciano , Estudios de Casos y Controles , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas de Visión/métodos , Caminata/fisiología
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