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1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 5979-5982, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892480

RESUMO

Current clinical decision-making is based on rapid and subjective functional tests such as 10 m walking. Moreover, greater accuracy can be achieved at the expense of rapidity and costs. In biomechanical laboratories, advanced technologies and musculoskeletal modeling can quantitatively describe the biomechanical reasons underlying gait disorders. Our work aims to blend clinical rapidity and biomechanical accuracy through multi-channel (MC) electromyography (EMG) clustering and real-time neuro-musculoskeletal (NMS) modeling techniques integrated into a sensorized wearable garment that is quick to set up. Here we present a unique pipeline that goes from MC EMG signals to ankle torque estimation following two steps: (1) non-negative matrix factorization (NNMF)-based EMG clustering for the extraction of muscle-specific activations and (2) subject-specific EMG-driven NMS modeling. The results show the potential of NNMF as an electrode clustering tool, as well as the ability to predict joint torque during movements that were not used for the EMG clustering.


Assuntos
Modelos Biológicos , Músculo Esquelético , Tomada de Decisão Clínica , Eletromiografia , Marcha
2.
Data Brief ; 39: 107488, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34729386

RESUMO

Sentinel-2 MSI is one of the core missions of the Copernicus Earth Observation programme of the European Union. This mission shows great potential to map the regional high-resolution spatio-temporal dynamics of land use and land cover. In tropical regions, despite the high revisiting time of 5 days including both Sentinel-2A and 2B satellites, the frequent presence of clouds, cloud-shadows, haze and other atmospheric contaminants are precluding the visibility of the Earth surface up to several months. In this paper we present four annual pan-tropical cloud-free composites computed and exported from Google Earth Engine (GEE) by making use of available Sentinel-2 L1C collection for the period spanning from 2015 to 2020. We furthermore propose empirical approaches to reduce the BRDF effect over tropical forest areas by showing pros and cons of image-based versus swath-based methodologies. Additionally, we provide a dedicated web-platform offering a fast and intuitive way to browse and explore the proposed annual composites as well as layers of potential annual changes as a ready-to-use means to visually identify and verify degradation and deforestation activities as well as other land cover changes.

3.
Sci Adv ; 7(10)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33674308

RESUMO

Accurate characterization of tropical moist forest changes is needed to support conservation policies and to quantify their contribution to global carbon fluxes more effectively. We document, at pantropical scale, the extent and changes (degradation, deforestation, and recovery) of these forests over the past three decades. We estimate that 17% of tropical moist forests have disappeared since 1990 with a remaining area of 1071 million hectares in 2019, from which 10% are degraded. Our study underlines the importance of the degradation process in these ecosystems, in particular, as a precursor of deforestation, and in the recent increase in tropical moist forest disturbances (natural and anthropogenic degradation or deforestation). Without a reduction of the present disturbance rates, undisturbed forests will disappear entirely in large tropical humid regions by 2050. Our study suggests that reinforcing actions are needed to prevent the initial degradation that leads to forest clearance in 45% of the cases.

4.
Data Brief ; 31: 105737, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32490091

RESUMO

Large-scale land cover classification from satellite imagery is still a challenge due to the big volume of data to be processed, to persistent cloud-cover in cloud-prone areas as well as seasonal artefacts that affect spatial homogeneity. Sentinel-2 times series from Copernicus Earth Observation program offer a great potential for fine scale land cover mapping thanks to high spatial and temporal resolutions, with a decametric resolution and five-day repeat time. However, the selection of best available scenes, their download together with the requirements in terms of storage and computing resources pose restrictions for large-scale land cover mapping. The dataset presented in this paper corresponds to global cloud-free pixel based composite created from the Sentinel-2 data archive (Level L1C) available in Google Earth Engine for the period January 2017- December 2018. The methodology used for generating the image composite is described and the metadata associated with the 10 m resolution dataset is presented. The data with a total volume of 15 TB is stored on the Big Data platform of the Joint Research Centre. It can be downloaded per UTM grid zone, loaded into GIS clients and displayed easily thanks to pre-computed overviews.

