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1.
Glob Chang Biol ; 29(21): 6040-6065, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37605971

RESUMEN

Insect and disease outbreaks in forests are biotic disturbances that can profoundly alter ecosystem dynamics. In many parts of the world, these disturbance regimes are intensifying as the climate changes and shifts the distribution of species and biomes. As a result, key forest ecosystem services, such as carbon sequestration, regulation of water flows, wood production, protection of soils, and the conservation of biodiversity, could be increasingly compromised. Despite the relevance of these detrimental effects, there are currently no spatially detailed databases that record insect and disease disturbances on forests at the pan-European scale. Here, we present the new Database of European Forest Insect and Disease Disturbances (DEFID2). It comprises over 650,000 harmonized georeferenced records, mapped as polygons or points, of insects and disease disturbances that occurred between 1963 and 2021 in European forests. The records currently span eight different countries and were acquired through diverse methods (e.g., ground surveys, remote sensing techniques). The records in DEFID2 are described by a set of qualitative attributes, including severity and patterns of damage symptoms, agents, host tree species, climate-driven trigger factors, silvicultural practices, and eventual sanitary interventions. They are further complemented with a satellite-based quantitative characterization of the affected forest areas based on Landsat Normalized Burn Ratio time series, and damage metrics derived from them using the LandTrendr spectral-temporal segmentation algorithm (including onset, duration, magnitude, and rate of the disturbance), and possible interactions with windthrow and wildfire events. The DEFID2 database is a novel resource for many large-scale applications dealing with biotic disturbances. It offers a unique contribution to design networks of experiments, improve our understanding of ecological processes underlying biotic forest disturbances, monitor their dynamics, and enhance their representation in land-climate models. Further data sharing is encouraged to extend and improve the DEFID2 database continuously. The database is freely available at https://jeodpp.jrc.ec.europa.eu/ftp/jrc-opendata/FOREST/DISTURBANCES/DEFID2/.

2.
Eur Arch Otorhinolaryngol ; 280(4): 2007-2016, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36449093

RESUMEN

BACKGROUND AND AIM: Minimally invasive endoscopic techniques are the treatment of choice for Zenker's diverticulum (ZD). Our objective was to evaluate the results and efficacy of endoscopic and open approaches, to determine whether postoperative C-reactive protein (CRP) serum levels can be used as a marker to exclude the presence of esophageal leakage, and to identify risk factors for development of postoperative leakage and complications. MATERIALS AND METHODS: Patients who underwent transcervical myotomy and diverticulotomy (TMD) or endoscopic cricopharyngeal myotomy (ECM) with CO2 laser for ZD in years 2008-2021 at our department were included in this retrospective study. RESULTS: Of the 101 patients enrolled, 83 patients underwent ECM and 18 TMD. The procedure time of the endoscopic technique was significantly shorter compared to that of transcervical method (p < 0.001). The median time to oral intake was 6 days for ECM and 10.5 days in the TMD group (p < 0.001). There was a 13% (n = 11) and 16.7% (n = 3) symptomatic recurrence rate and 3.6% (n = 3) and 16.7% (n = 3) major complications rate for ECM and TMD groups, respectively. The incidence of contrast leak (CL) evaluated by postoperative swallow study was 8.9% (9 from 83 patients in the ECM group only). In patients with CL, a significant increase in CRP levels on postoperative day (POD) 2 and 3 was detected when compared to patients without CL. CONCLUSIONS: Endoscopic diverticulotomy with CO2 laser represents a safe and efficient treatment of ZD. Elevation of postoperative CRP serum levels over 123.8 mg/L on POD2 and 98.8 mg/L on POD3 may indicate presence of an esophageal leakage.


Asunto(s)
Láseres de Gas , Divertículo de Zenker , Humanos , Esofagoscopía/métodos , Proteína C-Reactiva , Estudios Retrospectivos , Dióxido de Carbono , Láseres de Gas/uso terapéutico , Divertículo de Zenker/cirugía , Resultado del Tratamiento
3.
JAMA Otolaryngol Head Neck Surg ; 148(7): 654-661, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35653138

