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1.
Environ Res ; 262(Pt 1): 119802, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39147188

RESUMO

Forest disturbance regimes across biomes are being altered by interactive effects of global change. Establishing baselines for assessing change requires detailed quantitative data on past disturbance events, but such data are scarce and difficult to obtain over large spatial and temporal scales. The integration of remote sensing with dense time series analysis and cloud computing platforms is enhancing the ability to monitor historical disturbances, and especially non-stand replacing events along climatic gradients. Since the integration of such tools is still scarce in Mediterranean regions, here, we combine dense Landsat time series and the Continuous Change Detection and Classification - Spectral Mixture Analysis (CCDC-SMA) method to monitor forest disturbance in continental Spain from 1985 to 2023. We adapted the CCDC-SMA method for improved disturbance detection creating new spectral libraries representative of the study region, and quantified the year, month, severity, return interval, and type of disturbance (stand replacing, non-stand replacing) at a 30 m resolution. In addition, we characterised forest disturbance regimes and trends (patch size and severity, and frequency of events) of events larger than 0.5 ha at the national scale by biome (Mediterranean and temperate) and forest type (broadleaf, needleleaf and mixed). We quantified more than 2.9 million patches of disturbed forest, covering 4.6 Mha over the region and period studied. Forest disturbances were on average larger but less severe in the Mediterranean than in the temperate biome, and significantly larger and more severe in needleleaf than in mixed and broadleaf forests. Since the late 1980s, forest disturbances have decreased in size and severity while increasing in frequency across all biomes and forest types. These results have important implications as they confirm that disturbance regimes in continental Spain are changing and should therefore be considered in forest strategic planning for policy development and implementation.

2.
Environ Res ; 259: 119432, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38944104

RESUMO

The Mediterranean Basin has experienced substantial land use changes as traditional agriculture decreased and population migrated from rural to urban areas, which have resulted in a large forest cover increase. The combination of Landsat time series, providing spectral information, with lidar, offering three-dimensional insights, has emerged as a viable option for the large-scale cartography of forest structural attributes across large time spans. Here we develop and test a comprehensive framework to map forest above ground biomass, canopy cover and forest height in two regions spanning the most representative biomes in the peninsular Spain, Mediterranean (Madrid region) and temperate (Basque Country). As reference, we used lidar-based direct estimates of stand height and forest canopy cover. The reference biomass and volume were predicted from lidar metrics. Landsat time series predictors included annual temporal profiles of band reflectance and vegetation indices for the 1985-2023 period. Additional predictor variables including synthetic aperture radar, disturbance history, topography and forest type were also evaluated to optimize forest structural attributes retrieval. The estimates were independently validated at two temporal scales, i) the year of model calibration and ii) the year of the second lidar survey. The final models used as predictor variables only Landsat based metrics and topographic information, as the available SAR time-series were relatively short (1991-2011) and disturbance information did not decrease the estimation error. Model accuracies were higher in the Mediterranean forests when compared to the temperate forests (R2 = 0.6-0.8 vs. 0.4-0.5). Between the first (1985-1989) and the last (2020-2023) decades of the monitoring period the average forest cover increased from 21 ± 2% to 32 ± 1%, mean height increased from 6.6 ± 0.43 m to 7.9 ± 0.18 m and the mean biomass from 31.9 ± 3.6 t ha-1 to 50.4 ± 1 t ha-1 for the Mediterranean forests. In temperate forests, the average canopy cover increased from 55 ± 4% to 59 ± 3%, mean height increased from 15.8 ± 0.77 m to 17.3 ± 0.21m, while the growing stock volume increased from 137.8 ± 8.2 to 151.5 ± 3.8 m3 ha-1. Our results suggest that multispectral data can be successfully linked with lidar to provide continuous information on forest height, cover, and biomass trends.


