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The COVID-19 pandemic revealed opportunities to improve prevention practices in healthcare settings, mainly related to the spread of airborne microbes (also known as bioaerosols). This scoping review aimed to map methodologies used to assess the implementation of portable air cleaners in healthcare settings, identify gaps, and propose recommendations for future research. The protocol was registered in the Open Science Framework and reported following the checklist provided by the Preferred Reporting Items for Systematic Reviews and Meta-Analysis - an extension for Scoping Reviews (PRISMA-ScR) statement. The search strategy was performed in five databases and one grey literature source. At the last selection phase, 24 articles that fulfilled our inclusion criteria were summarized and disseminated. Of these, 17 studies were conducted between 2020 and 2022; one of them was a protocol of a multicentre randomized controlled trial. The outcomes measured among the studies include airborne microbe counts, airborne particle concentrations, and rate of infections/interventions. The leading healthcare settings assessed were dental clinics (28%), patient's wards (16%), operating rooms (16%), and intensive care units (12%). Most of the devices demonstrated a significant potential to mitigate the impact of bioaerosols. Although some indoor air quality parameters can influence the mechanics of aerosols, only a few studies controlled these parameters in their analyses. Future clinical research should assess the rate of infections through randomized controlled trials with long-term follow-up and large sample sizes to determine the clinical importance of the findings.
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COVID-19 , Humanos , COVID-19/prevención & control , Pandemias/prevención & control , Aerosoles y Gotitas Respiratorias , Atención a la Salud , Instituciones de Salud , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como AsuntoRESUMEN
A photonic connection between turbulence and spin glasses has been recently established both theoretically and experimentally using a random fiber laser as a photonic platform. Besides unveiling this interplay, it links the works of two 2021 Nobel laureates in Physics.
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INTRODUCTION: Nitric oxide (NO) modulates inflammatory reactions, having beneficial or toxic effects depending on the concentration. Its elevation can cause proinflammatory effects amplifying the inflammatory process with the participation of cytokines. Smoking has a negative impact on health and is considered one of the risk factors that influence disease development facilitating inflammatory processes. AIM: To compare the serum concentration of NO and cytokines in smokers at baseline and after 4months of abstinence treatment. METHODS: Blood samples which were collected to obtain the serum, at baseline and after 4months, were stored at -80°C until analysis. NO was measured by the total dose of nitrite determined by the Greiss method. CBA was the used technique to determine the concentration of cytokines in supernatants serum. The initial and final results of NO, TNF-α, IL-1, IL-6, IL-8, IL-10 and IL-12 that remained after 4months treatment were compared. Wilcoxon test was used to compare the data and Spearman test for correlations between NO and other variables. A significance level of p<0.05 was adopted. RESULTS: The analysis of NO observed a significant reduction (p=0.001) of the initial median value of 18.80 (3.55-80.01) µmol/L to 8.10 (2.85-14.97) µmol/L after 4months of treatment. There were no significant differences in cytokines from baseline to the end of treatment. CONCLUSION: The results may not mean harm to the body, but an adaptive process, decreasing the metabolism of abstinents due to the reduction of the use of nicotine.