5.
J Cardiovasc Surg (Torino) ; 54(6): 737-54, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24126511

RESUMO

Diabetic foot pathology represent the more disabling complication of diabetes. More the 1 million of diabetes patients undergo a lower limb amputation per year; 85% of these amputation are preceded by un ulcer that can be avoided by a prevention program. Critical limb ischemia (CLI), the only independent cause of major amputation in diabetic population, can be correctly treated when an early diagnosis is made. Both endoluminal and surgical revascularization procedures can be applied in diabetes with high rate of success when performed by skilled operator. Infection of diabetic foot, in particular in patients suffering from peripheral artery disease (PVD), may rapidly evolves in severe local or systemic infection putting the patient at high risk of major amputation or death. Together with an early diagnosis of infection and ischemia it is mandatory to apply a correct medical and surgical treatment protocol with the aim to control infection and to improve blood perfusion to the foot. In case of infection surgical procedure should be applied first while revascularization procedure will follow soonest. Antibiotic therapy should be chosen considering different local biological pattern and different type of infection. Reconstructive surgery, the last step in treatment of any diabetic foot lesion, must obtain a functional residual foot or a stump that will allow the patient to go back walking soonest with residual good walking capacity.


Assuntos
Pé Diabético/cirurgia , Isquemia/cirurgia , Perna (Membro)/irrigação sanguínea , Procedimentos Cirúrgicos Vasculares/métodos , Humanos , Resultado do Tratamento
8.
J Am Chem Soc ; 131(16): 5809-15, 2009 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-19334787

RESUMO

Applying density functional theory (DFT) calculations to the rational design of catalysts for complex reaction networks has been an ongoing challenge, primarily because of the high computational cost of these calculations. Certain correlations can be used to reduce the number and complexity of DFT calculations necessary to describe trends in activity and selectivity across metal and alloy surfaces, thus extending the reach of DFT to more complex systems. In this work, the well-known family of Brønsted-Evans-Polanyi (BEP) correlations, connecting minima with maxima in the potential energy surface of elementary steps, in tandem with a scaling relation, connecting binding energies of complex adsorbates with those of simpler ones (e.g., C, O), is used to develop a potential-energy surface for ethanol decomposition on 10 transition metal surfaces. Using a simple kinetic model, the selectivity and activity on a subset of these surfaces are calculated. Experiments on supported catalysts verify that this simple model is reasonably accurate in describing reactivity trends across metals, suggesting that the combination of BEP and scaling relations may substantially reduce the cost of DFT calculations required for identifying reactivity descriptors of more complex reactions.

9.
Arch Oral Biol ; 53(10): 985-90, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18539261

RESUMO

OBJECTIVE: Yoghurt consumption leads to a selective decrease in the oral level of mutans streptococci. It is not clear whether this decrease is due to the bactericidal activity of yoghurt or other mechanisms. The present study investigated the differences in susceptibility to yoghurt between several strains of viridans streptococci. DESIGN: The sources of variation were minimised, at the expense of the external validity of the study, using culture collection strains. Each strain was tested separately on five occasions in planktonic form and logarithmic growth phase. Two strains of each of the following Streptococcus species were tested: mutans, sobrinus, gordonii, oralis, parasanguinis and sanguinis. One millilitre [10(8) colony-forming units (cfu)] of each strain was incubated (37 degrees C, 60min) with 9mL of fat-free plain yoghurt containing Streptococcus thermophilus and Lactobacillus bulgaricus (10(8) and 10(7)cfu/g, respectively) in gently vortexed tubes. Survival rates were calculated every 15min by dividing the number of viable cells, obtained using conventional laboratory procedures, by the baseline number. RESULTS: Survival rates were 8% (S. mutans 6519T), 12% (S. mutans 31738), 35% (S. oralis 25671) and >50% (all other species tested) after 15min, and 0.01% (S. mutans) and >10% (all other species tested) after 30min. Overall, S. parasanguinis and S. sobrinus were the most resistant species. When heat-treated yoghurt (<10cfu/g bacteria and inactivated bacteriocins) was used, this antibacterial activity was not found. CONCLUSION: In vitro, yoghurt with live bacteria showed selective anti-mutans activity, suggesting that the overall decrease in mutans streptococci in vivo could be due to a bactericidal effect on S. mutans but not on S. sobrinus.