RESUMEN

Importance: Recurrent respiratory papillomatosis (RRP) is a rare benign chronic disease of the larynx etiologically linked with the infection of low-risk human papillomavirus (HPV). Combination of surgical and immunomodulatory therapy has limited success. Possible use of prophylactic HPV vaccine that includes HPV-6 and HPV-11 antigens has been studied. Objective: To evaluate if the HPV vaccination is associated with a lower number of recurrences requiring surgical intervention in patients with new and recurrent RRP. Design, Setting, and Participants: This was a non-placebo-controlled intervention study. Enrollment data were collected from October 2011 to August 2013. The patients were followed up at 1 month, 12 months, and 5 years after the third dose of the vaccine and clinically monitored until December 31, 2018. Data were analyzed from 2019 to 2021. Altogether, 50 adults with active RRP were enrolled and followed up in referral centers. For the final outcome, follow-up data for 42 patients were available. Eight patients who did not fulfill the protocol were excluded. Interventions: All patients received HPV vaccine as an adjuvant treatment and were clinically followed up. When RRP progression or a significant recurrent lesion was detected, surgical removal via direct laryngoscopy was indicated. No adjuvant therapy with antiviral or biological agents was used. Main Outcomes and Measures: This study compared the prevaccination and postvaccination positivity for HPV-specific antibodies. The main outcome was the difference in the frequency of RRP recurrences in the prevaccination and postvaccination period. Results: A total of 50 patients with RRP were enrolled (median [SD] age, 41.5 [12.3] years [range, 21-73 years]; 39 [78%] men and 11 [22%] women). After HPV vaccination, patients with previously no HPV-specific antibodies showed seroconversion, and all patients developed 100-fold higher levels of HPV vaccine type-specific antibodies compared with the prevaccination period. In patients with recurrent RRP, decreased frequency of recurrences requiring surgical treatment was present after vaccination (from 0.85 to 0.36 recurrences/y). No difference in postvaccination recurrences was found between patients with newly diagnosed and recurrent RRP. Conclusions and Relevance: In this nonrandomized clinical trial, the frequency of RRP recurrences was significantly lower after HPV vaccination, and patients with RRP thus had a reduced burden of disease. Because no difference was detected in the frequency of recurrent postvaccination lesions in patients with new and recurrent disease, it appears that both groups showed equal benefit following HPV vaccination. These findings suggest that the earlier that patients with RRP receive HPV vaccine, the sooner they may show reduced burden of disease. Trial Registration: EudraCT Identifier: 2011-002667-14; ClinicalTrials.gov Identifier: NCT01375868.


Asunto(s)
Alphapapillomavirus , Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Infecciones del Sistema Respiratorio , Adulto , Femenino , Humanos , Masculino , Infecciones por Papillomavirus/prevención & control , Infecciones del Sistema Respiratorio/prevención & control , Vacunación
4.
Biomedicines ; 11(1)2022 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-36672540

RESUMEN

Vestibular schwannoma is the most common benign neoplasm of the cerebellopontine angle. It arises from Schwann cells of the vestibular nerve. The first symptoms of vestibular schwannoma include hearing loss, tinnitus, and vestibular symptoms. In the event of further growth, cerebellar and brainstem symptoms, along with palsy of the adjacent cranial nerves, may be present. Although hearing impairment is present in 95% of patients diagnosed with vestibular schwannoma, most tumors do not progress in size or have low growth rates. However, the clinical picture has unpredictable dynamics, and there are currently no reliable predictors of the tumor's behavior. The etiology of the hearing loss in patients with vestibular schwannoma is unclear. Given the presence of hearing loss in patients with non-growing tumors, a purely mechanistic approach is insufficient. A possible explanation for this may be that the function of the auditory system may be affected by the paracrine activity of the tumor. Moreover, initiation of the development and growth progression of vestibular schwannomas is not yet clearly understood. Biallelic loss of the NF2 gene does not explain the occurrence in all patients; therefore, detection of gene expression abnormalities in cases of progressive growth is required. As in other areas of cancer research, the tumor microenvironment is coming to the forefront, also in vestibular schwannomas. In the paradigm of the tumor microenvironment, the stroma of the tumor actively influences the tumor's behavior. However, research in the area of vestibular schwannomas is at an early stage. Thus, knowledge of the molecular mechanisms of tumorigenesis and interactions between cells present within the tumor is crucial for the diagnosis, prediction of tumor behavior, and targeted therapeutic interventions. In this review, we provide an overview of the current knowledge in the field of molecular biology and tumor microenvironment of vestibular schwannomas, as well as their relationship to tumor growth and hearing loss.