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Citocinas/sangre , Inflamación/sangre , Óxido Nítrico/sangre , Cese del Hábito de Fumar/métodos , Fumar/sangre , Adulto , Anciano , Biomarcadores/sangre , Femenino , Estudios de Seguimiento , Humanos , Inflamación/etiología , Masculino , Persona de Mediana Edad , Fumar/efectos adversos , Factores de TiempoRESUMEN
Mitoxantrone (MTX) is an antineoplastic agent used to treat several types of cancers and on multiple sclerosis, which shows a high incidence of cardiotoxicity. Still, the underlying mechanisms of MTX cardiotoxicity are poorly understood and the potential toxicity of its metabolites scarcely investigated. Therefore, this work aimed to synthesize the MTX-naphthoquinoxaline metabolite (NAPHT) and to compare its cytotoxicity to the parent compound in 7-day differentiated H9c2 cells using pharmacological relevant concentrations (0.01-5 µM). MTX was more toxic in equivalent concentrations in all cytotoxicity tests performed [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide reduction, neutral red uptake, and lactate dehydrogenase release assays] and times tested (24 and 48 h). Both MTX and NAPHT significantly decreased mitochondrial membrane potential in 7-day differentiated H9c2 cells after a 12-h incubation. However, energetic pathways were affected in a different manner after MTX or NAPHT incubation. ATP increased and lactate levels decreased after a 24-h incubation with MTX, whereas for the same incubation time and concentrations, NAPHT did not cause any significant effect. The increased activity of ATP synthase seems responsible for MTX-induced increases in ATP levels, as oligomycin (an inhibitor of ATP synthase) abrogated this effect on 5 µM MTX-incubated cells. 3-Methyladenine (an autophagy inhibitor) was the only molecule to give a partial protection against the cytotoxicity produced by MTX or NAPHT. To the best of our knowledge, this was the first broad study on NAPHT cardiotoxicity, and it revealed that the parent drug, MTX, caused a higher disruption in the energetic pathways in a cardiac model in vitro, whereas autophagy is involved in the toxicity of both compounds. In conclusion, NAPHT is claimed to largely contribute to MTX-anticancer properties; therefore, this metabolite should be regarded as a good option for a safer anticancer therapy since it is less cardiotoxic than MTX.
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Antineoplásicos/toxicidad , Cardiotoxicidad/etiología , Mitoxantrona/toxicidad , Miocitos Cardíacos/efectos de los fármacos , Adenina/análogos & derivados , Adenina/farmacología , Adenosina Trifosfato/metabolismo , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/metabolismo , Autofagia/efectos de los fármacos , Cardiotoxicidad/patología , Línea Celular , Relación Dosis-Respuesta a Droga , Ácido Láctico/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitoxantrona/administración & dosificación , Mitoxantrona/metabolismo , Miocitos Cardíacos/patología , Quinoxalinas/metabolismo , Quinoxalinas/toxicidad , Ratas , Factores de TiempoRESUMEN
BACKGROUND: Port-Wine Stains (PWS) are vascular malformations of the dermis, whereas hemangiomas are vascular tumors usually present at birth. Early non-invasive diagnosis of the vascular lesion would greatly increase treatment efficiency. We propose to use optical coherence tomography (OCT), a morphological imaging technique, coupled with functional blood-flow Doppler modality. METHODS: We imaged lesions from five patients: one with PWS, four with hemangiomas, using a Thorlabs Swept-Source OCT system at 1325 nm. Additional Doppler images allow for distinguishing blood vessels from empty cavities that appear similar on conventional OCT images. RESULTS: We are able to distinguish between normal skin and vascular lesions. The PWS lesion presents blood vessels of mean diameter 114 µm with a standard deviation of 92 µm, and mean depth 304 µm with a standard deviation of 99 µm. The hemangiomas present blood vessels of mean diameter 39 µm with a standard deviation of 19 µm, and mean depth 298 µm with a standard deviation of 133 µm. CONCLUSION: We show a significant difference between the vascular characteristics of the studied PWS and hemangiomas lesions. We believe that OCT complemented by Doppler OCT could be a promising method for future non-invasive diagnosis and monitoring of some vascular lesions.
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Hemangioma Capilar/diagnóstico por imagen , Imagen Multimodal/métodos , Mancha Vino de Oporto/diagnóstico por imagen , Piel/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Ultrasonografía Doppler/métodos , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
The viability and survival of Lactobacillus acidophilus La5 under in vitro simulated gastrointestinal in probiotic dairy dessert was assessed. In addition, the effects of regular consumption of the dessert (5g/day) on the lipid profile, immune system, and antioxidant/biochemical status of Wistar rats were also evaluated after 2weeks of treatment. Adequate counts of L. acidophilus La-5 were observed regards the viability and gastrointestinal conditions. The probiotic dairy dessert was efficient in reducing the LDL-cholesterol, triacylglycerol and increased the HDL-cholesterol in serum. Aspartate amino transferase, alanine aminotransferase, total protein, albumin, heat shock proteins, immune system responses, and blood-cells counts (monocyte, lymphocyte, neutrophil and leucocyte) were not affected (p>0.05) after 15days of treatment. Overall, the probiotic dairy dessert may be a viable alternative to enhance the blood lipid profile and could be used to improve the antioxidant defenses.