Assuntos
Biomassa , Monitoramento Ambiental , Florestas , Espanha , Monitoramento Ambiental/métodos , Tecnologia de Sensoriamento Remoto , Árvores/crescimento & desenvolvimento
4.
Anal Bioanal Chem ; 406(6): 1619-27, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24337135

RESUMO

The rapid development of protein-based pharmaceuticals highlights the need for robust analytical methods to ensure their quality and stability. Among proteins used in pharmaceutical applications, an important and ever increasing role is represented by monoclonal antibodies and large proteins, which are often modified to enhance their activity or stability when used as drugs. The bioactivity and the stability of those proteins are closely related to the maintenance of their complex structure, which however are influenced by many external factors that can cause degradation and/or aggregation. The presence of aggregates in these drugs could reduce their bioactivity and bioavailability, and induce immunogenicity. The choice of the proper analytical method for the analysis of aggregates is fundamental to understand their (size) dimensional range, their amount, and if they are present in the sample as generated by an aggregation or as an artifact due to the method itself. Size exclusion chromatography is one of the most important techniques for the quality control of pharmaceutical proteins; however, its application is limited to relatively low molar mass aggregates. Among the techniques for the size characterization of proteins, field-flow fractionation (FFF) represents a competitive choice because of its soft mechanism due to the absence of a stationary phase and application in a broader size range, from nanometer- to micrometer-sized analytes. In this paper, the microcolumn variant of FFF, the hollow-fiber flow FFF, was online coupled with multi-angle light scattering, and a method for the characterization of aggregates with high reproducibility and low limit of detection was demonstrated employing an avidin derivate as sample model.


Assuntos
Fracionamento por Campo e Fluxo/métodos , Proteínas/química , Animais , Avidina/química , Avidina/isolamento & purificação , Bovinos , Lasers , Luz , Limite de Detecção , Tamanho da Partícula , Desnaturação Proteica , Proteínas/isolamento & purificação , Reprodutibilidade dos Testes , Espalhamento de Radiação , Soroalbumina Bovina/química , Soroalbumina Bovina/isolamento & purificação
5.
Phys Rev Lett ; 110(18): 180601, 2013 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-23683183

RESUMO

We report an experimental and theoretical analysis of the energy exchanged between two conductors kept at different temperature and coupled by the electric thermal noise. Experimentally we determine, as functions of the temperature difference, the heat flux, the out-of-equilibrium variance, and a conservation law for the fluctuating entropy, which we justify theoretically. The system is ruled by the same equations as two Brownian particles kept at different temperatures and coupled by an elastic force. Our results set strong constraints on the energy exchanged between coupled nanosystems held at different temperatures.

7.
Chirurgia (Bucur) ; 107(2): 195-8, 2012.
Artigo em Ro | MEDLINE | ID: mdl-22712348

RESUMO

The use of allografts in the surgical treatment of enenlarged hiatal hernias is a current hot topic of discussion. Using meshes in order to strengthen the hiatus of the esophagus is an efficient procedure which reduces the risk of reoccurences. In order to consolidate the initial surgical treatment of the enlarged hiatal hernias, polypropylene, polytetrafluoroethylene and biomaterial meshes are mainly used. There are ongoing discussions with regards to the use of meshes, their type and positioning. Although mesh usage is associated with a low recurrence rate, numerous authors have described complications such as: meshes migrating into the esophagus (caused by the alloplastic material used in the hiatoplasty), strictures, dysphagia, ulcers or perforations. From experience, the mesh used in the surgical treatment of hiatal hernia should preferably be non-biological and must be placed circumferentially, while fermly grounded at the pillar of the diaphragm. The correct placing of the mesh lowers the risk of strictures and degradation. Further prospective studies are needed in order to clarify the best method of surgically treating enlarged hiatal hernias.