5.
Environ Pollut ; 265(Pt B): 114352, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32806435

RESUMEN

Scots pine (Pinus sylvestris L.) is a widespread tolerant forest tree-species; however, its adaptability to environmental change differs among sites with various buffering capacity. In this study, we compared the spatial effects of aridity index (AI) and nitrogen deposition (ND) on biomass density in natural and man-made pine stands of differing soil fertility using geographically weighted multiple lag regression. Soil fertility was defined using soil series as zonal trophic (27.9%), acidic (48.2%), gleyed (15.2%) and as azonal exposed (2.5%), maple (2.4%), ash (0.8%), wet (2.1%) and peat (0.9%) under pine stands in the Czech Republic (Central Europe; 4290.5 km2; 130-1298 m a.s.l.). Annual AI and ND in every pine stand were estimated by intersection between raster and vector from 1 × 1 km grid for years 2000, 2003, 2007 and 2010 of severe non-specific forest damage spread. Biomass density was obtained from a MODIS 250 × 250 m raster using the enhanced vegetation index (EVI) for years 2000-2015, with a decrease in EVI indicating non-specific damage. Environmental change was assessed by comparing predictor values at EVI time t and t+λ. Non-specific damage was registered over 51.9% of total forest area. Less than 8.8% of damaged stands were natural and the rest (91.2%) of damaged stands were man-made. Pure pine stands were more damaged than mixed. The ND effect prevailed up to 2007, while AI dominated later. Temporal increasing ND effect under AI effectiveness led to the most significant pine stand damage in 2008 and 2014. Predictors from 2000 to 2007 afflicted 58.5% of non-specifically damaged stands at R2 0.09-0.76 (median 0.38), but from 2000 to 2010 afflicted 57.1% of the stands at R2 0.16-0.75 (median 0.40). The most damaged stands occurred on acidic sites. Mixed forest and sustainable management on natural sites seem as effective remediation reducing damage by ND.


Asunto(s)
Pinus sylvestris , Pinus , República Checa , Europa (Continente) , Nitrógeno
6.
Lasers Surg Med ; 52(4): 333-340, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31385332

RESUMEN

BACKGROUND AND OBJECTIVES: Transoral laser surgery is the optimal surgical treatment modality for the early stages of glottic cancer. To allow for further treatment to be as effective and as minimal as possible, persistent or recurrent tumors should be detected very soon. The main aim is to minimize the risk of necessity of performing a total laryngectomy. Flexible videoendoscopy with narrow band imaging (NBI) was recommended by the European Laryngological Society as a diagnostic method for the follow-up of patients treated for laryngeal cancer. Nevertheless, the efficacy of this technique has not been extensively studied in patients after transoral laser cordectomies for vocal fold cancer. The aim of this study was to evaluate the efficacy of in-office transnasal NBI flexible videoendoscopy in the follow-up of patients after transoral laser cordectomy for glottic cancer. We also focused on describing the specific characteristics of recurrent tumor appearance. MATERIALS AND METHODS: The presented study was conceived as a prospective study. Ninety-four consecutive patients who underwent transoral laser cordectomy for severe dysplasia, Tis, T1, and T2 glottic cancer in the period from June 2010 to August 2015 were enrolled in the study. All patients were postoperatively regularly followed using transnasal videoendoscopic examinations with NBI. Whenever a suspect lesion was identified during in-office examination, its nature was proven histologically. RESULTS: We discovered 23 suspect findings in 21 patients by means of flexible videoendoscopy with NBI. Fifteen (65.2%) of them were histologically confirmed as recurrent tumors, whereas in 8 (34.8%) of them, the recurrent tumor was not proven. In two patients, the recurrent tumor was evident on computed tomography or magnetic resonance imaging, but NBI endoscopy did not reveal relapsing disease. The rest (71 patients) were considered true negative. Of the 15 recurrent tumors detected by NBI-coupled videoendoscopy, 8 (53.3%) were identified as submucosal masses with nonsignificant or no vascular changes, 4 (26.7%) were noted as the progression of leukoplakia without visible vascular changes, only 2 (13.3%) showed typical vascular changes, and, in 1 (6.7%) case, evident, significantly exophytic tumor with pathological vascularization was discovered. The sensitivity, specificity, and positive and negative predictive values of the in-office transnasal videolaryngoscopy with NBI were calculated to be 88%, 92%, 71%, and 97%, respectively. CONCLUSIONS: The results of the study demonstrate that transnasal endoscopy with NBI in an outpatient setting is an excellent method for the follow-up of patients after transoral laser cordectomy for glottic cancer. The method achieves high sensitivity, specificity, and negative predictive value and a slightly low positive predictive value. Nevertheless, we must bear in mind that recurrent tumors after previous endoscopic resection may have a completely different appearance than new tumors originating from previously untreated tissues. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.