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Metamorphosis in flatfish (Pleuronectiformes) is a late post-embryonic developmental event that prepares the organism for the larval-to-juvenile transition. Thyroid hormones (THs) play a central role in flatfish metamorphosis and the basic elements that constitute the thyroid axis in vertebrates are all present at this stage. The advantage of using flatfish to study the larval-to-juvenile transition is the profound change in external morphology that accompanies metamorphosis making it easy to track progression to climax. This important lifecycle transition is underpinned by molecular, cellular, structural and functional modifications of organs and tissues that prepare larvae for a successful transition to the adult habitat and lifestyle. Understanding the role of THs in the maturation of organs and tissues with diverse functions during metamorphosis is a major challenge. The change in diet that accompanies the transition from a pelagic larvae to a benthic juvenile in flatfish is associated with structural and functional modifications in the gastrointestinal tract (GI-tract). The present review will focus on the maturation of the GI-tract during metamorphosis giving particular attention to organogenesis of the stomach a TH triggered event. Gene transcripts and biological processes that are associated with GI-tract maturation during Atlantic halibut metamorphosis are identified. Gene ontology analysis reveals core biological functions and putative TH-responsive genes that underpin TH-driven metamorphosis of the GI-tract in Atlantic halibut. Deciphering the specific role remains a challenge. Recent advances in characterizing the molecular, structural and functional modifications that accompany the appearance of a functional stomach in Atlantic halibut are considered and future research challenges identified.
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Peces Planos/genética , Tracto Gastrointestinal/inmunología , Metamorfosis Biológica/genética , Hormonas Tiroideas/genética , Animales , Regulación del Desarrollo de la Expresión GénicaRESUMEN
Although the Atlantic halibut (Hippoglossus hippoglossus) is an important commercial species, there is still a deficit with regard to the number of transcripts in the databases, which can be accessed and exploited for targeted candidate gene and pathway studies. In this study, the RNAs from head, skin and GI tract from different developmental stages were sequenced to generate 22,272 contigs of 500 base pairs or greater as a molecular resource for this species.
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Lenguado/genética , Transcriptoma/genética , Animales , Acuicultura , Secuencia de Bases , Cartilla de ADN/genética , Lenguado/crecimiento & desarrollo , Lenguado/metabolismo , Tracto Gastrointestinal/metabolismo , Perfilación de la Expresión Génica , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Piel/metabolismoRESUMEN
Biodegradable materials including biodegradable metals are continuously being investigated for the development of next generation cardiovascular stents. Predictive in vitro tests are needed that could evaluate potential materials while simulating in vivo conditions. In this manuscript we report the microscopic bio-corrosion evaluations of magnesium surfaces in static and dynamic conditions. A corrosion test bench was designed and fabricated and static and dynamic corrosion tests were carried out with samples of magnesium alloy. The fluid wall shear stress equation and the Churchill's friction factor equation were used to calculate the fluid velocity required to generate the desired shear stress on samples in the test bench. Static and dynamic corrosion tests at 24 and 72 h were carried out at 0.88 Pa shear stress mimicking the in vivo shear stress. Microscopic evaluations of the corroded surfaces were carried out by optical, scanning electron microscopy and energy dispersive X-ray spectroscopy to evaluate the corrosion behaviour and surface properties of the test samples. The surface and interface analysis of magnesium samples post test indicated that dynamic conditions prevented the build-up of corrosion by-products on the sample surface and the corrosion mechanism was uniform as compared to static conditions. The use of a masking element to restrict the exposed area of the sample didn't result in increased corrosion at the boundary. Thus, we have demonstrated the feasibility of the designed test bench as a viable method for bio-corrosion surface analysis under dynamic corrosion conditions for potential biodegradable cardiovascular stent materials.