Assuntos
Antibiose , Estreptococos Viridans/crescimento & desenvolvimento , Iogurte/microbiologia , Contagem de Colônia Microbiana , Humanos , Técnicas In Vitro , Testes de Sensibilidade Microbiana , Streptococcus mutans/crescimento & desenvolvimento , Estreptococos Viridans/classificação
10.
Ann Ig ; 15(5): 477-85, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-14969300

RESUMO

The aim of this study has been to investigate the differences in the health-related behaviour by means of a questionnaire in a sample of elderly (>54 years, 1st generation) and younger adults (<54 years, 2nd generation, all of them sons/daughters of HCV positive subjects), given the high difference in HCV positive prevalence among the two groups (19.4% vs. 2.1%). Most (53.4% vs. 0.0%) of the 1st generation subjects used glass syringes while all the 2nd generation subjects used disposable syringes. Among the elderly, the frequency of hospitalisation (70% vs. 50%), transfusions (11.8% vs. 2.9%) and dental therapy by false dentists (52% vs. 0%) were higher. These results show that the use of non recyclable syringes is the main responsible for the drastic reduction of HCV circulation in the present community, and the consequent decrease in the risk for infection in younger subjects. Moreover, dental therapy was not related to an increased risk for infection, providing that the treatment has been made by a "true" dentist. Finally, the intrafamiliar transmission was not supported by the present data.


Assuntos
Comportamentos Relacionados com a Saúde , Hepatite C/epidemiologia , Adulto , Fatores Etários , Idoso , Assistência Odontológica , Feminino , Humanos , Itália/epidemiologia , Masculino , Prevalência , Fatores de Risco , Seringas
11.
J Musculoskelet Neuronal Interact ; 2(4): 309-20, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15758422

RESUMO

The expansion potential and plasticity of stem cells, adult or embryonic, offer great promise for their use in medical therapies. Recent provocative data suggest that the differentiation potential of adult stem cells may extend to lineages beyond those usually associated with the germ layer of origin. In this review, we describe recent developments related to adult stem cell research and in particular, in the arena of mesenchymal stem cell (MSC) research. Research demonstrates that transduced MSCs injected into skeletal muscle can persist and express secreted gene products. The ability of the MSC to differentiate into cardiomyocytes has been reported and their ability to engraft and modify the pathology in infarcted animal models is of great interest. Research using MSCs in tendon repair provides information on the effects of physical forces on phenotype and gene expression. In turn, MSCs produce changes in their matrix environment in response to those biomechanical forces. Recent data support the potential of MSCs to repair tendon, ligament, meniscus and other connective tissues. Therapeutic applications of adult stem cells are approaching clinical use in several fields, furthering the possibility to regenerate damaged and diseased tissue.

13.
Science ; 284(5411): 143-7, 1999 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-10102814

RESUMO

Human mesenchymal stem cells are thought to be multipotent cells, which are present in adult marrow, that can replicate as undifferentiated cells and that have the potential to differentiate to lineages of mesenchymal tissues, including bone, cartilage, fat, tendon, muscle, and marrow stroma. Cells that have the characteristics of human mesenchymal stem cells were isolated from marrow aspirates of volunteer donors. These cells displayed a stable phenotype and remained as a monolayer in vitro. These adult stem cells could be induced to differentiate exclusively into the adipocytic, chondrocytic, or osteocytic lineages. Individual stem cells were identified that, when expanded to colonies, retained their multilineage potential.