Asunto(s)
Neoplasias Laríngeas/cirugía , Laringectomía , Terapia por Láser , Imagen de Banda Estrecha , Cirugía Endoscópica por Orificios Naturales , Recurrencia Local de Neoplasia/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Glotis , Humanos , Neoplasias Laríngeas/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos
7.
Phys Chem Chem Phys ; 21(17): 8883-8896, 2019 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-30982833

RESUMEN

Qualitative detection of peroxynitrite/peroxynitrous acid (ONOO-/ONOOH) as one of the key bactericidal agents produced in cold air plasma activated aqueous solutions is presented. We examined the use of the 2,7-dichlorodihydrofluorescein diacetate (H2DCFDA) fluorescent dye to detect ONOO-/ONOOH in plasma activated non-buffered water (PAW) or buffered solution (PAPB) generated by DC-driven self-pulsed transient spark discharge at atmospheric pressure in ambient air. The diagnostic selectivity of H2DCFDA to reactive oxygen and nitrogen species (RONS) typical of plasma activated aqueous solutions was examined by using various scavengers of RONS. This cross-reactivity study showed the highest sensitivity of the H2DCFDA dye to ONOO-/ONOOH. However, besides ONOO-/ONOOH, H2DCFDA also exhibited sensitivity to hypochlorite anions/hypochlorous acid (OCl-/HOCl), showing that for a selective study it is important to have an idea about the possible constituents in the studied solutions. The sensitivity of H2DCFDA to other RONS even in much higher concentrations was negligible. The presence of nitrites (NO2-) and hydrogen peroxide (H2O2) in PAW led predominantly to the production of peroxynitrous acid with a strong fluorescence response of H2DCFDA in PAW. Plasma treatment of buffered solutions led to the weak response of H2DCFDA. The fluorescence induced in PAW decreased after scavenging individual reactants, namely NO2- and H2O2, as well as by scavenging the product of the peroxynitrite forming reaction, proving that the fluorescence response of H2DCFDA is primarily due to the formation of ONOO-/ONOOH. A chemical kinetics analysis of post-discharge processes and the pseudo-second order reaction between H2O2 and NO2- confirms formation of peroxynitrous acid in PAW with a rate in the order of tens of nM per second. The post-discharge evolution of the ONOOH formation rate was clearly correlated with the parallel detection of ONOO-/ONOOH by fluorescence spectroscopy using the H2DCFDA dye.


Asunto(s)
Colorantes Fluorescentes/química , Ácido Peroxinitroso/química , Gases em Plasma/química , Fluoresceínas/química , Peróxido de Hidrógeno/química , Ácido Hipocloroso/química , Cinética , Nitritos/química , Oxidación-Reducción , Especies de Nitrógeno Reactivo/química , Especies Reactivas de Oxígeno/química , Espectrometría de Fluorescencia/métodos , Agua/química
8.
Surv Geophys ; 40: 631-656, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-36081835

RESUMEN

Imaging spectroscopy of vegetation requires methods for scaling and generalizing optical signals that are reflected, transmitted and emitted in the solar wavelength domain from single leaves and observed at the level of canopies by proximal sensing, airborne and satellite spectroradiometers. The upscaling embedded in imaging spectroscopy retrievals and validations of plant biochemical and structural traits is challenged by natural variability and measurement uncertainties. Sources of the leaf-to-canopy upscaling variability and uncertainties are reviewed with respect to: (1) implementation of retrieval algorithms and (2) their parameterization and validation of quantitative products through in situ field measurements. The challenges are outlined and discussed for empirical and physical leaf and canopy radiative transfer modelling components, considering both forward and inverse modes. Discussion on optical remote sensing validation schemes includes also description of a multiscale validation concept and its advantages. Impacts of intraspecific and interspecific variability on collected field and laboratory measurements of leaf biochemical traits and optical properties are demonstrated for selected plant species, and field measurement uncertainty sources are listed and discussed specifically for foliar pigments and canopy leaf area index. The review concludes with the main findings and suggestions as how to reduce uncertainties and include variability in scaling vegetation imaging spectroscopy signals and functional traits of single leaves up to observations of whole canopies.