Assuntos
Hérnia Hiatal/cirurgia , Próteses e Implantes , Animais , Materiais Biocompatíveis , Modelos Animais de Doenças , Feminino , Polipropilenos , Politetrafluoretileno , Coelhos , Telas Cirúrgicas , Transplante Homólogo/métodos , Resultado do Tratamento
8.
Ultramicroscopy ; 109(3): 264-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19110377

RESUMO

Nanoscale confinement of the magnetization in a magnetic element often results in the creation of a vortex structure. The vortex equilibrium state is characterized by the curling of the in-plane magnetization (chirality) and an out-of-plane core magnetization. The polarity of the vortex core can point up or down, independent of the chirality, and, thus, magnetic elements with a vortex core are interesting as four-state logic elements. We present an easy-to-use, quantitative method for the determination of both chirality and polarity from a single Fresnel image. This method offers direct evidence of the three-dimensional structure of a magnetic vortex and has significant advantages over the more complex methods currently in use.

9.
Anticancer Res ; 15(4): 1355-8, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7544565

RESUMO

The effect of a combination of TNP-470 (AGM-1470, an anti-angiogenic agent) and hyperthermia on tumor growth was examined using human esophageal (ESO-2) and gastric (NSC-8) cancers transplantable to nude mice. TNP-470 alone at a dose of 30 mg/kg three times a week for 2 weeks was sufficient to obtain an antitumor effect. A combination of this dose of TNP-470 and 43 degrees C hyperthermia for 30 min inhibited tumor growth markedly in comparison with either treatment alone. It was considered that angiogenesis after hyperthermia was inhibited by TNP-470, and then regrowth of the tumor cells was potently suppressed by reduction of O2 pressure, pH and nutrient supply in the tumor tissue.


Assuntos
Antibióticos Antineoplásicos/uso terapêutico , Neoplasias Esofágicas/terapia , Hipertermia Induzida , Neovascularização Patológica/prevenção & controle , Sesquiterpenos/uso terapêutico , Neoplasias Gástricas/terapia , Animais , Terapia Combinada , Cicloexanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , O-(Cloroacetilcarbamoil)fumagilol , Transplante Heterólogo
10.
Int Dent J ; 47(4): 194-8, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9532459

RESUMO

The purpose of this survey was to assess the oral health situation of an industrial population in Romania. A total of 311 male and female employees (18-62 years-of-age) were clinically examined according to the WHO Basic Methods criteria and responded to an oral health questionnaire on dental knowledge and health care habits. In the younger age groups, the amount of untreated dental caries was high (18-24 years: DT = 5.7, DMFT = 8.9) whereas missing teeth were prominent in older employees (45 years or more: MT = 7.6, DMFT = 11.9). At age 25-44, 72 per cent had gingival bleeding and calculus. Dental knowledge was relatively poor, and 28 per cent of the participants indicated actual need for treatment. Dental visits within the previous 12 months were reported by 24 per cent of the employees, and 39 per cent had had a tooth extracted at their most recent visit. The study emphasises the need for reorientation of oral health care in Romania, and the relevance of industrial dental services for the implementation of oral health promotion and prevention is highlighted.


Assuntos
Cárie Dentária/epidemiologia , Saúde Ocupacional/estatística & dados numéricos , Perda de Dente/epidemiologia , Adolescente , Adulto , Análise de Variância , Distribuição de Qui-Quadrado , Índice CPO , Assistência Odontológica/estatística & dados numéricos , Dentaduras/estatística & dados numéricos , Feminino , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Higiene Bucal/estatística & dados numéricos , Índice Periodontal , Romênia/epidemiologia
11.
Gan To Kagaku Ryoho ; 24(1): 43-7, 1997 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-9020944