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Materiales Biocompatibles , Magnesio/química , Microscopía Electrónica de Rastreo/métodos , Stents , Corrosión , Resistencia al Corte , Propiedades de SuperficieRESUMEN
Aspartic peptidases are proteolytic enzymes present in many organisms like vertebrates, plants, fungi, protozoa and in some retroviruses such as human immunodeficiency virus (HIV). These enzymes are involved in important metabolic processes in microorganisms/virus and play major roles in infectious diseases. Although few studies have been performed in order to identify and characterize aspartic peptidase in trypanosomatids, which include the etiologic agents of leishmaniasis, Chagas' disease and sleeping sickness, some beneficial properties of aspartic peptidase inhibitors have been described on fundamental biological events of these pathogenic agents. In this context, aspartic peptidase inhibitors (PIs) used in the current chemotherapy against HIV (e.g., amprenavir, indinavir, lopinavir, nelfinavir, ritonavir and saquinavir) were able to inhibit the aspartic peptidase activity produced by different species of Leishmania. Moreover, the treatment of Leishmania promastigotes with HIV PIs induced several perturbations on the parasite homeostasis, including loss of the motility and arrest of proliferation/growth. The HIV PIs also induced an increase in the level of reactive oxygen species and the appearance of irreversible morphological alterations, triggering parasite death pathways such as programed cell death (apoptosis) and uncontrolled autophagy. The blockage of physiological parasite events as well as the induction of death pathways culminated in its incapacity to adhere, survive and escape of phagocytic cells. Collectively, these results support the data showing that parasites treated with HIV PIs have a significant reduction in the ability to cause in vivo infection. Similarly, the treatment of Trypanosoma cruzi cells with pepstatin A showed a significant inhibition on both aspartic peptidase activity and growth as well as promoted several and irreversible morphological changes. These studies indicate that aspartic peptidases can be promising targets in trypanosomatid cells and aspartic proteolytic inhibitors can be benefic chemotherapeutic agents against these human pathogenic microorganisms.
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Proteasas de Ácido Aspártico/antagonistas & inhibidores , Proteínas Protozoarias/antagonistas & inhibidores , Trypanosoma/enzimología , Proteasas de Ácido Aspártico/clasificación , Proteasas de Ácido Aspártico/metabolismo , Inhibidores de la Proteasa del VIH/farmacología , Inhibidores de la Proteasa del VIH/uso terapéutico , Humanos , Nelfinavir/farmacología , Proteínas Protozoarias/metabolismo , Saquinavir/farmacología , Tripanocidas/farmacología , Tripanocidas/uso terapéutico , Trypanosoma/efectos de los fármacos , Trypanosoma/patogenicidad , Tripanosomiasis/tratamiento farmacológico , Tripanosomiasis/parasitologíaRESUMEN
Use of molecular markers can be limited by the high cost and extensive time required for their development. Transfer of simple sequence repeat (SSR) markers reduces the cost and time limitations and has allowed the use of these markers in a larger number of species. We tested 11 SSR markers previously developed for Anacardium occidentale on A. humile. The 11 loci were successfully amplified in A. humile. All loci were polymorphic and generated a mean of 5.4 alleles per locus. The observed heterozygosity was lower than the expected heterozygosity under Hardy-Weinberg equilibrium for most loci, with mean values of 0.463 and 0.696, respectively. The endogamy coefficients were positive and significant for seven loci. However, the combined probability of paternity exclusion was high, and the combined probability of genetic identity was low. None of the pairs of loci were in linkage disequilibrium. The informative power of these loci demonstrates that they are suitable for studies of diversity and genetic structure of natural populations of A. humile. In addition, the loci are suitable for estimating gene flow between populations, assessing species crossing preferences, and performing interspecific comparisons.
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Anacardium/genética , Alelos , Genes de Plantas , Sitios Genéticos , Heterocigoto , Desequilibrio de Ligamiento , Repeticiones de Microsatélite , Polimorfismo Genético , Especificidad de la EspecieRESUMEN
The primary objective of this work was to evaluate the capability of curcumin, a natural compound found in the Curcuma longa plant, to sensitize a clinical isolate of Candida albicans, which was found to have a high resistance to fluconazole. In addition, we assessed whether the resistance of this isolate was the result of the existence of efflux pumps, which could confer a multiple drug resistance phenotype. To evaluate azole resistance, we used the Clinical Laboratory Standard Institute (CLSI) MIC assays procedures with minor modifications. For evaluation of synergistic interaction of curcumin and fluconazole, checkerboard experiments were employed. Nile red and Rhodamine 6G accumulation assays were used to evaluate efflux pump activity. Curcumin was found to have a great capability to inhibit fluconazole resistance of the isolate of C. albicans. It was capable of restoring its sensitivity to this azole when used at 11 µM. Analysis with different azoles and the two indicated dyes showed that an efflux pump could be acting and contributing to the resistance of this isolate to fluconazole. The results suggest that a major facilitator superfamily (MFS) transporter might be involved in this process.