9.
Cas Lek Cesk ; 156(4): 192-196, 2017.
Artículo en Checo | MEDLINE | ID: mdl-28862009

RESUMEN

Endoscopic optical imaging methods for the detection of mucosal lesions in the ENT area have been developed for better and earlier detection of these changes. They can be divided into horizontal methods group - showing the surface of the mucous membrane (autofluorescence, photodynamic diagnosis, Narrow Band Imaging, magnifying and contact endoscopy) and vertical methods group - visualizing different layers of the mucosa (optical coherence tomography and confocal endomicroscopy). Some of them are routinely used in practice, others are used in experimental mode and their introduction into practice may be a matter of the near future. The authors present a comprehensive overview of available endoscopic optical imaging methods.


Asunto(s)
Endoscopía , Neoplasias Laríngeas , Imagen Óptica , Humanos , Neoplasias Laríngeas/diagnóstico , Imagen de Banda Estrecha
10.
Sensors (Basel) ; 16(11)2016 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-27801818

RESUMEN

Laboratory spectroscopy in visible and infrared regions is an important tool for studies dealing with plant ecophysiology and early recognition of plant stress due to changing environmental conditions. Leaf optical properties are typically acquired with a spectroradiometer coupled with an integration sphere (IS) in a laboratory or with a contact probe (CP), which has the advantage of operating flexibility and the provision of repetitive in-situ reflectance measurements. Experiments comparing reflectance spectra measured with different devices and device settings are rarely reported in literature. Thus, in our study we focused on a comparison of spectra collected with two ISs on identical samples ranging from a Spectralon and coloured papers as reference standards to vegetation samples with broadleaved (Nicotiana Rustica L.) and coniferous (Picea abies L. Karst.) leaf types. First, statistical measures such as mean absolute difference, median of differences, standard deviation and paired-sample t-test were applied in order to evaluate differences between collected reflectance values. The possibility of linear transformation between spectra was also tested. Moreover, correlation between normalised differential indexes (NDI) derived for each device and all combinations of wavelengths between 450 nm and 1800 nm were assessed. Finally, relationships between laboratory measured leaf compounds (total chlorophyll, carotenoids and water content), NDI and selected spectral indices often used in remote sensing were studied. The results showed differences between spectra acquired with different devices. While differences were negligible in the case of the Spectralon and they were possible to be modelled with a linear transformation in the case of coloured papers, the spectra collected with the CP and the ISs differed significantly in the case of vegetation samples. Regarding the spectral indices calculated from the reflectance data collected with the three devices, their mean values were in the range of the corresponding standard deviations in the case of broadleaved leaf type. Larger differences in optical leaf properties of spruce needles collected with the CP and ISs are implicated from the different measurement procedure due to needle-like leaf where shoots with spatially oriented needles were measured with the CP and individual needles with the IS. The study shows that a direct comparison between the spectra collected with two devices is not advisable as spectrally dependent offsets may likely exist. We propose that the future studies shall focus on standardisation of measurement procedures so that open access spectral libraries could serve as a reliable input for modelling of optical properties on a leaf level.


Asunto(s)
Nicotiana/química , Picea/química , Espectrofotometría/métodos , Carotenoides/química , Clorofila/química , Picea/metabolismo , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Espectrofotometría Infrarroja , Nicotiana/metabolismo , Agua/química
11.
In Vivo ; 30(3): 237-42, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27107081

RESUMEN

BACKGROUND: In reoperation of femoral prostheses, there is a higher percentage of complications associated with the extraction of bone cement from the femoral channel, which is technically and time consumingly tedious. Shockwaves have been used in medicine for years, particularly in urology for the destruction of concretions and orthopaedics, as a method of treating pain in patients with calcifying enthesopathy. MATERIALS AND METHODS: We studied the use of shockwaves generated by a new source based on the multichannel discharge principle in facilitating extraction of bone cement. Femurs of experimental minipigs were chosen as models. We implanted bone cement into the femoral channel and subsequently applied shockwaves. We then measured the force necessary to extract bone cement. RESULTS: The results indicate that the force necessary for extracting cement was consistently statistically significantly lower in the group treated with multichannel discharge shockwaves compared to that for the controls.


Asunto(s)
Cementos para Huesos , Huesos , Fémur/cirugía , Ondas de Choque de Alta Energía , Animales , Humanos , Modelos Animales , Prótesis e Implantes , Reoperación/métodos , Porcinos , Porcinos Enanos
12.
Langmuir ; 32(5): 1405-9, 2016 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-26752107

RESUMEN

Controlling microdischarges in plasma electrolytic oxidation is of great importance in order to optimize coating quality. The present study highlights the relationship between the polarity at which breakdown occurs and the electrolyte pH as compared with the isoelectric point (IEP). It is found that working at a pH higher than the IEP of the grown oxide prevents the buildup of detrimental cathodic discharges. The addition of phosphates results in a shift in the IEP to a lower value and therefore promotes anodic discharges at the expense of cathodic ones.