RESUMO

Combined chemotherapy of 5-FU and CDDP is useful for advanced or recurrent gastric cancer. To evaluate the efficacy of this chemotherapy, using human gastric carcinoma (NSC-30) maintained in the subcutaneous (sc) space in nude mice, we designed the following four experimental groups: 1) control group, 2) 5-FU group, 3) CDDP group, and 4) combined therapy group of 5-FU and CDDP (FP group). 5-FU (150 mg/kg) was injected into the intraperitoneal space for seven days using AlZet osmotic pumps. CDDP (9 mg/kg) was injected into the intraperitoneal space at one time. The tumor growth of drug administered groups was inhibited compared with the control group, especially in the FP group. Body weight and general condition of nude mice did not differ between groups. We also measured tumor concentrations of 5-FU and thymidylate synthetase (TS) total, free, inhibition rate between 5-FU group and FP group. The tumor 5-FU concentration of FP group was slightly higher than in 5-FU group, but the TS inhibition rate was almost the same. In conclusion, this combined therapy using Alzet osmotic pump is a useful drug sensitivity test as a conventional system.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Animais , Divisão Celular/efeitos dos fármacos , Cisplatino/administração & dosagem , Fluoruracila/administração & dosagem , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Tamanho do Órgão , Neoplasias Gástricas/patologia
12.
Chirurgia (Bucur) ; 95(3): 285-9, 2000.
Artigo em Ro | MEDLINE | ID: mdl-14768335

RESUMO

The authors present a study based on 4 cases of fistulous communication between the terminal digestive tube and the genitourinary tract, which appeared after surgery and radiation therapy for carcinoma of the uterine cervix. The diagnosis criteria (symptoms, clinical and imagistic findings), the objectives of the surgical treatment (external digestive derivation, treatment of the fistula and reconstruction of the digestive tube), the steps of the operation and the early and late postoperative evolution are pointed out. The conclusions are shown at the end.


Assuntos
Lesões por Radiação/complicações , Fístula Retovaginal/etiologia , Fístula Vesicovaginal/etiologia , Adulto , Carcinoma/radioterapia , Feminino , Humanos , Pessoa de Meia-Idade , Lesões por Radiação/cirurgia , Fístula Retovaginal/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias do Colo do Útero/radioterapia , Fístula Vesicovaginal/cirurgia
13.
Chirurgia (Bucur) ; 95(1): 75-8, 2000.
Artigo em Ro | MEDLINE | ID: mdl-14959646

RESUMO

The authors are presenting the case of a 53 year-old patient, suffering from type II diabetes mellitus and ankylosing spondylitis, admitted in our clinic in July 1997 for gastrojejunocolic fistula, 5 years after a transmesocolic gastrojejunostomy for obstructive chronic duodenal ulcer. The severe metabolic disorders and the radiologic aspects which led to the diagnosis, as well as the morphopathologic lesions found and the ways to approach the fistula, the stenotic duodenal ulcer and the reconstruction of the digestive continuity in a single surgical procedure are further discussed. The conclusions are shown at the end.


Assuntos
Úlcera Duodenal/cirurgia , Gastroenterostomia/efeitos adversos , Fístula Intestinal/etiologia , Humanos , Fístula Intestinal/cirurgia , Masculino , Pessoa de Meia-Idade , Reoperação , Resultado do Tratamento
14.
J Chromatogr A ; 1372C: 196-203, 2014 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-25468501

RESUMO

Monoclonal antibodies (mAbs) are promising reagents both for the manufacture of drug substances and for their employment as a drug themselves, but to be approved for utilization, according to FDA recommendations and WHO guidelines, they have to undergo verifications regarding their purity, stability and percentage of aggregates. Moreover, stability tests of lots have to be performed in order to verify molecular size distribution over time and lot-to-lot consistency. Recent works in literature have highlighted the need for suitable, sensitive and reliable complementary analytical techniques for the characterization of mAbs and quantification of aggregates. Size-exclusion chromatography (SEC) is the reference technique in the biopharmaceutical industry for its robustness, high performance and simple use; however it presents some limitations especially toward the separation and detection of aggregates with high molecular weight. On the other hand, flow field-flow fractionation (F4) in its miniaturized version (hollow fiber flow field-flow fractionation, HF5) shows comparable performances with interesting additional advantages: a broad size range, gentle separation mechanism with low dilution factor and higher sensitivity. To propose HF5 as a complementary technique for evaluating aggregates' content in mAbs samples, a comparative study of both SEC and HF5 performances has been made. In this work, SEC and HF5 were coupled with UV and multi-angle light scattering detection and employed first in separating standard samples of proteins mixture used as a sample model. Then, a screening of mobile phases and an evaluation of separation performances was performed on a therapeutic mAbs formulation, demonstrating the complementarities between SEC and HF5 and their possible use as a separative platform approach for the characterization and quality control of protein drugs.