Assuntos
Adipócitos/citologia , Linhagem da Célula , Condrócitos/citologia , Mesoderma/citologia , Osteócitos/citologia , Células-Tronco/citologia , Adulto , Apoptose , Células da Medula Óssea/citologia , Diferenciação Celular , Divisão Celular , Separação Celular , Células Cultivadas , Fibroblastos/citologia , Citometria de Fluxo , Humanos , Pessoa de Meia-Idade , Fenótipo
14.
Eur J Epidemiol ; 13(6): 659-64, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9324212

RESUMO

The effect of milk on dental caries was studied on a sample of 6-to-11-year-old Italian schoolchildren. The daily amount of milk consumed and the frequency of consumption of sucrose-containing foods were obtained by a 24-hour dietary diary. In the subsequent oral examination, the level of visible plaque and the number of decayed, extracted and filled teeth (both primary and permanent) of the children were recorded. 439 children (217 boys) who did not use fluoride prophylaxis and with poor oral hygiene were selected from among 890 children. They were divided into three groups according to the frequency of sucrose consumption. The data were statistically analysed using multiple logistic regression. The children consumed a daily average of 209 +/- 133 ml of milk and there were no differences among the three groups in this respect. As expected, the dental health of the children with low sucrose frequency was significantly better than that of the children with high sucrose frequency. The regression on the whole sample showed a weak, significant, negative association between milk consumption and caries (p < 0.05). In the group of high sucrose-consuming children a negative, highly significant association was found (p < 0.001), while in the two groups of low and moderate sucrose-consuming children no association was found. These data suggest that, in the present sample of children who did not use fluoride and with poor oral hygiene, milk has a caries preventive effect only on those subjects with a high daily sucrose-consuming frequency.


Assuntos
Cárie Dentária/epidemiologia , Sacarose Alimentar/efeitos adversos , Leite , Análise de Variância , Animais , Distribuição de Qui-Quadrado , Criança , Cárie Dentária/etiologia , Cárie Dentária/prevenção & controle , Feminino , Humanos , Itália/epidemiologia , Modelos Logísticos , Masculino , Saúde Bucal , Prevalência
16.
New Microbiol ; 20(1): 55-62, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9037669

RESUMO

The present study evaluated microbiological and clinical changes occurring during the first six months of orthodontic therapy with fixed and removable appliances and the consequent risk for gingivitis and periodontal disease. This study was justified by the disagreement among different authors: only some of them reported gingivitis development and changes in dental plaque composition during orthodontic therapy with fixed appliances, others did not. Thirty, 7-to-15-year-old children, fifteen with fixed and fifteen with removable appliances, previously motivated to oral hygiene, completed the study. They were clinically examined by a dentist at baseline and at the end of the study. Three supra and subgingival microflora samples were collected from the first molars, when the appliances were inserted (T0), 6-8 weeks later (T1) and 6-7 months later (T2). Microflora was examined using dark-field and light microscopes and cultural methods. An indicator of healthy status (percentage of Gram positive cocci in total bacterial count) and some risk indicators for gingivitis (bacterial count evaluated with light microscope, percentage of Gram negative rods) and for periodontitis (motile rod and spirochete percentages, presumptive Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis prevalence) were investigated. Patients with fixed appliances were clinically healthy at T2; yet they showed significantly increased counts, motile rods, subgingival spirochetes and a decrease of Gram positive cocci. At T2, patients with removable appliances were clinically healthy and the only significant microbiological changes were supragingival motile rods and subgingival spirochetes. These data suggest that in the oral hygiene motivated patients of the present study, gingivitis and periodontitis do not occur, during the first six months of treatment: the significant modification of oral microbiota, shown by subjects with fixed appliances, however, suggests that the risk for gingivitis in the following months of therapy is still high and the risk for periodontitis cannot be excluded.