13.
Water Res ; 84: 127-35, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-26218466

RESUMEN

Anthropogenic pollutants and in particular pharmaceutical residues are a potential risk for potable water where they are found in increasing concentrations. Different environmental effects could already be linked to the presence of pharmaceuticals in surface waters even for low concentrations. Many pharmaceuticals withstand conventional water treatment technologies. Consequently, there is a need for new water purification techniques. Advanced oxidation processes (AOP), and especially plasmas with their ability to create reactive species directly in water, may offer a promising solution. We developed a plasma reactor with a coaxial geometry to generate large volume corona discharges directly in water and investigated the degradation of seven recalcitrant pharmaceuticals (carbamazepine, diatrizoate, diazepam, diclofenac, ibuprofen, 17α-ethinylestradiol, trimethoprim). For most substances we observed decomposition rates from 45% to 99% for treatment times of 15-66 min. Especially ethinylestradiol and diclofenac were readily decomposed. As an inherent advantage of the method, we found no acidification and only an insignificant increase in nitrate/nitrite concentrations below legal limits for the treatment. Studies on the basic plasma chemical processes for the model system of phenol showed that the degradation is primarily caused by hydroxyl radicals.


Asunto(s)
Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Carbamazepina/química , Diatrizoato/química , Diazepam/química , Diclofenaco/química , Monitoreo del Ambiente , Etinilestradiol/química , Ibuprofeno/química
14.
Bioelectrochemistry ; 103: 7-14, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25212700

RESUMEN

Electrical discharge plasmas can efficiently inactivate various microorganisms. Inactivation mechanisms caused by plasma, however, are not fully understood because of the complexity of both the plasma and biological systems. We investigated plasma-induced inactivation of Escherichia coli in water and mechanisms by which plasma affects bacterial cell membrane integrity. Atmospheric pressure argon plasma jet generated at ambient air in direct contact with bacterial suspension was used as a plasma source. We determined significantly lower counts of E. coli after treatment by plasma when they were assayed using a conventional cultivation technique than using a fluorescence-based LIVE/DEAD staining method, which indicated that bacteria may have entered the viable-but-nonculturable state (VBNC). We did not achieve resuscitation of these non-culturable cells, however, we detected their metabolic activity through the analysis of cellular mRNA, which suggests that cells may have been rather in the active-but-nonculturable state (ABNC). We hypothesize that peroxidation of cell membrane lipids by the reactive species produced by plasma was an important pathway of bacterial inactivation. Amount of malondialdehyde and membrane permeability of E. coli to propidium iodide increased with increasing bacterial inactivation by plasma. Membrane damage was also demonstrated by detection of free DNA in plasma-treated water.


Asunto(s)
Técnicas Bacteriológicas , Escherichia coli/citología , Gases em Plasma , Presión Atmosférica , Técnicas Bacteriológicas/instrumentación , Técnicas Bacteriológicas/métodos , Permeabilidad de la Membrana Celular , Pared Celular/metabolismo , Desinfección/métodos , Diseño de Equipo , Escherichia coli/efectos de los fármacos , Escherichia coli/fisiología , Peroxidación de Lípido , Propidio/farmacología , Especies Reactivas de Oxígeno/metabolismo
15.
Bioelectrochemistry ; 103: 103-10, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25200989

RESUMEN

Shock waves can cause significant cytotoxic effects in tumor cells and tissues both in vitro and in vivo. However, understanding the mechanisms of shock wave interaction with tissues is limited. We have studied in vivo effects of focused shock waves induced in the syngeneic sarcoma tumor model using the TUNEL assay, immunohistochemical detection of caspase-3 and hematoxylin-eosin staining. Shock waves were produced by a multichannel pulsed-electrohydraulic discharge generator with a cylindrical ceramic-coated electrode. In tumors treated with shock waves, a large area of damaged tissue was detected which was clearly differentiated from intact tissue. Localization and a cone-shaped region of tissue damage visualized by TUNEL reaction apparently correlated with the conical shape and direction of shock wave propagation determined by high-speed shadowgraphy. A strong TUNEL reaction of nuclei and nucleus fragments in tissue exposed to shock waves suggested apoptosis in this destroyed tumor area. However, specificity of the TUNEL technique to apoptotic cells is ambiguous and other apoptotic markers (caspase-3) that we used in our study did not confirmed this observation. Thus, the generated fragments of nuclei gave rise to a false TUNEL reaction not associated with apoptosis. Mechanical stress from high overpressure shock wave was likely the dominant pathway of tumor damage.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Neoplasias Experimentales/patología , Neoplasias Experimentales/terapia , Animales , Caspasa 3/metabolismo , Terapia por Estimulación Eléctrica/instrumentación , Eosina Amarillenta-(YS) , Diseño de Equipo , Fluorescencia , Hematoxilina , Inmunohistoquímica/métodos , Etiquetado Corte-Fin in Situ , Masculino , Ratas Endogámicas Lew
16.
Biomed Res Int ; 2014: 175398, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25101264