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Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Curcumina/farmacología , Farmacorresistencia Fúngica Múltiple/efectos de los fármacos , Fluconazol/farmacología , Transporte Biológico Activo/efectos de los fármacos , Curcuma/química , Humanos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacologíaRESUMEN
OBJECTIVES: The aim of this paper was to evaluate a transillumination (TI) system using near-infrared (NIR) light and bitewing radiographs for the detection of early approximal enamel caries lesions. METHODS: Mesiodistal sections of teeth (n = 14) were cut with various thicknesses from 1.5 mm to 4.75 mm. Both sides of each section were included, 17 approximal surfaces with natural enamel caries and 11 surfaces considered intact. The approximal surfaces were illuminated by NIR light and X-ray. Captured images were analysed by two calibrated specialists in radiology, and re-analysed after 6 months using stereomicroscope images as a gold standard. RESULTS: The interexaminer reliability (Kappa test statistic) for the NIR TI technique showed moderate agreement on first (0.55) and second (0.48) evaluation, and low agreement for bitewing radiographs on first (0.26) and second (0.32) evaluation. In terms of accuracy, the sensitivity for the NIR TI system was 0.88 and the specificity was 0.72. For the bitewing radiographs the sensitivity ranged from 0.35 to 0.53 and the specificity ranged from 0.50 to 0.72. CONCLUSION: In the same samples and conditions tested, NIR TI images showed reliability and the enamel caries surfaces were better identified than on dental radiographs.
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Caries Dental/diagnóstico , Radiografía de Mordida Lateral , Transiluminación/métodos , Caries Dental/diagnóstico por imagen , Esmalte Dental/patología , Humanos , Rayos Infrarrojos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
An Er(3+)-doped SiO2:Ta2O5 optical channel waveguide and nanocomposite were prepared by the sol-gel route at a Si:Ta 50:50 molar ratio. Channels with an excellent surface profile were easily and quickly fabricated by focusing a femtosecond laser onto the surface of multilayered films deposited on SiO2/Si substrates. In parallel, the same sol used to prepare the film was annealed at 900, 1000, and 1100 degrees C for 2 h, to get the nanocomposite materials. A broadband NIR emission around 1538 nm, assigned to the 4I13/2 --> 4I15/2 transition of the Er3+ ions was observed in the nanocomposites of amorphous SiO2 containing dispersed Ta2O5 nanocrystals. The 4I13/2 lifetime and emission bandwidth depend on the annealing temperature. In conclusion, Er(3+)-doped SiO2:Ta2O5 channel waveguides and nanocomposites are promising materials for photonic applications.
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Cerámica/química , Nanoestructuras/química , Nanotecnología/instrumentación , Refractometría/instrumentación , Resonancia por Plasmón de Superficie/instrumentación , Cristalización/métodos , Diseño de Equipo , Análisis de Falla de Equipo , Rayos Infrarrojos , Nanoestructuras/ultraestructura , Tamaño de la Partícula , Transición de FaseRESUMEN
PURPOSE: Oral mucositis (OM) is a frequent side effect in patients with cancer. We investigate the effect of atorvastatin (ATV), a cholesterol-lowering drug, on OM induced by 5-fluorouracil (5-FU) in hamsters. METHODS: OM was induced by the i.p. administration of 5-FU, with excoriations of the cheek pouch mucosa. The animals were pretreated with i.p. ATV 1, 5 or 10 mg/kg or vehicle (saline and 5% (vol/vol) ethanol) 30 min before 5-FU injection and daily for 5 or 10 days. Samples of cheek pouches and main organs were removed for histopathological analysis, determination of TNF-α, IL-1ß, nitrite, non-protein sulfhydryl group (NP-SH) levels, myeloperoxidase (MPO) assay and immunohistochemistry for induced nitric oxide synthase (iNOS). Blood was collected for a leukogram analysis of biochemical parameters and analysis of bacteremia. RESULTS: ATV at doses of 1 and 5 mg/kg reduced mucosal damage and inflammation, as well as the levels of cytokines, nitrite and myeloperoxidase activity on the 5th and 10th day of OM and immunostaining for iNOS on the 5th day of OM.ATV at 1 mg/kg increased cheek pouch NP-SH when compared to 5-FU groups on the 10th day of OM. The association between ATV 5 mg/kg and 5-FU decreased the survival rate, amplified the leukopenia of animals, increased transaminase serum levels and caused liver lesions. We also detected the presence of Gram-negative bacillus in the blood of 100% of the animals treated with ATV 5 mg/kg + 5-FU. CONCLUSIONS: Atorvastatin prevented mucosal damage and inflammation associated with 5-FU-induced OM, but the association of a higher dose of ATV with 5-FU induced hepatotoxicity and amplified leukopenia.