Assuntos
Placa Dentária/diagnóstico , Placa Dentária/microbiologia , Gengivite/microbiologia , Ortodontia Corretiva/métodos , Doenças Periodontais/microbiologia , Adolescente , Aggregatibacter actinomycetemcomitans/isolamento & purificação , Técnicas Bacteriológicas , Criança , Contagem de Colônia Microbiana , Gengivite/epidemiologia , Bactérias Gram-Negativas/isolamento & purificação , Cocos Gram-Positivos/isolamento & purificação , Humanos , Estudos Longitudinais , Aparelhos Ortodônticos/efeitos adversos , Ortodontia Corretiva/efeitos adversos , Doenças Periodontais/epidemiologia , Porphyromonas gingivalis/isolamento & purificação , Prevalência , Fatores de Risco
17.
Minerva Stomatol ; 46(10): 561-6, 1997 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-9432563

RESUMO

BACKGROUND: The aim of the present study was the evaluation of the effectiveness as sterilizer of a modified version of a microwave device, which was previously tested by the same authors and found unsatisfactory. MATERIALS AND METHODS: Dental mirrors were contaminated by 10(4)-10(9) microorganisms of Stapbylococcus aureus and spores of Bacillus subtilis and Bacillus stearothermophilus. The inocula used were both wet and dry. The duration of the treatment was 4 minutes. Three series of tests were made: 1) microwaves and "adjuvant" solution (as suggested by the producer of the device); 2) microwaves only (in place of the "adjuvant" solution, a Na Cl 0.9% was used); 3) "adjuvant" solution only (into an oven at 25 degrees C). RESULTS: In the 1st and 3rd series of tests all the microorganisms and the spores were killed. In the 2nd series of tests a bactericidal effect against some, not all, microorganisms of the S. aureus species and against spores of B. subtilis and B. stearothermophilus was found. CONCLUSIONS: The results of this study suggest that the device tested has a sterilizing activity, which, however, is not due to the activity of microwaves only; but to the combined activity of microwaves, "adjuvant" solution and temperature (since inside the device, at the end of the treatment the temperature on the mirrors was 94 degrees C).


Assuntos
Instrumentos Odontológicos , Desinfecção/instrumentação , Micro-Ondas
18.
Electromyogr Clin Neurophysiol ; 36(6): 357-60, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8891475

RESUMO

The aim of the present study was to assess the habituation of the blink responses evoked by repetitive auditory stimuli in patients with Parkinson's disease in different clinical states. We studied 28 parkinsonian patients. Eighteen patients without motor fluctuations were studied off and on levodopa, on two different sessions, one week apart. The remaining 10 parkinsonians had the wearing off phenomenon and were studied while being off their medication and while ON and OFF, as determined clinically, after a single dose of levodopa. Twelve age-matched controls were also studied in a single session. Unilateral auditory 1 kHz, 105 dB stimuli were delivered at a frequency of 0.2 Hz. The number of responses (R) from the orbicularis oculi was registered. R values were significantly smaller in controls and in treated parkinsonians than in untreated patients. R was also significantly smaller when ON than at baseline and when OFF in parkinsonians with the wearing off phenomenon. These results suggest a failure of the inhibition of the acoustic-palpebral reflex in Parkinson's disease. The improvement with levodopa and the similarities between the clinical and the electrophysiological changes suggest a dopaminergic role in the inhibition of this brainstem reflex.


Assuntos
Antiparkinsonianos/uso terapêutico , Piscadela/efeitos dos fármacos , Dopaminérgicos/uso terapêutico , Habituação Psicofisiológica/efeitos dos fármacos , Levodopa/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Reflexo Acústico/efeitos dos fármacos , Estimulação Acústica , Antiparkinsonianos/administração & dosagem , Tronco Encefálico/efeitos dos fármacos , Tronco Encefálico/fisiologia , Estudos de Casos e Controles , Dopaminérgicos/administração & dosagem , Eletromiografia , Feminino , Humanos , Levodopa/administração & dosagem , Masculino , Pessoa de Meia-Idade , Músculos Oculomotores/efeitos dos fármacos , Músculos Oculomotores/fisiologia , Doença de Parkinson/fisiopatologia , Reflexo Anormal/efeitos dos fármacos
19.
Blood ; 87(10): 4348-57, 1996 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-8639795