RESUMEN

Narrow band imaging is considered a significant improvement in the possibility of detecting early mucosal lesion of the upper aerodigestive tract. Early detection of mucosal neoplastic lesions is of utmost importance for patients survival. There is evidence that, especially in patients previously treated by means of curative radiotherapy or chemoradiotherapy, the early detection rate of recurrent disease is quite low. The aim of this study was to prove whether the videoendoscopy coupled with NBI might help detect recurrent or secondary tumors of the upper aerodigestive tract. 66 patients previously treated by means of RT or CRT with curative intent were enrolled in the study. All patients underwent transnasal flexible videoendoscopy with NBI mode under local anesthesia. When a suspicious lesion was identified in an ambulatory setting, its nature was proved histologically. Many of these changes were not identifiable by means of conventional white light (WL) endoscopy. The accuracy, sensitivity, specificity, and positive and negative predictive value of the method are very high (88%, 92%, 76%, 96%, and 91%, resp.). Results demonstrate that outpatient transnasal endoscopy with NBI is an excellent method for the follow-up of patients with carcinomas of the larynx and the hypopharynx primarily treated with radiotherapy.


Asunto(s)
Neoplasias Hipofaríngeas/radioterapia , Neoplasias Laríngeas/radioterapia , Imagen de Banda Estrecha/métodos , Recurrencia Local de Neoplasia/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Endoscopía , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Hipofaríngeas/diagnóstico por imagen , Neoplasias Hipofaríngeas/patología , Neoplasias Laríngeas/diagnóstico por imagen , Neoplasias Laríngeas/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/patología , Radiografía
17.
Biomed Res Int ; 2014: 285486, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25025043

RESUMEN

Narrow band imaging (NBI) HDTV (high definition television) magnifying endoscopy is considered to be superior for the accurate display of the microvascular patterns of superficial mucosal lesions. Observation of changes in intraepithelial papillary capillary loops (IPCL) can help distinguish benign from malignant lesions as part of an "optical biopsy." However, IPCL changes in papillomas may be mistaken for spinocellular cancer (SCC). The aim of the study was to determine whether observing microvascular changes alone is sufficient for discriminating between laryngeal SCC and papillomatosis. An additional aim was to identify associated characteristics that could clarify the diagnosis. The study included 109 patients with a suspected laryngeal tumor or papilloma. HDTV NBI magnifying endoscopy was performed during direct laryngoscopy. It was possible to visualize IPCL changes in 82 out of 109 patients (75.2%). In 71 (86.6%) patients, the diagnosis was correctly determined. In 4 (4.9%) cases, the diagnosis of SCC was expressed on the basis of finding pathologic IPCL, but histology did not demonstrate malignancy. To achieve a correct diagnosis using HDTV NBI magnifying endoscopy, it is important not only to observe changes in the shape of IPCL but also to note possible papillary structures with central-axis capillaries typical of papillomatosis.


Asunto(s)
Endoscopía , Neoplasias Laríngeas/diagnóstico , Imagen de Banda Estrecha , Papiloma/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Neoplasias Laríngeas/patología , Masculino , Persona de Mediana Edad , Papiloma/patología
18.
Biomed Res Int ; 2014: 450170, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24800227

RESUMEN

Minimally invasive video-assisted thyroidectomy (MIVAT) and minimally invasive nonendoscopic thyroidectomy (MINET) represent well accepted and reproducible techniques developed with the main goal to improve cosmetic outcome, accelerate healing, and increase patient's comfort following thyroid surgery. Between 2007 and 2011, a prospective nonrandomized study of patients undergoing minimally invasive thyroid surgery was performed to compare advantages and disadvantages of the two different techniques. There were no significant differences in the length of incision to perform surgical procedures. Mean duration of hemithyroidectomy was comparable in both groups, but it was more time consuming to perform total thyroidectomy by MIVAT. There were more patients undergoing MIVAT procedures without active drainage in the postoperative course and we also could see a trend for less pain in the same group. This was paralleled by statistically significant decreased administration of both opiates and nonopiate analgesics. We encountered two cases of recurrent laryngeal nerve palsies in the MIVAT group only. MIVAT and MINET represent safe and feasible alternative to conventional thyroid surgery in selected cases and this prospective study has shown minimal differences between these two techniques.