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Antiinflamatorios no Esteroideos/toxicidad , Antimetabolitos Antineoplásicos/toxicidad , Fluorouracilo/toxicidad , Ácidos Heptanoicos/uso terapéutico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Pirroles/uso terapéutico , Estomatitis/tratamiento farmacológico , Animales , Atorvastatina , Bacteriemia/inducido químicamente , Bacteriemia/microbiología , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Cricetinae , Citocinas/metabolismo , Relación Dosis-Respuesta a Droga , Ácidos Heptanoicos/efectos adversos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Leucopenia/inducido químicamente , Masculino , Mesocricetus , Mucosa Bucal/efectos de los fármacos , Mucosa Bucal/patología , Óxido Nítrico Sintasa de Tipo II/metabolismo , Nitritos/metabolismo , Peroxidasa/metabolismo , Pirroles/efectos adversos , Estomatitis/inducido químicamente , Estomatitis/patología , Compuestos de Sulfhidrilo/metabolismoRESUMEN
We present two new techniques exploiting a Hartmann-Shack wavefront sensor to characterize the optical self-focusing effect of nonlinear materials. We demonstrate that the defocus Zernike coefficient (C5) can be used to quantify nonlinear optical properties of materials. In the first technique proposed, the wavefront of a collimated laser beam transmitted through a nonlinear sample is analyzed with different irradiance values. In the second technique,instead of conventional detectors, a Hartmann- Shack sensor is used in a Z-scan setup. The methods are demonstrated by measuring the nonlinear refractive indices of CS2 and Quartz, using femtosecond Ti:sapphire lasers at 76 MHz and 1 KHz repetition rate.
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Rayos Láser , Óptica y Fotónica , Óxido de Aluminio/química , Diseño de Equipo , Ensayo de Materiales , Dinámicas no Lineales , Dispositivos Ópticos , Titanio/químicaRESUMEN
Ischemic preconditioning (IPC), a strategy used to attenuate ischemia-reperfusion injury, consists of brief ischemic periods, each followed by reperfusion, prior to a sustained ischemic insult. The purpose of the present study was to evaluate the local and systemic anti-inflammatory effects of hind limb IPC in male Wistar rat (200-250 g) models of acute inflammation. IPC was induced with right hind limb ischemia for 10 min by placing an elastic rubber band tourniquet on the proximal part of the limb followed by 30 min of reperfusion. Groups (N = 6-8) were submitted to right or left paw edema (PE) with carrageenan (100 µg) or Dextran (200 µg), hemorrhagic cystitis with ifosfamide (200 mg/kg, ip) or gastric injury (GI) with indomethacin (20 mg/kg, vo). Controls received similar treatments, without IPC (Sham-IPC). PE is reported as variation of paw volume (mL), vesical edema (VE) as vesical wet weight (mg), vascular permeability (VP) with Evans blue extravasation (µg), GI with the gastric lesion index (GLI; total length of all erosions, mm), and neutrophil migration (NM) from myeloperoxidase activity. The statistical significance (P < 0.05) was determined by ANOVA, followed by the Tukey test. Carrageenan or Dextran-induced PE and VP in either paw were reduced by IPC (42-58.7 percent). IPC inhibited VE (38.8 percent) and VP (54 percent) in ifosfamide-induced hemorrhagic cystitis. GI and NM induced by indomethacin were inhibited by IPC (GLI: 90.3 percent; NM: 64 percent). This study shows for the first time that IPC produces local and systemic anti-inflammatory effects in models of acute inflammation other than ischemia-reperfusion injury.