RESUMO

We attempted to determine the frequency of normal hematopoietic stem cells (HSC) and contaminating leukemic cells in mobilized peripheral blood (MPB) collected from chronic myeloid leukemia (CML) patients, intolerant of alpha-interferon or with interferon-resistant disease. A total of 14 MPB samples, six from patients in chronic phase (CP) and eight from patients in accelerated phase or blast crisis (AP/BC) were studied. Cytogenetic analysis of MPB collected from AP/BC patients showed that 100% of the cells were Ph+, whereas cells from four of five CP MPB were Ph-. By contrast, fluorescence in situ hybridization (FISH) analysis of CP MPB showed a mean frequency of 14.7% Ph+ cells, while AP/BC MPB contained 39.2% Ph+ cells. In an attempt to purify normal HSC, subpopulations of the MPB CD34+ cells were isolated based on expression of the Thy-1 antigen (CDw90). The mean Ph+ cell frequency as determined by FISH within the CD34+Thy-1+Lin- and CD34+Thy-1-Lin- populations from CP patients was 19.2% and 33.9%, respectively. In the AP/BC patients, levels of residual leukemic cells were significantly greater with mean Ph+ cell frequencies of 59.2% and 72.7% for the CD34+Thy-1+Lin- and CD34+Thy-1-Lin- fractions, respectively. The frequency of cobblestone area forming cells (CAFC) was used as a means of quantitating the numbers of functional HSC within these cell subpopulations. The mean CAFC frequency was 1 of 19 for the CD34+Thy-1+Lin- cells as compared with 1 of 133 for the Thy-1-fraction indicating a higher frequency of primitive progenitor cells in the Thy-1+ subpopulation. CD34+ cell subsets from two patients were also injected into SCID-hu bone assays to determine the in vivo behavior of these cell populations. After 8 weeks, multilineage donor engraftment was observed in these grafts. FISH analysis of the donor cells within the grafts showed that 55.3% and 60.0% of the cells were Ph+. We conclude that unfractionated MPB from this patient population is not leukemia-free and that the CD34+Thy-1+Lin- cell subpopulation, although predominantly enriched for normal HSC, still contains substantial numbers of residual leukemic cells.


Assuntos
Antígenos CD34/análise , Contagem de Células Sanguíneas , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas , Fatores Imunológicos/uso terapêutico , Separação Imunomagnética , Interferon-alfa/uso terapêutico , Leucaférese , Leucemia Mielogênica Crônica BCR-ABL Positiva/sangue , Células Neoplásicas Circulantes , Adolescente , Adulto , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Crise Blástica/sangue , Crise Blástica/terapia , Transplante Ósseo , Cisplatino/administração & dosagem , Cisplatino/farmacologia , Terapia Combinada , Resistência a Medicamentos , Etoposídeo/administração & dosagem , Etoposídeo/farmacologia , Transplante de Tecido Fetal , Citometria de Fluxo , Sobrevivência de Enxerto , Fator Estimulador de Colônias de Granulócitos/farmacologia , Células-Tronco Hematopoéticas/química , Humanos , Ifosfamida/administração & dosagem , Ifosfamida/farmacologia , Hibridização in Situ Fluorescente , Leucaférese/métodos , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Leucemia Mieloide de Fase Acelerada/sangue , Leucemia Mieloide de Fase Acelerada/terapia , Leucemia Mieloide de Fase Crônica/sangue , Leucemia Mieloide de Fase Crônica/terapia , Camundongos , Camundongos SCID , Pessoa de Meia-Idade , Transplante de Neoplasias , Células Neoplásicas Circulantes/química , Cromossomo Filadélfia , Quimera por Radiação , Organismos Livres de Patógenos Específicos , Transplante Heterólogo
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