Asunto(s)
Endoscopía/métodos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Dolor de Cuello/etiología , Nódulo Tiroideo/cirugía , Tiroidectomía/métodos , Grabación en Video/métodos , Parálisis de los Pliegues Vocales/etiología , Adulto , Anciano , Endoscopía/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/efectos adversos , Dolor de Cuello/diagnóstico , Nódulo Tiroideo/complicaciones , Nódulo Tiroideo/patología , Tiroidectomía/efectos adversos , Resultado del Tratamiento , Parálisis de los Pliegues Vocales/diagnóstico
19.
Int J Pediatr Otorhinolaryngol ; 78(7): 990-4, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24794415

RESUMEN

OBJECTIVES: The purpose of this study is to evaluate the characteristics of thyroid gland surgery focusing on malignancies at the pediatric age with the main concern on treatment results and complications in extensive primary treatment. METHODS: The records of all patients 18 years and younger with surgically treated thyroid diseases in the Prague Hospital, Motol, between 1991 and 2006 were retrospectively reviewed. RESULTS: Thyroid surgery was performed on 148 pediatric patients (including 56 carcinomas). The youngest patient involved in the study was seven years old, the oldest patient 18 years old (mean 13.7 years). Most frequent histological cancer type was PTC (42 cases, 75%). Follicular cancer was diagnosed in five cases (8.9%) and medullar cancer in nine cases (16.1%). A prophylactic thyroidectomy was performed in three cases (5.4%) without clinical signs of thyroid tumor with diagnosed RET gene mutation. CONCLUSIONS: We consider total thyroidectomy with subsequent radioiodine ablation and TSH suppression as the basic approach in the treatment protocol of pediatric WDTC. The observed 100% recurrence-free and overall survival together with a low incidence of postoperative complications strongly supports the idea of a total thyroidectomy with selective neck dissection in the treatment of metastases of WDTC and MTC.


Asunto(s)
Carcinoma/cirugía , Neoplasias de la Tiroides/cirugía , Tiroidectomía/estadística & datos numéricos , Adolescente , Carcinoma/genética , Carcinoma/mortalidad , Carcinoma/patología , Niño , Femenino , Humanos , Hipocalcemia/epidemiología , Radioisótopos de Yodo/uso terapéutico , Neoplasias Pulmonares/secundario , Metástasis Linfática , Masculino , Mutación , Disección del Cuello , Complicaciones Posoperatorias/epidemiología , Proteínas Proto-Oncogénicas c-ret/genética , Radioterapia Adyuvante , Estudios Retrospectivos , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/mortalidad , Neoplasias de la Tiroides/patología
20.
Biomed Res Int ; 2014: 516231, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24729975

RESUMEN

Nowadays endoscopic diverticulotomy is the surgical approach of the first choice in treatment of Zenker's diverticulum. We report our experience with this procedure and try to sum up recent recommendations for management of surgery and postoperative care. Data of 34 patients with Zenker's diverticulum, treated by endoscopic carbon dioxide laser diverticulotomy at the Department of Otorhinolaryngology and Head and Neck Surgery, 1st Faculty of Medicine, Charles University, University Hospital Motol, Prague, Czech Republic, were prospectively stored and followed in relatively short period from May 2009 to December 2013. The average length of diverticulum was 32 mm. The average duration of surgery was 32 min. The patients were fed via feeding tube for 6.1 days and antibiotics were administered for 7 days. Mean hospitalization time was 7.4 days. We observed one transient recurrent laryngeal nerve paralysis and no other serious complications. Recurrence rate was 3%. We recommend complete transection of the diverticular septum in one procedure, systemic antibiotic treatment and exclusion of transoral intake for minimally 5 days, and contrast oesophagogram before resumption of oral intake to exclude fistula. Open diverticulectomy should be reserved for cases with inadequate endoscopic exposure and for revision surgery for multiple recurrences from endoscopic diverticulotomies.


Asunto(s)
Esofagoscopía/métodos , Terapia por Láser/métodos , Divertículo de Zenker/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Factores de Tiempo , Divertículo de Zenker/patología
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