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Animales , Masculino , Ratas , Cistitis/prevención & control , Edema/prevención & control , Miembro Posterior/irrigación sanguínea , Inflamación/prevención & control , Precondicionamiento Isquémico/métodos , Gastropatías/prevención & control , Enfermedad Aguda , Carragenina , Cistitis/inducido químicamente , Edema/inducido químicamente , Ifosfamida , Indometacina , Inflamación/inducido químicamente , Ratas Wistar , Gastropatías/inducido químicamenteRESUMEN
Ischemic preconditioning (IPC), a strategy used to attenuate ischemia-reperfusion injury, consists of brief ischemic periods, each followed by reperfusion, prior to a sustained ischemic insult. The purpose of the present study was to evaluate the local and systemic anti-inflammatory effects of hind limb IPC in male Wistar rat (200-250 g) models of acute inflammation. IPC was induced with right hind limb ischemia for 10 min by placing an elastic rubber band tourniquet on the proximal part of the limb followed by 30 min of reperfusion. Groups (N = 6-8) were submitted to right or left paw edema (PE) with carrageenan (100 microg) or Dextran (200 microg), hemorrhagic cystitis with ifosfamide (200 mg/kg, ip) or gastric injury (GI) with indomethacin (20 mg/kg, vo). Controls received similar treatments, without IPC (Sham-IPC). PE is reported as variation of paw volume (mL), vesical edema (VE) as vesical wet weight (mg), vascular permeability (VP) with Evans blue extravasation (microg), GI with the gastric lesion index (GLI; total length of all erosions, mm), and neutrophil migration (NM) from myeloperoxidase activity. The statistical significance (P < 0.05) was determined by ANOVA, followed by the Tukey test. Carrageenan or Dextran-induced PE and VP in either paw were reduced by IPC (42-58.7%). IPC inhibited VE (38.8%) and VP (54%) in ifosfamide-induced hemorrhagic cystitis. GI and NM induced by indomethacin were inhibited by IPC (GLI: 90.3%; NM: 64%). This study shows for the first time that IPC produces local and systemic anti-inflammatory effects in models of acute inflammation other than ischemia-reperfusion injury.
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Cistitis/prevención & control , Edema/prevención & control , Miembro Posterior/irrigación sanguínea , Inflamación/prevención & control , Precondicionamiento Isquémico/métodos , Gastropatías/prevención & control , Enfermedad Aguda , Animales , Carragenina , Cistitis/inducido químicamente , Edema/inducido químicamente , Ifosfamida , Indometacina , Inflamación/inducido químicamente , Masculino , Ratas , Ratas Wistar , Gastropatías/inducido químicamenteRESUMEN
We have measured and analyzed the behavior of the nonlinear refractive index of silver spheres in water in a non-resonant femtosecond excitation regime. Two different diameter silver nanosphere (0.65 and 9 nm) suspensions were used in the experiments. Thermal and nonthermal contributions to the nonlinear properties of the samples were determined exploring a novel high sensitivity thermal managed eclipse Z-scan technique. The dependence of nonthermal third order nonlinear susceptibility of the colloid with the silver nanoparticles filling factor was described using the generalized Maxwell-Garnett model. The nanoparticle size dependence of the colloid nonlinear refractive index was observed.
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Nanopartículas del Metal/química , Plata/química , Coloides , Dinámicas no Lineales , Refractometría , Análisis Espectral , Temperatura , AguaRESUMEN
In this work we determine the third, fifth- and seventh-order nonresonant nonlinear optical properties of silver nanoparticles (9 nm average diameter) colloids in aqueous solution under high intensity excitation. The nonlinear optical response and its dependence with the nanoparticles filling factor was measured and theoretically described. We show that for low inclusion concentration, the third order nonlinearity of the colloid can be described by the generalized Maxwell-Garnett model. With the increase of the nanoparticle concentration, changes in the medium nonlinearities was observed leading to high order effects. The fifth- and seventh- order susceptibilities were obtained for highly concentrated silver nanoparticle colloid and the data was supported by a theoretical model. The conventional Z-scan technique was employed, using 80 f s laser pulses at 800 nm, in a regime of high pulse energy (microJ) and low repetition rate (1 kHz).