15.
Rev Med Chir Soc Med Nat Iasi ; 116(1): 214-7, 2012.
Artigo em Ro | MEDLINE | ID: mdl-23077898

RESUMO

UNLABELLED: The esophagogastric junction is a controversial anatomical area, due to its sphincteric mechanism which does not show an obvious anatomical basis. The aim of this study is to investigate the anatomical components that endoscopically indicate the mucosal esophagogastric junction in hiatal hernia patients. MATERIAL AND METHODS: The esophagogastric junction was investigated in 27 hiatal hernia patients undergoing surgery. Hiatal hernia is an extension of the stomach situated between the esophagogastric junction and the diaphragmatic indentation. The following types of hiatal hernia were found: sliding hiatal hernia (type I) in 4 patients (14.81%), rolling hiatal hernia (type II) in 2 (7.4%), mixed hiatal hernia (type III) in 12 (44.44%), type IV hiatal hernia in 4 (14.81%) and recurrent hiatal hernia in 5 (18.51%). Of the 27 hiatal hernia patients, 8 (29.6%) were operated using classical procedures: laparotomy--6 (75%) and laparoscopic surgery--2 (25%). RESULTS: The angle of His cannot be used for marking the mucosal esophagogastric junction due to the severe damage of the lower esophageal sphincter in hiatal hernia patients. The squamocolumnar junction is displaced in hiatal hernia patients and was not an option for the study group. The distal end of the esophageal longitudinal palisading vessels needs medication (proton pump inhibitors that reduce the gastric acid production), in order to enhance the visibility of these vessels. The proximal end of gastric longitudinal mucosal folds proved to be the most reliable site to identify endoscopically the mucosal esophagogastric junction. CONCLUSIONS: The anatomical structure of the esophagogastric junction differs in hiatal hernia patients and these peculiarities are very important in surgery.


Assuntos
Esfíncter Esofágico Superior/anatomia & histologia , Junção Esofagogástrica/anatomia & histologia , Hérnia Hiatal/patologia , Hérnia Hiatal/cirurgia , Laparoscopia , Endoscopia Gastrointestinal/métodos , Esfíncter Esofágico Inferior/anatomia & histologia , Hérnia Hiatal/classificação , Humanos , Estômago/anatomia & histologia , Procedimentos Cirúrgicos Operatórios , Resultado do Tratamento
20.
Virologie ; 32(1): 3-7, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7303490

RESUMO

Significant differences concerning the in vitro reaction spectrum were found between two groups of 30 anti-HBe samples, one from apparently healthy HBsAg carriers, the other from HBsAg-positive acute viral hepatitis (AVH) patients : the mean number of positive reactions per anti-HBe sample was of 7.00 +/- 2.25 in the former and of 3.60 +/- 1.42 in the latter group. The broader reaction spectrum of anti-HBe from apparently healthy subjects (overall positivity percentage--54%, as against 26% in AVH patients) suggests some explanations regarding the different evolution modalities of hepatitis B virus infection in terms of the organism's capacity to develop a specific response.


Assuntos
Anticorpos Antivirais/análise , Portador Sadio/imunologia , Anticorpos Anti-Hepatite B/análise , Antígenos da Hepatite B/imunologia , Antígenos E da Hepatite B/imunologia , Hepatite B/imunologia , Afinidade de Anticorpos , Reações Antígeno-Anticorpo , Antígenos de Superfície da Hepatite B/análise , Antígenos de Superfície da Hepatite B/imunologia , Antígenos E da Hepatite B/análise , Humanos
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